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91.
Ionic liquids are an interesting alternative to classical solvents presenting several advantages. A variety of catalysts show good or even enhanced activities when applied in ionic liquids. Oxidation catalysis represents a large segment of industrial chemistry, providing both bulk chemicals and intermediates for high value added special products and pharmaceuticals. Particularly for the latter products organometallic and inorganic catalysts are being developed that can be applied in systems consisting of or containing ionic liquids. This work provides an overview on recent developments in this field.  相似文献   
92.
Theoretical and Mathematical Physics - We present a supersymmetric generalization of a multicomponent coupled dispersionless (SUSY-MCD) integrable system. Expanding the superfields of the SUSY-MCD...  相似文献   
93.
The development of inexpensive and effective catalysts for the epoxidation of olefins to epoxides, which are key commodities for the chemical industry, is a continuing challenge. In this context, we present a supramolecular solution with the development of new host-guest assemblies of sulfate ions and amidoammonium receptor cations that, for the first time, are shown to act as catalysts for olefin epoxidation by hydrogen peroxide under biphasic conditions. Analysis of the reaction mechanism shows that the reactive and oxidizing peroxymonosulfate is formed in the organic phase. Furthermore, a variety of readily available precursors may be used to form the supramolecular ion pairs (SIPs), which is enabling a large-scale synthesis of the catalysts while maintaining catalytic control and effectiveness.  相似文献   
94.
This study investigated the effects of syringic acid (SA) on renal, cardiac, hepatic, and neuronal diabetic complications in streptozotocin-induced neonatal (nSTZ) diabetic rats. STZ (110 mg/kg i.p) was injected into Wistar rat neonates as a split dose (second and third postnatal day). Diabetes mellitus was diagnosed in adults by measuring fasting blood glucose levels, urine volume, and food and water intake. The treatment of SA (25 mg/kg, 50 mg/kg p.o) was given from the 8th to 18th postnatal week. To assess the development of diabetic complications and the effect of therapy, biochemical indicators in serum and behavioural parameters were recorded at specific intervals during the study period. SA (25 mg/kg, 50 mg/kg p.o) treatment reduced hyperglycaemia, polydipsia, polyphagia, polyuria, relative organ weight, cardiac hypertrophic indices, inflammatory markers, cell injury markers, glycated haemoglobin, histopathological score, and oxidative stress, and increased Na/K ATPase activity. These findings suggest that SA might significantly alleviate diabetic complications and/or renal, neuronal, cardiac, and hepatic damage in nSTZ diabetic rats.  相似文献   
95.
The object of this paper is to extend a result of Agnew in [1]for single series to double series, and so enable Tauberianconstants between matrix transformations of double sequencesto be calculated using the technique that many authors haveused previously for single sequences (see, for instance, [2,3, 8]). This method (see below) gives the best possible Tauberianconstants in the form of certain upper limits, and we attemptto calculate these for Cesàro summability with variousknown Tauberian conditions. In Section 2, we introduce our notationand review earlier work. In Section 3, we prove our main result,and we discuss applications to Cesàro summability inSection 4.  相似文献   
96.
97.
The next-nearest neighbor correlation function for isotropic triangular Ising system has been evaluated. This function is used to determine the shifts in the critical temperatures of ferromagnetic and antiferromagnetic triangular lattice after introduction of a small next-nearest neighbor interaction in zero field.  相似文献   
98.
The homology of GL n (R) and SL n (R) is studied, where R is a commutative ‘ring with many units’. Our main theorem states that the natural map H 4(GL3(R), k) → H 4(GL4(R), k) is injective, where k is a field with char(k) ≠ 2, 3. For an algebraically closed field F, we prove a better result, namely, is injective. We will prove a similar result replacing GL by SL. This is used to investigate the indecomposable part of the K-group K 4(R).  相似文献   
99.
Microwave‐assisted aromatization of 1,3,5‐trisubstituted 4,5‐dihydro‐1H‐pyrazoles by in‐situ generation of NO+ and NO2+ respectively from sodium nitrite and sodium nitrate in acetic acid has been carried out efficiently under mild reaction conditions in good to excellent yields.  相似文献   
100.
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