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Nonlinear optical properties and superluminal propagation in the ruby

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Chinese science Bulletin 2010年第6期55卷 473-477页

作者： GAO Feng1,2.3,XU JingJun1,2.3,ZHANG GuoQuan1,2.3 & ZHANG WenDing1,2.3 1 Photonics center,College of Physics science,Nankai University,Tianjin 300457,{2. 2.The Key laboratory of Advanced Technique and Fabrication for Weak-Light Nonlinear Photonics Materials of Ministry of Education,Nankai University,Tianjin 300457,{2. 3 Tianjin Key laboratory of Photonics Materials and technology for information science,Nankai University,Tianjin 300457,{2. Photonics center College of Physics Science Nankai University Tianjin 300457 China Key laboratory of Advanced Technique and Fabrication for Weak-Light Nonlinear Photonics Materials of Ministry of Education Nankai University Tianjin 300457 China Tianjin Key laboratory of Photonics Materials and technology for {2. science Nankai University Tianjin 300457 China

In this review article,we summarized the study of the weak light nonlinear properties associated with group velocity change in the *** ruby could be reduced to a two-level system,in which population oscillations could lead to a subluminal *** the modulated TEM00 beam introduced into the ruby,self-phase modulation together with Fraunhofer diffractions and nondegenerate two-wave coupling between different spatial frequency components of the beam occurs at the same *** oscillations,self-phase modulation together with Fraunhofer diffractions and nondegenerate two-wave coupling mechanism competes with each other,which brings a new phenomenon of self-superluminal group velocity propagation in the ruby.

关键词：非线性光学性质超光速传播红宝石自相位调制 TEM00模速度变化光束耦合空间频率

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2. CUI Yuezhi3, HUANG Zhenli4, XUE Gang1 & YU Wentao1 1. State Key laboratory of Crystal Materials, Shandong University, Jinan 2.0100, china 2. School of {2. science and Engineering, Shandong University, Jinan 2.0100, china 3. Department of Chemical Engineering, Light Industry College of Shandong, Jinan 2.0100, china 4. Key laboratory of Biomedical Photonics, Ministry of Education, Huazhong University of science and technology, Wuhan 430074, china 1. State Key laboratory of Crystal Materials Shandong University 250100 Jinan China 2. School of information science and Engineering Shandong University 250100 Jinan China 3. Department of Chemical Engineering Light Industry College of Shandong 250100 Jinan China 4. Key laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2.4-dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2.4-dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2.methyl-4,6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2.. NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064 nm fundamental laser, NEt-1 powder crystals radiate a 2.order harmonic light with an intensity 46.8 times that of urea. The Λ typed NMe-2.molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P2. space group. Its powder crystals exhibit a 2.order harmonic intensity 46.2.times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2.order nonlinear optical (NLO) efficiency on the micro 2.order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

Lunar surface dielectric constant,regolith thickness, and ~3He abundance distributions retrieved from the microwave brightness temperatures of CE-1 Lunar Microwave Sounder

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science china Earth sciences 2010年第9期53卷 1365-1378页

作者： WANG ZhenZhan1, LI Yun1,2. JIANG JingShan1 & LI DiHui1 1 national Microwave Remote Sensing laboratory, {2. for Space science and Applied Research, Chinese Academy of sciences, beijing 100190, china 2.Graduate University of Chinese Academy of sciences, beijing 100049, china 1. national Microwave Remote Sensing laboratory Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Lunar regolith parameters, such as physical temperature, thickness and dielectric constant, are important in studying regolith features, distribution of lunar resources and evolution of the Moon. There had been no measurement obtained by lunar-orbit-borne microwave radiometer applied to evaluate the properties of lunar regolith before CE-1 Lunar Microwave Sounder (CELMS) being launched. CEMLS is the first passive microwave radiometer in the world to sound the surface of the Moon. The brightness temperatures (TB) sensed by CELMS include complicated information on the above geophysical parameters. In this paper, algorithms of retrieving dielectric constant, regolith thickness, and 3He content from CELMS brightness temperatures are developed, and the results are compared with those from literature. The results show that the regolith thicknesses are mostly in the range of 4.0-6.0 m, and 43% of them are bigger than 5.0 m. The content of 3He evaluated by retrieved regolith thickness is about 1.03 million tons.

关键词： CE-1 Lunar Microwave Sounder (CELMS) lunar regolith dielectric constant lunar regolith thickness 3He retrieval

quantum secret sharing between m-party and n-party with six states

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science china(Physics,Mechanics & Astronomy) 2009年第8期52卷 1191-1202页

作者： GAO Ting1,YAN FengLi2.3 & LI YouCheng2.3 1 College of Mathematics and information science,Hebei Normal University,Shijiazhuang 050016,{2. 2.College of Physics and information Engineering,Hebei Normal University,Shijiazhuang 050016,{2. 3 Hebei Advanced Thin Films laboratory,Shijiazhuang 050016,{2. College of Mathematics and information science Hebei Normal University Shijiazhuang 050016 China College of Physics and information Engineering Hebei Normal University Shijiazhuang 050016 China Hebei Advanced Thin Films laboratory Shijiazhuang 050016 China

A quantum secret sharing scheme between an m-party group and an n-party group is proposed using three conjugate bases.A sequence of single photons,each of which is prepared in one of the six states,is used directly to encode classical information in the quantum secret sharing *** this scheme,each of all m members in group 1 chooses randomly his/her own secret key individually and independently,and directly encodes his/her respective secret information on the states of single photons via unitary operations,then the last one sends 1/n of the resulting qubits to each member of group *** measuring their respective qubits,all members in group 2.share the secret information shared by all members in group *** renders impossible a Trojan horse attack with a multi-photon signal,a fake-signal attack with EPR pairs,an attack with single photons,and an attack with invisible *** give the upper bounds on the average success probabilities for dishonest agent eavesdropping encryption using the fake-signal attack with any two-particle entangled states.

关键词： quantum secret sharing security EPR pairs

Complete multiple round quantum dense coding with quantum logical network

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Chinese science Bulletin 2007年第9期52卷 1162-1165页

作者： LI ChunYan1,2.LI XiHan1,2.DENG FuGuo1,2.3,ZHOU Ping1,2.& ZHOU HongYu1,2.3 1 Key laboratory of Beam technology and Material Modification of Ministry of Education,{2. Normal University,{2. 100875,china 2.Institute of Low Energy Nuclear Physics,and Department of Material science and Engineering,{2. Normal University,{2. 100875,china 3 {2. Radiation center,{2. 100875,china Key laboratory of Beam technology and Material Modification of Ministry ofEducation Beijing Normal University Beijing 100875 China

We present a complete multiple round quantum dense coding scheme for improving the source ca-pacity of that introduced recently by Zhang et al. The receiver resorts to two qubits for storing the four local unitary ope... 详细信息

关键词：量子通信多重量子紧凑编码量子逻辑网络量子纠缠

Reverse reconciliation for continuous variable quantum key distribution

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 100-105页

作者： LU ZhiXin 1,2., YU Li 1,2., LI Kang 1,2., LIU BingCan 1,2.3 , LIN JianGui 1,2., JIAO RongZhen 1,2.& YANG BoJun 1,2. School of science, beijing University of Posts and Telecommunications, beijing 100876, china 2.Key laboratory of information Photonics and Optical Communication, Ministry of Education, beijing University of Posts and Telecommunications, beijing 100876, china 3 Department of Fundamental Courses, Academy of Armored Force Engineering, beijing 100072. china 1. School of science Beijing University of Posts and Telecommunications Beijing 100876 China2. Key Laboratory of Information Photonics and Optical Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China3. Department of Fundamental Courses Academy of Armored Force Engineering Beijing 100072 China

An efficient and practical post-processing technique based on reverse reconciliation for continuous variable quantum key distribution is proposed and simulated with low-density parity check (LDPC) codes. MultiLevel Coding/ MultiStage Decoding, which fully utilizes optimization technique such as vector quantization and iterative decoding and the optimal channel coding most close to the Shannon limit, was used to realize efficient reverse reconciliation algorithm. Simulation results showed that the proposed method can improve the secure key distribution rate to 2.2.kb/s and the coding efficiency to 0.89 over 2. km in single-mode optical fiber. Moreover, there still is room for much improvement.

关键词： quantum communication key distribution reverses reconciliation low-density parity check codes

Association between ICU quality and in-hospital mortality of V-V ECMO-supported patients—the ECMO quality improvement action(EQIA)study:a national cohort study in china from 2.17 to 2.19

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Frontiers of Medicine 2024年第2期18卷 315-326页

作者： Wei Cheng Jieqing Chen Xudong Ma Jialu Sun Sifa Gao Ye Wang Longxiang Su Lu Wang Wei Du Huaiwu He Yujie Chen Zunzhu Li Qi Li Jianhua Sun Hongbo Luo Jinbang Liu Guangliang Shan Bing Du Yanhong Guo Dawei Liu Chang Yin Xiang Zhou on behalf of the china national Critical Care Quality Control {2.-the ECMO quality improvement action(EQIA)study Department of Critical Care Medicine State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing100730China information center Department/Department of information Management State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalPeking Union Medical College&Chinese Academy of Medical SciencesBeijing100730China Department of Medical Administration National Health Commission of the People’s Republic of ChinaBeijing100044China School of Population Medicine and Public Health Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100730China Department of Epidemiology and Biostatistics Institute of Basic Medicine SciencesChinese Academy of Medical Sciences(CAMS)&School of Basic MedicinePeking Union Medical CollegeBeijing100730China national Institute of Hospital Administration National Health Commission of the People’s Republic of ChinaBeijing100044China 不详

This cohort study was performed to explore the influence of intensive care unit(ICU)quality on in-hospital mortality of veno-venous(V-V)extracorporeal membrane oxygenation(ECMO)-supported patients in *** study involved all V-V ECMO-supported patients in 318 of 1700 tertiary hospitals from 2.17 to 2.19,using data from the national Clinical Improvement System and china national Critical Care Quality Control *** quality was assessed by quality control indicators and capacity *** the 2.63 V-V ECMO-supported patients in 318 hospitals,a significant correlation was found between ECMO-related complications and *** reintubation rate within 48 hours after extubation and the total ICU mortality rate were independent risk factors for higher in-hospital mortality of V-V ECMO-supported patients(cutoff:1.5%and 7.0%;95%confidence interval:1.05–1.48 and 1.04–1.45;odds ratios:1.2. and 1.2.;P=0.012.and P=0.015,respectively).Meanwhile,the V-V ECMO center volume was a protective factor(cutoff of≥50 cases within the 3-year study period;95%confidence interval:0.57–0.83,odds ratio:0.69,P=0.0001).The subgroup analysis of 864 patients in 11 high-volume centers further strengthened these ***,ICU quality may play an important role in improving the prognosis of V-V ECMO-supported patients.

关键词： veno-venous extracorporeal membrane oxygenation in-hospital mortality high-volume centers quality control intensive care unit capacity parameters

Influence of the cobalt concentration on optical and magnetic properties of zinc oxide

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Chinese science Bulletin 2010年第10期55卷 897-901页

作者： WANG LiWei,ZHANG FuJun,XU Zheng,ZHAO SuLing & LU LiFang Institute of Optoelectronics technology,beijing Jiaotong University Key {2. of Luminescence and Optical information (beijing Jiaotong University),Ministry of Education,beijing 100044,china Institute of Optoelectronics technology Beijing Jiaotong University Beijing China Ministry of Education Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Beijing China

A series of Co-doped ZnO thin films have been prepared by direct current reactive magnetron sputtering on glass *** structural characterization by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM) gave no evidence of second phase *** qualitative composition and chemical state were characterized by energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectronic spectrometry (XPS),*** results confirmed that Co was incorporated as Co3+,occupying the Zn2. sites in ZnO's wurtzite *** luminescence properties of the films were investigated by room temperature photoluminescence,and the optical properties were studied by optical *** magnetic analysis was carried out at room temperature and at 50 K by quantum Design MPMS (SQUID) *** results showed that all the Co-doped ZnO thin films prepared by direct current magnetron sputtering were not ferromagnetic above 50 K.

关键词：氧化锌钴氧化物磁性直流反应磁控溅射 X射线光电子能谱室温光致发光扫描电子显微镜纤锌矿结构

Further results on the margin explanation of boosting:new algorithm and experiments

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science china({2. sciences) 2012年第7期55卷 1551-1562页

作者： WANG LiWei 1,DENG XiaoCheng 2.,JING ZhaoXiang 1 & FENG JuFu 1 1 Key laboratory of Machine Perception,MOE,Peking University,beijing 100871,{2. 2.Microsoft Search technology center Asia,beijing 100080,{2. 1. Key laboratory of Machine Perception MOE Peking University Beijing 100871 China2. Microsoft Search Technology Center Asia Beijing 100080 China

Understanding the empirical success of boosting algorithms is an important theoretical problem in machine *** of the most influential works is the margin theory,which provides a series of upper bounds for the generalization error of any voting classifier in terms of the margins of the training *** an equilibrium margin (Emargin) bound which is sharper than previously well-known margin bounds is *** this paper,we conduct extensive experiments to test the Emargin ***,we develop an efficient algorithm that,given a boosting classifier (or a voting classifier in general),learns a new voting classifier which usually has a smaller Emargin *** then compare the performances of the two classifiers and find that the new classifier often has smaller test errors,which agrees with what the Emargin theory predicts.

关键词： boosting margin Emargin theory