Field Identification of Soils

Field Identification of Soils Complete classification of soils using the Unified Soil Classification System (USCS) requires lab testing that can take several days. However, engineers often need to rapidly classify soils in the field. Fortunately with a little bit of experience it is possible to quickly classify most soils without the use of any specialized equipment.Two excellent guides to visual classification of soils are ASTM D2488: Standard Practice for Description and Identification of Soils (Visual-Manual Procedure) and the U.S. Army Field Manual 5-410 Military Soils Engineering, (pgs 5–17 through 5–28).This appendix draws heavily from these two references. C.1 EQUIPMENT These tests can be performed using only a water bottle.The following items are helpful in performing visual classification but not necessary. • Pie pan or pizza pan • #4 and #200 sieve. Small 5– diameter sieves are available and are ideal for this purpose. • Pocket penetrometer or Torvane® device. C.2 PROCEDURE C.2.1 Color and Smell 1. Describe the color of the soil. If you have any form of standardized color chart use it.The color should be described when the soil is moist. If the soil is dry, add a bit of water before determining the color. Originally published in Geotechnical Engineering Lab Manual, Kitch (2009). Reprinted here by permission. C-2 Appendix C Field Identification of Soils 2. Describe the wetness of the soil using the moisture classification provided in Table 5.3. 3. If the sample is intact estimate the soil consistency using a pocket penetrometer, if available, or by attempting to push your thumb into the sample. Use the consistency descriptions in Table 5.4. 4. Smell the soil. Classify the smell as (a) None: no odor (b) Earthy: musty or moldy smell (c) Organic: manure or decay (d) Chemical: methane, hydrocarbon, or other chemicals. 5. If the soil has an organic smell, is spongy, and contains large amounts of undecayed plant matter, the soil is peat (Pt). C.2.2 Fine Versus Coarse Grain Determination The objective of this step is to determine whether the soil is coarse grained (gravel and sand) or fine grained (silt and clay).The dividing line between coarse and fine grained particles is the #200 sieve which has an opening size of 0.75 mm. This is also approximately the smallest size that can be seen by the naked eye. 6. Spread a portion of the sample out in a pan or on a plastic sheet. Visually estimate the percent of soil that would pass the #200 sieve (percent that is finer than 0.75 mm). If you have a #200 sieve you may use this to separate the fine and coarse fractions. If you do not have a sieve, assume that any individual particles that you can see with your naked eye are coarse grained. 7. If 50% or more of the soil is coarse grained, then the soil is sand and/or gravel. Proceed to Step C.2.3. 8. If more than 50% is fine grained, then the soil is clay and/or silt. Proceed to Step C.2.4. C.2.3 Coarse Grained Soil Classification 9. Visually determine what percentage of the coarse grained fraction of the soil would be retained on the #4 sieve (percent that is larger than 4.75 mm). If you have a #4 sieve you may use it. If not consider that frozen peas are approximately the size of the openings in a #4 sieve. If 50% or more of the coarse fraction is retained on the #4 sieve, then the soil is gravel. If less than 50% of the coarse fraction is retained on the #4 sieve, then the soil is sand. 10. Determine if the soil is clean or not. Visually determine if less than 10% of the sample passes the #200 sieve. If so, then the soil is a clean sand (SP or SW) or a clean gravel (GP or GW). If 10% or more of the soil passes the number #200 sieve, then the soil is clayey or silty sand or gravel (SC, SM,GC, or GM).You will have to test the fine grained portion of the sample using procedures in section C.2.4 to complete classification of the soil. C.2 Procedure C-3 11. Determine gradation by observing the relative diversity of soil particle sizes. If the soil contains a very large range of particle sizes in a relatively uniform distribution then the soil is well graded as is either SW or GW. If not it is poorly graded and is either SP or GP. Most soils are poorly graded.When in doubt assume it is poorly graded. 12. Examine a number of individual particles for their shape. Describe the particle shape using the Figure 4.15. 13. If your soil is a clean sand or gravel, classification is complete and there is no need to perform the tests in section C.2.4. If not, proceed. C.2.4 Fine Grained Soil Classification: Distinguishing Silts from Clays Silts and clays are distinguished primarily based on their relative plasticity and dry strength. Clays have a greater ability to absorb water and remain in a plastic state than do silts. Clays also tend to have a higher strength when dried than do slits. 14. Separate out a small handful of soil finer than the #40 sieve.The opening in a #40 sieve is approximately the size of table salt or fine beach sand. Dry Strength Test 15. Mold a sample of the soil into a 1– diameter ball adding water if necessary. Flatten the ball into a disk about thick. 16. Set the disk aside to dry. You may put the disk on a warm surface such as the hood of a car to speed drying. 17. When the disk is completely dry, test its drying strength by breaking the disk between your fingers. Use the dry strength description in Table C.1 to describe its strength. Dilatancy or Wet Shaking Test 18. Select enough soil to form a ball approximately in diameter. Form the soil into a ball adding enough water that the soil is soft but does not have free water on the surface. 12– 12– TABLE C.1 Dry Strength Test Classificationa Strength Classification Behavior of Dry Specimen None Crumbles into powder with slightest finger pressure Low Crumbles into powder with moderate finger pressure Medium Breaks into pieces with considerable finger pressure High Cannot be broken into pieces with finger pressure, but can be broken using thumb and forefinger against a hard surface Very high Cannot be broken using thumb and forefinger against a hard surface aBased on ASTM 2488 and FM 5-410. C-4 Appendix C Field Identification of Soils TABLE C.2 Dilatancy Test Classificationa Classification Behavior of Specimen During Test None No sheen forms on surface of pat during shaking Slow Sheen appears slowly on pat during shaking and does not disappear or disappears slowly when flexing hand after shaking Fast Sheen appears quickly on pat during shaking and disappears quickly when flexing hand after shaking aBased on ASTM 2488 and FM 5-410. TABLE C.3 Plasticity Classification Using Ribbon Testa Plasticity Behavior of Specimen During Test Nonplastic No ribbon can be formed Low Ribbon can be formed with difficulty but will hold together lengths of only 3– or less Medium Ribbon can be formed and will hold together for lengths of 3– to 6– High Ribbon can be formed and will hold together for a length of 6– or more aBased on FM 5-410. 19. Flatten the ball of soil out to form a pat in the palm of your right hand.With your right palm facing up, slap your right hand down into your left hand several times. Slap vigorously. 20. Observe the surface of the soil pat to see if water appears.The water will be seen as a sheen on surface of the pat. Note how quickly the sheen forms if at all. 21. If a sheen does form flex the hand holding the soil pat open and slightly closed. Observe if the sheen goes away and, if so, how quickly. 22. Classify the reaction to the dilatancy test as, none, slow, or rapid based on the descriptions in Table C.2. Ribbon Test 23. Select enough soil to make a cylinder of soil to in diameter and 3 to 4– long. Mold the soil with enough water that it is plastic but not sticky. 24. Carefully squeeze the soil between your thumb and forefinger to form a ribbon to thick. Let the ribbon dangle below your hand as you form it. Try to make the ribbon as long as possible without it breaking. Note the length of the ribbon at the time it breaks. Describe the plasticity of the soil as nonplastic, low, medium, or high based on the descriptions in Table C.3. Determination of Fine Grained Soil Type 25. Using the results of the dry strength, dilatancy, and ribbon tests determine the soil classification using Table C.4. 1 14– 8– 1 34– 2– C.2 Procedure C-5 TABLE C.4 Classification of Fine Soil Based on Dry Strength, Dilatancy, and Plasticitya USCS Group Symbol Dry Strength Dilatancy Plasticity ML None to low Slow to rapid Nonplastic to low CL Medium to high None to slow Medium MH Low to medium None to slow Low to medium CH High to very high None High aBased on ASTM 2488 and FM 5-410. C.2.5 Completing Classification Follow the flow sheet in Figure C.1 to determine the USCS group symbol for the soil. To verify the classification you must perform a complete lab analysis and classify soil according to ASTM D2487: Classification of Soils for Engineering Purposes (Unified Soil Classification System). Yes Estimate % passing #200 sieve Perform dry strength, dilatancy, and ribbon tests on fine-grained portion of sample Estimate % passing #4 sieve > 10% passing #200 sieve? > 10% passing #200 sieve? Estimate gradation Test fine-grained portion Estimate gradation Test fine-grained portion 17.research on optical microscopy Hello, can you please write a brief introduction about Optical microscopy, Electron Microscopy, XRD and XRF. Then a brief description of each under its own section. 1)Just follow the red sentences. 2)There is no words limit, just write appropriate description of each microscope and include pictures of the microscope structures when you explain their components. Don't forget, a brief introduction and conclusion about the microscopes indicated. Use scientific sources better, as much as you can. Please note. a brief description doesn't mean just 100 words! No less than 200 at least! And please ask me any question you want to know. Report Structure – Suggestion Only Title: Characterisation of a mineral assemblage using Optical, SEM, EDS XRD, XRF techniques 1.0 Introduction The purpose of this investigation is to characterise a mineral assemblage using the following techniques: Optical Microscopy Electron Microscopy X-ray Powder diffraction X-ray Fluorescence Spectroscopy etc etc ……. 2.0 Optical Characterisation of Rock •    Brief description of microscope – type, digital image capture characteristics •    Optical photography of whole rock •    Identification of the number of phases accompanied by optical photography of each phase. •    Image analysis of mineral size – if possible or applicable •    Speculation as to the rock type – if possible. 3.0 Electron Microscopy Characterisation of Individual Mineral Phases •    Introduction to scanning electron microscopy •    How does an SEM work? •    What information can you obtain from an SEM – images and chemical information? •    SEM images of individual phases. Identification of characteristic features  such    as pronounced cleavage of crystallographic form. •    Comparison with corresponding optical images. •    Discuss issues such as: •    Resolution •    Depth of field •    Do the SEM images contribute constructively to characterising the mineral phases. •    (If possible or applicable) Chemical Analysis using the SEM: Energy dispersive X-ray Spectroscopy  (EDS) •    Brief description of the operational principles of EDS •    Acquire EDS spectra from each of the mineral phases. 4.0    Chemical Analysis of Individual Phases using X-ray Fluorescence    Spectroscopy (XRF) •    Brief description of the operational principles of XRF •    Comparison of the complementary techniques of EDS and XRF •    Acquire 2? XRF scans to characterize instrument response •    Acquire 2? XRF scans from each mineral phase and the whole rock – see following table of experimental tasks •    Compare elemental information obtained from XRF with that obtained using    EDS (if possible or applicable) 5.0    Crystal Structure Characterisation of Individual Mineral Phases using    Powder X-ray Diffraction (XRD) •    Brief description of the operational principles of XRD •    Scans from appropriate material to demonstrate the instrument response from amorphous/crystalline/polycrystalline/single crystal material ( see following table for suggestions. •    Acquire 2? XRD scans from each mineral phase and the whole rock– see following table of experimental data. •    Use the XRD data along with SEM and XRF to identify individual phases. 6.0    Conclusion Optical Microscopy, Electron Microscopy, XRD and X Optical Microscopy, Electron Microscopy, XRD and XRF Introduction There are numerous instrumental methods that are used in the analysis of geological materials, trace elements, and molecular structures of specimens. The decision on the type of method or instrument to use depends on the specific type of material being analyzed. There have also been numerous developments in the instrumental methods which have resulted to more powerful and precise instruments. Description 1.    Optical Microscopy An optical microscope is a type of microscope that uses light & lenses to magnify a sample. The focused light is sent through a path and forms a tight beam which is then made to pass through the sample to create an image. The image then passes through one or a series of lenses thus magnifying the sample until it reaches eye of the observer or the camera. The observer is able to see the light rays directly. There are different types of optical microscopes. These include: simple light microscope – it uses one lens to magnify a specimen and therefore it does not attain high magnification/resolution; compound light microscope – it uses 2 sets of lenses (eyepiece and objective lens) to generate images; monocular microscope – it has one eyepiece; and binocular microscope – it has two eyepieces which minimize eye strain. Optical microscopes have two basic functions: to illuminate specimens and to create magnified images of specimens. These microscopes obtain clear and sharp images; they can change magnification; and bring the images into focus to be best viewed by the observer. 2.    Electron Microscopy An electron microscope is a form of microscope that uses electrons to produce a magnified image of a specimen. Electron microscopes have high resolution power and magnifications that light microscopes. There are two types of electron microscopes: transmission electron microscope (TEM) and scanning electron microscope (SEM). A SEM creates images by sensing secondary electrons that are emitted from the surface of the specimen as a result of being excited by the primary electrons. SEM images rely on interactions of electrons on the surface of the sample and therefore the microscope can image many specimens and it also has a greater depth of view. Therefore a SEM can produce 3D images. Specimens to be viewed using an electron microscope are required to be prepared. Some of the techniques used to prepare the specimens include: fixation, dehydration, embedding, sectioning, staining, cryofixation, sputter coating, etc. 3.    XRD (X-ray Powder Diffraction) XRD is an analytical method that is applied in phase identification of crystalline materials. The operation of XRD is based on its fundamental principles which are as follows: the basis of XRD is on monochromatic X-rays’ constructive interference and crystalline specimens. There is a cathode ray tube which produces the x-rays which are filtered to generate monochromatic radiation then concentrated through collimation before being directed towards the specimen. Constructive interference is produced through interaction of incident rays. The diffracted x-rays are detected, processed then counted. 4.    XRF (X-ray Fluorescent Spectroscopy) XRF is a technique used for examining material samples and measuring coating thickness. The fundamental principle of XRF is that primary x-radiation excites the sample causing electrons in the inner surfaces to be knocked. The electrons from the outer shells then fill the consequential voids releasing a fluorescence radiation that is analyzed using a detector. The operation of XRF method is similar to that of EDS because they use the same fundamental principles. Conclusion Microscopes are largely used in understanding the molecular structures of several specimens. These instruments are very essential in today’s applications and are used in almost all industries including healthcare, nanotechnology, mining, manufacturing, etc. The instruments have largely improved precision of product manufacture and processing. It is now easier to analyze even the smallest material samples Optical Microscopy, Electron Microscopy, XRD and XRF Introduction There are numerous instrumental methods that are used in the analysis of geological materials, trace elements, and molecular structures of specimens. The decision on the type of method or instrument to use depends on the specific type of material being analyzed. There have also been numerous developments in the instrumental methods which have resulted to more powerful and precise instruments. Description 1.    Optical Microscopy An optical microscope is a type of microscope that uses light & lenses to magnify a sample. The focused light is sent through a path and forms a tight beam which is then made to pass through the sample to create an image. The image then passes through one or a series of lenses thus magnifying the sample until it reaches eye of the observer or the camera. The observer is able to see the light rays directly. There are different types of optical microscopes. These include: simple light microscope – it uses one lens to magnify a specimen and therefore it does not attain high magnification/resolution; compound light microscope – it uses 2 sets of lenses (eyepiece and objective lens) to generate images; monocular microscope – it has one eyepiece; and binocular microscope – it has two eyepieces which minimize eye strain. Optical microscopes have two basic functions: to illuminate specimens and to create magnified images of specimens. These microscopes obtain clear and sharp images; they can change magnification; and bring the images into focus to be best viewed by the observer. 2.    Electron Microscopy An electron microscope is a form of microscope that uses electrons to produce a magnified image of a specimen. Electron microscopes have high resolution power and magnifications that light microscopes. There are two types of electron microscopes: transmission electron microscope (TEM) and scanning electron microscope (SEM). A SEM creates images by sensing secondary electrons that are emitted from the surface of the specimen as a result of being excited by the primary electrons. SEM images rely on interactions of electrons on the surface of the sample and therefore the microscope can image many specimens and it also has a greater depth of view. Therefore a SEM can produce 3D images. Specimens to be viewed using an electron microscope are required to be prepared. Some of the techniques used to prepare the specimens include: fixation, dehydration, embedding, sectioning, staining, cryofixation, sputter coating, etc. 3.    XRD (X-ray Powder Diffraction) XRD is an analytical method that is applied in phase identification of crystalline materials. The operation of XRD is based on its fundamental principles which are as follows: the basis of XRD is on monochromatic X-rays’ constructive interference and crystalline specimens. There is a cathode ray tube which produces the x-rays which are filtered to generate monochromatic radiation then concentrated through collimation before being directed towards the specimen. Constructive interference is produced through interaction of incident rays. The diffracted x-rays are detected, processed then counted. 4.    XRF (X-ray Fluorescent Spectroscopy) XRF is a technique used for examining material samples and measuring coating thickness. The fundamental principle of XRF is that primary x-radiation excites the sample causing electrons in the inner surfaces to be knocked. The electrons from the outer shells then fill the consequential voids releasing a fluorescence radiation that is analyzed using a detector. The operation of XRF method is similar to that of EDS because they use the same fundamental principles. Conclusion Microscopes are largely used in understanding the molecular structures of several specimens. These instruments are very essential in today’s applications and are used in almost all industries including healthcare, nanotechnology, mining, manufacturing, etc. The instruments have largely improved precision of product manufacture and processing. It is now easier to analyze even the smallest material samples References Alejandro G. Marangoni and M. Fernanda Peyronel. (March 31, 2014). X-Ray Powder Diffractometry. Retrieved from http://lipidlibrary.aocs.org/Biochemistry/content.cfm?ItemNumber=40299 Cassandra Marnocha. (n.d.). Light Microscope: Definition, Uses & Parts. Retrieved from http://study.com/academy/lesson/light-microscope-definition-uses-parts.html Chris Woodford. (April 1, 2015). Electron Microscopes. Retrieved from http://www.explainthatstuff.com/electronmicroscopes.html Helmut Fischer. (n.d.). X-Ray Fluorescence Measuring Systems. Retrieved from http://xrf-spectroscopy.com/ IvyRose Holistic. (2014). What is an Electron Microscope? Retrieved from http://www.ivyroses.com/Biology/Techniques/What-is-an-Electron-Microscope.php James M. Githrie. (August 2012). Overview of X-ray Fluorescence. Retrieved from http://archaeometry.missouri.edu/xrf_overview.html John Innes Centre. (n.d.). Microscopy. Retrieved from https://www.jic.ac.uk/microscopy/intro_EM.html Olympus. (n,d,). Optical Microscopes. Retrieved from http://www.olympus-ims.com/en/microscope/terms/feature10/ Science Education Resource Center. (June 20, 2015). X-ray Powder Diffraction (XRD). Retrieved from http://serc.carleton.edu/research_education/geochemsheets/techniques/XRD.html Thermo Applied Research Laboratories. (1999). Introduction to Powder/Polycrystalline Diffraction: Basics of X-Ray Diffraction. Thermo ARL: SA. Optical Microscopy, Electron Microscopy, XRD and XRF Name Course Professor Date Optical Microscopy, Electron Microscopy, XRD and XRF Introduction There are numerous instrumental methods that are used in the analysis of geological materials, trace elements, and molecular structures of specimens. The decision on the type of method or instrument to use depends on the specific type of material being analyzed. There have also been numerous developments in the instrumental methods which have resulted to more powerful and precise instruments. Description 1.    Optical Microscopy An optical microscope is a type of microscope that uses light & lenses to magnify a sample. The focused light is sent through a path and forms a tight beam which is then made to pass through the sample to create an image. The image then passes through one or a series of lenses thus magnifying the sample until it reaches eye of the observer or the camera. The observer is able to see the light rays directly. There are different types of optical microscopes. These include: simple light microscope – it uses one lens to magnify a specimen and therefore it does not attain high magnification/resolution; compound light microscope – it uses 2 sets of lenses (eyepiece and objective lens) to generate images; monocular microscope – it has one eyepiece; and binocular microscope – it has two eyepieces which minimize eye strain. Optical microscopes have two basic functions: to illuminate specimens and to create magnified images of specimens. These microscopes obtain clear and sharp images; they can change magnification; and bring the images into focus to be best viewed by the observer. 2.    Electron Microscopy An electron microscope is a form of microscope that uses electrons to produce a magnified image of a specimen. Electron microscopes have high resolution power and magnifications that light microscopes. There are two types of electron microscopes: transmission electron microscope (TEM) and scanning electron microscope (SEM). A SEM creates images by sensing secondary electrons that are emitted from the surface of the specimen as a result of being excited by the primary electrons. SEM images rely on interactions of electrons on the surface of the sample and therefore the microscope can image many specimens and it also has a greater depth of view. Therefore a SEM can produce 3D images. Specimens to be viewed using an electron microscope are required to be prepared. Some of the techniques used to prepare the specimens include: fixation, dehydration, embedding, sectioning, staining, cryofixation, sputter coating, etc. 3.    XRD (X-ray Powder Diffraction) XRD is an analytical method that is applied in phase identification of crystalline materials. The operation of XRD is based on its fundamental principles which are as follows: the basis of XRD is on monochromatic X-rays’ constructive interference and crystalline specimens. There is a cathode ray tube which produces the x-rays which are filtered to generate monochromatic radiation then concentrated through collimation before being directed towards the specimen. Constructive interference is produced through interaction of incident rays. The diffracted x-rays are detected, processed then counted. 4.    XRF (X-ray Fluorescent Spectroscopy) XRF is a technique used for examining material samples and measuring coating thickness. The fundamental principle of XRF is that primary x-radiation excites the sample causing electrons in the inner surfaces to be knocked. The electrons from the outer shells then fill the consequential voids releasing a fluorescence radiation that is analyzed using a detector. The operation of XRF method is similar to that of EDS because they use the same fundamental principles. Conclusion Microscopes are largely used in understanding the molecular structures of several specimens. These instruments are very essential in today’s applications and are used in almost all industries including healthcare, nanotechnology, mining, manufacturing, etc. The instruments have largely improved precision of product manufacture and processing. It is now easier to analyze even the smallest material samples References Alejandro G. Marangoni and M. Fernanda Peyronel. (March 31, 2014). X-Ray Powder Diffractometry. Retrieved from http://lipidlibrary.aocs.org/Biochemistry/content.cfm?ItemNumber=40299 Cassandra Marnocha. (n.d.). Light Microscope: Definition, Uses & Parts. Retrieved from http://study.com/academy/lesson/light-microscope-definition-uses-parts.html Chris Woodford. (April 1, 2015). Electron Microscopes. Retrieved from http://www.explainthatstuff.com/electronmicroscopes.html Helmut Fischer. (n.d.). X-Ray Fluorescence Measuring Systems. Retrieved from http://xrf-spectroscopy.com/ IvyRose Holistic. (2014). What is an Electron Microscope? Retrieved from http://www.ivyroses.com/Biology/Techniques/What-is-an-Electron-Microscope.php James M. Githrie. (August 2012). Overview of X-ray Fluorescence. Retrieved from http://archaeometry.missouri.edu/xrf_overview.html John Innes Centre. (n.d.). Microscopy. Retrieved from https://www.jic.ac.uk/microscopy/intro_EM.html Olympus. (n,d,). Optical Microscopes. Retrieved from http://www.olympus-ims.com/en/microscope/terms/feature10/ Science Education Resource Center. (June 20, 2015). X-ray Powder Diffraction (XRD). Retrieved from http://serc.carleton.edu/research_education/geochemsheets/techniques/XRD.html Thermo Applied Research Laboratories. (1999). Introduction to Powder/Polycrystalline Diffraction: Basics of X-Ray Diffraction. Thermo ARL: SA. Optical Microscopy, Electron Microscopy, XRD and XRF Name Course Professor Date Optical Microscopy, Electron Microscopy, XRD and XRF Introduction There are numerous instrumental methods that are used in the analysis of geological materials, trace elements, and molecular structures of specimens. The decision on the type of method or instrument to use depends on the specific type of material being analyzed. There have also been numerous developments in the instrumental methods which have resulted to more powerful and precise instruments. Description 1.    Optical Microscopy An optical microscope is a type of microscope that uses light & lenses to magnify a sample. The focused light is sent through a path and forms a tight beam which is then made to pass through the sample to create an image. The image then passes through one or a series of lenses thus magnifying the sample until it reaches eye of the observer or the camera. The observer is able to see the light rays directly. There are different types of optical microscopes. These include: simple light microscope – it uses one lens to magnify a specimen and therefore it does not attain high magnification/resolution; compound light microscope – it uses 2 sets of lenses (eyepiece and objective lens) to generate images; monocular microscope – it has one eyepiece; and binocular microscope – it has two eyepieces which minimize eye strain. Optical microscopes have two basic functions: to illuminate specimens and to create magnified images of specimens. These microscopes obtain clear and sharp images; they can change magnification; and bring the images into focus to be best viewed by the observer. Figure 1 [MicroscopyU: https://www.microscopyu.com/articles/digitalimaging/digitalintro.html] 2.    Electron Microscopy An electron microscope is a form of microscope that uses electrons to produce a magnified image of a specimen. Electron microscopes have high resolution power and magnifications that light microscopes. There are two types of electron microscopes: transmission electron microscope (TEM) and scanning electron microscope (SEM). A SEM creates images by sensing secondary electrons that are emitted from the surface of the specimen as a result of being excited by the primary electrons. SEM images rely on interactions of electrons on the surface of the sample and therefore the microscope can image many specimens and it also has a greater depth of view. Therefore a SEM can produce 3D images. Specimens to be viewed using an electron microscope are required to be prepared. Some of the techniques used to prepare the specimens include: fixation, dehydration, embedding, sectioning, staining, cryofixation, sputter coating, etc. Figure 2: [Wikipedia] When a specimen target interacts with an electron beam, numerous emissions are produced including x-rays. The x-rays of several elements are separated by an energy dispersive x-ray spectroscopy (EDS) detector. EDS system software is used to scrutinize the energy spectrum so as to get large quantities of the specific elements. EDS detectors contain crystals that absorb energy of the incoming x-rays through ionization. The crystals yield free electrons then they become conductive this generating electrical charge bias. The energy of the individual x-rays is then converted into electrical voltage which relates to the element’s characteristic x-ray. 3.    XRD (X-ray Powder Diffraction) XRD is an analytical method that is applied in phase identification of crystalline materials. The operation of XRD is based on its fundamental principles which are as follows: the basis of XRD is on monochromatic X-rays’ constructive interference and crystalline specimens. There is a cathode ray tube which produces the x-rays which are filtered to generate monochromatic radiation then concentrated through collimation before being directed towards the specimen. Constructive interference is produced through interaction of incident rays. The diffracted x-rays are detected, processed then counted. Figure 3: [1] 4.    XRF (X-ray Fluorescent Spectroscopy) XRF is a technique used for examining material samples and measuring coating thickness. The fundamental principle of XRF is that primary x-radiation excites the sample causing electrons in the inner surfaces to be knocked. The electrons from the outer shells then fill the consequential voids releasing a fluorescence radiation that is analyzed using a detector. The operation of XRF method is similar to that of EDS because they use the same fundamental principles. Figure 4: [8] Conclusion Microscopes are largely used in understanding the molecular structures of several specimens. These instruments are very essential in today’s applications and are used in almost all industries including healthcare, nanotechnology, mining, manufacturing, etc. The instruments have largely improved precision of product manufacture and processing. It is now easier to analyze even the smallest material samples References [1] Alejandro G. Marangoni and M. Fernanda Peyronel. (March 31, 2014). X-Ray Powder Diffractometry. Retrieved from http://lipidlibrary.aocs.org/Biochemistry/content.cfm?ItemNumber=40299 [2] Cassandra Marnocha. (n.d.). Light Microscope: Definition, Uses & Parts. Retrieved from http://study.com/academy/lesson/light-microscope-definition-uses-parts.html [3] Chris Woodford. (April 1, 2015). Electron Microscopes. Retrieved from http://www.explainthatstuff.com/electronmicroscopes.html [4] Helmut Fischer. (n.d.). X-Ray Fluorescence Measuring Systems. Retrieved from http://xrf-spectroscopy.com/ [5] IvyRose Holistic. (2014). What is an Electron Microscope? Retrieved from http://www.ivyroses.com/Biology/Techniques/What-is-an-Electron-Microscope.php [6] James M. Githrie. (August 2012). Overview of X-ray Fluorescence. Retrieved from http://archaeometry.missouri.edu/xrf_overview.html [7] John Innes Centre. (n.d.). Microscopy. Retrieved from https://www.jic.ac.uk/microscopy/intro_EM.html [8] Projects Exeter. X-Ray fluorescence spectrometry (XRF). Retrieved from https://projects.exeter.ac.uk/geomincentre/estuary/Main/xrf.htm [9] Olympus. (n.d,). Optical Microscopes. Retrieved from http://www.olympus-ims.com/en/microscope/terms/feature10/ [10] Science Education Resource Center. (June 20, 2015). X-ray Powder Diffraction (XRD). Retrieved from http://serc.carleton.edu/research_education/geochemsheets/techniques/XRD.html [11] Thermo Applied Research Laboratories. (1999). Introduction to Powder/Polycrystalline Diffraction: Basics of X-Ray Diffraction. Thermo ARL: SA.