Cooperative effects of inorganic and organic structure-directing agents in ZSM-5 crystallization

2018 ◽  
Vol 3 (1) ◽  
pp. 159-170 ◽  
Author(s):  
Aseem Chawla ◽  
Rui Li ◽  
Rishabh Jain ◽  
R. John Clark ◽  
James G. Sutjianto ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Molecular Modelling ◽  
Synergistic Effects ◽  
Cooperative Effects ◽  
Bulk Crystallization ◽  
Organic Structure ◽  
Structure Directing Agents ◽  
Inorganic And Organic

A combination of bulk crystallization studies and molecular modelling are used to elucidate the role of dual inorganic/organic SDAs in ZSM-5 synthesis. Our findings reveal unexpected synergistic effects on crystallization times and physicochemical properties.

The Role of Template Structure and Synergism between Inorganic and Organic Structure Directing Agents in the Synthesis of UTL Zeolite

2010 ◽  
Vol 22 (11) ◽  
pp. 3482-3495 ◽  
Author(s):  
Oleksiy V. Shvets ◽  
Natalia Kasian ◽  
Arnošt Zukal ◽  
Jiří Pinkas ◽  
Jiří Čejka
Keyword(s):  
Organic Structure ◽  
Template Structure ◽  
Structure Directing Agents ◽  
Inorganic And Organic

scholarly journals Inhibition of Pancreatic α-amylase by Resveratrol Derivatives: Biological Activity and Molecular Modelling Evidence for Cooperativity between Viniferin Enantiomers

Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3225 ◽  
Author(s):  
Luce M. Mattio ◽  
Mauro Marengo ◽  
Chiara Parravicini ◽  
Ivano Eberini ◽  
Sabrina Dallavalle ◽  
...  
Keyword(s):  
Synergistic Effects ◽  
Total Concentration ◽  
Biological Evaluation ◽  
Reference Drug ◽  
Docking Analysis ◽  
Cooperative Effects ◽  
Resveratrol Derivatives ◽  
Bioactive Agents ◽  
The Individual

To improve the current understanding of the role of stilbenoids in the management of diabetes, the inhibition of the pancreatic α-amylase by resveratrol derivatives was investigated. To approach in a systematic way, the mechanistic and structural aspects of the interaction, potential bioactive agents were prepared as single molecules, that were used for the biological evaluation of the determinants of inhibitory binding. Some dimeric stilbenoids—in particular, viniferin isomers— were found to be better than the reference drug acarbose in inhibiting the pancreatic α-amylase. Racemic mixtures of viniferins were more effective inhibitors than the respective isolated pure enantiomers at an equivalent total concentration, and displayed cooperative effects not observed with the individual enantiomers. The molecular docking analysis provided a thermodynamics-based rationale for the measured inhibitory ability and for the observed synergistic effects. Indeed, the binding of additional ligands on the surface of the alpha-amylase was found to decrease the dissociation constant of inhibitors bound to the active site of the enzyme, thus providing a mechanistic rationale for the observed inhibitory synergies.

Characteristics Of The Structure Formation Of Gypsum Binder Modified With Zinc Hydrosilicates

2020 ◽  
pp. 40-46
Keyword(s):  
Synergistic Effect ◽  
Physicochemical Properties ◽  
Structure Formation ◽  
Silicic Acid ◽  
Chemical Properties ◽  
Crystal Formation ◽  
Ability To Act ◽  
Chemical Factors ◽  
Sorption Characteristics

The authors' methodic for assessing the role of chemical and physic-chemical factors during the structure formation of gypsum stone is presented in the article. The methodic is also makes it possible to reveal the synergistic effect and to determine the ranges of variation of controls factors that ensure maximum values of such effect. The effect of a micro-sized modifier based on zinc hydro-silicates on the structure formation of building gypsum is analyzed and corresponding dependencies are found. It is shown that effects of influence of modifier on the properties of gypsum compositions are determined by chemical properties of modifier. Among the mentioned properties are sorption characteristics (which depend on the amount of silicic acid and its state) and physicochemical properties - the ability to act as a substrate during crystal formation. The proposed method can also be extended to other binding substances and materials. This article contributes to the understanding of the processes that occur during the structure formation of composites, which will make it possible to control the structure formation in the future, obtaining materials with a given set of properties.

A BRIEF ANALYSIS OF TIME-PREPOSITIONS IN THE RUSSIAN LANGUAGE

2019 ◽  
Vol 18 (28) ◽  
pp. 187-195
Author(s):  
Yabing Zhang
Keyword(s):  
Foreign Language ◽  
Foreign Students ◽  
Russian Language ◽  
Parts Of Speech ◽  
Organic Structure ◽  
Part Of Speech ◽  
True Meaning ◽  
Oral Speech ◽  
The Russian Language

This article is devoted to the problem of using Russian time-prepositions by foreigners, especially by the Chinese. An analysis of modern literature allows the author to identify the main areas of the work aimed at foreign students’ development of the skills and abilities to correctly build the prepositional combinations and continuously improve the communication skills by means of the Russian language. In this paper, the time-prepositions in the Russian language have been analyzed in detail; some examples of polysemantic use of prepositions, their semantic and stylistic shades alongside with possible errors made by foreign students are presented. The results of the study are to help in developing a system of teaching Russian time-prepositions to a foreign language audience, taking into account their native language, on the basis of the systemic and functional, communicative and activity-centred basis. The role of Russian time-prepositions in constructing word combinations has been identified; the need for foreign students’ close attention to this secondary part of speech has been specified. It has been stated that prepositions are the most dynamic and open type of secondary language units within the quantitative and qualitative composition of which regular changes take place. The research substantiates the need that students should be aware of the function of time-preposition in speech; they are to get acquainted with the main time-prepositions and their meanings, to distinguish prepositions and other homonymous parts of speech as well as to learn stylistic shades of time-prepositions. Some recommendations related to the means of mastering time-prepositions have been given: to target speakers to assimilate modern literary norms and, therefore, to teach them how to choose and use them correctly by means of linguistic keys that are intended to fill the word with true meaning, to give it an organic structure, an inherent form and an easy combinability in the texts and oral speech.

Synergistic Methodology Based on Ion Exchange and Biodegradation Mechanisms Applied for Metal Complex Dye Removal from Waste Waters

2018 ◽  
Vol 69 (1) ◽  
pp. 38-44
Author(s):  
Nicoleta Mirela Marin ◽  
Olga Tiron ◽  
Luoana Florentina Pascu ◽  
Mihaela Costache ◽  
Mihai Nita Lazar ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Synergistic Effects ◽  
Freundlich Isotherm ◽  
White Rot ◽  
White Rot Fungus ◽  
Basic Anion Exchange Resin ◽  
Km Value ◽  
Points Of View ◽  
Basic Anion

This study investigates the synergistic effects of ion exchange and biodegradation methods to remove the Acid Blue 193 also called Gryfalan Navy Blue RL (GNB) dye from wastewater. Ion exchange studies were performed using a strongly basic anion exchange resin Amberlite IRA 400. The equilibrium was characterized by a kinetic and thermodynamic points of view, establishing that the sorption of the GNB dye was subject to the Freundlich isotherm model with R2 = 0.8710. Experimental results showed that the activated resin can removed up to 93.4% when the concentration of dye solution is 5.62�10-2 mM. The biodegradation of the GNB was induced by laccase, an enzyme isolated from white-rot fungus. It was also analyzed the role of pH and dye concentration on GNB biodegradation, so 5�10-2 mM dye had a maximum discoloration efficiency of 82.9% at pH of 4. The laccase showed a very fast and robust activity reaching in a few minutes a Km value of 2.2�10-1mM. In addition, increasing the GNB concentration up to 8�10-1 mM did not triggered a substrat inhibition effect on the laccase activity. Overall, in this study we proposed a mixt physicochemical and biological approach to enhance the GNB removal and biodegradability from the wastewaters and subsequently the environment.

scholarly journals Role of Physical Exercise and Nutraceuticals in Modulating Molecular Pathways of Osteoarthritis

2021 ◽  
Vol 22 (11) ◽  
pp. 5722
Author(s):  
Alessandro de Sire ◽  
Nicola Marotta ◽  
Cinzia Marinaro ◽  
Claudio Curci ◽  
Marco Invernizzi ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Synergistic Effects ◽  
Molecular Pathways ◽  
Epigenetic Changes ◽  
Pathological Features ◽  
Oxidative Signaling ◽  
Cartilage Extracellular Matrix ◽  
Wide Range ◽  
Comprehensive Picture

Osteoarthritis (OA) is a painful and disabling disease that affects millions of patients. Its etiology is largely unknown, but it is most likely multifactorial. OA pathogenesis involves the catabolism of the cartilage extracellular matrix and is supported by inflammatory and oxidative signaling pathways and marked epigenetic changes. To delay OA progression, a wide range of exercise programs and naturally derived compounds have been suggested. This literature review aims to analyze the main signaling pathways and the evidence about the synergistic effects of these two interventions to counter OA. The converging nutrigenomic and physiogenomic intervention could slow down and reduce the complex pathological features of OA. This review provides a comprehensive picture of a possible signaling approach for targeting OA molecular pathways, initiation, and progression.

scholarly journals Alcohol-assisted synthesis of high-silica zeolites in the absence of organic structure-directing agents

2021 ◽  
Vol 42 (4) ◽  
pp. 563-570
Author(s):  
Huimin Luan ◽  
Chi Lei ◽  
Ye Ma ◽  
Qinming Wu ◽  
Longfeng Zhu ◽  
...  
Keyword(s):  
Organic Structure ◽  
High Silica ◽  
High Silica Zeolites ◽  
Structure Directing Agents

scholarly journals The Role of H2C2O4 and Na2CO3 as Precipitating Agents on The Physichochemical Properties and Photocatalytic Activity of Bismuth Oxide

2020 ◽  
Vol 18 (1) ◽  
pp. 129-137
Author(s):  
Yayuk Astuti ◽  
Rizka Andianingrum ◽  
Abdul Haris ◽  
Adi Darmawan ◽  
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Physicochemical Properties ◽  
Bismuth Oxide ◽  
Rate Constants ◽  
Degradation Rate ◽  
Precipitation Method ◽  
Methyl Orange Degradation ◽  
Methyl Orange Dye

AbstractSynthesis of bismuth oxide synthesis through the precipitation method using H2C2O4 and Na2CO3 precipitating agents, identification of physicochemical properties and its photocatalysis activity for methyl orange degradation were conducted. The bismuth oxide synthesis was undertaken by dissolving Bi(NO3)3.5H2O in HNO3, then added precipitating agents to form precipitate. The results showed that bismuth oxide produced by H2C2O4 precipitating agent was a yellow powder containing a mixture of α-Bi2O3 (monoclinic) and β-Bi2O3 (tetragonal), porous with size of 28-85 μm. Meanwhile, the use of Na2CO3 as precipitating agent resulted in bismuth oxide consisting of α-Bi2O3 and β-Bi2O3 and Bi2O4, irregular shape without pore being 40-115 μm in size. Bismuth oxide synthesized with H2C2O4 precipitating agent showed higher photocatalytic activity compared to bismuth oxide synthesized using Na2CO3 on degrading methyl orange dye with degradation rate constants of 2.35x10-5 s-1 for H2C2O4 and 1.81x10-5 s-1 for Na2CO3.

scholarly journals Towards a Paradigm Shift in Polar Organometallic Chemistry

2020 ◽  
Vol 74 (9) ◽  
pp. 681-688 ◽  
Author(s):  
Eva Hevia
Keyword(s):  
Organometallic Chemistry ◽  
Synergistic Effects ◽  
Chemical Properties ◽  
Deep Eutectic Solvents ◽  
Chemical Transformations ◽  
Organometallic Reagents ◽  
Cooperative Effects ◽  
Bond Forming ◽  
Synthetic Methodologies ◽  
Metal Reagents

Core tools of synthetic chemistry, polar organometallic reagents (typified by organolithium and Grignard reagents) are used worldwide for constructing compounds, especially aromatic compounds, which are ubiquitous in organic chemistry and thus in numerous commodities essential to everyday life. By isolation and characterisation of key organometallic intermediates, research in our group has led to the design of polar mixed-metal reagents imbued with synergistic effects that display chemical properties and reactivity profiles far exceeding the limits of traditional single-metal reagents. These studies have improved existing, or established new fundamentally important, synthetic methodologies based on either stoichiometric or catalytic reactions. Bimetallic cooperative effects have been demonstrated in an impressive array of important bond forming reactions including deprotonative metallation, transition metal-free C–C bond formation and metal–halogen exchange to name just a few. Towards greener, more sustainable, safer chemical transformations, our group has also pioneered the use of polar organometallic reagents under air and/or with water present using biorenewable solvents such as Deep Eutectic Solvents (DES) and 2-methyl THF. Herein we summarize some of our recent efforts in this intriguing area, which we believe can make inroads towards a step change in the practice and future scope of polar organometallic chemistry.

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