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Investigation of changes in properties of water under the action of a magnetic field

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science china(Physics,Mechanics & Astronomy) 2008年第11期51卷 1621-1632页

作者： PANG XiaoFeng1,2 & DENG Bo1 1 Institute of life science and technology, university of Electronic science and technology of china, Chengdu 610054, china 2 International Centre for Materials Physics, Chinese academy of sciences, Shenyang 110015, china Institute of life science and technology University of Electronic Science and Technology of China Chengdu China International Centre for Materials Physics Chinese Academy of Sciences Shenyang China

The properties of water and their changes under the action of a magnetic field were gathered by the spectrum techniques of infrared, Raman, visible, ultraviolet and X-ray lights, which may give an insight into molecular and atomic structures of water. It was found that some properties of water were changed, and a lot of new and strange phenomena were discovered after magnetization. Magnetized water really has magnetism, which has been verified by a peak shift of X-ray diffraction of magnetized water + Fe3O4 hybrid relative to that of pure water + Fe3O4 hybrid, that is a saturation and memory effect. The properties of infrared and ultraviolet absorptions, Raman scattering and X-ray diffraction of magnetized water were greatly changed relative to those of pure water; their strengths of peaks were all increased, the frequencies of some peaks did also shift, and some new peaks, for example, at 5198, 8050 and 9340 cm?1, occurred at 25°C after water was magnetized. In the meanwhile, the magnetized effects of water are related to the magnetized time, the intensity of an externally applied magnetic field, and the temperature of water, but they are not a linear relationship. The study also showed a lot of new and unusual properties of magnetized water, for example, the six peaks in 3000–3800 cm?1 in infrared absorption, the exponential increase of ultraviolet absorption of wave with the decreasing wavelength of light of 200–300 nm, the frequency-shifts of peaks, a strange irreversible effect in the increasing and decreasing processes, as well as a stronger peak of absorption occurring at 50°C, 70°C and 80°C, the existence of many models of motion from 85°C to 95°C in 8000–10000 cm?1, and so on. These results show that the molecular structure of water is very complicated, which needs further study. Furthermore, the macroscopic feature of mechanics, for instance, surface tension force of magnetized water, was also measured. Experiments discovered that the size in contact angle

关键词： pure water magnetized water magnetic-field physical property spectrum saturation and memory effect mechanical feature surface tension force polarization angles of contact

Properties of nonadiabatic quantum fluctuations of the strongly coupled electron-phonon systems

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science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 258-268页

作者： PANG XiaoFeng Institute of life science and technology,university of Electronic science and technology of china,Chengdu 610054,china International Centre for Materials Physics,Chinese academy of sciences,Shenyang 110015,china Institute of life science and technology University of Electronic Science and Technology of China Chengdu China International Centre for Materials Physics Chinese Academy of Sciences Shenyang China

A new variational-ansatz of states of electrons and phonons was proposed on the basis of the Holstein model in strongly coupled electron-phonon systems for studying the influence of nonadiabatic phonon fluctuation,arising from the motion and density fluctuation of electrons,on the properties of ground state,uncertainty relation,stability of polarons,charge density wave (CDW) and phonon staggered ordering. The new ansatz represents the correlation among the displacement and squeezing states of phonons and polaron’s state of electrons as well as the squeezing-antisqueezing effect. The correlation and squeezing-antisqueezing ef-fect result in the decrease of ground state energy,enhancement of stability of the systems,increase of binding energy of the polarons,weakening of the growing speed of polaron narrowing of the electron band,increase of the charge density wave order and suppression of the increased tendency of anomalous quantum fluctuation of the phonons in such a case,when compared with the uncorrelated case in the systems. The results obtained show that the ground state determined by the new state ansatz is most stable,thus the new ansatz describing the properties of the coupled electron phonon systems is very relevant and available,especially in strongly coupled and largely squeezed cases.

关键词： squeezing-antisqueezing effect state-ansatz polaron coupled electron-phonon systems quantum fluctuation

Effect of the silicon powder content on the properties of Al_2O_3-SiC-Me composites

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science china(Technological sciences) 2009年第1期52卷 193-197页

作者： ZHANG ZhiHui1, RUAN GuoZhi1 & CHEN YunBo1,2 1 School of Material science and engineering, Shandong university of science and technology, Qingdao 266510, china 2 Institute of Material engineering, china academy of Machinery science and technology, Beijing 100083, china School of Material science and engineering Shandong University of Science and Technology Qingdao China Institute of Material engineering China Academy of Machinery Science and Technology Beijing China

By means of transient plastic phase process, the Al2O3-SiC-Me composites were produced throungh adding metal aluminium and silicon-powder to Al2O3-SiC materials. Under the condition of the same content of silicon and aluminium mixed-powder, the effect of silicon powder addition on properties of Al2O3-SiC-Me composites was studied by means of XRD and EPMA analyses in the temperature range of 300℃―1600℃. The results indicated that the content of metal phase in the sample at 1600℃ increases with increasing silicon powder content. At the same time, when the temperature is lower than 1100℃, the strength of samples gradually increases with increasing temperature. However when the temperature is higher than 1100℃, the strength of samples gradually decreases with increasing temperature, and this change is very small. The results also indicated that at the same sintering temperature, the sample with 6% silicon powder has the maximum strength.

关键词： composites strength ceramic

pH-Dependent Stability of EGX, A Multi-functional Cellulase from Mollusca, Ampullaria crossean

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 603-608页

作者： Wen-Ying LI2, Ji WANG1, Yan-Hong LI1, Ming DING1, Gen-Jun XU1,3, Lan-Ying LIU2, and Fu-Kun ZHAO1,3* 1Key Laboratory of Proteomics, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, the Chinese academy of sciences,Graduate School of the Chinese academy of sciences, Shanghai 200031, china 2College of life science, Jilin university, Changchun 130023, china College of life science, Zhejiang university of science and technology, Hangzhou 310018, china College of life science Jilin UniversityChangchun 130023 China Key Laboratory of Proteomics Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China College of life science Zhejiang University of Science and TechnologyHangzhou 310018 China

The cellulase activity and stability of EGX, a multi-functional cellulase previously purified from the mollusca Ampullaria crossean, was systematically studied under different pH. The pH induced con- formation and stability change of EGX have been investigated by using the intrinsic fluorescence, ANS fluorescence and CD spectrum. It has been found that the conformation and activity of this cellulase were strongly dependent on the pH. EGX was stable for both the enzyme activity and the conformation from pH 5.6 to pH 7.4. As shown by intrinsic and ANS fluorescence, no red shift of emission maximum occurred and a negligible intensity change was observed at pH 5.6–7.4. The activity of EGX remained about 80% in pH 5.6–7.4 and obviously decreased out of side the pH range. Urea-induced changes in EGX at pH 5.4 and pH 8.0 were measured by intrinsic fluorescence and CD spectrum. At pH 5.4, a significantly red shift of emission maximum occurred when the concentration of urea was 5 M compared to the concentration was 3 M at pH 8.0. The α-helix at pH 5.4 was 40.51% in the absence of urea and 31.04% in the presence of 4 M urea. At pH 8.0 the α-helix was 7.23% in the presence of 4 M urea. The data indicated that EGX was much susceptible to urea-induced unfolding at pH 8.0 and much stable at pH 5.4. The greater pH dependent stability of EGX may allow the enzyme to adequately catalyze the hydrolysis of cellulosic materials under natural or industrial extreme conditions.

关键词： multi-functional cellulase stability Ampullaria crossean fluorescence spectroscopy pH-dependent structural change CD spectrum

Further study of sources of the imported cobalt-blue pigment used on Jingdezhen porcelain from late 13 to early 15 centuries

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science china(Technological sciences) 2008年第3期51卷 249-259页

作者： DU Feng1 & SU BaoRu2 1 Institute of Chemistry & Molecular engineering, Qingdao university of science & technology, Qingdao 266000, china 2 College of Information science technology, Qingdao university of science & technology, Qingdao 266000, china Institute of Chemistry & Molecular engineering Qingdao University of Science & Technology Qingdao China College of Information science technology Qingdao University of Science & Technology Qingdao China

Based on the conclusion of modern scientific analysis: the cobalt-blue pigment applied on Jingdezhen official porcelain during Yuan Dynasty and prior to Xuande reign of Ming Dynasty (1271―1425) contains high iron and low manganese con- tents, and the cobalt during Xuande and after Xuande periods (after 1426) of Ming Dynasty contains high manganese and low iron contents, in combination with the traditional archaeological method, the related historical textual records were in- vestigated and analyzed, the imported cobalt employed on Jingdezhen official porcelain was studied comprehensively, systematically and logically. In fact, 'Su Ma Li Qing' (Samarra-blue) and 'Su Bo Ni Qing' (Sumatra-blue) are definitely different cobalt ores originated in different places, because of their very similar translitera- tions in Chinese, the confusion has appeared in ancient books for more than 400 years, which considered 'Su Ma Li Qing' and 'Su Bo Ni Qing' as the same co- balt-blue pigment. In this article the mistake was corrected, the possible producing places and the approximate eras of the two pigments imported to china and used at Jingdezhen were also suggested.

关键词： imported cobalt-blue pigments employed on official blue-and-white porcelain Yuan Dynasty early Ming Dy- nasty Mn/Fe content ratio Su Ma Li Qing (Samarra-blue) Su Bo Ni Qing (Sumatra-blue) scientific archae- ological research transliteration

Flotation Separating Rutile from Calcium and Silicon Gangue Minerals

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Rare Metals 2001年第4期20卷 205-208页

作者： Hao Ding1, HaiLin 2 1) Beijing academy of Building Materials, Beijing 100041, china 2) university of science and technology Beijing, Beijing 100083, china 北京建筑材料研究院北京 100041 北京科技大学北京 100083

Rutile separation from calcite, apatite and quartz by flotation was investigated. The results show that the rutile separation from calcium and silicon gangue minerals can be realized with alkyl-imino-bismethylene phos... 详细信息

关键词： rutile calcium and silicon gangue minerals flotation separate alkyl-imino-bismethylene phosphoric acid sodium hexametaphosphate

A simple solution route to control synthesis of Fe_3O_4 nanomaterials at low temperature and their magnetic properties

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science china Chemistry 2009年第7期52卷 916-923页

作者： LIU Yi1,2, CHEN Yun1, ZENG YuPing2 & WANG ShiLong3 1 Department of Chemistry and Chemical engineering, Zaozhuang university, Zaozhuang 277160, china 2 Shanghai Institute of Ceramics, Chinese academy of sciences, Shanghai 200050, china 3 School of life science and technology, Tongji university, Shanghai 200092, china Department of Chemistry and Chemical engineering Zaozhuang University Zaozhuang China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai China School of life science and technology Tongji University Shanghai China

A series of nanostructured iron compounds including cubic Fe3O4 and orthorhombic FeOOH were synthesized via a facile low temperature (in the range of 60-100℃) solution method. In the whole process, the interaction between FeCl2·4H2O and methenamine (C6H12N4) was carried out through a reflux device under different reaction conditions such as temperature, solvent, and duration. The samples were detected by XRD, TEM, SAED, physical property measurement system, and Mssbauer spectroscopy, separately. The experiments showed that magnetic mixture nanoparticles had flake and rod morphologies, and cubic Fe3O4 took on grain nanostructure. Magnetism measurements indicated that the saturated magnetization of the as-obtained magnetic mixture was lower than that of the cubic magnetite. Mssbauer spectroscopy testified the sample consisting of cubic magnetite rather than γ-Fe2O3. In addition, a possible growth mechanism of cubic magnetic nanoparticles under different conditions was discussed.

关键词： magnetic nanoparticles cubic Fe3O4 oxidation-coprecipitation method reflux magnetic properties at room temperature Mssbauer spectrum

Anisotropic propagation of flare-induced shocks

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Chinese science Bulletin 1998年第5期43卷 402-404页

作者： HU Youqiu university of science and technology of china, Chinese academy of sciences, Hefei 230026, china Chinese academy of sciences University of Science and Technology of China Hefei China

It is demonstrated that the fastest propagation direction of a flare-induced shock deviates eastwards by about 4° at 1 AU relative to the flare normal if the shock introduced at 0.1 AU propagates along the local magnetic field, whereas it deviates westwards by about 1° if the introduced shock propagates in the radial direction instead.

关键词： solar flare MHD shock interplanetary dynamics.

Cleaning of Chromate Manufacture Process

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 132-134页

作者： Xing Zou Yi Zhang(Applied science School, university of science and technology Beijing, Beijing 100083, china)(Institute of engineering Chemistry and Metallurgy, Chinese academy of sciences, Beijing 100080, china) Applied science School University of Science and Technology Beijing Beijing 100083 China Institute of engineering Chemistry and Metallurgy Chinese Academy of Sciences Beijing 100080 China

Sodium chromate solubility is determined in the range of NaOH concentrations from 450 to 810 g/L andsolution temperatUres from 30 to 110℃. The optimized conditions to separate sodium chromate from NaOH inleached solution are resolved. It is first found the method to efficiently separate sbdium chromate from NaOH andsodium altuninate in crude sodium chromate. Bench-scale studies on the separating are performed. Finally, goodseparation results are achieved.

关键词： chromate separation clean process