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Direct CP violation in hadronic B decays

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Science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2 & Lü Caidian3.1. Department of Physics, Lishui university, Lishui 3.3.00,china 2. Department of Physics, Shanghai Jiaotong university, Shanghai 20003., china 3. Institute of High Energy Physics, Beijing 100049,china Department of Physics Lishui University Lishui 323000 China Department of Physics Shanghai Jiaotong University Shanghai 200030 China Institute of High Energy Physics Beijing 100049 China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

Arnold's theorem on properly degenerate systems with the Russmann nondegeneracy

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Science china Mathematics 2005年第12期48卷 1656-1669页

作者： HAN Yuecai & LI Yong college of Mathematics, jilin university, Changchun 13.012, china 1. college of Mathematics Jilin University 130012 Changchun China

In this paper, we investigate the persistence of invariant tori for the nearly in-tegrable Hamiltonian system H(x,y) = h(y) + εp(x,y) + ε2Q(x,y), where h(y) and εp(x,y) satisfy the Russmann non-degenerate condition. Mainly we overcome the difficulties that the order of the parameter E in the perturbation ε2Q(x,y) is not enough and that the measure estimate involves in parts of frequencies with small parameter.

关键词： Arnold’s theorem the Russmann non-degenerate condition.

Changes of decay rates of radioactive ^(111)In and ^(3.)P induced by mechanic motion

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Science china chemistry 2007年第2期50卷 170-174页

作者： HE YuJian1,QI Fei2 & QI ShengChu3.1 college of chemistry and Chemical Engineering,Graduate university of Chinese Academy of Sciences,Beijing 100049,{3. 2 No. 1,Gravenhurst Court,Gaithersburg,Md 20878,USA 3.Department of Applied chemistry,Peking university,Beijing 100871,{3. 1. college of chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 2. No. 1 Gravenhurst Court Gaithersburg Md 20878 USA 3. Department of Applied chemistry Peking University Beijing 100871 China

The changes of decay rates of radionuclide 111In(electron capture) and 3.P(β decay) induced by exter-nal mechanic motion are studied. The results indicate that,in the external circular rotation in clockwise and anticlockwise centrifuge on Northern Hemisphere(radius 8 cm,2000 r/min) ,the half life of 111In compared with the referred(2.83.d) is decreased at 2.83. and increased at 1.77%,respectively;the half life of 3.P compared with the referred(14.29 d) is decreased at 3.78% and increased at 1.75%,respec-tively. When the clockwise and anticlockwise rotations increase to 4000 r/min,the half life of 111In is decreased at 11.3.% and increased at 6.3.%,respectively;the half life of 3.P is decreased at 10.08% and increased at 4.3.%,respectively. When the circular rotation is removed,the decay rates of 111In and 3.P return back to the referred,respectively. It is found that the external circular rotations in clockwise and anticlockwise centrifuge selectively increased and decreased the decay rates of 111In and 3.P,respec-tively,and the effects are strongly dependent on the strength of circular rotation. It is suggested that these effects may be caused by the chiral interaction.

关键词： circular rotation helical motion 111In 3.P decay rate chirality

Regulation of eight avr genes by hrpG and hrpX in Xanthomonas campestris pv. campestris and their role in pathogenicity

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Progress in Natural Science:Materials International 2006年第12期16卷 1288-1294页

作者： XU Rongqi~ 1,3., LI Xianzhen~3. WEI Hongyu~3. JIANG Bole~2, LI Kai~3. HE Yongqiang~ 2,3., FENG Jiaxun~ 1,3.and TANG Jiliang~ 1,2 **(1. Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization 2. The Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering 3. college of Life Science and Technology, Guangxi university, Nanning 53.004, china) Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization Guangxi University Nanning 530004 China college of Life Science and Technology Guangxi University Nanning 530004 China The Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering Guangxi University Nanning 530004 China

Eight putative avirulence genes in Xanthomonas campestris pv. campestris (Xcc) strain 8004 were characterized by Tn5gusA5 mutagenesis and gene expression analysis. The virulence test of mutants on Chinese radish showed that all mutants in individual avr genes except avrBs2 mutant were not significantly different from the wild type in virulence. The avrBs2 mutant showed reduced virulence and bacterial growth in planta. Gene expression analysis using β-glucuronidase as reporter indicated that avrBs1.1,avrBs1,avrXccB,avrXccC,avrXccE1 were regulated by hrpG, whereas avrXccA1, avrXccA2 and avrBs2 were not. RT-PCR analysis showed that all hrpG-regulated genes except avrBs1 were also regulated by hrpX. In addition, it was demonstrated that avrBs1 was responsible for elicitation of a type III dependent hypersensitive reaction (HR) on nonhost plant pepper ECW-10R, and wild type Xcc 8004 was unable to cause HR on pepper ECW-20R.

关键词： Xanthomonas campestris pv. campestris avirulence gene virulence expression analysis.

Applications of functionalized ionic liquids

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Science china chemistry 2006年第5期49卷 385-401页

作者： LI Xuehui1, ZHAO Dongbin2,3. FEI Zhaofu2 & WANG Lefu1 1. Department of Chemical Engineering, Guangdong Provincial Laboratory of Green Chemical Technology, South china Uni-versity of Technology, Guangzhou 510641, china 2. Swiss Federal Institute of Technology, Lausanne, EPFL, CH-1015 Lausanne, Switzerland 3. PKU Green chemistry Center, Beijing National Laboratory for Molecular Sciences, {3. of chemistry and Molecular Engineering, Peking university, Beijing 100871, china 1. Department of Chemical Engineering Guangdong Provincial Laboratory of Green Chemical Technology South China University of Technology Guangzhou 510641 China 2. Lausanne EPFL Swiss Federal Institute of Technology CH-1015 Lausanne Switzerland 3. PKU Green chemistry Center Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Recent developments of the synthesis and applications of functionalized ionic liquids (including dual-functionalized ionic liquids) have been highlighted in this review. Ionic liquids are at-tracting attention as alternative solvents in green chemistry, but as more functionalized ILs are pre-pared, a greater number of applications in increasingly diverse fields are found.

关键词： ionic liquids functionalized ionic liquids dual-functionallzed ionicliquids reaction media asymmetric synthesis nano-materials porous materials lubricants flue-gas desulfurization oil desul-furization

High-efficiency and flexible photonic microwave harmonic down-converter based on self-oscillation optical frequency combs

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Chinese Optics Letters 2024年第6期22卷 196-204页

作者： Xin Zhang Tao Pu Huatao Zhu Yunshan Zhang Gengze Wu Jin Li jilin Zheng college of Information and Communications National University of Defense TechnologyWuhan 430010China college of Communications Engineering Army Engineering University of PLANanjing 210007China college of Electronic and Optical Engineering&college of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China

Photonic microwave harmonic down-converters (PMHDCs) based on self-oscillation optical frequency combs (OFCs) are interesting because of their broad bandwidth compared with plain optoelectronic oscillators. In this paper, a high-efficiency and flexible PMHDC is proposed and demonstrated. The properties of the OFC, such as the carrier-to-noise ratio (CNR),bandwidth and free spectral range (FSR), and the influence of optical injection, are investigated. The broadband OFC provides a frequency tunable and high-quality local oscillation (LO), which guarantees flexible down-conversion for the radio frequency (RF) signal. The sideband selective amplification (SSA) effect not only improves the conversion efficiency but also promotes single-sideband modulation. The conversion range can reach 100 GHz. The 12–40 GHz RF signal can be downconverted to intermediate frequency (IF) signals with a high conversion efficiency of 14.9 dB. The fixed 40-GHz RF signal is flexibly down-converted to an IF signal with the frequency from 55.4 to 2129.4 MHz. The phase noise of an IF signal at a frequency offset of 10 kHz is the same as that of the input RF signal. The PMHDC shows great performance and will find applications in radio-over-fiber (RoF) networks, electronic warfare receivers, avionics, and wireless communication systems.

关键词： frequency down-conversion optical frequency comb optical injection optoelectronic oscillation

Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

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Science china chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2,3. SUN Yele1 & WANG Zifa3.1. The Center for Atmospheric Environmental Study, Department of chemistry, Beijing Normal university, Beijing 100875, china 2. Center for Atmospheric chemistry Study, Department of Environmental Science & Engineering, Fudan university, Shanghai 20043., china 3. LAPC/NZC, Institute of Atmospheric Physics, CAS, Beijing 100029, china 1. The Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University 100875 Beijing China 2. Center for Atmospheric chemistry Study Department of Environmental Science & Engineering Fudan University 200433 Shanghai China 3. Institute of Atmospheric Physics CAS LAPC/NZC 100029 Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 3.%―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62% （3.%―86%） of the total mineral aerosols in TSP, 69% （52%―90%） in PM10, and 76% （59%―93.） in PM2.5 in spring, and 69% （52%―83.）, 79% （52%―93.）, and 45% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only20% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

Status of study on biological and toxicological effects of nanoscale materials

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Science china chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3.1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of Sciences, Beijing 100049, china 2. college of chemistry and Molecular Engineering, Peking {3., Beijing 100871, china 3. Department of Occupational and Environmental Health Sciences, School of Public Health, Peking {3., Beijing 100083. china 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. college of chemistry and Molecular Engineering Peking University 100871 Beijing China 3. Department of Occupational and Environmental Health Sciences School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

Detection of Prorocentrum donghaiense using sandwich hybridization integrated with nuclease protection assay

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Acta Oceanologica Sinica 2009年第2期28卷 121-126页

作者： CHEN Jie ZHEN Yu MI Tiezhu YU Zhigang college of Marine Life Science Ocean University of China Qingdao 266003 China college of Environmental Science and Engineering Ocean University of China Qingdao 266100 China college of chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

Prorocentrum donghaiense is an important harmful algae bloom （HAB） causing creature in china＇s seas, and the conventional visual detection can not cope with long-term monitoring and highthroughput sampling projects. An assay for P. donghaiense with sandwich hybridization integrated with nuclease protection assay （NPA-SH） was established. Tests with mixed samples and spiked field ones confirmed its good specificity and sensitivity. The cell number of P. donghaiense correlated well with the optical density, and the regression equation is y=4× 10^- 6x＋ 0.694 9, in which x is the cell number, and y is the optical density, with r2=0.953.5. These results show that the NPA-SH method has good feasibility in the detection of P. donghaiense. Results of NPA-SH and microscopy are excellent for each sample. The NPA-SH method was a simple way in quantitative detection of P. donghaiense, and the whole process could be finished in about six hours, which provided a new approach in high-throughput sampling and long-term monitoring of P. donghaiense.

关键词： Prorocentrum donghaiense ribosomal RNA S1 enzyme sandwich hybridization integrated with nuclease protection assay (NPA-SH)