Добірка наукової літератури з теми "Foreign impurities"

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.

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.

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.

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.

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”.

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.

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.

(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.

Дисертація на здобуття наукового ступеню доктора технічних наук за спеціальністю 05.18.06 − технологія жирів, ефірних масел і парфумерно-косметичних продуктів – Національний технічний університет "Харківський політехнічний інститут" Міністерства освіти і науки України, Харків, 2018 р. Дисертаційну роботу присвячено науковому обґрунтуванню застосування системного комплексного підходу щодо створення сучасних схем технохімічного контролю сировини і готової продукції олійножирових виробництв з використанням виключно інструментальних методів аналізу: газорідинної хроматографії, високоефективної рідинної хроматографії, газової хромато-масспектроскопії, зонального капілярного електрофорезу та ін. На основі узагальнення теоретичних і експериментальних даних розроблено схему забруднення олійного насіння, соняшникової олії та олієжировмісних продуктів природними та антропогенними екотоксикантами: пестицидами, поліхлорованими біфенілами, поліароматичними вуглеводнями, фталатами, сторонніми домішками органічного і неорганічного походження, харчовими добавками. Удосконалено стандартизований метод визначення воскоподібних речовин. Експериментально досліджено розподіл пестицидів різних класів у насінні соняшнику і продуктах його переробки. Розроблено науково обґрунтовані способи визначення пестицидів, в т.ч. за умови їх сумісної присутності. Гармонізовано з міжнародними вимогами спосіб визначення поліароматичних вуглеводнів (ПАВ) і встановлено, що вміст бенз(а)пірену є технологічним маркером по відношенню до суми ПАВ. Розроблено пріоритетний спосіб визначення фталатів, що мігрують з ПЕТ-упаковки у рослинні олії та жировмісні продукти. Теоретично та експериментально обгрунтовано необхідність застосування методів визначення жирнокислотного, ацилгліцерольного (в т.ч. індивідуального) та складу стеролової фракції для ідентифікації олій та жирів, зокрема для виявлення сторонніх домішок мінерального (мінеральних олив) та органічного (нехарчового курячого жиру) походження, тобто для цілей фальсифікації. Створено наукове та методологічне підґрунтя щодо створення національного стандарту щодо контролювання вмісту консервантів у жировмісних продуктах. Розроблено практичні рекомендації щодо удосконалення схем технохімконтролю сировини і готової продукції у виробництві соняшникової олії, в т.ч. фасованої в полімерну тару, маргаринової продукції, майонезу та салатних соусів, купажованих олій.
Thesis for the Doctor's of Engineering by specialty 05.18.06 − technology of fats, essential oils and perfumery and cosmetic products. − National Technical University "Kharkiv Polytechnic Institute" of the Ministry of Education and Science of Ukraine, Kharkiv, 2018. The thesis is devoted to the scientific substantiation of the application of the system complex approach to the creation of modern schemes of techno-chemical control of raw materials and finished products of fat-and-oil production with the use of exclusively instrumental methods of analysis: gas-liquid chromatography, high-performance liquid chromatography, gas chromatography, zonal capillary electrophoresis, etc. It has been developed the scheme on the basis of theoretical and experimental data generalization of oilseed, sunflower oil and oily products contamination by natural and anthropogenic ecotoxicants, namely pesticides, polychlorinated biphenyls, polyaromatic hydrocarbons, phthalates, foreign impurities of organic and inorganic origin, and food additives. The standardized method of determining wax-like substances has been improved. The distribution of pesticides of various classes in sunflower seed and products of its processing has been experimentally investigated. Scientifically grounded methods of pesticide determination have been developed including their simultaneous presence. A priority method for determination of migrating phthalates from PET packaging in vegetable oils and fat-containing products has been developed. The necessity of using methods for determining the fatty acid, acylglycerol (including individual) and composition of the sterol fraction for the identification of oils and fats, in particular for the foreign impurities detection of mineral (mineral oils) and organic (nonfood chicken fat) origin, i.e. for goals of falsification, has been grounded scientifically and theoretically. A scientific and methodological basis for establishing a national standard for controlling the content of preservatives in fatty products has been created. Practical recommendations for improving the schemes of technochemical control of raw materials and finished products in the sunflower oil production, including packed in plastic containers, margarine products, mayonnaise, salad dressings and blended oils have been developed.

Дисертація на здобуття наукового ступеню доктора технічних наук за спеціальністю 05.18.06 − технологія жирів, ефірних масел і парфумерно-косметичних продуктів – Національний технічний університет "Харківський політехнічний інститут" Міністерства освіти і науки України, Харків, 2018 р. Дисертаційну роботу присвячено науковому обґрунтуванню застосування системного комплексного підходу щодо створення сучасних схем технохімічного контролю сировини і готової продукції олійножирових виробництв з використанням виключно інструментальних методів аналізу: газорідинної хроматографії, високоефективної рідинної хроматографії, газової хромато-масспектроскопії, зонального капілярного електрофорезу та ін. На основі узагальнення теоретичних і експериментальних даних розроблено схему забруднення олійного насіння, соняшникової олії та олієжировмісних продуктів природними та антропогенними екотоксикантами: пестицидами, поліхлорованими біфенілами, поліароматичними вуглеводнями, фталатами, сторонніми домішками органічного і неорганічного походження, харчовими добавками. Удосконалено стандартизований метод визначення воскоподібних речовин. Експериментально досліджено розподіл пестицидів різних класів у насінні соняшнику і продуктах його переробки. Розроблено науково обґрунтовані способи визначення пестицидів, в т.ч. за умови їх сумісної присутності. Гармонізовано з міжнародними вимогами спосіб визначення поліароматичних вуглеводнів (ПАВ) і встановлено, що вміст бенз(а)пірену є технологічним маркером по відношенню до суми ПАВ. Розроблено пріоритетний спосіб визначення фталатів, що мігрують з ПЕТ-упаковки у рослинні олії та жировмісні продукти. Теоретично та експериментально обгрунтовано необхідність застосування методів визначення жирнокислотного, ацилгліцерольного (в т.ч. індивідуального) та складу стеролової фракції для ідентифікації олій та жирів, зокрема для виявлення сторонніх домішок мінерального (мінеральних олив) та органічного (нехарчового курячого жиру) походження, тобто для цілей фальсифікації. Створено наукове та методологічне підґрунтя щодо створення національного стандарту щодо контролювання вмісту консервантів у жировмісних продуктах. Розроблено практичні рекомендації щодо удосконалення схем технохімконтролю сировини і готової продукції у виробництві соняшникової олії, в т.ч. фасованої в полімерну тару, маргаринової продукції, майонезу та салатних соусів, купажованих олій.
Thesis for the Doctor's of Engineering by specialty 05.18.06 − technology of fats, essential oils and perfumery and cosmetic products. − National Technical University "Kharkiv Polytechnic Institute" of the Ministry of Education and Science of Ukraine, Kharkiv, 2018. The thesis is devoted to the scientific substantiation of the application of the system complex approach to the creation of modern schemes of techno-chemical control of raw materials and finished products of fat-and-oil production with the use of exclusively instrumental methods of analysis: gas-liquid chromatography, high-performance liquid chromatography, gas chromatography, zonal capillary electrophoresis, etc. It has been developed the scheme on the basis of theoretical and experimental data generalization of oilseed, sunflower oil and oily products contamination by natural and anthropogenic ecotoxicants, namely pesticides, polychlorinated biphenyls, polyaromatic hydrocarbons, phthalates, foreign impurities of organic and inorganic origin, and food additives. The standardized method of determining wax-like substances has been improved. The distribution of pesticides of various classes in sunflower seed and products of its processing has been experimentally investigated. Scientifically grounded methods of pesticide determination have been developed including their simultaneous presence. A priority method for determination of migrating phthalates from PET packaging in vegetable oils and fat-containing products has been developed. The necessity of using methods for determining the fatty acid, acylglycerol (including individual) and composition of the sterol fraction for the identification of oils and fats, in particular for the foreign impurities detection of mineral (mineral oils) and organic (nonfood chicken fat) origin, i.e. for goals of falsification, has been grounded scientifically and theoretically. A scientific and methodological basis for establishing a national standard for controlling the content of preservatives in fatty products has been created. Practical recommendations for improving the schemes of technochemical control of raw materials and finished products in the sunflower oil production, including packed in plastic containers, margarine products, mayonnaise, salad dressings and blended oils have been developed.

This chapter provides an overview of the broader context within which debates regarding graves, funeral architecture and ziyāra have taken place. The early Islamic interdictions against certain funerary structures and grave-related rites did not arise in a vacuum. Therefore, the chapter contextualises these debates and the gap that began to emerge between the traditionalists’ (Ahl al-hadith) vision of ideal Islam and the reality of popular Islam. The chapter also offers a detailed focus on the teachings of Ibn Taymiyya, as it was his narrative of Islamic history and the ideal Islamic community that inspired later Sunni reformists, among them the Salafis, who sought to defend Islamic identity against the incursion of foreign influences and impurities, be they elements of Christianity, Judaism, syncretism or modernity.

Gas turbine parts used in today’s aircraft and power generation applications are experiencing one of the most challenging mechanical and thermal operating environments. While there is a compelling need for more realistic life predictions of turbine components for safer operation, it is important from contractual service costing perspective as well. Therefore, design engineers should strike a balance between component safety and life cycle cost by carefully incorporating design conservatism in life estimation processes and tools used in the design of these components. This paper outlines some of the unique challenges encountered in life predictions of gas turbine components and a brief review on the current methods and trends. The predominant failure modes discussed are: airfoil corrosion fatigue due to Foreign Object Damage (FoD) and subsequent erosion, cyclic failure modes like high cycle fatigue (HCF), fretting fatigue and low cycle fatigue (LCF), high temperature failure mechanisms like creep, oxidation, hot corrosion and spallation. Also, the challenges in the prediction of crack propagation life due to fatigue initiated cracks and defects due to material impurities are discussed. The interaction effects between creep and fatigue and those between LCF and HCF are also outlined in this paper.

This paper investigates and justifies the use of a minimum necessary cleaning force ratio or cleaning factor for steam blows. Steam line blowing is an operational cleaning method used to clean steam piping and reheaters prior to turbine powering for steam power plants. The steam blows remove weld bead deposits, slag, debris, surface scale, and other foreign materials which could be carried into the steam turbines and damage the turbine blades during normal plant operation. Piping is blown, bypassing the turbine, with sufficient boiler pressure to ensure the dynamic pressure throughout the piping is greater than would be experienced during all plant operating conditions. By providing flow rates corresponding to the maximum service condition for any given section of piping, there will be sufficient kinetic energy to ensure complete removal of any impurities from the pipe. Historically, the required steam blow pressures are calculated to achieve a cleaning force ratio of 1.2. Cleaning Force Ratio (CFR) or Cleaning Factor (CF) is an industry-accepted factor that quantifies the ratio of required dynamic pressure for cleaning to maximum dynamic pressure experienced during system operation. For CFRs, the turbine vendors tend to have guidelines or ranges rather than definitive acceptance criteria. It is usually left up to the commissioning engineer, the Project Startup Manager and Owner to determine what is necessary for final acceptance. It is desirable to reduce the required minimum blowout pressure and flow rate to facilitate plant startup. By reducing the required minimum blowout pressure and flow rate, permanent plant equipment and temporary steam blow piping wear can be reduced and over cleaning avoided. Further, time between steam blows can be reduced. This paper examines the CFR guidelines for various turbine vendors and justifies reducing the CFR from 1.2 to 1.0. Advantages of the use of a minimum necessary CFR include reduced required steam blow pressures which result in safer steam blows, and less expensive temporary steam blow piping. Use of a minimum necessary CFR will still maintain the effectiveness of the steam blow.