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The importance of cell design to the development of convenient, laboratory organic electrosyntheses, popular with synthetic chemists, is highlighted. Although also influencing reaction selectivity, the cell design is the major factor determining the rate of conversion of reactant to product, the final conversion that can be achieved and the quantity of product formed. The recent literature contains a number of designs of flow electrolysis cells for electrosynthesis with examples of their application. 相似文献
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Chemorheology investigation of a glassy epoxy thermoset on tensile plastic flow and fracture morphology 下载免费PDF全文
Stephen F. Foster Emily A. Hoff Greg W. Curtzwiler Eric B. Williams Kevin B. Davis Derek L. Patton James W. Rawlins 《Journal of Polymer Science.Polymer Physics》2015,53(19):1333-1344
Reproducible and uncharacteristic tensile stress–strain behavior of cured glassy epoxy‐amine networks produces distinctive fracture surfaces. Test specimens exhibiting plastic flow result in mirror‐like fracture surfaces, whereas samples that fail during yield or strain softening regions possess nominal mirror‐mist‐hackle topography. Atomic force microscopy and scanning electron microscopy reveal branched nodule morphologies in the 50‐nm size scale that may be responsible for the unusual tensile properties. Current hypothesis is that plastic flow of the glassy thermoset occurs through the existence and deformation of these nodular nanostructures. The thermal cure profile of the epoxy‐amine thermoset affects the size and formation of the nodular nanostructure. Eliminating vitrification during thermoset polymerization forms a more continuous phase, reduction in size of the nodules, and eliminates the capacity of the material to yield in plastic flow. This maximizes nanostructure connectivity of the glassy epoxy‐amine thermoset and reduces strain to failure significantly. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1333–1344. 相似文献
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Liam J. R. McGeachie Cameron L. Carpenter-Warren David B. Cordes Michael Bühl Steven J. Gray Guoxiong Hua Alexandra M. Z. Slawin J. Derek Woollins 《无机化学与普通化学杂志》2020,646(22):1795-1798
An improved route to d-block and main group NSO complexes is presented including the synthesis of the first antimony(V) complexes, (Ar3Sb(NSO)2), and copper examples [CuBipy(PPh3)NSO]. The structures of eight complexes are reported. The observed variation in M–N–S bond angles is due to the combination of orbital overlap (ligand-to-metal bonding) and the degree of ionicity of the bonding. 相似文献
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McLain Derek R. Brossard Tom W. Tsai Yifen Condon Nicholas J. Canaday Jodi L. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2169-2174
Journal of Radioanalytical and Nuclear Chemistry - Two methods were used to evaluate the age of 75Se sealed source material. Both methods utilized gamma spectroscopy to determine the quantity of... 相似文献
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Wei Mingyao Liu Jishan Shi Rui Elsworth Derek Liu Zhanghao 《Transport in Porous Media》2019,130(3):969-983
Transport in Porous Media - Understanding the long-term evolution of coal permeability under the influence of gas adsorption-induced multiple processes is crucial for the efficient sequestration of... 相似文献
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This paper presents a review of procedural steps and implementation techniques used in the development of artificial intelligence models, generally referred to as artificial neural networks (ANNs), within the water resources domain. It focusses on identifying different areas wherein ANNs have found application thereby elucidating its advantages and disadvantages as well as various challenges encountered in its use. Results from this review provide useful insights into how the performance of ANNs can be improved and potential areas of application that are yet to be explored in hydrological modeling. Recommendations for Resource Managers
- Development of integrated and hybrid artificial intelligent tools is critical to achieving improved forecasts in hydrological modeling studies.
- Further research into comprehending the internal mechanisms of neural networks is required to obtain a practical meaning of each network component deployed to solve real‐world problems.
- More robust optimization techniques and tools like differential evolution, particle swarm optimization and deep neural nets, are yet to be fully explored in the water resources analysis, and should be given more attention to enhance neural networks aptitude for modeling complex and nonlinear hydrological processes.
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Raana Kashfi‐Sadabad Laura Gonzalez‐Fajardo Derek Hargrove Bahar Ahmadi Daniel Munteanu Sina Shahbazmohamadi Michael Jay Xiuling Lu 《Particle & Particle Systems Characterization》2019,36(4)
Nonspecific high‐energy radiation for treatment of metastatic ovarian cancer is limited by damage to healthy organs, which can be mitigated by the use of radiosensitizers and image‐guided radiotherapy. Gold (Au) and tantalum oxide (TaOx) nanoparticles (NPs), by virtue of their high atomic numbers, find utility in the design of bimetallic NP systems capable of high‐contrast computed tomography (CT) imaging as well as a potential radiosensitizing effect. These two radio‐dense metals are integrated into dendritic mesoporous silica NPs (dMSNs) with radial porous channels for high surface‐area loading of therapeutic agents. This approach results in stable, monodispersed dMSNs with a uniform distribution of Au on the surface and TaOx in the core that exhibits CT attenuation up to seven times greater than iodine or monometallic dMSNs without either TaOx or Au. Tumor targeting is assessed in a metastatic ovarian cancer mouse model. Ex vivo micro‐CT imaging of collected tumors shows that these NPs not only accumulate at tumor sites but also penetrate inside tumor tissues. This study demonstrates that after intraperitoneal administration, rationally designed bimetallic NPs can simultaneously serve as targeted contrast agents for imaging tumors and to enhance radiation therapy in metastatic ovarian cancer. 相似文献
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