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排序方式: 共有380条查询结果,搜索用时 234 毫秒
1.
Syeda Wishal Bokhari Ahmad Hassan Siddique Xiaoyu Yue Harshpeet Singh Muhammad Dilawer Hayat Wei Gao 《国际能源研究杂志》2020,44(14):12197-12203
Reduced graphene oxide (rGO) has unique properties that can revolutionize the performance of the functional devices. rGO hybrids can be designed with transition metal oxides for improved energy storage applications. Herein, a hybrid composite of conductive rGO with titanium dioxide, designed by a simple hydrothermal method, is reported to demonstrate a high double layer capacitance in aqueous electrolyte systems. The mesoporous structure of the composite provides short ion diffusion pathways and the resultant capacitance of the material is 334 F g−1 with ~77% capacitance retention after 7000 charge-discharge cycles. 相似文献
2.
An unsteady stagnation point flow of a Maxwell fluid over a unidirectional linearly stretching sheet is studied under the influence of a magnetic field. The parabolic energy equation, which is based on parabolic Fourier law is replaced with a hyperbolic energy equation incorporating the heat flux model of Cattaneo–Christov. The Buongiorno model is used to characterize the properties of nanofluids using thermophoresis and Brownian diffusion coefficients. The phenomenon of melting heat transfer and slip mechanism is also embodied in the present study. Coupled nonlinear differential equations have appeared when the specified similarity transformations are applied. The mathematical problem is tackled via the homotopy analysis method. The impact of important physical parameters on the velocity, concentration, and temperature are highlighted via graphs. To verify our present results, a comparison is given with a limiting case with an already published article. It is witnessed through the graphs that the higher unsteadiness parameter and melting heat coefficient both are responsible for the reduction in the velocity and temperature of the nanofluid. Also, the velocity slip parameter detracts the velocity profile and affiliated boundary layer thickness of the Maxwell nanofluid. 相似文献
3.
Chemical oxygen demand (COD) assays are widely used for the estimation of the organic carbon content of water and wastewater. The procedure is subject to interference by free halogen ions, the oxidation of which creates artificially high COD values. As part of an investigation of the interferences involved in the COD determination of chemical industries wastewaters, we found that mercuric sulfate complexation, the standard procedure for neutralizing the halogen effects, is suitable for chlorides but is not applicable to bromides. This observation is true both in the presence or absence of chloride or ammonia. Care should therefore be exercised in the interpretation of COD data for bromide-containing samples. 相似文献
4.
Khushbu Kushwaha Balazs Pinter Syeda A. Shehzadi Chandi C. Malakar Christophe M. L. VandeVelde Frank deProft Kourosch AbbaspourTehrani 《Advanced Synthesis \u0026amp; Catalysis》2016,358(1):41-49
The metal‐free reaction of terminal arylacetylenes with α,α‐dichloroaldimines in 1,1,1,3,3,3‐hexafluoro‐2‐propanol as the sole solvent results in the rapid and selective formation of γ,γ‐dichloro‐β‐amino ketones. In this solvent the expected dichlorinated propargylamines and/or allylic amines are not formed. The dichloromethylene moiety of the aldimine acts as an activating group and is essential to accomplish this transformation. Electron‐rich acetylenes lead to the best results and work well with all imines (with or without α′‐H at the nitrogen substituent), while electron‐deficient acetylenes only reacted with N‐tert‐butylaldimines (no α′‐H). The mechanistic pathway showed 1,1,1,3,3,3‐hexafluoro‐2‐propanol to protonate the aldimine, which in the rate‐determining step will react with the arylacetylene to form a resonance‐stabilized allene cation, which is trapped by a HFIP molecule giving rise to an enol ether, which promptly hydrolyzes to furnish exclusively the β‐amino ketones. Using DFT techniques we found that the first C C bond forming step is the rate‐determining step and is associated with a barrier of about 21 kcal mol−1.
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A new kind of Stereoscopic Viewer is described which produces the illusion that the object viewed is actually in the room. 相似文献
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In High-Level Synthesis, Binary Synthesis is a method for synthesizing compiled applications for which the source code is
not available. One of the advantages of FPGAs over processors is the availability of multiple internal and external memory
banks. Binary synthesis tools use multiple memory banks if they are able to recover data-structures from the binary. In this
work we improve the recovery of data-structures by introducing dynamic memory analysis and combining it with improved static
memory analysis. We show that many applications can only be synthesized using dynamic memory analysis. We present two FPGA
based architectures for implementing the bound-checking and recovery for the synthesized code. Our experiments show that the
proposed technique accelerates the execution of applications which use multiple memory banks concurrently. We demonstrate
that many binary applications indeed benefit from this technique. 相似文献
9.
A Thieno[3,2‐b][1]benzothiophene Isoindigo Building Block for Additive‐ and Annealing‐Free High‐Performance Polymer Solar Cells 下载免费PDF全文
10.
Drug‐loaded microparticles prepared by the one‐step deposition of calcium carbonate/alginate onto cotton fabrics 下载免费PDF全文
Huan‐Ling Wu Xiao‐Xiao Hou Christopher Branford‐White Xiao‐Zhu Sun Lei Tao Syeda Um‐I‐Zahra Li‐Min Zhu 《应用聚合物科学杂志》2015,132(40)
Calcium carbonate (CaCO3)/alginate inorganic–organic hybrid particles were synthesized and deposited on to the surface of cotton fabrics with a novel one‐step procedure. The effects of the Ca2+/CO32?/alginate molar ratio on the cotton matrix were investigated. The optimization of the process resulted in a regular shaped hybrid microparticles, and scanning electron microscopy revealed that the particles were uniformly distributed on the surface of the fibers. Dynamic light scattering showed that the particles were about 2 μm in diameter. Moreover, transmission electron microscopy images demonstrated that the core–shell structure of the particles existed along with CaCO3 evenly enfolded into the alginate layer. An X‐ray diffraction pattern displayed that the alginate/CaCO3 hybrid microparticles were a mixture of calcite and vaterite crystal. Fourier transform infrared spectroscopy indicated that CaCO3/alginate hybrid particles formed in situ were the only deposited materials. The thermogravimetric analysis curve indicated a certain mass ratio of the alginate and CaCO3 in the hybrid particles. Furthermore, the drug‐loading and drug‐release properties of the hybrid microspheres were studied, and the results show that the water‐soluble diclofenac sodium could be effectively loaded in the hybrid microparticles and the drug release could be effectively sustained. Finally, both of the microparticles and modified fabrics had good cytocompatibility. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42618. 相似文献