The intrinsic effect of co-feeding water on the formation of active/deactivating species in the methanol-to-hydrocarbons reaction on ZSM-5 zeolite

2021 ◽  
Author(s):  
José Valecillos ◽  
Gorka Elordi ◽  
Andrés T. Aguayo ◽  
Pedro Castaño
Keyword(s):  
Reaction Intermediates ◽  
Slowing Down ◽  
Methanol To Hydrocarbons ◽  
Zeolite P ◽  
Intrinsic Effect

Water is formed and added in the conversion of methanol to hydrocarbons, slowing down both the reaction and deactivation rates. The retained species that are reaction intermediates and coke precursors are swept/desorbed, particularly those on silanol sites.

Mechanistic insights of selective syngas conversion over Zn grafted on ZSM-5 zeolite

2020 ◽  
Vol 10 (24) ◽  
pp. 8173-8181
Author(s):  
Wei Chen ◽  
Dinesh Acharya ◽  
Zhiqiang Liu ◽  
Xianfeng Yi ◽  
Yao Xiao ◽  
...  
Keyword(s):  
Transition States ◽  
Reaction Pathways ◽  
Reaction Intermediates ◽  
Syngas Conversion ◽  
Zeolite P

On the basis of syngas conversion mechanism over Zn2+-ion exchanged ZSM-5 zeolite, the reaction pathways, reaction intermediates and transition states were determined clearly.

Analyzing reactions of single mechanoenzyme molecules by light microscopy

1992 ◽  
Vol 50 (1) ◽  
pp. 426-427
Author(s):  
Jeff Gelles
Keyword(s):  
Image Processing ◽  
Reaction Mechanisms ◽  
Transient State ◽  
Nanometer Scale ◽  
Reaction Intermediates ◽  
Enzyme Molecule ◽  
Directed Movement ◽  
Enzyme Molecules ◽  
Individual Enzyme ◽  
Single Reaction

Mechanoenzymes are enzymes which use a chemical reaction to power directed movement along biological polymer. Such enzymes include the cytoskeletal motors (e.g., myosins, dyneins, and kinesins) as well as nucleic acid polymerases and helicases. A single catalytic turnover of a mechanoenzyme moves the enzyme molecule along the polymer a distance on the order of 10−9 m We have developed light microscope and digital image processing methods to detect and measure nanometer-scale motions driven by single mechanoenzyme molecules. These techniques enable one to monitor the occurrence of single reaction steps and to measure the lifetimes of reaction intermediates in individual enzyme molecules. This information can be used to elucidate reaction mechanisms and determine microscopic rate constants. Such an approach circumvents difficulties encountered in the use of traditional transient-state kinetics techniques to examine mechanoenzyme reaction mechanisms.

Pengaruh Inflasi, BI Rate, NPF, dan BOPO terhadap Profitabilitas Bank Umum Syariah di Indonesia

2018 ◽  
Vol 6 (1) ◽  
pp. 133-153
Author(s):  
Toufan Aldian Syah
Keyword(s):  
Banking Industry ◽  
External Factors ◽  
Coefficient Of Determination ◽  
Muslim Country ◽  
Internal Factors ◽  
Slowing Down ◽  
The World ◽  
Negative Effect ◽  
Test Correlation ◽  
The Ideal

Banking industry has a very important role in economic development in a country. Indonesia, which is the largest Muslim country in the world, certainly has the prospect of the development of Sharia Banking Industry is very good in the future. However, the development of Sharia Bank has been slowing down in recent years and the profitability of sharia comercial banking is still below the ideal value. This study aims to determine the internal factors and external factors that affect the profitability of Sharia Bank in the year of January 2012 until August 2017. The variables used in this study are ROA, Inflation, NPF, and BOPO. The data used is aggregate data of all Sharia Commercial Banks recorded at Bank Indonesia. Measurement of Statistic Description, F-Test, T-Test, Correlation Coefficient, Coefficient of Determination and Multiple Linear Regression using IBM SPSS 21 software. The results showed that significant negative effect of BI rate, NPF and BOPO was found, while Inflation variable showed negative but not significant. Overall, the above variables affect the ROA of 87.7%, while 12.3% is likely to be influenced by other factors.

Lateral Adsorbate Interactions Inhibit HCOO- While Promoting CO Selectivity for CO2 Electrocatalysis on Ag

2018 ◽  
Author(s):  
Divya Bohra ◽  
Isis Ledezma-Yanez ◽  
Guanna Li ◽  
Wiebren De Jong ◽  
Evgeny A. Pidko ◽  
...  
Keyword(s):  
Electrochemical Reduction ◽  
Experimental Approach ◽  
Decisive Role ◽  
Experimental Methods ◽  
Reaction Intermediates ◽  
Intermediate Species ◽  
Experimental Knowledge ◽  
Complex Interactions ◽  
Ag Catalysts

<p>The analysis presented in this manuscript helps bridge an important fundamental discrepancy between the existing theoretical and experimental knowledge regarding the performance of Ag catalysts for CO<sub>2</sub> electrochemical reduction (CO<sub>2</sub>ER). The results demonstrate how the intermediate species *OCHO is formed readily en-route the HCOO<sup>– </sup>pathway and plays a decisive role in determining selectivity of a predominantly CO producing catalyst such as Ag. Our theoretical and experimental approach develops a better understanding of the nature of competition as well as the complex interactions between the reaction intermediates leading to CO, HCOO<sup>–</sup> and H<sub>2</sub> during CO<sub>2</sub>ER.</p><p><br></p><p>Details of computational and experimental methods are present in the Supporting Information provided. </p><p><br></p><p><br></p>

Combination Therapies Using Metformin and/or Valproic Acid in Prostate Cancer: Possible Mechanistic Interactions

2019 ◽  
Vol 19 (5) ◽  
pp. 368-381 ◽  
Author(s):  
Linh N.K. Tran ◽  
Ganessan Kichenadasse ◽  
Pamela J. Sykes
Keyword(s):  
Prostate Cancer ◽  
Valproic Acid ◽  
Androgen Receptor ◽  
Gene Fusion ◽  
Combination Therapies ◽  
Slowing Down ◽  
Castration Resistant ◽  
Local Pca ◽  
End Stage ◽  
Fusion Products

Prostate cancer (PCa) is the most frequent cancer in men. The evolution from local PCa to castration-resistant PCa, an end-stage of disease, is often associated with changes in genes such as p53, androgen receptor, PTEN, and ETS gene fusion products. Evidence is accumulating that repurposing of metformin (MET) and valproic acid (VPA) either when used alone, or in combination, with another therapy, could potentially play a role in slowing down PCa progression. This review provides an overview of the application of MET and VPA, both alone and in combination with other drugs for PCa treatment, correlates the responses to these drugs with common molecular changes in PCa, and then describes the potential for combined MET and VPA as a systemic therapy for prostate cancer, based on potential interacting mechanisms.

Transformation of methanol to hydrocarbons over Y zeolites with varying Si/Al ratio

1987 ◽  
Vol 52 (7) ◽  
pp. 1701-1707 ◽  
Author(s):  
Miloslav Křivánek ◽  
Nguyen Thiet Dung ◽  
Pavel Jírů
Keyword(s):  
Catalytic Activity ◽  
Reaction Time ◽  
Coke Formation ◽  
Aliphatic Hydrocarbons ◽  
Y Zeolite ◽  
Y Zeolites ◽  
Methanol To Hydrocarbons

The catalytic activity of Na, H-Y zeolite samples with a varying Si/Al ratio (2·5 to 20) in the transformation of methanol was determined. The amounts of formed individual aliphatic hydrocarbons as function of reaction time were correlated with the amount of Bronsted and Lewis centres on the catalysts. The effect of coke formation on the over-all course of the reaction has been demonstrated.

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