45 research outputs found
Simulation of an electrolytic bath for electrodeposition of multilayer shielding coatings
In this the calculation work galvanic bath of Cu/(Ni+Cu) multilayer shielding coatings formation from an acetate electrolyte containing 0,03 mol/L of CuAc2, 0,3 mol/L of NiAc2 and 1,66 mol/L of acetic acid were made. According to the results of polarization studies values of coatings deposition pulse mode current density have been chosen and current efficiency of copper and nickel during deposition of Cu-Ni alloy has been determined. To ensure a constant formulation of the electrolyte it has been proposed to use insoluble anodes made
of stainless steel and continuous circulation of the electrolyte. The scheme of steams enabling the adjustment of the solution formulation with the use of an additional collecting vessel has been developed. The formulation of the correcting stream continuously fed into the collecting vessel has been calculated
Измерение удельной поверхности рыхлого осадка меди электрохимическими методами
In the work the surface area of the electrode with dispersed copper deposit obtained within 30 seconds was evaluated by techniques of chronopotentiometry (CPM) and impedance spectroscopy. In method CPM the electrode surface available for measurement depends on the value of the polarizing current. At high currents during the transition time there is a change of surface relief that can not determine the full surface of loose deposit. The electrochemical impedance method is devoid of this shortcoming since the measurements are carried out in indifferent electrolyte in the absence of current. The area measured by the impedance is tens of times higher than the value obtained by chronopotentiometry. It is found that from a solution containing sulfuric acid the deposits form with a high specific surface area. Based on these data it was concluded that the method of impedance spectroscopy can be used to measure in situ the surface area of the dispersed copper deposits.В работе проведена оценка площади поверхности электрода с дисперсным осадком меди, полученным в течение 30 секунд методами хронопотенциометрии (ХПМ) и импедансной спектроскопии. В методе ХПМ поверхность электрода, доступная для измерения, зависит от
величины поляризующего тока. При больших токах в течение переходного времени происходит изменение рельефа поверхности, что не позволяет определить полную поверхность рыхлого осадка. Метод электрохимического импеданса лишен этого недостатка, так как измерения проводятся в индифферентном электролите в отсутствие тока. Площадь, измеренная методом импеданса, в десятки раз превышает значения, полученные методом хронопотенциометрии. Установлено, что из раствора, содержащего серную кислоту, формируются осадки с высокой удельной поверхностью. На основании полученных данных сделан вывод, что метод импедансной спектроскопии может быть использован для измерения in situ площади поверхности дисперсных осадков меди
Phlebotomine sand fly survey in the focus of leishmaniasis in Madrid, Spain (2012-2014): seasonal dynamics, Leishmania infantum infection rates and blood meal preferences
BACKGROUND: An unusual increase of human leishmaniasis cases due to Leishmania infantum is occurring in an urban area of southwestern Madrid, Spain, since 2010. Entomological surveys have shown that Phlebotomus perniciosus is the only potential vector. Direct xenodiagnosis in hares (Lepus granatensis) and rabbits (Oryctolagus cuniculus) collected in the focus area proved that they can transmit parasites to colonized P. perniciosus. Isolates were characterized as L. infantum. The aim of the present work was to conduct a comprehensive study of sand flies in the outbreak area, with special emphasis on P. perniciosus. METHODS: Entomological surveys were done from June to October 2012-2014 in 4 stations located close to the affected area. Twenty sticky traps (ST) and two CDC light traps (LT) were monthly placed during two consecutive days in every station. LT were replaced every morning. Sand fly infection rates were determined by dissecting females collected with LT. Molecular procedures applied to study blood meal preferences and to detect L. infantum were performed for a better understanding of the epidemiology of the outbreak. RESULTS: A total of 45,127 specimens belonging to 4 sand fly species were collected: P. perniciosus (75.34%), Sergentomyia minuta (24.65%), Phlebotomus sergenti (0.005%) and Phlebotomus papatasi (0.005%). No Phlebotomus ariasi were captured. From 3203 P. perniciosus female dissected, 117 were infected with flagellates (3.7%). Furthermore, 13.31% and 7.78% of blood-fed and unfed female sand flies, respectively, were found infected with L. infantum by PCR. The highest rates of infected P. perniciosus were detected at the end of the transmission periods. Regarding to blood meal preferences, hares and rabbits were preferred, although human, cat and dog blood were also found. CONCLUSIONS: This entomological study highlights the exceptional nature of the Leishmania outbreak occurring in southwestern Madrid, Spain. It is confirmed that P. perniciosus is the only vector in the affected area, with high densities and infection rates. Rabbits and hares were the main blood meal sources of this species. These results reinforce the need for an extensive and permanent surveillance in this region, and others of similar characteristics, in order to control the vector and regulate the populations of wild reservoirs.This study was partially sponsored and funded by: Dirección General de Salud Pública, Consejería de Sanidad, Comunidad de Madrid; Colegio de Veterinarios de Madrid; Colegio de Biólogos de Madrid and EU grant
FP7-261504 EDENext (http://www.edenext.eu).S
Measurement of the specific surface area of loose copper deposit by electrochemical methods
In the work the surface area of the electrode with dispersed copper deposit obtained within 30 seconds was evaluated by techniques of chronopotentiometry (CPM) and impedance spectroscopy. In method CPM the electrode surface available for measurement depends on the value of the polarizing current. At high currents during the transition time there is a change of surface relief that can not determine the full surface of loose deposit. The electrochemical impedance method is devoid of this shortcoming since the measurements are carried out in indifferent electrolyte in the absence of current. The area measured by the impedance is tens of times higher than the value obtained by chronopotentiometry. It is found that from a solution containing sulfuric acid the deposits form with a high specific surface area. Based on these data it was concluded that the method of impedance spectroscopy can be used to measure in situ the surface area of the dispersed copper deposits
PRODUCTION OF MELTED BUTTER WITH INCREASED STORAGE STABILITY
The paper presents data on melted butter preservation research. It has been conducted analysis of the components applied and their positive impact on the butter storage. To last belong sodium chloride staying the formation of free fatty acids and also additionally contributable lactatecontaining additive. Laboratory studies were carried out in a certain way. A half of each batch of butter were remelted in two versions with the addition of sodium chloride up to 4 % by weight of the butter to precipitate proteins and without the addition of the salt. Food additive with the properties of animal origin products shelf life increase were supplemented into the melted butter. The rest manufacturing operations were performed by the traditional method of melted butter production. It was evaluated the organoleptic characteristics and investigated fat phase acidity and fat peroxide number in the samples of melted butter with a month interval. Also were determinated the transparency of test samples. All test samples in molten state were transparent, they didn't contain suspended particles. Results of the score were summarized and on the base of the total assessment were determinated quality of the product. The carried out researches of samples of melted butter have shown the full conformance with requirements of GOST R 52971 on physicochemical parameters: the weight fraction of fat – 99 %, the weight fraction of moisture – 1 %. It was established that in the samples without food additive maximum values of acid number were received in a month of storage; and in the samples with additive - in 3 months of storage. It was determinated that in samples of butter rented without salting peroxide number increases more intensively than in other test samples. It has been determined increased storage stability of melted butter with salt and food additive
COTTAGE CHEESE PRODUCTS WITH INGREDIENTS OF PLANT ORIGIN
Proposed the use of feijoa as a filler for cheese products. Distinctive at-sign feijoa is a high content of watersoluble compounds in the fruits of iodine. According to their content feijoa can match with seafood, no plant does not accumulate a large number of iodine compounds (about 0.2 1 mg per 100 g of product). Feijoa is very useful for people living in iodine deficiency regions, as well as for preventers of thyroid diseases. The rind of the fruit is rich in antioxidants. The technology of GUT-goad product feijoa. Feature of the technology is that the finished cheese is made in the form of a mixture of filler pureed fruit pulp and sugar in a ratio of 1: 1, and the powder dry skin. Objects of research a filler in the form of syrup (pineapple guava pulp and sugar) and the rind of the fruit in the form of crushed dry cottage cheese. Compatible with cream cheese filling sensory determined by the following indicators appearance, consistency, color, smell, taste. Syrup dosage ranged from 1 to 10%, dry filler from 0.5 to 3.5%. A mixture of fillers were added to the finished curd product in the ratio of syrup fairies feijoa and dry powder peel 8: 1.5. Technological process of cottage cheese product is different from the traditional operations of preparation of fillers and incorporation in the finished cheese. Determined the antioxidant activity syrup feijoa 1,963 mg / dm3 . It was found that the cheese product is rich in antioxidants, iodine, which helps to eliminate free radicals from the body and strengthen health care. Herbal additive allows to obtain a product with a new taste characteristics. The shelf life of cottage cheese products 5 days
MELTED BUTTER TECHNOLOGY DEVELOPMENT
Summary. Melted butter is made from dairy butter by rendering the fat phase. It has specific taste and aroma, high-calorie content and good assimilability. Defects of butter which appeared during the storage causes by the development of microbiological processes or by the chemical oxidation. On the development of these processes influence quality and composition of fresh butter, its physical structure, content of the increased amount of gas phase and content of heavy metals, storage conditions. Microbiological spoilage of butter occurs generally due to damage of plasma which is good environment for the development of microorganisms. Defects of microbiological origin include: unclean, sour, moldy, yeasty, cheesy, bitter taste. Defects of test and smell chemical origin are formed due to hydrolytic digestion of lipids. It's prevailed at long storage of butter in the conditions of freezing temperatures. It's picked out the following main processes of spoiling: souring, acidifying and sallowness. Often these processes take place simultaneously.It has been investigated melted butter with lactated additive. The latter improves the microbiological and toxicological safety, prolongs the storage condition of the products. Technological efficiency of the additives is achieved by a multilayer products formation from the inactive bound water, preventing microorganisms growth and by the barrier layer with lactate inhibiting hydrolytic reactions. Oil samples were obtained with the batch-type butter maker application, then they were melted and after that lactated additive were supplemented. It has been studied organoleptic and physico-chemical indices of the melted butter samples. The fatty-acid composition of melted butter were studied. Comparative analysis of fatty-acid composition of cow's milk fat and produced melted butter has shown their similarity. Also in the last sample there is increased weight fraction of linoleic and linolenic acids. The obtained experimental data for melted butter allow to conclude about its high quality
ACTIVITY OF TUBERCULOSIS WHEN CALCIFICATION IS DETECTED IN THE CHEST LYMPH NODES AND LUNGS OF CHILDREN
Introduction of new examination techniques to tuberculosis control in children resulted in the increase of Group IIIA of the dispensary follow-up.Goal: to define criteria of tuberculosis disease activity when calcification is detected in the chest lymph nodes of children. Follow-up included children in the age from 1,5 months to 17 years old examined in TB dispensaries of Yekaterinburg and Tyumen. 1A Subgroup (n = 145) of children demonstrated further increase and/or induration of calcification and in 27 children calcification did not change (1B Subgroup). In Subgroup 2A1 – 184 patients had changes in the X-ray manifestations, 31 persons demonstrated calcification in chest lymph nodes (Subgroup 2A2 ), 13 persons demonstrated no changes in X-ray manifestations which was considered as metatuberculous (fibrous) changes (2B Group). Two criteria witnessing of the absence of active tuberculosis disease were identified: infection with tuberculosis more than 4 years ago and stable level of α2-fraction in the protein profile. These indicators can serve as true criteria when no clinical signs of intoxication are observed and calcification is detected by X-ray, while the child has not been exposed to tuberculosis