363 resultados para Encyclopedias and dictionaries, Chinese


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Magnetic microsphere comprises a magnetically responsive metal or metal oxide core surrounded by a polymer shell with active groups. Nowadays, methods of directly coating polymer, monomer polymerazation, impregnation, extrusion and biological synthesis are generally used to prepare magnetic particles. This kind of superparamagnetic microspheres can be attached to chemical, biochemical and biological substances by their active groups, then applying a magnetic field to separate from the media. Preparation and utilization of magnetic microspheres in immunoassay, nucleic acid hybrization assay, gene sequencing, cell isolation, enzyme immoblization, receptor isolation and other Gelds are reviewed with 44 references in this paper. Also, the further development is outlooked.

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Ephedrine and isoephedrine were first distingshed by electrospy ionization mass spectrometry and in-sourice collision-induced dissociation technique. Based on this observation, a unkown sample was identified for ephedrine.

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Tb(111) and Ca(11) ion equilibria in the Presence of glutamic acid and glutamine were studied by potentiometric titration at 37 degrees C and an ionic strength of 0.15mol/L(NaCl). The stability constants for Tb(111) and Ca(11) complexes in the systems were obtained. The species and their distribution in the systems were discussed.

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Monolayers of porphyrin and phthalocyanine at the air-water interface were studied by means of film balance and Brewster angle microscopy (BAM). Results showed that the final point of compression isotherm and that of recompression isotherm were coincident or not coincident depending on the target pressures. Results were discussed in terms of the morphology of monolayers observed by BAM.

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A novel in-situ spectroelectrochemical technique, the combination of probe beam deflection (PBD) with cyclic voltammetry (CV), was used to study the ion exchange process of prussian blue(PB) modified film electrode in contact with various electrolyte solutions. The ion exchange mechanism was verified as following: (K2Fe2+FeII)(CN)(6) -e(-)-k(+)reversible arrow +e(-)+k(+) (KFe3+FeII)(CN)(6) -ke(-)-xk(+)reversible arrow +xe(-)+kk(+) [(Fe3+FeIII)(CN)(6)](x)[(KFe3+FeII)(CN)(6)](1-x) where on reduction PB film in contact with an acidic KCl electrolyte, it was confirmed that protons enter into the PB film before K+ cations.

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Algae have been part of Chinese life for thousands of years. They are widely used as food and have been cited in Chinese literature as early as 2500 years ago. However, formal taxonomic studies on Chinese algae were initiated by foreign scientists only about 200 years ago, and by Chinese phycologists only about 90 years ago. This paper summarizes the history of modern phycological studies on Chinese algae and provides an overview of the achievements of phycological studies by Chinese scientists, especially on algal taxonomy, morphology, genetics, ecology and environmental research, physiology, biotechnology, algal culture, applied phycology and space phycology, in the last century. Recent development in phycological research focuses on algal floristic and molecular systematics, algal molecular biotechnology, applied phycology including micro and macroalgal cultivation and algal product development, and the roles of algae in environmental pollution control. These areas will also be the main focuses of Chinese phycological research in the foreseeable future.

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The general forms of the conservation of momentum, temperature and potential vorticity of coastal ocean are obtained in the x-z plane for the nonlinear ocean circulation of Boussinesq fluid, and a elliptic type partial differential equations of second order are derived. Solution of the partial differential equations are obtained under the conditions that the fluid moves along the topography. The numerical results show that there exist both upwelling and downwelling along coastline that mainly depends on the large scale ocean condition. Numerically results of the upwelling (downwelling), coastal jet and temperature front zone are favorable to the observations.

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Direct current observations in the Yellow Sea interior are very scarce due to intense fishing and trawling activities. Most previous studies on tides in the area were based on coastal measurements or satellite altimeter sea levels and have not been rigorously compared with direct measurements. In this paper, tidal currents are studied with current profiles from three bottom-moored Sontek Acoustic Doppler Profilers (ADPs) deployed in the southern Yellow Sea in summer of 2001 and 2003. The measured current series were dominated by tidal currents. Maximum velocities are between 40-80 cm/s at the mooring stations. M-2 current is the most dominant primary tidal constituent, while MS4 and M-4 are the most significant shallow water tides with much smaller amplitudes than the primary tides.

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The frequency and scale of Harmful Algal Bloom (HAB) and marine algal toxin incidents have been increasing and spreading in the past two decades, causing damages to the marine environment and threatening human life through contaminated seafood. To better understand the effect of HAB and marine algal toxins on marine environment and human health in China, this paper overviews HAB occurrence and marine algal toxin incidents, as well as their environmental and health effects in this country. HAB has been increasing rapidly along the Chinese coast since the 1970s, and at least 512 documented HAB events have occurred from 1952 to 2002 in the Chinese mainland. It has been found that PSP and DSP toxins are distributed widely along both the northern and southern Chinese coasts. The HAB and marine algal toxin events during the 1990s in China were summarized, showing that the HAB and algal toxins resulted in great damages to local fisheries, marine culture, quality of marine environment, and human health. Therefore, to protect the coastal environment and human health, attention to HAB and marine algal toxins is urgently needed from the environmental and epidemiological view.

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Paraprionospio pinnata (Ehlers, 1901), a poorly known and potentially cosmopolitan polychaete, was examined from museum specimens and from collections in Jiaozhou Bay, the Yellow Sea. New observations indicate that previous Chinese records of P. pinnata are doubtful, and that Chinese waters contain at least three valid species of Paraprionospio, two are known and one is new. Paraprionospio inaequibranchia (Caullery, 1914) and Paraprionospio coora Wilson, 1990, previously misidentified as P. pinnata, are reported from Chinese waters for the first time. Paraprionospio crist'ata. new species, is characterized by having brown pigment patches on the prostomium, ventral crests on chaetigers 9 and 10, dorsal crests on the middle part of the body (from chaetigers 21-23, not beyond chaetiger 29). thin filaments on chaetiger 3, and bifoliate branchial lamellae.

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In this paper, a ground hydrologic model(GHM) is presented in which the vapor, heat and momentum exchanges between ground surface covers (including vegetation canopy) and atmosphere is described more realistically. The model is used to simulate three sets of field data and results from the numerical simulation agree with the field data well. GHM has been tested using input data generated by general circulation model (GCM) runs for both the North American regions and the Chinese regions, The results from GHM are quite different from those of GHMs in GCMs. It shows that a more active concerted effort on the land surface process study to provide a physically realistic GHM for predicting the exchange between land and atmosphere is important and necessary.

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釉砂和玻砂是古玻璃的前身,和古玻璃相比有着不同的成分组成和化学结构.考古资料显示中国釉砂和玻砂的持续时间自西周初期至东汉时期.用质子激发X荧光技术和电感耦合等离子体发射光谱分析了几个出土于中国内蒙古、甘肃、河南的釉砂和玻砂管珠的化学成分.用X射线衍射和扫描电镜测定样品的显微形貌.结合已经报道的釉砂和玻砂的化学成分,探讨了釉砂、玻砂的现代科技鉴定方法以及对古玻璃研究的重要意义.同时,还讨论了中国釉砂与古埃及釉砂的成分差异,论证了中国古代釉砂的自主生产特征.

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Partial sequences of the mitochondrial cytochrome b gene of the Korean hare (Lepus coreanus) were analyzed to determine the degree of genetic diversity. Nine haPlotyes were observed, and the maximum Tamura-Nei nucleotide distance among them was 2.8%, indicating that genetic diversity of L. coreanus is moderate. In order to clarify the Korean hare's taxonomic status and relationship with the Manchurian hare (L. mandshuricus) and the Chinese hare (L. sinensis), these nine haplotypes of the Korean hare were compared with 13 haplotypes from five other species of eastern Asian Lepus including L. mandshwicus and L. sinensis. The Korean hare was distinct in its cytochrome b gene, and it is confirmed that L. coreanus is a valid species, as noted by Jones and Johnson (1965, Univ. Kansas Publ. (Mus. Nat. Hist.) 16:357). Further analyses of mtDNA cytochrome b gene with additional specimens of L. coreanus from North Korea and other species of Lepus from eastern Asia are needed to clarify the taxonomic status of the divergent mtDNA clades of L. mandshuricus and L. sinensis.