Loading...
Toggle navigation
CRCU
Home
About the Journal
Editorial Board
Editorial Board
Youth Executive Editorial Board
Instruction
Journal Online
Forthcoming Articles
Current Issue
Advanced Search
List of Issues
Most Downloaded
Most Read
Most Cited Articles
RSS Services
E-mail Alert
Subscribe
Contact Us
Table of Content
24 January 1990, Volume 6 Issue 1
Previous Issue
Next Issue
Articles
Preparation and Characterization of Chromium(Ⅲ)-Containing α-and β-Tungstosilicates
Peng Jun, Qu Lunyu, Zhang Baojian, Chen Yaguang
1990, 6(1): 1-6.
Abstract
(
)
PDF
(443KB) (
)
Related Articles
|
Metrics
Eight new compounds of α- and β- M
2
H
4
[SiW
16
Cr
2
(OH
2
)
2
O].xH
2
Otypes, where M=K, Me
4
N, Et
4
Nor n-Bu
4
N, and 0+6=6,were synthesized from trivacant heteropoly tungstate α-and β-[SiW
9
O
34
]
10
precursors, and characterized by elemental analysis, thermal gravimetric analysis, IR, UV-visible spectra, X-ray photoelectron spectroscopy(XPS), polarography, magnetic measurements and X-ray powder diffraction. The IRand UVspectra conJEirm that α-and β-[SlW
10
Cr
2
(OH
2
)
2
O
24
]
6-
isomers possess α-and β-Keg-gin structures. The differences between α-and β-isomers in IR, UVspectra and polarography are discussed.
Crystal and Molecular Structure of Guanidinium Pentamolybdobis (n-amylphosphonate)(CN
3
H
6
)
4
[(n-C
5
H
11
P)
2
Mo
5
O
21
]
Wang Xin, Liu Benyao, Ku Yihtong(Gu Yidong)
1990, 6(1): 7-13.
Abstract
(
)
PDF
(474KB) (
)
Related Articles
|
Metrics
The crystal structure of guanidinlum pentamolybdobis(n-ainylphcsphonate), which contains the longest carbon chain hitherto known, was determined by single-crystal X-ray diffraction analysis. It belongs to monoclinic, space group C2/c, Z=4, 0=18.857(2), b=12.170(1), c=18.294(2)λ.β=102.73(2), V=4095.2λ
3
.u= 140.34cm
-1
. The intensity data were collected on an Enraf-Nonius CAD4 diffractometer with MoKa radiation. The positions of all molybdenum and phosphorus atoms were determined by the direct method. The other non-hydrogen atoms were revealed by difference Fourier synthesis. The structure was refined by full-matrix least-squares procedure to a final Rvalue of 0.068. The structure of the anion is similar to [(CH
2
P)
2
Mo
5
O
21
]
4-
, [(NH
3
C
2
H
4
P)
2
Mo
6
O
21
]
2-
, [(n-C
3
H
7
As)
2
Mo
5
O
21
]
4-
, and [(C
3
H
5
As)
2
Mo
6
O
21
]
4-
. It consists of a ring of five distorted MoO, octahedra joined by edge-sharing, except for one pair which is joined by corner- sharing. The size of the Mo
6
O
16
ring is close to those of [(CH
3
P)
2
Mo
5
O
21
]
4-
and [(NH
2
C
2
H
4
P)
2
Mo
5
O
21
]
2-
and much smaller than those of [(n-C
2
H
7
As)
2
Mo
5
O
21
]
4-
and [(C
2
H
6
As)
2
Mo
6
O
21
]
4-
. The symmetry of the anion, however, to the same at those of its arsenic con-seners [(n- C
2
H
7
As )
2
Mo
5
O
21
]
4-
and [(C
3
H
5
- As )
2
Mo
5
O
21
]
4-
, but different from those of [(CH
3
P)
2
Mo
5
O
21
]
4-
and [(NH
3
C
2
H
4
P)
2
Mo
5
O
21
]
2-
. The average bond angles O-P-Owere estimated on the basis of assuiming that anion [(RP)
2
Mo
5
O
244
-could be formed.
Studies on Functionally Substituted n
5
-Cyclopentadienyl Transition-Metal Compounds-Synthesis and Crystal Structure of η
5
-CH
3
COC
5
H
4
W(CO)
3
CH
2
C
5
H
5
Song Licheng, Yang Hua, Hu Qingmei, Zhou Zhongyuan
1990, 6(1): 14-19.
Abstract
(
)
PDF
(406KB) (
)
Related Articles
|
Metrics
Reaction of benzyl chloride with η
5
-CH
3
COC
5
H
4
W(CO)
2
Na formed in situ from η
6
-CH
3
CO C
6
H
4
Na and W(CO)
2
gives η
6
-CH
3
COC
6
H
4
W(CO)
3
CH
2
C
5
H
5
. The single crystal structure of the product was determined by X-ray diffraction method. It crystallizes in the triclinlc space group P
1
with unit cell parameters a= 10.199(5),b=12.116(7), c=14.207(6)A;a=69.47(5),β=72.38(3),γ= 85.89(4);V= 1569.9A
3
, Dc= 1.98 g/cm
2
; Z=4. Least-square refinement led to final Rvalue of 0.0539 and Rw value of 0.0553, based on 3548 independent observed reflections.
Studies on the Solvent Effect of N-Carbamoyl-N-(1-Oxyl
2
,2,5,5-Tetramethyl-Pyrrolin-3-yl) Ureas
Zhang Ziyi, Wei Lulin, Wang Hanqing
1990, 6(1): 20-27.
Abstract
(
)
PDF
(543KB) (
)
Related Articles
|
Metrics
The electron spin resonance spectra of N-carbamoyl-N-(l-oxyl-2,2,5,5-tetramethyl-pyrrolin-3-yl) urea compounds in ten solvents with different polarities were determined. It was found that the hyperfine splitting constant ANand spin density p
N
. as well as the energy difference between two adjacent energy levels E of different pyrroline nitroxides in the same solvent increase with the increase of electron-withdrawing α-bility of the substituted groups on the aromatic ring. There was a linear correlation between A
N
and Reichardt E
T
value, and between A
N
and Z value as well. Such a linear correlation was also found between solvent viscosity n and ESRrotational correlation time r. On the other hand, the correlation between Tand the relative height hr of peak on high field was reverse. The results are discussed in the paper.
Crystal and Molecular Structure of BiCl
3
(15-Crown-5)
Fan Yuepeng, Zhang, Wenxing, Wei Yunhe, Lu Chengxue
1990, 6(1): 28-31.
Abstract
(
)
PDF
(276KB) (
)
Related Articles
|
Metrics
Single crystals of complex BiCl3(15-crown-5) were synthesized by gel method, and the structure was solved from X-ray diffraction data by direct and Fourier methods. The crystal is orthorhombic, space group is P2
1
2
1
2
1
with unit cell parameters:a=7.677(4), 6=13.254(6) and c=15.911(6)A , and Z=4. The final structural refinement converged with unweighted and weighted factors of 0.053 and 0.063 respectively for 1290 observed reflections. The structure consists of discrete BiCl
3
(15-crown-5) molecules in which bismuth atom is sandwiched between two essentially parallel planes, one of which contains five oxygen atoms and the other contains three chlorine atoms.
Structure and Catalytic Activity of Nickel-substituted Mica- montmorillonite Clay Crosslinked with NH
2
(C
3
H
3
)Si(OC
2
H
5
)
2
Jiang Dazhen, Cai Hui, Liu Ziyang, Zhou Qun, Min Enze, He Mingyuan
1990, 6(1): 32-40.
Abstract
(
)
PDF
(590KB) (
)
Related Articles
|
Metrics
Nickel-substituted mica-montmorillonite clays(Ni-SMM) were synthesized, the pillared clays, Si-Ni-SMM, were prepared from the Ni-SMMintercalated with NH
2
(C
3
H
5
)Si(OC
2
H
5
)
3
. The pillar perhaps consists of tripolymer of silica according to the judgement from the pillar height (8. 5A ) data. The results of IR, ESRand XRDindicate that the hydroxy group in the octahedral layer is attacked by crosslinking agent. Thus the silicon oxide pillars become directly linked via oxygen to the nickel atoms in the octahedral layer. The change of the ratio of Lewis to Bronsted acidity on Si-Ni-SMMreduced at 400℃ by H
2
shows that the hydrogenating component such as Ni in the framework of SMMplays an important role in catalyst deactivation in H, atmosphere. This kind of action may be due to spilled- over hydrogen.
Theoretical Studies on the Mechanism of Photocycloaddition Reaction Between 6-Azauracil and Acetone
Fang Decai, Fu Xiaoyuan
1990, 6(1): 41-46.
Abstract
(
)
PDF
(392KB) (
)
Related Articles
|
Metrics
The mechanism of photocycloaddition reaction between 6-azauracll and acetone was studied by using semiemptrical SCFMO AMImethod. It was found that this reaction is not a concerted one. The calculated results are as follows:(1) A T
1
state exciplex is on the T
1
state energy surface; (2) Texciplex as a reactant will proceed along the energy surface of T
1
state to form a diradical intermediate. The energy barrier of this reaction step is 63.6 kJ/mol; (3) The T
1
state diradical intermediate happens to be close in energy to the ground state intermediate with a similar geometry. Such a situation turns out to be very favorable for an intersystem crossing (jump from the T, state to the ground state); (4) The final product will be formed from the ground S
0
state intermediate via an energy barrier 88.2 kJ/mol.
Preparation of Highly Dispersed Supported Metal Catalysts via Solvated Metal Atom Impregnation (V)-The Effects of Hydroxyl Group on the Surface Concentrations of SiO
2
on the Properties of Supported Fe Clusters
Wu Shihua, Yang Shujun, Huang Weiping, Wang Xukun
1990, 6(1): 47-55.
Abstract
(
)
PDF
(730KB) (
)
Related Articles
|
Metrics
Two kinds of small iron clusters supported on SiO
2
-200 (dehydroxylated at 200℃ and SiO
2
-600 (de-hydroxylated at 600℃) were prepared by Solvated Metal Atom Impregnation (SMAI) techniques. The iron atom precursor complex, bis (toluene) iron(0) formed in the metal atom reactor, was impregnated into SiO
2
having different concentrations of surface hydroxyl groups to study the effect of surface hydroxylation on the crucial stage of iron cluster formation. Catalysts prepared in this way were characterized by THM, Mosbauer and chemisorption measurements, and the resules show that higher concentration of surface hydroxyl groups of SiO
2
-200 favours the formation of more positively charged support iron cluster Fe
2
/SiO
2
-200 and the lower concentration of surface hydroxyl groups of SiO
2
-600 favours the formation of basically neutral supported iron cluster Fe
2
/SiO
2
-600. The measured results also indicate that the higher concentration of surface hydroxyl groups causes the precursor complex,bis(toluene) fron(0), to decompose more rapidly, and favours the formation of relatively large iron cluster. As a consequence, these two kinds of catalysts show different catalytic properties in Fischer-Tropsch reaction. The catalytic pattern of Fe/SiO
2
-200 in F-Treaction is similar to that of the unreduced a-Fe
2
O
2
, while Fe
2
/SiO
2
-600 is similar to that of reduced α-Fe
2
O
2
.
Synthesis and Determination of Standard Molar Enthalpies of Formation for Complexes of Rare Earth Isothiocyanates with Glycine
Yin Jingzhi, Jiang Bengao, Yang Shurong
1990, 6(1): 56-61.
Abstract
(
)
PDF
(421KB) (
)
Related Articles
|
Metrics
Four solid complexes of rare earth isothiocyanates with glycine were synthesized. They were characterized by chemical analysis, elemental analysis, Infrared spectra, X-ray powder diffraction and TO-DSCanalysis. Their chemical formulae were proved to be RE(NCS)
2
·Gly·H
2
O, where REis La, Ce, Pr or Nd. The integral heats of solution of RE(NCS)
3
·3Gly·H
2
Oin water, of RE(NCS)
2
·7H
2
Oin aqueous glycine solution and of glycine in water have been measured calorimetricaliy at 298. 15K. By means of a thermochemical cycle suggested in this paper, the standard molar enthalpies of formation for RE(NCS)
2
·3Gly·H
2
O(c) were obtained and their lattice energies were calculated.
Cosine Moments and Their Application to ∑ Relationships
Guo Dongyao, Guo Shishan
1990, 6(1): 62-66.
Abstract
(
)
PDF
(297KB) (
)
Related Articles
|
Metrics
Recent advances In the theory of ∑ relationships lead to the Investigation of moments needed to derive the relavant joint probability densities. These together with the linear theory of relationships, make possible the calcualtion of therelationships from ∑
1
to ∑
2
one by one. The superior performance ofour new ∑
4
and ∑
r
relationships, for example, with respect to the older ∑
1
and ∑
3
formulas strongly suggests a deeper study of the pertinent moments. In this paper a new concept, the cosine moment, is introduced which, together with a certain integral theorem, permits the derivation of the relevant joint probability densities. These lead in turn to the derivation of all ∑ relationships valid for all the space groups.
Kinetic Studies on Ligand Substitution Reactions of Metallothioneins with DTPA and EDTA
Li Rongchang, Gao Fei, Wang Kui
1990, 6(1): 67-72.
Abstract
(
)
PDF
(442KB) (
)
Related Articles
|
Metrics
Cd, Zn-thionelns were isolated from the rat liver by improved Winge method and purified further. The composition was determined. The mobilization of Cd ions from the Cd, Zn-metallothioneins was studied with spectrophotometric method. The results show that the reaction of DTP Aor EDTAwith Cd, Zn-thioneins occurs through three steps. The first step follows pseudo-first order reaction with association mechanism. The formation constants and the dissociation rate constants of the relevant intermediate ternary complexes and apparent rate constants, K
app
were determined. The properties and structure of Cd, Zn-thioneins and ligands with low molecular weights affect the values of K
app
.
Syntheses of Divalent Rare Earth Ternary Halides KYbBr
3
, KYbCl
3
, KSm
2
Br
5
, KSm
2
Cl<
5
, KEu
2
Cl<
5
by Alkalimetallothermoreduction
Lin Pingdi, Wu Guoqing, LU Xiukai, Xu Bi
1990, 6(1): 73-75.
Abstract
(
)
PDF
(215KB) (
)
Related Articles
|
Metrics
Introduction CsEuF
3
, CsYbF
3
and RbYbF
3
are the first members of divalent rare earth ternary halides obtained via reduction of trivalent rare earth halides by alkali metals.
A Quantitative Study of Solvent Effects on Keto-Enol Tautomeric Equilibria
Chen Zikang, Zhang Yuejun
1990, 6(1): 76-79.
Abstract
(
)
PDF
(275KB) (
)
Related Articles
|
Metrics
Organic compounds usually have labile bonds. It is well known that thousands of reactions are carried out in solutions, only a few in the gas-phase.
Photopolymerization Initiated with Bis-[O-(α-Methacryl)]-α,β-Dioximes and Tertiary Amines
Tong Weida, Sun Meng, Yang Yuliang, Tang Lijun, Yu Tongyin
1990, 6(1): 80-84.
Abstract
(
)
PDF
(367KB) (
)
Related Articles
|
Metrics
Among sensitizing systems, the combination of benzophenone(BP) and tertiary amines(TA) has been deeply studied.
Studies on the Morphology of Natural Rubber/Polyacrylate Interpenetrating Polymer Networks
Llao Kalrong, Thomas C. Ward
1990, 6(1): 85-89.
Abstract
(
)
PDF
(920KB) (
)
Related Articles
|
Metrics
The interpenetrating polymer network(IPN) systems have attracted a lot of attention because of their unique two-phase structure and properties. There have been many publications concerning the IPNs in which poly (isoprene)(PIP) or polyacrylates (PAC) is formed as one of the networks.In the present study, Four serles of natural rubber(NR)/PAC IPNs were prepared and their morphologies were investigated with dynamic mechanics analysis(DMA) and transmission electron microscopy (TEM).
Editor-in-Chief:
Jihong YU
ISSN 1005-9040
CN 22-1183/O6
Office Online
Submit Manuscript
Peer Review
Editor Office
Special Issue/Column
more...
Download
CRCU template for Article
CRCU template for Review
Copyright transfer statement
More...
News
“ Chemical Research in Chinese Universities”紧急通知
2022-03-14
Notice: Series of forums
2020-06-11
More...
Links
Springer
Chem. J. Chinese Universities
More...
Scan and join us
Visited
Total visitors:
Visitors of today:
Now online:
