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CHIRAL CONJUGATED OLIGOMER BASED ON 1,1’-BINOL WITH 3,3’-ACETYLENE-PHENYLENE-ACETYLENE SPACER

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chinese Journal of Polymer Science 2001年第5期19卷 521-526页

作者： Tian-jun Liu Ke-shen Zhang Yong-jun Chen Dong Wang Chao-jun Li Center for Molecular Science, institute of chemistry {2. academy of sciences, beijing 100080 China department of chemistry Tulane University New Orleans, LA 70118 U.S.A. chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China Tulane Univ Dept Chem New Orleans LA 70118 USA

The 1,2.-binaphthol based oligomers 3 and 7 with 3,3'-acetylene-phenylene-acetylene spacer were prepared from BINOL 1. The high optical rotation value and CD spectra demonstrated the main chain chirality of the oligomer molecule. The UV-VIS and fluorescent spectra evidence the characteristics of conjugated structure. In comparison with oligomer 2.bearing 3,3'-acetylene spacer, the oligomers 3 and 7 have longer efficient conjugation segment, and their fluorescent quantum yields (phi) increased (0.60-0.65 versus 0.14). Extending the effective conjugation segment would improve the photophysical properties of chiral conjugated polymers.

关键词： chiral conjugated oligomer BINOL 3,3 '-acetylene-phenylene-acetylene spacer

Flow microcalorimetry of adsorption of anionic alkyl surfactants at the solid/liquid interface

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chinese Journal of chemistry 1992年第3期10卷 200-205页

作者： TAN, Xin-Yi YAN, Hai-Ke HU, Ri-Heng HEPLER, Loren G. institute of chemistry, {2. academy of sciences, beijing 100080 Honorary Professor of institute of chemistry, {2. academy of sciences, present address: department of chemistry, University of Alberta, Edmonton, Alberta T6G 2.2. Canada. 1institute of chemistry Chinese Academy of Sciences Beijing 1000802Honorary Professor of Institute of Chemistry Chinese Academy of Sciences

Flow microcalorimetry was used to study the adsoption of anionic alkyl surfactants from aque-- ous solutions onto silica. It is found that for alkyl sulfate systems the strength of adsorption interaction increases with increases of the alkyl chain length and decreases as temperature rises. The adsorption depends only on monomer concentration of the solution even above the critical micelle concentration (cmc). The assumption is made that the adsorption involves only a transfer of monomers from bulk to surface phase. A different adsorption mechanism is operative for the alkyl carboxylate.

关键词： SDES

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science China Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, lu Huayu1,2. JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, institute of Earth Environment, {2. {2. of sciences, Xi’an 710075, China 2. department of Urban and Resources sciences, Nanjing University, Nanjing 2.0093, China 3. department of Earth sciences, Nanjing University, Nanjing 2.0093, China 4. department of Geography, Shaanxi Normal University, Xi’an 710062. China 5. institute of Geology and Geophysics, {2. {2. of sciences, beijing 10002., China 6 department of Geography, Qinghai Normal University, Xining 810008, China 7. Graduate School of the {2. {2. of sciences, beijing 100039, China 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the chinese academy of {2. Beijing 100039 China 2. department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. department of Earth sciences Nanjing University Nanjing 210093 China 4. department of Geography Shaanxi Normal University Xi’an 710062 China 5. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 2. visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the chineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

Stereoselective synthesis of D-α-glucopyranosides,di-and tri-saccharides via 6-O-acetyl-glucopyranosyl bromides

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chinese Journal of chemistry 1995年第5期13卷 454-459页

作者： FEI, Chang-Pei MA, Yueinstitute of chemistry, {2. academy of Science, beijing 100080, ChinaCHAN, Tak-Hangdepartment of chemistry, McGill University, Montreal, PQ, Canada department of chemistry McGill University Montreal PQ Canada

Acetyl bromide cleaved 2.3,4-tri-O-benzyl-l,6-anhydro-B-D-glucopyranose (la) or 2.3,4-tri-O-benzyl-1,6-anhydro-B-Z)-galactopyranose (1a') to give the corresponding a-D-pyranosyl bromides (2.. Reaction of 2.with ROH/diisopropylethylamine gave the corresponding a-glucopyra-nosides, di- and tri-saccharides with good yield. It was available to use 13C NMR to monitor the glycosidation reaction.

关键词： Stereoselection,α-D-pyranosyl bromide glycosidation 13C NMR

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science China Earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2. cai Qiangguo1, YUE Zhongqi3, lu Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, {2. of Geographic sciences and Natural Resources Re-search, {2. academy of sciences, beijing 100101, China 2. {2. of Forestry, {2. academy of Forestry sciences, beijing 100091, China 3. department of Civil Engineering, University of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, {2. academy of sciences, beijing 100085, China 5. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716, China Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

Heat capacity and thermodynamical properties of the crystal of [RE_2.Glu)_2.H_2.)_8](ClO_4)_4·H_2. (RE = Nd, Eu, Dy)

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Science China chemistry 2009年第7期52卷 862-867页

作者： WU XinMin1, LI Wei1, TAN ZhiCheng2.& QU SongSheng3 1 department of Chemical Engineering, beijing {2. of Petro-chemical Technology, beijing 102.17, China 2.Thermochemistry Laboratory, Dalian {2. of Chemical Physics, chinese academy of sciences, Dalian 11602., China 3 College of chemistry and Molecular Science, Wuhan University, Wuhan 430072. China department of Chemical Engineering Beijing Institute of Petro-chemical Technology Beijing 102617 China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China College of chemistry and Molecular Science Wuhan University Wuhan 430072 China

Thermodynamical data of rare earth complexes with amino acid are important for engineering chemistry and fundamental chemistry. However, they have rarely been reported. In this work, a series of crystalline complexes of rare earth perchlorate coordinated with g{2.tamic acid have been synthesized in water medium, and their thermodynamical data, inc{2.ding the heat capacity in low temperature range and the standard enthalpy of formation, were determined. These complexes were identified to be [RE2.G{2.)2.H2.)8](ClO4)4·H2. (RE = Nd, Eu, Dy) by using thermogravimetric analysis (TG), differential thermal analysis (DTA), and chemical and elementary analyses. Their purity has been determined. No melting points were observed for all the three complexes. The heat capacity of the complexes was measured by an adiabatic calorimeter from 79 to 370 K. Abnormal heat capacity va{2.es were detected for two of the complexes and the decomposition range of one complex was found. The temperature, enthalpy change and entropy change of the decomposition processes of the three complexes were calculated. The polynomial equations of heat capacity in the experimental temperature range have been obtained by least squares fitting. The standard enthalpy of formation was determined by an isoperibol reaction calorimeter at 2.8.15 K.

关键词： complex of rare earth, [RE2.Glu)2.H2.)8](ClO4)4·H2. (RE = Nd, Eu, Dy Glu = glutamic acid), low-temperature heat capacity, standard enthalpy of formation

PHOTO-CIDNP STUDIES OF PHTHALIMIDE DERIVATIVES IN THE PRESENCE OF TRIETHYLAMINE

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chinese Chemical Letters 1993年第4期4卷 331-334页

作者： Ling Jiang CHENG~(1,2. Han Cheng YUAN~3 Hua Pin PU~4 Bao Zhen YAN~3 Er Cheng LI~2.Jian Hua XU~4 Jin Shi MA~1 Guang Zhi XU~2.1 institute of Photographic chemistry,{2. academy Of sciences,beijing 100101 2.institute of chemistry,{2. academy of sciences,beijing {12. 3 department of Applied chemistry,beijing institute of Chemical Technology,beijing 10002. 4 department of chemistry,Nanjing University,Nanjing,Jiangsu 2.0008

The photoreactivity of some phthalimides was tested by CIDNP studies on the reactions with triethylamine.

关键词： CIDNP PHOTO-CIDNP STUDIES OF PHTHALIMIDE DERIVATIVES IN THE PRESENCE OF TRIETHYLAMINE

DOUBLE　SUBSTITUTE　CALIBRATION　FOR　THE　ISOTOPIC　RATIO　MEASUREMENT　AMONG　RARE　EARTH　ELEMENTS

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chinese Chemical Letters 1996年第5期7卷 499-502页

作者： Teing Lien CHANG (department of chemistry, Peking University, {2. 100871)Dun Min ZHAO (institute of Geology, academy of Geological sciences. {2. 100037) department of chemistry Peking University Beijing 100871 institute of Geology Academy of Geological Sciences Beijing 100037

Abstract: Through the application of the method of double substitute calibration using the true isotopic ratios of cerium and europium of our laboratory standards, the atomic weight of ytterbium has been determined a... 详细信息

关键词： RATIO CALIBRATION DOUBLE EARTH ELEMENTS FOR ISOTOPIC MEASUREMENT RARE AMONG

COALESCENCE INDUCED GRADIENT MORPHOLOGY NEAR A WALL IN PHASE SEPARATED POLYMER BLENDS DURING QUIESCENT ANNEALING

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chinese Journal of Polymer Science 2002年第6期20卷 543-550页

作者： Wei Yu Chi-xing Zhou De-lu Zhao department of Polymer Science and Engineering, Shanghai Jiao Tong University, Shanghai 2.02.0 China State Key Laboratory of Polymer Physics and {2., {2. of {2., chinese academy of sciences beijing 100080, China Shanghai Jiao Tong Univ Dept Polymer Sci & Engn Shanghai 200240 Peoples R China chinese Acad Sci Inst Chem State Key Lab Polymer Phys & Chem Beijing 100080 Peoples R China

A fast coalescence mechanism is proposed to account for the wall effect on the formation of gradient morphology in phase separated polymer blends during quiescent annealing. The existence of solid wall with high polarity is believed to change the potential field around the dispersed particles near the wall. This additional potential interaction between the solid wall and the dispersed particles causes faster coalescence of the dispersed particles near the wall than in the bulk. The gradient phase morphology thus formed can be predicted by combining the wall-particle interaction and the touch-coalescence mechanism. The effect of interfacial tension on the gradient morphology is also discussed.

关键词： gradient morphology wall effect coalescence polymer blends interfacial tension