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评“《自然》评出的2012年五大挑战性科学实验” 被引量:5
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作者 李子丰 《中国科技信息》 2012年第18期58-58,共1页
逐条分析了《自然》评出的五项前沿实验:(1)寻找外星生命的"蛛丝马迹",(2)看穿手性分子的"镜像",(3)寻找额外的空间维度,(4)捕捉引力波,(5)对千克进行重新定义。得出了前两个实验是近期不可能实现的伟大理想,后三... 逐条分析了《自然》评出的五项前沿实验:(1)寻找外星生命的"蛛丝马迹",(2)看穿手性分子的"镜像",(3)寻找额外的空间维度,(4)捕捉引力波,(5)对千克进行重新定义。得出了前两个实验是近期不可能实现的伟大理想,后三个是将物理学拉向泥潭的谬论。 展开更多
关键词 自然杂志 外星生命 分子镜像 多维空间 引力波 千克
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Historical Development in Soil Micromorphological Imaging 被引量:2
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作者 A.R.Mermut 《Journal of Mountain Science》 SCIE CSCD 2009年第2期107-112,共6页
The book "micropedolog" by Kubieana and a large number of publications has induced many people to practice soil micromorphology. Quantification of the soil fabric and its components was a major challenge. The use of... The book "micropedolog" by Kubieana and a large number of publications has induced many people to practice soil micromorphology. Quantification of the soil fabric and its components was a major challenge. The use of the image analyses in soil science was a breakthrough. Attempts to make soil thin sections go back to the beginning of the 2oth century. Microscopic techniques and recently high resolution electron microscope and use of computer assisted imaging techniques enabled the in vitro study of soils in three dimensional levels. It is now possible to store and process massive amounts of data. Micro- morphological concepts and techniques are applied in paleopedological, ecological, and archaeological studies. The aim of this work was to examine soil micromorphological imaging in historical perspective. 展开更多
关键词 Soil micromorphology quantification imaging techniques HISTORY
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A mirror-image protein-based information barcoding and storage technology 被引量:1
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作者 Ji-Shen Zheng Jun Liang +4 位作者 Wei-Wei Shi Ying Li Hong-Gang Hu Chang-Lin Tian Lei Liu 《Science Bulletin》 SCIE EI CSCD 2021年第15期1542-1549,M0004,共9页
A mirror-image protein-based information barcoding and storage technology wherein D-amino acids are used to encode information into mirror-image proteins that are chemically synthesized is described.These mirror-image... A mirror-image protein-based information barcoding and storage technology wherein D-amino acids are used to encode information into mirror-image proteins that are chemically synthesized is described.These mirror-image proteins were then fused into various materials from which information-encoded objects were produced.Subsequently,the mirror-image proteins were extracted from the objects using biotin-streptavidin resin-mediated specific enrichment and cleaved using an Ni(Ⅱ)-mediated selective peptide cleavage.Protein sequencing was accomplished using liquid chromatography/tandem mass spectrometry(LC-MS/MS)and then transcoded into the recorded information.We demonstrated the use of this technology to encode Chinese words into mirror-image proteins,which were then fused onto a poly(ethylene terephthalate)(PET)film and retrieved and decoded by LC-MS/MS sequencing.Compared to information barcoding and storage technologies using natural biopolymers,the mirrorimage biopolymers used in our technology may be more stable and durable. 展开更多
关键词 Mirror-image proteins Information barcoding and storage Chemical protein synthesis Protein-of-things Protein sequencing
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Occurrence, Structure and Mineral Phases of Nanoparticles in an Anthrosol
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作者 LU Sheng-Gao SUN Fang-Fang ZONG Yu-Tong 《Pedosphere》 SCIE CAS CSCD 2013年第3期273-280,共8页
Soils contain various kinds of crystalline to amorphous solid particles with at least one dimension in the nanoscale (〈 100 nm). These nanoparticles contribute greatly to dynamic soil processes such as soil genesis... Soils contain various kinds of crystalline to amorphous solid particles with at least one dimension in the nanoscale (〈 100 nm). These nanoparticles contribute greatly to dynamic soil processes such as soil genesis, trace element cycling, contaminant transport, and chemical reaction. The nano-sized fraction of an Anthrosol was obtained to determine the occurrence, chemical composition, structure, and mineral phases of nanoparticles using high-resolution transmission electron microscopy (HRTEM) equipped with an energy-dispersive X-ray spectroscopy. Selected area electron diffraction or the fast Fourier transform of high-resolution images was used in structural characterization of the nanoparticles with HRTEM. Two nanoscale mineral types, i.e., mineral nanoparticles and nanomi- nerals, were observed in the Anthrosol. Mineral nanoparticles in soil included well crystalline aluminumsilicate nanosheets, nanorods, and nanoparticles. Nanosheets with a length of 120-150 nm and a width of about 10-20 nm were identified as chlorite/vermiculite series. The presence of clear lattice fringe spacing in HRTEM image of nanoparticles indicated that mineral nanoparticles had a relatively good crystallinity. The nanomineral ferrihydrite also existed in the Anthrosol. The HRTEM images and the particle size distribution histogram suggested that these ferrihydrite nanoparticles were quite homogeneous, and had a narrow size distribution range (1-7 nm) with a mean diameter of 3.6 4- 1.6 nm. Our HRTEM observation indicated that mineral nanoparticles and nanominerals were common and widely distributed in Anthrosols. HRTEM and selected area diffraction or lattice fringe spacing characterization provided further proofs to the structure of nanoparticles formed in soil. 展开更多
关键词 energy-dispersive X-ray spectroscopy (EDS) FERRIHYDRITE high-resolution transmission electron microscopy (HRTEM) nanominerals nano-sized fraction
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