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61.
Bean A Gronberg J Kutschke R Menary S Morrison RJ Nelson H Richman J Tajima H Schmidt D Sperka D Witherell M Procario M Yang S Daoudi M Ford WT Johnson DR Lingel K Lohner M Rankin P Smith JG Alexander JP Bebek C Berkelman K Besson D Browder TE Cassel DG Coffman DM Drell PS Ehrlich R Galik RS Garcia-Sciveres M Geiser B Gittelman B Gray SW Hartill DL Heltsley BK Honscheid K Jones C Kandaswamy J Katayama N Kim PC Kreinick DL Ludwig GS Masui J Mevissen J Mistry NB Ng CR Nordberg E O'Grady C 《Physical review letters》1993,70(2):138-142
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Mofakham H Shaabani A Mousavifaraz S Hajishaabanha F Shaabani S Ng SW 《Molecular diversity》2012,16(2):351-356
A novel and efficient method has been developed for the one-pot synthesis of bifunctional diazepine-tetrazole containing compounds. 1H-Tetrazolyl-1H-1,4-diazepine-2, 3-dicarbonitrile and 1H-tetrazolyl-benzo[b][1,4]diazepine derivatives were synthesized in good yields using 2,3-diaminomaleonitrile or an aromatic diamine, ketones, trimethylsilyl azide, and an isocyanide in the presence of p-toluenesulfonic acid as a catalyst in methanol at room temperature. 相似文献
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有监督主成分回归法在近红外光谱定量分析中的应用研究 总被引:5,自引:0,他引:5
介绍了运用有监督主成分回归法建立近红外光谱定量分析模型的原理和方法.利用该方法先进行近红外光谱定量分析建模的波长信息选择,达到降低光谱数据维数的目的,然后建立数学模型,并用其分析预测集样品.文中以66个小麦样品为实验材料,随机选择其中40个样品建立小麦样品中蛋白质含量的近红外光谱定量分析模型,首先优选出4个波长点:4 632,4 636,5 994,5 997 cm-1,利用这4个波长点处光谱信息建立主成分回归模型预测26个样品的蛋白质含量,其结果与凯氏定氮法分析结果的相关系数为0.991,平均相对误差为1.5%.该方法从大量光谱数据中筛选出最重要的部分波长信息,实现了"少而精"的波长点选择,对建立抗共线性信息干扰的光谱定量分析模型,同时对指导专用近红外分析仪器设计中波长点的选择等方面都有一定的意义. 相似文献
66.
Atom localization in a five-level atomic system under the effect of three driving fields and one standing wave field is suggested. A spontaneously emitted photon from the proposed system is measured in a detector. Precision position measurement of an atom is controlled via phase and vacuum field detuning without considering the parity violation. 相似文献
67.
The rare isotope 236U has a half-life of 2.342(3)×107 years,and is produced principally by thermal neutron capture on 235U.The isotopic atom ratio of 236U/238U depends on the integral thermal neutron flux received by the material of interest.236U is potentially useful as a fingerprint for indicating the presence of neutron-irradiated uranium usually originating from nuclear activity.By extracting negative molecular ion UO- from the uranium oxide target,simulating the 236U16O- beam transport with 238U16O- an... 相似文献
68.
Magnetic bunch compressor is one of the key technologies on the path to next generation accelerator driven facilities. In this paper we report the design principles and the first experimental research of the bunch compressor developed at Chinese Academy of Engineering Physics (CAEP). The length of the bunch after compressor is found to be about 0.7 ps (rms) and the peak current exceeds 500 A when operated in the optimized condition. The sensitivity of the bunch length on the phase of the acceleration field and magnetic field of the bunch compressor was also measured and analyzed. 相似文献
69.
Coherent X-ray microscopy has advanced towards higher-energy, more brilliant sources over the past decade since its demonstrations, and many advancements have been made towards optimizing this imaging technique. Here we present both the experimental instrument for obtaining diffraction patterns and the primary reconstruction of yeast cell 2D projection. In addition, the characteristics of the existing optics at BL29XUL of SPring-8 Facility and the method of image reconstruction are discussed. 相似文献
70.
LI ZhiHong SU Jun GUO Bing LI ZhiChang BAI XiXiang LIU JianCheng LI YunJu YAN ShengQuan WANG BaoXiang WANG YouBao LIAN Gang ZENG Sheng LI ErTao CHEN YongShou SHU NengChuan FAN QiWen & LIU WeiPing China Institute of Atomic Energy Beijing China 《中国科学:物理学 力学 天文学(英文版)》2010,(4)
The angular distribution of the 12C(7Li,6He)13N reaction at E(7Li) = 44.0 MeV was measured at the HI-13 tandem accelerator of Beijing, China. The asymptotic normalization coefficient (ANC) of 13N → 12C + p was derived to be (1.64 ± 0.11) fm-1/2 through the distorted wave Born approximation (DWBA) analysis. The ANC was then used to deduce the astrophysical S (E) factors and reaction rates for the 12C(p,γ)13N direct capture reaction at energies of astrophysical relevance. 相似文献