排序方式: 共有28条查询结果,搜索用时 15 毫秒
1.
研究了冷原子与法布里-珀罗腔内拉盖尔-高斯横模强耦合相互作用体系的透射光谱, 分析了透射光谱与原子在腔中运动轨迹的关系. 结果表明, 与厄米特-高斯横模相比, 拉盖尔-高斯横模的腔场与原子的最大耦合系数几乎不随阶数的增加而变化, 使得探测光谱的对比度受模式阶数的影响较小. 在拉盖尔-高斯横模场分布的圆环边缘附近, 原子运动轨迹的微小偏移会引起透射光谱的很大变化, 因此在这些位置可以实现原子运动轨迹的高精度探测. 相似文献
2.
Wei-Ting Chen Wei-Chun Chen Kuang-Hua Hsueh Chen-Wei Chiu Chi-Min Shu 《Journal of Thermal Analysis and Calorimetry》2014,118(2):1085-1094
The rapid development of the petrochemical industry of Taiwan over the past four decades has resulted in a booming economy in Taiwan that drives derived industries to develop progressively. However, it has also caused many runaway reaction accidents, such as toxic gas release, fire, and explosion. It is crucial to eliminate those potential hazard factors which can induce consequent runaway reaction accidents during the life span of the manufacturing process. In response to this crucial issue, we performed a thermokinetic parameter analysis for 1,1-bis-(tert-butylperoxy)-3,3,5-trimethylcyclohexane at isothermal conditions to conduct a thermal safety assessment of chemical materials. The five isothermal temperatures, 90, 100, 110, 120, 130, and 140 °C, measured by DSC, were adopted in this study to calculate process safety parameters, including TMRad, T NR, and SADT, which can be employed in process safety parameters for the manufacturing process. A novel, green kinetic approach accompanied with non-isothermal DSC results is used to derive thermokinetic parameters in safety protocol in this study. 相似文献
3.
Xiao-Rong Wu Chen-Wei Wu Fei Ding Cheng Tian Wen Jiang Cheng-De Mao Chuan Zhang 《中国化学快报》2017,28(4):851-856
Discrete and symmetric three-dimensional(3D)DNA nanocages have been revoked as excellent candidates for various applications,such as guest component encapsulation and organization(e.g.dye molecules,proteins,inorganic nanoparticles,etc.)to construct new materials and devices.To date,a large variety of DNA nanocages has been synthesized through assembling small individual DNA motifs into predesigned structures in a bottom-up fashion.Most of them rely on the assembly using multiple copies of single type of motifs and a few sophisticated nanostructures have been engineered by co-assembling multi-types of DNA tiles simultaneously.However,the availability of complex DNA nanocages is still limited.Herein,we demonstrate that highly symmetric DNA nanocages consisted of binary DNA point-star motifs can be easily assembled by deliberately engineering the sticky-end interaction between the component building blocks.As such,DNA nanocages with new geometries,including elongated tetrahedron(E-TET),rhombic dodecahedron(R-DOD),and rhombic triacontahedron(R-TRI)are successfully synthesized.Moreover,their design principle,assembly process,and structural features are revealed by polyacryalmide gel electrophoresis(PAGE),atomic force microscope(AFM)imaging,and cryogenic transmission electron microscope imaging(cryo-TEM)associated with single particle reconstruction. 相似文献
4.
Jaw-Luen Tang Chen-Wei Chen Jiunn-Yuan Lin Chia-Chen Hsu Tzer-Hsiang Huang 《Optics Communications》2006,266(2):669-675
Transient optical Kerr effect of liquids C2H4Cl2 and C2H4Br2 is investigated, for the first time to our knowledge, with a femtosecond (fs) probe laser delayed with respect to a coherent fs pump laser. Coherent coupling and electronic Kerr signals are observed around zero delay when pump and probe overlap. Persisting after the pump-probe overlap are Kerr signals arising from the torsional and other intramolecular vibrations of the trans and gauche conformations; Kerr signals arising from the intermolecular motion are also observed. Vibrational quantum interference is only observed in liquid C2H4Br2 and the related beats data are fitted with the torsional vibrations, 91 cm−1 (gauche) and 132 cm−1 (trans), and the CCBr angle-bending vibrations, 231 cm−1 (gauche) and 190 cm−1 (trans), with dephasing times, 0.45 ps, 0.45 ps, 2 ps, and 1.5 ps, respectively. These vibrational frequencies agree with those obtained in the frequency-domain. That no vibrational mode is observed for C2H4Cl2 might be attributed to ineffective Raman-pumping. Kerr signals observed after the pump-probe overlap are Fourier transformed to give the spectra of the intermolecular motion and the vibrational spectrum, which agrees with the one observed in the infrared absorption and/or Raman scattering heretofore. 相似文献
5.
采用毒性小、环境友好的乙二醇甲醚(ethylene glycol monomethyl ether,EGME)与水混合的双溶剂(体积比为1∶1)溶解CsBr,通过提高CsBr的溶解度,减少了后续CsBr的甲醇溶液的旋涂遍数,简化了电池制备流程。通过优化CsBr的甲醇溶液的旋涂遍数发现,在旋涂1遍200 mg·mL-1 CsBr的水/EGME溶液的基础上旋涂2遍15 mg·mL-1 CsBr的甲醇溶液,所制备的CsPb-Br3钙钛矿太阳能电池(perovskite solar cells,PSCs)拥有最佳的性能,实现了1.44 V的开路电压(open-circuit voltage,VOC),6.26mA·cm-2的短路电流密度(short circuit current density,JSC),74.57%的填充因子(fill factor,FF)及最高6.72%的光电转换效率(pho-toelectric conversion efficiency,PCE)。 相似文献
6.
Yu-Wei Chang Chen-Wei Liu Yu-Chen Wei Kuan-Wen Wang 《Electrochemistry communications》2009,11(11):2161-2164
PtRu/C anode electrocatalysts modified by Sn were prepared for ethanol oxidation reaction (EOR). Their phase structures, surface species, surface compositions, and EOR activities were characterized by XRD, XPS, temperature-programmed reduction (TPR), and CV, respectively. It has been found that in the PtRu/SnxC and PtSn/C alloy catalysts, some Sn alloyed with Pt to form Pt–Sn phase existed as the metallic state, however, the excess Sn existed as the amorphous SnO or crystalline SnO2. Surface analyses and electrochemical measurements suggest that the surface Ru and amorphous SnO instead of the crystalline SnO2 are important species for the promotion of EOR. As a result, compared with PtSn/C, the I06 was enhanced about 200% for the PtRu/C electrocatalyst with 10 wt% of Sn modification. 相似文献
7.
Wei-Ping Chu Jian-Shian Lin Tien-Chai Lin Yu-Sheng Tsai Chen-Wei Kuo Ming-Hua Chung Tsung-Eong Hsieh Lung-Chang Liu Fuh-Shyang Juang Nien-Po Chen 《Optics Communications》2012,285(15):3325-3328
The high haze light-trapping (LT) film offers enhanced scattering of light and is applied to a-Si:H solar cells. UV glue was spin coated on glass, and then the LT pattern was imprinted. Finally, a UV lamp was used to cure the UV glue on the glass. The LT film effectively increased the Haze ratio of glass and decreased the reflectance of a-Si:H solar cells. Therefore, the photon path length was increased to obtain maximum absorption by the absorber layer. High Haze LT film is able to enhance short circuit current density and efficiency of the device, as partial composite film generates broader scattering light, thereby causing shorter wave length light to be absorbed by the P layer so that the short circuit current density decreases. In case of lab-made a-Si:H thin film solar cells with v-shaped LT films, superior optoelectronic performances have been found (Voc = 0.74 V, Jsc = 15.62 mA/cm2, F.F. = 70%, and η = 8.09%). We observed ~ 35% enhancement of the short-circuit current density and ~ 31% enhancement of the conversion efficiency. 相似文献
8.
The Ramanujan Journal - In this paper, we prove two supercongruences conjectured by Sun via the Wilf–Zeilberger method. One of them is, for any prime $$p>3$$ , $$\begin{aligned}... 相似文献
9.
Evolutionary algorithm (EA) has become popular in global optimization with applications widely used in many industrial areas. However, there exists probable premature convergence problem when rugged contour situation is encountered. As to the original genetic algorithm (GA), no matter single population or multi-population cases, the ways to prevent the problem of probable premature convergence are to implement various selection methods, penalty functions and mutation approaches. This work proposes a novel approach to perform very efficient mutation to prevent from premature convergence by introducing the concept of information theory. Information-guided mutation is implemented to several variables, which are selected based on the information entropy derived in this work. The areas of search are also determined on the basis of the information amount obtained from previous searches. Several benchmark problems are solved to show the superiority of this information-guided EA. An industrial scale problem is also presented in this work. 相似文献
10.
Wei-Chun Chen Wei-Ting Chen Yih-Wen Wang Chen-Wei Chiu Chi-Min Shu 《Journal of Thermal Analysis and Calorimetry》2014,118(2):1003-1010
1,1-bis(tert-Butylperoxy)-3,3,5-trimethylcyclohexane (TMCH) is commonly used as a crosslinking agent or an initiator of the heat-curing agent for polybutadiene rubber. Metal ions that remain in the pipelines or containers of manufacturing processes may affect the thermal stability of the organic peroxides. Moreover, pipelines or metal containers may contain some metal ions because of inner corrosive chemicals or surface deterioration, which may induce a chemical reaction, while TMCH is mixed with them. To avoid these unexpected chemical reactions, we focused on the thermal hazard analysis of TMCH mixed with metal ions, such as nickel(II) bromide or copper(II) bromide. The experiments can determine thermokinetic parameters, including exothermic onset temperature (T 0), maximum temperature (T max), and heat of decomposition (ΔH d), under non-isothermal conditions by differential scanning calorimetry. Non-isothermal experimental results combined with isoconversional kinetic analysis can acquire further safety parameters, such as apparent activation energy (E a) and time to maximum heating rate. The results of this study could be used as a proactive case for the storage of TMCH mixed with metal ions. 相似文献