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中文
Table of Content
24 September 1994, Volume 15 Issue 9
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Articles
Phase Diagram of EuI
2
-RbI Binary System
WANG Lin-Tong, WANG Shi-Hua, ZHAO Xin-Hua
1994, 15(9): 1263-1266.
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The phase diagram of EuI
2
-RbIbinary system has been studied by DTAand X-ray powder diffraction.It is a complicated eutectic system with four compounds─two congruent melting compounds RbEu2I5 and RbEuI
3
and two incongruent melting compounds Rb
3
EuI
5
and Rb
4
EuI
6
.The structure of Rb
3
EuI
5
belongs to a cubic system with a=1.0124(1)nm, and Rb
4
EuI
6
belongs to a tetragonal system with a=1.3719(5)nm, c=0.6458(5)nm.
Studies on Silicious ZSM-5 Filled Silicone Rubber Membranes(Ⅲ)─Adsorption,Desorption and Pervaporation Properties on Pure Solvent
CHEN Xin, PING Zheng-Hua, DING Ya-Di, LONG Ying-Cai
1994, 15(9): 1267-1271.
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The studies of adsorption, desorption and PVproperties on ethanol and water through silicalite-Ⅰfilled PDMSmembranes indicate that the adsorption capacity and PVflux on ethanol are distinctly larger than those on water, t he attainment of adsorption and desorption equilibrium on ethanol is quicker than that on water. DSCtest shows that m. p.of acetone which adsorbed on membranes whether filled or not filled with silicalite-Ⅰare raised up, which indicates that there is a strong interaction between organic solvent and PDMSmembrane.Moreover, as the zeolite content is about 30 wt%, there is a change that the continuity of silicone rubber matrix in zeolite filled membrane is destroyed.
Studies on Silicious ZSM-5 Filled Silicone Rubber Membranes(Ⅳ)─Effect of Zeolite Particle Size and Silicone Rubber Type on Separation Properties of Ethanol-Water Mixture by Pervaporation
CHEN Xin, PING Zheng-Hua, DING Ya-Di, LONG Ying-Cai
1994, 15(9): 1272-1275.
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The separation properties of ethanol-water mixture through polydimethylsiloxane(PDMS)membranes filled with silicalite-Ⅰtreated under steam, in which the zeolite particle size is 15 μm and 5μm, as well as acid treated silicalite-Ⅰ filled with different type silicone rubber membanes have been studied.The results show that the decrease of zeolite particle size is not favourable to the selectivity of ethanol-water mixture and the separation properties of ethanol-water mixture through different type of silicone rubber membrane filled with acid leached silicalite-Ⅰare related to the property of silicone rubber itself.
Crystal Structure and Luminescence Properties of Y
2
O
3
-Nb
2
O
5
-B
2
O
3
:Eu
3+
,Bi
3+
Phosphors
ZHANg Jing-Jun, ZHOU Shi-Hong, SU Qiang, FAN Sheng-Chun
1994, 15(9): 1276-1279.
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In this paper, Y
2
O
3
-Nb
2
O
5
-B
2
O
3
(2), Y
0.93
Eu
0.07
)
2
O
3
-Nb
2
O
5
·B
2
O
3
(4) and(Y
0.91
Eu
0.07
Bi
0.02
)
2
O
3
-Nb
2
O
5
-B
2
O
3
(5)phosphors were prepared by usual solid state reaction at 1200℃. The luminescence properties of these samples with fergusonite structure are reported and discussed. Under 268 nm excitation, Y
2
O
3
-Nb
2
O
5
-B
2
O
3
(2)shows much brighter blueviolet luminescence due to 1T1-1A1 level transition of NbO
4
group with a maximum at 410 nm.The B
2
O
3
in the system can reduce the reaction temperature and increase the emission intensity of NbO
4
group and Eu
3+
.The energy transfer from NbO
4
to Eu
3+
and from Bi
3+
to Eu
3+
is observed in(Y
0.91
Eu
0.07
Bi
0.02
)
2
O
3
-Nb
2
O
5
-B
2
O
3
(5)phosphor, so that the red emission of Eu
3+
is enhanced sensibly.
Studies on the Photochemical Reactions Catalyzed by Metalloporphyrin Complexes(Ⅲ)─Kinetics of Photoassisted Oxidation Reaction of Methanol by Metalloporphyrins
YANG Guo-Yu, WANG Qing-Min, SUN Jin-Feng, ZHAO Qian YU Lian-Xhng, CAO Xi-Zhang
1994, 15(9): 1280-1284.
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In deaerated solution of water-methanol or water-methanol-pyridine system, trivalent ions(Co(Ⅲ)and Mn(Ⅲ))porphyrins were reduced to divalent ions on illummination of light with simultaneous oxidation of methanol. The kinetic study on the photoreduction revealed that the reduction rate of Co(Ⅲ)followed the pseudo-first-order rate expression at 20℃ and pH 2 to 13 in the presence of excess methanol. The observed rate constants were dependent on [CH
3
OH] and pHvalues.The possible mechnisms for the photoreduction of metalloporphyrins were discussed.
The Phase-Transfer Chemistry of Heteropolyanions(Ⅳ)─The Coordination Reaction of Heteropolyanions with NO
WANG En-Bo, LIU Xia, WANG Zuo-Ping, XU Lin, GAO Li-Jaun
1994, 15(9): 1285-1287.
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In this paper, the coordination reaction between the substituted heteropolyanionswith Keggin structure{[XM
11
O(39)Z]
n-
, X=Si, P;M=Mo, W;Z=Co(
2+
), Ni(
2+
)}, and Dawson structure{[P
2
W
17
O
61
Co]
8-
} and the small inorganic molecules nitrogen oxide in a nonpolar solvent is studied by means of the phase-transfer chemistry of heteropolyanions, electronic absorption spectra and electron spin resonance (ESR).The experimental results show that, except the heteropolyanions for [PMo
11
O(39)Co]
5-
, the others can form coordination compounds with nitrogen oxide.
A New Characterization Parameter for Molecular Conformation Change of Proteins in Reversed-phase Liquid Chromatography
SHI Ya-Li, MA Feng, GENG Xin-Du
1994, 15(9): 1288-1291.
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The Zvalue of the stoichiometric displacement model for retention can be used to be a new chracterization parameter for the molecular conformation of biopolymers caused by temperature in reversed-phase liquid chromatography(RPLC).It was found that when 2-propanol 44%(V/V)-formic acid-water was selected as a mobile phase, the Zvalues of four kinds of completely denaturated proteins decreased with the increase of temperature and the Zvalue changes would be directly proportional to the reciprocal of absolute termperature (1/T).The chracterization of the change in the molecular conformation of biopolymers in the instance can be obtained by means of the difference between the two slopes of each proteins from the plots of Zvs. 1/T, and the larger the difference, the greater the change in the molecular conformation of the protein is. The abrupt change temperatures for each proteins can be calculated from the intersect of the two straight lines. Compared to the characterization of molecular conformation of proteins with the plot of 1gk'(k'is the capacity factor)versus 1/T, the plot Zversus 1/Tis not only valid for each type of proteins, but also is more accurate.
The Determination of Ionization Constants of Polyprotic by Using Evolving Factor Analysis and pH-Spectrophotometric Data
CONG Pei-Sheng, ZHU Zhong-Liang, LI Tong-Hua
1994, 15(9): 1292-1296.
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Anew method for determining the ionization constants of polyprotic acid by using Evolving Factor Analysis with chemical equlibrium on pH-spectrophotometric data is proposed. It is based on the fact that a species which first appears must be the first to disappear in a polyacid equlibrium system.The method was tested by the ionization constants of Alizarine Red Sand Chromazurol S.The criterion for correctly locating the regions of the existence of a given component is also discussed in detail. The results show that this method is stable and reliable and has a fast convergence speed. The obtained constants are consistent with those cited in references.Another advantage of this method is that it can provide the absorbance curve of every component simultaneously in the system and is suitable for a great deal of color complexing systems.
A Study of Glassy Carbon Material as Platform with Graphite Furnace Atomic Absorption Spectrometry
ZHUANG Zhi-Xia, YANG Peng-Yuan, WANG Xiao-Ru, XUE Ru, HUANG Ben-Li
1994, 15(9): 1297-1300.
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The use of glassy carbon material(GC) as the platform with graphite furnace atomic absorption spectrometry is described.In the present work, the prelimited experimental gathered by GCplatform in combination with pyrolylic graphite coated tube is reported with regard to analytical characteristic, lifetime, sesitivity and reproducibility of determination, chemical stability and matrix interferences for determination of volatile element Cd and less volatile element Cu.Overview and comparison of the surfaces on GCand graphite platform by scanning electron microscopy are presented.
Sensitized Room-Temperature Phosphorescence of Biacetyl by Naphthalene in Micellar Systems
XIE Jian-Wei, XU Jin-Gou, CHEN Guo-Zhen
1994, 15(9): 1301-1304.
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Micelle organizes the donor and acceptor molecules into a discrete volume region, facilitates the energy transfer and enhances the intensity of sensitized RTP.This paper reports the sensitized RTPof biacetyl by naphthalene in SDSmicellar solution, and indicates that the intensity of sensitized RTPwas correlative with the Poisson distribution and determined by values of P
D
less
×P
A
less
which is the probability of less donor and less acceptor occurred in the same micelle.The linear range of detection is 0-8.0×10
-5
mol/L.Typically, the limit of detection for naphthalene in SDSis 6.5×10
-8
mol/L.
Simulaneous Spectophotometric Determination for Multicomponent Phenols Compounds by Partial Least Squares Method
FAN Hua-Jun, ZHANG Wei, YAN Rong, LIN Xiao-Yi
1994, 15(9): 1305-1308.
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Paradioxybenzene, resorcinol, pyrogallol and paranitrophenol can react with copper(Ⅱ)and pyridine to from stable ternary complexes, and the ternary chromogenic system has been studied. Principle of partial least squares was introduced. Results of simultaneous determination for multicomponent phenols compounds in mixed samples and environmental samples were predicted spctrophotometrically by partial least squares method.Predictive results and recovery are satisfactory.
A Study of Human Albumin Labelled by Silver and Lead with Ion-Selective Electrodes
SHI Sheng-Hua, LIU Peng, HAO Cai-Li, FENG Bin, WANG Yan, LI Wei
1994, 15(9): 1309-1313.
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The complex equilibria of Ag-human albumin (HSA) and Pb-HSAwere studied by ion-selective electrodes.It was clearly proved that both Ag and Pb with HSAformed mononuclear complexes MAand MA2 respectively.The stability products of Ag-HSAcomplexes are β
11
=4.4×10
7
and β
12
=1.0×10
12
;and that of Pb-HSAcomplexes are β
11
=3.1×10
5
, β
12
=2.0×10
9
.According to the immunochemical reaction of HSAwith albumin antiserum (GAHA), the linear range of determing GAHA(titer 1 : 40)is respectively 0.2-2.0μLand 0.4-2.8μLwhen HSAis labelled by Ag and Pb; moreover the linear range of determining HSAis respectively 0-2. 9×10
-8
mol/Land 0-7.3×10
-7
mol/Lwhen GAHAis labelled by Ag and Pb.
Studies on the Polarographic Adsorptive Wave of Heteronuclear Complex of Rare Earth-Cobalt-Alizarin Complexon
CUI Yi, LI Nan-Qiang
1994, 15(9): 1314-1316.
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In the 0.4 mol/Lacetate buffer solution, at pH4.6, a sensitive adsorptive wave of heteronuclear complex of RE (Ⅲ)-Co(Ⅱ)-alizarin complexon(ALC)was obtained by single-sweep polarography with the exception of Sc, Lu, Yb and Tm, The peak height of derivative wave is proportional to CLa from 1. 0×10
-8
to 2.0×10
-6
mol/L.By using of photometry and analysis of the complex precipitate, the composition of complex may be LaCo·(AtC)
2
(Ac)
2
Cl
2
Na
7
·4H
2
O;On the mercury electrode, the adsorptive intensity can be arranged as : LaCo(ALC)
2
>La
2
(ALC)
2
>CoALC>ALC.The occupied area of each heteronuclear complex ion on the surface of electrode was detemnined as 1.2- 1.4 nm
2
which is commensurate with one ALCion area, The possible constitution may be a sandwich structure.
Studies on the New Packings of High Performance Ion Exchange Chromatography for the Separation of Proteins(Ⅱ)─The Synthesis and Characteristics of the New Packings or Weak Cation Exchange Chromatography
CHANG Jian-Hua, HAN Ya-Ping
1994, 15(9): 1317-1321.
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The studies on the synthesis and chromatographic characteristics of three kinds of new packings of high performance weak cation exchange chromatography for the separation of proteins have been reported on the basis of previous work.The silica reacted with γ-glycidoxypropyltrimethoxy silane, then the product reacted with polyethyleneimine and yielded a crosslinked product, which reacted with a cycloanhydride to give WCX-5 and WCX-6 packings;If the crosslinked product reacted with polysuccinimide, followed by hydrolysis, the WCX-7 packings have been prepared.The crosslinkage of packings ligand could raise the recovery of the bioactivity of proteins, The recovery of the bioactivity of lysozyme is over ninety four percents.The column capacity of WCX-7 packings is bigger than that of other two packings because the crosslinked ligand of WCX-7 is more than that of other two. The reten tion rule of some proteins on the WCX-7 column is different from that of the ordinary WCXcolumn.The retention of lysozyme and Cytochrome-c increases with the increase of pHvalue, The separation property of WCX-5 is the best.
Synthesis and Characterization of Schiff Base Complexes of Mixed Diorganotin Dichlorides
LIU Bao-Dian, XU Yong-Xiang, BAO Ming, HE Qing-Lin
1994, 15(9): 1322-1326.
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Twenty-four new addition complexes of type R′R″SnCl
2
·2- HOC
6
H
4
CH=NC
6
H
4
Rand R′R″SnCl
2
·(2-HOC
6
H
4
CH=NC
6
H
4
R)
2
have been synthesized by the reactions of mixed diorganotin dichlorides, R′R″SnCl
2
(where R′= Et, Bu, Bz;R″=Ph;R′= Et, R″= Bu), with N-arylsalicylideneimines, 2- HOC
6
H
4
CH=NC
6
H
4
R(where R= H, 4- CH
3
, 4- OCH
3
, 3-CH
3
, 4-OH).The complexes are non electrolyte in nitrobenzene.NMR (1 H,
13
C), TG-DSCand XRDstudies indicate the ligands coordinate to Sn atom via phenolic Oatom rather than imide Natom, under different reaction conditions, the same organotin compound and the same Schiff base can form the complex to have different coordination number.
Studies on Chiral Thiophosphoric Acids and Their Derivatives(Ⅻ)─Synthesis of the Optical Isomers of Insecticidal O-Methyl O-Phenyl S-Propyl Phosphorothiolate and Their Absolute Configuration
TANG Chu-Chi, MA Fu-Peng, ZHANG Mian-Ji, LI Zhen
1994, 15(9): 1327-1330.
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acemic O-methyl O-phenyl thiophosphoric acid 2 has been successfully resolved through its quinine and brucine salts in methanol solution by the fractional crystallization method. The optically active acids, ( +)-2 and(-)-2, react with propyl bromide in the presence of EtONa/EtOHto give(-)-O-methyl S-propyl O-phenyl phosphorothiolate 1 and(+)-1, respectively.The absolute configuration of the optically active 1 has been established as(-)-(S)and(+)-( R) by the chemical correlation method.
Studies on the Readions of Iron Carbonyl-Mercaptan(Thiophenol)-Grignard Reagent System with Benzoyl Chlorides─Syntheses and Structures of Some Substituted μ- Benzoyl Fe/S Complexes
SONG Li-Cheng, HU Qing-Mei, CAO Xi-Chuan
1994, 15(9): 1331-1334.
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The in situ reactions of the active complex salts [(μ-CO)(μ- RS)Fe
2
( CO)
6
]
-
·Mg
+
Br, formed from triiron dodecacarbonyl, mercaptan or thiophenol and Grignard reagent EtMgBr, with o-or m-chlorobenzoyl chloride in THFat room temperature gave six new substituted μ-benzoyl Fe/Scomplexes with general formulas of(μ-RS) (μ-o-ClC
6
H
4
CO) Fe
2
( CO)
6
and( μ- RS)(μ-m-ClC
6
H
4
CO) Fe
2
(CO)
6
(R=n-Bu, t-Bu, Ph), which were fully characterized by C/Hanalysis, IRand
1
H NMRspectroscopy.
Immobilization of Porcine Pancreas Lipase and Its Catalyzed Transesterification Reaction of Methyl Butyrate and
1
-Butanol in Organic Systems
XIE Zhi-Dong, HE Bing-Lin, LU Xian-Yu
1994, 15(9): 1335-1339.
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Series of macroporous cross-linked polymers of styrene with divinylbenzene and their functionalization products were synthesized. Effects of degree of cross-linking, amount of pore-generating agent and different aminating agents on immobilization of porcine pancreas lipase(PPL)were studied.The best carrier was selected.Transesterification of methyl butyrate with 1-butanol was catalyzed by the free and immobilized PPL, it was found that the catalytic activity of immobilized PPLin organic systems was two times as high as that of the free PPL.
A New Field in Organic Chemistry ─Studies on the solid State Photochemistry
MENG Ji-Ben, WANG Yong-Mei
1994, 15(9): 1340-1345.
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In this paper, a new field of organic photochemical reaction in solid state with an important significance and characteristics is reviewed;We have investigated bimolecular photoreactions between two different organic molecules, such as a series of tryptophans and the nucleic acid beses with fused polycyclic aromatic hydrocarbons.The result shows that the reactions exhibit a high stereo-and regio-selectivity.This is a new effective synthetic method.The reaction mechnism was also postulated.By using a crystal lattice-controlling substance a series of compounds for which the photoreaction can not take place may undergo the regio-and stereo-selectivity photoreaction.The method can be employed to synthesize optical active Dor Lcompounds which need not resolution.The charge transfer(C-T)complexes and molecular compounds were also investigated in solid state photoreaction.
Synthesis of 1-Aroyl-3-alkyl-6-hydroxy-6-aryl Fulvenes
JIAO Lun-Ji, DONG Yu-Bin, MA Yu-Dao
1994, 15(9): 1346-1348.
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Ten new fulvenes have been synthesized by the reactions of 6, 6-dialkylfulvenes and 6-ferrocenylfulvene with methyllithium or aryllithiums followed by treatment of aroyl chloride. On the basis of
1
H NMR, IRand elemental analysis, their structures were proposed.
Fabrication and Photovoltaic Property of Porous Silicon
WANG Bao-Hui, WANG De-Jun, LI Tie-Jin
1994, 15(9): 1349-1352.
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Using a special electrolytic cell, we prepared a series of porous silicons with different surface structures by anodizing n-type single crystal silicon in HFsolution.The surface photovoltaic spectroscopy(SPS)of the porous silicons which were formed under different conditlons was recorded.The results show that SPSof the porous silicon is obviously different from that of the non-etched silicon and the main peak wavelength has an evident blue shift relative to that of the non- etched silicon, The SPSdepends on the anodizing conditions which include HFconcentration and anodizing time.The shift is attributed to quantum confinement effects in tl1e silicon quantum wires formed in porous silicon.This observation supports the existence of the quantum size effect in porous silicon.
Solid-Liquid Phase Equilibria and Excess Gibbs Free Energies for p-Xylene+Cyclohexane,p-Xylene+Dimethyl Sulfoxide
CHE Guan-Quan, HUANG Zhong-Qi, LUO San-Lai, YUN Feng-Cun, ZOU Yong-Kuang
1994, 15(9): 1353-1356.
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Melting temperatures have been measured and the solid-liquid phase diagrams were constructed for p-xylene+cyclohexane, and p-xylene+ dimethyl sulfoxide.They are simple eutectic systems.Eutectic temperatures and compositions are 240. 96 K, 0.825 and 280.99K, 0.53Ofor(1-x)p-C
6
H
4
(CH
3
)
2
+xC
6
H
12
and(1-x)p-C
6
H
4
(CH
3
)
2
+x(CH
3
)
2
SO, respectively. Excess molar Gibbs free energies were calculated at 313.15 K.The largest values of are 233.7 and 1224. 8/mol for(1-x)p-C
6
H
4
(CH
3
)
2
+xC
6
H
12
and (1-x)pC
6
H
4
(CH
3
)
2
+x (CH
3
)
2
SO, respectively, showing positive deviations from ideal-solution behvior.The latter deviation is very large, especially.
Studies on the Synthesis,Structure and Catalytic Decomposition of Hydrogen Peroxide of Trilacunary Heteropoly Compound K
8
[P
2
W
18
Mo
2
Co
2
(H
2
O)
2
O
68
]·MoO
6
·15H
2
O
QI Xing-Yi, ZHANG Heng-Bin, LI Shu-Jia, WANG Guo-Jia, WU Yue
1994, 15(9): 1357-1360.
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In this paper, the synthesis of K
8
[ P
2
W
18
Mo2Co2(H
2
O)
2
O
68
] ·MoO
6
·15H
2
Owas introduced;the crystal structure and valence states of coordinated atoms were deterimined by X-ray, IR, UV-Vis and XPSmethods;the performance in catalytic decomposition of hydrogen peroxide was studied and compared with those of K
10
[P
2
W
18
Co4(H
2
O)
2
O
68
]·20H
2
Oand Na6P
2
W
18
O
68
·xH
2
O as well.
Studies on the Catalytic Action of Imidazole and Its Derivativs in the Reactlon of β-Carotene Oxidative Decomposition
ZHANG Zhi-Hui, CHEN Lan, ZHU Zhi-Ang, RUAN Wen-Juan, CHEN Rong-Ti, JIAN Dong-Qing
1994, 15(9): 1361-1365.
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The catalytic action of imidazole and its derivatives in the reaction of β-carotene oxidative decomposition has been studied for employing meso-tetramesityl-porphinatoiron (Ⅲ) chloride(FeTMPCI)as the catalyst and m-chloroperbenzoic acid as the oxidant in dichloromethane by means of Beckmann Du-8Bspectrophotometer.Imidazole and its derivatives are not only the axial coordinate ligand but also a kind of catalyst.The reasonable mechnism of the reactions was postulated.The data were simulated with IBM-PCcomputer, the reaction rates were obtained. the effect of reaction condition on the rate of reaction was discussed.
Dynamic Behavior of Nonlinear Chemical Reaction in Low Dimension Medium
WAN Rong, LI Ru-Sheng
1994, 15(9): 1366-1368.
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The dynamic behavior of the trimolecular autocatalytic reaction A+2X?3Xin one and two dimensions is studied by numerical simulations.It is found that the asymptotic behvior of the reaction can be, depending on the microscopic reaction rules, quite different from or the same as the equilibrium limit predicted by classical chemical kinetics(mean-fieldtheory)in both one and two dimensions.
Studies on Electronic Structure and Catalytic Properties of Anderson and Waugh Heteropoly Anions
YANG Sheng-Yong, XIAO Shen-Xiu, CHEN Tian-Lang
1994, 15(9): 1369-1372.
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The electronic structures of two heteropoly anions, (IMo
6
O
24
)
5-
(Anderson-type)and(NiMo
9
O
32
)
6-
(Waugh-type), were calculated by SCC-DV-X
α
method, and the catalytic properties were investigated.The results indicated that both kinds of heteropoly anions can be used as catalysts.The active centers are O
t
(terminal oxygen), Oc(links Iand Mo)for(IMo
6
O
24
)
5-
, and O
t
, Ni, O
c
(links Ni and three Mo atoms) for(NiMo
9
O
32
)
6-
. But bridge oxygen(O
b
)is not active, which is different from that of the Keggin-type.
^^Effect of CeO
2
on Surface Oxygen Desorption and Reproduction of Mn
2
O
3
LUO Meng-Fei, YUAN Xian-Xin, ZHOU Lie-Hua
1994, 15(9): 1373-1376.
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In this paper, the desorption properties of surface oxygen over Mn-Ce-Oand its reproduction were investigated by means of TPD-MS. The oxidation activity of methanol on these catalysts was studied under different concentrations of oxygen. There are three peaks in the TPD-MSspectra of Mn-Oand Mn-Ce-Ocatalysts, the first two are attributed to the absorbed oxygen and the last one is ascribed to the lattice.oxygen. CeO
2
can not change the position of the O
2
-TPDfeature peaks of Mn
2
O
3
, but evidently increases the amount of surface absorbed oxygen.The addition of CeO
2
increases the capacity of surface oxygen reproduction of Mn
2
O
3
.The oxidation activity of methanol on these catalysts is relative to the absolute amount of surface desorption oxygen of each catalyst.The stronger the reproduction of the surface absorbed oxygen of the catalysts, the less the catalytic oxidation activity is affected by the vapor phase oxygen.
In situ FT-IR Spectroscopic Study of Electrochemical Reduction of Thionyl Chloride on Pt Electrode
YOU Jin-Kua, ZHONG Wen-Long, LIN Zu-Geng
1994, 15(9): 1377-1380.
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An experimental technique has been designed which allows time resolved in situ FT-IRspectroscopic measurement of the reduction of the SOCl
2
.SO
2
Cl
2
, SO·SOCl
2
, (SO)
x
, Cl
3
Al(←OSCl
2
)are observed as intermediates in the electrochemical reduction of SOCl
2
on the Pt electrode.The results show that the intermediates are unstable and the further electrochemical reduction of SOCl
2+
2e→SO
2+
2Cl- is the rate determination step of SOCl
2
.According to the experimental result, the possibility of the electrochemical reduction steps of S
2
OCl
2
is discussed.
Quantum Chemical Study of Thermolysis of t-Butylether
HONG San-Guo, FU Xiao-Yuan
1994, 15(9): 1381-1384.
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AM1 method has been used to study the thermolysis of t-butylether.The results obtained show that these compounds can decompose into butylene and alcohol or phenols through an elimination involving four-center cyclic transition states. The activation energies of reactions, for R=CH
3
, CH
2
CH
3
, CH(CH
3
)
2
, CH
2
CN, C
6
H
5
, p-CH
3
OC
6
H
4
, p-NH
2
C
6
H
4
and p-NO
2
C
6
H
4
are 248.8, 245.5, 238.5, 216.4, 219.5, 217.9, 221.6 and 188.2 kJ/mol, respectively, which are consistent with the experimental values.
An ab initio Mo Study of the Isomerization and Dissociation of Nitryl Hydride
FENG Da-Cheng, WANG Zhen, WANG Bing-Ze, DENG Cong-Hao
1994, 15(9): 1385-1387.
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The results of an ab intio MOstudy of the isomerization and dissociation reaction of nitryl hydride(HNO
2
)has been reported. It is found that, at 6-31Glevel, the energy barrier from nitryl hydride HNO
2
to trans-HONOis 292 kJ/mol, and it does not dissociat to H+NO
2
or O+HNOeasily.
Preparation and TEM Micrographs of Multipattern Large-size Carbon Nanotubes
YU Rong-Qing, ZHAN Meng-Xiong, CHENG Da-Dian, ZHAI He-Sheng, YANG Shi-Yao, HUANG Rong-Bin, ZHENG Lan-Sun
1994, 15(9): 1388-1389.
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Large-size carbon nanotubes were prepared by a.c.arc-discharge method under an inert atmosphere.Multipattern images were obtained through transmission electron microscope.The hollow inner diameter and the distance between carbon layers in some nanotubes are larger than those previously reported. In particular, some special structural patterns were first observed.
The Implementation of I
h
Symmetry Reduction for X
α
Method and the Calculations of C
60
YU Wei-Zhou, ZHANG Ming-YU, LI Xiao-Tian
1994, 15(9): 1390-1392.
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In this paper, I
h
group symmetry reduction scheme has been programmized, and the electronic structure, the ionization potential and UVspectra for C
60
have been calculated by X
α
method.The results agree with experimental values.
Kinetic Studies on the Oxidation of Uranium(Ⅳ)in Nitric Acid Medium
AHOU Zu-Ming, ZHANG Ying-Jie, DU Hui-Fang
1994, 15(9): 1393-1395.
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The kinetics of oxidation of uranium(Ⅳ)in nitric acid medium by nitrite and air oxygen, respectively, has been investigated. The effects of concentration of uranium(Ⅳ), nitrate, hydrogen ion and nitrite in the aqueous solution or the oxygen in air on tl1e oxidation rate of uranium(Ⅳ)were examined.The oxidation rate of uranium(Ⅳ)increases obviously with increasing temperature and the apparent activation energies were 47 kJ/mol for nitrite and 91 kJ/mol for oxygen as the oxidant.The mechanisms of oxidation of uraniuni(Ⅳ)for both oxidation reaction were discussed.
Studies on the Phase Equilibria of the Four-component Systems of Na
+
,K
+
‖CI
-
,B
4
O
2-
7
-H
2
O at 25℃
YAN Shu-Wang, TANG Ming-Lin, DENG Tian-Long
1994, 15(9): 1396-1398.
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In this paper, the solubilities of the title systems and its sub-systems of the Na
2
B
4
O
7
-K
2
B
4
O
7
-H
2
Oat 25℃ are presented. Meanwhile, the solubility parameters at binary and ternary co-saturated points are given and the dry-salt diagram and water diagram of the four-component systems are also shown.
Studies on the Sulfonated EPDM Ionomers Neutralized with Amines
GU Xue-Rong, LUO Feng-Lan, ZHANG Guang-Hua, YANG Chang-Zheng
1994, 15(9): 1399-1403.
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Four different ionomers containing--SO
-
3
(19940936-1399-1.jpg)H
4-x
Et
x
ionic groups were prepared by neutralizing the sulfonated EPDM with ammonium hydroxide, ethylamine, diethylamine and triethylamine respectively.The elemental analysis, stress-strain, dielectric properties and density measurement data showed that the neutralization degree, tensile strength, temperature of β′relaxation peaks and the density of the ionomers all decreased with the increase of the ethyl group numbers(x)in different amines, which were utilized as a neutralizing agent.When x=0, relaxation peak splited into two relaxation peaks αand β, which indicated that the ionic groups(-SO
3
NH
4
)in the ionomers aggregated into compact ion clusters, and resulted in two phases morphology.However, in the case of x>1 and the precursor S-EPDM-H, the homogeneous phase morphology system was still maintained because the ionic groups only gathered into multiplets. As the number x increased, the volume of the ion pair increased and the positive charge of the nitrogen atoms decreased, hence the cohesionenergy of the ion pairs, as well as the rigidity of the multiplet and the densities of the samples decreased.
Pervaporation Separation of Organic-Aqueous Mixtures Using the Chitosan Membrane
LI Wen-Jun, MA Jing-Hong
1994, 15(9): 1404-1407.
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Pervaporation separation of dioxane-water and acetone-water mixtures has been studied by use of chitosan homogeneous and composite membranes. The results show that the membranes have an excellent selectivity and a permeation rate for the separation of the mentioned mixtures. For example, water in permeates is more than 99.5wt%, while the permeation rates are 946.5, 306.9g·(m
2
·h)
-1
for dioxane-water(60℃)and acetone-water (40℃)mixtures, respectively, when the feeds are close to azeotropic compositions.With increasing temperature, the increases of both in flux and separation factor have been observed.Employing the composite membrane, the fluxes have a more conspicuous increase than that of homogeneous membrane, meanwhile, the selectivities have an appropriate reduction.
Investigation of Interpenetrating Polymer Network Chelate Resin(Ⅰ)─Syntheses of Crosslinked Polystyrene-Polyacrylonitrile Interpenetrating Polymer Network
WANGYong-Jian, LIN Xue, YANG Yi-Zhong, HE Bing-Lin
1994, 15(9): 1408-1411.
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In this paper, crosslinked polystyrene─polyacrylonitrile interpenetrating polymer networks(IPN) have been prepared.The relationship between the interpenetrating percentage of resin and crosslinked percentage, weight fraction, pore structure and solvents were discussed.For the gel type resin, when the crosslinked percentages of the two networks are the same, the interpenetrating percentage is the best.For the macroreticular type, the effect of pore structure is remarkable.The results show that solvent is the most important factor for the IPNsynthese.
The Synthesis of Some Macroporous Crosslinked Polystyrenes and Their Adsorption Properties for Chlorophyll Copper
FAN Yun-Ge, LIU Yong-Ning, SHI Zuo-Qing, HE Bing-Lin
1994, 15(9): 1412-1415.
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The macroporous polymeric adsorbents(-Ⅶ)were synthesized by suspension homopolymerization of divinylbenzenes wtih various purities (56%-97.5%) or copolymerization of divinylbenzenes and styrene as well as a small amount of methyl acrylate in one example.The adsorbent(Ⅷ)was obtained by Friedel-Crafts acetylation of the crosslinked polystyrene-type resin(Ⅱ).The structural characterization of the adsorbents(Ⅰ-Ⅷ)were carried out by means of physical techniques and chemical methods.Their adsorption capacities to chlorophyll were determined in a batch test.The results showed that adsorbentsⅠⅧ could adsorb chlorophyll copper and their capacities depend on porous structures, specific surface areas, and polarities of these adsorbents.
Dynamic Light Scattering Study on Solution Properties of Phenolphthalein Polyaryl Ether Sulfones in Good Solvent
RAO Lei, MA Rong-Jiu, LIN De-Hou
1994, 15(9): 1416-1419.
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The solution properties of phenolphthalein polyaryl ether sulfones(PES-C)in good solvent DMFhave been studied by dynamic light scattering.The average decay rate is given by Γ=q
2
D
t
. The results show that diffusion of PES-Cmolecule in the system fits rigid-ball model. We obtained the diffusion coefficient of PES-Cmolecule as a function of the concentration and temperature. The hydrodynamic radii for the particle in the good solvent was calculated by means of Stokes-Einstein equation.The diffusion activation energy has been obtained from Arrehnius function, and it is not associated with concentration.
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