Synthesis and Properties of the Copper Composite Membranes

Composite catalysts based on track-etched membranes (TeMs) and metal nanoparticles (NPs) or nanotubes (NTs) deposited by different approaches have drawn a special attention because of attractive catalytic properties coupled with large catalytically active surface, high mechanical strength and efficient flexibility, which allows them to be successfully used for several reaction cycles without additional manipulation of purification and activation

Impact of Testing Temperature on the Structure and Catalytic Properties of Au Nanotubes Composites

In the paper, the catalytic activity of composites based on gold nanotubes and ion track membranes was studied using bench reaction of the p-nitrophenol (4-NP) reduction in the temperature range of 25-40 °C. The efficiency of the prepared catalysts was estimated on the rate constant of the reaction and by conversion degree of 4-NP to p-aminophenol (4-AP). The comprehensive evaluation of the structure was performed by X-ray diffraction and scanning electron microscopy. A decreasing of the composites activity was observed when the reaction were carried out at the temperature over 35 °C, due to an increased average crystallite size from 7.31±1.07 to 10.35±3.7 nm (after 1st run). In temperature range of 25-35 °C the efficiency of the composite catalyst was unchanged in 3 runs and decreases by 24-32 % after the 5th run. At the high temperature of 40 °C after the 5th run the composite become completely  catalytically inert. Copyright © 2018 BCREC Group. All rights reserved Received: 23rd January 2018; Revised: 19th March 2018; Accepted: 19th March 2018 How to Cite: Mashentseva, A.A., Zdorovets, M.V., Borgekov, D.B. (2018). Impact of Testing Temperature on the Structure and Catalytic Properties of Au Nanotubes Composites. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 405-411 (doi:10.9767/bcrec.13.3.2127.405-411) Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2127.405-41

COMPOSITE-TRACK ETCHED MEMBRANES FOR ENVIRONMENTAL APPLICATIONS

The photocatalytic removal of various classes of organic and inorganic pollutants is one of the most widely used methods due to its high efficiency, low cost and simplicity. The current research in this area is aimed at developing new technologies for producing high-performance and low-cost catalysts. Various types of composite materials have attracted much research attention in the field of photocatalysis owing to their advantages, such as their design flexibility, improved physical and chemical properties and stability

DETERMINATION OF OPTIMAL SYNTHESIS CONDITIONS OF THE CU@PET COMPOSITES USING TAGUCHI ROBUST EXPERIMENT DESIGN

In this task the Taguchi robust design was applied to optimize experimental parameters as well as to determine the optimal conditions for the electroless copper plating. Taguchi robust planning is widely used in the production and study of various technological processes and scientific research, including synthesis of nanomaterials and the study of their properties..

FABRICATION OF THE AG/DMAEMA@PET COMPOSITES FOR EFFICIENCY REMOVAL OF AS(III) IONS

Reversible addition-fragmentation chain transfer (RAFT) polymerization is considered as the most promising synthetic route to prepare well-controlled structures with enhanced performance in specialized applications. Polymers synthesized by controlled free-radical polymerization (CRP) techniques process well-defined molecular architectures and are used in many applications such as drug-delivery, special sensing materials, molecular imprinting, polymer-protein conjugates, development of cylindrical, spherical, hyper-branched polymers, pH or temperature responding smart polymers, etc

Allobetulin and Its Derivatives: Synthesis and Biological Activity

This review covers the chemistry of allobetulin analogs, including their formation by rearrangement from betulin derivatives, their further derivatisation, their fusion with heterocyclic rings, and any further rearrangements of allobetulin compounds including ring opening, ring contraction and ring expansion reactions. In the last part, the most important biological activities of allobetulin derivatives are listed. One hundred and fifteen references are cited and the relevant literature is covered, starting in 1922 up to the end of 2010

APPLICATION OF BIOGENIC ZINC OXIDE NANOPARTICLES IN THE DEGRADATION OF ORGANIC DYES

Heterogeneous photocatalysis is one of the most popular methods among the variety of different technologies to purify environmental pollutant. The dye Rhodamine B and Alizarin Yellow R are used in many industrial applications and have side effect, when significant amount of the dye is washed off with the wastewater of production during the process, falling into surface reservoirs and destroying the ecosystem

Окисление пероксидом водорода как эффективный способ повышения реакционной способности ПЭТФ трековых мембран в реакциях фотоинициированной полимеризации

В данной статье представлены результаты функционализации трековых мембран на основе полиэтилентерефталата (ПЭТФ ТМ) путем окисления с использованием современных методов на основе перекиси водорода и последующей УФ-инициированной прививочной полимеризации акриловой кислоты с целью повышения химической активности поверхности и расширения практического применения. Среди современных окислительных систем, система H2O2 под УФ-облучением была выбрана для максимально эффективного получения концевых СООН-групп на поверхности мембраны. УФ-инициированная полимеризация была проведена одновременно с двух сторон мембраны, что привело к формированию слоя полиакриловой кислоты, как на поверхности, так и внутри пор ПЭТФ ТМ. Эффект влияния кислород-насыщенной поверхности на адсорбционную способность бензофенона (инициатора прививочной полимеризации) и на эффективность прививочной полимеризации был изучен методом ЭПР спектроскопии. Полученные образцы были изучены методами УФ, ИК-, РФЭ-спектроскопий, а также сканирующей электронной микроскопии (СЭМ)

The Study of the Structure-Activity Relationship For a Cinnamic Acid Derivatives

Для изучения взаимосвязи «структура-активность» исследован ряд производных коричной кислоты. С использованием современных методов проведен скрининг антирадикальной активности, для всех соединений рассчитаны эффективные коэффициенты ингибирования. Показано, что введение гидроксильного заместителя в молекулу коричной кислоты значительно повышает восстановительные свойства последней. Наличие заместителя в м-положении несколько снижает значение эффективного коэффициента ингибирования IC50. Наиболее эффективными антиоксидантами являются орто-дигидроксизамещенная кофейная и феруловая кислоты; так, по способности ингибировать DPPH-радикал кофейная кислота превосходит коричную в 3,2 раза, бутилированный гидроксианизол (BHA) - в 1,6 раза. Методами квантовой химии произведен расчет некоторых физико-химических параметров, определяющих восстановительные свойства молекул - потенциал ионизации (IP), энергию сродства к электрону и энтальпию диссоциации ОН-связи. Коричная кислота, не имеющая в структуре молекулы гидроксильных групп, имеет самый высокий IP, м-положение ОН- группы в гидроксикоричной кислоте, немного понижает восстановительную способность по сравнению с о-замещением. Минимальное значение IP хлорогеновой и аскорбиновой кислот подтверждает их высокий антиоксидантный статус. Проведен корреляционный анализ экспериментальных и теоретических данных (коэффициентом достоверности R2=0,5265).The structure-radical scavenging activity relationship for some cinnamic acid derivatives was investigated. The radical scavenging activity (RSA) using modern assays were studied and the effective coefficients for all compounds were calculated. It was founded that hydroxyl group presence is increasing the reduction properties of the cinnamic acid, and the m- substitute presence is decreasing the IC50 value. The most effective antioxidants are o-dihydroxy substituted caffeic and ferulic acids; it could exceed the DPPH RSA of the cinnamic acid in 3.2times, BHA - in 1.6 times. Using quantum-chemistry program some physic-chemical properties like as ionization potential (IP), electron affinity energy and O-H bond dissociation enthalpy, which can be used as an antioxidant activity descriptors were calculated. The not having any O-H group in structure cinnamic acid has the highest value of IP, m-substitution of O-H group in hydroxyl cinnamic acid is decreasing the reduction ability as compared to o-substitution. The highest antioxidant potential of the chlorogenic and ascorbic acids is confirmed by the least IP values. The correlation analysis foe the experimental and theoretical data was searched with the confidence factor value R2=0.526

Synthesis and Properties of the Copper Composite Membranes

Composite catalysts based on track-etched membranes (TeMs) and metal nanoparticles (NPs) or nanotubes (NTs) deposited by different approaches have drawn a special attention because of attractive catalytic properties coupled with large catalytically active surface, high mechanical strength and efficient flexibility, which allows them to be successfully used for several reaction cycles without additional manipulation of purification and activation