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101.
化爆冲击波和炮口冲击波对生物致伤效应的对比研究 总被引:1,自引:0,他引:1
通过TNT化爆和火炮现场试验,探讨了化爆冲击波和炮口冲击波的异同点,结果发现两者的频谱大致相似。但化爆冲击波只有一次激波,而炮口冲击波有两次激波,有时甚至可见到三次激波。生物效应致伤的靶器官也有所不同,化爆冲击波以肺损伤较为多见,而炮口冲击波似乎以上呼吸道更为敏感,结果提示化爆可以模拟炮口冲击波,但又不完全等同于炮口冲击波,必要的火炮现场试验是必不可少的。 相似文献
102.
使用不同的方法来确定La Br3晶体信号的到达时间。在文中信号经过光电倍增管的放大之后由DSR4测试板进行数字采集,其中DRS4是由瑞士PSI研究所生产的高带宽、低功耗以及快读出时间的开关电容阵列。这些优势使得DRS4很具有吸引力,很多实验将传统的ADC与TDC替换为DRS4。采集的波形可以通过不同的方法进行后续处理。其中包括:(1)恒分甄别、(2)波形拟合、(3)PMT脉冲模型法以及(4)均值过滤法。文中实现的恒分甄别的时间分辨与使用模拟电路获取的平均时间分辨相比没有提高。高斯波形拟合法虽然与数字CFD的结果相当,但是却更加耗时。均值滤波法虽然容易实现,但是通过这个方法得到的时间分辨与采样时间在一个量级。而PMT脉冲模型法得到的平均时间分辨为195.4 ps,优于模拟信号的恒分甄别的时间分辨254.7 ps。 相似文献
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105.
Wei Sun Ling Zhang Ruifeng Yang Chen Shao Zhengguo Zhang Youhe Gao 《Rapid communications in mass spectrometry : RCM》2009,23(1):109-118
Peptide retention time (RT) is independent of tandem mass spectrometry (MS/MS) parameters and can be combined with MS/MS information to enhance peptide identification. In this paper, we utilized peptide empirical RT and MS/MS for peptide identification. This new approach resulted in the construction of an Empirical Peptide Retention Time Database (EPRTD) based on peptides showing a false‐positive rate (FPR) ≤1%, detected in several liquid chromatography (LC)/MS/MS analyses. In subsequent experiments, the RT of peptides with FPR >1% was compared with empirical data derived from the EPRTD. If the experimental RT was within a specified time range of the empirical value, the corresponding MS/MS spectra were accepted as positive. Application of the EPRTD approach to simple samples (known protein mixtures) and complex samples (human urinary proteome) revealed that this method could significantly enhance peptide identification without compromising the associated confidence levels. Further analysis indicated that the EPRTD approach could improve low‐abundance peptides and with the expansion of the EPRTD the number of peptide identifications will be increased. This approach is suitable for large‐scale clinical proteomics research, in which tens of LC/MS/MS analyses are run for different samples with similar components. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
106.
Yaochen Zheng Peng Song Shaoxiang Liu Mengqing Wu Hui Xu Chenghui Qiao Jian Liu Zhengguo Gao Qingfu Ban 《Journal of polymer science. Part A, Polymer chemistry》2021,59(13):1390-1398
Spiroacetal moieties containing linear telechelic polymers (LTPs) with two terminal epoxy groups were facilely synthesized via the successive thiol-ene and thiol-epoxy click additions. The LTPs were incorporated into epoxy matrix to fabricate the transparent and toughening thermosets. In term of the miscibility of epoxy with the adduct of ethanedithiol and 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane (BTU), it is proposed that the size of the formed nanostructures was small enough to allow light penetrate. Therefore, the modified thermosets were transparent, which was further confirmed by small-angle X-ray scattering (SAXS) measurements. The LTPs with an alternating structure of rigid spiroacetal moiety and soft thioether could formed heterogeneous crosslinked networks (HCNs) and obviously toughen epoxy thermosets. Flexural strength increased from 1.06 GPa for neat epoxy to 2.09 GPa for toughening thermosets modified with 15 wt% LTPs. The stress field intensity (KIC) value reached up to 3.93 by more than 125% compared with that of the control sample (1.75). This work uncovered the role of HCNs on performance and paved a way for technological advances toward transparent and toughening materials in epoxy thermosets. 相似文献
107.
白正国 《浙江大学学报(理学版)》1990,(1)
关于紧的黎曼流形中的Killing张量场,已有若干研究,例如Mogi,Yano,Bochner,Hsiung,C.C.等.后者把前人一些结果推广到带边的紧的流形去,本文把熊的一些结果再加以改进.即不限于流形的边而对紧的黎曼流形中的某些超曲面进行研究.最后把所得结果应用到拟常曲率流形,得出相应的结论. 相似文献
108.
Tong Yang Xiao Zuo Du Xiaoyan Zuo Chuantian Li Yuelong Lv Menglan Yuan Yongbo Yi Chenyi Hao Feng Hua Yong Lei Ting Lin Qianqian Sun Kuan Zhao Dewei Duan Chunhui Shao Xiangfeng Li Wei Yip Hin-Lap Xiao Zhengguo Zhang Bin Bian Qingzhen Cheng Yuanhang Liu Shengjian Cheng Ming Jin Zhiwen Yang Shangfeng Ding Liming 《中国科学:化学(英文版)》2020,63(6):758-765
Organic solar cells have attracted academic and industrial interests due to the advantages like lightweight, flexibility and roll-to-roll fabrication. Nowadays, 18% power conversion efficiency has been achieved in the state-of-the-art organic solar cells. The recent rapid progress in organic solar cells relies on the continuously emerging new materials and device fabrication technologies, and the deep understanding on film morphology, molecular packing and device physics. Donor and acceptor materials are the key materials for organic solar cells since they determine the device performance. The past 25 years have witnessed an odyssey in developing high-performance donors and acceptors. In this review, we focus on those star materials and milestone work, and introduce the molecular structure evolution of key materials. These key materials include homopolymer donors, D-A copolymer donors, A-D-A small molecular donors, fullerene acceptors and nonfullerene acceptors. At last, we outlook the challenges and very important directions in key materials development. 相似文献
109.
Nonlinear Dynamics - This paper pays close attention to the problem of energy-to-peak state estimation for a class of neural networks under switching mechanism. Persistent dwell-time switching... 相似文献
110.
Shushan Ge Jihui Li Yu Yu Zhengguo Chen Yi Yang Liqing Zhu Shibiao Sang Shengming Deng 《Molecules (Basel, Switzerland)》2021,26(21)
As the most frequently occurring cancer worldwide, breast cancer (BC) is the leading cause of cancer-related death in women. The overexpression of HER2 (human epidermal growth factor receptor 2) is found in about 15% of BC patients, and it is often associated with a poor prognosis due to the effect on cell proliferation, migration, invasion, and survival. As a result of the heterogeneity of BC, molecular imaging with HER2 probes can non-invasively, in real time, and quantitatively reflect the expression status of HER2 in tumors. This will provide a new approach for patients to choose treatment options and monitor treatment response. Furthermore, radionuclide molecular imaging has the potential of repetitive measurements, and it can help solve the problem of heterogeneous expression and conversion of HER2 status during disease progression or treatment. Different imaging probes of targeting proteins, such as monoclonal antibodies, antibody fragments, nanobodies, and affibodies, are currently in preclinical and clinical development. Moreover, in recent years, HER2-specific peptides have been widely developed for molecular imaging techniques for HER2-positive cancers. This article summarized different types of molecular probes targeting HER2 used in current clinical applications and the developmental trend of some HER2-specific peptides. 相似文献