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91.
Solid‐state Li metal batteries (SSLMBs) have attracted considerable interests due to their promising energy density as well as high safety. However, the realization of a well‐matched Li metal/solid‐state electrolyte (SSE) interface remains challenging. Herein, we report g‐C3N4 as a new interface enabler. We discover that introducing g‐C3N4 into Li metal can not only convert the Li metal/garnet‐type SSE interface from point contact to intimate contact but also greatly enhance the capability to suppress the dendritic Li formation because of the greatly enhanced viscosity, decreased surface tension of molten Li, and the in situ formation of Li3N at the interface. Thus, the resulting Li‐C3N4|SSE|Li‐C3N4 symmetric cell gives a significantly low interfacial resistance of 11 Ω cm2 and a high critical current density (CCD) of 1500 μA cm?2. In contrast, the same symmetric cell configuration with pristine Li metal electrodes has a much larger interfacial resistance (428 Ω cm2) and a much lower CCD (50 μA cm?2).  相似文献   
92.
1,3-偶极环加成合成双-1,2,4-噁二唑啉衍生物及单晶结构   总被引:1,自引:0,他引:1  
2-苯基-1,2,3-三唑基-4-甲醛与1,3-丙二胺或对苯二胺缩合, 形成新的双席夫碱3和4, 然后分别与氯代肟在三乙胺条件下发生1,3-偶极环加成, 得到新型双-1,2,4-噁二唑衍生物6a~6f和7a~7f. 结构经元素分析, IR, 1H NMR和MS确证, 并用X射线衍射法测定了化合物6e的晶体结构. 化合物6e属于单斜晶系, C2/c空间群, 晶胞参数 a=3.5134(8) nm, b=0.50575(11) nm, c=2.0598(5) nm, α=90°, β=102.02(8)°, γ=90°, Mr=756.81, V=3.5798(14) nm3, Dc=1.404 g/cm3, Z=4, F(000)=1576, μ=0.095 mm-1, R=0.0787, wR=0.2093.  相似文献   
93.
在模拟生理条件下,采用荧光光谱法、圆二色光谱法和红外光谱法研究了花椒油素(XT)与牛血清白蛋白(BSA)的相互作用。结果表明花椒油素与牛血清白蛋白之间发生动态和静态联合猝灭,二者间的的猝灭常数(K)在286, 298和310 K分别为3.31 × 105, 到2.03 × 105 和 0.94 × 105 L∙mol-1. 热力学参数表明, 花椒油素与牛血清白蛋白间以疏水作用力为主。圆二色光谱和红外光谱法表明加入花椒油素后,牛血清白蛋白的二级结构发生了变化,其中α-螺旋减少了3.9%。另外,我们还研究了共存离子对两者结合的影响。  相似文献   
94.
Solid‐state NMR is a powerful tool for studying membrane proteins in a native‐like lipid environment. 3D magic angle spinning (MAS) NMR was employed to characterize the structure of E.coli diacylglycerol kinase (DAGK) reconstituted into its native E.coli lipid membranes. The secondary structure and topology of DAGK revealed by solid‐state NMR are different from those determined by solution‐state NMR and X‐ray crystallography. This study provides a good example for demonstrating the influence of membrane environments on the structure of membrane proteins.  相似文献   
95.
吸附剂负载TiO2光催化研究进展   总被引:5,自引:1,他引:5  
TiO2光催化在废水处理、空气净化等环保领域展示出诱人前景.纳米TiO2光催化剂的负载化是实现其产业化的关键步骤之一.多孔吸附剂与纳米TiO2复合可提供对污染物的高浓度吸附环境,提高TiO2分散度,解决催化剂分离难题,是光催化领域的研究热点之一.本文对近年来国内外多孔吸附剂与纳米TiO2复合的发展情况进行了综述,着重介绍了负载型TiO2光催化剂的固定化方法、多孔吸附剂类型以及负载对光催化活性的影响机理.  相似文献   
96.
提出通过离子-电子非平衡物理模型来降低惯性约束聚变中心热斑点火的聚变点火条件。在该物理模型中,强调离子比电子具备更高的温度,从而使得热斑的热核聚变反应增强,轫致辐射和电子热传导造成的能量漏失相对降低。通过对中心热斑的自加热分析和热斑燃烧动力学分析,发现相对于平衡聚变点火模型,非平衡模型可以显著扩大聚变点火区在热斑面密度和热斑温度空间的范围。同时采用LARED-S程序的数值模拟,研究了通过尖峰脉冲波形、二次冲击物理机制强化中心热斑聚变点火的非平衡性。  相似文献   
97.
介绍了一种基于常规速调管功率合成和脉冲压缩的微波源系统,为实现多路高峰值功率速调管的功率合成,设计了一种紧凑型、近平面结构的微波功率合成器。在2.856 GHz频点处,合成器各端口反射损耗和相对端口隔离度均大于45 dB。当两路峰值功率为50 MW的微波功率合成时,合成器内的最大场强约为9.6 MV/m,合成效率大于99%。在四端口功率合成器的基础上,通过两级合成可实现一种八端口微波功率合成器,当四路峰值功率50 MW的微波功率合成时,合成器内最大场强约为13.5 MV/m。  相似文献   
98.
Gao  Zhengfeng  Gao  Heqi  Zheng  Debin  Xu  Tengyan  Chen  Yaoxia  Liang  Chunhui  Wang  Ling  Ding  Dan  Yang  Zhimou 《中国科学:化学(英文版)》2020,63(3):398-403
The selective identification and removal of senescent cells including senescent cancer cells are very important to prolong life and improve the treatment efficacy of cancer therapy.In this study,we integrated the high selectivity of enzyme-instructed selfassembly(EISA) and efficient reactive oxygen species(ROS) generating property of a novel luminogen with aggregationinduced emission(AIE) character to selectively identify and remove senescent He La(s-He La) cells.The s-He La cells expressed high levels of β-galactosidase(β-Gal),which led to the selective accumulation and formation of nanomaterials of Comp.1 in the cells.Upon white light irradiation,the nanomaterials efficiently produced ROS and therefore killed s-He La cells.Our study demonstrated a promising strategy to selectively remove senescent cells and improve the treatment efficacy of cancer therapy.  相似文献   
99.
High contrast transparent Ramsey fringes are observed using double microwave pulses interaction with the prepared atomic coherent state in a warm 87Rb vapor with mixture buffer gases in a closed cell. The Ramsey fringes are generated by the pulsed technique, a strong coupling light pulse and a weak signal light pulse are applied to prepare the atomic coherent state, followed by the application of double microwave pulses to interact with the atomic coherent state. Afterwards, the light pulses are applied again with weaker intensity and detecting the signal transmission is delected. The central line of the transparent Ramsey fringes has narrow linewidth of 125 Hz and high contrast of 21%. The light shift is dramatically reduced since the interrogating process is not involved the light field, and the cavity pulling effect is negligible due to the low Q requirement, which is promising for building small, compact, and stable atomic clocks.  相似文献   
100.
Based on our previous study on the elementary characterization of fuzzy symmetry, we inquire into the fuzzy symmetries of some simple linear and plane molecules. These systems belong to point groups that include the identity and twofold symmetry elements, but not include higher multi-fold symmetry ones, and their molecular orbitals (MOs) only belong to one-dimension irreducible representations. In this paper, we take the azines as a typical model to examine the fuzzy symmetry in relation to the D6h point group. As this group includes multi-fold symmetry elements such as a sixfold rotation axis, some of the MOs may belong to two-dimensional irreducible representations. We inquire into the fuzzy symmetry of these molecules and their MOs in terms of membership functions, representation components and correlation diagrams. In addition to these neutral closed shell molecules, pyridine hydride radical, anion, and cation are also analyzed.  相似文献   
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