standard sample
Recently Published Documents


TOTAL DOCUMENTS

279
(FIVE YEARS 74)

H-INDEX

19
(FIVE YEARS 3)

2021 ◽  
Vol 10 (4) ◽  
pp. 115-121
Author(s):  
E. V. Kuvaeva ◽  
D. A. Kolesnik ◽  
P. O. Levshukova ◽  
I. I. Terninko ◽  
I. P. Yakovlev ◽  
...  

Introduction. The standard samples (SS) use is a necessary condition for the medicines' quality control implementation. Their development is an urgent problem for the pharmaceutical industry, especially for new biologically active compounds that can be further used as pharmaceuticals.Aim. This work aim is to establish the 5-butyl-1,2-diphenyl-6-oxo-1,6-dihydro pyrimidone-4-olate sodium quantitative content, for which anti-inflammatory and analgesic activity was previously proven, in a standard sample.Materials and methods. This work aim is to establish the 5-butyl-1,2-diphenyl-6-oxo-1,6-dihydro pyrimidone-4-olate sodium quantitative content, for which anti-inflammatory and analgesic activity was previously proven, in a standard sample. The main method for establishing a substance quantitative content in the SS is the material balance method. The water determination was carried out according to K. Fisher's method (semimicro method). Sulphated ash was determined according to the XIV edition Russian Federation State Pharmacopoeia General Pharmacopoeia Monograph "Sulphated ash". Related impurities and their content were assessed using the HPLC method on a Flexar liquid chromatograph equipped with a diode array detector (Perkin Elmer, USA). The residual solvents' determination was carried out by the headspace method using a gas chromatograph GC-2010Plus Shimadzu with a flame ionization detector. As an additional method for establishing the main component quantitative content, acidimetric titration with the equivalence point potentiometric indication was carried out.Results and discussion. The percentage was determined for the following indicators: water, residual organic solvents, related impurities, sulphated ash. Using the material balance method, it was found that the 5-butyl-1,2-diphenyl-6-oxo-1,6-dihydropyrimidin-4-olate sodium percentage in a standard sample is 96.01 ± 0.50 %. It was found by acidimetric titration that the 5-butyl-1,2-diphenyl-6-oxo 1,6-dihydropyrimidin- 4-olate sodium quantitative content in SS is 95.12 ± 0.02 %. The difference in the certified value can be explained by the fact that during titration, the SS aciform is released, which precipitates in an aqueous medium and contributes to a shift in the equilibrium and pH value. Consequently, the equivalence point is reached somewhat earlier. However, the data are practically comparable, but it is necessary to use the value obtained by the material balance method.Conclusion. A standard sample certification parameters were determined: water content, residual organic solvents, sulphated ash, related impurities. The main component quantitative content was determined using the material balance method and titrimetry (acidimetry with the equivalence point potentiometric indication).


2021 ◽  
Vol 87 (12) ◽  
pp. 63-72
Author(s):  
S. A. Smirnova ◽  
I. B. Afanasyev ◽  
G. I. Bebeshko ◽  
G. G. Omel’yanyuk

We present and discuss the results of the validation of a forensic qualitative testing technique which consists in the detection of condensed traces of the gunshot residue (GSR) in the form of individual microparticles on the objects under study and their identification by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) using a scanning electron microscope Mira III (Tescan, Czech Republic) equipped with a system of X-ray microanalysis INCA GSR 450 (Oxford Nanoanalysis, Great Britain). The procedure for detecting GSR particles containing heavy metal compounds, systems of their classification and interpretation of test results are described. The suitability of the methodology for solving forensic problems has been confirmed. The validation procedure consists in assessing the reliability by comparing the test results obtained by experts (A and B) in two laboratories at different times using the same device, and in confirming the competence of experts proceeding from the results of blind tests. A standard sample ENFSI GSR PT 2018 A-03-07 is used. Each of the experts determined the number of particles classified as GSR present in control samples taken in a ballistic laboratory during a full-scale experiment: from the hands of the shooter; from the hands of a person who did not shoot; without microparticles (clean stage of an electron microscope). The reliability of the technique is characterized by the index (probability) of correct results of detecting GSR particles in the standard sample of at least 95.8% and by a small proportion of false results (no more than 5.4%). The competence of the experts is proved by the consistent results of «blind» testing of control full-scale samples, containing and not containing GSR particles obtained in different laboratories. The results of the validation indicate the suitability of the method for obtaining reliable and valid information about the presence of GSR particles on the objects under study.


Author(s):  
Alexander Tucci ◽  
Elena Plante ◽  
John J. Heilmann ◽  
Jon F. Miller

Purpose: This exploratory study sought to establish the psychometric stability of a dynamic norming system using the Systematic Analysis of Language Transcripts (SALT) databases. Dynamic norming is the process by which clinicians select a subset of the normative database sample matched to their individual client's demographic characteristics. Method: The English Conversation and Student-Selected Story (SSS) Narrative databases from SALT were used to conduct the analyses in two phases. Phase 1 was an exploratory examination of the standard error of measure (SEM) of six clinically relevant transcript metrics at predetermined sampling intervals to determine (a) whether the dynamic norming process resulted in samples with adequate stability and (b) the minimum sample size required for stable results. Phase 2 was confirmatory, as random samples were taken from the SALT databases to simulate clinical comparison samples. These samples were examined (a) for stability of SEM estimations and (b) to confirm the sample size findings from Phase 1. Results: Results of Phase 1 indicated that the SEMs for the six transcript metrics across both databases were low relative to each metric's scale. Samples as small as 40–50 children in the Conversation database and 20–30 children in the SSS Narrative database resulted in stable SEM estimations. Phase 2 confirmed these findings, indicating that age bands as small as ±4 months from a given center-point resulted in stable estimations provided there were approximately 35 children or more in the comparison sample. Conclusion: Psychometrically stable comparison samples can be achieved using SALT's dynamic norming system that are much smaller than the standard sample size recommended in most tests of children's language.


2021 ◽  
Vol 6 (2(62)) ◽  
pp. 47-52
Author(s):  
Igor Nevliudov ◽  
Dmytro Yanushkevych ◽  
Leonid Ivanov

The object of research is robotic military complexes used in the system of humanitarian demining. This work aims to study the requirements for robotic military complexes (including manipulators that are sucked into them) and to develop proposals for their use in humanitarian demining. The research is based on the application of a functional approach to the construction of models for the formation of requirements for robotic military complexes (RMC), which are sucked into the system of humanitarian demining. It is established that the creation of RMC requires a significant study of the core of the most important technologies that are needed to create the entire range of promising RMC. Thus the standard sample RMC can be presented in the form of set of functionally connected elements: the basic carrier, the mobile platform, the specialized hinged/built-in equipment in the form of a set of removable modules of useful (target) purpose, means of maintenance and service used at preparation for application and technical operation robot. The composition of specialized equipment is set based on the functional purpose of the RMC. The classification of RMC is given, which provides for their division into three categories: the first generation – controlled devices, the second generation – semi-autonomous devices and the third generation – autonomous devices. The analysis of modern RMC which are developed in Ukraine and the advanced countries of the world and the analysis of structure of components of system of humanitarian demining is carried out. It is established that the organization of the humanitarian demining system with the use of RMC should include of explosive objects (EO) reconnaissance, search, marking, their identification and direct demining. Unmasking signs of EO, as well as modern methods and detectors of EO detection are considered. One of the new promising methods of mine detection is parametric. However, in real application, the most promising is the use of a combination of electromagnetic, optical and mechanical methods. The application of the proposed approaches will increase the efficiency of humanitarian demining and reduce human losses in its implementation.


2021 ◽  
Vol 11 (22) ◽  
pp. 10728
Author(s):  
Zuzana Szabová ◽  
Richard Kuracina ◽  
Martin Sahul ◽  
Miroslav Mynarz ◽  
Petr Lepík ◽  
...  

A commercially available pyrotechnic igniter was used according to the EN 14034 and ASTM E1226a Standards to study the explosiveness of dispersed dusts. Its pyrotechnic composition consists of 1.2 g of zirconium (40% wt.), barium peroxide (30% wt.) and barium nitrate (30% wt.). The energy released during the combustion of that amount of composition is 5 kJ. The article investigates the influence of aging of the pyrotechnic composition in the igniter on its initiation parameters. In the study, igniters of different years from date of manufacture were used: Igniter 1, manufactured in 2021 (less than 1 year from date of manufacture), and Igniter 2 (more than 2 years from date of manufacture). The study was performed in the KV 150M2 explosion chamber with a volume of 365 L and the 20 L sphere chamber with a volume of 20 L. A standard sample of Lycopodium clavatum was used in the KV 150M2 explosion chamber. Magnesium and benzoic acid were used as the samples in the 20 L sphere explosion chamber. The experiment showed that the explosion pressure Pmax of the igniter with more than 2 years from date of manufacture decreased by up to 10%, while the value of the explosion constant Kst decreased by up to 40%. The attained results proved that aging of igniters affects their explosion parameters and measurement accuracy.


2021 ◽  
Vol 2094 (5) ◽  
pp. 052011
Author(s):  
Sh M Masharipov ◽  
K R Ruzmatov ◽  
S A Rahmatullayev ◽  
F F Fattoyev ◽  
M M Mahmudjonov ◽  
...  

Abstract The article assessed and investigated the uncertainty of measurements of standard samples of substances and materials in physicochemical measurements based on standard test methods. A general approach to estimating the sources of uncertainty of standard samples is described. Uncertainties from heterogeneity of standard sample material. uncertainty from instability of standard sample characteristic values. uncertainty from method of setting reference value are investigated. Purity of substances is the main parameter that needs to be paid attention to when studying their properties. This is all the more important when it comes to using a pure substance as some approximation to the prototype reference value. since only this unit of seven main units in the International System of Units (SI system) does not have its own standard. In this sense. an important scientific task is the comprehensive study of pure substances for their practical use as benchmarks for comparison in metrological works and analytical research. The main and very important part of the measurement traceability system are materials with certified (certified) content of components and defined uncertainties of these values (standard samples of the approved type). which require pure substances certified at a higher - reference level. i.e. comparison standards.


2021 ◽  
Vol 877 (1) ◽  
pp. 012007
Author(s):  
M D M Ali ◽  
M Husseini ◽  
N A Khudhair

Abstract In this research, the environmental reality of the ditches to rainwater drain located in the residential neighborhoods of Al-Hilla city in Iraq was studied. The study was conducted on three ditches near schools and health center within three residential neighborhoods. Chemical laboratory tests (BOD, COD, TSS, TN, TP, NO2-, NO3-, SO42-, Cl-, CN-, pH, T, DO) were proceeded on this water and it was found that the water is high polluted in sewage water compared to the sewage entering the treatment plant in the city and comparing with samples of water taken from ditches outside the city (as a standard sample). The pollution of this ditches with sewage water is considerable hazard on people health in this urban area, especially on children, students and the people come in to the health center in this areas.


Author(s):  
Casper Sahl Poulsen ◽  
Rolf Sommer Kaas ◽  
Frank M. Aarestrup ◽  
Sünje Johanna Pamp

Previous research has reported effects of DNA isolation, library preparation, and sequencing technology on metagenomics-based microbiome composition; however, the effect of biospecimen storage conditions has not been thoroughly assessed. We examined the effect of common sample storage conditions on metagenomics-based microbiome composition and found significant and, in part, systematic effects.


Sign in / Sign up

Export Citation Format

Share Document