1991 Volume 2 Issue 1

SYNTHESES AND OLFACTORY CHARACTERS OF SOME END-α-SUBSTITUTED-BICYCLO [2.2.2] OCTENYL (AND OCTANYL) METHANOLS
Shi Xiong TANG , Jia You XUE , Xiu Lin WANG , Yu Rong CAO , Xiao Lan WANG
1991, 2(1): 1-2
[Abstract](176) [FullText HTML] [PDF 78KB](2)
Abstract:
Ten endo-α-substituted-bicyclo[2.2.2]octenyl (and octanyl) methanols were synthesized, their odors were evaluated.
STEREOCHEMISTRY IN CYCLOPHOSPHORYLATION OF NUCLEOSIDES
Li Ho ZHANG , Cheng XU , Chun Guang WANG , Hai Ying CAI , Yuan Peng DAI
1991, 2(1): 3-6
[Abstract](184) [FullText HTML] [PDF 127KB](2)
Abstract:
In the presence of tetrazole, 2'-substituted nucleosidesreacted stereospecifically with n-BuOPIN (C2H5) 2I2 to nucleoside 3', 5'-cyclophosphites with avial n-Buo group. The stereochemistry of oxidation of cyclophosphite was investigated.
STUDIES ON THE SYNTHESIS OF ISOSARCOPHYTOL-A
Yu Lin LI , Wei Dong LI , Ying LI
1991, 2(1): 7-8
[Abstract](178) [FullText HTML] [PDF 360KB](2)
Abstract:
A precursor 9 of isosarcophytol-A (1) was prepared from (E, E)-farnesol (3) through 6 steps.
EFFECT OF HYDROGEN BONDING ON DIRECTION OF PHOTOISOMERIZATION OF RETINOIDS:THE ORIGIN OF THE SOLVENT POLARITY EFFECT.
Bao Wen ZHANG , Robert S. H. LIU
1991, 2(1): 9-12
[Abstract](192) [FullText HTML] [PDF 174KB](2)
Abstract:
Studies of direction of photoisomerization of retinal, retinonitrile, α-retinonitrile and a trienenitrile analog in different solvents with varying wave-lengths of excitation and reaction temperature led to the conclusion that the well known solvent dependent photochemistry of retinoids is due to selective excitation of the hydrogen bonded species.
PHYTOECDYSONES FROM THE ROOTS OF TINOSPORA CAPILLIPES
Chun Qing SONG , Ren Sheng Xu
1991, 2(1): 13-14
[Abstract](175) [FullText HTML] [PDF 105KB](2)
Abstract:
In addition to 2-deoxycrustecdysone (1), we isolated and identi-fied two new natural moulting hormones-2-deoxy-3-epicrustecdysone (2) and 2-deoxycrustecdysone-3-O-β-D-glucopyranoside (3) from the roots of Tino-spora capillipes, it is the first time to get ecdysteroids from this genus.
STRUCTURAL STUDIES OF PECTIC POLYSACCHARIDES FROM THE POLLEN OF Codonopsis Pilosula [Franch] Nannf.
Zhanzhu LIU , Sheng JIN
1991, 2(1): 15-16
[Abstract](180) [FullText HTML] [PDF 253KB](2)
Abstract:
Five pectic polysaccharides CPA-CPE were purified from the pollen of Codonopsis Pilosula [Franch] Nannf. They are all composed of L-arabinofuranosyl and D-galactopyranosyl residues. The results of methylation analysis and periodate oxidation and Smith degradation revealed that CPA was a highly branched arabinogalactan probably with a backbone of (1→6) D-Galp. Electron micrograph of CPA showed a secondary structural feature of a string of pearls.
SALVIANOLIC ACID G,A CAFFEIC ACID DIMER WITH A NOVEL TETRACYCLIC SKELETON
Chun Bo AI , Lian Niang LI
1991, 2(1): 17-18
[Abstract](169) [FullText HTML] [PDF 80KB](2)
Abstract:
Salvianolic acid G, a caffeic acid dimer with a novel tetracyclic skeleton was isolated from the roots of Salvia miltiorrhiza. Its structure was elucidated by chemical and spectral analysis, especially by 2D NMR analysis.
GC-MS STUDY ON DIURETICS IN URINE Ⅱ.DETECTION METHOD USING TRIMETHYLSILYLATION
Ya Wei LI , Jun LI , Tong Hui ZHOU
1991, 2(1): 19-22
[Abstract](183) [FullText HTML] [PDF 235KB](2)
Abstract:
A reliable method is described for the detection of amitoride, triamterene. canrenone and spironolactone in human urine using GC-MS analysis after trimethytsitytation. The mass spectrometric and metabotic features of the compounds are discussed.
REVERSE VARIABLE-ANGLE SYNCHRONOUS SPECTROFLUORIMETRY FOR RAPID SIMULTANEOUS DETERMINATION OF CHLOROPHYLL A AND CHLOROPHYLL B
Yao Qun LEE , Xian Zhi HUANG , Jin Gou XU , Guo Zhen CHEN
1991, 2(1): 23-26
[Abstract](165) [FullText HTML] [PDF 389KB](3)
Abstract:
Rapid simultaneous determination of chlorophyll a and chlorophyll b by reverse variable-angle synchronous spectrofluorimetry has been studied on a laboratory-constructed microcomputer-controlled versatile spectrofluorimeter. A method in estimation of scan parameters for the determination of two-component system by variable-angle synchronous spectrofluorimetry has been suggested.
ELECTROANALYTICAL STUDY OF XANTHOPHYLL AND ITS APPLICATION
Nai Xing WANG , Jian Min CHEN , Xiao Lan ZHANG
1991, 2(1): 27-28
[Abstract](184) [FullText HTML] [PDF 97KB](2)
Abstract:
The electroanalytical behaviour of xanthophyll was studied by differential pulse polarography and cyclic voltammetry. The reduction wave of xanthophyll at-0.92V (v. s. Ag/AgCl) in 1.25% tetrabutyl ammonium chloride solution (TBAC) was found for the first time. The optimum conditions for the determination of xanthophyll by DPP were established. The results from the application of cyclic voltammetry to study electrode process behaviour showed that the electrode reaction of xanthophyll at a hanging mercury electrode is quasi-reversible reaction.
COULOMETRIC TITRATION OF MYLIS
Li Xin XU , Ai Ru LIU
1991, 2(1): 29-30
[Abstract](220) [FullText HTML] [PDF 67KB](2)
Abstract:
A method for the determination of Mylis by coulometric titration was developed. The titration was carried out in a mixture of 1 mol/L KBr-2 mol/L HCl (1:1) and bromine was generated at the anode, Mylis reacted with one mole of bromine with a n value of 2. The advantages of this method are simple and rapid, it can be used to analyze small amount of sample.
MULTIDIMENSIONAL GAS CHROMATOGRAPHY FOR THE SEPARATION OF TCDD ISOMERS
C. R. JIA , Y. H. QIU , Q. Y. OU
1991, 2(1): 31-34
[Abstract](180) [FullText HTML] [PDF 138KB](2)
Abstract:
A multidimensional gas chromatographic technique with heartcutting was used for the determination of complex isomeric mixtures of tetra-chlorodibenzo-p-dioxins (TCDDs) which could not be completely separated on a single capillary column. When using so-called heartcutting technique, only the interested single peak or section of the fraction eluting from the first column was transferred onto the second column with different stationary phase. Flame ionization detection was used as the monitor detector and electron capture detection as the main detector. This arrangement offers complete separation and avoids interference of the possible remained chlorinated solvents. The separation power of multi-dimensional GC was demonstrated by the determination of TCDD isomers.
THE STUDIES OF THE ANALOGUES OF 9-β-D-XYLOFURANOSYL-ADENINE BY FAB-MASS SPECTROMETRY
Ji Hai PANG , Bin YANG
1991, 2(1): 35-36
[Abstract](181) [FullText HTML] [PDF 84KB](2)
Abstract:
The paper studies the chemical structures of eight synthetic 9-β-D-xylofuranosyl-adenine-8-subatituted amino derivatives, by Fast Atom Bombardment Mass Spectrometry (FAB-MS). FAB-MS spectrum can give the molecular weight information of the samples and inquire into the significant fragments from the samples.
THE PREPARATION,STRUCTURE AND PROPERTES OF Sr0.5Ca0.5CuO2
Yu Fang REN , Zuo Tao ZENG , Jian MENG , Ping HE
1991, 2(1): 37-40
[Abstract](206) [FullText HTML] [PDF 132KB](2)
Abstract:
Sr0.5Ca0.5CuO2 has been synthesized by the solid state reaction. The compound crystallizes in an orthorhombic unit cell, space group D2h17-Cmcm with a=3.444 Å, b=16.11 Å, c=3.868 Å. It decomposes shove 1038℃. Sr0.5Ca0.5CuO2 is a black p-type semiconductor with resistivity 53 Ω·cm at room tempersture.
SIMULTANEOUS DETERMINATION OF NEODYMIUM AND PRASEODYMIUM BY ZERO-ORDER AND FOURTH-ORDER DFRIVATIVE SPECTROPHOTOMETRY
Nai Xing WANG
1991, 2(1): 41-44
[Abstract](170) [FullText HTML] [PDF 977KB](2)
Abstract:
With derivative spectrophotometric method, the complexes of lanthanides with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) in the presence of octylphenol poly (ethyleneglycol) ether (TX-100) were studied. It is found that the maximum absorption of fourth-order derivative spectra of the neodymium complex by 4f electron transitions is at 579 (+) nm and 582 (-) nm with molar derivative absorptivities of 5.2×103 l·mol-1·cm-1. The maximum absorption of the zero-order derivative spectra of the complexes for neodymium and praseodymium is at 580nm, the molar absorptivities are 1.47×105 l·mol-1·cm-1 for Nd and 1.26×105 l·mol-1·cm-1for Pr. The component ratio of the complex is Nd:5-Br-PADAP=1:4. Beer's law is obeyed in the range of 0-3.75μg of Nd and Pr in 25ml of solution. The method has been used for the simultaneous determination of Nd and Pr in four synthetic samples and the results obtained are satisfactory.
NONAQUEOUS SERS:IMIDAZOLE IN METHANOL SOLUTION AT A SILVER ELECTRODE
Ren Ao GU , Ya Ping ZONG , Xiao Kun HU
1991, 2(1): 45-46
[Abstract](179) [FullText HTML] [PDF 375KB](2)
Abstract:
This paper emphasizes the observation of SERS spectra of imidazole/LiCl in methanol solution at a silver electrode and a qualitative explaination of the relationship between HERS spectra and molecular vibrational modes, and the relationship between SERS spectrum in aqueous and that in nonaqueous system.
CONVERSION OF ACETALS AND KETALS TO CARBONYL COMPOUNDS PROMOTED BY ZrCl4-NaBH4
Shao Zu WU , Hui Dong WANG , Ning CHENG
1991, 2(1): 47-50
[Abstract](183) [FullText HTML] [PDF 141KB](2)
Abstract:
In our study on the chemistry of ZrCl4-NaBH4, we have found that aldehydes and ketones can be regenerated from acetals and ketals at 30℃ in Et2O in high yield The reaction mechanism was discussed.
STUDIES ON THE REACTION OF ORGANOTELLURONIUM SALTS
Qi ZHONG , Yu Long CHEHG , Jian Guo SHAO , Chang Qing LIU
1991, 2(1): 51-54
[Abstract](169) [FullText HTML] [PDF 152KB](2)
Abstract:
The structural studies of the telluronium saltrformation between dibutyl telluride and secondary α-bromo compounds and the use of the obtained salts for the olefination of carbonyl compounds were reported.
A SNIFTIRS STUDY OF THE BENZOQUINONE-BENZOHYDROQUINONE REDOX SYSTEM IN AQUEOUS SOLUTION
Jin Kua YOU , Hui Huang WU
1991, 2(1): 55-56
[Abstract](184) [FullText HTML] [PDF 117KB](2)
Abstract:
The in-situ FTIR spectroscopic results show that a hemi-ketal intermediate may be produced in the electroreduction of benzoquinone or electro-oxidation of benzohydroquinone, which provides a valuable insight into the mechanism of the redox process.
A NEW KIND OF SURFACTANT:LONG-CHAIN ALKYLTRIPHENYLPHOSPHONIUM HALIDES Ⅲ.AN“ABNORMAL”QUENCHING OF PYRENE FLUORESCENCE BY PHOSPHONIUMS WITH DIFFERENT LENGTHS OF ALKYL CHAIN
Yun Bao JIANG , Jin Gou XU , GUO Zhen CHEN
1991, 2(1): 57-58
[Abstract](185) [FullText HTML] [PDF 111KB](2)
Abstract:
A study of the quenching of pyrene fluorescence by a series of alkyltriphenylphosphonium bromides indicated the coiling conformation of ionic surfactant in aqueous solution. Formation of pyrene excimer in cetyltriph-enylphosphonium solution strengthened the conclusion.
MINATION OF STABILITY CONSTANTS OF THE COORDINATION COMPOUNDS OF Au (Ⅲ)-2-MERCAPTOPYRIDINE-1-OXIDE AND METHYL DERIVATIVES——METHOD OF DUAL-WAVELENGTH CORRESPONDING SOLUTIONS
Yang CAO , Bao Lin SONG , Cheng ZENG
1991, 2(1): 59-62
[Abstract](190) [FullText HTML] [PDF 2374KB](3)
Abstract:
In this paper, we report the deductive formula used for the method of dual-wavelength corresponding solutions under condition of having ligand interference and the stability constants of three new coordination compounds [AuL2]+ determined with this method. The stability of the three compounds, the necessity of controlling pH in experimental systems and the advantage of this method are discussed in detail.
A SIMPLE METHOD TO CALCULATE RESONANCE ENERGY
Lu Bing YUAN , Yong DING
1991, 2(1): 63-64
[Abstract](184) [FullText HTML] [PDF 69KB](2)
Abstract:
A very simple method to calculate resonance energies of conjugated hydrocarbons by counting carbon numbers was introduced.
THEORETICAL STUDIES ON THE INVERSION REACTLON OF HYDROXY LAMINE H2NOH
Yun Zhu HAN , Cheng Da CHAO
1991, 2(1): 65-66
[Abstract](260) [FullText HTML] [PDF 73KB](2)
Abstract:
The inversion reaction of hydroxy lamine was investigated by using the ab initio intrinsic reaction coordinate (IRC) method with 4-31G basis set. Our results indicate that the ∠H1NO changes arastically in the vicinity of the transition state while the other bond angles and bond lengths change little throughout the reaction process.
SYNTHESIS AND CHARACTERIZATION OF A SERIES OF NOVEL INORGANIC MICROPOROUS CRYSTALS,BePO4-CIn(n=4-7).
Long YU , Wen Qin PANG
1991, 2(1): 67-70
[Abstract](199) [FullText HTML] [PDF 112KB](2)
Abstract:
A series of novet beryllophosphate zeolites, named BePO4-CIn (n=4-7), are synthesized hydrothermally and characterized with X-ray powder diffraction, IR spectra, SEM, thermat analysis and ion-exchange.
COMPLEXES OF MESO-TETRASUBSTITUTED PHENYLPORPHYRIN WITH YTTRIUM ACETYLACETONATE
Guo Fa LIU
1991, 2(1): 71-72
[Abstract](177) [FullText HTML] [PDF 90KB](1)
Abstract:
The complexes of meso-tetrasubstituted phenylporphyrin with Yttrium acetylacetonate were prepared by reaction of Y (acac) 33H2O with H2 (g) Tpp and were characterized by elemental analyses, ultra-violet, infrared spectra and thermal analyses.
STUDY ON RULE OF THE BOILING POINTS OF 1-HALOALKANES
Ping MEI , Cai Hua NI , Ye Gao YING
1991, 2(1): 73-74
[Abstract](177) [FullText HTML] [PDF 98KB](1)
Abstract:
There are many reports on the study of boiling point of paraffins, but less work has been done about those of alkylhalides. Recently, J. Correia
PHOTOVOLTAIC BEHAVIOURS OF THE COVALENTLY LINKED PHTHALOCYANINES DERIVATIVES
Jing Mei XU , Xu Rui XIAO , Shu Yin SHEN , Hui Jun XU
1991, 2(1): 75-76
[Abstract](165) [FullText HTML] [PDF 105KB](1)
Abstract:
The photovoltaic behaviours of thin films of novel photosensitizer consisting of covalently linked phthalocyanine (Pc) and anthraquinone (AQ) were studied in 0.1mol/L Na2SO4 solution. The results revealed that the higher photovoltage and photocurrent have been obtained due to light induced intra-molecules fast electron transfer in linked Pc-AQ compounds. The effects of different spacer chains between Pc and AQ molecules on photovoltaic behaviours were also discussed.
PHOTOELECTROCHEMICAL BEHAVIOR OF POLYANILINE FILM
Qing Song YU , Zheng TAN , Fo Song WANG
1991, 2(1): 77-80
[Abstract](151) [FullText HTML] [PDF 133KB](1)
Abstract:
The photoelectrochemical behavior of polyaniline (PAn) film was studied in aqueous electrolyte solution containing Fe (CN) 63-/Fe (CN) 64- redox couple. It was found that PAn films possess the properties of p-type semiconducter and a cathodic photocurrent as high as 700μA/cm2 was observed when irradiated under polychromatic light of 100mW/cm2.
SYNTHESIS AND CHARACTERIZATION OF NOVEL MICROPOROUS ALUMINOPHOSPHATES.
Long YU , Wen Qin PANG
1991, 2(1): 81-84
[Abstract](172) [FullText HTML] [PDF 139KB](1)
Abstract:
A series of novel aluminophosphates, named AlPO4-CJn (n=2-5), has been synthesized hydrothermally from R-Al2O3-P2O5-H2O systems (R=organic amine molecules), and characterized by means of X-ray powder diffraction, infrared, SEM, XPS, composition and thermal analyses.
NONLINEAR OPTICAL STUDY OF Fe2O3 UFP SOL
Bing Suo ZOHU , Liang Zhi XIAO , Yan ZHANG , Tie Jin LI , Jia Long ZHAO , Li HAN , Hao Sheg FEI
1991, 2(1): 85-86
[Abstract](212) [FullText HTML] [PDF 105KB](2)
Abstract:
In this letter, Fe2O3 UFP (Ultrafine Particles) hydrosol and organosol with high third order optical nonlinear susceptibility (3) have been reported for the first time. The surfacial modification of Fe2O3 UFP with dodecylbenzenesulfonate ions (DBS) can enhance the nonlinear optical response through interfacial confinement of electron motion. The involved mechanism is discussed.
THE DISMUTATION OF SUPEROXIDE ANION BY COPPER (Ⅱ) COMPLEX OF 1,4,7,10-TETRAAZACYCLOTRIDECANE-11,13-DIONE——A KINETIC STUDY BY MEANS OF PULSE RADIOLYSIS
Meng Chang SHEN , Shou Rong ZHU , Qin Hui LUO , An Dong LIU , Hong Chun GU , Feng Mei LI , Shao Jie DI
1991, 2(1): 87-88
[Abstract](180) [FullText HTML] [PDF 61KB](1)
Abstract:
The dismutation kinetics of superoxide anion by copper complex of 1, 4, 7, 10-tetranza-cyctotridecane-11, 13-dione was studied by pulse radiolysis. The dismutation rate constants at various pH and concentration of complex were obtained.
ELECTRONEGATIVITY TOPOLOGICAL INDEX AND ITS APPLICATION IN CORRELATION WITH MX,MX2,MX3,MX4 MOLECULAR PROPERTIES
Yong DING , Shi Hua WANG
1991, 2(1): 89-90
[Abstract](185) [FullText HTML] [PDF 63KB](2)
Abstract:
A New electronegativity topological index is defined and used to correlate with properties of MX, MX2, MX3, MX4.
DECAY FREQUENCY SPECTRA:INTEGRAL TRANSFORM OF NONLINEAR PROCESS TIME DOMAIN SIGNALS
Shu Kun LIN
1991, 2(1): 91-94
[Abstract](159) [FullText HTML] [PDF 111KB](1)
Abstract:
Decay frequency (DF) spectra are defined as spectral distribution of decay constants with oscillatory frequency as linewidth contributor. A mathematical strategy of integral transformation to construct DF spectra is reported. DF spectra are complementary to Fourier spectra.
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