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Table of Content
24 February 2006, Volume 22 Issue 1
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Structure of Metal Aluminophosphates:Al
9-
x
M
x
P
12
O
48
(TREN)
4
·
y
NH
4
·
z
H
2
O[TREN=N(CH
2
CH
2
NH
3
)H
m
, M=Mn, Co]
XU Yao-hua, LI Yong-xiu, FENG Shou-hua, CHEN Xiao-feng, JIN Hai-ying, PANG Wen-qin, DUAN Chun-ying, YOU Xiao-zeng
2006, 22(1): 1-5.
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Two large-pore metal-doped aluminophosphates, Mn
4
Al
5
(PO
4
)
12
[N(C
2
H
4
NH
3
)
3
]
3
[N(C
2
H
4
NH
3
)
2
·(C
2
H
4
NH
2
)](NH
4
)
2
·14H
2
O(Mn
4
-NJU) and Co
4
Al
5
(PO
4
)
12
[N(C
2
H
4
NH
3
)
3
][N(C
2
H
4
NH
3
)
2
(C
2
H
4
NH
2
)]
3
·(NH
4
)
4
·13H
2
O(Co
4
-NJU), which have the same open framework structures, were hydrothermally synthesized. The structures of these compounds consist of TO
4
tetrahedra, which are linked together by corner-sharing to form an open framework with unique intersecting twelve-membered ring channels in three dimensions. The compounds crystallize in cubic space group
I
(-4)3
m
with
a
=1.6795(2) nm and
V
=4.7374(9) nm
3
for Mn
4
-NJU, and
a
=1.67372(19) nm and
V
=4.6887(9) nm
3
for Co
4
-NJU, respectively. Single crystal structure analyses show that the protruding O atoms of the frameworks of the compounds are linked to protonated 4-(2-aminoethyl)diethylenetriamine(TREN, C
6
H
18
N
4
) ions in the windows by means of hydrogen-bonding under the hydrothermal condition. It is also found that the components inside the super cages of the compounds are changeable, and the metal ions M
2+
(M=Mn, Co) and Al
3+
disorderedly occupy the same crystallographic positions.
Articles
Synthesis and Anti-inflammatory Action of(η-C
5
H
5
)
2
Ti(Sal)
2
and (η-C
5
H
5
)
2
Ti(Clo)
2
LI Xiu-juan, ZENG Zheng-zhi
2006, 22(1): 6-10.
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Two new complexes (Cp)
2
Ti(Sal)
2
and(Cp)
2
Ti(Clo)
2
(Cp=Cyclopentadienyl η
5
-C
5
H
5
), have been synthesized in anhydrous THF by the reaction of Hsal(
o
-hydroxybenzoic acid, salicylate acid) or Hclo[
N
-(
m
-chloro-phe-nyl) anthranili acid, acidum clofenamicum] with (Cp)
2
TiCl
2
and characterized by means of elemental analyses, IR,
1
H NMR,
13
C NMR, UV and molar conductivity. In complex (Cp)
2
Ti(Sal)
2
or (Cp)
2
Ti(Clo)
2
, the oxygen atom of the carboxyl group coordinates to Ti(IV) in a monodentate manner. The inhibitory action of the complexes on mouse ear tumefaction caused by croton oil and rat foot granulation growth caused by cotton balls is higher than that of the corresponding ligands Hsal, Hclo and [(Cp)
2
TiCl
2
], whereas their toxicity is lower than those of the free ligands.
Uniform Rice-like CdS Particles Prepared from Water-in-oil Microemulsions
ZHOU Hai-cheng, XU Sheng, PENG Qing, LI Ya-dong
2006, 22(1): 11-13.
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Uniform rice-like CdS particles were synthesized in cyclohexane/Triton X-100/
n
-pentanol/water quaternary microemulsions. The as-prepared samples were characterized by X-ray diffraction, transmission electron microscopy, and electron diffraction. The results indicate that the size and the shape of the rice-like CdS particles can be influenced by the molar ratio of water to the surfactant(
w
value) and the reactant concentrations.
Fluorescence and Thermostability of Nanometer Porphyrin Trimer
SHI Ying-yan, FA Huan-bao, ZHENG Wen-qi, LI Di, SHAN Ning, WANG Xing-qiao
2006, 22(1): 14-16.
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A nanometer porphyrin trimer was firstly synthesized with 1,3-dibromopropane as a bridge-linked agent and the fluorescence property and thermostability were studied. The results show that the fluorescence property and thermostability of the trimer are different from those of monoporphyrin. The effects of the molecule structure on the optical property and the thermostability were also studied in detail.
X-ray Crystal Structure and Characterization of Tetra-vanadyl Capped Highly Reduced Polyoxometalate Anion[Pmo
5
Ⅵ
Mo
7
Ⅴ
O
40
(V
Ⅳ
O)
4
]
2-
CHANG Song, QIN Chao, WANG Xin-long, LI Yang-guang, WANG En-bo
2006, 22(1): 17-20.
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)
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A novel polyoxometalate [H
3
O]
2
[Pmo
5
Ⅵ
Mo
7
Ⅴ
O
40
(V
Ⅳ
O)
4
]·6Py(Py=pyridine) was synthesized and characterized by IR spectrometry, TG and single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic space group(
C
2/
m
) with
a
=1.3680(3) nm,
b
=2.1740(4) nm,
c
=1.1630(2) nm,
β
=118.62(3)°,
V
=3.0362(10) nm
3
,
Z
=2, and
R
1
(
w
R
2
)=0.0772(0.2312). The compound contains a highly reduced vanadylpolymolybdophosphate polyoxometalate anion with a four-capped structure. The four {VO} units cap four opposite pits of the pseudo-Keggin core {PMo
12
O
40
}.
Solid Phase Extraction Chemiluminescence Determination of Methamidaphos on Vegetables
LI Xiao-zhou, GUAN Ting-ting, ZHOU Chi, YIN Ji-qiu, ZHANG Yi-hua
2006, 22(1): 21-24.
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The determination of the methamidaphos pesticide residue on vegetables with a simple solid phase extract(SPE) flow injection(FI)-chemiluminescence(CL) method is described. The method is based on the enhancing effect of methamidaphos on the CL reaction of luminol with hydrogen peroxide in an alkaline solution. Under the optimal conditions, the CL intensity is linear to the methamidaphos mass concentration in a range of 0.2-13 Lg/mL(r=0.9992). The detection limit(3R) is 0.047 Lg/mL. The relative standard deviations for the analysis of three samples are 1.8%, 2.5% and 3.7%(n=5), respectively. The recovery is in a range of 90%-109% by the method. In this work, this method was successfully applied to the determination of the methamidaphos residue on some vegetable samples.
Several Rules for Treating Phenol Wastewater via Oxidation by O
3
/UV-formed Radicals
LIU Miao, JIAO Xin-qian, WU Di, DIAO Wei-li, ZHANG Yu
2006, 22(1): 25-28.
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)
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The treatment of phenol wastewater with an ultraviolet source and an oxone generator by introducing salicylic acid as the capturer is described. The presence of HO
·
during the phenol degradation has been proved. The impacts of factors such as acidity and reaction time on the HO
·
formation are also discussed. The results demonstrate that HO
·
generated from ozone/UV oxidation under a basic condition is the immediate cause of phenol degradation. At room temperature and a pH value of 9.93, the degradation of phenol occurs rapidly within 0.5 min and the removal of phenol(100 mg/L) is above 98.5% within 15 min; in the meantime, the pH value declines gradually with the degradation of phenol. A discussion about the formation and the transformation of the intermediate products during phenol degradation is included.
Effects of Nitrobenzenes on DNA Damage in Germ Cells of Rats
XU Jing-bo, JING Ti-song, YANG Li, SUN Zhi-wei, SHI Long
2006, 22(1): 29-32.
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The single cell gel electrophoresis(SCGE) technique was used to detect DNA damage in germ cells of rats, which was induced by five tested nitroaromatic compounds. Mixed cultures of Sertoli and germ cells were prepared from the rats testis and their responses to m-dinitrobenzene(
m
-DNB), 2,4-dinitrotoluene(2,4-DNT), 2,6-dinitroto-luene(2,6-DNT), 4-nitrotoluene(4-NT) and 2,4-dinitroaniline(2,4-DNAn) were studied. The results show that all the five chemicals have a reproductive toxicity. Each dose group and the control group were significantly different(
P
<0.01). All of them can lead to the damage to DNA in the germ cells of Kunming male rats in the definite range of concentration(m-DNB: 0.04-25 μmol/L; 2,4-DNT, 2,6-DNT and 4-NT: 0.032-500 μmol/L; 2,4-DNAn: 0.8-20 μmol/L). When the concentration increases, the damage rate will become higher, which shows an evident logarithm dose-effect relationship.
Two New Butenolide Derivatives from
Erigeron acer
WU Gang, FEI Dong-qing, GAO Kun
2006, 22(1): 33-35.
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)
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Two new butenolide derivatives, named as erigeracerin A and erigeracerin B, which are a pair of epimers, were isolated from
Erigeron acer
. Their structures were elucidated by spectroscopic analysis including 2D NMR and HR-ESI-MS.
Further Investigation on the Rearrangement Mechanism of Reactions of 1,5-Benzothiazepines with Ethoxycarbonylcarbene
WU Chun-zan, HUANG Jia-xing, ZHANG Qi-han, XU Jia-xi
2006, 22(1): 36-39.
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)
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The reactions of 2,3-dihydro-1,5-benzothiazepines with ethoxycarbonylcarbene undergo complex rearrangements to produce ring-opening and ring contraction products. Previously it was presumed that the different products were formed
via
different mechanisms depending on the kind of substituents at the 2-position of 1,5-benzothiazepines. However, on the basis of the further detailed investigation, it was found that all 1,5-benzothiazepines can undergo the same rearrangement to yield both ring-opening and ring contraction products.
Characterization of 4-Aryl-5-ethoxycarbonyl-6-methyl-3,4-dihydro-pyrimidin-2(1
H
)-thiones by EI-TOF Mass Spectrometry
LI Qian-rong, XUE Song, YIN Hao
2006, 22(1): 40-44.
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)
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The electron impact(EI) time-of-flight mass spectra(TOFMS) of the title compounds(thioxo-Biginelli compounds) were studied to establish their fragmentation pathways. With a TOF instrument of high resolution, the exact mass for each fragment was determined. These data were used to infer the molecular formulas and the ionic elemental compositions for all the compounds through interpretation by software. By further applying chemical intuition, majority of the fragmentation ions were fully assigned. All the compounds give strong signals(average 76%) for their molecular ions in the EI spectra. Two kinds of characteristic fragmentation pathways from the molecular ion were observed. One is related to the loss of the ester group, forming a resonance stabilized ion with a moderate abundance(average 40%). The other concerns the loss of the aromatic-ring radical, forming another resonance stabilized ion at
m
/
z
199 with a high abundance(average 79%), from which further important fragmentations including the formation of an ion at
m
/
z
171(average 24%) by the loss of C
2
H
2
(
via
the McLafferty rearrangement), and an ion at
m
/
z
153(average 10%) by the elimination of a water molecule preceed. In addition, ion [M-Et]
+
with a high abundance(average 62%) is a characteristic for the Biginelli compounds with an ethoxycarbonyl group. Differences and similarities among the fragmentations observed from the EI-TOFMS of oxo-Biginelli compounds are discussed.
Stereoselective Syntheses and Biological Properties of (
E
)-α-(Methoxyimino)-2-[1-(aryloxy)methyl]-benzeneacetates
LI Yan, LIU Jie, ZHOU Ye-bing, ZHANG Hong-quan, CHEN Zu-xin, LIU Zhao-jie
2006, 22(1): 45-50.
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(
E
)-α-(Methoxyimino)-2-[1-(aryloxy)methyl]-benzeneacetates, the analogues of Kresoxim-methyl, were stereoselectively synthesized with the coupling reaction of 2-methylphenyldiazonium chloride and methyl 2-hydroxyiminoacetate in the presence of CuSO
4
/Na
2
SO
3
as a key step, and it was first found that the coupling reaction could give the key intermediate material(
E
)- and(
Z
)-methyl 2-(hydroxyimino)-2-
o
-tolylacetate with a molar ratio of 14∶1. The(
E
)-configurations of all these compounds were assigned on the basis of their 2D-NOESY spectra of
1
H NMR. The preliminary bioassays indicate that most of the compounds show an activity against a wide variety of fungi.
An Improved Synthetic Method of Saquinavir
YANG Qin-gang, HE Xu-chang, LEI Li-jun, ZHOU Qi-ting, BAI Dong-lu
2006, 22(1): 51-55.
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)
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An improved synthetic method of saquinavir, an HIV protease inhibitor, is described. In comparison with the methods in the reported works, the improved procedures had several advantages, such as less expensive agents, shorter reaction time, and a smaller amount of the solvent needed. To measure the optical purities of the products, the intermediates were determined by means of chiral HPLC. Some of the intermediates can also be used for the preparation of new protease inhibitors.
RP-HPLC Determination and Pharmacokinetic Comparison of Cinnamic Acid in Rat Plasma After Administration of Di-Gu-Pi Decoction and Pure Cinnamic Acid
LI Kang, BI Kai-shun
2006, 22(1): 56-60.
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)
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A sensitive, simple, and accurate method was developed for the determination and pharmacokinetic comparison of cinnamic acid in rat plasma after the administration of a Traditional Chinese Medicinal preparation, Di-Gu-Pi decoction, and pure cinnamic acid using RP-HPLC. Di-Gu-Pi was extracted with 5% aqueous sodium bicarbonate, which was followed by purification with ion exchange column chromatography. The plasma samples taken from rats were deproteinized with methanol. The reversed-phase(HPLC) system with a Diamonsil C
18
column and methanol-acetonitrile-water (8∶32∶60, volume ratio) (adjusted to pH=3.0 with glacial acetic acid) as the mobile phase was employed for the separation of cinnamic acid in the plasma samples. The detection was set at 272 nm and 3-(
p
-fluorophenyl)-2-propenoic acid was chosen as the internal standard. The calibration curve was linear in a range from 0.10 to 25.0 μg/mL (
R
2
=0.9988,
n
=9). The precision was 3.42%-10.10%; the between-day precision was 2.84%-8.91%; the accuracy was -1.51%-1.26%; the mean recovery was 99.9%. The method was found to be sensitive, simple, accurate and appropriate for the determination of cinnamic acid.
Chemical Modification and Fluorescence Spectrum of Tryptophan Residues in Pullulanase
TENG Li-rong, FAN Hao, ZHANG Yuan-yuan, YU Qi, HUANG Yue-feng, LIU Lan-ying
2006, 22(1): 61-64.
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)
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Tryptophan(Trp) residues in a pullulanase were modified by
N
-bromosuccinimide(NBS). The results of the Spande method indicate that there are 18 Trp residues in the pullulanase and nine of them are located on the surface of the enzyme. Three of these Trp residues are nonessential residues which show the fastest reaction rate according to the Zou′s plot. Two of the seven relative faster reacting residues are essential for the activity of the enzyme. The other eight are the slowest in the reaction rate or non-reactive residues for the reaction. The fluorescence and circular dichroism(CD) spectra of the pullulanase have been changed after the reaction with NBS. Potassium iodide(KI) and acrylamide also have remarkable influences on the fluorescence spectra of the pullulanase.
Peptidase Activities of Tripeptidyl Peptidase Ⅰ(TPP Ⅰ): Exopeptidase and Endopeptidase
DU Pei-ge, AN Li-ping, QIU Fang-ping, LU Gang
2006, 22(1): 65-67.
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)
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The defect of TPP Ⅰ causes a disease, late infantile neuronal ceroid lipofuscinosis(LINCL, CLN2). To investigate the bio-activity of tripeptidyl peptidase Ⅰ(TPP Ⅰ) from rat kidneys, the effects of digestion of angiotensin Ⅱ(Ang Ⅱ) and a synthetic endo-type substrate(Gly
1
-Lys-Pro-Iie-Pro
5
-Phe-Phe-Arg-Leu-Lys
10
) via TPP Ⅰ were analyzed by HPLC and TOF-MS. The data suggest that the degradation rate of Ang Ⅱ can reach 18.2% by the rat TPP Ⅰ and DRV(Asp-Arg-Val) can be released from
N
-termini of Ang Ⅱ within 16 h. In addition, the synthetic endo-type substrate is cleaved at the same position between Phe
6
and Phe
7
. Accordingly, TPP Ⅰ shows two kinds of peptidase activities. One is a tripeptidyl peptidase activity and the other is a pepstatin insensitive carboxyl endopeptidase activity. Tripeptidyl peptidase activity and pepstatin insensitive carboxyl endopeptidase activity seem to be dual phases of one enzyme, TPP Ⅰ.
PRLs Promote Spreading, Adhesion, and Proliferation of Human SW480 and SW620 Cells
LI Zhao-fa, XU Xue-song, SHEN Xing-gui, LI Qing-shan, ZHAO Zhi-zhuang, FU Xue-qi, LI Yu-lin, LI Yi-lei
2006, 22(1): 68-72.
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)
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Recent studies suggest that PRL-3 is involved in the metastasis of colorectal cancer, but the mechanism concerning that has not been well defined. This article expresses PRL-1, PRL-2, and PRL-3 and the catalytically inactive mutant forms of those enzymes in SW620 and SW480 cells, two human cell lines derived from non-metastatic cancer and metastatic colorectal cancer, respectively. While the expression of the native forms of PRLs promotes the spreading, adhesion, and proliferation of these cells, the expression of their mutant forms inhibits the earlier-mentioned processes. These data thus provide a cellular mechanism for the role of PRL-3 in tumor metastasis and suggest that all the three PRLs have similar functions.
Studies on Electrochemical Property of LiFePO
4
/C as Cathode Material for Lithium Ion Batteries
HUANG Xiao-wen, SHI Peng-fei
2006, 22(1): 73-75.
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)
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LiFePO
4
/C samples were prepared at different temperatures by adding sugar to the synthetic precursor. The samples were characterized by X-ray diffraction(XRD). Their crystal phases show an olivine structure. Only the sample obtained at 700 ℃ has a larger discharge capacity, which has good electrochemical properties: its discharge specific capacity is 120.3 mAh/g at a current of 0.05 mA, and its capacity fade is very low after 20 cycles. It is demonstrated that the best synthetic temperature should be 700 ℃.
A Simple Approach to Fabricate CdS-SiO
2
Hybrid Microspheres by Producing CdS Nanoparticles on the Surface of Thiolated SiO
2
Microspheres
HAN Kun, XIANG Zheng, WANG Zheng, WANG Chun-lei, LI Min-jie, ZHANG Jun-hu, YANG Bai
2006, 22(1): 76-79.
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)
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We have developed a simple synthetic method to prepare the hybrid microspheres of CdS nanoparticles on the surface of silica microspheres modified by(3-mercaptopropyl)trimethoxysilane(MPS). The-SH groups of MPS can bind with the Cd
2+
ions on the surface of SiO
2
. When thioacetamide releases H
2
S, the nanosized CdS particles(1-6 nm) will successfully be generated on the silica surface under the experimental conditions. The size of the CdS na-noparticles was found to be related to the concentration of Cd
2+
feed and the size of silica spheres, the higher the concentration of Cd
2+
and the larger of silica microspheres, the bigger the size of CdS nanoparticles. Techniques including UV, PL, TEM and XPS were used to characterize the CdS-SiO
2
hybrid microspheres.
Molecular Dynamics Simulation Studies on the Cooling Process of Polyvinyl Chloride
YANG Hua, LI Ze-sheng, YANG Yong-biao, ZHANG Xiu-bin, SUN Chia-chung
2006, 22(1): 80-84.
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)
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By means of molecular dynamics simulation, the transition of the conformations of polyvinyl chloride during a cooling process from 600 to 300 K was studied. The results show that the amorphous polyvinyl chloride chain experiences the melting state, elastic state and glass state and the conformations can be characterized by the increases of the
trans
-state of C-C-C-C and the near
gauche
-state of C-C-C-Cl with the decrease of temperature. It is found that the transition of the conformations is driven mainly by the Coulomb interaction between chain segments.
Effect of TiO
2
Nanoparticles on Photochromism of WO
3
Colloids
FEI Xiao-fang, SHAN Gui-ye, KONG Xiang-gui, WANG Xin, ZENG Qing-hui, ZHANG You-lin
2006, 22(1): 85-89.
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)
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WO
3
and TiO
2
colloids were synthesized by the hydrolysis technique and part of the TiO
2
colloid was treated by means of the hydrothermal method. The photochromic performances of the resulting materials obtained via combining the WO
3
colloid with the treated TiO
2
colloid and the non-treated TiO
2
colloid, respectively, are very different. The TiO
2
colloid without hydrothermal treatment can effectively improve the photochromic performance of the WO
3
colloid. The TiO
2
nanoparticles were investigated in detail by XRD, TEM, surface photovoltage spectra(SPS) and field-induced surface photovoltage spectrometry(FISPS). The photochromism mechanism of WO
3
colloid is discussed.
Investigation on Vibrational Spectra and Structures of 4-Mercaptopyridine Monomer and Its Dihydrate
CHENG Jian-bo, XUE Wei-qing, ZHAO Bing, ZHANG Gang, GONG Bao-an
2006, 22(1): 90-93.
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)
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The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory(DFT),
viz
. B3LYP method with the 6-311++G(
d,p
) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the dihydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed
via
the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be consi-derably affected by the water molecules.
A Computational Study on Water-assisted Ammonolysis of
N
-Methyl β-Sultam
HE Mao-xia, FENG Da-cheng, YU Ling-juan, CAI Zheng-ting
2006, 22(1): 94-98.
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)
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The ring opening of β-sultam
via
an H
2
O-assisted ammonolysis process was studied by using Density Functional Theory(DFT) method at the B3LYP/6-31G
*
level as a further step in the theoretical investigation of the ammonolysis reaction of β-sultams. The calculated pathways are analogous to those previously described for the non-assisted ammonolysis reaction. Solvent effects were assessed by using the polarized continuum model(PCM) method. The results show that mode 1 and pathway a in channel Ⅱ are the most favorable ones in both the cases. The energy barrier of the cleavage of C-S bonds producing P1 is the highest among all the energy barriers. The presence of a solvent in the continuum model disfavors the reaction, whereas the participation of water in the ammonolysis reaction plays a positive role and reduces the active energy greatly. The relative energies of all the transition states in the assisted ammonolysis are 20-80 kJ/mol lower than those for the non-assisted reaction.
Copper Promoted Au/ZnO-CuO Catalysts for Low Temperature Water-gas Shift Reaction
LAN Hong-lei, JIA Ming-jun, PAN Wei-cheng, ZHANG Wen-xiang, JIANG Da-zhen
2006, 22(1): 99-102.
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Various copper promoted Au/ZnO-CuO catalysts with different atomic ratios of Cu to Zn prepared by means of co-precipitation were tested for the low temperature water-gas shift(WGS) reaction. The catalytic activity of the catalyst depends largely on the ratio of Cu to Zn. The addition of an appropriate amount of copper can considerably improve both the catalytic activity and the stability of the catalyst in comparison with those of copper-free Au/ZnO catalysts. The enhanced reducibility of copper oxide in the Au/ZnO-CuO ternary-component catalysts, which was confirmed by H
2
-TPR, may be related to the high activity and stability of the catalyst for the low temperature WGS reaction.
Influences of Temperature and Coal Particle Size on the Flash Pyrolysis of Coal in a Fast-entrained Bed
CUI Li-jie, LIN Wei-gang, YAO Jian-zhong
2006, 22(1): 103-110.
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)
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The experiments on the flash pyrolysis of a lignite were carried out in a fast-entrained bed reactor as a basic study on a so-called 'coal topping process'. The investigation focused on the effects of pyrolysis temperature and coal particle size on the product distribution and composition. The experimental results show that an increase in the pyrolysis temperature results in a higher yield of gaseous products while a larger particle size leads to a decrease of the liquid yield. An optimum temperature for the liquid yield was found to be 650 ℃. A certain amount of phenol groups was found in the liquid products, which may be used to produce high-valued fine chemicals. The FTIR analyses of the coal and chars show that aliphatic structures in the chars are gradually replaced by aromatic structures with the increasing of pyrolysis temperature and coal particle size. The results of this study provide fundamental data and optimal conditions to maximize light oils yields for the coal topping process.
Thermodynamics of Solvent Extraction of Rare and Scattered Metal-Indium with Diethylhexylmonothiophosphoric Acid
LIU Xing-zhi, ZANG Shu-liang, FANG Da-wei, LI Jun, WANG Lu-ning
2006, 22(1): 111-113.
Abstract
(
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The thermodynamics of extracting In(Ⅲ) with diethylhexylmonothiophosphoric acid as an extractant in a H
2
SO
4
system is reported. The equilibrium molalities of In
3+
ions were measured at a high acidity and ionic strengths varying from 0.1 to 2.0 mol/kg in an aqueous phase containing Na
2
SO
4
as the supporting electrolyte. The values of the standard extraction constant
K
0
at various temperatures were obtained by the methods of extrapolation and polynomial approximation. The equation lg
K
0
=-31.93-5.93×10
3
/
T
+6.15×10
-2
T
was also obtained and the thermodynamic quantities for the extraction process were calculated.
Synthesis and Properties of Poly(aryl ether ketone) Copolymers Containing 2,7-Naphthalene Moieties
LIU Si-jie, NIU Ya-ming, ZHU Xiao-liang, WANG Gui-bin, JIANG Zhen-hua
2006, 22(1): 114-117.
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Poly(aryl ether ketone) copolymers containing 2,7-naphthylene and hydroquinone(HQ) moieties with various compositions were prepared by the reaction of 4,4′-difluorobenzophenone(DFB) 2,7-naphthylene and hydroquinone in the presence of sodium carbonate and potassium carbonate(19∶1, mass ratio) in diphenyl sulfone(DPS). The thermal analysis results of the copolymers show that the glass transition temperatures(
T
g
s) increase, while the melting temperatures(
T
m
) and the 5.0% weight loss temperatures(
T
d
) decrease with the increase of the 2,7-naphthalene moieties. For the copolymers synthesized at a molar fraction of 2,7-naphthalene in the difluoro monomers being over 0.30, no peaks corresponding to the cold crystallization temperature and the melting temperature could be detected, indicating that these copolymers are almost amorphous. The crystal structures of the copolymers with a molar fraction of 2,7-naphthalene being less than 0.30 are rhombic.
Cure Kinetics of DGEBA with Hyperbranched Poly(3-hydroxyphenyl) Phosphate as Curing Agent Studied by Non-isothermal DSC
YAO Liang, DENG Jing, QU Bao-jun, SHI Wen-fang
2006, 22(1): 118-122.
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The cure kinetics of diglycidyl ether of bisphenol A(DGEBA) with hyperbranched poly(3-hydroxyphenyl) phosphate(HHPP) as the curing agent was investigated by means of non-isothermal differential scanning calorimetry(DSC) at various heating rates. The results were compared with the corresponding results by using 1,3-dihydroxybenzene(DHB) as a model compound. The results show that HHPP can enhance the cure reaction of DGEBA, resulting in the decrease of the peak temperature of the curing curve as well as the decrease of the activation energy because of the flexible -P-O- groups in the backbone of HHPP. However, both the activation energy of the cured polymer and the peak temperature of the curing curve are increased with DHB as a curing agent. The cure kinetics of the DGEBA/HHPP system was calculated by using the isoconversional method given by Málek. It was found that the two-parameter autocatalytic model(Šesták-Berggren equation) is the most adequate one to describe the cure kinetics of the studied system at various heating rates. The obtained non-isothermal DSC curves from the experimental data show the results being accordant with those theoretically calculated.
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