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2022 ◽  
Vol 372 ◽  
pp. 131117
Author(s):  
Claudia Mariana Castillo-Fraire ◽  
Sandrine Pottier ◽  
Arnaud Bondon ◽  
Erika Salas ◽  
Stéphane Bernillon ◽  
...  

Polymers ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 321
Author(s):  
Talkybek Jumadilov ◽  
Ruslan Kondaurov ◽  
Aldan Imangazy

The goal of the present work is a comparative study of the effectiveness of the application of intergel systems and molecularly imprinted polymers for the selective sorption and separation of neodymium and scandium ions. The following physico-chemical methods of analysis were used in this study: colorimetry and atomic-emission spectroscopy. The functional polymers of polyacrylic acid (hPAA) and poly-4-vinylpyridine (hP4VP) in the intergel system undergo significant changes in the initial sorption properties. The remote interaction of the polymers in the intergel system hPAA–hP4VP provides mutual activation of these macromolecules, with subsequent transfer into a highly ionized state. The maximum sorption of neodymium and scandium ions is observed at molar ratios of 83%hPAA:17%hP4VP and 50%hPAA:50%hP4VP. Molecularly imprinted polymers MIP(Nd) and MIP(Sc) show good results in the sorption of Nd and Sc ions. Based on both these types of these macromolecular structures, principally new sorption methods have been developed. The method based on the application of the intergel system is cheaper and easier in application, but there is some accompanying sorption (about 10%) of another metal from the model solution during selective sorption and separation. Another method, based on the application of molecularly imprinted polymers, is more expensive and the sorption properties are higher, with the simultaneous sorption of the accompanying metal from the model solution.


Author(s):  
L V S S Lohitasya Varun ◽  
Y. D. Dwivedi

The canard has been seen as an ominous aerodynamic object for ages this paper is to shed some more light on the effects of canard configuration on the aircraft’s wings. This flow-field analysis is thus being done using a turbulence model solution to take into the effects of a real-time environment where the vortices from the canard are captured more accurately. The analysis has been done meticulously and made to be as error-free as possible under the guidance of Dr. Yagya Dutta Dwivedi.


2021 ◽  
Vol specjalny (XXI) ◽  
pp. 205-215
Author(s):  
Olgierd Kucharski

The aim of the work was to present the factual competence of the State Labour Inspectorate and its analysis against the concept of „employment law”. This issue was presented on the basis of the classification of positions of the doctrine regarding „employment law” presented by B.M. Ćwiertniak. The review was carried out from the Act of 1981, which was a model solution for the „classical” labour law of the industrial era, to the current state based on the Act of 2007 and its amendments. The analysis has shown that this body is currently engaged in the control and supervision of „work” in its broadest sense. This is related to the fact that the material competence covers not only issues related to the employment relationship, but also the legality of employment, remuneration from the civil law relationship, social security obligations, bans on trade on Sundays and public holidays carried out regardless of the legal basis of employment. Therefore, from a formal point of view, the creation by the legislator of a possibly new branch of law - ‚employment law’ - would not require changes in the competences of the State Labour Inspectorate.


Membranes ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 45
Author(s):  
Ahmed Abarkan ◽  
Nabil Grimi ◽  
Hubert Métayer ◽  
Tarik Sqalli Houssaïni ◽  
Cécile Legallais

The hemodialysis technique, used worldwide for patients with chronic kidney disease, is considered as a treatment with a high economic and ecological impact, especially for water consumption. Getting ultrapure water for the preparation of the dialysate to clean patient’s blood from toxins leads to high volumes of salt-enriched water that directly goes to sewage. The aim of this work is to propose operating conditions for electrodialysis to allow the reuse of reverse osmosis (RO) rejects. We first performed a parametric study to evaluate the influence of different parameters, such as flow rates, initial concentration, and applied voltage on the demineralization rate (DR) and specific energy consumption (SPC) with a NaCl model solution. The optimal conditions for desalination (i.e., a potential of 12 V, and flow rate of 20 L·h−1) were then successfully applied to real samples collected from a dialysis center with total dissolved salts concentration of about 1.4 g/L (conductivity of 2.0 mS·cm−1). We demonstrated that the choice of adequate conductivity targets allowed meeting the physico-chemical requirements to obtain water re-usable for either rehabilitation swimming pool, manual or machine washing of instruments before sterilization or irrigation. Saving this water could contribute in the reduction of the environmental impact of hemodialysis.


Author(s):  
Илья Евгеньевич Глазов ◽  
Валентина Константиновна Крутько ◽  
Роман Алексеевич Власов ◽  
Ольга Николаевна Мусская ◽  
Людмила Викторовна Кульбицкая ◽  
...  

Синтезированы гибридные нанокомпозиты на основе гидроксиапатита и аутофибрина в форме фибринового сгустка либо цитратной плазмы путем осаждения при pH 9. «Мягкие» условия осаждения и быстрое выделение нанокомпозитов способствовали сохранению биополимерной матрицы аутофибрина. Дестабилизация дополнительной фазы аморфного фосфата кальция с образованием стехиометрического гидроксиапатита обусловлена влиянием макромолекул фибрина. Формирование кальцийдефицитного гидроксиапатита с x« 0,1 и Ca / P 1,65 происходило в среде цитратной плазмы, который после 800 °С превращался в смесь гидроксиапатит / 3 -трикальцийфосфат. Синтез композитов на основе биомиметического апатита осуществляли при добавлении 30 об.% модельного раствора Simulated Body Fluid (SBF). Влияние ионов Mg, CO~, входящих в состав SBF, способствовало стабилизации аморфного фосфата кальция и образованию карбонатзамещенного гидроксиапатита, устойчивого к термическим превращениям до 800°С. Совокупное влияние аутофибрина и ионов введенного SBF позволило управлять составом минеральной составляющей гибридных нанокомпозитов без разрушения биополимерной матрицы. Hybrid composites based on hydroxyapatite and autofibrin were synthesized by precipitation in a medium with pH = 9. Soft precipitation conditions and rapid isolation of the composite precipitates favored preservation of a biopolymer matrix of autofibrin. An effect of fibrin macromolecules contributed to destabilization of the amorphous calcium phosphate phase and formation of stoichiometric hydroxyapatite. The medium of the citrated plasma stimulated precipitation of calcium-deficient hydroxyapatite with x « 0,1 and the Ca / P ration of 1,65 which transformed into the mixture of hydroxyapatite / 3 -tricalcium phosphate at 800 °С. Biomimetic apatite composites were synthesized with an addition of 30 vol. % of a Simulated Body Fluid (SBF) model solution. The effect of Mg, CO~ ions of SBF promoted the stabilization of amorphous calcium phosphate and formation of carbonated hydroxyapatite that exhibited thermal stability up to 800 °С. The cummulative effect of autofibrin and ions of induced SBF provided controlling composition of the mineral part of hybrid nanocomposites without disruption of an autofibrin matrix.


Author(s):  
Татьяна Ивановна Правильникова ◽  
Ольга Александровна Голованова

В работе представлено исследование процессов осаждения минеральноорганических образований в модельном растворе плазмы крови в присутствии добавок альбумина, глицина, глюкозы, глутаминовой и молочной кислот. Методом рентгенофлуоресцентного анализа изучен фазовый состав образцов. Для измерения площади покрытия образца модифицированным фосфатом кальция были сделаны фотографии. На фотографиях были выделены области покрытия твердой фазой и с помощью программы ToupView произведен расчет степени покрытия образцов стали. Осаждение кристаллической фазы происходит на всех исследуемых образцах. Отличия заключаются в распределении кристаллов по поверхности пластины. Добавка альбумин ингибирует процесс осаждения гидроксилапатита на исследуемых образцах. Показано, что добавки глюкозы, глутаминовой и молочной кислот катализируют процесс осаждения гидроксилапатита на поверхности стального образца. В процентном соотношении, от общей площади фотографии, наибольшее количество осажденного порошка гидроксилапатита наблюдается у образцов с добавлением глюкозы. The paper presents a study of the processes of precipitation of mineral-organic formations in a model solution of blood plasma in the presence of additives of albumin, glycine, glucose, glutamic and lactic acids. The phase composition of the samples was studied by the X-ray diffraction analysis. Photos were taken to measure the surface area of the sample with modified calcium phosphate. The solid phase coating areas were highlighted in the photos and the degree of coating of steel samples was calculated using the ToupView software. The deposition of the crystal phase occurs on all the studied samples. The differences are in the distribution of crystals on the surface of the plate. The additive albumin inhibits the deposition of hydroxyapatite on the studied samples. It is shown, that additions of glucose, glutamic and lactic acids catalyze the process of hydroxylapatite deposition on the surface of a steel sample. As a percentage of the total area of the image, the largest amount of precipitated hydroxylapatite powder is observed in samples with the addition of glucose.


Author(s):  
Anna Rycaj-Pilipczuk

The subject of this study is to present the concept of a model solution for the public security system of monocentric and polycentric agglomeration. Taking into account the security conditions of a large urban agglomeration, one universal scheme of police organization has been adopted. Its func-tioning on the basis of specific forms and methods to some extent limits the autonomy of police chiefs in shaping safety in accordance with the specificity and internal social and organizational conditions of the agglomeration. Among the available research methods, the participatory observation method was used in particular. Nevertheless, the basic scientific method for obtaining empirical data was a diagnostic survey. Furthermore, the article presents the opinion of police officers on the transfer of solutions from the Warsaw agglomeration to other agglomerations in Poland. The author’s conceptual proposal of a model solution for the public safety system of a large urban agglomeration was presented.


2021 ◽  
Vol 12 (2) ◽  
pp. 166-196
Author(s):  
Andrea Pokludová

The main aim of this study is to present an analysis of the education conditions in the provincial capital of the Moravian Margraviate in the context of the national struggle for compulsory schooling between the German municipal government and Czech national activists at the turn of the 19th and 20th century. At the provincial level, the sharpest edges of Czech­ ­German conflict were to be blunted by the Moravian Compromise concluded in 1905, which included four provincial laws for the most troublesome areas, including the lex Perek. This study analyses and interprets the situation in Brno education through the lens of Czech emancipatory efforts from the mid-1870s to the passing of the lex Perek. Furthermore, it explains the situation after its passing, when the fight for the child was not coming to an end despite the concluded Czech­‑German Compromise – it rather escalated. This text thus deals with the real impact of one of the four provincial laws concluded within the Moravian Compromise, using the example of pre­‑war Brno. It is a probe into the issue at hand that uses the example of the provincial capital. The probe represents a practice that was far removed from the contemporary government’s presentation of the concluded compromise as a „model“ solution to the problematic Czech­‑German coexistence within the multinational monarchy.


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