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921.
Long Lin Jingtao Huang Weiyang Yu Chaozheng He Hualong Tao Yonghao Xu Linghao Zhu Pengtao Wang Zhanying Zhang 《理论物理通讯》2020,72(3):35501-82
Gas molecules(such as CH4,CO,H2O,H2S,NH_3)adsorption on the pure and Au-doped WO3(001)surface have been studied by Density functional theory calculations with generalized gradient approximation.Based on the the calculation of adsorption energy,we found the most stable adsorption site for gas molecules by comparing the adsorption energies of different gas molecules on the WO3(001)surface.We have also compared the adsorption energy of five different gas molecules on the WO3(001)surface,our calculation results show that when the five kinds of gases are adsorbed on the pure WO3(001)surface,the order of the surface adsorption energy is CO>H2S>CH4>H2O>NH3.And the results show that NH3 is the most easily adsorbed gas among the other four gases adsorbed on the surface of pure WO3(001)surface.We also calculated the five different gases on the Au-doped WO3(001)surface.The order of adsorption energy was found to be different from the previous calculation:CO>CH4>H2S>H2O>NH3.These results provide a new route for the potential applications of Au-doped WO3 in gas molecules adsorption. 相似文献
922.
A design of ultrathin crystalline silicon solar cells patterned with α-NaEr_(0.2)Y_(0.8)F_4 upconversion nanosphere(NSs) arrays on the surface was proposed. The light trapping performance ofα-NaEr_(0.2)Y_(0.8)F_4 NSs with different ratios of sphere diameter to sphere pitch was systematically studied by COMSOL Multiphysics. The influence of different NS diameters and ratio to the average optical absorption of ultrathin crystalline silicon solar cell was calculated, as well as the short circuit current densities. The results show that the average optical absorption of solar cells with 2.33 μm silicon covered by α-NaEr_(0.2)Y_(0.8)F_4 NSs of 100 nm in diameter and 5.2 in ratio has improved by 8.5% compared to planar silicon solar cells with the same thickness of silicon. The light trapping performance of different thicknesses of silicon solar cells with the optimized configuration of NSs was also discussed. The results indicate that our structure enhances the light absorption. The presented model will be the basis for further simulations concerning frequency upconversion of α-NaEr_(0.2)Y_(0.8)F_4 materials. 相似文献
923.
Saturation-transfer difference (STD)-NMR spectroscopy has been widely used to screen potential ligands for binding to large receptor molecules. The STD-NMR experiment is typically based on a proton NMR spectrum, which can suffer from spectral overlap, leading to missing information in STD-based epitope mapping. Two-dimensional STD-NMR experiments can alleviate spectral overlap, but are time consuming. Here, we examine the feasibility of saturating protons in a receptor molecule and observing the STD effect on nearby carbon nuclei after transferring polarization from protons to carbons using the insensitive nuclei enhanced by polarization transfer (INEPT) pulse sequence. We show that under favorable conditions, a 1H→13C STD-INEPT experiment can give information similar to that obtained from a two-dimensional heteronuclear experiment, but in significantly less time. The STD-INEPT experiment could be especially useful when studying mixtures of ligands in which the peak positions in the proton and HSQC spectrum change significantly, and in particular, when using high-throughput, automated methods to analyze the data. 相似文献
924.
Artem Yakovliev Tymish Y. Ohulchanskyy Roman Ziniuk Tereza Dias Xin Wang Hao Xu Guanying Chen Junle Qu Anderson S. L. Gomes 《Particle & Particle Systems Characterization》2020,37(2):1900445
In this work, the application of near infrared (NIR)-emitting NaYbF4:1%Tm3+@NaLuF4:30%Nd3+ core–shell nanoparticles is reported for noninvasive probing and monitoring the temperature during photopolymerization of dental materials. When excited at 808 nm, the synthesized nanoparticles emit NIR photoluminescence (PL) with two distinctive peaks at 865 and 980 nm which correspond to radiative transitions from the doped Nd3+ and Yb3+ ions, respectively. Luminescence intensity ratio between these two bands is found to vary with temperature due to temperature-dependent electronic excitation energy transfer between Nd3+ and Yb3+ ions at the core/shell interface. This finding allows luminescence ratiometric evaluation of the in situ temperature during photopolymerization of resin cement (doped with nanoparticles) in a veneer placement procedure. In addition, the NIR emission also enables PL imaging of the distribution of the adhesive under the veneer. The results highlight that rare-earth ions–doped nanoparticles with both excitation and emission in the NIR spectral range are advantageous for both PL-based nanothermometry and imaging due to the reduced attenuation of NIR light by dental ceramics. 相似文献
925.
Xin Xu Yifan Jiang Min Wang Huimeng Wang Chunhua Lu Huanghao Yang 《Particle & Particle Systems Characterization》2020,37(12):2000243
Black phosphorus nanosheet (BPNS) is a promising multifunctional material in the biomedical field with biodegradability and low side effects, however its features are always weakened severely owing to its poor stability. Here, a novel method is developed for improving the defect of BPNS based on the effective protection of poly(lactic-co-glycolic acid) (PLGA), which preserves the stable photothermal therapy (PTT) effect of BPNS and biodegradability of the material. Meanwhile, doxorubicin (DOX) is loaded on BPNS/PLGA to get BPNS/PLGA/DOX for further chemotherapy and preventing the recurrence of tumor after PTT. The presented combined therapeutic strategy exploits the strengths and improves the defects of BPNS, thus developing an efficient and safe nanoagent for cancer therapy, which affords and reveals the great potential of BPNS in nanomedicine. 相似文献
926.
通过第一性原理对平面内双轴应力作用下的单层黑磷能带结构进行了计算.双轴拉伸应力作用下单层黑磷始终保持直接带隙性质,双轴压缩应力作用下的单层黑磷则发生了直接带隙转变为间接带隙的现象,当双轴压缩应力增加到7%时单层黑磷带隙闭合. 相似文献
927.
928.
本文使用波长为2.8 μm的分布式反馈激光器来测量水汽辉光放电产生的物种. 使用浓度调制光谱仅观察到OH自由基和瞬态H2O分子的吸收光谱. 吸收峰的强度和方向随解调相位而变化,但是H2O的一个吸收峰的方向始终与其它峰相反. OH和H2O的不同光谱取向反映了能级中粒子数量的增加或减少. 如果在放电过程中可以检测到更多的瞬态物种,则可以更好地研究H2O的激发、电离和分解动力学. 研究表明,浓度调制光谱的解调相位关系可以用来研究分子能级的布居数变化. 相似文献
929.
Journal of Visualization - A nanofluid containing copper (Cu) nanoparticles was simulated in a rectangular cavity using computational fluid dynamic (CFD). The upper and lower walls of the cavity... 相似文献
930.
The eight-band κ·p model is used to establish the energy band structure model of the type-II InAs/GaSb superlattice detectors with a cut-off wavelength of 10.5μm,and the best composition of M-structure in this type of device is calculated theoretically.In addition,we have also experimented on the devices designed with the best performance to investigate the effect of the active region p-type doping temperature on the quantum efficiency of the device.The results show that the modest active region doping temperature(Be:760℃)can improve the quantum efficiency of the device with the best performance,while excessive doping(Be:>760℃)is not conducive to improving the photo response.With the best designed structure and an appropriate doping concentration,a maximum quantum efficiency of 45% is achieved with a resistance-area product of 688?·cm^2,corresponding to a maximum detectivity of 7.35×10^11cm·Hz^1/2/W. 相似文献