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41.
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光纤表面等离子体共振传感器在高灵敏度传感和在线实时监测等领域具有重要意义. 设计了一种六重准晶体结构环形通道光纤表面等离子体共振传感器, 基于有限元法对该传感器的传感特性进行了数值模拟. 研究了光纤各结构参量对传感器特性的影响规律. 研究结果表明: 待测液折射率的有效监测范围为1.25–1.331, 最高灵敏度可达26400 nm·RIU-1, 传感器具有损耗谱杂峰少、探测范围广、灵敏度高、设计灵活性高和光路可弯曲等特点, 在生化检测、公共安全、环境污染监测以及高灵敏度传感等领域具有广泛的应用前景. 相似文献
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44.
Dong Yang Pei Liu Wanran Lin Shanglin Sui Long‐Biao Huang Ben Bin Xu Jie Kong 《化学:亚洲杂志》2020,15(16):2499-2504
Hyperbranched polymers have garnered much attention due to attractive properties and wide applications, such as drug‐controlled release, stimuli‐responsive nano‐objects, photosensitive materials and catalysts. Herein, two types of novel hyperbranched poly(ester‐enamine) (hb‐PEEa) were designed and synthesized via the spontaneous amino‐yne click reaction of A2 monomer (1, 3‐bis(4‐piperidyl)‐propane (A2a) or piperazine (A2b)) and B3 monomer (trimethylolpropanetripropiolate). According to Flory's hypothesis, gelation is an intrinsic problem in an ideal A2+B3 polymerization system. By controlling the polymerization conditions, such as monomer concentration, molar ratio and rate of addition, a non‐ideal A2+B3 polymerization system can be established to avoid gelation and to synthesize soluble hb‐PEEa. Due to abundant unreacted alkynyl groups in periphery, the hb‐PEEa can be further functionalized by different amino compounds or their derivates. The as‐prepared amphiphilic PEG‐hb‐PEEa copolymer can readily self‐assemble into micelles in water, which can be used as surfactant to stabilize Au nanoparticles (AuNPs) during reduction of NaBH4 in aqueous solution. As a demonstration, the as‐prepared PEG‐hb‐PEEa‐supported AuNPs demonstrate good dispersion in water, solvent stability and remarkable catalytic activity for reduction of nitrobenzene compounds. 相似文献
45.
Qingyun Zheng Tian Wang Guo-Chao Chu Chong Zuo Rui Zhao Xin Sui Linzhi Ye Yuanyuan Yu Jingnan Chen Xiangwei Wu Wenhao Zhang Prof. Haiteng Deng Prof. Jing Shi Dr. Man Pan Prof. Yi-Ming Li Prof. Lei Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(32):13598-13603
Triazole-based deubiquitylase (DUB)-resistant ubiquitin (Ub) probes have recently emerged as effective tools for the discovery of Ub chain-specific interactors in proteomic studies, but their structural diversity is limited. A new family of DUB-resistant Ub probes is reported based on isopeptide-N-ethylated dimeric or polymeric Ub chains, which can be efficiently prepared by a one-pot, ubiquitin-activating enzyme (E1)-catalyzed condensation reaction of recombinant Ub precursors to give various homotypic and even branched Ub probes at multi-milligram scale. Proteomic studies using label-free quantitative (LFQ) MS indicated that the isopeptide-N-ethylated Ub probes may complement the triazole-based probes in the study of Ub interactome. Our study highlights the utility of modern protein synthetic chemistry to develop structurally and new families of tool molecules needed for proteomic studies. 相似文献
46.
To decrease the performance difference between the actual microscanning thermal imager and the theoretical value, a germanium lens (placed at a certain angle between the infrared focal plane array and infrared lens) dip angle model of flat optical component microscanning is introduced in this letter. The model is the basis for choosing the dip angle of the germanium lens, which is used in the microscanning thermal imager. In addition, the actual dip angle of the germanium lens is chosen according to the model, the infrared lens parameters of the thermal imager, and the germanium lens parameters of manufacture and installation. Only in this manner can the optimal performance of the microscanning thermal imager based on the flat optical component be obtained. Results of the experiments confirm the accuracy of the conclusions above. 相似文献
47.
Huirui Zhou Ke Tao Yunqi Sui Kang Sun 《Physica E: Low-dimensional Systems and Nanostructures》2011,44(3):597-604
The heterogeneous nucleation and growth of CdSe domains on the Fe3O4 seed nanocrystals are hard to be controlled because of significant lattice mismatch between Fe3O4 and CdSe nanocrystals. Current study exploits the choice of surface ligand and crystal morphology for Fe3O4 seed to investigate ways to overcome the energy barrier imposed by the lattice mismatch for the promotion and control of subsequent growth of CdSe nanocrystals on seeded crystals. Results indicate that the growth of CdSe domains on seed nanocrystals not only depends on the affinity of ligands toward seed nanocrystals, but also is affected by the seed ligands in a similar way to synthesizing individual second-domain nanocrystals. Furthermore, preferential growth of CdSe domains on the corner of cubic seeds are observed, and cubic Fe3O4 nanocrystals are favored for the heterogeneous nucleation of CdSe as opposed to spherical ones. A three-stage growth model (heterostructures formation, the adsorption of Se and the heterogeneous nucleation and growth) is proposed, where choice of ligands, geometry features, such as surface curvature and defects are found to have significant impact to overcome energy barrier from lattice mismatch. 相似文献
48.
Hao Cheng Xiujian Zhao Xiaotao Sui Yuli Xiong Jiang Zhao 《Journal of nanoparticle research》2011,13(2):555-562
CdS quantum dot (Qd)-sensitized TiO2 nanotube array photoelectrode is synthesised via a two-step method on tin-doped In2O3-coated (ITO) glass substrate. TiO2 nanotube arrays are prepared in the ethylene glycol electrolyte solution by anodizing titanium films which are deposited
on ITO glass substrate by radio frequency sputtering. Then, the CdS Qds are deposited on the nanotubes by successive ionic
layer adsorption and reaction technique. The resulting nanotube arrays are characterized by scanning electron microscopy,
X-ray diffraction (XRD) and UV–visible absorption spectroscopy. The length of the obtained nanotubes reaches 1.60 μm and their
inner diameter and wall thickness are around 90 and 20 nm, respectively. The XRD results show that the as-prepared TiO2 nanotubes array is amorphous, which are converted to anatase TiO2 after annealed at 450 °C for 2 h. The CdS Qds deposited on the TiO2 nanotubes shift the absorption edge of TiO2 from 388 to 494 nm. The results show that the CdS-sensitized TiO2 nanotubes array film can be used as the photoelectrode for solar cells. 相似文献
49.
In this paper, we present a new self-adaptive alternating direction method for solving a class of variational inequality problems with both linear equality and inequality constraints without the need to add any extra slack variables. The method is simple because it needs only to perform some projections and function evaluations. In addition, to further enhance its efficiency, we adopt a self-adaptive strategy to adjust parameter μ at each iteration. Convergence of the proposed method is proved under certain conditions. Numerical experience illustrates the efficiency of the new method. 相似文献
50.