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Regulation mechanism of EM parameters in natural ferrite and its application in microwave absorbing materials

Science china(Technological sciences) 2006年第1期49卷 38-49页

作者： ZHENG Yongchun1,2. WANG Shijie2. FENG Junming2. LI Chunlai1, OUYANG Ziyuan1,2. LIU Jianzhong1 & LI Xiaobiao2.1. National Astronomical Observatories, chinese academy of sciences, Beijing 100012. china 2. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, chinese academy of sciences, Guiyang 550002. china 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China 2. State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Electromagnetic (EM) parameters (ε ′, ε ″, μ ′, μ″ ) of several M2.Fe2.4 and Fe2.3 type natural ferrites with different geological occurrences are measured in this pa-per. The measurement results show that EM parameters of a magmatic-occurring natural ferrite is very different from other types occurring from sedimentary-metamorphic iron deposit, hydrothermal vein iron deposit, outer contact of magmatic iron deposit. It has potential to be used as magnetic absorbent in microwave absorbing materials. After min-eral separation and concentration, this magmatic-occurring natural ferrite was processed into type A ferrite absorbent. Type A natural ferrite absorbent is a kind of magnetic material with low dielectric constants, high magnetic conductivity and high EM loss. Its EM pa-rameters are ε ′ = 58.60, ε ″ = 10.0, μ ′ = 1.2.1.5, μ ″ = 1.0-1.2. respectively. In order to illuminate the regulation mechanism of EM parameters, we studied the chemical and mineral composition of type A ferrite absorbent. There is high concentration of natural impurities, which regulate the EM parameters of type A ferrite greatly. For comparison, the other types of natural ferrite, single-phase magnetite and two-phase iron minerals (ilmen-ite and magnetite), have few impurity. Thus regulation mechanism of EM parameters was absent in these ferrites. As a result, the regulation of EM parameters is advantageous to develop type A natural ferrite as excellent absorbent, lowers the reflectivity coefficients and enhances the absorbing efficiency of MAM made from it. Furthermore, the impurities in type A natural ferrite and its effects on EM parameters are very difficult to simulate in the synthesize ferrite. The carbonyl-iron powder is another kind of absorbent that is used ex-tensively in MAM. To compare the absorbing properties of these two absorbent, type A natural ferrite and carbonyl-iron powder were mixed with rubber and processed into mi-crowave absorbing sheets with the same procedures and tec

关键词： natural impure ferrite, complex permittivity, complex permeability, microwave absorbing materials.

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Science china Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. Department of Chemistry, Nanjing University of Science and Technology, Nanjing 2.0094, china 2. Institute of chemical Materials, china academy of Engineering physics, Mianyang 62.900, china 1. Department of Chemistry Nanjing University of Science and Technology 210094 Nanjing China 2. Institute of chemical Materials China Academy of Engineering Physics 621900 Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

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On-line parallel reversed phase two-dimensional liquid chromatography for high-throughput analysis of complex proteomic samples

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Science china Chemistry 2006年第6期49卷 527-533页

作者： WANG Zhicong1,3, ZHANG Qinghe2. LI Tong2. ZHAO Zhongyi3 & ZHANG Weibing1 1. Dalian Institute of chemical physics, {2., Dalian 116011, china 2. Dalian Elite Analytical Instrument Co., Ltd., Dalian 116011, china 3. Faculty of Material Science and chemical Engineering, china University of Geosciences, Wuhan 430074, china 1. Dalian Institute of chemical physics Chinese Academy of Sciences Dalian 116011 China 3. Faculty of Material Science and chemical Engineering China University of Geosciences Wuhan 430074 China 2. Dalian Elite Analytical Instrument Co. Ltd. Dalian 116011 China

A comprehensive two-dimensional liquid chromatographic system (2. SCX/RP) is con- structed with a 10-port-2.way valve using strong cation exchange chromatography (Hypersil SCX, 100 mm×4.6 mm I.D.) followed by reversed phase chromatography (Hypersil BDS C18, 15 mm×4.6 mm I.D.) to separate the complex peptides from globin peptic hydrolysate. After the sample was loaded on the SCX column, the phosphate buffer (pH 4.0) was used to elute the peptides. Then, elutes flowed through the interface and the peptides focused on the head of the trapping columns (Hypersil BDS C18, 15 mm×4.6 mm I.D.) but salt passed into the waste. After the valve was switched, the samples were flushed with a backward flow into the RP analytical column. The peptides on the SCX were eluted with 12.discontinuous steps linearly increasing salt concentrations. The peptides enriched on the trapping column were desalted and separated by the RP columns. The resolution and the resolved peaks of the 2. SCX/RP system were greatly increased and the total peak capacity reached as high as 2.80.

关键词： two-dimensional liquid chromatography, interface, trapping column, proteomics, globin.

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Gymnosperms on the eve of the terminal Permian mass extinction in North china and their survival strategies

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chinese Science Bulletin 1998年第11期43卷 889-897页

作者： WANG Ziqiang+1 and ZHANG Zhiping+2. 1. Tianjin Institute of Geology and Mineral Resources, chinese academy of Geological {2., Tianjin 300170, china 2. Tianjin Centre of Physical and chemical Techniques, Tianjin 300050, china Tianjin Institute of Geology and Mineral Resources Chinese Academy of Geological Sciences Tianjin China Tianjin Centre of Phyhical and chemical Techniques Tianjin China

Main characteristics of the Permian redbed gymnosperms in North china have been summarized: dominant peltasperms and conifers, numerous enigmatics such as Gigantonoclea and Psygmophyllum, and abundant precursors of Mesozoic gymnosperms. Furthermore, stresses affecting these plants survival are suggested to be paleoatmospheric CO-2.concentration, water stress, wind and fire activities, and fungal infection. Consequently, a preliminary analysis accounts for the ecological strategies of these gymnosperms to the P-Tr event.

关键词： North china Permian gymnosperms mass extinction.

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Hydrocarboxylation of Styrene in Water-Soluble Catalyst System Pd(OAc)2.TPPTSH-HOAc-H2.

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分子催化 1997年第2期 2-3页

作者： XIE Baohan KOU Yuan * YINGYuanqi (State Key Laboratory for Oxo Synthesis and Selective Qxidation lanzhou Institute of chemical {2. The chinese academy of sciences lanzhou 730000)

ＨｙｄｒｏｃａｒｂｏｘｙｌａｔｉｏｎｏｆＳｔｙｒｅｎｅｉｎＷａｔｅｒ┐ＳｏｌｕｂｌｅＣａｔａｌｙｓｔＳｙｓｔｅｍＰｄ（ＯＡｃ）２┐ＴＰＰＴＳＨ┐ＨＯＡｃ┐Ｈ２ＯＸＩＥＢａｏｈａｎＫＯＵＹｕａｎ＊ＹＩＮＧＹｕａｎｑｉ（... 详细信息

ＨｙｄｒｏｃａｒｂｏｘｙｌａｔｉｏｎｏｆＳｔｙｒｅｎｅｉｎＷａｔｅｒ┐ＳｏｌｕｂｌｅＣａｔａｌｙｓｔＳｙｓｔｅｍＰｄ（ＯＡｃ）２┐ＴＰＰＴＳＨ┐ＨＯＡｃ┐Ｈ２ＯＸＩＥＢａｏｈａｎＫＯＵＹｕａｎ＊ＹＩＮＧＹｕａｎｑｉ（ＳｔａｔｅＫｅｙＬａｂｏｒａｔｏｒ...

关键词： Hydrocarboxylation Styrene Water soluble catalyst Palladium acetate

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HYDROFORMYLATION OF ETHYLENE CATALYZED BY HOMOGENEOUS METAL CLUSTERS

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分子催化 1989年第S1期3卷 88-93页

作者： Fu Hongxiang, Luo Yuzong , Zhang Shuwei, Ren Xu (lanzhou Institute of chemical {2., chinese academy of sciences, lanzhou, china)

This paper deals with a study of hydroformylation of ethylene catalyzed by homoge-neous metal clusters.〔PhCH2.e3N〕〔FeCo3（CO）12.and〔PhCH2.e3N〕〔RuCO3（CO）12.show high catalytic activity for the hydroform ylat... 详细信息

This paper deals with a study of hydroformylation of ethylene catalyzed by homoge-neous metal clusters.〔PhCH2./sub>Me3N〕〔FeCo3（CO）12./sub>〕and〔PhCH2./sub>Me3N〕〔RuCO3（CO）12./sub>〕show high catalytic activity for the hydroform ylation of ethylene compared with YCCo3（CO）9,CO4（CO）10（PPh）2./sub>,Co2./sub>（CO）6（PBu3）2./sub>,and Fe2./sub>（CO）4（C5H5）2./sub>.The reacton rate ofheteronuclear clusters is faster than that with homonuclear *** effect of tempera-ture and pressure on hydroformylation of ethylene with〔PhCH2./sub>Me3〕〔FeCo3（CO）12./sub>〕ascatalyst was *** experimental *** that the conversion of ethylene exceeds90% with a selectivity up to 95% at temperature 130℃ and pressure 3.9 *** studiedwith high pressure in situ infrared spectroscopic method,PhCCo3（CO）9 was found to havehigher thermostability than 〔PhCH2./sub>Me3N〕〔FeCo3（CO）12./sub>〕.

关键词： FeCo faster selectivity tempera spectroscopic crystalline catalyzed silica deals carbonyl

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Effects of diatoms on reproduction and growth of marine copepods

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Progress in Natural Science:Materials International 2004年第10期14卷 1-7页

作者： ZHANG Guangtao 1,2. and SUN Song 1 (1.Key Laboratory of Marine Ecology&Environment sciences,Institute of Oceanology,chinese academy of sciences,Qingdao2.6071,{2. 2.Graduate School,chinese academy of sciences,Beijing100039,{2.) chinese Acad Sci Inst Oceanol Key Lab Marine Ecol & Environm Sci Qingdao 266071 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China

Two hot spots in marine ecology,deleterious effects of diatoms and feeding selectivity of copepods,as well as new progress on these two issues achieved in the recent ten years,are *** two issues are considered correlated *** and their metabolites can induce deleterious effects on growth,reproduction and development of copepods,including increase of mortality and decrease of egg production,hatching and growth *** negative effects,resulting from either chemical toxin or nutritional defi-ciency,can be conquered in natural environments by diverse *** is therefore concluded that deleterious effects of diatoms observed in laboratory or during blooming period are only a special case that accommodation of feeding strategy of copepods is *** under-stand their feeding strategy in natural environments is a prerequisite to explaining the mechanisms of deleterious effects caused by diatoms,and makes it possible to re-evaluate the energy flow in marine ecosystems.

关键词： diatoms copepod feeding strategy reproduction deleterious effects

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Microcosmic analysis of ductile shearing zones of coal seams of brittle deformation domain in superficial lithosphere

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Science china Earth sciences 2004年第5期47卷 393-404页

作者： JU Yiwen1,2. WANG Guiliang2. JIANG Bo2.& HOU Quanlin1 1. Graduate School, chinese academy of sciences, Beijing 100039, china 2. College of Mineral Resources and Geo{2., china University of Mining & Technology, Xuzhou 2.1008, china chinese Acad Sci Grad Sch Beijing 100039 Peoples R China china Univ Min & Technol Coll Mineral Resources & Geosci Xuzhou 221008 Peoples R China

The ductile shearing zones of coal seams in a brittle deformation domain in super-ficial lithosphere are put forward based on the study on bedding shearing and ductile rheology of coal seams. The macrocosmic and microcosmic characteristics include wrinkle fold, mymonitized zones and ductile planar structure of coal seams, etc., while the microcosmic characteristics may also include different optic-axis fabrics and the anisotropy of vitrinite reflectance as well as the change of chemical structure and organic geochemistry components. The forming mechanism is analyzed and the strain environment of ductile shearing zones of coal seams discussed. The result indicates that, in the superficial brittle deformation domain, the coal seams are easy to be deformed, resulting in not only brittle deformation but also ductile shearing deformation under the action of force. Because of simple shearing stress, the interlayer gliding or ductile rheology may take place between coal seams and wall rocks. Therefore, many ductile shearing zones come into being in superficial lithosphere (<5 km). The research on ductile shearing zone of brittle de-formation domain in superficial lithosphere is significant not only theoretically for the study of ductile shearing and ductile rheology of the lithosphere but also practically for the structural movement of coal seams, the formation and accumulation of coal-bed methane, and the preven-tion and harness of gas burst in coal mine.

关键词： brittle deformation domain, interlayer gliding, ductile rheology, ductile shearing zones of coal seams, coal mymonite, vitrinite reflectance anisotropy.

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A New Bianthraqinonc Glycoside from Eremurus chinensis

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chinese chemical Letters 2000年第2期11卷 135-138页

作者： Jian Gong SHI1 Chong LI2.Ying Peng ZHANG2.Cheng Zhong ZHANG2.(1Institute of Materia Medica, chinese academy of Medical {2. and Peking Union Medical, College, Beijing, 100050 2.epartment of Pharmacy, lanzhou Medical College, lanzhou 730000) Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China Department of Pharmacy Lanzhou Medical College Lanzhou 730000 China

A new bianthraquinone glycoside, 8-O-β-D-glucopyranosyl-2.7'-bi(1,8-dihydroxy-3- methyl-9, 10-anthraquinonyl)1 was isolated from Eremurus chinensis Fedtch. Its structure was established by spectroscopic techniques in... 详细信息

关键词： Eremurus chinensis Liliaceae bianthraquinone glycoside.

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Synthesis and Characterization of PEG-like Structures on Nitinol Surface under ECR-cold-plasma

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Journal of Wuhan University of Technology(Materials Science) 2005年第1期20卷 33-36页

作者：杨隽 Institute of Plasma physics Chinese Academy of Sciences Anhui 230031 China School of Materials Science and Engineering Wuhan Institute of Chemical Tech nologyWuhan 430073China

The synthesis and characterization of PEG-like macromolecular structures on Nit inol surface from tri (ethylene glycol) dimethyl-ether under ECR-cold-plasma conditions were discussed. It was demonstrated that based on high-resolution ES CA, ATR-FTIR and contact angle investigations, the deposited PEG-like layers a re composed mainly of -CH 2.CH 2.O- linkages. These structures have a relati vely low contact angle. Compared to the unmodified surfaces, the plasma-treated Nitinol surfaces are more hydrophilic. Plasma enhanced coatings of PEG-like la yers can prevent Ni ion from releasing, thereby improving the biocompatibility o f Nitinol.

关键词： cold-plasma Nitinol modification PEG-like s tructures

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