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991.
L LinHui Ye YanLin Jiang DongXing Hua Hui Zheng Tao Li ZhiHuan Ge YuCheng Li XiangQing Lou JianLing Cao ZhongXin Song YuShou Xiao Jun Li QiTe Qiao Rui You HaiBo Chen RuiJiu Xu HuShan Wang JianSong Guo ZhongYan Zhang XueYing Li Chen Hu ZhengGuo Chen RuoFu Wang Meng Xu ZhiGuo Yue Ke Tang Bin Zang YongDong Zhang XueHeng Yao XiangWu Chen JinDa Bai Zhen 《中国科学:物理学 力学 天文学(英文版)》2011,54(1):136-140
Knockout reaction experiment was carried out by using the 6He beams at 61.2 MeV/u impinging on a CH2 target. The α core fragments at forward angles were detected in coincidence with the recoiled protons at larger angles. From this exclusive measurement the valence nucleon knockout mechanism and the core knockout mechanism can be distinguished by the relation between the polar angles of the core fragments and the recoiled protons, respectively. It is demonstrated that the core knockout mechanism may result in some strong contamination to the real invariant mass spectrum.
相似文献992.
High‐Loading Nano‐SnO2 Encapsulated in situ in Three‐Dimensional Rigid Porous Carbon for Superior Lithium‐Ion Batteries 下载免费PDF全文
Hairong Xue Dr. Jianqing Zhao Jing Tang Hao Gong Prof. Ping He Prof. Haoshen Zhou Prof. Yusuke Yamauchi Prof. Jianping He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(14):4915-4923
Tin oxide nanoparticles (SnO2 NPs) have been encapsulated in situ in a three‐dimensional ordered space structure. Within this composite, ordered mesoporous carbon (OMC) acts as a carbon framework showing a desirable ordered mesoporous structure with an average pore size (≈6 nm) and a high surface area (470.3 m2 g?1), and the SnO2 NPs (≈10 nm) are highly loaded (up to 80 wt %) and homogeneously distributed within the OMC matrix. As an anode material for lithium‐ion batteries, a SnO2@OMC composite material can deliver an initial charge capacity of 943 mAh g?1 and retain 68.9 % of the initial capacity after 50 cycles at a current density of 50 mA g?1, even exhibit a capacity of 503 mA h g?1 after 100 cycles at 160 mA g?1. In situ encapsulation of the SnO2 NPs within an OMC framework contributes to a higher capacity and a better cycling stability and rate capability in comparison with bare OMC and OMC ex situ loaded with SnO2 particles (SnO2/OMC). The significantly improved electrochemical performance of the SnO2@OMC composite can be attributed to the multifunctional OMC matrix, which can facilitate electrolyte infiltration, accelerate charge transfer, and lithium‐ion diffusion, and act as a favorable buffer to release reaction strains for lithiation/delithiation of the SnO2 NPs. 相似文献
993.
Gold‐Catalyzed Fluorination–Hydration: Synthesis of α‐Fluorobenzofuranones from 2‐Alkynylphenol Derivatives 下载免费PDF全文
Qiang Wang Yu Jiang Run Sun Prof. Dr. Xiang‐Ying Tang Prof. Dr. Min Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(41):14739-14745
The AuI‐catalyzed fluorination–hydration of 2‐alkynylphenol derivatives in the presence of Selectfluor [1‐chloromethyl‐4‐fluoro‐1,4‐diazoniabicyclo‐[2.2.2]octane bis(tetrafluoroborate)] has been developed. This method provides straightforward access to α‐fluorobenzofuranones with the construction of C?O, C=O, and C?F bonds in a single step on the basis of an AuI/AuIII redox catalytic cycle. Several control experiments, including the asymmetric variant of this reaction, were also conducted to gain insight into the reaction mechanism. 相似文献
994.
Epistasis between cytoplasmic and nuclear genes is the primary genetic component of complex quantitative traits.Genetic dissection of cytonuclear epistasis is fundamentally important to understand the genetic architecture of complex traits.In this study,a two-dimensional genome scan strategy was employed to evaluate the contribution of cytoplasm,quantitative trait loci (QTL),QTL×QTL interactions and QTL×QTL×cytoplasm interactions to the phenotypic variation.The p-value and parameter value for each genetic effect were calculated by multiple regression analysis.A stepwise approach was suggested to build confidence in candidate QTL on the basis of q-value estimation,false discovery rate calculation and Bonferroni adjustment.A fine-scale grid scan strategy was proposed for further analysis of peaks of interest.Plant height in maize was used as an example to illustrate the efficiency of the two-dimensional genome scan strategy. 相似文献
995.
民族主义作为中国近代史上最具广泛感染力与强大推动力的一种社会政治思潮,曾是那个时代各派人物高擎的一面旗帜.作为中国近代民族主义的先行者、实践者,梁启超与孙中山都曾集结在这面旗帜之下,以各自思想所富有的丰富内容、深刻内涵、鲜明特色而影响着当时的民族独立解放运动. 相似文献
996.
997.
通过添加不同含量的稀土元素,对比研究稀土含量对9Cr2Mo钢奥氏体晶粒度、相变点、抗拉强度及耐磨性的影响.研究结果表明,稀土元素可以有效细化9Cr2Mo钢的奥氏体晶粒,当稀土加入量为0.10%时,晶粒长大速率降低最明显.添加质量分数为0.1%的稀土后,9Cr2Mo钢的抗拉强度明显提高,塑性和延展性也有所改善.加入稀土元素后,9Cr2Mo钢在磨损过程中可以避免出现大块疲劳剥落现象,提高了耐磨性. 相似文献
998.
999.
An improved method is proposed to optimize the discrete wavelet decomposition, which can be used to decompose a deformed fringe by easily applying “ridge” information of continuous wavelet transform. With this method the zero component of a deformed fringe pattern can be extracted and eliminated automatically instead of using traditional repetitious tentative experiments. Computer simulations and experiments are carried out to verify our analysis by comparing the results from the correct level selection with that from the adjacent level selection. 相似文献
1000.
为了对自动信任协商(ATN)的安全性进行形式化分析与验证,文中借鉴安全协议的形式化分析方法,提出一种用进程代数Applied π演算对ATN建模并验证其安全性的方法.该方法将ATN形式化为两个协商者进程的并发执行,其中一个协商者的进程就是对其拥有的证书及授权策略的静态建模;ATN的安全性被定义为Applied π演算的观察等价性,从而使该方法不仅能检查授权策略执行的安全性,而且能对协商者的隐私安全进行验证.借助安全协议的自动分析工具ProVerif,文中实现了对ATN安全性的自动分析.实验结果表明,用Applied π演算形式化及验证ATN的安全性是可行的,安全性验证可自动完成,并且效率较高. 相似文献