LIGHT MICROSCOPY by SIVASANGARI SHANMUGAM
The optical microscope, The functions of a light microscope is based on its ability to focus a beam of light through, which is very small and transparent, to produce an image.
Transmission electron microscopy (TEM)- by sivasangari Shanmugam. Transmission electron microscopy (TEM) is a technique used to observe the features of very small specimens.
LIGHT MICROSCOPY by SIVASANGARI SHANMUGAM
The optical microscope, The functions of a light microscope is based on its ability to focus a beam of light through, which is very small and transparent, to produce an image.
Transmission electron microscopy (TEM)- by sivasangari Shanmugam. Transmission electron microscopy (TEM) is a technique used to observe the features of very small specimens.
This presentation include information about electron microscope & types of electron microscope i.e. SEM (Scanning electron microscope) & TEM (Transmission electron microscope).
An electron microscope is a microscope that uses a beam of scattered electrons as a source of illumination. It is used to get information about structure, topology, morphology & composition of materials. It has many advantages. Basically there are 4 types of electron microscope but here we will discuss only 2 types.
Transmission electron microscopy is a microscopy technique in which a beam of electrons is transmitted through an ultra-thin specimen, interacting with the specimen as it passes through it. Its resolution & magnification is about 10,000,000x. There are 5 types of transmission electron microscope i.e. BFTEM (Bright field transmision electron microscope), DFTEM (Dark field transmission electron microscope), HRTEM (High resolution transmission electron microscope), EFTEM (Energy filtered transmission electron microscope), ED (Electron diffraction). there are 4 techniques of TEM i.e. negative staining, shadow casting, Freeze fracture replication, freeze etching. It has many applications e.g, for the study of Cancer research, virology, chemical industry, electronic structure etc.
A scanning electron microscope is a type of electron microscope that produces images of a sample by scanning it with a focused beam of electrons. Types of signals produce by SEM include secondary electrons, back scattered electrons, X-rays, light rays. There are many advantages of SEM e.g, Btter resolution, fast imaging easy to operate, work with low voltage etc.
The microscope has evolved a lot from the time of Leeuwenhoek. This presentation gives a brief overview about the types of microscope their principle of function and application.
Microscopy is the technical field of using microscopes to view objects and areas of objects that cannot be seen with the naked eye (objects that are not within the resolution range of the normal eye). There are three well-known branches of microscopy: optical, electron, and scanning probe microscopy, along with the emerging field of X-ray microscopy.
i am HAFIZ M WASEEM from mailsi vehari
bsc in science college multan pakistan
msc univesity of education lahore pakistan
i love pakistan and my teachers
Electron microscope, principle and applicationKAUSHAL SAHU
Introduction
History
Resolution &Magnification of
Electron microscope
Types of electron microscope
1) Transmission electron microscope (TEM)
- Structural parts of TEM
- Principle & Working of TEM
- Sample preparation for TEM
- Advantages & disadvantages of TEM
Scanning electron microscope (SEM)
- Structural parts of SEM
- Principle & Working of SEM
- Sample preparation for SEM
- Advantages & disadvantages of SEM
3) Scanning transmission electron microscope (STEM)
Applications of electron microscope
Conclusion
References
A scanning electron microscope is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. The electrons interact with atoms in the sample, producing various signals that contain information about the sample's surface topography and composition.
SEMs can magnify an object from about 10 times up to 300,000 times. A scale bar is often provided on an SEM image. From this the actual size of structures in the image can be calculated.
Microscopy - Magnification, Resolving power, Principles, Types and ApplicationsNethravathi Siri
Magnification, Resolving power, Principles and Applications of Simple, Compound, Stereozoom, Phase contrast, Fluorescent and Electron microscopes (TEM & SEM).
Microscopy is the technical field that uses microscopes to observe samples which are not in the resolution range of the normal-unaided eye.
during this ppt of microscopes we will be able to know
INTRODUCTION
DEFINITION
HISTORICAL BACKGROUND
VARIABLES USED IN MICROSCOPY
VARIOUS TYPES OF MICROSCOPES
COMPOUND MICROSCOPE - Structure and Function
USE OF MICROSCOPE
CARE OF MICROSCOPE
defintion
A microscope (Greek: micron = small and scopos = aim)
MICROSCOPE - An instrument for viewing objects that are too small to be seen by the naked or unaided eye
MICROSCOPY - The science of investigating small objects using such an instrument is called microscopy
170male reproductive systemmale reproductive system
xtestis is covered by three layers (from
outside to inwards):
̞visceral layer of tunica vaginalis:
̎it is lined by flat mesothelial cells.ons of seminiferous tubules lined by spermatogonia, primary and secondary
xThese tight junctions form the blood–testis
barrier.
xThe tight junction divides the intercellular
compartment between the Sertoli cells
into basal and luminal compartment.
xBasal compartment contains spermato
gonia and primary spermatocytes.
xLuminal compartment contains secondary
spermatocytes and spermatids (Fig. 19.5).
Functions of Sertoli Cells
xSertoli cells provide support and nutrition
to spermatogenic cells.
xThe bloodtestis barrier protects the
spermatogenic cells from the harmful
substances (antigens) of blood.
xThey phagocytose the residual bodies.
xSertoli cells secrete androgen-binding
protein (ABP), which concentrates the
testosterone.
xIn fetal testis, Sertoli cells produce anti
mullerian hormone, which inhibits the
development of mullerian duct.
xSertoli cells are nondividing cells, highly
resistant to infection, malnutrition, and
radiation.
xThese produce inhibin, which inhibits the
secretion of follicle-stimulating hormone
(FSH).
Interstitial Cells of Leydig
xThese are large polyhedral cells lying in
the connective tissue between seminif
erous tubules.
xThese are pale staining cells with eccen
tric nucleus and cytoplasm shows unique
needleshaped crystalline inclusion
(Reinke’s crystal).
spermatocytes, spermatids, and sperms are seen.
2.Sertoli cells are seen in between the spermatogenic cells.
3.Interstitial ces of Leydig are seen in between the seminiferous tubules.
xThey secrete testoster
̞tunica albuginea:
̎it is a thin layer of connective tissue
containing collagen, blood vessels,
and lymphatics.
̎along the posterior border, tunica
albuginea is thickened to form medi
astinum testis.
̎septa arising from the mediastinum
testis divide the substance of the
testis into 200 to 300 lobules.
̎each lobule contains one to four
seminiferous tubules.
̎seminiferous tubules contain coiled
part in the front and straight part
behind.
̎straight part enters the medi
astinum testis where it joins and
forms a network called as rete testis.
̎from the upper end of rete testis
12 to 14 efferent ductules arise and
enter the epididymis.
̞tunica vasculosa:
̎highly vascularized connective
tissue which covers the individual
lobule.
microscopic structure
oftestis
seminiferous tubule
xthere are 400 to 600 seminiferous tubules
in each testis.
xeach tubule is surrounded by a basal
lamina supported by connective tissue
which contains muscle-like myoid cells.
xcontraction of myoid cells helps to move
the spermatozoa along the tubule.
xeach seminiferous tubule is lined by
stratified seminiferous epithelium which
contains spermatogenic cells and sertoli
cells(figs. 19.2and19.3).
fig. 19.2diagram of testis (h&e pencil). h&e, hematoxylin and eosin. 3.Interstitia
This presentation include information about electron microscope & types of electron microscope i.e. SEM (Scanning electron microscope) & TEM (Transmission electron microscope).
An electron microscope is a microscope that uses a beam of scattered electrons as a source of illumination. It is used to get information about structure, topology, morphology & composition of materials. It has many advantages. Basically there are 4 types of electron microscope but here we will discuss only 2 types.
Transmission electron microscopy is a microscopy technique in which a beam of electrons is transmitted through an ultra-thin specimen, interacting with the specimen as it passes through it. Its resolution & magnification is about 10,000,000x. There are 5 types of transmission electron microscope i.e. BFTEM (Bright field transmision electron microscope), DFTEM (Dark field transmission electron microscope), HRTEM (High resolution transmission electron microscope), EFTEM (Energy filtered transmission electron microscope), ED (Electron diffraction). there are 4 techniques of TEM i.e. negative staining, shadow casting, Freeze fracture replication, freeze etching. It has many applications e.g, for the study of Cancer research, virology, chemical industry, electronic structure etc.
A scanning electron microscope is a type of electron microscope that produces images of a sample by scanning it with a focused beam of electrons. Types of signals produce by SEM include secondary electrons, back scattered electrons, X-rays, light rays. There are many advantages of SEM e.g, Btter resolution, fast imaging easy to operate, work with low voltage etc.
The microscope has evolved a lot from the time of Leeuwenhoek. This presentation gives a brief overview about the types of microscope their principle of function and application.
Microscopy is the technical field of using microscopes to view objects and areas of objects that cannot be seen with the naked eye (objects that are not within the resolution range of the normal eye). There are three well-known branches of microscopy: optical, electron, and scanning probe microscopy, along with the emerging field of X-ray microscopy.
i am HAFIZ M WASEEM from mailsi vehari
bsc in science college multan pakistan
msc univesity of education lahore pakistan
i love pakistan and my teachers
Electron microscope, principle and applicationKAUSHAL SAHU
Introduction
History
Resolution &Magnification of
Electron microscope
Types of electron microscope
1) Transmission electron microscope (TEM)
- Structural parts of TEM
- Principle & Working of TEM
- Sample preparation for TEM
- Advantages & disadvantages of TEM
Scanning electron microscope (SEM)
- Structural parts of SEM
- Principle & Working of SEM
- Sample preparation for SEM
- Advantages & disadvantages of SEM
3) Scanning transmission electron microscope (STEM)
Applications of electron microscope
Conclusion
References
A scanning electron microscope is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. The electrons interact with atoms in the sample, producing various signals that contain information about the sample's surface topography and composition.
SEMs can magnify an object from about 10 times up to 300,000 times. A scale bar is often provided on an SEM image. From this the actual size of structures in the image can be calculated.
Microscopy - Magnification, Resolving power, Principles, Types and ApplicationsNethravathi Siri
Magnification, Resolving power, Principles and Applications of Simple, Compound, Stereozoom, Phase contrast, Fluorescent and Electron microscopes (TEM & SEM).
Microscopy is the technical field that uses microscopes to observe samples which are not in the resolution range of the normal-unaided eye.
during this ppt of microscopes we will be able to know
INTRODUCTION
DEFINITION
HISTORICAL BACKGROUND
VARIABLES USED IN MICROSCOPY
VARIOUS TYPES OF MICROSCOPES
COMPOUND MICROSCOPE - Structure and Function
USE OF MICROSCOPE
CARE OF MICROSCOPE
defintion
A microscope (Greek: micron = small and scopos = aim)
MICROSCOPE - An instrument for viewing objects that are too small to be seen by the naked or unaided eye
MICROSCOPY - The science of investigating small objects using such an instrument is called microscopy
170male reproductive systemmale reproductive system
xtestis is covered by three layers (from
outside to inwards):
̞visceral layer of tunica vaginalis:
̎it is lined by flat mesothelial cells.ons of seminiferous tubules lined by spermatogonia, primary and secondary
xThese tight junctions form the blood–testis
barrier.
xThe tight junction divides the intercellular
compartment between the Sertoli cells
into basal and luminal compartment.
xBasal compartment contains spermato
gonia and primary spermatocytes.
xLuminal compartment contains secondary
spermatocytes and spermatids (Fig. 19.5).
Functions of Sertoli Cells
xSertoli cells provide support and nutrition
to spermatogenic cells.
xThe bloodtestis barrier protects the
spermatogenic cells from the harmful
substances (antigens) of blood.
xThey phagocytose the residual bodies.
xSertoli cells secrete androgen-binding
protein (ABP), which concentrates the
testosterone.
xIn fetal testis, Sertoli cells produce anti
mullerian hormone, which inhibits the
development of mullerian duct.
xSertoli cells are nondividing cells, highly
resistant to infection, malnutrition, and
radiation.
xThese produce inhibin, which inhibits the
secretion of follicle-stimulating hormone
(FSH).
Interstitial Cells of Leydig
xThese are large polyhedral cells lying in
the connective tissue between seminif
erous tubules.
xThese are pale staining cells with eccen
tric nucleus and cytoplasm shows unique
needleshaped crystalline inclusion
(Reinke’s crystal).
spermatocytes, spermatids, and sperms are seen.
2.Sertoli cells are seen in between the spermatogenic cells.
3.Interstitial ces of Leydig are seen in between the seminiferous tubules.
xThey secrete testoster
̞tunica albuginea:
̎it is a thin layer of connective tissue
containing collagen, blood vessels,
and lymphatics.
̎along the posterior border, tunica
albuginea is thickened to form medi
astinum testis.
̎septa arising from the mediastinum
testis divide the substance of the
testis into 200 to 300 lobules.
̎each lobule contains one to four
seminiferous tubules.
̎seminiferous tubules contain coiled
part in the front and straight part
behind.
̎straight part enters the medi
astinum testis where it joins and
forms a network called as rete testis.
̎from the upper end of rete testis
12 to 14 efferent ductules arise and
enter the epididymis.
̞tunica vasculosa:
̎highly vascularized connective
tissue which covers the individual
lobule.
microscopic structure
oftestis
seminiferous tubule
xthere are 400 to 600 seminiferous tubules
in each testis.
xeach tubule is surrounded by a basal
lamina supported by connective tissue
which contains muscle-like myoid cells.
xcontraction of myoid cells helps to move
the spermatozoa along the tubule.
xeach seminiferous tubule is lined by
stratified seminiferous epithelium which
contains spermatogenic cells and sertoli
cells(figs. 19.2and19.3).
fig. 19.2diagram of testis (h&e pencil). h&e, hematoxylin and eosin. 3.Interstitia
The pdf contain all the information of various technique ,such as chromatography,spectroscopy,centrifugation,electrophoresis special thanks to Dr.Rambir Singh for helping out the topics easily.Contact for help or suggestion @7985214648 whattapp only
Introduction to microscopy
Different parts of a microscope & their function
Different types of microscopy
Different types of optical microscopy
Different types of electron microscopy
Different terms used in microscopy
Staining- Simple, Differential, Special
Gram Staining
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Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
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Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
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June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Light Microscope and Electron Microscope [Best one]
1.
2.
3.
4. 1- Ocularlense
receive the image from the objective lens, enlarge it and project it
to your eyes
3- Arm
vertical piece supports the head of the microscope, the stage,
the condenser, and focusing controls
2- Objective Lense
receive the image from the specimen slide and enlarges it
three or four lenses are usually located on revolving nosepiece
4- Base
horizontal piece ; supports microscope
5. 5- Stage
platform which supports slide ; hole in center allows light from
condenser to pass through
6- Head
top part of the microscope; contains mirrors which reflect
images to the ocular lenses
7- iLLumination
located above base; includes field diaphragm and adjusting
ring used to control the width of light beam passing through
6. 8- Condenser
series of lenses which focus light on the specimen slide; can be
moved up and down by a knob on the side
9- Diaphragm
controls width of light beam passing through the condenser to the
specimen slide
10- Knobs for moving slides
control fine movement of the slide holder; front-to-back, side-to-
side
12- FineFocus Control11- Course Focus Control
moves the stage up and down to bring image
into final focus; (blue arrow)
moves the stage up and down to bring the image
of the specimen into approximate focus; (black
arrow)
7. Total Magnification
Oil Immersion
Objective Lens
High PowerObjective
Lens
Low Power Objective
Lens
ScanningObjective
Lens
magnification
by 100x
magnification
by 40x
magnification
by 10x
magnification
by 4x
OcularLenses
magnification by 10x normal size
Total Magnification = Magnification of ocular lens x
8. TissuePreparationfor Light Microscope
To make Tissue hard and solid
2-Freezing Technique1- Paraffin Technique
For Lipids and Enzyme histochemistryRoutine and commenest method
1- Sample
Small sample = specimen of tissue .5 cm x .5 cm x .5 cm
2- Fixation
-put in fixative = formalin 10% most commonly used
-prevents putrefaction and autolysis
3- dehydration
-gradual removal of water from tissue to be miscible with paraffin
-put in ascending grades of alchol 70% , 90% , 100% gradually
9. 4- clearance
-put tissue in xylene = xylol which makes it clear
-Xylene is miscible with paraffin and will replace alcohol which is not miscible
with paraffin
5- impregnation
-infiltration of tissues with parrafin in the oven
-put the tissue in soft paraffin then hard paraffin
6- embedding
Put the tissue in hard paraffin to obtain paraffin block
7- sectioning
By rotatory microtome (5-8um thick)
10. 8- Staining
Stain typesClassificationDefinition
1- Acidic stain : Eosin
2- basic stain : Haematoxlin
3- neutral stain : leishman
1- natural of plant origin as
haematoxylin.
2- synthetic as eosin
Dye or substance used
for staining of sections
to differentiate
structures by different
colours
12. WHATISANELECTRONMICROSCOPE?
The electron microscope is a type of microscope that uses a beam
of electrons to create an image of the specimen.
It is capable of much higher magnifications and has a greater
resolving power than a light microscope, allowing it to see much
smaller objects in finer detail.
They are large, expensive pieces of equipment, generally standing
alone in a small, specially designed room and requiring trained
personnel to operate them.
13. HISTORYOFEM
The first electron microscope prototype was built in 1931 by German engineers Ernst
Ruska and Max Knol, capable of magnifying objects by four hundred times, it demonstrated
the principles of an electron microscope
However, two years later, Ruska constructed an electron microscope that exceeded the
resolution of an optical (light) microscope
Manfred von Ardenne pioneered the scanning electron microscope and his universal
electron microscope.
Siemens produced the first commercial TEM in 1939, but the first practical electron
microscope had been built at the University of Toronto in 1938, by Eli Franklin Burton and
students Cecil Hall, James Hillier, and Albert Prebus
16. TRANSMISSIONELECTRONMICROSCOPE(TEM)
The original form of electron microscopy, Transmission electron microscopy (TEM) involves
a high voltage electron beam emitted by an electron gun, usually fitted with
a tungsten filament cathode as the electron source.
The electron beam is accelerated by an anode with respect to the cathode, focused by
electrostatic and electromagnetic lenses, and transmitted through a specimen that is in part
transparent to electrons and in part scatters them out of the beam.
When it emerges from the specimen, the electron beam carries information about the
structure of the specimen that is magnified by the objective lens system of the microscope.
The spatial variation in this information (the "image") is recorded by projecting the
magnified electron image onto a fluorescent viewing screen coated with a phosphor or
scintillator material such as zinc sulfide
17.
18. SCANNING ELECTRON MICROSCOPE
(SEM)
The Scanning Electron Microscope (SEM)produces images by detecting low energy
secondary electrons which are emitted from the surface of the specimen due to
excitation by the primary electron beam.
In the SEM, the electron beam is rastered across the sample, with detectors
building up an image by mapping the detected signals with beam position.
The TEM resolution is about an order of magnitude greater than the SEM
resolution, however, because the SEM image relies on surface processes rather
than transmission it is able to image bulk samples and has a much greater depth of
view, and so can produce images that are a good representation of the 3D structure
of the sample.
19. This is an image of an
ant using an electron
microscope (scanning
microscope )
20. DIFFERENCE BETWEEN
TEM & SEM
TRANSMISSION
E-MICROSCOPE
Higher resolution
Flat (2D) images
Specimen requires
thinning which is tiring
and time consuming
Expensive
Relatively detrimental
for human health
SCANNING
E-MICROSCOPE
Lower resolution
3D images
Simple to prepare
specimens
Cheap
Relatively safe to use
21. SCANNING TRANSMISSION
ELECTRON MICROSCOPE (STEM)
The Scanning Transmission Electron Microscope is very
powerful , and highly versatile instrument , capaple of atomic
resolution imaging and nanoscale analysis.
The high resolution of the TEM is thus possible in STEM. The
focusing action occur before the electrons hit the specimen in
the STEM, but afterward in the TEM.
The ability to scan the e beams allow the user to analyse the
Sample with different techniques such as electron energy loss
spectatory and enery dispresive X-RAY
It is also useful to understand the nature of the material in the
sample
22. REFLECTION ELECTRON
MICROSCOPE (REM)
Reflection Electron Microscope uses an electron beam which is
incident on a surface, but instead of using the transmission
(TEM) or secondary electrons (SEM), the reflected beam of
elastically scattered electrons is detected. This technique is
typically coupled with Reflection High Energy Electron
Diffraction and Reflection high-energy loss spectrum