Methods of Sample Preparation and Assay of Bacterial Biofilms with Special Reference to Their Significance in Agriculture and Extreme Environments

2021 ◽  
pp. 39-65
Author(s):  
Bedaprana Roy ◽  
Debapriya Maitra ◽  
Arup Kumar Mitra
Keyword(s):  
Sample Preparation ◽  
Special Reference ◽  
Extreme Environments ◽  
Bacterial Biofilms

scholarly journals The influence of sample preparation quality on the results of spectral analysis

2020 ◽  
pp. 72-75
Author(s):  
M. V. Lagoyskaya
Keyword(s):  
Spectral Analysis ◽  
Chemical Composition ◽  
Sample Preparation ◽  
Special Reference ◽  
Discharge Chamber ◽  
Small Samples ◽  
Central Laboratory ◽  
Comparative Tests ◽  
Reference Samples ◽  
Spectral Equipment

Сonsiders the possibility of analyzing samples of small diameters without the use of special adapters for determining the chemical composition on spectrometers. Measurements are limited to the size of the hole on the analytical table, which is 12 mm. Accordingly, all analyzed samples must have a diameter of at least 14 mm to completely cover the sample cover of the discharge chamber in order to avoid air entering the chamber. The company manufacturer of spectral equipment offers to use special adapters for the analysis of small samples. But the use of such adapters has a number of drawbacks. These include additional cash costs for the purchase of adapters, the need for additional standardization procedures, the availability of special reference samples. In the laboratory of analytical support (LAS) of the Central Laboratory of the Factory (CLF), all samples of finished rolled products (wire rods or fittings) in size from 5.5 mm to 20 mm are prepared in the form of «blades». The compressed part of the «blade» is the analyzed surface of the sample, which is further processed on a disk grinder and transmitted to the spectral analysis. The article presents the results of comparative tests of valves class U500 between samples in the form of «blades» and in the form of «columns» and concluded that the necessity of use of special adapters.

scholarly journals Recent studies of synthetic antibody-based 3-MCPD determination technology

2021 ◽  
Vol 89 (1) ◽  
Author(s):  
Hasim MUNAWAR ◽  
Prima LUNA ◽  
Irma KRESNAWATY ◽  
Happy WIDIASTUTI
Keyword(s):  
Sample Preparation ◽  
Palm Oil ◽  
Solid Phase ◽  
Empirical Studies ◽  
Extreme Environments ◽  
High Sensitivity ◽  
Maximum Level ◽  
International Agency ◽  
Synthetic Antibody ◽  
Sensitivity And Selectivity

3-Chloro-1,2-propanediol (3-MCPD) is classified by the International Agency for Research on Cancer as carcinogenic material. 3-MCPD will also become one of the European Union's requirements, proposing the maximum level of the 3-MCPD in palm oil until 2.5 ppm. Although the reported technologies GCMS and HPLC-FLD demonstrated high sensitivity and selectivity on 3-MCPD determination, those technologies invest in chemical and time-consuming sample preparation and analysis. Molecularly imprinted polymer (MIP), or a synthetic antibody, can be used to recognize 3-MCPD. MIP is more robust under extreme environments such as temperature and pH. This paper, therefore, aims to discuss the application of MIP on sample extraction and analysis to detect 3-MCPD. MIP is synthesized by polymerization of functional monomers surrounding 3-MCPD as a template. 3-MCPD is then removed from the MIP, leaving active cavities. Thus, these sites can either covalently or non-covalently rebind to 3-MCPD. Computational or empirical studies could investigate the composition of MIP. MIP can be manufactured as MIP-based solid phase extraction (MIPSPE) and MIP-based sensor. Both applications showed significant analytical parameters, such as recovery higher than 90% and detection limit lower than 2.5 ppm.  Therefore, the application of MIP can be flexible for sample preparation and analysis on the 3-MCPD determination. MIP-based technology would be a prospective instrument to detect 3-MCPD.  In the future, producing MIP on an industrial scale will be a challenge to monitor the 3-MCPD level in palm oil.

Pollutant Identification by Selected Area Electron Diffraction

1974 ◽  
Vol 32 ◽  
pp. 532-533
Author(s):  
R. E. Ferrell ◽  
G. G. Paulson ◽  
C. W. Walker
Keyword(s):  
Thermal Treatment ◽  
Electron Diffraction ◽  
Sample Preparation ◽  
Crystal Structures ◽  
Water Samples ◽  
Environmental Samples ◽  
Short Review ◽  
Selected Area Electron Diffraction ◽  
Multiple Component

Selected area electron diffraction (SAD) has been used successfully to determine crystal structures, identify traces of minerals in rocks, and characterize the phases formed during thermal treatment of micron-sized particles. There is an increased interest in the method because it has the potential capability of identifying micron-sized pollutants in air and water samples. This paper is a short review of the theory behind SAD and a discussion of the sample preparation employed for the analysis of multiple component environmental samples.

Preparation of Thin Cadmium Telluride Samples for Electron Microscope Studies

1974 ◽  
Vol 32 ◽  
pp. 548-549
Author(s):  
T. J. Magee ◽  
J. Peng ◽  
J. Bean
Keyword(s):  
Electron Microscope ◽  
Sulfuric Acid ◽  
Solid State ◽  
Sample Preparation ◽  
Cadmium Telluride ◽  
Potassium Dichromate ◽  
Optical Components ◽  
The Past ◽  
Solid State Devices

Cadmium telluride has become increasingly important in a number of technological applications, particularly in the area of laser-optical components and solid state devices, Microstructural characterizations of the material have in the past been somewhat limited because of the lack of suitable sample preparation and thinning techniques. Utilizing a modified jet thinning apparatus and a potassium dichromate-sulfuric acid thinning solution, a procedure has now been developed for obtaining thin contamination-free samples for TEM examination.

A Freeze Shadow Technique for the Preparation of Soft Paint Latexes for Electron Microscopy

1977 ◽  
Vol 35 ◽  
pp. 314-315
Author(s):  
Earl R. Walter ◽  
Glen H. Bryant
Keyword(s):  
Sample Preparation ◽  
High Vacuum ◽  
Vacuum System ◽  
Latex Particles ◽  
New Methods ◽  
Diffusion Pump ◽  
Film Forming ◽  
Routine Basis ◽  
Distribution Studies ◽  
Preparation Techniques

With the development of soft, film forming latexes for use in paints and other coatings applications, it became desirable to develop new methods of sample preparation for latex particle size distribution studies with the electron microscope. Conventional latex sample preparation techniques were inadequate due to the pronounced tendency of these new soft latex particles to distort, flatten and fuse on the substrate when they dried. In order to avoid these complications and obtain electron micrographs of undistorted latex particles of soft resins, a freeze-dry, cold shadowing technique was developed. The method has now been used in our laboratory on a routine basis for several years.The cold shadowing is done in a specially constructed vacuum system, having a conventional mechanical fore pump and oil diffusion pump supplying vacuum. The system incorporates bellows type high vacuum valves to permit a prepump cycle and opening of the shadowing chamber without shutting down the oil diffusion pump. A baffeled sorption trap isolates the shadowing chamber from the pumps.

SEM evaluation of the TEM cold-stage double-film specimen

1984 ◽  
Vol 42 ◽  
pp. 272-273
Author(s):  
Jayesh Bellare
Keyword(s):  
Spatial Distribution ◽  
Sample Preparation ◽  
Sample Thickness ◽  
Specimen Preparation ◽  
Preparation Technique ◽  
Liquid Sample ◽  
Thin Specimen ◽  
Sample Preparation Technique ◽  
Cold Stage ◽  
Film Specimen

Seeing is believing, but only after the sample preparation technique has received a systematic study and a full record is made of the treatment the sample gets.For microstructured liquids and suspensions, fast-freeze thermal fixation and cold-stage microscopy is perhaps the least artifact-laden technique. In the double-film specimen preparation technique, a layer of liquid sample is trapped between 100- and 400-mesh polymer (polyimide, PI) coated grids. Blotting against filter paper drains excess liquid and provides a thin specimen, which is fast-frozen by plunging into liquid nitrogen. This frozen sandwich (Fig. 1) is mounted in a cooling holder and viewed in TEM.Though extremely promising for visualization of liquid microstructures, this double-film technique suffers from a) ireproducibility and nonuniformity of sample thickness, b) low yield of imageable grid squares and c) nonuniform spatial distribution of particulates, which results in fewer being imaged.

Advanced TEM sample preparation techniques for submicron Si devices

1995 ◽  
Vol 53 ◽  
pp. 516-517 ◽  
Author(s):  
P. B. Basham ◽  
H. L. Tsai
Keyword(s):  
Sample Preparation ◽  
Process Development ◽  
Light Transmission ◽  
Specific Area ◽  
Turnaround Time ◽  
Small Hole ◽  
Area Of Interest ◽  
Transmission Electron ◽  
Polished Side ◽  
Preparation Techniques

The use of transmission electron microscopy (TEM) to support process development of advanced microelectronic devices is often challenged by a large amount of samples submitted from wafer fabrication areas and specific-spot analysis. Improving the TEM sample preparation techniques for a fast turnaround time is critical in order to provide a timely support for customers and improve the utilization of TEM. For the specific-area sample preparation, a technique which can be easily prepared with the least amount of effort is preferred. For these reasons, we have developed several techniques which have greatly facilitated the TEM sample preparation.For specific-area analysis, the use of a copper grid with a small hole is found to be very useful. With this small-hole grid technique, TEM sample preparation can be proceeded by well-established conventional methods. The sample is first polished to the area of interest, which is then carefully positioned inside the hole. This polished side is placed against the grid by epoxy Fig. 1 is an optical image of a TEM cross-section after dimpling to light transmission.

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