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Research on the Long Time Swelling Properties of Poly (vinyl alcohol)/Hydroxylapatite Composite Hydrogel

Journal of Bionic Engineering 2009年第1期6卷 22-28页

作者： De-kun Zhang~(1.3), Da-gang Wang~2, Jun-jie Duan~(1.3), Shi-rong Ge~(2,3)1. School of Materials Science and Engineering, china University of Mining and Technology, Xuzhou 221.1., P. R. china2. School of Mechanical and Electrical Engineering, china University of Mining and Technology, Xuzhou 221.1., P. R. china3. Biotribology center, national Key Laboratory of Tribology, Tsinghua University, beijing 1.0083, P. R. china [a]School of Materials Science and Engineering China University of Mining and Technology Xuzhou 221116 P. R. China [b]School of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou 221116 P. R. China [c]Biotribology Center National Key Laboratory of Tribology Tsinghua University Beijing 100083 P. R. China

Poly(vinyl alcohol)/hydroxylapatite(PVA/HA)composite hydrogel was prepared by repeated freezing and *** water loss properties of the resultant hydrogel were investigated by using optical *** time immersion tests of PVA/HA composite hydrogel were carried out in the diluted calf serum solution to study the change laws of swelling properties with the freezing-thawing cycles and HA *** micro-morphologies of PVA/HA composite hydrogel after long time immersion were observed by means of the high-accuracy 3D *** results show that the swelling process of PVA/HA composite hydrogel is the converse process of its water *** time swelling ratio curves of PVA/HA composite hydrogel in the calf serum solution are manifested as four stages of quick increase,decrease,slow decrease and stable balance,and its equilibrium swelling ratio decreases with the increase of freezing-thawing cycles and HA *** is revealed that the network structure of the composite hydrogel immersed for a long period is significantly improved with the increase of HA content. Perfect network structures of PVA/HA composite hydrogel as well as full and equilibrium tissues after swelling equilibrium are obtained when the HA content is 3% and the number of freezing-thawing cycles is 7.

关键词： poly (vinyl alcohol) hydroxyapatite composite hydrogel swelling property morphology

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Mass Spectrometric Evidence of Heparin Disaccharides for the Catalytic Characterization of A Novel Endolytic Heparinase

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 840-844页

作者： Yapeng CHAO1.3, Shaoxiang XIONG2, Xiulan CHENG1. and Shijun QIAN1. 1.nstitute of Microbiology, Chinese Academy of Sciences, beijing 1.0080, {1. 2center of Mass Spectrometry, Institute of Chemistry, Chinese Academy of Sciences, beijing 1.0080, {1. 3Graduate School of the Chinese Academy of Sciences, beijing 1.0039, {1. Institute of Microbiology Chinese Academy of SciencesBeijing 100080 China Graduate School of the Chinese Academy of Sciencesbeijing 1.0039 China center of Mass Spectrometry Institute of Chemistry Chinese Academy of SciencesBeijing 100080 China

Heparinase from different sources can eliminate heparin or/and heparan sulfate into various low-molecular weight heparins with different characteristics. Porcine intestinal mucosa heparin was de- graded into a series of oligosaccharides by a novel heparinase from the species Sphingobacterium. Disaccha- ride components from the digests were separated and purified by ultrafiltration and HPLC. Five major peaks appeared as three types according to their retention time. The mass spectrometry of peak I mainly gave the non-sulfated disaccharide with the mass of 379 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 41. and 459 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 496 Da, hinting that they were disulfate- substituted disaccharides. No trisulfate-substituted disaccharides were detected in the mixture of the heparin digest though they were abundant in the heparin structure. The results revealed that the heparinase might specifically cut the sites with low sulfated domain in heparin.

关键词： electrospray ionization-mass spectrometry heparin disaccharides heparinase high perfor- mance liquid chromatography Sphingobacterium sp.

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A virtual reference satellite differential method for relative correction of satellite ephemeris errors

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Science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2300-2306页

作者： CAI ChengLin 1.3 , LI XiaoHui 2,3 & WU HaiTao 2,3 1.Gulin University of Electronic Technology, 541.04, china 2 {1. Time Service center, Chinese Academy of Sciences, Lintong 71.600, china 3 Key Laboratory of Precision Navigation and Timing Technology, {1. Time Service center, Chinese Academy of Sciences, Lintong 71.600, china 1. Gulin University of Electronic Technology Gulin 541004 China3. Key Laboratory of Precision Navigation and Timing Technology National Time Service Center Chinese Academy of Sciences Lintong 710600 China2. National Time Service Center Chinese Academy of Sciences Lintong 710600 China

In order to solve the problems that the novel wide area differential method on the satellite clock and ephemeris relative correction (CERC) in the non-geostationary orbit satellite constellation, a virtual reference satellite (VRS) differential principle using relative correction of satellite ephemeris errors is proposed. It is referred to be as the VRS differential principle, and the elaboration is focused on the construction of pseudo-range errors of VRS. Through qualitative analysis, it can be found that the impact of the satellite’s clock and ephemeris errors on positioning can basically be removed and the users’ positioning errors are near zero. Through simulation analysis of the differential performance, it is verified that the differential method is universal in all kinds of satellite navigation systems with geostationary orbit (GEO) constellation, Medium orbit (MEO) constellation or hybrid orbit constellation, and it has insensitivity to abnormal aspects of a satellite ephemeris and clock. Moreover, the real time positioning accuracy of differential users can be maintained within several decimeters after the pseudo-range measurement noise is effectively weakened or eliminated.

关键词： wide area differential method virtual reference satellite (VRS) satellite ephemeris errors satellite clock errors constellation

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An analysis of the wide area differential method of geostationary orbit satellites

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Science china(Physics,Mechanics & Astronomy) 2009年第2期52卷 310-314页

作者： CAI ChengLin1.2,3?, LI XiaoHui1.& WU HaiTao1.1.national Time Service {1., Chinese Academy of Sciences, Lintong 71.600, china 2 Hunan Institute of Humanities, Science and Technology, Loudi 41.000, china 3 Graduate University of Chinese Academy of Sciences, beijing 1.0049, china 1. national Time Service {1. Chinese Academy of Sciences Lintong 710600 China 2. Hunan Institute of Humanities Science and Technology Loudi 417000 China 3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

This work aims to obtain a wide area differential method for geostationary orbit (GEO) constellation. A comparison between the dilution of precision (DOP) of four-dimensional (4D) calculation including sa- tellite clock errors and ephemeris errors and that of three-dimensional (3D) calculation only including ephemeris errors with the inverse positioning theory of GPS shows the conclusion that all the 3D PDOPs are greatly reduced. Based on this, a basic idea of correcting satellite clock errors and ephem- eris errors apart is put forward, and moreover, a specific method of separation is proposed. Satellite clock errors are separated in a master station with time synchronization, and all the remaining pseu- do-range errors after the satellite clock errors have been deducted are used to work out ephemeris corrections of all GEO satellites. By a comparative analysis of user positioning accuracy before and after differential, the wide area differential method is verified to be quite valid for GEO constellation.

关键词： geostationary orbitsatellite dilution of precision satellite ephemeris errors satellite clock errors wide area differential method

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Polynomial analysis of canopy spectra and biochemical component content inversion

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Science china Earth Sciences 2005年第10期48卷 1780-1791页

作者： YAN Chunyan1. LIU Qiang1. NIU Zheng1. WANG Jihua2, HUANG Wenjiang2 & LIU Liangyun 2 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 1.01.1. china 2. national Engineering Research center for Information Technology in Agriculture, beijing 1.0089, china State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University beijing china national Engineering Research {1. for Information Technology in Agriculture beijing china

A polynomial expression model was developed in this paper to describe directional canopy spectra, and the decomposition of the polynomial expression was used as a tool for re-trieving biochemical component content from canopy multi-angle spectra. First, the basic formula of the polynomial expression was introduced and the physical meaning of its terms and coeffi-cients was discussed. Based on this analysis, a complete polynomial expression model and its decomposition method were given. By decomposing the canopy spectra simulated with SAILH model, it shows that the polynomial expression can not only fit well the canopy spectra, but also show the contribution of every order scattering to the whole reflectance. Taking the first scattering coefficients a1. and a01.for example, the test results show that the polynomial coefficients reflect very well the hot spot phenomenon and the effects of viewing angles, LAI and leaf inclination angle on canopy spectra. By coupling the polynomial expression with leaf model PROSPECT, a canopy biochemical component content inversion model was given. In the simulated test, the canopy multi-angle spectra were simulated by two different models, SAILH and 4-SCALE re-spectively, then the biochemical component content was retrieved by inverting the coupled polynomial expression + PROSPECT model. Results of the simulated test are promising, and when applying the algorithm to measured corn canopy multi-angle spectra, we also get relatively accurate chlorophyll content. It shows that the polynomial analysis provides a new method to get biochemical component content independent of any specific canopy model.

关键词： polynomial expression, canopy spectra, decomposition, biochemical component content, inversion.

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Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu mineralization

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Science china Earth Sciences 2004年第3期47卷 221-231页

作者： HOU Zengqian1. QU Xiaoming1. WANG Shuxian2, DU Andao2, GAO Yongfeng3 & HUANG Wei4 1. Institute of Mineral Resources, Chinese Academy of Geological Sciences, beijing 1.0037, {1. 2. national center of Geoanalysis, Chinese Academy of Geological Sciences, beijing 1.0037, {1. 3. Shijiazhuang College of Economy, Shijiazhuang 056000, {1. 4. Xizang Bureau of Geology and Mineral Resources, Lhasa 850000, {1. Chinese Acad Geol Sci Inst Mineral Resources Beijing 100037 Peoples R China Chinese Acad Geol Sci Natl Ctr Geoanal Beijing 100037 Peoples R China Shijiazhuang Coll Econ Shijiazhuang 056000 Peoples R China Xizang Bur Geol & Mineral Resources Lhasa 850000 Peoples R China

The Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. The belt trends 350 km long along the EW-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the SN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 1. Ma to 1. Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (1.—1. Ma) and mafic dykes (1.—1. Ma). The timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 1.7Re-1.7Os isochron with a highly pre-cise age of (1..76?.22) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (1..04?.1.) Ma. Re-Os model ages for two molybdenite samples from Lakang抏 deposit vary from 1..5 Ma to 1..6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.9971. and an isochron age of (1..39?.22) Ma (1. error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. The emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 21.23 Ma, and formed in a post-collision crustal ex-tension env

关键词： porphyry copper deposit, Re-Os age, Gangdese, Tibetan plateau.

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Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset

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Science china Earth Sciences 2006年第11期49卷 1223-1232页

作者： HE Jinhai1. WEN Min2, DING Yihui3 & ZHANG Renhe2 1. Jiangsu Key Laboratory of Meteorological Disaster (KLME), Nanjing Institute of Meteorology, Nanjing University of Informa- tion Science and Technology, Nanjing 21.044, china 2. State Key Laboratory of Severe Weather (LaSW), Chinese Academy of Meteorological Sciences, {1. 1.0081. china 3. national Climate center, Chinese Meteorological Administration, {1. 1.0081. china 1. Jiangsu Key Laboratory of Meteorological Disaster (KLME) Nanjing Institute of Meteorology Nanjing University of Information Science and Technology Nanjing 210044 China 2. State Key Laboratory of Severe Weather (LaSW) Chinese Academy of Meteorological Sciences Beijing 100081 China 3. national Climate {1. Chinese Meteorological Administration Beijing 100081 China

The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-china Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-china Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-china Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-china Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical high belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-china Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-china Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical high and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-china Peninsula to South china Sea.

关键词： Asian-Australian 'land bridge', tropical convection, Indo-china Peninsula, the splitting of boreal subtropical high belt, East Asian summer monsoon onset.

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Factors governing formation of todorokite at atmospheric pressure

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Science china Earth Sciences 2005年第10期48卷 1678-1689页

作者： CUI Haojie1. FENG Xionghan1. LIU Fan1. TAN Wenfeng1.& HE Jizheng2 1. College of Resources and Environment, Huazhong agricultural University, Wuhan 430070, {1. 2. Research center for Eco-environmental Sciences, Chinese Academy of Sciences, beijing 1.0085, {1. College of Resources and Environment Huazhong agricultural University Wuhan {1. Research center for Eco-environmental Sciences Chinese Academy of Sciences {1. china

Todorokite commonly occurs in Earth surface environments. The factors governing formation of todorokite, such as reaction temperature, metal ions, dissolved O2 and pH, were investigated in this paper. Results showed that the forming rate of todorokite and its crystallinity decreased with falling reaction temperature, and the effect of temperature was more significant than that of other parameters. Nature of metal ions in the interlayer of buserite precursor and the structure of the buserite precursor obviously affected buserite transformation into todorokite. Weak bonding between the metal ions and MnO6 layer of buserite was favorable to todorokite formation. The rate of todorokite formation was promoted at a lower temperature with appropriate bubbling of O2. The pH in the system slightly influenced the todorokite formation, and todorokite could also be formed in a weak alkali medium or in a slightly acidic medium. Aged buserite pre-cursor more easily form todorokite than the unaged one.

关键词： todorokite, buserite, manganese oxide mineral, atmospheric pressure, transformation.

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A comparative analysis on two solar proton events

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Chinese Science Bulletin 2007年第1期52卷 47-51页

作者： LE GuiMing1,2,3,4, HAN YanBen2 & ZHANG YiJun3 1 Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites, china Meteorological Administration, beijing 100081, china 2 national Astronomical Observatories, Chinese Academy of Sciences, beijing 100012, china 3 Chinese Academy of Meteorological Sciences, china Meteorological Administration, beijing 100081, china 4 national center for Space Weather, china Meteorological Administration, beijing 100081, china Key Laboratory of Radiometric Calibration and Validation for EnvironmentalSatellites China Meteorological Administration Beijing 100081 China

This paper presents a comparative analysis on the two Solar Proton Events (SPE), which occurred on 1. July 2000 (Bastille Day) and 28 October 2003 (28OCT03) respectively. It is found that although the peak flux of the latter seemed to be greater than that of the former based on geostationary observations, the maximum intensities of the energetic protons (>1. MeV and 30 MeV) during the Bastille Day event were all higher than those of the 28OCT03 event according to the interplanetary observations. Further analysis indicated that the quantity of the seed particles, which could be accelerated to the energies exceeding 1. and 30 MeV by the Coronal Mass Ejection (CME)-driven shock on 1. July 2000, was far larger than that of the 28OCT03 event. In the Bastille Day case, when the CME approached to the height around 1. R⊙, the CME-driven shock would reach its maximum capacity in accelerating the solar en- ergetic protons (>1.0 MeV). In contrast, on 28 October 2003, when CME approached to the height about 58R⊙, the CME-driven shock reached its highest potential in accelerating the solar energetic protons of the same category. At this moment, the peak flux (>1.0 MeV) was about 1.5 pfu, which was much lower than 355 pfu measured on 1. July 2000. This demonstrated that in the Bastille Day event, the quantity of the seed particles, which could be accelerated to the energy beyond 1.0 MeV, was significantly larger than its counterpart in the 28OCT03 case. Therefore, the peak flux of an SPE event depends not only on the interplanetary intensity of the solar energetic particles, but also on the velocity of the associated CME-driven shock, and the quantity of the seed particles as well as on the interplanetary magnetic en- vironment. This paper also reveals that the magnetic sheath associated with ICME on 28 October 2003 captured a large number of solar energetic protons, including those having energy greater than 1.0 MeV.

关键词：太阳质子 CME 太阳耀斑太阳系

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A new type of Shipboard Meteorological Satellite Receiving-processing System

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Acta Oceanologica Sinica 2000年第1期19卷 35-46页

作者： Xie Simei Hao Chunjiang Zou Bin Jing Qiyi Liao Xiaohong Sheng Xiaowen Zhang Canrong (1. national Research {1. for Marine Environment Forecasts, beijing 1.0081. china 2, Second Institute of china Aerospace Corporation 3. beijing Chuanyi Electric Compan Natl. Res. Ctr. Mar. Environ. F. Beijing 100081 China Second Inst. of china Aerosp. Corp. China beijing Chuanyi Electric Company Chinese Academy of Sciences Beijing China

The Shipboard Meteorological Satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean. This system can suit to the climate environment of very high temperature high moisture and very low temperature - supersaturation; it has a self-protection ability to against the hurricane - force wind over force 1. and the strong vibration during icebreaking, as well as strong magnetic disturbance. It has two sets of receiving-imagery processing systems for polar orbit low-resolution and quasi-stationary high-solution satellites. The key creation Points of this system are as follows: 1. the active gyro-control stabilization platform and a mixed mounting system of three rotating a - B and x -- y axes are used. It solved the tracing difficulties both in the low elevation angle and very high elevation angle of polar-orbit satellite, even in the status of ship moving with continuously changing its poition, direction and ship roll and pitch. 2. Imagery processing subsystem. The newest BORLAND-- DELPHI language and PASCAL language pro gramming software are used under WINDOWS 95 environment. It has a dynamic positioning nested-grid system and electric mapping grid data system. It can show the latitude-longitude of any point on the map, and marks any object such as ship, station or island, and draws the route. It can monitor cloud and temperature, forest fire, anomalous change of ocean and land. It can output satellite cloud maps of 24 bit with very high clarity. This system is very advanced in technique for the whole structure with the features of small volume, light weight and very low cost. It suits to very bad climate and ocean environment. Its imagery process ing system has complete functions with high resolution and being very easy to operate. It is not only suit to land use, but also and specially to all kinds of ship over the sea. It can be exte

关键词： Shipboard Meteorological Satellite Receiving-processing System imagery processing system active gyro-control platform

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