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131.
Na Li Honggang Nie Liping Jiang Guihua Ruan Fuyou Du Huwei Liu 《Journal of separation science》2020,43(15):3146-3163
The structural information and spatial distribution of molecules in biological tissues are closely related to the potential molecular mechanisms of disease origin, transfer, and classification. Ambient ionization mass spectrometry imaging is an effective tool that provides molecular images while describing in situ information of biomolecules in complex samples, in which ionization occurs at atmospheric pressure with the samples being analyzed in the native state. Ambient ionization mass spectrometry imaging can directly analyze tissue samples at a fairly high resolution to obtain molecules in situ information on the tissue surface to identify pathological features associated with a disease, resulting in the wide applications in pharmacy, food science, botanical research, and especially clinical research. Herein, novel ambient ionization techniques, such as techniques based on spray and solid‐liquid extraction, techniques based on plasma desorption, techniques based on laser desorption ablation, and techniques based on acoustic desorption were introduced, and the data processing of ambient ionization mass spectrometry imaging was briefly reviewed. Besides, we also highlight recent applications of this imaging technology in clinical researches and discuss the challenges in this imaging technology and the perspectives on the future of the clinical research. 相似文献
132.
Nonlinear Dynamics - Hysteresis is an inherent characteristic of piezoelectric materials that can be determined by not only the historical input but also the input signal frequency. Hysteresis... 相似文献
133.
综合性、设计性实验教学的探讨 总被引:1,自引:0,他引:1
综合性、设计性实验是培养学生的创新意识、创新精神和创新能力的有效措施;本文就开设综合性、设计性实验的意义、内涵、与基础实验的关系以及如何设计项目内容进行了初步的探讨。 相似文献
134.
Feng Wenjie Nie Hui Han Xu 《Acta Mechanica Solida Sinica》2007,20(3):275-282
This paper analyzes the dynamic magnetoelectroelastic behavior induced by a penny- shaped crack in a magnetoelectroelastic layer.The crack surfaces are subjected to only radial shear impact loading.The Laplace and Hankel transform techniques are employed to reduce the prob- lem to solving a Fredholm integral equation.The dynamic stress intensity factor is obtained and numerically calculated for different layer heights.And the corresponding static solution is given by simple analysis.It is seen that the dynamic stress intensity factor for cracks in a magnetoelec- troelastic layer has the same expression as that in a purely elastic material.And the influences of layer height on both the dynamic and static stress intensity factors are insignificant as h/a>2. 相似文献
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The purpose of this paper is to consider the expected value of a discounted penalty due at ruin in the Erlang(2) risk process under constant interest force. An integro-differential equation satisfied by the expected value and a second-order differential equation for the Laplace transform of the expected value are derived. In addition, the paper will present the recursive algorithm for the joint distribution of the surplus immediately before ruin and the deficit at ruin. Finally, by the differential equation, the defective renewal equation and the explicit expression for the expected value are given in the interest-free case. 相似文献
138.
制备高质量的MgB2薄膜是实现MgB2超导电子器件应用的前提和基础.我们用电子束蒸发B膜和Mg/B多层膜为前驱然后后退火的方法,分别在高温区(~900℃)和中温区(~750℃)成功获得了MgB2超导薄膜.改变退火的Ar气压条件,采用B膜前驱退火的样品Tc可达到38K以上,转变宽度0.3K.Mg/B多层膜的结果尽管Tc稍低(Tc~35K),但薄膜表面更加均匀,且避免了高温下Mg蒸汽污染的问题.对于两种前驱退火中观察到的完全不同的退火气压影响,我们认为是与其各自的超导成相过程相联系的,在此基础上我们对退火气压效应给出了自己的分析和解释,为今后进一步细致研究退火过程中的薄膜生长机制提供了参考. 相似文献
139.
Zhao Wei Xinlei Zhang Huifang Nie Lin Yao Yanqin Liu Zhibing Zheng Qin Ouyang 《Molecules (Basel, Switzerland)》2022,27(3)
A family of novel efficient non-oxime compounds exhibited promising reactivation efficacy for VX and sarin inhibited human acetylcholinesterase was discovered. It was found that aromatic groups coupled to Mannich phenols and the introduction of imidazole to the ortho position of phenols would dramatically enhance reactivation efficiency. Moreover, the in vivo experiment was conducted, and the results demonstrated that Mannich phenol L10R1 (30 mg/kg, ip) could afford 100% 48 h survival for mice of 2*LD50 sarin exposure, which is promising for the development of non-oxime reactivators with central efficiency. 相似文献
140.
建立了戊四硝酯粉含量及有关物质的RP-HPLC测定法。采用ODS色谱柱,甲醇/水(70∶30)为流动相,使戊四硝酯与有关物质基线分离,二极管阵列检测器检测波长206nm。本方法操作简便,重现性好。 相似文献