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Zhu, Li, Xiaomeng Chong, Yu Zhao, Mingzhe Xu, and Lihui Yin. "Nanocomposite Detection of Elemental Impurities and Process Correlation Analysis of Ceftriaxone Sodium for Injection." Nanoscience and Nanotechnology Letters 12, no. 12 (December 1, 2020): 1458–63. http://dx.doi.org/10.1166/nnl.2020.3261.
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An inductively coupled plasma spectroscopy method was established to detect 29 elemental impurities in ceftriaxone sodium for injection by nanocomposite, and also used to detect the elemental impurities in the generic, domestic original and foreign original ceftriaxone sodium for injection. This paper for the first time analysed the possible sources of elemental impurities and their potential impacts on the drug quality based on the process. The results showed that zinc and potassium were detected in both the generic drug and the domestic original ceftriaxone sodium for injection, and zinc was not detected but potassium was detected in the foreign original drug; the content of zinc in the generic drug was significantly higher than that in the domestic original drug, and the content of potassium in generic drug and domestic original drug was higher than that in the foreign original drug, according to the process, the elemental impurities may come from the activated carbon or nanocarriers used in the process, and further stability analysis of the samples showed that the stability of the generic drug was slightly lower than that of the original drug, so it was speculated that impurity elements might also be one of the reasons for its instability.
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Dudenkova, M. E., L. N. Grushevskaya, M. S. Sergeeva, N. I. Avdyunina, B. M. Pyatin, K. V. Alekseev, E. V. Blynskaya, and E. Yu Karbusheva. "HPLC Determination of foreign impurities in tropoxin parent substance and tablets." Pharmaceutical Chemistry Journal 45, no. 12 (March 2012): 761–65. http://dx.doi.org/10.1007/s11094-012-0720-5.
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Litvinenko, A. V., R. I. Tarasova, and K. V. Pinyagin. "Quality control of phosphabenzide." Kazan medical journal 76, no. 3 (May 15, 1995): 204–5. http://dx.doi.org/10.17816/kazmj100639.
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The quality control of phosphabenzide (hydrazide of diphenylphosphinylacetic acid) as a pharmacopeial preparation is estimated by the following indices: specification, solubility, melting temperature, transparency and chrominance of solutions, iron, foreign impurities, quantitative determination on the basis of the complex of physical, physicochemical and chemical methods.
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Dobra, Gheorghe, Santiago Garcia-Granda, Sorin Iliev, Lucian Cotet, Hulka Iosif, Petru Negrea, Narcis Duteanu, Alina Boiangiu, and Laurentiu Filipescu. "Aluminum Hydroxide Impurities Occlusions and Contamination Sources." Revista de Chimie 71, no. 9 (September 5, 2020): 65–76. http://dx.doi.org/10.37358/rc.20.9.8318.
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This paper is reporting the data concerning impurities occlusion in the dried, milled and classified aluminum hydroxide, the sources of contamination and the ways to control the purity of classified aluminum hydroxide as raw material for special aluminas. Mainly, all the micronic size particles, floating in the super-saturated Bayer liquors, are potential sources of occluded impurities in the aluminum hydroxide particles. There are several mechanisms for embedding the impurities in crystalline substances. Of these, most probable ones in the Bayer alumina process are: a) occlusion of the spent liquor drops containing impurities inside the polycrystalline aluminum hydroxide congregates; b) hetero-nucleation of aluminum hydroxide on the surface of particles or colloids containing one or more impurities (the foreign particles are seized inside a crystals or inside of a crystalline multi-particulate association); c) incorporation of available ions or molecule reactive fragments in the poor crystalline structures of aluminum hydroxide after nucleation, during different growth stages of all already aggregated particles, under certain super-saturations. d) building up bridges between the scanty aggregated particles or filling the inside hollows of these aggregates with new quickly crystallized material, including the particulate impurities, mainly, during large fluctuations of the super-saturation. Using scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy EDS (Apollo SSD detector, EDAX), the contributions of each of these mechanisms can be investigated simply and assumed from the collected data. It was shown that well crystallized phases originating directly from bauxite (like the aluminum substituted goethite and substituted hematite, rutile or quartz), as well as the well as the crystallized new born phases during specific Bayer reactions (like cancrinite, are not promoting directly the impurities occlusion. Poor crystalline phases (like sodalite and katoite or other secondary phases and their micronic size fragments are really sustaining impurities occlusion through all the acknowledged mechanisms.
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Fedorov, Alexander V., Lada V. Yashina, Oleg Yu Vilkov, Clemens Laubschat, Denis V. Vyalikh, and Dmitry Yu Usachov. "Spin-polarized Fermi surface, hole-doping and band gap in graphene with boron impurities." Nanoscale 10, no. 48 (2018): 22810–17. http://dx.doi.org/10.1039/c8nr08339h.
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LAMSKOVA, M. I., M. I. FILIMONOV, Y. I. SUKHAREV, A. E. NOVIKOV, and S. V. BORODYCHEV. "OPTIMIZATION OF THE DESIGN-OPERATING PARAMETERS OF THE HYDROCYCLONE TAKING INTO ACCOUNT FIELD RESEARCH." Prirodoobustrojstvo, no. 4 (2020): 61–67. http://dx.doi.org/10.26897/1997-6011-2020-4-61-67.
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Cylindrical-conical pressure hydrocyclones are characterized by high productivity and efficiency indicators of water treatment from mechanical impurities at a relatively small size and cost, low resource costs for operation, which makes their use promising as a water treatment unit in the circulating water distribution systems of domestic and foreign industry. The purpose of the research is development of the construction of a filtering hydrocyclone and assessment of the impact of the fl ow characteristics and size of the sand pipe on the separative power of the apparatus in the process of water teratment from mechanical impurities. The presented design of the hydrocyclone apparatus with a filter drain pipe allows to increase water treatment rates from mechanical impurities including by trapping the smallest suspensions. As a result of experimental research of the effect of the flow characteristics and size of the sand pipe on the separative power of the apparatus, the technological and construction parameters of the PH-100 hydrocyclone with various versions of the drain pipe providing maximum efficiency of water treatment from mechanical impurities have been established. The graphoanalytic solution of the obtained regression equations has allowed us to establish that a hydrocyclone with a solid side wall drain pipe provides the maximum degree of water treatment from mechanical impurities at the level of 85.4% at a flow rate of 6.5 m3/h and a 12 mm diameter of the sand pipe. Replacing the standard construction drain pipe with a filtering side surface drain pipe increases the integral degree of water treatment from mechanical impurities to 96.4% with the same flow parameters and diameter of the sand pipe.
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Alexeeva, K. A., D. I. Pisarev, A. Yu Malyutina, and N. N. Boyko. "DEVELOPMENT OF METHODS FOR DETERMINATION OF SPECIFIC IMPURITIES IN THE GLUTATIONION RESTORED SUBSTANCE." Pharmacy & Pharmacology 6, no. 6 (January 6, 2019): 535–47. http://dx.doi.org/10.19163/2307-9266-2018-6-6-535-547.
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Glutathione (γ-L-glutamyl-L-cysteinylglycine) is the most important low molecular weight intracellular thiol tripeptide consisting of three amino acids – glycine, cysteine and glutamic acid. In Russian pharmacopoeia there is no regulatory documentation for glutathione, therefore, the development of a pharmacopoeial item for the specified substance is a relevant problem.The aim of the article is the development of methods for determining foreign specific impurities in glutathione.Materials and methods. The substance of glutathione reduced (CAS 70-18-8, EC 2007254, Applichem, Germany) containing impurities, and a standard sample of reduced glutathione (Sigma Aldrich, Japan) were used as the objects of the study. The analysis was carried out by using a high-performance liquid chromatography method in the reverse phase version and a thin layer chromatography method. The chromatography using RP HPLC was performed after preliminary derivatization of glutathione and its specific impurities with dancil chloride. Specific impurities in glutathione are dipeptides and amino acids. Therefore, they, like glutathione, can react with dancil chloride. Dancil derivatives are formed, and they can be determined by chromatographic separation.Results. As a result of chromatography by the method of RP HPLC of derivatized dancil chloride glutathione it has been established that this reaction makes it possible to detect impurities in it. Glutathione derivatives are well separated by chromatography by implementing the method of RP HPLC and have different absorption maxima. The glutathione derivative had an absorption maximum at λmax=284 nm. The derivatives belonging to specific glutathione impurities absorb at λmax=288 nm and λmax=296 nm. The data obtained using RP HPLC were confirmed by TLC in the isopropanol-water (2:1) system. Three components were found out, one of which corresponds to glutathione, while two others are impurities.Conclusion. Methods for determining impurities in the glutathione substance using RP HPLC methods with preliminary derivatization with dancil chloride and TLC with ninhydrin detection have been worked out. A comparative analysis of the data obtained makes it possible to state that the OF-HPLC method with pre-column derivatization is more reliable, since it is more sensitive to impurities, and also makes it possible to study the UV profiles of impurity components better than the TLC method. Therefore, for the detection of impurities in the substance of glutathione, it is more preferable to use RP-HPLC with pre-column derivatization. The results of this study can be recommended for inclusion in the regulatory documentation on the substance of glutathione in the section “Impurities”.
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Vyhnánek, Tomáš. "Polymorphism of prolamin proteins in selected varieties of winter wheat registered in the Czech Republic." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 56, no. 5 (2008): 221–26. http://dx.doi.org/10.11118/actaun200856050221.
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In 2006 and 2007 samples of harvested grain were used to verify the possibility of distinguishing 12 winter wheat genotypes and of detecting impurities on the basis of polymorphism of prolamin kernel proteins. Uniform electrophoretic patterns were detected in genotypes of Athlet, Buteo, Dromos, Ebi, Etela, Florett, Livia, Simila wheat in 2006 and 2007. On the basis of the identity index two sister prolamin lines with different share, depending on the year of harvest, were discovered in 3 wheat genotypes (Astella, Brea and Hana). The proportion of sister gliadin lines in the Astella and Brea genotypes was the same in both years. There was only minor difference (± 2.5%) in the share of the sister lines in the Hana variety between the respective years, and could be influenced by environmental factors. A foreign genotype was detected in the Mona variety. The identity index of the impurity to the Mona variety (ii = 0.30) was considerably low. In the impurity the gliadin block Gld 1B3 was not detected, which is the genetic marker of rye translocation T1BL.1RS (the Sr31 gene of resistance to black rust, higher cold resistance and the marker of poor baking quality – presence of secalin genes). The results proved the potential practical application of the electrophoretic detection of polymorphism of prolamin proteins as markers of impurities of foreign genotypes in a seed sample.
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Pivovarchyk, A. A., and Е. V. Pivovarchyk. "CONTROL OF CHEMICAL COMPOSITION OF CASTING BRASS IN INGOTS USED FOR MANUFACTURE OF STOP VALVES." Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY), no. 3 (October 10, 2017): 49–53. http://dx.doi.org/10.21122/1683-6065-2017-3-49-53.
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The article presents the results of a research of the chemical composition of brass foundry grade LS, supplied by domestic and foreign producers, as well as the chemical composition of brass lead grade LC4C used for the manufacture of stop valves. The research was made with use of optical emission spectrometers of various models and a scanning microscope. It was established that the pig delivered by the domestic producers corresponds to parameters of chemical composition for the pig’s foundry brand LS, while in the pig supplied by foreign producers there were found disparities of the chemical composition of certain basic elements. The results of the studies showed that the pig supplied by all producers, as well as the melt obtained with its use, contain in its composition such harmful impurities as S, Bi and P in the amount of 0.001%, 0.0017% and 0.0045%, respectively, that can lead to a decrease in the technological properties of products. It has been established that the use of ARL 3460 and OBLF-QSW 750 emission spectrometers and the Tescan VEGA II LMU scanning electron microscope makes it possible to obtain practically identical values of the content of the main elements and impurities in pigs of foundry and brass lead grade LC40C in studies on determining the chemical composition of the materials under study.
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Duddeck, Albrektsson, Wennerberg, Larsson, and Beuer. "On the Cleanliness of Different Oral Implant Systems: A Pilot Study." Journal of Clinical Medicine 8, no. 9 (August 22, 2019): 1280. http://dx.doi.org/10.3390/jcm8091280.
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(1) Background: This paper aimed to compare the cleanliness of clinically well-documented implant systems with implants providing very similar designs. The hypothesis was that three well-established implant systems from Dentsply Implants, Straumann, and Nobel Biocare were not only produced with a higher level of surface cleanliness but also provided significantly more comprehensive published clinical documentation than their correspondent look-alike implants from Cumdente, Bioconcept, and Biodenta, which show similar geometry and surface structure. (2) Methods: Implants were analyzed using SEM imaging and energy-dispersive X-ray spectroscopy to determine the elemental composition of potential impurities. A search for clinical trials was carried out in the PubMed database and by reaching out to the corresponding manufacturer. (3) Results: In comparison to their corresponding look-alikes, all implants of the original manufacturers showed—within the scope of this analysis—a surface free of foreign materials and reliable clinical documentation, while the SEM analysis revealed significant impurities on all look-alike implants such as organic residues and unintended metal particles of iron or aluminum. Other than case reports, the look-alike implant manufacturers provided no reports of clinical documentation. (4) Conclusions: In contrast to the original implants of market-leading manufacturers, the analyzed look-alike implants showed significant impurities, underlining the need for periodic reviews of sterile packaged medical devices and their clinical documentation.
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Wu, Xue Jing, and Qian Qiao. "Design of the Process and Equipment of Melt PEK Filter." Advanced Materials Research 605-607 (December 2012): 57–60. http://dx.doi.org/10.4028/www.scientific.net/amr.605-607.57.
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During the production of PEK, the dust and foreign matters will be bring into PEK by raw materials and refining process. The impurities enter into extrusion die can make runner block and make products incomplete, and then the application of PEK will be influenced. The following methods can be took to obtain pure PEK, PEK was first added to the extruder to melt, and then through the melt pump to increase the pressure, finally using certain mesh screen to filtrate. According to the request of filtration, a new filter device and process was designed.
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Zhao, Li Chun, and Min Peng Zhu. "Research of Key Techniques to Improve Quality and Yield in Inositol Production Process." Advanced Materials Research 750-752 (August 2013): 1463–67. http://dx.doi.org/10.4028/www.scientific.net/amr.750-752.1463.
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In inositol’s extraction process, the technological parameters and operational approaches of the following factors have a great influence on the final quality and yield: the quality and condition of raw material, acidolysis pressure, order of feeding and additives, use of neutralizer, removal of impurities in ion exchange section, vacuum degree in concentration section, evaporating temperature, outer steam pressure, purified washing and foreign ion tests. Though experiments, we concluded the key points and theoretical foundations to improve the products quality and yield. The results offer help for the actual production.
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Matveeva, L. Yu, M. V. Mokrova, V. I. Khirkhasova, and I. V. Baranets. "High-resolution optical microscopy study of the structure and morphology of nanocellulose used as microadditive to construction composites." Вестник гражданских инженеров 18, no. 1 (2021): 109–16. http://dx.doi.org/10.23968/1999-5571-2021-18-1-109-116.
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The article presents the study results of the structure and morphology of nanocellulose used as a microadditive to improve the physical and mechanical characteristics of mineral building binders and composites, with the investigation of a material sample having been performed by high-resolution optical microscopy. The investigations were performed in three optical modes, namely, phase contrast, light field, and crossed nicols. The dimensions of the primary structure elements and the aggregation nature of cellulose microfibers have been determined. The sample was also found to contain micro-impurities of a foreign chemical nature.
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Bobenko, Nadezhda, Yurii Chumakov, and Anna Belosludtseva. "Influence of Twist-Angle and Concentration Disorder on the Density of Electronic States of Twisted Graphene." Applied Sciences 12, no. 9 (April 19, 2022): 4109. http://dx.doi.org/10.3390/app12094109.
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In this paper, we present an approach that makes it possible to describe, from unified physical considerations, the influence of rotation-angle and concentration disorder on the density of electronic states of two-layer twisted graphene. The electron relaxation time and the density of electronic states near the Fermi level are calculated by considering the multiple elastic scattering of electrons by impurities and structural inhomogeneities of the short-range order type. An analysis is presented of the change in the contributions to the density of electronic states from electron scattering on foreign atoms with variations in the defectiveness of the structure, impurity concentration, temperature, and the external electric field magnitude. It is shown that the formation of short-range order areas by foreign atoms in the first coordination sphere relative to the surface of the material can lead to the opening of a gap in the density of electronic states of twisted graphene. Point defects and short-range order regions formed by foreign atoms in the second coordination sphere lead to metallization of twisted graphene.
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Lile, N. Liyana Tajul, Hasnul Hadi, and M. R. Roslan. "Vibration Analysis of Blocked Circular Pipe Flow." Applied Mechanics and Materials 165 (April 2012): 197–201. http://dx.doi.org/10.4028/www.scientific.net/amm.165.197.
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Pipes are found in almost all buildings and constructions where they are used to convey fluid to a desired location. Liquid containing foreign objects and impurities will sometimes creates unintentional built up or clog obstruction along the interior surface of the pipeline. This phenomenon may affect the fluid flow within the pipe. This work analyzed the impact of different blockage sizes inside a clear Polyvinyl Chloride (PVC) circular pipe using vibration measurement. Observations were made on the fluid flow patterns during the flow. This work encompasses the correlation between blockage thickness inside a circular pipe and vibration parameters.
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Rath, S., and S. N. Sahu. "Mercury-Telluride Nanocrystalline Thin Films: A Unique Photoluminescence in the Visible Regime." Journal of Metastable and Nanocrystalline Materials 23 (January 2005): 125–28. http://dx.doi.org/10.4028/www.scientific.net/jmnm.23.125.
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Stoichiometric mercury-telluride (HgTe) nanocrystals, free from any foreign impurities, have been prepared by an electrochemical technique. Transmission electron microscopy and selected area diffraction studies confirm that the size of HgTe nanocrystals with cubic phase range from 4 – 7 nm and are preferentially oriented. Optical absorption studies indicate that the band gap of HgTe nanocrystals is 2.14 eV. Room temperature photoluminescence measurements show band edge and trap dominated luminescence in the visible regime. Micro-Raman scattering analysis of the HgTe nanocrystals sample reveals the 1LO Raman vibrational mode is at 142.5 cm-1suggesting a shift of 6 cm-1 from it’s bulk value and confirms the crystalline size to be small.
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REDFIELD, DAVID. "DEFECTS IN AMORPHOUS Si:H — THE REHYBRIDIZED TWO-SITE (RTS) MODEL." Modern Physics Letters B 05, no. 14n15 (June 1991): 933–39. http://dx.doi.org/10.1142/s0217984991001167.
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A comprehensive model for the metastable defects in amorphous Si:H is developed by adapting a recent theory for several kinds of defects in crystalline semiconductors, particularly the DX center in AlGaAs. This new model accounts in a unified way for all of the major observations of defects induced by light, quenching, doping, or compensation; as well as for their anneal. The stretched-exponential time dependence of defect densities with light exposure or annealing, and saturation of the density are also explained. This model is based on foreign atoms rather than on breaking of Si-Si bonds, and in undoped materials it is suggested that unintentional impurities are the source.
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Evgenov, A. G., S. V. Shurtakov, S. M. Prager, and R. Yu Malinin. "ON THE DEVELOPMENT OF A UNIVERSAL CALCULATION METHOD FOR ASSESSING THE DEGRADATION OF RECYCLED METAL POWDER MATERIALS, DEPENDING ON THE CYCLICITY OF USE IN THE SELECTIVE LASER MELTING PROCESS." «Aviation Materials and Technologies», no. 4 (2020): 3–11. http://dx.doi.org/10.18577/2071-9140-2020-0-4-3-11.
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This article analyses foreign articles on the influence of the frequency of use on the level of impurities, technological characteristics of the powder in the SLM (DMLS) process and on the mechanical properties of the synthesized materials. A solution to the problem of developing a universal calculation method for evaluating degradation in the SLM process of recycled metal powder materials has been proposed. The algorithm includes the automatic correlation of the contamination factors with the corresponding exposure mode elements of each type of cross-section (contour, upskin, downskin, core) during measurement of the longitude of the laser path or the exposure duration of all elements that form the cross-section of a part.
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Ikram, M., and R. J. Singh. "EPR of VO2+, Cu2+ and Mn2+ Ions Doped in LiHSO4 Single Crystals." Modern Physics Letters B 17, no. 19 (August 20, 2003): 1067–71. http://dx.doi.org/10.1142/s0217984903006050.
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The EPR spectra of VO 2+, Cu 2+ and Mn 2+ ions doped in LiHSO 4 single crystals are reported. The foreign impurities appear to displace Li + ions, which are situated in voids formed by the hexagonal closest packing of bigger sulphate ions in the crystal structure. VO 2+ and Mn 2+ show characteristic hyperfine structure but no hyperfine splitting was observed in the spectra of Cu 2+ ions. It appears that VO 2+ and Mn 2+ are situated in one kind of void situated in an ordered way. The Cu 2+ ions may be occupying both kinds of voids, distributed in an irregular fashion. The molecular orbital binding coefficients β2 and α2 are calculated in the case of VO 2+.
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Rodrigues, Sandra Iara Furtado Costa, José Henrique Stringhini, Márcio Ceccantini, Antonio Mário Penz Júnior, Andrea Machado Leal Ribeiro, Vanessa Peripolli, and Concepta Margaret McManus. "CHEMICAL AND ENERGETIC CONTENT OF CORN BEFORE AND AFTER PRE-CLEANING." Ciência Animal Brasileira 16, no. 2 (June 2015): 158–68. http://dx.doi.org/10.1590/1089-6891v16i217226.
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The poultry industry normally has little control over the raw material that arrives at the processing plant. This experiment aimed to evaluate chemical and energetic quality of corn obtained in a feed mill before and after pre-cleaning. Twenty samples of 30 kg of corn each were taken from trucks delivering corn to the mill. The trucks were then unloaded and the material passed through a pre-cleaning process when another sample was taken. Samples were graded and physical properties evaluated: density (g/L), grain percentages of foreign material, impurities, fragments, broken, soft, insect damaged, fire-burnt, fermented, damaged, cracked and fine particles, as well as chemical composition analysis: Apparent metabolizable energy for poultry (AME), ether extract (EE), crude fiber (CF), starch (STA), water activity (WA), crude protein (CP), digestible and total lysine, methionine, cystine, threonine, tryptophan, valine, isoleucine, leucine, phenylalanine, histidine and arginine. The experiment was a randomized design with two treatments (before and after pre-cleaning) and twenty replications. Data was analyzed using SAS ® and treatment differences obtained using F test. Correlations and principal components were calculated. There was a decrease in density after the pre-cleaning process, which was probably due to the removal of earth and stones rather than grain and its fractions. Significant increases were found for insect damage, fermented and damaged grain while fire-burn was significantly reduced after the pre-cleaning process. Starch increased after pre-cleaning which is a result of contaminants that normally are poor in this carbohydrate, but fiber levels increased too. Apparent metabolizable energy, aminoacids, digestible (P<0.05) and total (P<0.05) histidine, total lysine and methionine (P<0.1) levels were reduced after pre-cleaning. Density was higher when there were fewer impurities such as straw, husk or small grains. Broken corn was positively correlated (P<0.05) with foreign material (0.63) and fragments (0.76), while proportion of damaged corn was positively correlated with foreign material (0.68), fragments (0.58) and broken corn (0.83). In this study, even in samples classified as excellent quality before pre-cleaning, the pre-cleaning process was effective in reducing humidity and water activity which helps control the growth of fungi or other microorganisms. Starch and fiber levels increased after pre-cleaning while apparent metabolizable energy levels was not improved by pre-cleaning.
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Masyutkin, Evgeniy, and Boris Avdeev. "EXPERIMENTAL STUDY OF COAGULATION OF PARTICLES IN A MAGNETIC SEDIMENTATION." Vestnik of Kazan State Agrarian University 15, no. 2 (September 8, 2020): 102–6. http://dx.doi.org/10.12737/2073-0462-2020-102-106.
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In agriculture, a large number of different lubricating and cooling liquids are used in the operation, maintenance and repair of agricultural machinery. In the process of use, technical fluids become contaminated with foreign impurities and require periodic cleaning. Magnetic sedimentation tanks are well suited for this. The studies were carried out in order to determine the parameters (the magnitude and gradient of the magnetic field strength, the height of the apparatus, the concentration of particles), at which coagulation of particles is observed in a non-uniform magnetic settler. The experiments were carried out on a laboratory setup for studying coagulation in the working area of a magnetic sump. For a given magnetic system, the geometric dimensions of the apparatus were determined in such a way that the magnetic field acts in the entire working volume of the sump and effectively traps foreign metal impurities. The value of the magnetic induction of the field B is proportional to the square of the distance from the investigated point to the pole of the electromagnet Н0. At a distance of 300 mm and further, the magnetic force has almost no effect on the particle, so the height of the sump should be less. The lowest magnetic induction is observed in the middle of the coil. A decrease in the current in the winding entails a reduction in the length of the floccule; magnetic coagulation takes place when the concentration of particles in the coolant is more than 0.3 g/l, with a lower content, it is not observed due to significant distances between the particles; the effect of coagulation is noted in the entire area of action of the magnetic field, while the length of the floccules decreases with a decrease in concentration. The distance at which the effect of coagulation between particles is observed is determined by a complex function that depends on the current in the winding, the field strength, their distance from the pole of the electromagnet, and also on the size of the particles.
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Rybchynskyi, R. "CHANGE OF STRESS CRACK IN CORN KERNEL DURING ITS PREPARATION FOR PROCESSING." Grain Products and Mixed Fodder’s 20, no. 2 (July 15, 2020): 14–18. http://dx.doi.org/10.15673/gpmf.v20i2.1760.
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The article presents the results of the study of the influence of stress crack in corn kernel on the change of its mechanical properties, namely, on the strength of kernel and its ability to grind during the technological process of preparation for processing. The research was conducted at the Dnipro Food Concentrates Plant. It is established that percentage of damage, i.e. grain impurities and foreign material (impurities), when receiving grain at the production elevator is within the norms of State standards of Ukraine (DSTU 4525:2006) – up to 7 % and not more than 1.0 %, respectively. But in the process of grain transportation this index is increasing. The maximum level of grain impurities (9.1 %) in corn grain can be observed before its preliminary cleaning on the separator BSH-100, then this indicator decreases significantly to 1.8 % in the cleaned grain, but then increases again in the technological process. Moreover, before sending grain into the degerminator the level totals 4.8 % - almost as much as when receiving grain from vehicles. One can say the same regarding the level of foreign material. Its minimum amount in the grain after pre-cleaning (0.5 %), and the maximum – at the end of the cleaning stage (7.4 %), which is much more than when receiving grain. The increase in the amount of broken grain (including that relating to impurities) in the technological process is accompanied by higher number of stress cracks in the corn kernel. During receiving, the studied grain has already had a high stress crack – 68 %. At the same time, there was more corn kernel with one crack (41 %). After transportation by a belt conveyor and the main high-performance bucket elevator, although the total stress crack increased not significantly – up to 75 %, but there were changes in the number of cracks: the number of kernels with one crack decreased to 22 %, but the number of kernels with many (three or more) cracks increased from 8 to 33 %, respectively. During further transportation and processing of corn kernel, the stress crack increased to a maximum value of 78 % (before separation on SAD-10-01), and then decreased to 72 % in the grain entering the degerminator. It is established that the decrease in corn kernel strength is influenced by both the total stress crack and its nature, i.e. the number of stress cracks in each kernel. The maximum required force for the corn kernel damage was observed exactly for grain entering the intake pit – 3.6 kg / 50 kernels. Here you can find more corn kernels stressed by only one crack (single) – 41 % or without cracks – 32 %. And the minimum effort – 3,0 kg / 50 kernels - for cleaned grain after conveyor and elevator No. 1, where the share of kernels with multiple stress crack (3 or more cracks) totaled 43 % (only 22 % of kernels were without cracks). A high inverse correlation of -0.84 was established between the number of stressed kernels with three or more cracks and the effort to break corn kernel. Based on research, it is recommended to use the index of stress crack in corn kernel to assess its quality when accepted for further processing, as this indicator is directly related to the yield of finished products. Key
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Stroescu, Gheorghe, Anişoara Păun, Gheorghe Voicu, Carmen Brăcăcescu, Radu Popa, and Vlad Popa. "Researches on the separation of impurities from a seed flow based on the aerodynamic principle." E3S Web of Conferences 112 (2019): 03011. http://dx.doi.org/10.1051/e3sconf/201911203011.
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Ensuring for production the necessary quantities of biological material of valuable varieties and hybrids to maintain their initial characteristics requires the permanent application of measures to be carried out on a scientific basis, depending on the biological particularities of the variety or hybrid. The production of seeds for leguminous plants is of great importance because the vast majority of species propagate that way. Due to the fact the yield obtained depends on the quality of the seeds, it is necessary to use seeds of varieties and hybrids with superior qualities and from higher biological categories without foreign bodies (impurities). Knowing the particularities of leguminous plant seed is of special practical importance because the conditioning technologies and machinery are based on it and also the culture technologies that are applied both in the field and in protected areas. The paper presents some theoretical aspects regarding the separation of seed mixtures based on the aerodynamic principle (resistance of the seed mass layer to the air passage, seed floating capacity, air flow working rates, total air flow, physical characteristics of seeds, etc.) which were the basis for designing a conditioning module for vegetable, flower and cereal seeds.
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Stankovic, Zvonimir, Vladimir Cvetkovski, and Vesna Grekulovic. "The effect of bi presence as impurities in anodic copper on kinetics and mechanism of anodic dissolution and cathodic deposition of copper." Chemical Industry 64, no. 4 (2010): 337–42. http://dx.doi.org/10.2298/hemind100329021s.
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The influence of Bi, as foreign metal atoms in anode copper, on kinetics and mechanism of anodic dissolution and cathodic deposition of copper in acidic sulfate solution was investigated using the galvanostatic single-pulse method. Results indicate that presence of Bi atoms in anode copper increases the exchange current density, as determined from the Tafel analysis of the electrode reaction, which is attributed to the increase of the crystal lattice parameter determined from XRD analysis of the electrode material.
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HARDING, FELIPE A., NELSON A. ALARCON, and PEDRO G. TOLEDO. "AFM AND XPS CHARACTERIZATION OF ZINC–ALUMINUM ALLOY COATINGS WITH ATTENTION TO SURFACE DROSS AND FLOW LINES." Surface Review and Letters 08, no. 05 (October 2001): 513–19. http://dx.doi.org/10.1142/s0218625x01001294.
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Surfaces of various zinc–aluminum alloy (Zn–Al) coated steel samples are studied with attention to foreign surface dross by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS/ESCA). AFM topographic maps of zinc–aluminum alloy surfaces free of dross reveal the perfect nanoscale details of two kinds of dendrites: branched and globular. In all magnifications the dendrites appear smooth and, in general, very clean. XPS analysis of the extreme surface of a Zn–Al sample reveals Al, Zn, Si and O as the main components. The XPS results show no segregation or separation of phases other than those indicated by the ternary Al–Zn–Si diagram. For surfaces of Zn–Al plagued with impurities, high resolution AFM topographic maps reveal three situations: (1) areas with well-defined dendrites, relatively free of dross; (2) areas with small, millimeter-sized black spots known as dross; and (3) areas with large black stains, known as flow lines. Dendrite deformation and dross accumulation increase notably in the neighborhood, apparently clean to the naked eye, of dross or flow lines. XPS results of areas with dross and flow lines indicate unacceptable high concentration of Si and important Si phase separation. These results, in the light of AFM work, reveal that dross and flow lines are a consequence of a high local concentration of Si from high melting point silica and silicate impurities in the Zn–Al alloy source.
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Yang, Ming Fu, Min Lin Huang, and Ming Jong Tsai. "Multi-Objective Optimization of Cleaning Process for LAO Wafers Using Grey Relational Analysis." Advanced Materials Research 579 (October 2012): 260–68. http://dx.doi.org/10.4028/www.scientific.net/amr.579.260.
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The light emitting diode (LED) development technology is an important topic for green industry. This study focused on the efficient cleaning for LAO hydrolysis material, which is a potential LED substrate. The 99.5% ethanol or an alternative solution is used to clean the LAO substrate and dry with the help of anhydrous gas. To improve the cleaning performance, the Taguchi-based orthogonal array of experimental planning and the Grey Relation Analysis are employed to optimize the cleaning parameters. Four control factors are cleaning time, soaking time, PVA sponge type, drying method. The multiple performance characteristics of responses include the residual traces of impurities and water mark after the cleaning process for LAO substrate. With the proposed cleaning process, the surface foreign matter removal rate of target 80% and the residual water marks of declining to 20% are achieved.
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Olšovská, Jana, Lucie Kyselová, Petra Kubizniaková, and Martin Slabý. "Non-microbiological turbidity of beer: Part 1 – semireview." KVASNY PRUMYSL 67, no. 4 (August 15, 2021): 484–97. http://dx.doi.org/10.18832/kp2021.67.484.
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Beer is a complex mixture consisting of hundreds of chemical substances. Some of them are macromolecules, such as proteins and polysaccharides that together with polyphenolic compounds form poorly soluble complexes causing beer turbidity or cold colloidal turbidity. Furthermore, beer turbidity can be caused also by procedural particles entering into beer during brewing process (filtration and stabilization aids) or by foreign particles from external environment (mechanical impurities). If turbidity, sediment or individual particles occur in filtered and stabilized beer, their origin must be determined since brilliant visual impression of the filtered beer influences an opinion of customers on a specific product. The identification of different species of turbidity using microscopic image, particle staining, enzymatic analysis or identification precursors is clearly described in this paper. The study includes pictorial documentation of various particles that may be part of beer turbidity.
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Vyhnánek, T., and J. Bednář. "Detection of the varietal purity in sample of harvested wheat and triticale grains by prolamin marker." Plant, Soil and Environment 49, No. 3 (December 10, 2011): 95–98. http://dx.doi.org/10.17221/4096-pse.
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In 1997 and 1998 we used samples of harvested grain to verify the possibility of distinguishing 14 winter wheat genotypes and six triticale genotypes and detecting the impurity on the basis of the detection of polymorphism of prolamin kernel proteins using the methods of the PAGE ISTA. On the basis of the identity index two sister prolamin lines with different percentage of participation, which was based on the weather conditions of the year of harvest, were discovered in seven wheat genotypes (Astella, Brea, Hana, Ilona, Siria, Sofia and Šárka) and two triticale genotypes (Tornádo and KM 779). A foreign genotype was detected in the Hana and Astella varieties. The identity index of the impurity to the Astella and Hana variety (i.e. ii = 0.28 and ii = 0.20, respectively) was considerably lower. In an unknown genotype (impurity) we detected the gliadin block Gld 1B3, which is the genetic marker of rye translocation T1BL.1RS, the Sr31 gene of resistance to black rust, higher cold resistance and the marker of poor baking quality (presence of secalin genes). The results proved the potential practical application of the method of electrophoretic detection of polymorphism of prolamin proteins as markers of impurities of foreign genotypes in a seed sample.
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Maia, Luciana Furlaneto, and Raissa Curti Bonfante. "Microscopic analysis of minas frescal cheese sold in city of Londrina-PR." Revista Brasileira de Pesquisa em Alimentos 2, no. 1 (October 2, 2011): 45. http://dx.doi.org/10.14685/rebrapa.v2i1.16.
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<p>Cheese are considered highly perishable foods, so it must be produced with raw materials of good quality, subject to an efficient quality control, besides their transport, storage and marketing appropriate to avoid vehiculation of diseases. The presence of impurities in food may be indicative of neglect at some point in the process, moreover, the insects and mites can act as backers of microbiological contaminants such as fungi, bacteria, viruses, protozoa and helminths. This study aimed to verify the hygienic conditions of Minas frescal type cheese sold in food markets in the city of Londrina-PR, according to the nature and amount of foreign material (dirt) present. Twenty samples of cheese were washed with kerosene and filtered on filter paper, whose content was analyzed retained a standard optical microscope (increased 400 times). The results showed that 100% of the samples contained at least one type of foreign matter, demonstrating poor hygienic quality. These date showed that is important to monitor these products since they can be vehicles of diseases, endangering the health of consumers.</p><p> </p><p>DOI: <a href="http://dx.doi.org/10.14685/rebrapa.v2i1.16">http://dx.doi.org/10.14685/rebrapa.v2i1.16</a></p>
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Rudniev, V. A., A. F. Klimchuk, O. S. Dontsova, P. V. Karnozhitskyi, and A. O. Kyzminyh. "COMPREHENSIVE EXPERT RESEARCH ON SOLVENTS FOR FLEXOGRAPHY ON ETHANOL BASIS." Theory and Practice of Forensic Science and Criminalistics 18 (December 26, 2018): 576–85. http://dx.doi.org/10.32353/khrife.2018.67.
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Application of gas chromatography allows obtaining basic data on the mixture composition, that is revealing the main component, discovering availability of impurities of macro- and microcomponents at qualitative and quantitative levels. It is possible to obtain data on the presence of moisture using IR spectroscopy. Quantitative parameters on the presence of water can be obtained using titration methods аccording to K. Fisher or using gas chromatography with a thermal conductivity detector. Density parameters and fraction composition allows revealing (indirectly) the presence of other impurities, as well as establish conformity of the object under research to requirements of the relevant normative and technical documentation. The obtained complex is sufficient for the formation of conclusions in categorical form and does not require additional data provided that the following signs are met, which include: 1. Presence of ethyl alcohol as the main component (usually more than 90 %). 2. Dehydration is one of the key indicators that allows the use of solvent for flexography. 3. Presence of components added to ethanol to provide the required volatility (eg, esters). 4. Low content of heavy (high boiling) components. The paper considers differences of solvents for flexography from other similar objects that can be important for expert research. Besides differences in the composition and properties of considered products, also the differences in the characteristics of the goods in the Ukrainian classification of goods of foreign economic activity are demonstrated. An example of use of data obtained as a result of chemical research, by an commodity expert in formulating categorical conclusions on delivered question is offered.
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Dorokhov, Alexey Semyonovich, Aleksey Viktorovich Sibirev, Alexander Gennadievich Aksenov, and Maxim Alexandrovich Mosyakov. "LABORATORY-FIELD RESEARCH RESULTS FOR ONION CLEANING." INMATEH Vol.61 61, no. 2 (August 31, 2020): 41–48. http://dx.doi.org/10.35633/inmateh-61-05.
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In the machine technology for cultivation and harvesting of root crops and onions, one of the most important quality indicators determining the duration of root crops storage is the presence of soil and plant impurities in the heap to be stored. The impossibility to separate soil lumps from the heap of root crops and onions is due to the fact that the majority of harvesters use slotted separating executive devices, while the inter-rod distance of the separating conveyor, in order to eliminate the loss of root crops, is made smaller than the minimum size of the separated root crop, which leads to the impossibility of their cleaning on the separating executive devices of harvesters, and, consequently, to the damage of a significant part of commercial products and loss of a significant part of the crop grown during storage. The modern technologies and technical means for harvesting root crops and onions are not capable of providing high-quality commercial products with minimal labour, due to falling behind or a lack of development of technological foundations, technologies and executive devices for harvesting root crops and onions, capable of reducing or excluding the content of soil lumps in commercial products under various soil and climatic conditions. Therefore, development of mechanization tools for harvesting root crops and onions, which would allow reducing or eliminating the content of mechanical impurities in commercial products under various soil and climatic conditions, is a scientific problem, the solution of which will contribute to the innovative development of the domestic agricultural market, Russia's stable position on the foreign market.
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Baral, Sasmita, and Dhiraj Kumar Nanda. "Risk and benefits of consuming raw (unpackaged) and pasteurized (packaged) milk." DRC Sustainable Future: Journal of Environment, Agriculture, and Energy 1, no. 1 (March 5, 2020): 23–32. http://dx.doi.org/10.37281/drcsf/1.1.4.
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The aim of this review is to overview important literature data on milk and its composition, methodology of quality assurance throughout its processing and preservation, and to compare risks and benefits of consuming raw (unpackaged) and pasteurized (packaged) milk. Milk contamination risks are of various types, including physical contamination (foreign components, such as manure, feed, dust, pieces of broken glass, strands of hair, wood, plastic, or metal chips), chemical impurities (antibiotics, hormones, pesticides, detergents, or heavy metal residues), and microbiological agents (germs and somatic cells). Our study addresses the quality and safety of raw and pasteurized milk consumed by humans. If one considers risks and benefits simultaneously, there are many pros and cons of consuming raw and pasteurized milk. One can conclude that pasteurized milk is more appropriate for consumption as compared to the lower quality raw milk. For manufacturing high quality pasteurized milk, one should implement good hygienic practices, proper pasteurization process, as well as pre and post pasteurization preservation.
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Bydałek, Franciszek, Anna Kula, and Jacek Mąkinia. "Morphology and Elemental Composition of Product Obtained from Struvite Fluidized Bed Reactor." Civil and Environmental Engineering Reports 28, no. 2 (June 1, 2018): 139–49. http://dx.doi.org/10.2478/ceer-2018-0025.
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Abstract Phosphorus scarcity is no longer a distant future, therefore the idea of phosphoru recovery is currently widely adopted and developed. Technologies based on the struvite precipitation are consider to address the future P challenges in the optimum way. This paper presents the results of the pilot scale implementation of fluidized bed reactor for struvite precipitation at the wastewater treatment plant. The test was carried out to assess the applicability of the technology in terms of robustness and final product quality, operating at low pH level (7,5-7,8). Obtained struvite pellets were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) with an energy dispersive spectrometer (EDS). The presence of foreign ions and particulate impurities in the feed source, affected the uniform growth of the crystal structure, resulting in highly porous structure of the pellets. Despite the varying physiochemical conditions, typical for wastewater, obtained pellets were determined with 95% struvite purity.
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Afinogenov, I. A., I. A. Zeltser, E. B. Trunin, and A. Tolstoguzov. "Characterization on Contacting Surfaces of MEMS Electrostatic Switches by SEM, EDXA, and XPS." Advances in Materials Science and Engineering 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/679313.
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We focus on the origin and sources of surface contamination and defects causing the failure of MEMS electrostatic switches. The morphology, and elemental and chemical compositions of the contacting surfaces, conducting paths, and other parts of switches have been characterized by means of SEM, EDXA, and XPS in order to understand the difference between the data collected for the devices that had passed the electrical conductivity test and those found to be defective. C, O, Al, Ca, Ti, Cu, and some other impurities were detected on the details of defective switches. Contrariwise, the working switches were found to be clean, at least on the level of EDXA and XPS sensitivity. The main sources of surface contamination and defects were incompletely deleted sacrificial layers, substrate materials, and electrolytes employed for Rh plating of the contacts. The negative influence of foreign microparticles, especially alumina and copper oxides, on the conductivity and porosity of contacts was highlighted.
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LÖFFELMANN, M., and A. MERSMANN. "A NEW METHOD FOR SUPERSATURATION MEASUREMENT: IDEA, IMPLEMENTATION AND RESULTS." International Journal of Modern Physics B 16, no. 01n02 (January 20, 2002): 391–98. http://dx.doi.org/10.1142/s0217979202009913.
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Up to now supersaturation measurement can be generalized as using physical properties that show a dependence on concentration as measurands for supersaturation. Impurities, foreign particles or ions influence the metastable zone width as well as the kinetics of nucleation and crystal growth, but most of the existing measurement methods are not able to incorporate those disturbances in the measured supersaturation. Therefore, a supersaturation sensor considering the actual crystallization process itself has been developed. The idea of the new supersaturation sensor is to induce crystallization on the sensor surface by generating an additional supersaturation by cooling and to observe the time-dependent development of the incrustation. Assuming a constant cooling rate and constant properties of the sensor surface the starting time of the incrustation on the sensor surface depends only on the prevailing supersaturation in the process solution. Experimental results obtained for inorganic ( KNO 3) and organic (Adipicacid) crystallizing solutes proved the applicability of the new sensor.
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Ivanov, Igor E., Vladislav S. Nazarov, and Igor A. Kryukov. "Application of the Moment Method for Numerical Simulation of Homogeneous-Heterogeneous Condensation." Fluids 7, no. 2 (February 7, 2022): 68. http://dx.doi.org/10.3390/fluids7020068.
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The paper considers the numerical modeling of the processes of homogeneous and heterogeneous condensation and evaporation in multiphase flows using the method of moments. Nonstationary processes of gas dynamics and phase transitions in the two-dimensional plane and axisymmetric regions are described by a general system of equations. The system of equations is expanded by adding two equations. One describes the evolution of the total mass fraction of the condensing substance; the other describes the evolution of the mass fraction of solid particles. An instant wetting model is used to model heterogeneous nucleation. The Gyarmathy model is used for the approximation of the average droplet growth rate. Heterogeneous condensation is modeled based on the distribution function of foreign impurities. An approach to calculating evaporation in the heterogeneous case is proposed. A comparison of the proposed models with a numerical experiment is given. Numerical simulation of homogeneous-heterogeneous condensation in a gas-dynamic ejector is carried out.
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Alkhedher, Mohammad, Abdul Majid, Niyazi Bulut, and Samah Elsayed Elkhatib. "Ab Initio Study on Dopant Relaxation Mechanism in Ti and Ce Cationically Substituted in Wurtzite Gallium Nitride." Materials 15, no. 10 (May 18, 2022): 3599. http://dx.doi.org/10.3390/ma15103599.
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The changes in properties of materials upon introduction of impurities is well documented but less is known about the location of foreign atoms in different hosts. This study is carried out with the motivation to explore dopant location in hexagonal GaN using density functional theory based calculations. The dopant site location of the individual dopants Ti, Ce, and Ti-Ce codoped wurtzite GaN was investigated by placing the dopants at cationic lattice sites as well as off-cationic sites along the c-axis. The geometry optimization relaxed individual dopants on cationic Ga sites but in the case of codoping Ce settled at site 7.8% away along [0001 ¯] and Ti adjusted itself at site 14% away along [0001] from regular cationic sites. The analysis of the results indicates that optimized geometry is sensitive to the starting position of the dopants. The magnetic exchange interactions between Ti and Ce ions are responsible for their structural relaxation in the matrix.
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Moiseev, S. V., N. E. Kuz’mina, and A. I. Luttseva. "NMR as Used in the Russian and Foreign Pharmacopoeias for Quality Control of Medicinal Products." Bulletin of the Scientific Centre for Expert Evaluation of Medicinal Products 12, no. 1 (February 18, 2022): 8–23. http://dx.doi.org/10.30895/1991-2919-2022-12-1-8-23.
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The ongoing development of the Pharmacopoeia of the Eurasian Economic Union and the current trend for harmonisation of the Russian Pharmacopoeia with the world leading pharmacopoeias suggest the necessity of studying how different pharmacopoeias use nuclear magnetic resonance (NMR) for quality control of medicinal products. The aim of the study was to compare the extent of medicine quality characteristics assessed by NMR in the Russian and foreign pharmacopoeias. The review summarises the experience of various national and world pharmacopoeias in using the NMR method for quality control of medicines and certification of pharmacopoeial reference materials. The comparative analysis covered the following quality parameters: active ingredient identification, determination of the composition of non-stoichiometric compounds, determination of the average polymer chain length in polymers and block copolymers, determination of the absolute content of the active ingredient, identification and quantification of impurities, polymorphism, and crystallinity. It was shown that the United States and Japanese Pharmacopoeias are leading the way in introducing the NMR method into pharmacopoeial analysis. There have been some positive trends in the introduction of the NMR method in the State Pharmacopoeia of the Russian Federation as well. It was concluded that changes are needed in the general chapters “Nuclear Magnetic Resonance Spectroscopy” and “Reference Standards” of the State Pharmacopoeia of the Russian Federation, 14th ed. in order to harmonise the texts with those of the Eurasian Pharmacopoeia and the European Pharmacopoeia and to allow for the possibility of direct identification of a substance by complex analysis of NMR spectral data, without comparing the test sample and the reference standard spectra. The NMR method should be included in the list of absolute methods used for determination of purity of primary chemical reference substances during certification.
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Atamanyuk, A. A. "PROBLEMS OF OPERATION OF GAS PURIFICATION PLANTS CONTAINING ORGANIC COMPOUNDS." Journal of Coal Chemistry 1 (2020): 23–28. http://dx.doi.org/10.31081/1681-309x-2020-0-5-23-28.
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The article analyzes the current state and perspectives of the modernization of existing plants for the purification of the technological gases from organic impurities. It has been shown that the main technical solution for organizing such purification since the 90s is the installation of thermocatalytic equipment. According to the design documentation, the efficiency of purification from organic compounds has to be about 90 %. Such plants are still in operation, but they are ineffective because of a number of reasons. With the involvement of qualified specialists from the Research Institute of the SE "UkrNTTS "Energostal", an assessment was made of the current state of the operating gas purification plants, in particular, the thermocatalytic gas purification units (GPU) from organic impurities at a number of coke-chemical plants. The survey was accompanied by technical consultations in order to bring the operation of the existing units to the design parameters. Assessment of the current state of the facilities showed that they do not operate in design regimes and that bringing them to design indicators will require significant capital expenditures. A detailed analysis of this problems shows that under the current conditions it is practically impossible to ensure the trouble-free operation of such a plants. Recommendations have been formulated for the alternative processes for sanitary cleaning of gases from organic compounds by gases gathering in global collector and involvement in industry recycling, based on examples of foreign and domestic analogues (including implemented on PJSC "ArcelorMittal Kryvyi Rih"). The issues have been touched upon the application of the domestic experience of implementation of more advanced thermocatalytic gas purification units. As an example of the operation of such a plant, a gas purification system with a capacity of 1300 m3 /h from a pitch granulation plant implemented at PJSC “ZAPOROZHKOKS” has been given.
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Iszhan, Nashrin, Farah Nurshahida Mohd Subakir, and Nazikussabah Zaharudin. "Determination of Proximate Composition of Malaysian Horseshoe Crab (Tachypleus gigas)." Materials Science Forum 1025 (March 2021): 128–33. http://dx.doi.org/10.4028/www.scientific.net/msf.1025.128.
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This study was conducted to investigate proximate content of horseshoe crab (Tachypleusgigas) in Malaysia. To date, there has been little agreement on what the nutrition value of horseshoe crab is and how it will benefit the consumers. The samples were divided by two parts, which are roe and muscle. The Tachypleusgigas was cleaned of foreign materials and impurities manually by human hand. The samples were ground into flour and sieved through 50 μm sieve and were packaged in airtight plastic bags prior to analyses. The horseshoe crab was analyzed for its proximate composition of different body parts. The results showed that the roe and muscle of Tachypleusgigas contained moisture (50.45 % and 73.67 %), ash (0.41 % and 2.72 %), crude proteins (38.24 % and 14.62 %), crude fats (9.30 % and 8.09 %), carbohydrates (1.67 % and 0.91 %) and energy (241.42 Kcal/100 g and 134.43 Kcal/100 g), respectively. This shows that roe has better nutrition content since it has higher protein, fat and carbohydrate content, which are the main energy-providing nutrient. Overall, the proximate content of Tachypleusgigas was nearer to the shellfish rather than the finfish and can be considered as a good nutrition source.
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ZAMBIASI, MILENA ANA, PAULO RICARDO DE JESUS RIZZOTTO JÚNIOR, RAFAEL GOMES DIONELLO, LAURI LOURENÇO RADUNZ, and INDIANARA MULLER. "PHYSICAL AND TECHNOLOGICAL QUALITY OF CORN KERNELS DURING STORAGE AS A FUNCTION OF PRE-CLEANING." Revista Brasileira de Milho e Sorgo 19 (June 23, 2020): 14. http://dx.doi.org/10.18512/rbms2020v19e1159.
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Maize is the most cultivated and consumed cereal in Brazil, which is the world’s third largest producer of this grain. Estimated losses due to pest attack, especially pest insects and fungi, represent approximately 10% of the total production. The pre-cleaning phase allows the reduction of foreign matters and impurities (IM) present in the grains, which are used as food and shelter for stored grain pests. The aim of this work was to evaluate the effect of pre-cleaning on the physical and technological quality of corn kernels, during bulk storage in a silo-dryer. The grains were harvested with a combine harvester, at a moisture content of around 17% and 0.84% of IM. Part of the grains was submitted to pre-cleaning and subsequently stored in a silo, while the other part was directly stored in a silo-dryer. After pre-cleaning, the grains were sent to the silo-dryer with 0.12% of IM. Drying was carried out by blowing natural air through the grain and the process was completed when the grains reached approximately 12% moisture content. It was concluded that pre-cleaning provided lower hygroscopic equilibrium moisture, reduced the presence of insect damaged grains, and improved the technological classification of grains during storage.
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Mottana, Annibale, Takatoshi Murata, Augusto Marcelli, Giancarlo Della Ventura, Giannantonio Cibin, Ziyu Wu, and Richard Tessadri. "Characterization of Local Chemistry and Disorder in Synthetic and Natural α-Al2O3Materials by X-ray Absorption Near-Edge Structure Spectroscopy." Journal of Applied Crystallography 31, no. 6 (December 1, 1998): 890–98. http://dx.doi.org/10.1107/s0021889898007778.
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X-ray absorption fine spectra at the AlKedge were measured experimentally and calculated theoreticallyviathe multiple-scattering formalism for chemically pure and physically perfect synthetic α-Al2O3(α-alumina), natural ruby/sapphire (corundum) and a series of artificial corundums produced for technical purposes and used as geochemical standards. The AlK-edge spectra differ, despite the identical coordination (short-range arrangement) assumed by O around Al, and vary slightly in relation to the slightly different chemistries of the materials (substitutional defects) as well as on account of the location taken by foreign atoms in the structural lattices (positional defects). A quantitative treatment of the observed changes is made in terms of short-range distortion of the coordination polyhedron and of medium- to long-range modifications in the overall structure, both induced by substitutions. In some technical corundums, the impurities of admixed β-alumina, where Al is both in fourfold and sixfold coordination, produce another small but detectable effect on AlKedges. Therefore, XAFS spectroscopy proves its potential for both measuring a light element such as Al and detecting minor coordination changes and dilute substitutions (∼1–3 wt% as oxide) of the absorber by other atoms, at least under the favourable conditions occurring in this system.
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Zhang, Chengliang, Tianhui Li, and Wenbin Zhang. "The Detection of Impurity Content in Machine-Picked Seed Cotton Based on Image Processing and Improved YOLO V4." Agronomy 12, no. 1 (December 28, 2021): 66. http://dx.doi.org/10.3390/agronomy12010066.
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The detection of cotton impurity rates can reflect the cleaning effect of cotton impurity removal equipment, which plays a vital role in improving cotton quality and economic benefits. Therefore, several studies are being carried out to improve detection accuracy. Image processing technology is increasingly used in cotton impurity detection, in which deep learning technology based on convolution neural networks has shown excellent results in image classification, segmentation, target detection, etc. However, most of these applications focus on detecting foreign fibers in lint, which is of little significance to the parameter adjustment of cotton impurity removal equipment. For this reason, our goal was to develop an impurity detection system for seed cotton. In image segmentation, we propose a multi-channel fusion segmentation algorithm to segment the machine-picked seed cotton image. We collected 1017 images of machine-picked seed cotton as a dataset to train the detection model and tested and recognized 100 groups of samples, with an average recognition rate of 94.1%. Finally, the image segmented by the multi-channel fusion algorithm is input into the improved YOLOv4 network model for classification and recognition, and the established V–W model calculates the content of all kinds of impurities. The experimental results show that the impurity content in machine-picked cotton can be obtained effectively, and the detection accuracy of the impurity rate can increase by 5.6%.
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Sokolenko, L. V., T. M. Sokolenko, Yu L. Yagupolskii, V. I. Kalchenko, Yu V. Veresenko, O. V. Nenia, Yu D. Kuchynskyi, et al. "Narcotic Drug Smell Mimics for Dog Training at Cynological Departments: Composition, Principle of Action, and Legal Frame work of their Use." Science and innovation 16, no. 5 (October 30, 2020): 71–78. http://dx.doi.org/10.15407/scine16.05.071.
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Introduction. Involvement of cynological departments to narcotics identification is widely used due to high sensitivity of canine olfaction. Problem Statement. Currently, cynological departments of the MIA of Ukraine can use the samples of original narcotics in detector dogs learning and training for the purpose of developing or maintaining of the corresponding skill. However, narcotics are the substances under control; therefore, special normative procedures for their obtaining, usage, storage, and utilization exist. This order greatly complicates dogs training. The use of original narcotics is reasonable in special cynological schools during basic learning of detector dogs. Further training in departments is oriented to maintain skills and, as a rule, is carried out using pseudo narcotic scents, which does not contain original narcotics and does not possess narcotic activity. Majority of such pseudo narcotic scents is of foreign production and are expensive. This fact does not allow to provide with training aids all the cynological departments of the MIA of Ukraine. Moreover, these pseudo narcotic scents are of limited range. Purpose. The purpose of this research is to develop domestic pseudo narcotic scents with extended range, which would not possess narcotic activity, but have similar odor properties like original narcotics and are cheaper in comparison to foreign counterparts. Materials and Methods. Pseudo narcotic scents of cocaine, heroin, marijuana, methamphetamine, opium, and poppy straw were developed. These training aids consist of inert carrying agent and volatile organic impurities from narcotics. These training aids were tested with involvement of 12 detector dogs of the cynological departments of the National Policy of Ukraine and State border service of Ukraine. Results. Pseudo narcotic canine training aids for cocaine, heroin, marijuana, methamphetamine, opium, and poppy straw were created and tested with detector dogs. It was shown that odorological profile of pseudo scents agreed with original narcotics. Conclusions. Pseudo narcotic scents which are perspective for introduction into production and further usage as canine training aids in cynological departments have been established.
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Polygalov, Stepan, Galina Ilinykh, Vladimir Korotaev, Nemanja Stanisavljevic, and Bojan Batinic. "Determination of the composition and properties of PET bottles: Evidence of the empirical approach from Perm, Russia." Waste Management & Research: The Journal for a Sustainable Circular Economy 39, no. 5 (April 17, 2021): 720–30. http://dx.doi.org/10.1177/0734242x211011222.
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Efficient collection systems and information about the characteristics and quality of collected secondary plastic waste flows are of fundamental importance for the development of circular economies. In order to assess the effectiveness of the implementation of separate collection systems for plastic packaging, especially polyethylene terephthalate (PET) bottles, characteristic of the collected PET bottles in street mesh containers were studied in the city of Perm, Russia. The share of extraneous fractions was assessed and differentiation was carried out by volume, type of product, label presence, shape, content of solid and liquid impurities and colour. These results indicate that PET composition in different seasons is very similar, despite the assumption that the consumption of PET bottles in the spring and autumn seasons varies. In the mesh containers, up to 34% of the items were foreign objects, considering that only PET bottles should be collected. In each dimensional flow of PET bottles, the proportion of transparent bottles prevailed; it ranged from 31% to 70%. Based on the results of the experiment, almost all PET bottle categories had a standard shape, except packaging for food products and household chemicals, in which 26–27% of PET bottles had a non-standard shape. The results about charactersitic of source-separated PET bottles are fundamental for goal-oriented design and implementation of collection, recycling technologies, secondary separation facilities, the economics of recycling intitatives and reverse vending machines for collecting materials.
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Ilyuschanka, A. Ph. "INVESTIGATION OF CHARACTERISTICS OF SPECIAL POWDERS AND MATERIALS PRODUCED BY MEANS OF SELECTIVE LASER MELTING." Proceedings of the National Academy of Sciences of Belarus, Physical-Technical Series 63, no. 2 (July 3, 2018): 150–60. http://dx.doi.org/10.29235/1561-8358-2018-63-2-150-160.
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The article presents the results of characterization of special powders of metal alloys and materials produced from these powders by selective laser melting (SLM), including comparative analysis of powders produced using VIGA technology. It is noted the importance of a complex study that includes not only a statistical evaluation of particle size distribution of the powders (preferably, by the method of laser diffraction), but also image analysis providing information on the particles’ shape influencing the powders’ flowability. It is shown that the size distribution and shape metrics for nickel refractory alloys and stainless steel powders obtained at the Powder Metallurgy Institute of the National Academy of Sciences of Belarus are at the level of the best foreign analogues. The influence of powder chemical composition on the mechanical properties of SLM samples is considered. The presence of oxygen and undesirable impurities, as a rule, decreases the strength and tensile strain. It is noted that SLM provides extremely wide opportunities for the formation of complex geometric structures with close to full density. Subsequent thermal or thermal and mechanical processing allows reduction of stresses arising during the SLM, densification of products (if necessary) and regulation of their structure and properties. The prospects of applying the backscattered electron diffraction (EBSD) for analysis of the material structure evolution during SLM and subsequent processing are shown. It is noted that products obtained by the SLM from the powders of special alloys exhibit mechanical properties at a level, and in some cases even exceeding the properties of these alloys produced by traditional and other additive technologies.
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Naumova, N. I., E. A. Burmistrov, and O. M. Burmistrova. "ABOUT FEATURES OF SETTING AND QUALITY OF MEALS OF BOARD FEED IN THE CONDITIONS OF CATERING «KOLTSOVO»." Innovations and Food Safety, no. 1 (March 28, 2019): 82–88. http://dx.doi.org/10.31677/2311-0651-2019-23-1-82-88.
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Onboard food is one of the components of normal flight tolerance. At enterprises for the production of on-board meals, ready meals and culinary products are produced, and their sale and consumption are organized. The purpose of the research was to study the features of manning and the quality of meals onboard food in the conditions of «Catering «Koltsovo» (the city of Yekaterinburg). As an object of research, a meat snack from the meals of the economy class food was used. In the course of physical and chemical tests, it has been established that the quality of raw materials (cheese of Dutch, boiled-smoked sausage and corn canned) used to make snacks, the content of table salt, moisture, foreign impurities, toxic metals (cadmium, lead) Regulated requirements. At the enterprise under study every technological stage is taken: storage, preparation, bundling of onboard food. On-board meals are prepared using high-tech equipment of Russian, Italian and German companies with observance of the temperature regime. Examination of the on-board dish revealed that the meat snack was placed in a disposable plate and packed in a polymer film with sealed ends from both sides. The label is marked on the package, the label contains the date of manufacture of the snack, the flight number of the aircraft and the shift. Organoleptic parameters of meat snacks, as well as sodium chloride content, average dish mass meet the requirements of the current regulatory documents. The onboard food prepared in conditions «Catering «Koltsovo», distinguish excellent taste qualities and attractive appearance.
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Gawdzińska, Katarzyna. "Application of Diffraction and X-Ray Microanalysis in Study of MMC Structure." Advanced Materials Research 690-693 (May 2013): 368–73. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.368.
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Quality of metal-matrix composite castings, similarly as quality of conventional metal castings is defined by the collection of data concerning chemical constitution, properties (e.g. strength) and structure of final products. During study aimed at determining these parameters, the priority is to maintain the highest possible repeatability and automation of measurement. In case of chemical constitution or mechanical properties analysis it is considerably easy to achieve thanks to application of appropriate research procedure. Analysis of structure of studied materials is however a much bigger problem. To improve it, different tools of digital image analysis are being used, but because of only slight differences (e.g. in color) between different elements of structure, conducting such analysis without performing additional study may result in obtaining false results. In such case, identification of an object is very important: unequivocal conclusion whether a given object is a reinforcement or maybe an impurity or an inclusion foreign matter, or is it a structure of improper, unintentional chemical constitution. It is particularly important concerning composites for which on the images obtained using both optical and scanning microscopy individual phases (reinforcement, matrix and impurities) are difficult to distinguish. In such case identification of particular phases is aimed at avoiding mistakes, for example while analyzing the quantity or uniformity of spacing of reinforcement phase in given space. X-ray diffraction may be a solution for this problem. An example of identification (quantitative and qualitative description) of reinforcement phase in suspension composites is presented further in the paper. The authors present also a chemical constitution of selected elements of structure of metal-matrix composites from ex-situ group.
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Vitjazeva, Olga, Igor Kozhuhov, and Larisa Naumova. "Ecological problems of the Russian coast of the south gulf of Finland." E3S Web of Conferences 244 (2021): 01001. http://dx.doi.org/10.1051/e3sconf/202124401001.
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The present work is an analytical review of the operating characteristics of the southern coast of the Gulf of Finland, which makes it possible to assess its state from the point of view of ecology. As a geographical and social object, this natural ecosystem can be reasonably included in the list of areas of potential ecological risk. This is due to active fishing activities and the development of sea cargo transshipment complexes in this area, taking into account the territorial advantages of local harbors. We believe that, with further accumulation of factual material, it will, with sufficient probability, determine the trends in the further development of this ecosystem. In the proposed work, the kinematics of coastal water flows near the southern coast was investigated as a factor contributing to the distribution of harmful impurities along the open part of the coast. Heavy metals and petroleum hydrocarbons were selected here as indicator pollutants. At the same time, the article does not consider in detail the issues of the influence of specific sources of pollution on the state of the ecosystem as a whole. The meaning of its writing, as planned, is to find a correlation between the pollution scheme of a given coast and the natural specifics of the local hydrological regime. When writing the article, the basis for the analytical study was the factual material that was once obtained by the forces of the Maritime Academy in the process of performing coastal field work at this facility. Further, the article contains the results of hydrochemical and geochemical testing of natural waters and modern bottom sediments of the Gulf, borrowed from domestic and foreign sources.
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Sharmin Sultana, Amisha Chowdhury, Tahmina Sultana, Khorshed Alam, and Ruhul A Khan. "Physicochemical and microbiological evaluation of surface water quality of aquaculture ponds Located in Savar, Dhaka, Bangladesh." GSC Advanced Research and Reviews 9, no. 2 (November 30, 2021): 138–46. http://dx.doi.org/10.30574/gscarr.2021.9.2.0284.
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Aquaculture is one of the most vital sectors in Bangladesh as it exhibits a major role in nutrition, livelihoods and foreign exchange incomes/earnings every year. However, due to chemical impurities, infectious diseases caused by microorganisms, heavy metal accumulation, and aquaculture in Bangladesh is gradually declining and posing serious health risks. In Savar, which is one of the major industrial zones in Bangladesh, all industrial sewage and wastes severely deteriorate the water quality of the ponds, rivers, lakes and various waterways that are involved in aquaculture/fish culture. Hence, to determine the water quality by assessing different physicochemical and microbiological parameters, water samples were collected from five selected ponds located in Atomic Energy Research Establishment premises, Savar, Dhaka and analyzed according to the standard procedures. The obtained values of temperature, pH, Salinity, TDS, TA, EC, TH, Chloride content, Free CO2, DO, Nitrate and Sulfate were compared with the recommended values of Bangladesh and WHO standard for suitable water quality. Most of the physicochemical parameters exceeded the Standard value. Total Viable Count, Total Coliform and Fecal Coliform Count were also found to be higher than the standard value of WHO indicating fecal contamination of the pond water. Some fish pathogens were also isolated from the ponds. Water quality index (WQI) was calculated for five sampling sites to determine the level of pollution. It was observed that the water quality of the all the ponds reached to critical point of pollution. It is therefore, a high time to take initiatives to save the ponds that are involved in aquaculture from further pollution. The results revealed that the pond waters of five different sites were excessively polluted and unsuitable for fish culture.