The field of thermoelectric research has undergone a renaissance and boom in the fast two decades, largely fueled by the prospect of engineering electronic and phononic properties in nanostructures, among which semiconductor nanowires (NWs) have served both as an important platform to investigate fundamental thermoelectric transport phenomena and as a promising route for high thermoelectric performance for device applications. In this report we theoretical studied the carrier diffusion and phonon-drag contribution to thermoelectric performance of silicon nanowires and compared with the existing experimental data. We observed a good agreement between theoretical data and experimental observations in the overall temperature range from 50 – 350 K. Electron diffusion thermopower is found to be dominant mechanism in the low temperature range and shows linear dependence with temperature.
I show how much GW corrections are important not only for the band structure but also in the calculation of the electron-phonon matrix elements. I present different examples and comparison with the experimental results.
I show how much GW corrections are important not only for the band structure but also in the calculation of the electron-phonon matrix elements. I present different examples and comparison with the experimental results.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
The driving engine for the exponential growth of digital information processing systems is scaling down the transistor dimensions. For decades, this has enhanced the device performance and density. However, the International Technology Roadmap for Semiconductors (ITRS) states the end of Moore’s law in the next decade due to the scaling challenges of silicon-based CMOS electronics, e.g. extremely high power density. The forward-looking solutions are the utilization of emerging materials and devices for integrated circuits, e.g. carbon-based materials. The presentation of my Ph.D. work focuses on graphene, one atomic layer of carbon sheet, experimentally discovered in 2004. Since fabrication technology of emerging materials is still in early stages, transistor modeling has been playing an important role for evaluating futuristic graphene-based devices and circuits. The device has been simulated by solving a quantum transport model based on non-equilibrium Green’s function (NEGF) approach, which fully treats short channel-length electrostatic effects and the quantum tunneling effects, leading to the technology exploration of graphene nanoribbon field effect transistors (GNR FETs) for the future. This research presents a comprehensive study of the width-dependence performance of the GNR FETs and the scaling of its channel length down to 2.5 nanometer, investigating its potential use beyond-CMOS emerging technology.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Fundamentals of modern physics, the de-Broglie hypothesisPraveen Vaidya
The presentation uploaded here educates about the failure of classical physics to explain Blackbody radiation and the success of quantum theory to explain the Blackbody radiation spectrum and other phenomena, the de-Broglie hypothesis and its significance, nature of de-broglie waves and the representation. Numerical problems are given at the end.
The present article gives the fundamental properties magnetism, different materials, properties of different magnetic materials like, dia,para and ferro magnetic materials. The notes also explain how magnetism appear in materials, type of magnets and brief applications of magnetic materials. The materials is best for undergraduate science and engineering students and any other people of interest in magnetism
In this article, we studied the past and existing research in nanowire (NW) especially based on SiGe NWs. The basic Thermoelectric (TE) principles and theories are introduced and the factors that may influence the TE performance of SiGe NWs are discussed. The superiority of the group IV material-based NWs as TE materials are detailed with feasible structures while their fabrication methods and TE measurements are also reviewed. The existing SiGe NW are discussed for their potential applications and the feasible applications are illustrated. Finally, the variation of parameter TE on Temperature and carrier concentration is discussed and compare theoretically with the available experimental data.
Study of Boron Based Superconductivity and Effect of High Temperature Cuprate...IOSR Journals
This paper illustrates the main normal and Boron superconducting state temperature properties of magnesium diboride, a substance known since early 1950's, but lately graded to be superconductive at a remarkably high critical temperature Tc=40K for a binary synthesis. What makes MgB2 so special? Its high Tc, simple crystal construction, large coherence lengths, high serious current densities and fields, lucidity of surface boundaries to current promises that MgB2 will be a good material for both large scale applications and electronic devices. Throughout the last seven month, MgB2 has been fabricated in various shape, bulk, single crystals, thin films, ribbons and wires. The largest critical current densities >10MA/cm2 and critical fields 40T are achieved for thin films. The anisotropy attribution inferred from upper critical field measurements is still to be resolved, a wide range of values being reported, γ = 1.2 ÷ 9. Also there is no consensus about the existence of a single anisotropic or double energy cavity. One central issue is whether or not MgB2 represents a new class of superconductors, being the tip of an iceberg that waits to be discovered. Until now MgB2 holds the record of the highest Tc among simple binary synthesis. However, the discovery of superconductivity in MgB2 revived the interest in non-oxides and initiated a search for superconductivity in related materials, several synthesis being already announced to become superconductive: TaB2, BeB2.75, C-S composites, and the elemental B under pressure.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
The driving engine for the exponential growth of digital information processing systems is scaling down the transistor dimensions. For decades, this has enhanced the device performance and density. However, the International Technology Roadmap for Semiconductors (ITRS) states the end of Moore’s law in the next decade due to the scaling challenges of silicon-based CMOS electronics, e.g. extremely high power density. The forward-looking solutions are the utilization of emerging materials and devices for integrated circuits, e.g. carbon-based materials. The presentation of my Ph.D. work focuses on graphene, one atomic layer of carbon sheet, experimentally discovered in 2004. Since fabrication technology of emerging materials is still in early stages, transistor modeling has been playing an important role for evaluating futuristic graphene-based devices and circuits. The device has been simulated by solving a quantum transport model based on non-equilibrium Green’s function (NEGF) approach, which fully treats short channel-length electrostatic effects and the quantum tunneling effects, leading to the technology exploration of graphene nanoribbon field effect transistors (GNR FETs) for the future. This research presents a comprehensive study of the width-dependence performance of the GNR FETs and the scaling of its channel length down to 2.5 nanometer, investigating its potential use beyond-CMOS emerging technology.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Fundamentals of modern physics, the de-Broglie hypothesisPraveen Vaidya
The presentation uploaded here educates about the failure of classical physics to explain Blackbody radiation and the success of quantum theory to explain the Blackbody radiation spectrum and other phenomena, the de-Broglie hypothesis and its significance, nature of de-broglie waves and the representation. Numerical problems are given at the end.
The present article gives the fundamental properties magnetism, different materials, properties of different magnetic materials like, dia,para and ferro magnetic materials. The notes also explain how magnetism appear in materials, type of magnets and brief applications of magnetic materials. The materials is best for undergraduate science and engineering students and any other people of interest in magnetism
In this article, we studied the past and existing research in nanowire (NW) especially based on SiGe NWs. The basic Thermoelectric (TE) principles and theories are introduced and the factors that may influence the TE performance of SiGe NWs are discussed. The superiority of the group IV material-based NWs as TE materials are detailed with feasible structures while their fabrication methods and TE measurements are also reviewed. The existing SiGe NW are discussed for their potential applications and the feasible applications are illustrated. Finally, the variation of parameter TE on Temperature and carrier concentration is discussed and compare theoretically with the available experimental data.
Study of Boron Based Superconductivity and Effect of High Temperature Cuprate...IOSR Journals
This paper illustrates the main normal and Boron superconducting state temperature properties of magnesium diboride, a substance known since early 1950's, but lately graded to be superconductive at a remarkably high critical temperature Tc=40K for a binary synthesis. What makes MgB2 so special? Its high Tc, simple crystal construction, large coherence lengths, high serious current densities and fields, lucidity of surface boundaries to current promises that MgB2 will be a good material for both large scale applications and electronic devices. Throughout the last seven month, MgB2 has been fabricated in various shape, bulk, single crystals, thin films, ribbons and wires. The largest critical current densities >10MA/cm2 and critical fields 40T are achieved for thin films. The anisotropy attribution inferred from upper critical field measurements is still to be resolved, a wide range of values being reported, γ = 1.2 ÷ 9. Also there is no consensus about the existence of a single anisotropic or double energy cavity. One central issue is whether or not MgB2 represents a new class of superconductors, being the tip of an iceberg that waits to be discovered. Until now MgB2 holds the record of the highest Tc among simple binary synthesis. However, the discovery of superconductivity in MgB2 revived the interest in non-oxides and initiated a search for superconductivity in related materials, several synthesis being already announced to become superconductive: TaB2, BeB2.75, C-S composites, and the elemental B under pressure.
Study the effect of Mn2+ ions on the ac electrical properties of some iron do...IJRES Journal
Oxide glasses doped with transition metal ions are of high interest because of their variant applications in both science and technology fields. However, the normal melt quench method have used to prepared some iron doped phosphate glasses according the following molecular formula: (65-x) mol% P2O5 - 20 mol% Na2O - 15 mol% Fe2O3 - x mol% MnO, Where x= 0, 5,10, 20, 25. The room temperature Mössbauer Effect ME Spectra used to characterized the glassy state homogeneity of these glasses. ME spectra show, for all glasses, no magnetic field participate which mean good glassy state formation. The ac electrical transport properties were also measured, as function of temperature up to 500k. It was found that the ac conductivity increased with the gradual increase of Mn2+ cations, while the electrical activation energy decreased.
Electrical transport properties of nanocrystalline and bulk nickel.pdfProximaCentauri15
In this work, the comparative study on the electrical transport properties of nanocrystalline nickel
ferrite (NiFe2O4) and its bulk counterpart has been carried out in detail by using complex impedance
spectroscopy in a wide range of frequencies (100 Hz–1 MHz) and temperatures (40 °C–320 °C). The
dispersive nature of the dielectric constant and loss factor is explained by the Maxwell-Wagner model
and Koop’s phenomenological theory. The value of the dielectric constant for nanocrystalline nickel
ferrite is found to be more as compared to its bulk counterpart. The frequency variation dielectric
permittivity is well fitted with the modified Debye formula, which suggests the presence of multiple
relaxation processes. The temperature dependent ac conductivity follows Jonscher’s universal power
law and reveals the presence of multiple transport mechanisms from small polaron hopping (SPH) to
correlated barrier hopping (CBH) mechanism near 200 °C. The estimated values of Mott parameters
are found to be satisfactory. Thermally activated relaxation phenomena have been confirmed by
scaling curves of imaginary impedance (Z) andmodulus (M). The comparison between the Z and
M spectra indicates that both long-range and short-rangemovement of charge carriers contribute to
dielectric relaxation with short-range charge carriers predominating at low temperatures while longrange
charge carriers are dominating at high temperatures. Analysis of the semicircular arcs of Nyquist
plot indicates the presence of grain boundary contribution to the electrical conduction process for the
nanocrystalline sample at high temperatures. The non-Debye type of relaxation has been examined by
stretching exponential factor (β) which has been estimated by fitting the modifiedKWW
(Kohlrausch-Williams-Watts) equation to the imaginary electric modulus curve. The value of β is
found to be strongly temperature dependent and its value for the nanocrystalline sample is less than
that of the bulk system which is explained on the basis of dipole-dipole interaction.
Temperature, acceptor concentration and donor concentration dependency of ele...IJAMSE Journal
Mobility is an important factor to determine the speed of an electronic device. Devices composed of electronic materials with higher mobility are able to achieve higher speed. It is therefore favourable to maximize the mobility. In this paper, we have chosen GaN and GaP as semiconductor material and Low-field electron mobility has been calculated in bulk and wurzite phase GaN and GaP. The dependency of mobility upon temperature is shown. Beside this, dependency of mobility upon acceptor concentration and donor concentration are also shown.
Hot hole transfer from Ag nanoparticles to multiferroic YMn2O5 nanowires enab...Pawan Kumar
Plasmonic hot carriers with a nonthermal distribution of kinetic energies have opened up new avenues in photovoltaics, photodetection and photocatalysis. While several articles have reported ultrafast hot electron injection from coinage metals into n-type semiconductors across Schottky barriers and efficient subsequent utilization of injected hot electrons, reports of hot hole harvesting are comparatively rare due to the difficulty in forming Schottky junctions between p-type semiconductors and high work function metals. In this communication, we report the fabrication, characterization and theoretical calculations of a novel integrated multiferroic-plasmonic system comprising YMn2O5 nanowires decorated on their surface with Ag nanoparticles (NPs). A Schottky barrier for holes exists at the YMn2O5-Ag hetero-interface and hot holes were injected from Ag across this barrier. The synthesized hybrid along with bare Ag NPs were tested for Raman surface photocatalytic reduction of 4-NBT (4-nitrobenzenethiol) to DMAB (p, p′-dimercaptoazobenzene) where the composite demonstrated superior activity compared to the bare metal. Ultraviolet photoelectron spectroscopy (UPS) revealed a significantly reduced work function of the composite compared to the pristine Ag, indicative of more energetic hot electrons on the surface of the composite required for efficient photoreduction. Density functional theory (DFT)-based calculations revealed localization of molecular orbitals supportive of a possible hole transfer from YMn2O5 to Ag and a reorganization of electronic states beneficial for plasmon-induced charge carrier enhancement. DFT results also indicated a purely electronic contribution to the ferroelectric polarization of YMn2O5 over and above the ionic contribution, which originated from the magnetic polarization of O 2p states.
Fabrication and studying the dielectric properties of (polystyrene-copper oxi...journalBEEI
The preparation of (polystyrene-copper oxide) nanocomposites have been investigated for piezoelectric application. The copper oxide nanoparticles were added to polystyrene by different concentrations are (0, 4, 8 and 12) wt.%. The structural and A.C electrical properties of (PS-CuO) nanocomposites were studied. The results showed that the dielectric constant and dielectric loss of (PS-CuO) nanocomposites decrease with increase in frequency. The A.C electrical conductivity increases with increase in frequency. The dielectric constant, dielectric loss and A.C electrical conductivity of polystyrene increase with increase in copper oxide nanoparticles concentrations. The results of piezoelectric application showed that the electrical resistance of (PS-CuO) nanocomposites decreases with increase in pressure.
the effect of nickel incorporation on some physical properties of epoxy resinINFOGAIN PUBLICATION
The J-E characteristics of samples of epoxy resins mixed with nickel powder in different concentrations have been tested and a log-log straight line behaviour in both the low- and high field regions is observed. Ni-concentration has significant influence on the calculated constants of the J-E relationship. The d.c. electrical resistivity (ρ) of the samples are measured from the room temperature up to about 400 K. The variation of ρ with T obeys the exponential relation of ordinary dielectrics in three temperature regions. The parameters characterizing the ρ -T dependence change considerably with Ni-concentration. Due to the existence of nickel in different concentration a "true" compensation effect is observed with three characteristic compensation temperatures. The mechanical hardness of the samples was investigated as a function of Ni-concentration.
Review on Molecular Dynamics Simulations of Effects of Carbon Nanotubes (CNTs...LidaN16
Abstract: Due to the unique properties of carbon nanotubes (CNTs), the electrical and thermal
conductivity of CNT-modified polymeric composites (CNTMPCs) can be manipulated and depend
on several factors. There are many factors that affect the thermal and electrical conductivity of
CNTs and CNTMPCs, such as chirality, length, type of CNTs, fabrication, surface treatment, matrix
and interfacial interaction between the matrix and reinforcement (CNTs). This paper reviews the
research on molecular dynamics (MD) simulations of the effects of some factors affecting the thermal
and electrical conductivity of CNTs and CNTMPCs. First, the chirality dependence of the thermal
and electrical conductivity of single-walled carbon nanotubes (SWNTs) was analyzed. The effect
of chirality on the conductivity of short-length CNTs is greater than that of long-length CNTs, and
the larger the chiral angle, the greater the conductivity of the CNTs. Furthermore, the thermal and
electrical conductivity of the zigzag CNTs is smaller than that of the armchair one. Therefore, as
the tube aspect ratio becomes longer and conductivity increases, while the effect of chirality on the
conductivity decreases. In addition, hydrogen bonding affects the electrical and thermal conductivity
of the CNTMPCs. The modeling of SWNTs shows that the thermal and electrical conductivity
increases significantly with increasing overlap length. MD simulations can be effectively used to
design highly conductive CNTMPCs with appropriated thermal and electrical properties. Since
there are too many factors affecting the thermal and electrical conductivity of CNTMPCs, this paper
only reviews the effects of limited factors on the thermal and electrical conductivity of CNTs and
CNTMPCs based on MD simulations, and further detailed studies are required.
Keywords: carbon nanotubes (CNTs); hydrogen bonding; CNT-modified polymeric composites
(CNTMPCs); chirality; aspect ratio; molecular dynamics (MD) simulation
Impact of CuS counter electrode calcination temperature on quantum dot sensit...TELKOMNIKA JOURNAL
In place of the commercial Pt electrode used in quantum sensitized solar cells, the low-cost CuS cathode is created using electrophoresis. High resolution scanning electron microscopy and X-ray diffraction were used to analyze the structure and morphology of structural cubic samples with diameters ranging from 40 nm to 200 nm. The conversion efficiency of solar cells is significantly impacted by the calcination temperatures of cathodes at 100 °C, 120 °C, 150 °C, and 180 °C under vacuum. The fluorine doped tin oxide (FTO)/CuS cathode electrode reached a maximum efficiency of 3.89% when it was calcined at 120 °C. Compared to other temperature combinations, CuS nanoparticles crystallize at 120 °C, which lowers resistance while increasing electron lifetime.
In place of the commercial Pt electrode used in quantum sensitized solar cells, the low-cost CuS cathode is created using electrophoresis. High resolution scanning electron microscopy and X-ray diffraction were used to analyze the structure and morphology of structural cubic samples with diameters ranging from 40 nm to 200 nm. The conversion efficiency of solar cells is significantly impacted by the calcination temperatures of cathodes at 100 °C, 120 °C, 150 °C, and 180 °C under vacuum. The fluorine doped tin oxide (FTO)/CuS cathode electrode reached a maximum efficiency of 3.89% when it was calcined at 120 °C. Compared to other temperature combinations, CuS nanoparticles crystallize at 120 °C, which lowers resistance while increasing electron lifetime.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
The Statutory Interpretation of Renewable Energy Based on Syllogism of Britis...AI Publications
The current production for energy consumption generates harmful impacts of carbon dioxide to the environment causing instability to sustainable development goals. The constitutional reforms of British Government serve to be an important means of resolving any encountered incompatibilities to political environment. This study aims to evaluate green economy using developed equation for renewable energy towards political polarization of corporate governance. The Kano Model Assessment is used to measure the equivalency of 1970 Patents Act to UK Intellectual Property tabulating the criteria for the fulfillment of sustainable development goals in respect to the environment, artificial intelligence, and dynamic dichotomy of administrative agencies and presidential restriction, as statutory interpretation development to renewable energy. The constitutional forms of British government satisfy the sustainable development goals needed to fight climate change, advocate healthy ecosystem, promote leadership of magnates, and delegate responsibilities towards green economy. The presidential partisanship must be observed to delineate parties of concerns and execute the government prescriptions in equivalence to the dichotomous relationship of technology and the environment in fulfilling the rights and privileges of all citizens. Hence, the political elites can execute corporate governance towards sustainable development of renewable energy promoting environmental parks and zero emission target of carbon dioxide discharges. The economic theory developed in statutory interpretation for renewable energy serves as a tool to reduce detrimental impacts of carbon dioxide to the environment, mitigate climate change, and produce artefacts of bioenergy and artificial intelligence promoting sustainable development. It is suggested to explore other vulnerabilities of artificial intelligence to prosper economic success.
Enhancement of Aqueous Solubility of Piroxicam Using Solvent Deposition SystemAI Publications
Piroxicam is a non-steroidal anti-inflammatory drug that is characterized by low solubility-high permeability. The present study was designed to improve the dissolution rate of piroxicam at the physiological pH's through its increased solubility by using solvent deposition system.
Analysis of Value Chain of Cow Milk: The Case of Itang Special Woreda, Gambel...AI Publications
Ethiopia has a long and rich history of dairy farming, which was mostly carried out by small and marginal farmers who raised cattle, camels, goats, and sheep, among other species, for milk. Finding the Itang Special Woreda cow milk value chain is the study's main goal. In order to gather primary data, 204 smallholder dairy farmer households were randomly selected, and the market concentration ratio was calculated using 20 traders. Descriptive statistics, econometric models, and rank analysis were used to achieve the above specified goals. Out of all the participants in the milk value chain, producers, cafés, hotels, and dairy cooperatives had the largest gross marketing margins, accounting for 100% of the consumer price in channels I and II, 55% in channels III and V, and 25.5% in channels V. The number of children under five, the number of milking cows owned, the amount of money from non-dairy sources, the frequency of extension service contacts, the amount of milk produced each day, and the availability of market information were found to have an impact on smallholders' involvement in the milk market. Numerous obstacles also limited the amount of milk produced and marketed. The poll claims that general health issues, sickness, predators, and a lack of veterinary care are plaguing farmers. In order to address the issue of milk perishability, the researchers recommended the host community and organization to construct an agro milk processor, renovate the dairy cooperative in the study region, and restructure the current conventional marketing to lower the transaction and cost of milk marketing.
Minds and Machines: Impact of Emotional Intelligence on Investment Decisions ...AI Publications
In the evolving landscape of financial decision-making, this study delves into the intricate relationships among Emotional Intelligence (EI), Artificial Intelligence (AI), and Investment Decisions (ID). By scrutinizing the direct influence of human emotional intelligence on investment choices and elucidating the mediating role of AI in this process, our research seeks to unravel the complex interplay between minds and machines. Through empirical analysis, we reveal that EI not only directly impacts ID but also exerts its influence indirectly through AI-mediated pathways. The findings underscore the pivotal role of emotional awareness in investor decision-making, augmented by the technological capabilities of AI. It suggests that most investors are influenced by the identified emotional intelligence when making investment decisions. Furthermore, AI substantially impacts investors' decision-making process when it comes to investing; nevertheless, AI partially mediates the relationship between emotional intelligence and investment decisions. This nuanced understanding provides valuable insights for financial practitioners, policymakers, and researchers, emphasizing the need for holistic strategies that integrate emotional and technological dimensions in navigating the intricacies of modern investment landscapes. As the synergy between human intuition and artificial intelligence becomes increasingly integral to financial decision-making, this study contributes to the ongoing discourse on the symbiotic relationship between minds and machines in investments.0
Bronchopulmonary cancers are common cancers with a poor prognosis. It is the leading cause of death by cancer in Algeria and in the world. Behind this unfavorable prognosis hides numerous disparities according to age, sex, and exposure to risk factors, ranking 4th among incident cancers and developing countries including Algeria, all sexes combined. It ranks 2nd cancers in men and 3rd among women. Whatever the age observed, the incidence of this cancer is higher in men than in women, however the gap is narrowing to the detriment of the latter. The results of scientific research agree to relate trends in incidence and mortality rates to tobacco consumption, including passive smoking. Furthermore, other risk factors are mentioned such as exposure to asbestos in the workplace or to radon for the general population, or even genetic predisposition. However, the weight of these etiological and/or predisposing factors is in no way comparable to that of tobacco in the genesis of lung cancer and the resulting mortality. We provide a literature review in our article on the descriptive and analytical epidemiology of lung cancer.
Further analysis on Organic agriculture and organic farming in case of Thaila...AI Publications
The objective of this paper is to present Further analysis on Organic agriculture and organic farming in case of Thailand agriculture and enhancing farmer productivity. In view of the demand for organic fertilizers, efforts should also be made to enhance and to develop more effective of compost, bio-fertilizer, and bio-pesticides currently used by farmers. Likewise, emphasis should also be laid on the cultivation of legumes and other crops that can enhance the fertility of the soil, as practiced by farmers in many developing countries to fertilize their lands. On the other hand, most of the farmers who practice this farm system found that they are adopting a number of SLMs and interested in joining the meeting or training to gain more and more knowledge.
Current Changes in the Role of Agriculture and Agri-Farming Structures in Tha...AI Publications
The objective os this study is to present Current Changes in the Role of Agriculture and Agri-Farming Structures in Thailand and Vietnam with SLM practices. Farmer’s adoption and investment in SLM is a key for controlling land degradation, enhancing the well-being of society, and ensuring the optimal use of land resources for the benefit of present and future generations (World Bank, 2006; FAO, 2018). And agriculture remains an essential element of lives of many farmers in term of the strong cultural and symbolic values that attach current working generation to do and to spend time for it but not intern of income generating.
Growth, Yield and Economic Advantage of Onion (Allium cepa L.) Varieties in R...AI Publications
Haphazard and low soil fertility, low yielding verities and poor agronomic practices are among the major factors constraining onion production in the central rift valley of Ethiopia. Therefore, a field experiment was conducted in East Showa Zone of Adami Tulu Jido Combolcha district in central rift valley areas at ziway from October 2021 to April 2022 to identify appropriate rate of NPSB fertilizer and planting pattern of onion varieties. The experiment was laid out in split plot design of factorial arrangement in three replications. The main effect of NPSB blended fertilizer rates and varieties (red coach and red king) significantly (p<0.01) influenced plant height, leaf length, leaf diameter, leaf number and fresh leaf weight, shoot dry matter per plant, and harvest index. Total dry biomass, bulb diameter, neck diameter, average fresh bulb weight, bulb dry matter, marketable bulb yield, and total bulb yield were significantly (p<0.01) influenced only by the main effect of NPSB blended fertilizer rates. In addition, unmarketable bulb yield was statistically significantly affected (p≥0.05) by the blended fertilizer rates and planting pattern. Moreover, days to 90% maturity of onion was affected by the main factor of NPSB fertilizer rate, variety and planting pattern. The non-fertilized plants in the control treatment were inferior in all parameters except unmarketable bulb yield and harvest index. Significantly higher marketable bulb yield (41 t ha-1) and total bulb yield (41.33 t ha-1) was recorded from 300 kg ha-1 NPSB blended fertilizer rate applied. Double row planting method and hybrid red coach onion variety had also gave higher growth and yields. The study revealed that the highest net benefit of Birr, 878,894 with lest cost of Birr 148,006 by the combinations of 150 kg blended NPSB ha-1 with double row planting method (40cm*20cm*7cm) and red coach variety which can be recommendable for higher marketable bulb yield and economic return of hybrid onion for small scale farmers in the study area. Also, for resource full producers (investors), highest net benefit of Birr 1,205,372 with higher cost (159,628 Birr) by application of 300 kg NPSB ha-1 is recommended as a second option. However, the research should be replicated both in season and areas to more verify the recommendations.
Evaluation of In-vitro neuroprotective effect of Ethanolic extract of Canariu...AI Publications
The ethanolic extract of canarium solomonense leaves (ecsl) was studied for its neuroprotective activity. The neuroprotective activity of ECSL was found to have a significant impact on neuronal cell death triggered by hydrogen peroxide (MTT assay) in human SH-SY5Y neuroblastoma cells. Scopolamine, a muscarinic receptor blocker, is frequently used to induce cognitive impairment in laboratory animals. Injections of scopolamine influence multiple cognitive functions, including motor function, short-term memory, and attention. Using the Morris water maze, the Y maze, and the passive avoidance paradigm, memory enhancing activity in scopolamine-induced amnesic rats was evaluated. Using the Morris water maze, the Y maze, and the passive avoidance paradigm, ECSL was found to have a substantial effect on the memory of scopolamine- induced amnesic rats. Our experimental data indicated that ECSL can reverse scopolamine induced amnesia and assist with memory issues.
The goal of neuroprotection is to shield neurons against damage, whether that damage is caused by environmental factors, pathogens, or neurodegenerative illnesses. Inhibiting protein-based deposit buildup, oxidative stress, and neuroinflammation, as well as rectifying abnormalities of neurotransmitters like dopamine and acetylcholine, are some of the ways in which medicinal herbs have neuroprotective effects [1-3]. This review will focus on the ways in which medicinal herbs may protect neurons.
A phytochemical and pharmacological review on canarium solomonenseAI Publications
The genus Canarium L. consists of 75 species of aromatic trees which are found in the rainforests of tropical Asia, Africa and the Pacific. The medicinal uses, botany, chemical constituents and pharmacological activities are now reviewed. Various compounds are tabulated according to their classes their structures are given. Traditionally canarium solomonense have been used to treat a broad array of illnesses. Pharmacological actions for canarium solomonense as discussed in this review include antibacterial, antimicrobial, antioxidant, anti-inflammatory, hepatoprotective and antitumor activity.
Influences of Digital Marketing in the Buying Decisions of College Students i...AI Publications
This research investigates the influence of digital marketing channels on purchasing decisions among college students in Ramanathapuram District. The study highlights that social media marketing, online advertising, and mobile marketing exhibit substantial positive effects on purchase decisions. However, email marketing's impact appears to be more complex. Moreover, the study explores how demographic variables like gender and academic level shape these effects. Notably, freshman students display varying susceptibility to specific digital marketing messages compared to their junior, senior, or graduate counterparts. These findings offer crucial insights for marketers aiming to tailor their strategies effectively to the preferences and behaviors of college students. By understanding the differential impacts of various digital marketing channels and considering demographic nuances, marketers can refine their approaches, optimize engagement, and ultimately enhance the effectiveness of their campaigns in targeting this demographic.
A Study on Performance of the Karnataka State Cooperative Agriculture & Rural...AI Publications
The Karnataka State Co-operative Agriculture and Rural Development Bank Limited is the apex bank of all the primary co-operative agriculture and rural development banks in the state. All the PCARD Banks in the state are affiliated to it. The KSCARD Bank provides financial accommodation to the PCARD Banks for their lending operations. In order to quick sanction and disbursement of loans and supervision over the PCARD Banks the KSCARD Bank has opened district level branches. Bank has established Women Development Cell to promote entrepreneurship among women in 2005. The Bank is identifying women borrowers in the rural areas by assigning suitable projects to motivate their self-confidence to lead independent life. Progress made in financing women entrepreneurs women.
Breast hamartoma is a rare, well-circumscribed, benign lesion made up of a variable quantity of glandular, adipose and fibrous tissue. This is a lesion that can affect women at any age from puberty. With the increasingly frequent use of imaging methods such as mammography and ultrasound as well as breast biopsy, cases of hamartoma diagnosed are increasing. The diagnosis of these lesions is made by mammography. The histological and radiological aspects are variable and depend on its adipose tissue content. The identification of these lesions is important in order to avoid surgical excisions. We report radio-clinical and pathological records of breast hamartoma.
A retrospective study on ovarian cancer with a median follow-up of 36 months ...AI Publications
Ovarian cancer is relatively common but serious and has a poor prognosis. The aim of this study is to highlight the epidemiological, diagnostic, therapeutic and evolutionary aspects of this malignant pathology managed at the Bejaia university hospital center. This is a retrospective and descriptive study over a period of 3 years (2019 - 2022) carried out on 20 patients who developed ovarian cancer. The average age of the patients was 50 years old, 53.23% of whom were over 45 years old. The CA-125 blood test was positive in 18 out of 20 patients. The tumors were discovered on ultrasound in 87.10% of cases and at laparotomy in 12.90%. Total hysterectomy with bilateral adnexectomy was the most performed procedure (64.52%). The early postoperative course was simple. 15 patients underwent second look surgery (16.13%) for locoregional recurrences. Epithelial tumors were the most frequent histological type (93.55%), including 79% in the advanced stage ( IIIc -IV) and 21% in the early stage (Ia- Ib ). Adjuvant chemotherapy was administered in 80% of patients. With a median follow-up of 36 months, 2 patients were lost to follow-up. The evolution was favorable in 27.42% and in 25.81% deaths occurred late postoperatively. Ovarian cancer is not common but serious given the advanced stages and the high rate of late postoperative deaths which were largely observed in patients deprived of adequate neoadjuvant or adjuvant chemotherapy.
More analysis on environment protection and sustainable agriculture - A case ...AI Publications
This study presents a case of tea and coffee crops , esp. environment protection and sustainable agriculture in Son La and Thai Nguyen of Vietnam. Research results show us that The process of having an agricultural product goes through many steps such as planting, planning, harvesting, packing, transporting, storing and distributing. - The State adopts policies to encourage innovation of agricultural production models and methods towards sustainability, adapting to climate change, saving water, and limiting the use of inorganic fertilizers and pesticides. chemicals and products for environmental treatment in agriculture; develop environmentally friendly agricultural models. Our research limitation is that we can expand for other crops, industries and markets as well.
Assessment of Growth and Yield Performance of Twelve Different Rice Varieties...AI Publications
The present investigation entitled “Assessment of growth and yield performance of twelve different rice varieties under north Konkan coastal zone of Maharashtra” was carried out during the kharif season of the year 2021 and 2022 on the field of ASPEE, Agricultural Research and Development Foundation, Tansa Farm, At Nare, Taluka Wada, District Palghar, Maharashtra, India. The experiment was laid out in Randomized Block Design (RBD). The twelve varieties namely Zini, Jaya, Dandi, Rahghudya, Govindbhog, Dangi, Gurjari, VNR-7, VNR-8, VNR-9, Karjat-3, and Karjat-5 were replicated thrice. The plant height (cm), number of tillers per plant, number of panicles per plant, number of panicles (m²), and length of panicle (cm) were noted to the maximum with cv. “VNR-7”. The highest number of seeds per panicle, test weight (gm), grain yield (q/ha), and straw yield (q/ha) were recorded with the cv. “VNR-7”. While the lowest number of days to 50% flowering was also recorded with cv. “VNR-7” during the year 2021 and 2022.
Cultivating Proactive Cybersecurity Culture among IT Professional to Combat E...AI Publications
In the current digital landscape, cybercriminals continually evolve their techniques to execute successful attacks on businesses, thus posing a great challenge to information technology (IT) professionals. While traditional cybersecurity approaches like layered defense and reactive security have helped IT professionals cope with traditional threats, they are ineffective in dealing with evolving cyberattacks. This paper focuses on the need for a proactive cybersecurity culture among IT professionals to enable them combat evolving threats. The paper emphasis that building a proactive security approach and culture can help among IT professionals anticipate, identify, and mitigate latent threats prior to them exploiting existing vulnerabilities. This paper also points out that as IT professionals use reactive security when dealing with traditional attacks, they can use it collaboratively with proactive security to effectively protect their networks, data, and systems and avoid heavy costs of dealing with cyberattack’s aftermaths and business recovery.
The Impacts of Viral Hepatitis on Liver Enzymes and BilrubinAI Publications
Viral hepatitis is an infection that causes liver inflammation and damage. Several different viruses cause hepatitis, including hepatitis A, B, C, D, and E. The hepatitis A and E viruses typically cause acute infections. The hepatitis B, C, and D viruses can cause acute and chronic infections. Hepatitis A causes only acute infection and typically gets better without treatment after a few weeks. The hepatitis A virus spreads through contact with an infected person’s stool. Protection by getting the hepatitis A vaccine. Hepatitis E is typically an acute infection that gets better without treatment after several weeks. Some types of hepatitis E virus are spread by drinking water contaminated by an infected person’s stool. Other types are spread by eating undercooked pork or wild game. Hepatitis B can cause acute or chronic infection. Recommendation for screening for hepatitis B in pregnant women or in those with a high chance of being infected. Protection from hepatitis B by getting the hepatitis B vaccine. Hepatitis C can cause acute or chronic infection. Doctors usually recommend one-time screening of all adults ages 18 to 79 for hepatitis C. Early diagnosis and treatment can prevent liver damage. The hepatitis D virus is unusual because it can only infect those who have a hepatitis B virus infection. A coinfection occurs when both hepatitis D and hepatitis B infections at the same time. A superinfection occurs already have chronic hepatitis B and then become infected with hepatitis D. The aim of this study is to find the effect of each type of viral hepatitis on the bilirubin (TB , DSB) , and liver enzymes; AST, ALT, ALP,GGT among viral hepatitis patients. 200 patients were selected from the viral hepatitis units in the central public health laboratory in Baghdad city, all the chosen cases were confirmed as a positive samples , they are classified into four equal group each with fifty individual and with a single serological viral hepatitis type either; anti-HAV( IgM ) , HBs Ag , anti-HCV ,or anti-HEV(IgM ). All patients were tested for; serum bilirubin ( TB ,D.SB ) , AST , ALT , ALP , GGT. Another fifty quite healthy and normal person was selected as a control group for comparison. . Liver enzymes and bilirubin changes are more pronounced in HAV, HEV than HCV and HBVAST and ALT lack some sensitivity in detecting HCV ,HBV and mild elevations of ALT or AST in asymptomatic patients can be evaluated efficiently by considering ,hepatitis B, hepatitis C. ALT is generally a more sensitive indicator of acute liver cell damage than AST, It is relatively specific for hepatocyte necrosis with a marked elevations in viral hepatitis. Liver enzymes and bilirubin changes are more pronounced in HAV, HEV than HCV and HBV.AST and ALT lack some sensitivity in detecting HCV ,HBV and mild elevations of ALT or AST in asymptomatic patients can be evaluated efficiently by considering ,hepatitis B, hepatitis C. ALT is generally a more sensitive indicator of acute liver
Determinants of Women Empowerment in Bishoftu Town; Oromia Regional State of ...AI Publications
The purpose of this study was to determine the status of women's empowerment and its determinants using women's asset endowment and decision-making potential as indicators. To determine representative sample size, this study used a two-stage sampling technique, and 122 sample respondents were selected at random. To analyze the data in this study, descriptive statistics and a probit model were used. The average women's empowerment index was 0.41, indicating a relatively lower status of women's empowerment in the study area. According to the study's findings, only 40.9% of women were empowered, while the remaining 59.1% were not. The probit model results show that women's access to the media, women's income, and their husbands' education status have a significant and positive impact on the status of women's empowerment, while the family size of households has a negative impact. As a result, it is important to enhance women's access to the media and income, promote family planning and contraception, and improve men's educational status in order to improve the status of women's empowerment.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
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Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
2. Kasala Suresha
International Journal of Chemistry, Mathematics and Physics (IJCMP), Vol-6, Issue-1 (2022)
www.aipublications.com Page | 2
scattering rates for GaAs, InGaAs and InSb quantum wires
is studied for electron transport along the [100],[110] and
[111] directions as well as for both free and clamped
boundary conditions. Using a parameterization of the
acoustic phonon velocities, the directional dependence of
both the longitudinal and transverse velocities and is taken
into account for each of the cases considered. The
principal findings in the present paper are that acoustic
phonon confinement effects may be crucial for calculating
accurate low-energy electron scattering rates in
semiconductor quantum wires and that there may be
significant directional dependence in the subject scattering
rates.
The most efficient thermoelectrics have historically
been heavily doped semiconductors because the Pauli
principle restricts the heat carrying electrons to be close to
the Fermi energy [14] for metals. The Wiedemann–Franz
law, , where is the electronic contribution
to , constrains , where is the Seebeck
coefficient (or thermoelectric power), and and are the
electrical and thermal conductivities, respectively.
Semiconductors have a lower density of carriers, leading
to larger values and a value that is dominated by
phonons , implying that the electrical and thermal
conductivities are somewhat decoupled [14]. can be
reduced by using bulk semiconductors of high atomic
weight, which decreases the speed of sound. However, this
strategy has not yet produced materials with >1. For a
metal or highly doped semiconductor, S is proportional to
the energy derivative of the density of electronic states. In
low-dimensional (nanostructured) systems the density of
electronic states has sharp peaks [15-17] and, theoretically,
a high thermopower. Harnessing this electronic effect to
produce high materials has had only limited success
[18-19]. However, optimization of the phonon dynamics
and heat transport physics in nanostructured systems has
yielded results [20-21]. Nanostructures may be prepared
with one or more dimensions smaller than the mean free
path of the phonons and yet larger than that of electrons
and holes. This potentially reduces without decreasing
[22]. Bulk silicon (Si) is a poor thermoelectric ( at
300K) [23], and this phonon physics is important for our
Si nanowires, in which the electronic structure remains
bulk-like.
The thermoelectric properties of any new materials
can be realized by studying with its possible applications
in thermoelectric devices as their efficiency depends upon
the thermoelectric figure of merit Z, Phonon-drag
thermopower as well as electron diffusion thermopower.
Theoretically is studied in graphene [24], 3D Dirac
semimetals [25]. Diffusion thermopower is
predicted to show linear dependence agreeing with Mott
formula and experimental results. The measured value of
at room temperature is about 62V/K. In the
present theoretical work, we tried to show the comparison
between existing experimental observations [26] with
theory and obtained a good agreement with experimental
thermopower of Si nanowire in the overall temperature
range.
II. THEORY
It is assumed that, the temperature is high enough to
maintain an equipartition regime of electron-phonon
interaction, in which the number of occupation of the
phonon modes contributing to carrier diffusion and phonon
drag effect. The most efficient Thermoelectrics have been
heavily doped semiconductors because the Pauli principle
restricts the heat carrying electrons to within of the
Fermi level for metals. Semiconductors have a lower
density of carriers, leasing to larger thermopower values
implying that the electrical and thermal conductivities are
somewhat decoupled. Thermal conductivity can be
reduced by using bulk semiconductors of high atomic
weight, which decreases the speed of sound. However, this
strategy has not yet produced materials with figure of
merit greater than unity. For metal or highly doped
semiconductors, thermoelectric power S is proportional to
the energy derivative of the density of electronic states. In
low-dimensional (nanostructured) systems the density of
electronic states has sharp peaks [17] and theoretically a
high thermopower.
We consider separately the electron diffusion
and phonon drag contribution to the thermopower
for the Si nanowire over the
temperature T from 50 K to 400K. Charge carriers
dissipate heat to the lattice through a process that first
involves momentum conserving (non-dissipative) electron-
phonon collisions. The phonons that contribute to phonon
drag cannot have a wavelength shorter than which is
determined by the size of the Fermi surface. Phonon drag
is observed in metals only at low temperature because the
Fermi surface is large and the heat carrying short-
wavelength phonons have short lifetime at lower
temperature (T < 20K). Umklapp (non-momentum-
conserving) phonon-phonon scattering processes
determine the rate of phonon heat dissipation. The Debye
energy sets the energy scale for umklapp scattering.
The number of umklapp phonons available to dissipate
3. Kasala Suresha
International Journal of Chemistry, Mathematics and Physics (IJCMP), Vol-6, Issue-1 (2022)
www.aipublications.com Page | 3
long wavelength phonons is given by Bose-Einstein
function
(1)
Leading to a scattering rate, , when , so
that because = 640K for Silicon, the Bose-
Einstein expression must be applied for K. The
electronic contribution is estimated using Mott
formula [27-28];
(2)
where the conductivity derivative equals the reciprocal of
the energy scale over which it varies.
For K, the experimental thermopower
data of silicon nanowire fit to the theoretical expression,
(3)
where , and are varied to obtain the best fit to
experimentally observed data [24].
III. RESULTS AND DISCUSSION
Using the above final expression (3) for thermopower,
we successfully explain the theoretical data with the
experimental observations [26]. Figure 1 shows the best fit
(black solid line) with the experimental data for the
temperature K by considering both contribution
of thermopower from electron diffusion and
phonon drag . To obtain a best fit, , and are
used as adjustable parameters. In our calculations, we used
= 0.337 V/K, = 22.1 V/K and = 534K. But for the
temperature below 200K, we didn’t get best with the
experimental data of thermopower. Since for lower
temperature K, the contribution towards
thermopower is only due to electron diffusion
thermopower. With the above mentioned adjustable
parameter , we will not observe best with the
experimental data. So we used adjustable parameter
=2.0 V/K to obtain a best fit in figure 1 (pink dash-dot
line) for the temperature below 200K where diffusion
thermopower is dominant mechanism. This is good
agreement with predicted linear temperature dependence
for less than Fermi energy, which is about 200 meV
agreeing with Mott formula and experimental results [29].
50 100 150 200 250 300 350 400
0
100
200
300
400
500
50 100 150 200 250 300 350 400
0
100
200
300
400
500
Temperature (K)
Sdiff
Sdrag
S=Sdiff
+Sdrag
Sdiif
a=2.0V/K
S
(
V/K)
Experimental data
Fig. 1: Comparison of experimental data (solid dots) [26]
with theory. Blue dash-dot-dot line represents for .
Red dash line for and black solid line represent for
total . Pink dash-dot line represents for with =2.0
V/K.
Figure 2 shows the comparison between
experimental observations with theory. In this figure we
obtain a best fit over the entire temperature range from the
electron diffusion contribution only with adjustable
parameter =0.46 V/K. In this figure we don’t observe
contribution from phonon drag effect. The decrease of S to
zero as T tends to zero occurs because the phonon mean
free path reaches the sample size and the specific heat
tends to zero according to third law of thermodynamics. It
is also interesting to observe that a linear dependence of
carrier diffusion thermopower with temperature which
satisfies the experimental observations [29]. Without
considering the phonon drag effect mechanism, the
calculated values of diffusion thermopower contribution is
enough to get best fit with experimental observations.
4. Kasala Suresha
International Journal of Chemistry, Mathematics and Physics (IJCMP), Vol-6, Issue-1 (2022)
www.aipublications.com Page | 4
50 100 150 200 250 300 350 400
0
50
100
150
200
250
300
350
400
450
50 100 150 200 250 300 350 400
0
50
100
150
200
250
300
350
400
450
50 100 150 200 250 300 350 400
0
50
100
150
200
250
300
350
400
450
S
(
V/K)
Temperature (K)
Experimental data
Experimental data
a=0.4 V/K
Fig.2: Comparison of experimental data (diamonds and
triangles) [26] with theory. Solid line represent for
with =0.46 V/K.
IV. CONCLUSION
In this theoretical study, we conclude that our calculations
for thermopower in Silicon nanowire are in good
agreement with the experimental observations. At low
temperature, carrier diffusion thermopower shows a
dominant mechanism for thermopower with linear
temperature dependence. At higher temperature both
carrier diffusion and phonon drag effects are effective to
obtain a good agreement with the experimental
observations.
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