检索结果-南通市图书馆

维普期刊数据库

nanoscale control of silks for regular hydroxyapatite formation

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2012年第2期22卷 115-119页

作者： Xingliang He a,Xiaowei Huang b,Qiang Lu b,Shuling Bai a,Hesun Zhu c a College of Basic Medical Science,chinese Medical University,Shenyang 110001,People’s Republic of china b National Engineering laboratory for Modern Silk,College of Textile and Clothing Engineering,Soochow University,Suzhou 215123,People’s Republic of china c Research Center of Materials Science,beijing Institute of Technology,beijing 100081,People’s Republic of china College of Basic Medical Science Chinese Medical University Shenyang 110001 People's Republic of China National Engineering laboratory for Modern Silk College of Textile and Clothing Engineering Soochow University Suzhou 215123 People's Republic of China Research Center of Materials Science Beijing Institute of Technology Beijing 100081 People's Republic of China

The control of nanoparticle shape is still a challenge for different hydroxyapatite(HA) preparation *** the present study,silk fibroin with regular nanostructures was firstly prepared and then employed to regulate the mineralization of HA *** morphology and crystal structure of the deposition were investigated by SEM,X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR).Compared to previous studies in which silk fibroin with different nanostructures was used as template,the present study revealed that the HA nanoparticle shape could be controlled through regulating the nanostructure of silk *** silk nanospheres as template,the shape of HA gradually changed from pin-like structure to rice-like structure following the increase of silk fibroin *** some HA nanofibers were prepared with short silk nanofibers as *** results indicated that it is feasible to achieve the shape control of HA nanoparticles through further regulating the nanostructure of silk fibroin template,which would greatly facilitate the application of HA in different fields.

关键词： Silk fibroin Hydroxyapatite Shape control biomineralization

nanostructure of Nacre and Its Mechanical Effects

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nanostructure of Nacre and Its Mechanical Effects

2002年微纳米国际会议

作者： Fan Song and Yilong BaiState Key laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics chinese Academy of Sciences beijing 100080 china

＜正＞ A type of nanostructure in the organic matrix interfaces of nacre, which is referred to as mineral bridge in the biomineralization, is directly observed with a transmission electron microscope. It is showed that the existence of mineral bridges in nacre is confirmed. Statistical analysis gives the geometrical characteristics and distribution law of the nanostructure in the organic matrix interfaces. Mechanical experiments and analyses demonstrate that mineral bridges play a key role in mechanical properties of nacre. The nanostructure can not only effectively increase the crack resistance of the organic matrix interfaces, but also automatically form periodic crack resistance to prevent cracks from extending in nacre. This is an indication that the microarchitecture of nacre should be referred to as a “brick-bridge-mortar”arrangement rather than traditional “brick and mortar”one, which gives a conceptual guide to the biomimetic design of synthetic materials.

关键词： nanostructure mineral bridges nacre mechanical properties

Growth of Hydroxyapatite Crystal in the Presence of Origanic Film

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2004年第2期20卷 223-226页

作者： Yong LIU, Suping HUANG, Xiaohong DAN and Kechao ZHOUState Key laboratory for Powder Metallurgy, Central South University, Changsha 410083, china Lab. for Powder Metall. Central South Univ. Changsha 410083 China

The growth of hydroxyapatite (HAp) crystal in the presence of hexadecylamine was investigated. Due to its high polarity and high charge density, the organic film could increase the ion supersaturation on its surface. Therefore the growth of pure HAp crystals was accelerated. Moreover, the positive headgroups of the organic film could act as recognized nucleation sites and orient the growth of HAp crystals along the direction.

关键词： biomineralization Hydroxyapatite Crystal growth

维普期刊数据库

Mineralogical and geochemical evidence for coupled bacterial uranium mineralization and hydrocarbon oxidation in the Shashagetai deposit,NW china

在线全文

学校读者我要写书评

暂无评论

Mineralogical and geochemical evidence for coupled bacterial...

中国科学院地质与地球物理研究所2006学术年会

作者： Chunfang Cai~1,Hailiang Dong~2,Hongtao Li~1,Xinjian Xiao~3,Guanxi Ou~3, Chunming Zhang~4 1 Key laboratory of Mineral Resources,Institute of Geology and Geophysics,chinese Academy of Sciences,P.O. Box 9825,Beitucheng Xilu No.19,beijing 100029,P.R.china 2 Department of Geology,Miami University,Oxford,OH 45056,USA 3 beijing Research Institute of Uranium Geology,beijing 100029,P.R.of china 4 Department of Geochemistry,Yangtze University,Jingzhou,Hubei 434023,PR china

Unusual mineral structures have recently been found in a sandstone-hosted roll-type uranium deposit in the Middle Jurassic Zhiluo Formation in the Shashagetai deposit,the northern Ordos basin,NW *** structures possess a chemical composition and crystal structure characteristic of mineral coffinite[(USiO)](OH)],which occurs as nanoparticles with size ranging from 5 to *** structures are interpreted to be fossilized microorganisms,based on mineralogical biosignatures including morphology,size,occurrence of biogenic coffinite as nano-crystals,and biological elements such as *** intimate intergrowth of coffinite with secondary pyrite of bacterial origin,as defined by lowδS values,and calcite cements with petroleum-derived carbon supports its biogenic *** inclusions in the host sandstone are characterized by abundant n-alkanes,slightly increased Pr/nC and Ph/nC ratios,significant amounts of demethylated hopanes and tricyclic terpanes,and the existence of unresolved complex *** characteristics are interpreted to be a result of mixing of an earlier,heavily degraded oil with a later charged fresh oil;subsequently the oils were slightly *** lines of evidence lead to the proposal that the reduction of sulfate and oxidization of petroleum are likely synchronous with reduction of hexavalent[U(Ⅵ)]to tetravalent[U(Ⅳ)]uranium by sulfate-reducing bacteria(SRB).The discovery of a natural association of microorganism-like structures,a uranium mineral,and biodegraded petroleum has implications for uranium biomineralization and fossil fuel exploration.

关键词： uranium deposit anaerobic petroleum oxidation sulfate-reducing bacteria nanoparticle microfossil sulfur isotopes

The occurrence of the genus Marrella(Trilobitoidea) in Asia

在线全文

cnki会议

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2003年第9期 70-73页

作者： ZHAO Yuanlong, YUAN Jinliang, ZHU Maoyan, YANG Xinglian and PENG Jing (1. Institute of Palaeontology and biomineralization, School of Resource and Environment, Guizhou University of Technology, Guiyang 550003, china 2. Nanjing Institute of Geology and Palaeontology, chinese Academy of Sciences, Nanjing 210008, china) Institute of Palaeontology and biomineralization School of Resource and Environment Guizhou University of Technology Guiyang 550003 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

An important discovery in the Kaili Biota has been made recently, and many interesting components from ChengjiangBiota and Burgess Shale Biota have been discovered. Among them Marrella, only known from mid-Middle Cambrian Burgess Shale Biotaof British Columbia, Canada, is one of the most important arthropods fossils. Because the Kaili Biota is older than the Burgess Shale Biota,the strange head shield of Marrella occurring in the Kaili Biota outside Laurentia ranges from mid-Middle Cambrian to early Middle Cam-brian and is significant for the reconstruction of palaeogeography and evolutionary study of early metazoa. In the present paper Marrellasp. is reported for the first time in Asia.

关键词： Marrella early Middle Cambrian Kaili Biota Asia.

biomineralization of Calcium Carbonate for Controlling Crystal Structure and Morphology via the Hard Template

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Biomineralization of Calcium Carbonate for Controlling Cryst...

The 3rd International Conference of Bionic Engineering(ICBE’10)

作者： Tianhua Chen1 2 Zhiwu Han1 1 Key laboratory of Bionic Engineering (Jilin University) Ministry of Education P.R.china 2 Mechanical Engineering Academy ChangChun University Changchun 130022 china

Based on the basic principles of biomineralization, aragonite/vaterite calcium carbonate （CaCO3） material with a specific morphology were synthesized by biomimetic method under ambient *** our experiments,the Au, Si substrate were used as the template. The obtained composite CaCO3 were characterized by using X-ray powder diffraction （XRD） analysis and scanning electron microscopy （SEM） and Fourier transform infrared spectroscopy （FTIR） measurement. The results showed that the hard templates can also influence the polymorphism and morphology of crystals as the soft templates. When the CaCO3 induced by the Si substrate, the aragonite polymorph forms;while induced by the Au substrate, vaterite crystals are obtained. At the same time,the possible mechanism of interaction between substrate and CaCO3 during the CaCO3 formation process was *** Si substrate, as negative template, the electrostatic interaction is main factor responsible for the controlled crystallization of CaCO3 on template. For Au substrate, the lattice matching factor plays great role in the crystallized vaterite crystal.

关键词： biomineralization Calcium Carbonate Polymorph hard template

Mineralogical and geochemical evidence for coupled bacterial uranium mineralization and hydrocarbon oxidation in the Shashagetai deposit,NW china

在线全文

cnki会议

学校读者我要写书评

暂无评论

Mineralogical and geochemical evidence for coupled bacterial...

中国科学院地质与地球物理研究所2007学术年会

作者： Chunfang Cai~(a,*),Hailiang Dong~b,Hongtao Li~a,Xinjian Xiao~c, Guanxi Ou~c,Chunming Zhang~d a Key laboratory of Mineral Resources,Institute of Geology and Geophysics,chinese Academy of Sciences,P.O.Box 9825, Beitucheng Xilu No.19,Chaoyang District,beijing 100029,PR china b Department of Geology,Miami University,Oxford,OH 45056,USA c beijing Research Institute of Uranium Geology,beijing 100029,PR china d Key laboratory of Exploration Technologies for Oil and Gas Resources(Yangtze University),Ministry of Education, Jingzhou,Hubei 434023,PR china

Unusual mineral structures have recently been found in a sandstone-hosted roll-type uranium deposit in the Middle Jurassic Zhiluo Formation in the Shashagetai deposit,the northern Ordos basin,NW *** structures possess a chemical composition and crystal structure characteristic of mineral coffinite[(USiO)(OH)],which occurs as nanoparticles with size ranging from 5 to 25 *** structures are interpreted to be fossilized microorganisms,based on mineralogical biosignatures including morphology,size,occurrence of biogenic coffinite as nano-crystals,and biological elements such as *** intimate intergrowth of coffinite with secondary pyrite of bacterial origin,as defined by lowδS values,and calcite cements with petroleum-derived carbon supports its biogenic *** inclusions in the host sandstone are characterized by abundant n-alkanes,slightly increased Pr/nC and Ph/nC ratios,significant amounts of demethylated hopanes and tricyclic terpanes,and the existence of unresolved complex *** characteristics are interpreted to be a result of mixing of an earlier,heavily degraded oil with a later charged fresh oil;subsequently the oils were slightly *** lines of evidence lead to the proposal that the reduction of sulfate and oxidization of petroleum are likely synchronous with reduction of hexavalent[U(Ⅵ)]to tetravalent[U(Ⅳ)]uranium by sulfate-reducing bacteria(SRB).The discovery of a natural association of microorganism-like structures,a uranium mineral,and biodegraded petroleum has implications for uranium biomineralization and fossil fuel exploration.

关键词： Uranium deposit Anaerobic petroleum oxidation Sulfate-reducing bacteria nanoparticle Microfossil Sulfur isotopes

Progress and significance in research on the early Middle Cambrian Kaili Biota, Guizhou Province, china

在线全文

cnki会议

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2002年第9期 11-16页

作者： ZHAO Yuanlong, YUAN Jinliang, ZHU Maoyan, YANG Ruidong, GUO Qingjun, PENG Jin and YANG Xinglian(1. Institute of Paleontology and biomineralization, School of Resource and Environment, Guizhou University of Technology, Guiyang 550003, china: 2. Nanjing Institute of Geology and Paleontology, chinese Academy of Sciences, Nanjing 210008, china 3. Guiyang Institute of Geochemistry, chinese Academy of Sciences, Guiyang 550003, china) Institute of Paleontology and biomineralization School of Resource and Environment Guizhou University of Technology Guiyang 550003 China Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Guiyang Institute of Geochemistry Chinese Academy of Sciences Guiyang 550003 China

Important progress in research on the Kaili Biota has been made recently. Many interesting components from Chengjiang Biota and Burgess Shale Biota have been discovered, e. g. Microdictyon of lobopodia; Ottaia, Palaeoscolex of worms; Naraoia, Marrella of Trilobitioidea, Mollisonia, anamalocarids and other non-trilobite arthropods; and new sorts of echinoder-mas, macroalage fossils and so on. Recent work on the Kaili Biota has resulted in the following developments: (i) an increase in the number of animal genera, up to more than 100 genera in total, so that the Kaili Biota has become the third most diverse of the Burgess Shale-type Biota after the Burgess Shale and Chengjiang Biotas ; and (ii) the most noteworthy fossils in the Kaili Biota are echinoderms, non-trilobite arthropods and soft-bodied medusiform fossils, especially the most diverse echinoderms. The progress provides envidence for the biodiversity of marine organisms presented after the "Cambrian Explosion" and serves as a link between the ear

关键词： Kaili Biota three biotas biodiversity.

Simultaneously inducing synthesis of semiconductor selenium multi-armed nanorods and nanobars through bio-membrane bi-templates

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Chemistry 2004年第6期47卷 507-511页

作者： LI Li1, WU Qingsheng1 DING Yaping2 & LI Ping3 1. Department of Chemistry, Tongji University, Shanghai 200092, china 2. Department of Chemistry, Shanghai University, Shanghai 200436, china 3. Department of Food, Anhui Agricultural University, Hefei 230036, china Department of Chemistry Tongji University Shanghai 200092 China

Multi-armed nanorods and nanobars of semiconductor selenium were simultane- ously synthesized in the light of biomineralization process through bio-membrane bi-templates of rush at room temperature. The multi-armed nanorods are 60 nm in diameter and 1.5 μm in length; the nanobars are 150 nm in diameter and 1000—1100 nm in length. The XRD pattern indicates that these nanocrystals were crystallized in the hexagonal structure with lattice constants a = 0.437 nm, c = 0.495 nm. The possible formation mechanism was investigated.

关键词： selenium, multi-armed nanorods, nanobars, bio-membrane, bi-templates.

维普期刊数据库