Chemical reaction

Research purpose: Using computational chemistry methods to study the mechanism of hydrogenation CO on the transition metal catalyst systems of Ni, Cu, Co, bimetallic catalysts NiCu, CoCu and catalytic systems bearing cluster on oxide carriers: MgO, Al2O3 and activated carbon (AC); compare and clarify the role of catalyst centers in single or bimetallic catalyst systems; clarifies the role of carriers (MgO, Al2O3 and AC) in the hydrogenation of CO.

27p thebadguys 08-06-2021 27 4   Download

Purpose: Using the density functional method (DFT) to find out the mechanism of CO2 hydrogenation reaction, the main product, by-products, the optimal reaction path, compare and evaluate the catalytic ability of the Ni5 cluster, Ni5/MgO, and Ni5/AC.

25p thebadguys 08-06-2021 13 3   Download

The objectives of the thesis: Extraction, chemical charaterization of glucomannan from the tubers of Amorphophallus Konjac K.Koch in Lam Dong, Vietnam; parameter optimization for glucomannan hydrolysis reaction to make different types of low molecular weight glucomannan by different methods.

27p capheviahe27 23-02-2021 16 4   Download

Fabbrication of electrocatalyst materials on the IrO2 basis for oxygen evolution reaction in proton exchange membrane water electrolyser PEMWE; applying to fabbricated proton exchange membrane water electrolyser PEMWE to produce hydrogen.

26p larachdumlanat129 20-01-2021 27 5   Download

The catalyst 7.5% NiO/TiO2 and seven samples of NiO/γ-Al2O3 with NiO content from 7.5% to 60% have been obtained and studied. Physico-chemical characteristics of the catalysts were determined by methods of Adsorption (BET), X-ray Diffraction (XRD), TemperatureProgrammed Reduction (TPR) and Hydrogen Pulse Titration. The catalytic properties of the obtained samples were investigated in the reaction of CO methanation at temperatures 180 – 220◦C and mole ratios hydrogen/carbon monoxide 25-100.

16p 12120609 01-06-2020 9 1   Download

This article draws a state of knowledge of the dissolution of uranium dioxide in nitric acid media. The chemistry of the reaction is first investigated, and two reactions appear as most suitable to describe the mechanism, leading to the formation of monoxide and dioxide nitrogen as reaction by-products, while the oxidation mechanism is shown to happen before solubilization.

13p christabelhuynh 30-05-2020 7 1   Download

This study aims at better understanding the chemical and physico-chemical phenomena of uranium dioxide dissolution reactions in nitric acid media in the Purex process, which separates the reusable materials and the final wastes of the spent nuclear fuels.

13p christabelhuynh 29-05-2020 14 1   Download

The quantum-chemical modeling mechanism of the [4+2]-cycloaddition reaction of 2,3 dimethylbuta-1,3-diene and methyl acrylate was conducted. Its qualitative aspects were analyzed at the molecular level by the program MOPAC2012 and semiempirical method RM1.

6p tocectocec 25-05-2020 8 2   Download

DFT calculations indicate that the decomposition reaction of nitroethyl benzoates in the presence of 1,3-dimethylimidazolium cation takes place much faster than in the case of the non-catalyzed process. Additionally, our calculations suggest one-step polar mechanism of title reactions.

8p tocectocec 25-05-2020 13 1   Download

A simple, efficient protocol for one pot synthesis of bis(indolyl)methanes from primary alcohols is investigated with N-bromosuccinimde as a catalyst under ultrasound irradiation.

7p tocectocec 26-05-2020 18 1   Download

This study synthesizes the use of chemicals to prevent one of common concrete durability problems, alkali-silica reaction (ASR), and can help researchers (i) identify widely used potential chemicals and evaluate these chemical solutions to prevent ASR with proper understanding of mechanisms, and (ii) to identify the research gaps in order to develop guidelines and implementation plan on the use of these chemicals for future research.

8p tohitohi 19-05-2020 23 1   Download

The two group I introns Nae.L1926 and Nmo.L2563, found at two different sites in nuclear LSU rRNA genes of Naegleria amoebo-flagellates, have been characterized in vitro. Their structural organization is related to that of the mobile Physarum intron Ppo.L1925 (PpLSU3) with ORFs extending the L1-loop of a typical group IC1 ribozyme. Nae.L1926, Nmo.L2563 and Ppo.L1925 RNAs all selfsplice in vitro, generating ligated exons and full-length intron circles as well as internal processed excised intron RNAs....

9p system191 01-06-2013 29 5   Download

Mer belongs to the Tyro 3 family of receptor tyrosine kinases (RTKs). Together with Axl and Rse, the three RTKs are believed to play important functional roles in the male gonads because gene knockout male mice lacking all of these receptors are infertile. In the present study, postnatal expression of Axl and Rse in mouse testes decreased during maturation while expression of Mer increased age-dependently during testicular development.

12p system191 01-06-2013 46 3   Download

Cannabinoid receptors and their endogenous ligands, the endocannabinoids, have been detected in several blood immune cells, including monocytes/macrophages, basophils and lymphocytes. However, their presence in dendritic cells, which play a key role in the initiation and development of the immune response, has never been investigated.

8p system191 01-06-2013 30 4   Download

Certain amino acids, like glutamine and leucine, induce an anabolic response in liver. They activate p70 ribosomal protein S6 kinase (p70S6K) and acetyl-CoA carboxylase (ACC) involved in protein and fatty acids synthesis, respectively. In contrast, the AMP-activated protein kinase (AMPK), which senses the energy state of the cell and becomes activated under metabolic stress, inactivates by phosphorylation key enzymes in biosynthetic pathways thereby conserving ATP.

9p system191 01-06-2013 50 5   Download

The goal of this study was to determine the effects of a putative specific cytosolic phospholipase A2 inhibitor, arachidonyl trifluoromethyl ketone (AACOCF3), on arachidonic acid (AA) release and lipid mediator biosynthesis by ionophore-stimulated human neutrophils. Initial studies indicated that AACOCF3 at concentrations 0–10 lM did not affect AA release from neutrophils. In contrast, AACOCF3 potently inhibited leukotriene B4 formation by ionophore-stimulated neutrophils (IC50  2.5 lM).

11p system191 01-06-2013 46 4   Download

2-Aminoethoxydiphenyl Borate (2-APB) has been extensively used recently as a membrane permeable modulator of inositol-1,4,5-trisphosphate-sensitive Ca2+ channels and store-operated Ca2+ entry. Here, we report that 2-APB is also an inhibitor of sarco/endoplasmic reticulum Ca2+ATPase (SERCA) Ca2+ pumps, and additionally increases ion leakage across the phospholipid bilayer. Therefore, we advise caution in the interpretation of results when used in Ca2+ signalling experiments.

10p system191 01-06-2013 41 4   Download

This review describes studies of particular enzymatically catalyzed reactions to investigate the possibility that catalysis is mediated by protein dynamics. That is, evolution has crafted the protein backbone of the enzyme to direct vibrations in such a fashion to speed reaction. The review presents the theoretical approach we have used to investigate this problem, but it is designed for the nonspecialist.

10p system191 01-06-2013 38 4   Download

This study addresses the interactions between the adaptor protein Shb and components involved in T cell signalling, including SLP-76, Gads, Vav and ZAP70. We show that both SLP-76 and ZAP70 co-immunoprecipitate with Shb in Jurkat T cells and that Shb and Vav co-immunoprecipitate when cotransfected in COS cells. We also demonstrate, utilizing fusion protein constructs, that SLP-76, Gads and Vav associate independently of each other to different domains or regions, of Shb.

10p system191 01-06-2013 37 5   Download

Human immunodeficiency virus type 1 protein R (HIV-1 Vpr) promotes nuclear entry of viral nucleic acids in nondividing cells, causes G2 cell cycle arrest and is involved in cellular differentiation and cell death. Vpr subcellular localization is as variable as its functions. It is known, that consistent with its role in nuclear transport, Vpr localizes to the nuclear envelope of human cells. Further, a reported ion channel activity of Vpr is clearly dependent on its localization in or at membranes.

6p system191 01-06-2013 38 4   Download