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241.
The large interfacial resistance seriously restricts the development of all-solid-state lithium batteries (ASSLBs). In our work, first-principles calculations are employed to investigate the interfacial properties on lithium (Li) metal anode/Li6PS5Cl solid electrolyte (LPSCl) interface system as well as buffer layers (Li2S) effects. The stable interface structures, Li/LPSCl, L2S/LPSCl and Li/L2S, are established at atomic level. We find that PS4 tetrahedral structure has been seriously destroyed in Li/LPSCl interface, whereas the presence of Li2S buffer layers may smooth the interface without PS4 tetrahedral damage occurred. In addition, the electronic structure of interface indicates that solid electrolyte interphases are not easy to form on LPSCl surfaces considering buffer layers effects, which may improve the stability of anode/solid electrode interface. Moreover, the calculated energies of exchange ions between Li metal and solid electrolyte with buffer layers suggest that the Li2S interposition can suppress the atoms diffusion in LPSCl layers, and provide a smooth interface structure, which may promote the stability of Li/LPSCl interface. This work on the atomic scale will offer a useful perspective for designing high performance of solid electrolytes to enhance good cyclability in ASSLBs.  相似文献   
242.
固定化酶反应器作为蛋白质组学研究中"bottom-up"策略重要的组件,具有酶解快速、酶解效率高、酶稳定性和活性高、简单易操作、能够与多种检测方式联用等优点,对于发展高效快速的蛋白质组学分析方法具有重要意义。本文就固定化酶反应器的制备方法及其在蛋白质组学中的应用做简单的概述,着重介绍酶的固定方法、固定化酶的载体、用于固定的酶的种类。近几年固定化酶反应器的研究集中于提高固酶量、保持酶活性、增加酶解效率、减小非特异性吸附等方面。研究结果表明,采用纳米材料、整体材料等新型载体,提高载体亲水性,采用多酶同时酶解等方法能够有效改善固定化酶反应器的性能,提高蛋白质的鉴定效率。  相似文献   
243.
曾秉斌  徐德衍 《光学学报》1995,15(5):23-627
在研究了激光光束质量因子M^2理论及测量技术基础上,作者提出了一种新的用干涉测量光束质量因子M^2的理论,技术与方法。文中概述了该技术的理论基础、实验结果及误差分析。结果表明,该方法具有精度高,适用性强,测量简便等优点,有可能进一步仪器化并推广应用。  相似文献   
244.
许兵兵  李晓敏  张庆合  朱维晃 《色谱》2018,36(8):786-794
建立了气相色谱-串联质谱(GC-MS/MS)测定复杂基体婴儿奶粉中16种邻苯二甲酸酯类塑化剂的分析方法。奶粉样品以水溶解均质,乙腈提取,乙二胺-N-丙基硅烷(PSA)类型玻璃固相萃取柱净化,DB-5 MS UI气相色谱柱(30 m×0.25 mm×0.25 μm)分离,同位素稀释质谱法(IDMS)定量。比较了氧化铝/PSA和PSA两种固相萃取柱在不同洗脱条件下萃取16种塑化剂的回收率。最终选择PSA固相萃取柱,以正己烷-丙酮(60:40,v/v)作为洗脱溶剂,实现奶粉基体中16种塑化剂的净化。采用基质匹配同位素内标法定量,16种塑化剂在0.01~2.0 mg/kg范围内线性良好,线性相关系数(R2)大于0.9996,检出限和定量限分别是0.15~2.50 μg/kg和0.50~8.33 μg/kg,加标回收率为96.1%~104.0%,相对标准偏差(RSD)小于3.3%(n=5),该方法灵敏度好、精密度高,适用于婴儿奶粉基体中16种塑化剂的痕量分析。  相似文献   
245.
The contradiction between the rising demands of optical chirality sensing and the failure in chiral detection of cryptochiral compounds encourages researchers to find new methods for chirality amplification. Inspired by planar chirality and the host–guest recognition of pillararenes, we establish a new concept for amplifying CD signals of cryptochiral molecules by pillararene host–guest complexation induced chirality amplification. The planar chirality of pillararenes is induced and stabilized in the presence of the chiral guest, which makes the cryptochiral molecule detectable by CD spectroscopy. Several chiral guests are selected in these experiments and the mechanism of chiral amplification is studied with a non‐rotatable pillararene derivative and density functional theory calculations. We believe this work affords deeper understanding of chirality and provides a new perspective for chiral sensing.  相似文献   
246.
GridMol is a “one-stop” platform for molecular structure building, scientific computing, and molecular visualization aided by a high-performance computing environment. GridMol version 2.0 introduces two unique features: the first is fragment-based linear-scaling quantum chemistry methods, such as molecular fractionation with conjugate caps and fragment molecular orbital methods; the second is that GridMol enables users to visualize molecular geometries along a geometry optimization and an intrinsic reaction coordinate calculation. Compared with version 1.0, fragment-based linear-scaling quantum chemistry methods implemented in GridMol version 2.0 can be used as a useful tool for performing quantum calculations for large molecular systems to explore the mechanisms involved in protein-ligand or targeted drug interactions.  相似文献   
247.
The first high pressure study of solid hydrazinium monochloride has been performed by in situ Raman spectroscopy and synchrotron X‐ray diffraction (XRD) experiments in diamond anvil cell (DAC) up to 39.5 and 24.6 GPa, respectively. The structure of phase I at room temperature is confirmed to be space group C2/c by the Raman spectral analysis and Rietveld refinement of the XRD pattern. A structural transition from phase I to II is observed at 7.3 GPa. Pressure‐induced position variation of hydrogen atoms in NH3+ unit during the phase transition is attributed to the formation of N―H…Cl hydrogen‐bonds, which play a vital role in the stability and subsequent structural changes of this high energetic material under pressure. This inference is proved from the abnormal pressure shifts and obvious Fermi resonance in NH stretching mode of N2H5+ ion in the Raman experiment. Finally, a further transition from phase II to III accompanied with a slight internal distortion in the N2H5+ ions occurs above 19.8 GPa, and phase III persists up to 39.5 GPa. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
248.
This paper reports the use of polyhedral oligomeric silsesquioxane (POSS)‐based copolymers to stabilize the core/shell interface for the facile fabrication of electrospun core/shell fibers. For the poly[(propylmethacryl‐heptaisobutyl‐polyhedral oligomeric silsesquioxane)‐co‐(methyl methacrylate)] (POSS‐MMA)/poly(ε‐caprolactone) (PCL) system, the bicontinuity of hybrid core/shell fibers can be tuned by controlling the phase separation of POSS‐MMA/PCL in electrospinning solutions and therefore the size of PCL‐in‐POSS‐MMA emulsion droplets. Our results demonstrate the enhanced encapsulation capacity of POSS‐MMA copolymers as shell materials. Taking advantage of the rapid advancement of POSS‐based copolymer synthesis, this study can potentially be generalized to guide the fabrication of various other POSS‐based core/shell nano‐/microstructures by using single‐nozzle electrospinning or coaxial electrospinning.

  相似文献   

249.
In this paper, we propose a novel optimal sensitivity design scheme for the yarn tension sensor using surface acoustic wave (SAW) device. In order to obtain the best sensitivity, the regression model between the size of the SAW yarn tension sensor substrate and the sensitivity of the SAW yarn tension sensor was established using the least square method. The model was validated too. Through analyzing the correspondence between the regression function monotonicity and its partial derivative sign, the effect of the SAW yarn tension sensor substrate size on the sensitivity of the SAW yarn tension sensor was investigated. Based on the regression model, a linear programming model was established to gain the optimal sensitivity of the SAW yarn tension sensor. The linear programming result shows that the maximum sensitivity will be achieved when the SAW yarn tension sensor substrate length is equal to 15 mm and its width is equal to 3 mm within a fixed interval of the substrate size. An experiment of SAW yarn tension sensor about 15 mm long and 3 mm wide was presented. Experimental results show that the maximum sensitivity 1982.39 Hz/g was accomplished, which confirms that the optimal sensitivity design scheme is useful and effective.  相似文献   
250.
Nano-layered sorbents for CO(2) capture, for the first time, were developed using layer-by-layer nanoassembly. A CO(2)-adsorbing polymer and a strong polyelectrolyte were alternately immobilized within porous particles. The developed sorbents had fast CO(2) adsorption and desorption properties and their CO(2) capture capacity increased with increasing nano-layers of the CO(2)-adsorbing polymer.  相似文献   
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