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β-delayed proton decays near the proton drip line

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2., CHEN Yongshou 2., XU Furong 3., WANG Kun 4 , PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. Institute of Modern Physics, Chinese Academy of sciences, Lanzhou 73.000, China 2. Nuclear Physics department, China Institute of Atomic Energy, {2. 102.13. China 3. department of Technical Physics, peking university, beijing 100871, China 4. Shanghai Institute for Nuclear Research, Shanghai 2.1800, China 1. Institute of Modern Physics Chinese Academy of Sciences 730000 Lanzhou China 2. Nuclear Physics department China Institute of Atomic Energy 102413 Beijing China 3. department of Technical Physics Peking University 100871 Beijing China 4. Shanghai Institute for Nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2.04, namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14 nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92.h as well as the predicted “waiting point” nuclei 89Ru and 93.d are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2. The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 142.o and 12.Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3. The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

Application of Fast Radical Rearrangement in the Mechanistic Investigation of Intramolecular C-H Insertion by Rh(Ⅱ)-Mediated Carbenoids

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Chinese Chemical Letters 1998年第8期9卷 701-704页

作者： Jian Bo WANG Feng Ting LIANG(department of Chemistry, peking university,{2.) department of Chemistry Peking University Beijing 100871 China

In order to investigate the reaction mechanism of intramolecular C-H insertion by Rh(II)-mediated carbenoids with trans-(2.phenylcyclopropyl) carbinal radical as the mechanistic probe, diazo compounds 2.(2.phenylcyclopropyl)ethyl diazoacetoacetate 8a and methyl 2.diazo-3.xo-6-(2.phenylcyclopropyl) hexanoate 8b have been synthesized. Preliminary investigation of the intramolecular C-H insertion with Rh2.OAc)4 as catalyst supports a concerted insertion process.

关键词： Rh(Ⅱ)-mediated carbenoids intramolecular C-H insertion mechanism

Multiuser detection algorithm based on belief propagation in multiple-input multiple-output systems

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Science in China(Series F) 2004年第3期47卷 384-393页

作者： JIANG Wei XIANG Haige department of Electronics, peking university,{2., China 1. department of Electronics Peking University 100871 Beijing China

In MIMO (multiple-input, multiple-output) systems, signals from differenttransmitting antennas interfere at each receiving antenna and multiuser detection (MUD)algorithms may be adopted to improve the system performance. This paper proposes anovel multiuser detection algorithm in MIMO systems based on the idea of 'beliefpropagation' which has achieved great accomplishment in decoding of low-densityparity-check codes. The proposed algorithm has a low computation complexityproportional to the square of transmitting/receiving antenna number. Simulation resultsshow that under low signal-to-noise ratio (SNR) circumstances, the proposed algorithmoutperforms the traditional linear minimum mean square error (MMSE) detector while itencounters a 'floor' of bit error rate under high SNR circumstances. So the proposedalgorithm is applicable to MIMO systems with channel coding and decoding. Although inthis paper the proposed algorithm is derived in MIMO systems, obviously it can be appliedto ordinary code-division multiple access (CDMA) systems.

关键词： multiple-input multiple-output belief propagation multiuser detection

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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Science China Chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU Zhi3. ZHAO Ying2. LING Xiaofeng3. LI Qingbo1, WANG Jiansheng4, ZHANG Nengwei3. ZHANG Yuanfu1 & WU Jinguang1 1. The State Key Laboratory of Rare Earth Materials and Applications, College of Chemistry and Molecular Engineering, peking university, beijing 100871, China 2. Institute of Chemistry, Chinese Academy of {2., {3. 100080, China 3. department of Surgery, Third Hospital, peking university, {3. 100083. China 4. department of Oncology Surgery, the First Hospital of Xi’an Jiaotong university, Xi’an 710061, China Correspondence should be addressed to Wu Jinguang (email: wujg@***) 1. The State Key Laboratory of Rare Earth Materials and Applications College of Chemistry and Molecular Engineering Peking University 100871 Beijing China 2. department of Surgery Third Hospital Peking University 100083 Beijing China 3. Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 4. department of Oncology Surgery the First Hospital of Xi’an Jiaotong University 710061 Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 3. normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 1545 cm-1, a shift of the amide I band to lower wave number, a decrease in the ～1450 cm-1 peak to less than the～1400 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2. which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

SUPERCONDUCTIVITY IN La1.85Sr0.15Cu1-xZnxO4

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低温物理学报 1993年第6期15卷 425-426页

作者： Fusui LiuPhysics department, peking university, {2., {3. 北京大学北京

Based on the multiple exchange-mediated interaction mechanism of high- Tc superconductivity and the Abrikosov-Gorkov theory of magnetic impurity superconductors, this paper quantitatively explains the Zn-substitution ... 详细信息

关键词： Zn SUPERCONDUCTIVITY IN La x)ZnxO4 Cu Sr

Phase relationship of complex multi-component system in chromate cleaner production

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Progress in Natural Science:Materials International 2007年第7期17卷 845-850页

作者： Ge Xinlei~1 Wang Xidong~(1,3.*) Zheng Shili~2.Zhang Mei~1 Zhang Yi~2.(1.department of Physical Chemistry,{2. of Science and Technology {2.,{2. 100083.China 2.Institute of Process Engineering,Chinese Academy of sciences,{2. 100080,China 3.College of Engineering,peking {2.,{2. {12.,China) [a]department of Physical Chemistry University of Science and Technology Beijing Beijing China [b]College of Engineering Peking University Beijing China [c]Institute of Process Engineering Chinese Academy of Sciences Beijing China

The phase relationships of the complex multi-component systems in the liquid-phase oxidization and separation process related with the chromate cleaner production are investigated theoretically and *** phase diagram of main system Fe- Cr2.4-KOH-O2.f oxidization process and the relationship of its standard Gibbs free energy change with temperature are calculated.A se- ries of phase diagrams of the separation process at different temperatures,such as K（Na）OH-K（Na）2.rO4-H2.,KOH-KAlO2.H2., K（Na）OH-K（Na）2.O3.H2.,K（Na）OH-K（Na）HCO3.H2. and K（Na）HCO3.K（Na）2.rO4-H2. have also been *** ex- periments are carried out to verify the calculated *** results showed that the sub-molten salt media are suitable for the oxidization and separation processes;FeCr2.4can be oxidized across a wide range of temperature;K（Na）2.rO4can be separated from K（Na）AlO2.ystem at appropriate temperature and proper concentration;the crystallization of carbonate is easier than that of K（Na）2.rO4.

关键词： chromite chromate system thermodynamics calculation phase diagram

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2.and Li Jianping2.1. College of atmospheric sciences, Lanzhou {2., Lanzhou 73.000, China 2. LASG, Institute of atmospheric Physics, Chinese Academy of sciences, beijing 10002., China) College of atmospheric sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

On　Algebraic　Differential　Equations

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北京大学学报(自然科学版) 1996年第3期 8-24页

作者： CHUANG \ Chitai (department of Mathematics, peking university, {2., {3.)

研究了一般形式的代数微分方程的全纯解的增长性，并证明了几个有关定理。证明是根据一个关于Ｗｉｍａｎ－Ｖａｌｉｒｏｎ理论的定理

关键词：代数微分方程 Wiman-Valiron理论

On the Abundance of Chaotic Behavior for Generic One-Parameter Families of Maps

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Acta Mathematica Sinica,English Series 1996年第4期12卷 398-412页

作者： Zheng Zhiming department of Mathematics peking university {2., {3. China department of Mathematics Peking University Beijing China

In this paper, we want to show the abundance of chaotic systems with absolutely continuous probability measures in the generic regular family with perturbable points. More precisely, we prove that if fa:I→I, a∈P is a regular family satisfying some conditions described in the next section, then there exists a Borel set Ω(?)P of positive Lebesgue measure such that for every a∈Ω, fa admits an absolutely continuous invariant probability measure w.r.t. the Lebesgue measure. The idea of proof in this paper, as compared with that shown in [1] and [7], follows a similar line.

关键词： Chaos Generic regular family Probability measure