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排序方式: 共有296条查询结果,搜索用时 109 毫秒
291.
Chaudhry AA Haque S Kellici S Boldrin P Rehman I Khalid FA Darr JA 《Chemical communications (Cambridge, England)》2006,(21):2286-2288
Nano-particle hydroxyapatite (HA) rods, were rapidly synthesised using a three pump continuous hydrothermal process (using a water feed at up to 400 degrees C and at 24 MPa): the product was obtained as a highly crystalline and phase pure material, without the need for an ageing step or subsequent heat treatment. 相似文献
292.
C. Masood Khalique Fazal M. Mahomed 《Nonlinear Analysis: Real World Applications》2009,10(4):2021-2025
We determine all the nontrivial conservation laws for soil water redistribution and extraction flow equations which are modelled by a class of (2+1) nonlinear evolution partial differential equations with three arbitrary elements. It is shown that for arbitrary elements in the model equation there exist trivial conservation laws. We point out that nontrivial conservation laws exist for certain classes of equations which admit point symmetries. 相似文献
293.
Anti-plane deformation of square lattices containing interphases is analyzed. It is assumed that lattices are linear elastic but not necessarily isotropic, whereas interphases exhibit non-linear elastic behavior. It is demonstrated that such problems can be treated effectively using Green’s functions, which allow to eliminate the degrees of freedom outside of the interphase. Illustrative numerical examples focus on the determination of applied stresses leading to lattice instability. 相似文献
294.
Nazrul Haq Adel F. Alghaith Sultan Alshehri Faiyaz Shakeel 《Molecules (Basel, Switzerland)》2022,27(13)
This study examines the solubility and thermodynamics of febuxostat (FBX) in a variety of mono solvents, including “water, methanol (MeOH), ethanol (EtOH), isopropanol (IPA), 1-butanol (1-BuOH), 2-butanol (2-BuOH), ethylene glycol (EG), propylene glycol (PG), polyethylene glycol-400 (PEG-400), ethyl acetate (EA), Transcutol-HP (THP), and dimethyl sulfoxide (DMSO)” at 298.2–318.2 K and 101.1 kPa. The solubility of FBX was determined using a shake flask method and correlated with “van’t Hoff, Buchowski-Ksiazczak λh, and Apelblat models”. The overall error values for van’t Hoff, Buchowski-Ksiazczak λh, and Apelblat models was recorded to be 1.60, 2.86, and 1.14%, respectively. The maximum mole fraction solubility of FBX was 3.06 × 10−2 in PEG-400 at 318.2 K, however the least one was 1.97 × 10−7 in water at 298.2 K. The FBX solubility increased with temperature and the order followed in different mono solvents was PEG-400 (3.06 × 10−2) > THP (1.70 × 10−2) > 2-BuOH (1.38 × 10−2) > 1-BuOH (1.37 × 10−2) > IPA (1.10 × 10−2) > EtOH (8.37 × 10−3) > EA (8.31 × 10−3) > DMSO (7.35 × 10−3) > MeOH (3.26 × 10−3) > PG (1.88 × 10−3) > EG (1.31 × 10−3) > water (1.14 × 10−6) at 318.2 K. Compared to the other combinations of FBX and mono solvents, FBX-PEG-400 had the strongest solute-solvent interactions. The apparent thermodynamic analysis revealed that FBX dissolution was “endothermic and entropy-driven” in all mono solvents investigated. Based on these findings, PEG-400 appears to be the optimal co-solvent for FBX solubility. 相似文献
295.
Yanan Zhang Junlei Chen Fazal Razq Chenyang Su Xuehan Hou Wenhuan Huang Huabin Zhang 《中国化学》2023,41(1):75-82
Metal organic frameworks have been employed as high-performance layered double hydroxide (LDH) composite supercapacitor electrode materials but have shown unsatisfactory redox ability and stability. Herein, a host-guest CuMo-based polyoxometalate-based metal organic framework (POMOF) with copious electrochemically active sites and strong electrochemical redox activities has been effectively coupled with POM-incorporated CoNi-LDH to develop a nanocomposite (NENU-5@CoNi-LDH) by a simple solvothermal method. The designed electrode shows a high specific capacity of 333.61 mAh·g–1 at 1 A·g–1. In addition, the novel hybrid symmetric supercapacitor NENU-5@CoNi-LDH/active carbon (AC) demonstrated a high energy density of 80.8 Wh·kg–1 at a power density of 750.7 W·kg–1. Interestingly, the nanocomposite of NENU-5@CoNi-LDH exhibits an outstanding capacitance retention of 79% after 5000 charge-discharge cycles at 10 A·g–1. This work provides a new strategy and will be the backbone for future energy storage research. 相似文献
296.
Mohammad Z. Rahman Fazal Raziq Huabin Zhang Jorge Gascon 《Angewandte Chemie (International ed. in English)》2023,62(48):e202305385
Transition metal oxides (TMOs) were one of the first photocatalysts used to produce hydrogen from water using solar energy. Despite the emergence of many other genres of photocatalysts over the years, TMO photocatalysts remain dominant due to their easy synthesis and unique physicochemical properties. Various strategies have been developed to enhance the photocatalytic activity of TMOs, but the solar-to-hydrogen (STH) conversion efficiency of TMO photocatalysts is still very low (<2 %), which is far below the targeted STH of 10 % for commercial viability. This article provides a comprehensive analysis of several widely used strategies, including oxygen defects control, doping, establishing interfacial junctions, and phase-facet-morphology engineering, that have been adopted to improve TMO photocatalysts. By critically evaluating these strategies and providing a roadmap for future research directions, this article serves as a valuable resource for researchers, students, and professionals seeking to develop efficient energy materials for green energy solutions. 相似文献