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    24 July 1997, Volume 18 Issue 7
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    Articles
    Synthesis and Structure Characterization of Molybdenum Complexes with an Electronic Model Compound of Fullerene──Methyl Acrylate (η2-CH2 =CHCOOMe)2,Mo (CO)2, (bipy)
    JIN Xiang-Lin, TANG Ka-Luo, ZENG Hui, ZHENG Shi-Jun, TANG You-Qi
    1997, 18(7):  995-999. 
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    The title complexes were synthesized by the reaction of Mo (CO)4 (bipy) withmethyl acrylate, an electron-deficient alkene model compound of fullerene- Two crystals 1and 2 of a pair of geometrical isomers were obtained under different crystalization conditionsand characterized by XRDand IR.Crystal 1 belongs to the monoclinic system with spacegroup P21/n, a=0' 7800(2) nm, b= 1.9015(4) nm, c= 1.3996(2) nm, β= 1O3. 20(3)°,V=2.0210(8) nm3, Dc= 1.579 g/cm3, Z= 4.The final Ris 0.0235 for 3021 reflections[F>4.0 σ(F)].Crystal 2 belongs to the monoclinic system with space group P21/n, α =0.9075(2) nm, b=1.9491(4) nm, c=1.1291 (2) nm, β=100.52(3)°, V=1.9636(7)nm°, Dc= 1.686 g/cm3 , Z=4.The final Ris 0.0818 for 1473 reflections [F>4.0σ(F)].In the molecules of both crystals, molybdenum atom coordination is distorted octahedral.with the two COgroups cis to each orther, but each trans to a pyridyl group of 2,2' -bipyri-dine.The Mo atom is bound in an η2-fashion to C-Cdouble bonds of two methyl acrylatesin axial direction of the octahedron.The main difference in the two geometrical isomers isthat the methyl ester groups of the two methyl acrylate are rotated 180°
    Simulated Calculation of Aluminophosphate Molecular Sieves Structure and Stability (Ⅱ) ──Bond Lengths, Bond Angles and Distribution of Framework Structure
    LI Bao-Zong, XU Wen-Guo, QIU Shi-Lun, PANG Wen-Qin, XU Ru-Ren
    1997, 18(7):  1000-1006. 
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    The lattice energy of a series of aluminophosphate molecalar sieves was deter-mined by using the lattice energy minimization method.The results were compared to thelattice energy of dense polymorphs of AlPO4. All AlPO4 molecular sieves frameworks are on-ly 48-127 kJ/mol less stable than berlinite.This may explain the structural diversity andsimilarity observed for aluminophosphate molecular sieves.These XRDdata of the AlPO4molecular sieves contain a very short Al-Obond length(0.1478 nm) and P-Obond length(0.1348 nm), very long Al-Obond length (0.1942 nm)and P-Obond length (0.1678nm), and a large range of O-Al-Oangles(98.62°-122.27°) and O-P-Oangles (92.36°-122.86°), an averge Al-O-Pangle is closes to 153° and a larger range of Al-O-Pan-gles (114.80°-180°).AM1 molecular Orbital calculation have shown that there is a smallbarrier (22.97 kJ/mol) to variation in the Al-O-Pangle between 114°and 180°, and thereis the lowest energy for angles 137.74°.
    The Heterometallic Cluster Catalyzing Coordinative Hydrogenation and Isomerization Promoted by Oxygen Transfer Reagent
    LI Qing-Shan, DING Er-Run, LIU Sheng-Ming, YIN Yuan-Qi
    1997, 18(7):  1007-1011. 
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    The oxygen transfer reagent (OTR), Me3NO.2H2Oand PhIO, can promote thecoordinative hydrogenation and isomerization of 1-hexane catalyzed by heterometallic car-bonyl clusters, SRuCO2 (CO)9 and SeRuCo2 (CO)9.The tetrahedral skeleton of the catalystkeeps intact in catalysis process.In methanol solution, [1-Hexene]/[Cat.] = 200,[Me3NO.2H2O]/[Cat.] = 4, PH2 = 5.06.0 MPa, 60℃ and in 24 h are the best condi-tions.Aplausible mechanism is given.
    Studies on Simulation Chemistry of Cu-Zn Superoxide Dismutase
    LUO Qin-Hui
    1997, 18(7):  1012-1018. 
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    This paper describes comprehensively the significance and current situation ofsimulation chemistry for Cu-Zn superoxide dismutase (SOD) and the author'Sachievementsin this area.Are discussed the simulation for the active center of SOD, the behavior of theimidazolate bridge by the model complexes, the relationship between structures and func-tions of copper(Ⅱ) center, the kinetics for disproportionating superoxide ion by the SODmodel compounds and biological functions.Based on the comparison of structures and func-tions between SODand its model compounds, the structural features of the excellent SODmodel compounds are also presented.
    Synthesis and Structure of the Three Dimensional Hetero-metallic Cyano Complex with Mixed-bridge
    ZHANG Si-Wei, DUAN Chun-Ying, FU De-Gang, TANG Wen-Xia, HU Chun-Hua, CHEN Jian, ZHENG Pei-Ju
    1997, 18(7):  1019-1021. 
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    The molecular-based magnetic complex {[Cu (1, 3-Pn)]2 [Fe (CN)6] (OH).3H2O }n, where 1, 3-Pn is 1, 3-diaminopropane, has been prepared and characterized by X-raycrystallography.It crystallizes in the monoclinic system, space group P21/n, with a =0.7577(3) nm, b=1.0698(1) nm, c=1.3000(2) nm, β=90.05°, V=1.0538(5) nm3,and Z =4.The result of the crystallography indicates that this complex has a three-dimen-sional structure.
    Development of Sampling Techniques for Trace Organic Pollutants in Water──Analysis of PAHs in Water by PUF
    WANG Yi-Ru, WANG Xiao-Ru, Frank SC. Lee
    1997, 18(7):  1022-1026. 
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    The article reports the application of PUF (polyurethane foam) for PAHs sam-pling in water.The technique is found to be suitable for the sampling of PAHs and othertrace organics in different water samples.The DL(detection limit) for pyrene-d10 in 1 Lwa-ter is 26 ng/Lwhen GC/MSis used for analysis.Much lower MDLs can be achieved whenHPLC-Fluorescence is used for PAHanalysis- The observed MDLs for benzo (k)fluoran-thene, benzo (a) pyrene, dibenz (a, h) anthracene and benzo(ghi) perylene in 1 Lwater are0.86, 0.56, 2.1, 3.0 ng/Lrespectively.HPLC-Fluorescence analysis also gives very litterbackground interference by PUF.PUFsampling coupled with HPLC-fluorescence analysis isthere fore promising method for the measurement of ultratrace levels of PAHs in aquatic envi-ronment.
    Voltammetric Behavior Studies on the Interaction Between Lanthanide Ions and NAD+, NAD-LDH Complex
    WANG Xun-Qing, GAO Xiao-Xia
    1997, 18(7):  1027-1030. 
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    Voltammetric behavior studies on the interaction of Ln3+ ions with NAD+ andNAD-LDHcomplex were presented.The results showed that Ln3+ interacted with NAD+ bydividing the reduction wave of NAD+ at -0.94 Vinto two waves, which could be attributedto the binding of Ln3+ ions with the pyrophosphorous moiety of NAD+.The effect of Ln3+ions on NAD+ was progressively eliminated by adding EDTA.On mercury electrode NAD+formed a complex with LDHand was reduced at-1.16 V.The dissociation constant ofNAD-LDHwas determined.When NAD-LDHcomplex was formed, the addition of5μmol/L La3+, Ce3+, Pr3+, Eu3+, Gd3+, Dy3+, Yb3+, Lu3+ respectively increased the dis-sociation constant of NAD-LDHcomplex in the range of 40%-70%.These results could beused as an explanation for the inhibition of Ln3+ ions on LDHactivity.
    A Simple Thermospray System Used in Microwave Plasma Torch Atomic Emission Spectrometry
    LIANG Feng, ZHAO Li-Wei, ZHANG Han-Qi, JIN Qin-Han
    1997, 18(7):  1031-1034. 
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    An improved thermospray system combined with Microwave plasma torch atomicemission spectrometry (MPT-AES) was proposed.The high pressure pump was replacedwith a peristalic pump, and the appendix heating tube was removed, this improvementmakes the thermospray system more compact and economical.The effects of operation pa-rameters on the emission intensity were studied.Compared with pneumatic nebulization, thedetection limits for Mg and Pb of this system were improved to 5～10 times.And an ele-ment-selected enhancement phenomena was found.
    Studies on the Reaction Mechanism and Properties of a New Peroxidase Fluorogenic Substrate Dihydro-2 (1H) -quinoxalone
    GAO Jun, LI Yuan-Zong, HUANG Lan, WU Xin-Yuan, CI Yun-Xiang
    1997, 18(7):  1035-1040. 
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    Anew fluorogenic substrate, 3, 4-dihydro-2 (1H)-quinoxaloe (DHQXL), for per-oxidase was synthesized- It can be converted to strong fluorescent compound 2(1H)-quinox-alone(QXL) in the presence of horseradish peroxidase (HRP) or its mimetic enzymes heminand Mn-TPPS4. Pure fluorescent product was isolated by HPLC.The structure of the prod-uct was determined using1H NMRand MSspectroscopic techniques, which confirmed theproposed reaction mechanism for the enzyme catalyzed reaction.The property of the sub-strate was evaluated- The experimental results showed that it is a fluorogenic substrate forperoxidase that has a high potential in future application.
    A Fiber-optic Biosensor Based on Visible Absorption for the Dtermination of Lactate Dehydrogenase Activity
    WANG Ke-Min, LIN Zhao-Hui, CAI Wei, Chan W. H. , Lee Albert W. M.
    1997, 18(7):  1041-1045. 
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    Lactate dehydrogenase activities can be determined by using a fiber-optic biosen-sor based on visible absorption.In this method two dehydrogenate procedures were catalyzedby lactate dehydrogenase and diaphorase respectively, and coenzyme I (NAD+/NADH) wasintroduced into the two enzyme reactions as an electron transfer.The first dehydrogenateprocedure is for the recognition of lactate dehydrogense and the second one will show achange of absorbance- The sensing element of the biosonsor consists of draphorase covalencebound on the tip of the fiber bundle.Alinear response of the biosensor was obtained in therange of 0-400 U/Lof lactate dehydrogenase with a detection limit of 48 U/L- This biosen-sor has been used to determine lactate dehydrogenase activities in human serum.
    Analysis of Single Cells by Microcolumn Separation
    CHENG Jie-Ke, WANG Zong-Li
    1997, 18(7):  1046-1053. 
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    The application of microcolumn separation developed in 1990s to analytical chem-istry at the single cell level is reviewed.The new developments of single cell samplingmethodology, capillary electrophoresis and microcolumn liquid chromatographic separationand detection methods (electrochemistry, laser-induced fluorescence, immunology and ra-diometry) and their application to analysis of single cells are described in detail.
    Synthetic Studies on-2-Substituted-1,7-dioxaspiro[4.4]nonan-8-one
    WANG En-Si, SHEN Jia-Cong, Henry N. C. WONG
    1997, 18(7):  1054-1056. 
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    Employing base-promote intromolecular Michael addition as a pivotal step, 3-(3-hydroxybutyl)-2-buten-4-olide (1, 3 and 5) have been converted to disubstitued-1, 7-dioxas-piro[4.4]nonan-8-one(2, 4 and 6) under different conditions.
    Studies on the Chemical Compositions of the Marine Sponge Rhaphisia pallida(I)──The Structural Elucidation of Two Novel Ten-membered Heterocyclic Compounds
    CEN Ying-Zhou, SU Jing-Yu, ZENG Long-Mei
    1997, 18(7):  1057-1060. 
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    From the marine sponge Rhaphisia pallida Ridley, collected from the South Chinasea, two pure compounds have been obtained.Avariety of spectroscopic techniques such asUV, IR, EIMS, FABMS, 1D NMR, 1H-1H COSY, 1H-13C COSY NMR, have been appliedin the structural elucidation of these two compounds.Compounds ⅠandⅡare very inter-esting in having a ten-membered heterocyclic ring, combining a urea unit and a diacylimidemoiety.This is the first report of such novel structure-
    Syntheses and Structure-activity Relationship of Podophyllotoxin Derivatives as Potential Anticancer Drugs
    WANG Yan-Guang, TAO Lan, PAN Jian-Lin, SHI Jian-Feng, CHEN Yao-Zu
    1997, 18(7):  1061-1066. 
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    Thirteen new 4β-substituted podophyllotoxin derivatives 5-17 were synthesizedand their structures were confirmed by IR, MS, 1H NMRand ESRas well as elementaryanalysis.All new compounds were evaluated for their anticancer activity against mouseleukemia P388 and human stomach carcinoma SGC-7901 cells in vitro- Compounds 5, 7-10exhibited a remarkable inhibition activity against both P388 and SGC-7901 cells.In a struc-ture-activity comparison it was found that 4' -O-demethylpodophyllotoxins 5, 10-13 showeda superior activity to the corresponding 4' -methoxy analogues 6, 14-17 lacking a free OHgroup at C-4'.The replacement of the "-NH-" bridge at C-4 with the "-O-" bridge re-sulted in lowering of the anticancer activity.These results demonstrate the possibility ofconsiderable simplification in the sugar structure of VP-16 and the importance of 4' -phenolichydroxyl group, and suggest further elaboration of 4β-nitrogen-containing substitutlent tooptimize the structure of this class of anticancer compounds.
    Halocarbonyl Ylide: the Effect of “Push-Pull”Stabilization on Deoxygenation of Tetraphenylcyclopentadienone in Carbene Reaction
    CHENG Jin-Pei, WANG Hong-Xing, HYAN Zhen-Wei, TAN Chang-E, Landgrebe John. A.
    1997, 18(7):  1067-1071. 
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    An unexpectedly high yield of carbon monooxide as a deoxygenationproduct of carbonyl compound was obtained in the reaction of tetraphenyl-cyclopentadienone with dibromocarbene using phenyl tribromomethyl mercury asthe carbene precursor.This unique phenomenon is rationalized in terms of thepush-pull stabilization gained from the interaction between the partially aromaticcyclopentadienide moiety and the positively charged dibromomethylene moiety inthe dihalocarbonyl Ylide-like transition state.
    Studies on D-Galactose-containing DTPA Bisamide Gadolinium Complexes as Liver-targeting MRI Contrast Agents
    FU Yan-Jun, ZHUO Ren-Xi
    1997, 18(7):  1072-1079. 
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    New lactose-or D-galactose-containing diethylenetriaminepentaacetic acidbisamide ligands and their gadolinium complexes were synthesized by the reaction of bis(N-hydroxysuccinimide ester)of diethylenetriaminepentaacetic acid with amino-containing lac-tose or D-galactose derivatives.Chemical structures of ligands and Gd complexes were char-acterized.In vitro spin-lattice relaxivity and acute toxicity in mice of the complexes havebeen preliminarily investigated.Magnetic Resonance lmaging for rabbit shows that the con-trast agent bearing galactose could be targeted to the liver.
    Homolytic and Heterolytic C-H Bond Dissociation Energies of a-V (or Ⅵ)-Group Cation-substituted Toluenes and Acetophenones
    CHENG Jin-Pei, LIU Bo, LU Yun, MI Jiang-Lin, HUAN Zhen-Wei
    1997, 18(7):  1081-1085. 
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    Eleven α-V (or Ⅵ)-group cation-substituted toluenes (1) and acetophenones (2)were synthesized.The equilibrium acidities (PKa) of these compounds were determined indimethyl sulfoxide solution by the "Overlapping Indicator Method" and the homolytic C-Hbond dissociation energies (BDE) were derived from a thermodynamic cycle combining PKawith oxidation potential of carbanion.The effects of the a-positively charged groups on thethermodynamic stabilities of sixteen Ylide carbanions and the corresponding Ylide-like radi-cals and the remote structral effect have been discussed.
    Application of Four Novel Organophosphorus Compounds as Coupling Reagents for Synthesis of Bioactive Peptides
    YE Yun-Hua, FAN Chong-Xu, ZHANG De-Yi, XIE Hai-Bo, HAO Xiao-Lin, TIAN Gui-Ling
    1997, 18(7):  1086-1092. 
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    Four novel organophosphorus compounds: N-diethylphosphoryl benzoxazolone(DEPBO), N- (2-oxo-1, 3, 2-dioxaphosphorinanyl)-benzoxazolone (DOPBO), 3- [O- (2-oxo-1, 3, 2-dioxaphosphorinanyl)-oxy]-1, 2, 3-benzotriazin-4 (3H)-one (DOPBT) and 3-(di-ethylphosphoryl-oxo) -1, 2, 3-benzotriazine-4 (3H)-one (DEPBT) have been studied for pep-tide synthesis.All of the four compounds are stable colourless crystal which can be easilyprepared in large quantity.We have synthesized a number of bioactive peptides such as ana-logues of delta sleep inducing peptide, a cyclic heptapeptlde isolated form Caryophyllaceae,etc.by using these organophosphorus compounds as coupling reagents in both solution andsolid phase peptide synthesis.In the coupling reaction, the hydroxy group in amino compo-nent does not need to be protected and the dehydration of asparagine which is easily causedby DCCor EDCwas not observed.We have also compared our organophosphorus com-pounds with other coupling reagents such as DCC/HOBt, BOP, etc.In terms of reactionyield, our compounds are as good as other commonly used coupling reagents.Among thefour compounds, DEPBTgives the best results.As far as the racemization is concerned, es-pecially in the hindered coupling or in the cyclization, DEPBTis much better than the oth-ers.
    Studies on 1H and 13C NMR Spectra of Ditertiary Phosphine Bis-substituted Derivatives of Butterfly Fe/SeCluster Complex (μ-p-MeC6H4Se)2Fe2 (CO)6
    SONG Li-Cheng, YAN Chao-Guo, MAO Xi-An
    1997, 18(7):  1093-1097. 
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    The NMRsignals in1H-1H COSY, 1H and 13C COSYand 1H-1H NOESYspectra ofditertiary phosphine bis-substituted derivative (μ-p-MeC6H4Se),Fe,(CO)4.(Ph2PCH2CH2PPh2) and those 1H-1H COSYand 1H-13C COSYspectra of ditertiary phos-phine bis-substituted derivative (μ-p-MeC6H4Se),Fe2 (CO)4 (Ph2CH = CHPPh2) have beencompletely assigned and thus their structures have been further confirmed.
    Studies on Synthesis and Antitumor Activities of Analogues and Segments of Papaver Somniferum Pollen Heptadecapeptide
    XU Jia-Xi, JIN Sheng
    1997, 18(7):  1098-1102. 
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    Four analogues and three segments were designed and synthesized by using solidphase peptide synthesis method according to separated papaver somniferum pollen heptade-capeptide with promoting immunity and antitumor activities as the leading compound.Theirprimary secondary structures in solution were determined by CDspectra and their inhibitiveactivities to human gastric and bladder cancer cells were assayed by MTTmethod.The rela-tionship of structure-activity was preliminarily discussed.
    Synthesis and Enzymatic Stability of oligonucleotide Incorporated with Isonucleoside
    YU Hong-Wu, ZHANG Liang-Ren, MA Ling-Tai, ZHANG Li-He
    1997, 18(7):  1103-1106. 
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    Two trideoxynucleotides incorporated with 3'-(S)- (thymin-1-yl)-4'-(R) -hydroxy-5' -(S)-hydroxymethyl tetrahydrofuran in the 3' end (3) or in center (4) were synthesized via phos-photriester method in solution.Compounds 3 and 4 are stable towards Nuclease S1 compared withthe normal trideoxynucleotides (2).
    Recent Studies on Diterpene Esters and Their Bioactivities from Euphorbia Genus in China
    SHI Yan-Ping, JIA Zhong-Jian
    1997, 18(7):  1107-1112. 
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    The genus Euphorbia (Euphorbiaceae) consists of about 2000 species distributedthroughout the world.Over 80 species of them grow in China used as antitumor agents inChinese folk medicine.Agreat number of phytochemical and pharmacological investigationsshowed that the bioactive constituents existing in the genus are diterpenoids, which exhibittoxic, irritant, cocarcinogrnic activities as well as anticancer and antileukemic activities.More than 300 diterpenoids owning fourteen carbon skeleton types (Fig.1) have been lsolatedand characterized from the genus still now.In this paper, new diterpene esters from EuPhor-bia genus in China(Fig.2-6) and their irritating, anticancer and bactericide activities in thelatest years (from 1986 to 1996), were reviewed, including twenty polyfunctional diterpeneesters with five novel carbon skeleton types (Euphoractine A, Euphoractine B, EuphactineA, Spr-ol and Euphoreppinol, cf.Fig- 1 and Fig.7).
    Recent Advances in the Stereoselective Synthesis of Glycosides and Oligosaccharides
    LI Zhong-Jun, CAI Meng-Shen
    1997, 18(7):  1113-1119. 
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    Glycoprotein, glycolipids and glycophospholipids are encountered in cell mem-brances.The biological information in these substances is carried mainly by the carbohydratepart.Much attention has been focused on the stereoselective synthesis of glycosides andoligosaccharides.In this paper, recent advance in their stereoselective synthesis is reviewed.
    Reaction Energetics for Methanol Synthesis from CO2/H2 over the Clean and the Oxygen-Modified Cu(100) Surfaces
    WANG Hai-You, XIA Wen-Sheng, WAN Hui-Lin, QU Zeng-Shang
    1997, 18(7):  1120-1124. 
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    Clean and oxygen-modified Cu(100) surfaces have been used to model the metallicand the partially oxidized copper surfaces respectively.Activati0n energies for elementary re-actions involved in the methanol synthesis from CO2/H2 over Cu (100) and Cu (1O0)-p(2×2)Osurfaces have been calculated using bond order conservation-Morse potential approach.The following conclusions have been obtained: the main pathway for methanol formation canbe expressed as "CO2,s→HCOO3→H2CO3→CH3O3→CH3OHs"; In comparison withthat over the clean Cu(100) surface, each elementary reaction involved in methanol synthesishas a lower activation energy over the oxygen-modified Cu(100) surface;HCOOs is the com-mon precursor intermediate for methanol and COformations and the selectivity of methanolis governed by the relative reaction rate of hydrogenolysis of formate to the dissociation offormate (to COs+ OHs); Over the clean Cu(100) surface, the activation energy for formatehydrogenolysis is similar to that for formate dissociation to COs and OHs, while the former ismuch lower than the latter over the oxygen-modified Cu (100) surface- Judging by the activa-tion energies, we conclude that methanol synthesis from CO2/H2 is more favorable over thepartially oxidized copper surface than that over the metallic copper surface.
    Theoretical Studies on the Structures and Electronic Spectra and NMR Spectra of Various Possible Isomers of C60O2
    TIAN Wei-Quan, FENG Ji-Kang GE Mao-Fa, REN Ai-Min, LI Zhi-Ru, SUN Chia-Chung
    1997, 18(7):  1125-1130. 
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    Intermediate Neglect Differential Overlap (INDO) calculations were employed to study the six possible isomers of C60O2,the two oxygens were added to the edges 6-6 ring or the 5-6 ring to form an epoxide structure with C5 symmetry.The calculation results indicate that the structure of C60O2 in which the two oxygen atoms are added to the two double-bonds of the same six-membered ring to form epoxide is the most stable,and the C-Cbonds of epoxide are not broken.The calculated electronic spectra are in good agreement with recent experimental results.The C-Cbond in the hexagon of epoxide in C60O2(C5) has a large bond order with a high activity and maybe C60O2 has a high reactivity.
    Comparison Studies on the Catalysis Process of Methanol Synthesis from CO2+H2 and (CO/CO2) +H2
    SUN Qi, ZHANG Yu-Long, MA Yan, DENG Jing-Fa
    1997, 18(7):  1131-1135. 
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    The catalytic processes of methanol synthesis from CO2+H2, CO+H2 and (CO/CO2) +H2 have been studied.The results indicate that methanol is primarily formed fromCO2 hydrogenation for both CO2+H2 and (CO/CO2) +H2. Due to the limitation of thermaldynamics, the yield of methanol is low for CO2 hydrogenation.In the process of (CO/CO2)+H2, methanol selectivity and formation rate are promoted greatly due to the recycle processof methanol synthesis from CO2+H2 and reverse water-gas shift reaction.As a result, thelimitation of thermodynamic equilibrium of methanol synthesis from CO2, hydrogenation ismoved to the favorable side of methanol synthesis.Anovel reaction mechanism is proposed.
    A Vibrational SCF-CI Method for Determining Rovibrational Eigenstates of Weakly Bound Complexes
    XIE Dai-Qian, YAN Guo-Sen
    1997, 18(7):  1136-1140. 
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    Avibrational self-consistent field-configuration-interaction(SCF-CI)method for determining rovibrational eigenstates of weakly bound A-BCcomplexes is suggested.In theSCF-CImethod, the SCFmethod is used to optimize the basis sets for intermolecular bend-ing and stretching motions, then the CImethod is used to determine the precise rovibrationalenergy levels and the wavefunctions.The radial basis function is not an analytical form, butis determined numerically from the stretching one dimensional SCFequation by using therenormalized Numerov-Johnson algorithm.The related integrals over the radial basis func-tions can be evaluated conveniently by using the HEGquadrature.In order to test this SCF-CImethod, the calculated results of the rovibrational bound states for Ar-HCl and Ar-N2complexes are presented together with comparison of the results obtained from other theoret-ical approaches- The results show that the SCF-CImethod may provide a comparable level ofaccuracy by using fewer configurations-
    Electrochemistry Behavior and Ion-pair Effect of Ferrocene in Self-assembled Monolayers
    CHENG Guang-Jun, YU Hua-Zhong, SHAO Hui-Bo, XIA Nan, LIU Zhong-Fan
    1997, 18(7):  1141-1146. 
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    Ferrocenylalkanethiol (HSC10Fc) can be self-assembled into a stable and repro-ducible monolayer on gold.The self-assembled monolayer(SAM) showed a reversible redoxbehavior in 0.1 mol/L HClO4 solution, while its voltammetric properties was influenced byboth type and concentration of the supporting electrolytes.On the basis of "ion pair" effect,a detailed experimental investigation was performed to evaluate the role of type and concen-tration of the different anions in determining the shapes and positions of the redox peaks.Atthe same time, the mixed monolayer of HSC10 Fc with HSC11 CH3 was prepared, whichshowed varied electrochemical behavior comparing to the pure monolayer.However, the ion-pair effect was the same as the pure monolayer.
    Valence π-bonding　 Dewar Structures and Free π-Radical Structures of Metallofullerenes
    CHIU Ying-Nana, XIAO Ji-Mei, XIAO Xing-Cai, HUANG Wen-Xiu, LI Norman N.
    1997, 18(7):  1147-1152. 
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    Theoretical considerations of the valence π-bonding and free π-radicals of fullereneshave been made.These will yield various possible symmetries and structures of the endohedral aswell as exohedral single and multiple metallofullerenes.Aside from C60 (Ih), C34 (C3v) andC28(Td), we also consider C33 (C3), C56 (Td) and C68 (Td).Such valence views will provide newaspects for the opposite views of molecular orbital calculations as well as for the arrangement ofmolecular works.
    HREELS Studies of Ethanol Adsorption and Decomposition on Rh(100) Surface
    TIAN Zhi-Jian, WEI Xu-Ming, ZHAI Run-Sheng, REN Su-Zhen, LIANG Dong-Bai, LIN Li-Wu
    1997, 18(7):  1153-1158. 
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    The adsorption and decomposition of ethanol on the clean Rh (100) surface werestudied using thermal desorption spectroscopy(TDS) and high resolution electron energy lossspectroscopy (HREELS).At 130 K, on Rh (100) surface, the adsorption started from achemisorbed ethanol structure which was bonded to the surface through both Oand Hmoi-eties, with the O-Hbond almost parallel to the surfaces.Additional condensed phase of ad-sorbed ethanol was found to exist through hydrogen bonding.At about 150 K, the multilay-er-adsorbed ethanol desorbed from the surfaces, while the remaining chemisorbed ethanolcompletely converted to an ethoxy species via the first decomposition step in which O-Hbond scission occurred.The small amount of methane formed indicated that the dehydro-genation of the ethoxide intermediates on the clean Rh(100) surface was non-selective.Lossof hydrogen from the methylene group would result in the formation of an aldehyde interme-diate.Decarbonylation of the aldehyde intermediates produced methane and CO.This path-way appeared to be a minor one for ethoxide decomposition on Rh(100).The main ethoxidedehydrogenation proceeded via the cleavage of a C-Hbond on the methyl group, resultingin the formation of an oxametallocyclic intermediate.The loss spectra at 629 cm-1 is as-signed to this intermediate.The C-Cbond scission occurred at the same time in the oxamet-allocyclic dehydrogenation sequence.Then the COand hydrocarbon moieties were formed onthe surface.
    High Efficiency CO Adsorbent CuCl/Zeolite
    XIE You-Chang, ZHANG Jia-Ping, TONG Xian-Zhong, PAN Xiao-Min, FU Jin-Ping, CAI Xiao-Hai, YANG Ge, TANG You-Qi
    1997, 18(7):  1159-1165. 
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    Based on the principle that compounds can spontaneously disperse to the surfaceof supports to form a monolayer, heating supports of high surface area such as γ-Al2O3, 4A,13X, NaYand CuYzeolites etc.with CuCl adsorbents with CuCl highly dispersed on thesurface of the supports can e btained.XRDand EXAFSexperiments have shown that theCuCl is in atomic scale dispersion.The best adsorbents CuCl/NaYand CuCl/CuYcan haveCOcapacity of 90 mL/g support and 100 mL/g support respectively at 20℃ and COpartialpressure of 60 kPa.A CuCl/zeolite adsorbent PU-1 whcih has optimization recipe and suit-able binder has been made in commercial scale.The adsorbent has been used in a PSApro-cess successfully to separate COfrom gas mixtures of CO, H2,N2, CH4 and CO2. The COproduct has a purity >99% with yield>85%.It has also been used to remove trace COinH2 or N2 at >5000 h.The purified gases have CO <1 X 10-6 mol/L.
    Comparison of Several Density Functional Formulas by Application to Calculations of Lanthanide Chalcogenides
    DAI Da-Di, LI Le-Min
    1997, 18(7):  1166-1170. 
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    The applicability of several density functional formulas to theoretical calculationsof lanthanide chalcogenides has been investigated by per forming calculations on LnL(Ln=La, Gd, Lu 3 L=O, S, Se, Te).The influence of relativistic effects has been considered.The calculated results show that the relativistic effects result in variation of bond lengths from +2 pm to -3 pm, and result in bond energy decrease by 0- 4~O.6 eV, and there is noobvious dependance on the adopted density functional formulas.The difference of densityfunctional formulas does not obviously affect the calculated bond lengths, but signifacantlyinfluence the calculated bond energies.It is found that LDA (VWN) +PW86x scheme givesthe best bond energy.The gradient correction of exchange energy obviously improves thecalculated bond energies, whereas the gradient correction of correlation energy worsen theresults, in consistency with previous conclusions.The simple Xα formula gives pretty goodcalculated bond energies.Taking the relativistic effects and suitable gradient corrections intoaccount,the density functional method gives satisfactory bond lengths, while the calculatedbond energies are still too high, although the relative deviation does not exceed 20%.
    An ab inito Study on the Conformation and Gold(I)-Gold(I) Interaction of the Isomeric H2C[P (Ph)2AuX]2 and HC[P (Ph)2AuX], (X =I, Cl)
    SU Zhong-Min, ZHANG Hong-Xing, Chi-Ming Che
    1997, 18(7):  1171-1179. 
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    Ab initio calculations were carried out on the complexes H2C[P(Ph)2AuX]2 (X = I,Cl)and HC[P (Ph)2AuX]3 (X = I,Cl) according to their crystal structures.The potential energy curvesof the conformations with respect to the rotations of C-Pbonds were generated at MP2 approxi- mate levels, which reveals Au (I)-Au (I) interactions.The calculations show that theAu(I)-Au(I) interactions exist in all the four complexes with the weak attraction about 10.0-16.5 kJ/mol that is close to the estimation of Schmidbaur and the calculation of Pyykko et al.for other model complexes.
    Platonic Polyhedron and Fullerenes
    TANG Au-Chin, LI Qian-Shu
    1997, 18(7):  1180-1184. 
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    On the basis of symmetry and geometry characters of Platonic polyhedrons, thebounding properties of the molecules with platonic polyhedron symmetry are discussed, andthe geometrical relationship is discribed between Platonic polyhedrons and frameworks ofcluster molecules with high symmetry, especially between Platonic polyhedrons andfullerenes.
    Evolution and Significance of Molecular Design Conception in the Development of Stereo-selective Transition-metal Complex Catalysts
    WAN Hui-Lin, YUAN You-Zhu, GAO Jing-Xing, ZHANG Hong-Bin, ZHU Gui-Yun
    1997, 18(7):  1185-1193. 
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    The mutual promotion of the development of stereo-selective coordination cata-lysts involving transition-metal coordination compounds and the development of the concep-tion of molecular design of such catalysts was discussed, as illustrated by three typical typesof stereo-selective coordination catalysis, namely, asymmetric synthesis, stereo-selective co-ordination polymerization of α-olefins, and hydroformylation of α-olefins.With this discus-sion, it is shown that for the molecular design of certain types of stereo-selective coordina-tion catalysts, there has already been sound scientific basis for the development of computer-aided design (CAD).
    Research on the Langmuir-Blodgett Films of Rare Earth-β-diketone Complexes and Triplet Energy Transfer
    ZHONG Guo-Lun, YANG Kong-Zhang, FENG Yu, ZHU Gui-Yun
    1997, 18(7):  1194-1196. 
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    The Langmuir-Blodgett (LB) technique was used for studying enhanced lumines-cence of Eu (TTA)3 Phen (acceptor) by La (TTA)3 Phen (donor).LBfilms studied here are:(1) [0.5% Eu (TTA)3 Phen + 99.5% La (TTA)3 Phen]: AA = 1: 1; (2) [0.5%Eu(TTA)3 Phen+99.5%AA]: AA= 1: 1; (3) La(TTA)3 Phen: AA= 1: 1.These filmscould form stable monolayers at air/water surface.The fluorescence intensity of LB 1 was 65times stronger than that of LB2.This signifies that the luminescence intensity ofEu(TTA)3 Phen could be enhanced by La (TTA)3 Phen clearly.Low angle X-ray diffrac-tog ram of LB1 showed that the film has a period layered structure.To study the intermolec-ular energy transfer, different structures of the multilayer were designed by combining LB2(layer of acceptor) with LB3(layer of donor).The results indicated that the intermolecularenergy transfer occurred in a short-range (<3 nm) and at the position of head-head in Y-typemodel.The influence of the interface on the energy transfer was prominent.The process ofenergy transfer was carried out via the triplet state of TTA.
    A Pan-milling Type of Equipment and Its Application in Developing Polymer Materials
    WANG Qi, XU Xi
    1997, 18(7):  1197-1201. 
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    The characteristics of a pan-mill type of equipment, which is designed and manu-factured in our lab.for pulverizing, mixing and stress reactions of polymers and fillers, werepresented in this paper.The structural changes of polypropylene, polyethylene, poly(vinylchloride), polystyrene and titanium oxide during pan-milling were reported, and the poten-tial application of the pan-mill type equipment to developing polymer materials was dis-cussed.
    Polymerization of Methyl Methacrylate by Chitosan-supported Rare Earth Catalysts
    ZHANG Yi-Feng, ZENG Xian-Biao, SHEN Zhi-Quan
    1997, 18(7):  1202-1206. 
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    Polymerization of methyl methacrylate (MMA) by chitosan-supported rare earth(Cs.RE)-Al (i-Bu)3-ε-caprolactone (CL) catalytic system has been investigated.From ki-netics of MMApolymerization and distribution of molecular weights of polymer sample,monomer reactivity ratios and the curve of copolymer composition in copolymerization ofstyrene and MMA, the polymerization of MMAwith the Cs.Y-Al (i-Bu)3 -CLcatalyst ismost likely to take place via a coordinate anionic mechanism.The microstructure of poly(methyl methacrylate) is determined by IR, DSC, 1HNMRand 13C NMR.Syndiotacticity of PMMA (polymerization at 60℃) is as high as 86.4% and its Tg, is 123.9℃ These resultsdlsclose that chitosan-supported rare earth catalytic system has high stereospecificity.
    Syntheses of Poly(phosphate-urethane)s as Drug Release Materials
    ZHUO Ren-Xi, WANG Jun, MAO Hai-Quan
    1997, 18(7):  1207-1211. 
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    New biodegradable and biocompatible copolymers poly (phosphate-urethane) swith elevated molecular weight were synthesized by the polycondensation of Ser-Tyr orTyr-Tyr dipeptide and phosphorodichloridate and followed by reacting with 1,4-butane-di-isocyanate.The chemical structures were confirmed by 1HNMR, FTIRand elemental analy-sis.The molecular weight, and thermostability of these polymers were investigated.The invitro degradation and bovine serum albumin (BSA) release profile were also studied.It wasfound that the degradation rate of the materials and BSArelease behavior can be modulatedby varying the hydrohobic properties of these poly(phosphate-urethane)s.
    Polymeric Adsorbents for Blood Purification
    HE Bing-Lin, MA Jian-Biao
    1997, 18(7):  1212-1218. 
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    In this brief review it was summarized the recent development of polymeric adsor-bents for blood purification made in our laboratory.The researches were focused on thepolymeric adsorbents to bind small organic molecules, middle molecular substance, and bio-logical macromolecules in blood.Some adsorbents with perfect adsorption properties andgood biocompatibility have been invented and begun to apply for hemoperfusion in clinic.
    The Compositing and Assembling of Semiconductor Nanoparticles in Polymer Matrix
    YANG Bai, HUANG Jin-Man, HAO En-Cai, SHEN Jia-Cong
    1997, 18(7):  1219-1226. 
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    In this paper, some research work of ours was summarized which concerns thepreparation, compositing, assembling and properties of semiconductor nanoparticles in poly-mer matrix.Some questions such as particle size, size distribution, surface modifying, com-positing process and assembling dimension were discussed.
    Modification and Immobilization of Enzymes and Other Biological Macromolecules by Polymer Materials and Their Biomedical Applications
    MA Jian-Biao
    1997, 18(7):  1227-1235. 
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    In this review, it is summarized the recent progress in biomedical polymers withbiological functions in our laboratory, including chemical modification of L-asparaginase withnatural and synthetic polymers, synthesis of dextrin magnetic nanoparticles as carriers for,the immobilization of enzyme and antibody, polymeric latexes useful in the detection of DNA hybridization, enzyme immobilization on porous polymeric beads, immobilization of enzymesin the conducting polymer membrane and fabrication of bioelectrodes, as well as biomimeticpolymers of molecular recognition.
    Concentration Dependence of the Radius of Gyration and Translational Diffusion Coefficient of Linear Polystyrene Chains in Cyclohexane
    WANG Xiao-Hui, QIAN Ren-Yuan, WU Chi
    1997, 18(7):  1236-1239. 
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