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Physiological and ultralstructural changes of Chlorella sp. induced by UV-B radiation

Progress in Natural Science:Materials International 2005年第8期15卷 678-683页

作者： YU Juan1. TANG Xuexi1., ZHANG Peiyu 1.2. TIAN Jiyuan1.and DONG Shuanglin1.1. Division of Life Science and {1., Ocean University of china, Qingdao 2.6003, china 2. college of Life Sciences, Qufu Normal University, Qufu 2.31.53, china) Division of Life Science and technology Ocean University of China Qingdao 266003 China. college of Life Sciences Qufu Normal University Qufu 2731653 China

In order to investigate the mechanisms of enhanced UV-B radiation on algae, the effects of UV-B radiation on the physiological and ultrastructural changes of Chlorella sp. were examined. The results showed that UV-B radiation could inhibit the growth and photosynthesis of microalgae. UV-B radiation at lower doses increased the photosynthetic pigment (chlorophyll a (Chla) and carotenoid (Car)) contents, while at higher doses of UV-B radiation Chla and Car contents were decreased. The ultrastructure of Chlorella sp. without exposure to UV-B showed that the thylakoid lamellae were clear and regular, the stroma of its chloroplast was apparent and clear. The globules with photosynthetic pigments and the cristae of mitochondria were clearly seen. After exposure to UV-B radiation at dose of 2.88 kJ/m2. the thylakoid lamellae of Chlorella sp. were lost and dissolved, the globules which contained photosynthetic pigments in chloroplast were bleached; some mitochondria cristae were dissolved; slight plasmolysis was found in some Chlorella sp. cells. After exposure to 5.76 kJ/m2.UV-B radiation, the thylakoid was in disarray and disintegration, plasmolysis was found in most cells, and the cell wall was broken and began to fall out. Many blank areas were observed in cells, mitochondria were seriously deformed and most of the mitochondria cristae were dissolved. Also, globules containing photosynthetic pigments in chloroplast were bleached and some empty globules were found in chloroplast. Therefore, UV-B radiation could damage cell structure of Chlorella sp., and this damage increased with the dose of UV-B radiation they exposed to.

关键词： UV-B radiation physiological changes ultrastructure Chlorella sp.

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The equilibrium between diagenetic calcites and dolomites and its impact on reservoir quality in the sandstone reservoir of Kela 2.gas field

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Progress in Natural Science:Materials International 2007年第9期17卷 1051-1058页

作者： Gao Zhiqian1.Yu Bingsong2.3 and Lai Xingyun2.3(1.School of Energy resources,china University of {2.,Beijing 1.0083,china 2.State Key Laboratory of Geological Processes and mineral resources,china University of {2.,Beijing 1.0083,china 3.Ministry of Education Key Laboratory of Lithosphere Structure,Deep Processes and Exploration Technique,china University of {2.,Beijing 1.0083,china) School of Energy resources China University of Geosciences Beijing 100083 China State Key Laboratory of Geological Processes and mineral {1. China University of Geosciences Beijing 100083 China Ministry of Education Key Laboratory of Lithosphere Structure Deep Processes and Exploration Technique China University of Geosciences Beijing 100083 China

Based on the equilibrium theory of chemical reactions between water and rocks,this paper establishes a thermodynamic phase relationship diagram among calcites,dolomites and water solution under the condition of diagenesis based on the thermodynamic database of related minerals and fluids and dolomite's degree of order *** has been discovered that the equilibrium between calcites and dolomites in the diagenetic environment is strongly impacted by temperature and the Ca/Mg ratios in groundwater,and that the dolomite's degree of order in the diagenetic environment is a function of crystallization temperature and time,not controlled by water ***,the authors make a further analysis of the close relationship of chemical reaction between carbonate cements and pore water in the sandstone reservoirs of Kala {1.gas field in Kuche *** can be seen that there are different impacts on sandstone reservoir quality among the equilibrium system of calcites,dolomites and pore water at different depths of reservoirs.

关键词： diagenesis equilibrium between calcites and dolomites secondary pores Kela 2.gas field

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The kink-soliton and antikink-soliton in quasi-one-dimensional nonlinear monoatomic lattice

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Science china(Physics,Mechanics & Astronomy) 2005年第2期48卷 150-157页

作者： XU Quan1.& TIAN Qiang2.1. Scientific and Technological Office, Daqing Teacher {1., Daqing 1.371.0} china 2. Department of Physics , Beijing Normal University, Beijing 1.0875, china Scientific and Technological Office Daqing Teacher College Daqing 163712 China Department of Physics Beijing Normal University Beijing 100875 China

The quasi-one-dimensional nonlinear monoatomic lattice is analyzed. The kink-soliton and antikink-soliton are presented. When the interaction of the lattice is strong in the x-direction and weak in the y-direction, the two-dimensional (2.) lattice changes to a quasi-one-dimensional lattice. Taking nearest-neighbor interaction into account, the vibration equation can be transformed into the KPI, KPII and MKP equation. Considering the cubic nonlinear potential of the vibration in the lattice, the kink-soliton solution is presented. Considering the quartic nonlinear potential and the cubic interaction potential, the kink-soliton and antikink-soliton solutions are presented.

关键词： two-dimensional nonlinear lattice, quasi-one-dimensional nonlinear lattice, kink-soliton, antikink-soliton.

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Energy analysis for damage and catastrophic failure of rocks

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Science china(Technological Sciences) 2011年第S1期54卷 199-209页

作者： XIE HePing 1,2.LI LiYun 2.1,JU Yang 2.PENG RuiDong 2.& YANG YongMing 2.1 Sichuan University,Chengdu 610065,china 2.State Key Laboratory of Coal resources and Safe {2.,Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete,china University of {2. and technology,Beijing 100083,china 1. Sichuan University Chengdu 610065 China 2. State Key Laboratory of Coal {1. and Safe mining Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete China University of Mining and Technology Beijing 100083 China

The development history and current state of studies on the characteristics and mechanisms of deformation and failure of rock materials were briefly reviewed from the viewpoint of *** main scope and the achievable objectives of the energy-based research system were *** was validated by experiments that the damage process of rocks can be well described by the rock damage evolution equation established based on energy *** was found from the uniaxial compression and biaxial compression tests that only a small proportion of the total input energy in hard rocks is dissipated before peak load and a large proportion in soft rocks is dissipated before peak *** both hard and soft rocks,the energy dissipated after peak load accounts for a greater *** energy would be required for rock failure under equal biaxial compression than under unequal biaxial *** total absorbed energy is different for rock failure under high-rate loading and low-rate *** fragmented failure pattern usually corresponds to higher energy *** mesoscopic analysis on the damage and failure of bedded salt rocks showed that the energy dissipation is prominent and the total absorbed energy for rock failure is low when cracks propagate in the weak mud interlayer while it is contrary when cracks propagate in the salt *** energy accumulation,transfer,dissipation and release during the failure process of tunnel with impending failure under disturbance were analyzed theoretically based on the elastoplastic mechanics ***,the spatial distribution of energy dissipation and energy release of fractured rocks under unloading was simulated *** was demonstrated that energy is likely to be released from the weakest surface under compression,which triggers the global failure of rocks.

关键词： rock deformation failure energy accumulation energy dissipation energy release

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Comparative study on CO_2.corrosion behavior of N80,P1.0,X52.and 1.Cr pipe lines in simulated stratum water

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Science china(Technological Sciences) 2010年第9期53卷 2342-2349页

作者： CAI YiDong1.GUO PengChao1.LIU DaMeng1.CHEN ShiYu2.& LIU JunLai3 1.School of Energy {1.,china University of {2.,Beijing 1.0083,china 2.School of Materials Science and Engineering,University of Science and technology Beijing,Beijing 1.0083,china 3 School of Earth Sciences and {1.,china University of {2.,Beijing 1.0083,china 1. School of Energy resources China University of Geosciences Beijing 100083 China2. School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China3. School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China

To better understand the carbon dioxide (CO2. corrosion behavior of carbon steel and its influence on petroleum development (including drilling,production and transportation) in the Daqing Oilfield,CO2.corrosion behaviors of N80,P1.0,X52.and 1.Cr pipe lines in simulated solution at high temperature and high pressure condition are investigated by dynamic corrosion experiments,scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) *** show that the corrosion rate of all pipe lines increases quickly when CO2.partial pressure increases from 0.5 to 1.5 MPa,but it slows down when CO2.partial pressure further increases from 1.5 to 4.5 MPa,during which localized corrosion is *** the experimental temperature ranges from 60 to 1.0}°C,localized corrosion *** corrosion rate of all pipe lines decreases sharply when the temperature changes from 60 to 1.0°C,and it becomes stable after the temperature is higher than 1.0°*** the flow rate is in the range of 0–1.5 m/s,the corrosion rate of sample X52.remains unchanged,but localized corrosion gradually becomes very serious when the flow rate further *** analyzing the corrosion product scales of sample 1.Cr,some remarkable phenomena are *** the temperature range of 60–1.0°C,the corrosion product scales are loose and thick,but become very compact when the temperature increases above 1.0°*** the later case,localized corrosion is *** main components of the corrosion product scales are FeCO3 and Cr2.3.

关键词： CO2 corrosion pipe lines weight loss SEM EDS

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Influence of valence electron structures of phase and biphase interfaces of sulfides on hot brittleness in steel

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Science china(Technological Sciences) 2004年第4期47卷 488-504页

作者： LIU Yan1.3, LIU Zhilin1. ZHANG Chengwei1.2.& ZHOU Yingchun1.1. Liaoning Institute of {1., Jinzhou 1.0}001. china 2. china National Oil and Gas Exploration and Development Corporation, Beijing 1.001., china 3. college of Science, Northeastern University, Shengyang 1.0006, china 1. Liaoning Institute of technology 121001 Jinzhou China 2. {1. of Science Northeastern University 110006 Shengyang China 3. china National Oil and Gas Exploration and Development Corporation 100011 Beijing China

This paper calculates the electron structures of phase of FeS, MnS and their biphase interface electron structures with austenite in steel. The precipitation and the transformation of FeS and MnS are investigated through studying the valence electron pair numbers on the strongest bond n A with the structure formation factor S. The continuity of electron density and its relation with stress are explored in the biphase interfaces with the electron density difference απ Using n A, S, απ we explain the reason why FeS can bring about hot brittleness in steel and the physical mechanism why MnS may eliminate or inhibit hot brittleness, based on which satisfying results are obtained by calculating several rare-earth sulfides.

关键词： valence electron structure, sulfide, hot brittleness, and rare earth.

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Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science china Earth Sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1., LUO Zhaohua 1., ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3 1. Faculty of Earth Sciences and Natural resources,{1. University of {2., Beijing 1.0083,{1. 2. Faculty of Earth Sciences,{1. University of {2., Wuhan 430074,{1. 3. Beijing SHRIMP Center, Institute of Geology, Chinese Academy of Geological Sciences, Beijing 1.0037,{1. 1. Faculty of Earth Sciences and Natural resources China University of Geosciences 100083 Beijing China 2. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China 3. Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 72. and 773 Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2.68 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

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Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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Wuhan University Journal of Natural Sciences 2002年第1期7卷 107-112页

作者： Zheng Hua 1., Du Yu-min 2.1. Department of Chemical Engineering, Wuhan University of {1., Wuhan 430070, Hubei, china 2. {2. of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072. Hubei, china Wuhan University of technology Department of Chemical Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) Wuhan University College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization

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Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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Science china Earth Sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1.2. TONG Jinnan3, QIU Haiou4 & ZHAO Laishi3 1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 2.0008, china 2. Henan Institute of Geological Survey, Zhengzhou 450007, china 3. State Key Laboratory of Geological Processes and {2. resources at china University of geosciences, Wuhan 430074, china 4. Faculty of Material Sciences and Chemical Engineering, china University of geosciences, Wuhan 430074, china 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan Institute of Geological Survey Zhengzhou 450007 China 3. State Key Laboratory of Geological Processes and mineral {1. at{2. University of geosciences Wuhan 430074 China 4. Faculty of Material Sciences and Chemical Engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 1.C background values are intensively controlled by palaeogeographic environment. In general, δ 1.C values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

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Polycistronic strategy for cyanobacterial expression vector construction: Co-transcription of a human gene and a selective marker gene

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Progress in Natural Science:Materials International 2005年第9期15卷 798-803页

作者： ZHANG Yukun1. SHI Dingji2. ZHAO Feifei1. YU Meimin1.and RU Binggen1.1. {1. of Life Science, Peking University, Beijing 1.0871. china 2. {1. of Marine Sciences & Engineering, Tianjin University of Science & technology, Tianjin 300450, china) college of Life Science Peking University Beijing 100871 China. college of Marine Sciences & Engineering Tianjin University of Science & Technology Tianjin 300450 China

A polycistronic expression vector, pKGA-NTF1. was constructed for the cyanobacterium. Within this vector, the spectinomycin/streptomycin resistance gene (aadA) facilitated the selection of transformants when co-transcribed with favorite genes. A natural glnA gene was selected as the platform to introduce the plasmid into a neutral site of the Synechococcus sp. PCC 7002.chromosome. Function of the vector was demonstrated by the insertion of a modified human Trefoil factor 3 gene (NTF1. to upstream of the aadA gene and by the analyses of the transformed strains. Antibiotics resistance assays showed that the dicistronic expression cassette conferred high spectinomycin resistance to both the E. coli cells and the Synechococcus cells. PCR analysis and Western-blot analysis were carried out to confirm the integration and expression of the NTF1.gene, respectively. Through simple molecular manipulations, the artificial polycistronic structure described here can be conveniently used to express other favorable genes or operons in cyanobacteria, and to study the cyanobacterial gene expression as well.

关键词： cyanobacterial transformation human Trefoil factor 3 polycistronic expression Synechococcus sp. PCC 7002 vector construction.

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