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21.
Dr. Neeta Karjule Jesús Barrio Jonathan Tzadikov Prof. Menny Shalom 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6622-6628
The design of charge separation sites under illumination in semiconductors is a standing challenge for their utilization as photo(electro)catalysts. Here, the synthesis of modified carbon nitride materials (CNs) with donor–acceptor (D–A) domains, with altering electronic structure, is reported. To do so, new monomers based on polycyclic aromatic hydrocarbons (PAH)-substituted 1,3,5-triazine were designed, which were then embedded within cyanuric acid–melamine supramolecular assemblies to form CN precursors. The conjugation degree of PAHs was systematically changed, from single benzene ring up to pyrene unit, elucidating the role of the conjugation degree on the morphology, structure and electronic properties as well as photo(electro)catalytic activity. The careful design of the D–A sites results in excellent photocatalytic activity as well as long-term stability for the hydrogen evolution reaction. Moreover, PAH–CNs films exhibit enhanced charge separation, optical absorption, electrochemical surface area and electronic conductivity, leading to an outstanding photoelectrochemical (PEC) activity compared to pristine CN. 相似文献
22.
Babasaheb P. Bandgar Sampada V. Bettigeri Neeta S. Joshi 《Monatshefte für Chemie / Chemical Monthly》2004,135(10):1265-1273
Summary. Highly rapid and convenient syntheses of bis(indolyl)methanes in excellent yields were carried out using the inexpensive and easily available catalyst, hexamethylenetetraamine-bromine (HMTAB). Mild reaction conditions, short reaction times, and excellent yields are important features of this method. 相似文献
23.
Kinetics,Mechanism, and Rheological Properties of the Copolymers of 2-Ethylhexylacrylate and Styrene
Abstract Copolymerization of 2-ethylhexylacrylate (2-EHA) and styrene (Sty) initiated by α,α′-azobisisobutyronitrile (AIBN) was carried out at 60, 65, and 70 ± 0.1°C in bulk in the presence of zinc chloride (ZnCl2). R p was a direct function of [ZnCl2] and temperature. R p showed an initial increase with [monomers] followed by a subsequent decrease after a maximum was reached. The accelerating effect of ZnCl2 was predicted by a lowering of the activation energy from 42.78 to 34.38 kJ·mol?1 and an increase in the specific rate constants ratio (k 2 p/k t) from 4.64 to 5.83 L·mol?1·s?1. The product of the reactivity ratios of the two monomers was 0.018 and 0.648, favoring alternating and random copolymer structures, respectively. The copolymerization reaction mechanism was a radical complex. Rheological investigations favored Bingham and Ostwald models for the flow behaviors of alternating and random copolymers, respectively. 相似文献
24.
In this paper a necessary and sufficient condition has been obtained for Σan∈n to be summable |N, q| whenever Σan is bounded (N, p, q). 相似文献
25.
Tuberculosis remains a major global public health problem. Given the need for extensive analysis of antitubercular drugs, the development of sensitive, reliable and facile analytical methods to determine these compounds becomes necessary. Electrochemical techniques have inherent advantages over other well-established analytical methods, this review aiming to provide an updated overview of the latest trends (from 2006 till date) in the voltammetric determination of antitubercular drugs. Furthermore, the advantages and limitations of these methods are critically discussed. The review reveals that in spite of using a variety of chemically modified electrodes to determine antitubercular drugs, there is still a dearth of applicability of the voltammetric methods to quantify these compounds in human body fluids, especially in blood plasma. 相似文献
26.
A study of the self-organization of nonionic surfactant span 60 (sorbitan mono stearate) in presence of fatty alcohol (stearyl, cetyl and lauryl) is presented. When ethanolic solution of the surfactant–fatty alcohol (1:1) mixture is added in water spontaneous large unilamellar vesicles (LUV) are formed which may potentially be useful vehicles for drug delivery purposes. Vesicular suspension has been characterized by transmission electron microscopy, dynamic light scattering, confocal laser scanning microscopy, dye entrapment and release studies. Surface tension measurement indicates the suitability of fatty alcohols towards spontaneous vesicle formation from span 60. 相似文献
27.
Mohite Neeta Shinde Manish Gupta Arun Kumar Waghadkar Yogesh Gosavi Suresh W. Mohite K. C. Chauhan Ratna Rane Sunit 《Journal of Solid State Electrochemistry》2020,24(2):273-281
Journal of Solid State Electrochemistry - In present study, hollow urchin-like nanostructures of Nb2O5 with elongated nanofilaments as photoanode material for dye-sensitized solar cells (DSSCs) are... 相似文献
28.
Use of indigenous microwave system for dissolution and treatment of waste from nuclear materials 总被引:1,自引:0,他引:1
R. K. Malav Neeta D. Save Amrit Prakash Md. Afzal J. P. Panakkal 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(1):425-430
Microwave heating technique has the unique advantages of low processing time, less consumption of reagents, homogeneous heating and maintenance-free adaptability to glove box. Dissolution of thorium and plutonium containing fuel viz sintered thorium oxide, thorium-uranium oxide and thorium-plutonium oxide pellets is one of the most difficult step for their analysis and characterization. Complete dissolution of the fuel samples is a pre-requisite for the analysis of fuel material in the solution form. Even a trace level of un-dissolved particle may interfere with the accurate and precise determination in the analysis. Large volumes of liquid and solid wastes are generated during the processing and analysis of samples. These wastes being radioactive can’t be disposed directly to sea or soil. They have to be segregated and categorised and all possibilities are explored to see the feasibility of retrieving the precious nuclear material. The present paper describes an overview of all the efforts made at AFFF for rapid dissolution of nuclear materials using an indigenous microwave digestion system as well as its use for the treatment of waste being generated. 相似文献
29.
Structurally diverse aldehydes are successfully converted into 1,1‐diacetates with acetic anhydride using cyanuric chloride as a mild, convenient and inexpensive catalyst under solvent‐free conditions. The noteworthy features of the present system are shorter reaction times, and mild and solvent‐free conditions. Furthermore, it offers chemoselective protection of aldehydes. 相似文献
30.
Babasaheb P. Bandgar Neeta S. Joshi Sampada V. Bettigeri 《Monatshefte für Chemie / Chemical Monthly》2007,52(12):67-71
A mild and efficient transthioacetalization of aldehyde acetals and oxathioacetals was carried out using 2,4,6-trichloro-1,3,5-triazine
as a mild and inexpensive catalyst. Chemoselective transacetalization is impressive as aldehyde O,O- and O,S-acetals are converted into the corresponding S,S-acetals in the presence of ketones or their acetals and oxathiocetals in nearly quantitative yields. 相似文献