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Is the PhyloCode better than Linnaean system?—— New development and debate on biologi-cal nomenclatural issues

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Chinese Science Bulletin 2003年第3期48卷 308-312页

作者： GAO Keqin & SUN Yuanlin school of Earth and Space Sciences, peking university, beijing 100871, China school of Earth and Space Sciences Peking University Beijing 100871 China

The Linnaean system provides ultimate means governing biological nomenclature and classification. With series of modification, this system has admirably served bio-logical sciences for some 250 years. The new PhyloCode, however, advocates the phylogenetic nomenclature that radically alternates the current nomenclatural rules. The new proposals upset many systematic biologists and have provoked hot debate on nomenclatural issues. Binomial no-menclature and hierarchical classification are the key com-ponents of the Linnaean system. Proposed abandonment of these in the PhyloCode is widely criticized for it would not help to promote systematics but create chaos. It is not the Linnaean system but the phylogenetic nomenclature that should be abandoned.

关键词：生物分类生物命名法林奈系统系统代码法特点

A new simulated annealing method of designing NMR biplanar shim coils

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Progress in Natural Science:Materials International 2006年第7期16卷 747-752页

作者： QI Feng, TANG Xin, WANG Weimin, SHEN Yifei, LIU Shaopo and JIANG Zhongde ( Key Laboratory for Quantum Information and Measurements of Ministry of Education, school of Electronics Engineering & Computer Science, peking university, beijing 100871, China Institute of Heavy Ion {3., and beijing Key Laboratory of Medical {3. and Engineering, Physical school, peking university, beijing 100871, China) peking Univ Sch Elect Engn & Comp Sci Minist Educ Key Lab Quantum Informat & Measurements Beijing 100871 Peoples R China peking Univ Sch Phys Beijing Key Lab Med Phys & Engn Beijing 100871 Peoples R China peking Univ Inst Heavy Ion Phys Beijing 100871 Peoples R China

A new SA (simulated annealing) method is presented for the design of longitudinal shim coils for NMR (nuclear magnetic resonance) equipment. First, AGL (adaptive Gauss-Lobatto) quadrature used by the traditional SA method is analyzed. Two kinds of complete elliptic integrals are introduced to integrate the spatial magnetic field, which increases the computing speed by 13. 3.times. Then, the system energy calculation is extended to the field of the z-axis. The results illustrate that the coil-set efficiency designed by the new SA method is 15 % higher than that of the traditional one, and the field inhomogeneity is reduced from 1.20 % to 0.49 % . Finally, a prototype of coil assembly for NMR rock-core analyzer is built, and the experimental results are in good agreement with the theoretically calculated results.

关键词： NMR shim coil design simulated-annealing method complete elliptic integral.

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 university, {3., China 3. Department of Occupational and Environmental Health Sciences, school of Public Health, peking university, beijing 100083. China Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences Beijing China College of Chemistry and Molecular Engineering Peking University Beijing China Department of Occupational and Environmental Health Sciences School of Public Health Peking University 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.

Raman OH stretching vibration of ice Ih

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Progress in Natural Science:Materials International 2009年第11期19卷 1651-1654页

作者： Qiang Sun~*,Haifei Zheng The school of Earth and Space Sciences,peking university,beijing 100871,China The school of Earth and Space Sciences Peking University Beijing 100871 China

From our recent research on ice Ih(hexagonal ice),we deduce that free OH groups exist at the ice surface and that dangling OH influences the interior of the proton-disordered ***,exploiting recent research by others on water molecular clusters,we propose a new interpretation for the Raman OH stretching vibration of ice *** deconvolute the Raman OH stretching vibration of ice Ihinto four sub-bands,with each sub-band being ascribed to OH vibrations engaged in different types of hydrogen bonding.

关键词： Raman Hydrogen bonding Ice I_h

A novel endorectal RF coil for high resolution MRI and spectroscopy of the prostate

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Progress in Natural Science:Materials International 2005年第5期15卷 472-476页

作者： ZHANG Hongjie 1,2, SONG Xiaoyu1, WANG Xiaoying3. XU Pingfang1 and BAO Shanglian1*(1. beijing Key Laboratory of Medical physics & Engineering, peking university, {3., China 2. Navy General Hospital, beijing 10003., China 3. peking university First Hospital, beijing 10003., China) beijing Key Laboratory of Medical physics & Engineering Peking University Beijing 100871 China Navy General Hospital Beijing 100037 China peking university First Hospital Beijing 100034 China

The diagnosis of prostate diseases by magnetic resonance imaging (MRI) in vivo is sometimes difficult for the lower signal to noise ratio (SNR). To increase the SNR of the prostate image, we designed a RF coil that can be inserted into rectum and was named endorectal coil. The properties of RF coil were evaluated using a network analyzer. Moreover the images and spectroscopy of a special phantom were acquired and the results were compared to those of the commercial TORSO coil (G.E. Medical Systems, USA). Our coil gave a significantly higher SNR at the region of interest (ROI). The achieved high local SNR and resulting high spatial resolution would add more anatomic and biochemical information to the diagnosis of prostate diseases.

关键词： MRI RF coil endorectal coil.

Biodegradation of heavy oils by halophilic bacterium

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Progress in Natural Science:Materials International 2009年第8期19卷 997-1001页

作者： Ruixia Hao , Anhuai Lu school of Earth and Space Sciences, peking university, beijing 100871, China school of Earth and Space Sciences Peking University Beijing 100871 China

A halophilic bacterial strain TM-1 was isolated from the reservoir of the Shengli oil field in East China. Strain TM-1, which was found to be able to degrade crude oils, is a gram-positive non-motile bacterium with a coccus shape that can grow at temperatures of up to 58 °C and in 18% NaCl solution. Depending on the culture conditions, the organism may occur in tetrads. In addition, strain TM-1 produced acid from glucose without gas formation and was catalase-negative. Furthermore, strain TM-1 was found to be a facultative aerobe capable of growth under anaerobic conditions. Moreover, it produced butylated hydroxytoluene, 1,2-benzenedicarboxylic acid-bis ester and dibutyl phthalate and could use different organic substrates. Laboratory studies indicated that strain TM-1 affected different heavy oils by degrading various components and by changing the chemical properties of the oils. In addition, growth of the bacterium in heavy oils resulted in the loss of aromatic hydrocarbons, resins and asphaltenes, and enrichment with light hydrocarbons and an overall redistribution of these hydrocarbons.

关键词： Halophilic bacterium Metabolite Heavy oil Degradation

The study of two-color excitation upconversion of Pr(0.5)Yb(3.:ZBLAN

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Science China(physics,Mechanics & Astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1 & SONG Zengfu2 1. Applied Optics beijing Area Major Laboratory, Analysis and testing center, beijing Normal university, beijing 100875, China 2. peking university, physics school, beijing 100871, China Applied Optics beijing Area Major Laboratory Analysis and testing center Beijing Normal University Beijing China physics school Peking University Beijing China

The excited state absorption upconversion of Pr(0.5)Yb(3.:ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 63..8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3.)→1I6(Pr3.) and 1G4(Pr3.)→3.1(Pr3.)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3.)→3.2(Pr3.), and the 803.7 nm upconversion excitation transition 3.6(Pr3.)→1D2(Pr3.). The upconversion excitation transition 1G4(Pr3.)→1I6(Pr3.) is strong because its oscillator strength f = 23.040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3.:ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.

Cascade algorithm and multiresolution analysis on the Heisenberg group

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Progress in Natural Science:Materials International 2005年第7期15卷 602-608页

作者： LIU Heping, LIU Yu, PENG Lizhong and CHU Xiaoyong (LMAM, school of Mathematical Sciences, peking university, beijing 100871, China) LMAM School of Mathematical Sciences Peking University Beijing 100871 China

In this paper we investigate the relationship between the convergence of cascade algorithm and orthogonal (or biorthogo-nal) multiresolution analysis on the Heisenberg group. It is proved that the (strong) convergence of cascade algorithm together with the perfect reconstruction condition induces an orthogonal multiresolution analysis and vice versa . Similar results are also proved for biorthogo-nal multiresolution analysis.

关键词： Heisenberg group cascade algorithm multiresolution analysis refinable functions.

Fabrication of multi-sectional TiO_2 nanotube arrays by anodization

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Science China Chemistry 2010年第5期53卷 1067-1072页

作者： LI ShiQi,YIN JianBo & ZHANG GengMin Key Laboratory for the physics and Chemistry of Nanodevices and Department of Electronics,peking university,beijing 100871,China Key Laboratory for the physics and Chemistry of Nanodevices and Department of Electronics Peking University Beijing China

We report a facile method to grow multi-sectional TiO2 nanotube arrays consisting of alternating bamboo-shaped and smooth-walled nanotube sections by *** key factors are necessary for obtaining these ***,in order to avoid possible disruptions between the conjoint sections of the nanotube,the distribution of hydrogen ions is suggested not to be fiercely disturbed when switching from the first to the second ***,to avoid the disruption of the nanotube at the joint which results from the disparity in diameters between sections,the direct current voltage is set to be the maximum of the square wave *** newly developed TiO2 nanotube arrays are expected to have potential applications in solar cells,drug release and delivery systems.

关键词： titanium dioxide titania nanotube anodic oxidation