X-Ray Fluorescence (XRF) is an elemental analysis technique that identifies elements present in a sample by detecting the characteristic X-rays emitted by the sample when it is excited by a primary X-ray source or electron beam. Modern XRF instruments can rapidly analyze solids, liquids, and thin films to determine both major and trace elemental components without extensive sample preparation. XRF is based on the principle that bombarding a material with high-energy photons or electrons ejects inner shell electrons, producing element-specific fluorescent X-rays as the electron vacancies are filled.
Presentation on environmental science notesNeetuJoshi20
There are two main XRF methodologies - Energy Dispersive XRF (EDXRF) and Wavelength Dispersive XRF (WDXRF). Each method has its own advantages and disadvantages.
The range of detectable elements varies according to instrument configuration and set up, but typically EDXRF covers all elements from sodium (Na) to uranium (U), whilst WDXRF can extend this down to beryllium (Be). Concentrations can range from 100% down to ppm and in some cases sub-ppm levels. Limits of detection depend upon the specific element and the sample matrix, but as a general rule, heavier elements will have better detection limits.
XRF is widely used as a fast characterization tool in many analytical labs across the world, for applications as
Presentation on environmental science notesNeetuJoshi20
There are two main XRF methodologies - Energy Dispersive XRF (EDXRF) and Wavelength Dispersive XRF (WDXRF). Each method has its own advantages and disadvantages.
The range of detectable elements varies according to instrument configuration and set up, but typically EDXRF covers all elements from sodium (Na) to uranium (U), whilst WDXRF can extend this down to beryllium (Be). Concentrations can range from 100% down to ppm and in some cases sub-ppm levels. Limits of detection depend upon the specific element and the sample matrix, but as a general rule, heavier elements will have better detection limits.
XRF is widely used as a fast characterization tool in many analytical labs across the world, for applications as
In mineral science, there are several analytical instruments used for various purpose, viz…
Scanning electron microscopy
X-ray diffraction
Transmission electron microscopy
X-ray fluorescence
Flame atomic absorption spectroscopy
Electron microprobe analysis
Secondary ion mass spectrometry
Atomic force microscopy
Spectroscopy is the study of the interaction of electromagnetic radiation in all its forms with the matter. The interaction might give rise to electronic excitations, (e.g. UV), molecular vibrations (e.g. IR) or nuclear spin orientations (e.g. NMR). Thus Spectroscopy is the science of the interaction of energy, in the form of electromagnetic radiation (EMR), acoustic waves, or particle beams, with the matter.
Here in this article, the matter is studied in further detail.
Fluorescent activated cell sorting (FACS) is a specialized type of flow cytometry used for sorting and analyzing a heterogeneous mixture of cells into different sub- populations based on the specific light scattering and fluorescent characteristics (from the specific labels) of each cell.
SPECTROSCOPY is defined as the study of the interactions between radiations and matter as function of wavelength λ .
Interactions with particle radiation or a response of a material to an altering field
or varying frequency.
SPECTRUM : A plot of the response as a function of wavelength or more commonly frequency is referred to as spectrum.
SPECTROMETRY : It is measurement of these responses and an instrument which performs such measurements is a spectrophotometer or spectrograph, although
these terms are more limited in use to original field of optics from which the
concept sprang.
In mineral science, there are several analytical instruments used for various purpose, viz…
Scanning electron microscopy
X-ray diffraction
Transmission electron microscopy
X-ray fluorescence
Flame atomic absorption spectroscopy
Electron microprobe analysis
Secondary ion mass spectrometry
Atomic force microscopy
Spectroscopy is the study of the interaction of electromagnetic radiation in all its forms with the matter. The interaction might give rise to electronic excitations, (e.g. UV), molecular vibrations (e.g. IR) or nuclear spin orientations (e.g. NMR). Thus Spectroscopy is the science of the interaction of energy, in the form of electromagnetic radiation (EMR), acoustic waves, or particle beams, with the matter.
Here in this article, the matter is studied in further detail.
Fluorescent activated cell sorting (FACS) is a specialized type of flow cytometry used for sorting and analyzing a heterogeneous mixture of cells into different sub- populations based on the specific light scattering and fluorescent characteristics (from the specific labels) of each cell.
SPECTROSCOPY is defined as the study of the interactions between radiations and matter as function of wavelength λ .
Interactions with particle radiation or a response of a material to an altering field
or varying frequency.
SPECTRUM : A plot of the response as a function of wavelength or more commonly frequency is referred to as spectrum.
SPECTROMETRY : It is measurement of these responses and an instrument which performs such measurements is a spectrophotometer or spectrograph, although
these terms are more limited in use to original field of optics from which the
concept sprang.
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Hotel management involves overseeing all aspects of a hotel's operations to ensure smooth functioning and exceptional guest experiences. This multifaceted role includes tasks such as managing staff, handling reservations, maintaining facilities, overseeing finances, and implementing marketing strategies to attract guests. Effective hotel management requires strong leadership, communication, organizational, and problem-solving skills to navigate the complexities of the hospitality industry and ensure guest satisfaction while maximizing profitability.
Hamdard Laboratories (India), is a Unani pharmaceutical company in India (following the independence of India from Britain, "Hamdard" Unani branches were established in Bangladesh (erstwhile East Pakistan) and Pakistan). It was established in 1906 by Hakeem Hafiz Abdul Majeed in Delhi, and became
a waqf (non-profitable trust) in 1948. It is associated with Hamdard Foundation, a charitable educational trust.
Hamdard' is a compound word derived from Persian, which combines the words 'hum' (used in the sense of 'companion') and 'dard' (meaning 'pain'). 'Hamdard' thus means 'a companion in pain' and 'sympathizer in suffering'.
The goals of Hamdard were lofty; easing the suffering of the sick with healing herbs. With a simple tenet that no one has ever become poor by giving, Hakeem Abdul Majeed let the whole world find compassion in him.
They had always maintained that working in old, traditional ways would not be entirely fruitful. A broader outlook was essential for a continued and meaningful existence. their effective team at Hamdard helped the system gain its pride of place and thus they made an entry into an expansive world of discovery and research.
Hamdard Laboratories was founded in 1906 in Delhi by Hakeem Hafiz Abdul Majeed and Ansarullah Tabani, a Unani practitioner. The name Hamdard means "companion in suffering" in Urdu language.(itself borrowed from Persian) Hakim Hafiz Abdul Majeed was born in Pilibhit City UP, India in 1883 to Sheikh Rahim Bakhsh. He is said to have learnt the complete Quran Sharif by heart. He also studied the origin of Urdu and Persian languages. Subsequently, he acquired the highest degree in the unani system of medicine.
Hakim Hafiz Abdul Majeed got in touch with Hakim Zamal Khan, who had a keen interest in herbs and was famous for identifying medicinal plants. Having consulted with his wife, Abdul Majeed set up a herbal shop at Hauz Qazi in Delhi in 1906 and started to produce herbal medicine there. In 1920 the small herbal shop turned into a full-fledged production house.
Hamdard Foundation was created in 1964 to disburse the profits of the company to promote the interests of the society. All the profits of the company go to the foundation.
After Abdul Majeed's death, his son Hakeem Abdul Hameed took over the administration of Hamdard Laboratories at the age of fourteen.
Even with humble beginnings, the goals of Hamdard were lofty; easing the suffering of the sick with healing herbs. With a simple tenet that no one has ever become poor by giving, Hakeem Abdul Majeed let the whole world find compassion in him. Unfortunately, he passed away quite early but his wife, Rabia Begum, with the support of her son, Hakeem Abdul Hameed, not only kept the institution in existence but also expanded it. As he grew up, Hakeem Abdul Hameed took on all responsibilities. After helping with his younger brother's upbringing and education, he included him in running the institution. Both brothers Hakeem Abdul Hameed and Hakim Mohammed
1. X-Ray Fluorescence (XRF)
K V GOPINATH M Pharm PhD,CPhT
Tirumala Tirupati Devasthanams
TIRUPATI
e-mail:gopinath.karnam@gmail.com
2. Introduction
X-ray fluorescence (XRF) spectrometry is an elemental analysis
technique with broad application in science and industry.
XRF is routinely used for the simultaneous determination of
elemental composition and film thickness.
Modern XRF instruments are capable of analyzing solid, liquid, and
thin-film samples for both major and trace (ppm-level) components.
The analysis is rapid and usually sample preparation is minimal or
not required at all.
3. Principle
XRF is based on the principle that individual atoms, when excited by
an external energy source, emit X-ray photons of a characteristic
energy or wavelength. By counting the number of photons of each
energy emitted from a sample, the elements present may be identified
and quantitated.
Theory
When an electron beam of high energy strikes a material, one
of the results of the interaction is the emission of photons which have
a broad continuum of energies. This radiation, called “braking
radiation”, is the result of the deceleration of the electrons inside the
material. The bremsstrahlung continuum is illustrated as a function of
electron acceleration voltages for a molybdenum target .
4. Theory of XRF
Another result of the interaction between the electron beam and the
material is the ejection of photoelectrons from the inner shells of the
atoms making up the material. These photoelectrons leave with a
kinetic energy (E-φ) which is the difference in energy between that
of the incident particle (E) and the binding energy (φ) of the atomic
electron. This ejected electron leaves a “hole” in the electronic
structure of the atom, and after a brief period, the atomic electrons
rearrange, with an electron from a higher energy shell filling the
vacancy. By way of this relaxation the atom undergoes fluorescence,
or the emission of an X-ray photon whose energy is equal to the
difference in energies of the initial and final states. Detecting this
photon and measuring its energy allows us to determine the element
and specific electronic transition from which it originated
5. Instrumentation
Most of the XRF instruments in use today fall into two categories:
energy-dispersive (ED) and wavelength-dispersive (WD)
spectrometers.
Within these two categories is a tremendous variety of differing
configurations, X-ray sources and optics, and detector technologies.
WD Spectrometers :The instrument operates based on the principle
of Bragg diffraction of a collimated X-ray beam, in this case the
beam emanating from the sample. A detector is angularly scanned
relative to the analyzing crystal, registering the spectrum.
Energy Dispersive (ED): The entire polychromatic spectrum from
the sample is incident upon a detector that is capable of registering
the energy of each photon that strikes it. The detector electronics and
data system then build the X-ray spectrum as a histogram, with
number of counts versus energy.
6. Instrumentation
1) X-ray irradiates specimen
2) Specimen emits characteristic
X-rays or XRF
3) Analyzing crystal rotates to
accurately reflect each
wavelength and satisfy
Bragg’s Law n =2dsin
ƛ θ
4) Detector measures position and
intensity of XRF peaks
5) XRF is diffracted by a
crystal at different θ to
separate X-ray l and to
identify elements
7. By Laue Method - To Determine the
Orientation of Single Crystals
Back-reflection Laue
Transmission Laue
9. Advantages of XRF
XRF is a versatile, rapid technique .
It is non destructive method of chemical analysis. Important as in
case of samples in limited amounts, or valuable or irreplaceable.
It is precise and with skilled operations it is accurate.
Applicable to a wide variety of samples from powders to liquids.
It is convenient and economical to use.
With the major input cost being the hardware itself, which averages
around $75,000 for a modern industrial-use spectrometer or
$125,000 for a research-quality instrument.
The instruments have few moving parts, tend to be low-maintenance,
and on a regular basis consume only liquid nitrogen and electricity.
10. Disadvantages
Disadvantages include fairly high limits of detection (LODs) when
compared to other methods.
Possibility of matrix effects, although these can usually be accounted
for using software-based correction procedures. LODs for graphite
furnace atomic absorption spectroscopy (GFAAS) beat XRF by
several orders of magnitude, but analyses can exhibit substantial
matrix effects. GFAAS is also relatively slow, with one element
determined at a time, and is destructive
PXRF instruments are capable of producing results comparable in
many ways to the lab-based XRF at a fraction of the cost. PXRF
instruments can be purchased for about $30,000 to $50,000 complete
with vacuum systems, sample changer, and accompanying
computer.
11. Applications of XRF
It is a method of elemental (metal and Non metal ) analysis with
atomic number greater than 12.
Quantitative analysis can be carried out by measuring the intensity of
fluorescence at the wavelength characteristics of the element being
determined, especially applicable to most of the element in the
periodic table.
In medicine
– Direct determination of sulfur in protein. The sulfur content of each of the many
different forms in which protein exists in human blood varies considerably.
– XRF indicates protein distribution and provides a diagnostic link for the medical
practitioner.
– Determination of chloride in blood serum
– Determination of strontium in blood serum and bone tissue
– Elemental analysis of tissues, bones and body fluids.
– It is used for determination of trace elements in plants and foods.
– It is used for detection of pesticides on fruits and herbal drugs