Loading...
Toggle navigation
CJCU
Home
About Journal
Editorial Board
Editorial Board
Youth Executive Editorial Board
Editorial Introduction
Guide for Author
Journal
Forthcoming Articles
Asap
Current Issue
Archive
Most Download Articles
Most Read Articles
Most Cited Articles
Email Alert
RSS
Subscription
Contact Us
中文
Table of Content
24 August 2004, Volume 25 Issue 8
Previous Issue
Next Issue
Articles
Synthesis,Characterization and Intercalation Behavior of γ-Zirconium Benzylphosphonate-phosphates
HUANG Kun-Lin, YU Ji-Hong, ZOU Yong-Cun, LI Cai-Jin, WANG Guang-Mei, DING Hong, JIN Wei-Jie, XU Ru-Ren
2004, 25(8): 1387-1390.
Asbtract
(
)
PDF
(582KB) (
)
References
|
Related Articles
|
Metrics
γ-ZrP with a high crystallinity was prepared at 220 ℃. Three γ -zirconium benzylphosphonate-phosphates,formulated as Zr(PO
4
)(H
2
PO
4
)
0.15
(C
6
H
5
CH
2
PO
3
H)
0.85
·0.4H
2
O(1,
d
=1.86 nm), Zr(PO
4
) (H
2
PO
4
)
0.30
(C
6
H
5
CH
2
PO
3
H)
0.70
·0.6H
2
O(2,
d
=1.78 nm) and Zr(PO
4
)(H
2
PO
4
)
0.50
·(C
6
H
5
CH
2
PO
3
H)
0.50
·0.7H
2
O(3,
d
=1.66 nm),were synthesized and characterized by means of
31
P MAS NMR,XRD and TG method. The intercalation behavior of the new compounds with α -phenylethylamines are investigated.
Solvothermal Synthesis and Characterization of K
4
Ag
2
Sn
3
S
9
·2H
2
O with Layer Structure
BAIYIN Meng-He, JI Min, LIU Xin, AN Yong-Lin, JIA Cui-Ying, NING Gui-Ling
2004, 25(8): 1391-1394.
Asbtract
(
)
PDF
(755KB) (
)
References
|
Related Articles
|
Metrics
A novel compound K
4
Ag
2
Sn
3
S
9
·2H
2
O with a layer structure was synthesized by a mild solvothermal route. The compound was characterized by X-ray diffraction,IR and UV-Vis diffusion reflectance spectrometry and DSC-TG techniques. The compound crystallizes in a monoclinic space group
P
2
1
/
m
with
a
=0.780 71(2) nm,
b
=2.735 08(1) nm,
c
=1.050 08(2) nm, β =103.874(1),
V
=2.176 82(1) nm
3
,
Z
=4. This compound comprises of hollow layers built from adamantane-like anionic clusters [AgSn
3
S
9
]
5-
. Potassium ions and water molecules locate between the layers. The DSC-TG data show that this compound hydrolyzes partially during dehydration,and collapses at 450 ℃ in nitrogen. UV-Vis diffusion reflectance spectrum suggests that the title compound is a semiconductor with an estimated band gap of 2.4 eV.
Synthesis,Molecular Structure and Spectral Properties of η
6
-(Acenaphthylene) Chromium Tricarbonyl Complex
LUO Xi-Li, TIAN Xiao-Hui, LI Chen-Yan, LIN Jia-Ping, CHEN Tao, XU Shi-Ai
2004, 25(8): 1395-1399.
Asbtract
(
)
PDF
(1604KB) (
)
References
|
Related Articles
|
Metrics
η6-(Acenaphthylene)chromium tricarbonyl complex was obtained as a racemic mixture of two enantiomers by treating the free ligand with (NH
3
)
3
Cr(CO)
3
in refluxing tetrahydrofuran and characterized by IR,
1
H NMR,
13
C NMR,MS and elemental analysis. Purple-black crystals of C
12
H
8
Cr(CO)
3
form in the
P
2
1
/
c
space group with
Z
=4,
a
=0.871 9(7) nm,
b
=1.243 6(10) nm,
c
=1.150 4(9) nm, β =111.835(13)°. The full structure was determined by X-ray single crystal diffraction and the result indicated that chromium is η 6-coordinated to one six-membered ring of acenaphthylene. Face to face stack of coordinated aromatic rings by Cr(CO)
3
group on the outside is clearly observed between the two enantiomers possibly originated in the course of IRHRs (Inter-ring hatotropic rearrangements). Photophysical properties comparisons of the complex and the free ligand were also studied in advance.
Long Phosphorescence Persistence Property of Cd
2
Ge
7
O
16
:Pb
2+
YI Shou-Jun, LIU Ying-Liang, ZHANG Jing-Xian, YUAN Ding-Sheng
2004, 25(8): 1400-1402.
Asbtract
(
)
PDF
(405KB) (
)
References
|
Related Articles
|
Metrics
Cd2Ge 7O16 :Pb
2+
was prepared by the high temperature solid state method. The material is a single phase. From the emission spectra and excitation spectra of Cd
2
Ge
7
O
16
:Pb
2+
and Cd 2Ge 7O 16,it can be seen that the luminescence of Cd
2
Ge
7
O
16
:Pb
2+
is due to the 3 P 1- 1 S 0 transitions of Pb
2+
ions, the peak at 497 nm of Cd
2
Ge
7
O
16
:Pb
2+
doped with 2%Pb
2+
in molar fraction is the best, and the host Cd
2
Ge
7
O
16
can transfer energy to Pb
2+
. Long afterglow property of Cd
2
Ge
7
O
16
:Pb
2+
is due to the hole trap of Cd
2
Ge
7
O
16
:Pb
2+
and the hole trap can trap hole,so afterglow luminescence appears. A mode of afterglow mechanism was proposed.
Control Synthesis of Aragonite Calcium Carbonate with Glucan as the Template
YANG Lin, DING Wei-Jia, AN Ying-Ge, JIANG Kai, ZHANG Xiu-Ying
2004, 25(8): 1403-1406.
Asbtract
(
)
PDF
(1140KB) (
)
References
|
Related Articles
|
Metrics
Based on the basic principles of biomineralization,a novel aragonite calcium carbonate( CaCO
3
) compound material with a specific morphology was synthesized by biomimetic method under dynamic conditions. In our experiments, the glucan was used as the template. The obtained composite CaCO
3
were characterized by using X-ray powder diffraction(XRD) analysis and scanning electron microscopy(SEM). Furthermore,according to the results of Fourier transform infrared spectroscopy(FTIR) and measurement of conductivity,the possible mechanism of supermolecule interaction between glucan and CaCO
3
during the CaCO
3
formation process was discussed.
Preparation of Low-dimensional Nickel Sulfide Nanocrystals via Microemulsion-assisted Hydrothermal Method
CHEN De-Liang, GAO Lian
2004, 25(8): 1407-1412.
Asbtract
(
)
PDF
(831KB) (
)
References
|
Related Articles
|
Metrics
Nickel sulfide nanocrystals with novel morphologies of two-dimensional nanosheets and one-dimensional nanoneedles or nanotubes were successfully prepared in the CTAB/ n -pentanol/ n -hexane/water microemulsion under hydrothermal conditions at 130 ℃. XRD,TEM,SAED and TG-DSC were used to characterize the as-synthesized samples. TEM images show that nickel sulfide nanosheets with a small thickness(less than 10 nm) and nanoneedles with a hollow center(or nanotubes), ca . 50—150 nm in diameter and several microns in length,can be obtained by hydrothermally treating for 5 h and 15 h,respectively. XRD patterns show that the major phase of the nanosheets is hexagonal NiS
1.03
,and that the nanoneedles are the mixture of hexagonal NiS
1.03
and a small amount of millerite NiS. The sulfuration reaction and the low-dimensional nanocrystal growth mechanism have been discussed in detail. The result reveals that the nanosheets firstly formed under the soft template action of the W/O microemulsion,and then the resulted nanosheets rolled up into one-dimensional nanoneedles or nanotubes.
Fabrication of ZrO
2
Nanofibers by Electrospinning
GUAN Hong-Yu, SHAO Chang-Lu, LIU Yi-Chun, HAN Dong-Xue, YANG Xing-Hua, YU Na
2004, 25(8): 1413-1415.
Asbtract
(
)
PDF
(524KB) (
)
References
|
Related Articles
|
Metrics
Thin PVA/zirconium oxychloride composite fibers were prepared by using sol-gel processing and electrospinning technique. After calcining the above precursor fibers,ZrO
2
nanofibers with a diameter of 70—100 nm were successfully obtained. The ZrO
2
nanofibers were characterized by XRD,TG-DTA,FTIR,and SEM,respectively. The results show that the crystallinity and morphology of ZrO
2
fibers are largely influenced by the calcination temperature.
Preparation and Characterization of the Y
2
O
3
:Eu
3+
Nanowires
ZHANG Ji-Lin, HONG Guang-Yan
2004, 25(8): 1416-1418.
Asbtract
(
)
PDF
(605KB) (
)
References
|
Related Articles
|
Metrics
The nanowires of Y
2
O
3
:Eu
3+
phosphor were synthesized by using AAO template method. By the observation of the SEM images,the characteristics of morphologies between Y
2
O
3
:Eu
3+
nanowires and Al
2
O
3
nanowires produced by etching the empty AAO template was compared. The results of the SEM image analysis indicate that each nanowire is composed of a lot of agglutinating nanoparticles. At the same time,the Y
2
O
3
:Eu
3+
nanowires were confirmed by EDX and PL spectra. The results of the XRD and SAED show that Y
2
O
3
:Eu
3+
nanowires are mainly composed of polycrystalline materials with a cubic phase.
Hydrothermal Synthesis and Crystal Structure of a 3D Rare-earth Coordination Polymer [Ce
2
(H
2
btc)(btc)(H
2
O)
2
]
n
FAN Hai-Lin, CAO Min-Hua, QI Yan-Juan, MAO Li, HU Chang-Wen, WANG En-Bo
2004, 25(8): 1419-1421.
Asbtract
(
)
PDF
(1187KB) (
)
References
|
Related Articles
|
Metrics
A new 3D rare-earth coordination polymer[Ce
2
(H
2
btc)(btc)(H
2
O)
2
]
n
(1) was hydrothermally synthesized and its structure was characterized by the single crystal X-ray diffraction. Compound 1 crystallizes in a triclinic crystal system,space group P 1 with
a
=0.641 17(13) nm,
b
= 0.939 41(19) nm,
c
=0.957 97(19) nm, α =103.888(17)°, β =74.57(3)°, γ =76.71(3)°,
V
= 0.540 98(19) nm
3
,
Z
=1,
R
= 0.026 4,
wR
2
=0.077 9. The three-dimensional compound 1 is built by linking one crystallographically independent nine-coordination Ce(Ⅲ) subunit through the btc and the H
2
btc ligands. Each nine-coordinate Ce(Ⅲ) unit is a distorted tricapped trigonal prism,of which eight oxygen atoms belong to six different carboxylate groups of btc or H
2
btc and a water molecule,with the Ce(Ⅲ)—O bond lengths ranging from 0.240 3(3) nm to 0.263 6(3) nm.
A Special Layer Crystal Structure of Supera-molecule Fabricated by Aromatic Iodine-Cu(Ⅱ) Coordination Polymer
ZHANG Feng, ZHANG Yang-Yang, GAO Xu, ZHANG Xiang-Dong, LI Yi-Zhi, CHEN Hui-Lan, LIU Qi-Tao
2004, 25(8): 1422-1424.
Asbtract
(
)
PDF
(525KB) (
)
References
|
Related Articles
|
Metrics
Copper(Ⅱ)-ferron(7-iodo-8-hydroxyquinoline-5-sulfonate) one-dimensional coordination polymer Na
2n
[Cu(Ferron)
2
]
n
·6 n H
2
O was synthesized and investigated by X-ray diffraction method. The polymer exhibits a linear structure by the bis-iodine-axial coordination to the octahedral Cu(Ⅱ) center,which is stabilized by the iodine-aromatic ring(edge and face) and iodine-iodine interactions between the polymer lines,forming a special layer structure. The complex belongs to a triclinic system,space group P 1,
a
=0.648 4(19) nm,
b
=0.654 5(19) nm,
c
=1.911(6) nm, α=85.42(5)°,β=85.78(5)°,γ=72.99(4)°,
V
=0.772(4) nm
3
and
Z
=1 .
Synthesis and Crystal Structure of 3D Inorganic-organic Hybrid Framework Microporous Compound Mn
3
(BTC)
2
(DMF)
4
FANG Qian-Rong, ZHU Guang-Shan, XIN Ming-Hong, XUE Ming, ZHANG Zhi-Jie, JI Chang-Zheng, SHI Xin, WU Gang, TIAN Ge, QIU Shi-Lun
2004, 25(8): 1425-1427.
Asbtract
(
)
PDF
(494KB) (
)
References
|
Related Articles
|
Metrics
The title compound Mn
3
(BTC)
2
(DMF)
4
(BTC=1,3,5-benzenetricarboxylic acid,DMF=dimethyl formamide) was synthesized under the mild conditions and its crystal structure was determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic system and belongs to space group
P
2
1
/
c
with
a
=1.787 6(4) nm,
b
=1.179 7(2) nm,
c
=1.884 8(4) nm, β =116.35(3)°,
V
= 3.561 9(12) nm
3
,
Z
=4,
D
c
=7.413 Mg/m
3
,
M
r
=871.43, μ =5.081 mm
-1
, F (000)=8 082,
R
= 0.045 6,
wR
=0.106 3. Its structure reveals that each asymmetric unit of the title polymer contains three Mn(Ⅱ) ions,six BTC and four DMF ligands. The coordination of BTC ligands with Mn(Ⅱ) ions forms a 3D infinite framework having helical chains composed with 2
1
axes and about 0.6 nm× 0.8 nm channels along the [100] direction.
Integrated Microfluidic Chip System with Gravity Driven Multiphase Laminar Flow Separation and Ion Selective Electrode Detection
CHEN Hong, FANG Qun, YIN Xue-Feng, FANG Zhao-Lun
2004, 25(8): 1428-1431.
Asbtract
(
)
PDF
(605KB) (
)
References
|
Related Articles
|
Metrics
A microfluidic chip based on multiphase laminar flow separation coupled to ion selective electrode detection was developed for the first time. The system was applied to the determination of potassium in serum,employing a multiphase laminar flow approach for separation of potassium ions from the serum matrix by diffusion into a buffer acceptor stream. Both sample and acceptor streams were driven by gravity,and potassium was determined by using an ion selective electrode integrated on the chip.
Application of Comprehensive Two-dimensional Gas Chromatography/ Time-of-flight Mass Spectrometry to Analysis of Zedoary Volatile Oil
WU Jian-Fang, LU Xin, TANG Wan-Ying, LIAN Xiao-Hong, KONG Hong-Wei, RUAN Chun-Hai, XU Guo-Wang
2004, 25(8): 1432-1437.
Asbtract
(
)
PDF
(720KB) (
)
References
|
Related Articles
|
Metrics
After optimizing the chromatographic conditions including column system,temperature program and modulation parameters,an analytical method of zedoary volatile oil was established based on comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry(GC×GC/TOFMS). The analysis of the individual components and groups were achieved. Under the optimized conditions the components of zedoary volatile oil from Guangxi province,China were identified by GC×GC/TOFMS. Among 249 components with similarities over 800,there are 18 terpenes,34 oxygenated terpenes,35 sesquiterpenes and 37 oxygenated sesquiterpenes. Sixty-nine of these components have the individual volume fractions of over 0.02%.
Prediction of Properties of Chiral Compounds by Extending Am Index
ZHANG Qing-You, QI Yu-Hua, WANG Jun, DONG Lin, XU Lu
2004, 25(8): 1438-1441.
Asbtract
(
)
PDF
(950KB) (
)
References
|
Related Articles
|
Metrics
Generally,the molecular topological indices for QSAR represent only the topological characterization of a compound. So they can′t be used to distinguish chiral or enantiomeric isomers associated with 3D geometry. In this article,chiral topological index was obtained by extending Am index devised by our laboratory. The novel indexes have been implemented in QSAR studies of a set of N -alkylated 3-(3-hydroxyphenyl) piperidines with different pharmacological activities between pairs of enantiomers. The better QSAR models can be obtained by the chiral index than those by conventional descriptors.
High Throughput Sample Introduction System for Microfluidic Chips
FANG Qun, DU Wen-Bin, HE Qiao-Hong, FANG Zhao-Lun
2004, 25(8): 1442-1444.
Asbtract
(
)
PDF
(179KB) (
)
References
|
Related Articles
|
Metrics
A high-throughput sample introduction system for chip-based microfluidic analysis was developed. The sampling system was composed of a capillary sampling probe attached to the microchip channel and an array of horizontally positioned micro-sample vials with slits fabricated on the bottom of each vial for pass-through of the sampling probe. The micro-sample vials array was fixed on a homebuilt platform capable of moving linearly under computer control. Sample introduction was performed by linearly moving the array of vials,allowing the probe inlet to sequentially enter the solutions in the vials through the slits. The use of a slotted vial array in the sample introduction system allowed convenient and rapid sample change with low sample volume in 10
-9
L range and high sampling frequency without requiring mechanical valves and pumps. The system was applied to achieve continuously automated sample change in a chip-based flow injection analysis system with absorption detection by using a liquid-core waveguide capillary flow-cell. High sampling throughput of 600 h
-1
was obtained in this system with a sample consumption of only 4.3 nL for each cycle.
Preparation of Polyacrylate-like Capillary Monolithic-column and Its Application to p-CEC
YANG Jun-Jiao, ZHANG Kai 4, GAO Ru-Yu 4, ZNANG Yu-Kui, YAN Chao,
2004, 25(8): 1445-1447.
Asbtract
(
)
PDF
(504KB) (
)
References
|
Related Articles
|
Metrics
A novel monolithic stationary phase with long alkyl chain ligands was introduced and evaluated in pressurized capillary electrochromatography(p-CEC) by using a mixture of neutral and charged compounds. The capillary monolithic-column was prepared by in situ copolymerization of ethylene dimethacrylate,alkyl alcohol and 2-acrylamido-2-methyl-1-propanesulfonic acid in a quadruple porogenic solvent consisting of 1,4-butanediol/cyclohexanol/docecanol/water. Effects of experimental parameters in p-CEC,such as pressure and electrical field strength,on the separation were investigated. The baseline separation of the components in the mixture was achieved. The monolithic column can be used as an alternative to the conventional capillary column such as the reversed phase ODS.
Determination of Serum Albumin Using Bromocresol Purple as Electrochemical Probe
WANG Xue-Liang, SUN Wei, JIAO Kui, ZHANG Kui-Tang
2004, 25(8): 1448-1450.
Asbtract
(
)
PDF
(431KB) (
)
References
|
Related Articles
|
Metrics
An electrochemical quantitative method of protein is developed based on the interaction between bromocresol purple(BP) and proteins. In pH 4.5 Britton-Robinson(B-R) buffer solution,BP has a sensitive reductive peak at -0.518 V( vs. SCE) on the hanging mercury drop electrode. After adding human serum albumin(HSA) to the above solution,the reduction peak current of BP decreased apparently without the shift of the peak potential. The decrease of the reductive peak current of BP is proportional to HSA concentration in the range of 1.0—20.0 mg/L and 20.0—200.0 mg/L with the regression equation Δ
I
″
p
=90.87+150.53 c(r =0.997) and Δ
I
″
p
=3 063.70+9.05 c(r =0.992),respectively. The binding ratio of HSA with BP is 1:2 and the binding constant β
s
=1.32×10
9
. The proposed method was applied to determine the content of HSA in blood samples and the results are in accordance with the traditional Coomassie Brilliant Blue G-250 spectrophotometric assay. This method was further applied to the determination of bovine serum albumin,bovine hemoglobin,egg albumin etc. with satisfactory results.
Construction and Performance of Two-dimensional Separation Platform of Coupling Capillary Isoelectric Focusing-zone Electrophoresis for Proteins
LIU He-Chun, YANG Chun, ZHANG Wei-Bing, ZHANG Yu-Kui
2004, 25(8): 1451-1453.
Asbtract
(
)
PDF
(566KB) (
)
References
|
Related Articles
|
Metrics
A two-dimensional separation platform of capillary isoelectric focusing(CIEF)-capillary zone electrophoresis(CZE) for proteins was constructed by a microdialysis hollow fiber interface. The interface provided ease of fabrication,speed of mass delivering and convenience of column switching. Chrome c was selected to demonstrate the 2D separation systems feasibility and resolving performance. The 2D separation system was found to greatly increase the resolving power and overall peak capacity over those obtained for either dimension alone.
In Vitro Studies of the Immunoadsorbent for Removal of IgA in IgA-nephropathy (Ⅲ)
CHU Jia-Qiang, ZHANG Wei-Hua, YU Yao-Ting, ZHU Bo-Ru, CHEN Chang-Zhi
2004, 25(8): 1454-1457.
Asbtract
(
)
PDF
(212KB) (
)
References
|
Related Articles
|
Metrics
IgA nephropathy is a kidney disorder caused by deposits of IgA inside the glomeruli of the kidney. This chronic disease may progress over a period of 10 to 20 years and usually cannot be cured effectively. Immunoadsorbent can remove the excess IgA by hemoperfusion. We prepared the adsorbent by reacting agarose with epoxy chloropropane to introduce the active epoxy group. Then it was reacted with ammonium hydroxide and glutaraldehyde to introduce a spacer and sheep anti-human IgA antibody was linked to the spacer as a ligand. In vitro experiments showed that the adsorbent thus prepared could remove excess IgA in plasma effectively and the adsorption capacity reached 74%.
Synthesis of N-(Benzothiazol-2-yl-aminodialkyl)-thiophosphate
SHI Bo-Jie, CHEN Ru-Yu, HUANG You
2004, 25(8): 1458-1460.
Asbtract
(
)
PDF
(520KB) (
)
References
|
Related Articles
|
Metrics
In order to search for highly active anticancer agent,a new type of aminodialkylthiophosphates containing a benzothiazole group was synthesized by two-step reactions. All products were characterized by
1
H NMR,
31
P-NMR and elemental analyses. The results of bioassay show that compounds 2a,2b,2c and 2d have some inhibitory effect against humanlaryngocarcinoma(squamous).
Synthesis of 4-Methyl-pyrrolo[2,1,5-cd]indolizines
LI Bin, PAN Guo-Jun, HE Ting, HU Hong-Wen
2004, 25(8): 1461-1464.
Asbtract
(
)
PDF
(199KB) (
)
References
|
Related Articles
|
Metrics
Pyrrolo[2,1,5-cd]indolizine is the most interesting member of bicyclo[3.2.2]azine. Its derivatives have received considerable attention in the field of synthetic organic chemistry due to their novel structure and properties,increasing biological interest and because their partially saturated frameworks occur in natural products. Over recent years the [8+2] cycloaddition of indolizine with an electron-deficient acetylene has been frequently employed for this purpose. In this paper we reported the synthesis of 5-methyl-pyrrolo[2,1,5-cd]indolizines starting from α -ethyl pyridine,which was converted at first to 3-acyl-5-ethyl indolizines by 1,3-dipolar cycloaddition of the corresponding pyridinium ylide with electron-deficient olefines and then the indolizines were transformed to pyrrolo[2,1,5-cd] indolizines by intramolecular condensation between the 3-acyl and the 5-ethyl groups.
Hemperfusion Adsorbents Used in the Removing of Endotoxin
YU Mei, WANG Hui-Yan, LIU Tao, YUAN Zhi
2004, 25(8): 1465-1467.
Asbtract
(
)
PDF
(449KB) (
)
References
|
Related Articles
|
Metrics
A series of modified poly(methyl methacrylate) adsorbents were prepared and their adsorption abilities to endotoxin,which is a component of the outer membrance of Gram-negative bacteria,were compared. The results showed that the adsorbent modified by dimethylamine ligand with a long spacer had the best capacity for adsorbing endotoxin. The adsorbent P-N4,having a hydroxyl group at β -site of the ligand,could form the hydrogen bond with phosphate group. The electrostatic interaction,hydrogen bond and cooperative effect of octatomic ring worked simultaneously. All these factors are responsible for the strong interactions between endotoxin molecule and the adsorbent.
Synthesis,Structure and Characterization of a Novel Six-membered Diazacyclic Compound
CHEN Xu-Fang, CHENG Cai, ZHANG Qi, ZHAO Bin, CHENG Peng, LIAO Dai-Zheng, YAN Shi-Ping, JIANG Zong-Hui
2004, 25(8): 1468-1470.
Asbtract
(
)
PDF
(266KB) (
)
References
|
Related Articles
|
Metrics
A new six-membered heterocyclic compound including four nitrogen atoms was obtained. The compound [NH
3
(CH
2
)
2
NH(CH
2
CH
2
)
2
NH(CH
2
)
2
NH
3
]·(ClO
4
)
4
·4H
2
O was characterized by X-ray single crystal diffraction,elemental analysis,IR,
1
H NMR and MS. It belongs to a monoclinic system,
P
2
1
/
n
,with
a
=0.787 34(7) nm,
b
=1.966 98(18) nm,
c
=0.820 75(8) nm, β =103.396(2)° and
Z
= 2. The molecular structure consists of six-membered heterocyclic NH
3
(CH
2
)
2
NH(CH
2
CH
2
)
2
NH(CH
2
)
2
NH
3
,ClO
4
-
and H
2
O. The six-membered heterocyclic is a stable chair conformation. Various hydrogen bonds are formed among nitrogen atoms,ClO
4
-
anion and water molecules. This compound may be a better heterocyclic ligand containing four nitrogon atoms,which can perhaps be employed to aggregate with transitional metal atoms and generate new complexes.
Michael Addition Reaction of Thiophenol with Intramolecular Hydrogen Bond in Aqueous Medium
GAO Zhao-Bo, QIU Xue-Peng, GUO Hai-Quan, KANG Chuan-Qing, GAO Lian-Xun
2004, 25(8): 1471-1473.
Asbtract
(
)
PDF
(544KB) (
)
References
|
Related Articles
|
Metrics
The method of Michael addition reaction of thiophenol with intramolecular hydrogen bond in an aqueous medium was reported. The aqueous reactive medium includes saturated sodium bicarbonate solution and catalytic amount of tetrabutylammonium bisulfate. 2-Hydroxythiophenol,2-aminothiophenol,2-carboxythiophenol,ethyl acrylate and arcylonitrile were selected as model molecules to demonstrate the method. It is found that the reaction can be accomplished rapidly at room temperature with a high yield,and no mercapto-coupling byproduct formed.
Structure Investigation of Water-soluble Polysaccharide HPⅠ Isolated from the Hericium Caput-medusae
WANG Zhao-Jing, LIANG Zhong-Yan, LUO Dian-Hui,
2004, 25(8): 1474-1476.
Asbtract
(
)
PDF
(262KB) (
)
References
|
Related Articles
|
Metrics
A water soluble polysaccharide (HPⅠ) was isolated from the Hericium caput-medusae and examined homogenously by Sephadex G-100 column chromatography,cellulose acetate film electrophoresis and specific optical rotation measurement. This HPⅠconsists of Fuc,Glc and Gal in the molar ratios of 0.423:1:2.110. Its structural features were investigated by methylation and GC-MS analysis,periodate oxidation-Smith degradation,and partial acid-hydrolysis. In addition, enzymatic degradation experiments and GC analysis were applied. The following structure of the highly branched repeating unit was established: 6→)-Gal-(1→6)-Gal-(1→6)-Gal-(1→6)-Gal-(1→6)-Gal-(1→6)-Gal-(1→6)-Gal-(1→6)-Gal-(1→6)-Gal-(1→ 2 ↑ 1 2 ↑ 1 2 ↑ 1 Gal-(1→4)-Fuc Glc-(1→3)-Glc
2
Gal-(1→6)-Glc
3
The activities of HPⅠwere tested in mice. All the samples exhibited high effect of prevention and cure against chronic gastricism.
Internal Noise Stochastic Resonance in a Mesoscopic Oscillating Chemical Reaction System
GONG Yu-Bing, HOU Zhong-Huai, XIN Hou-Wen
2004, 25(8): 1477-1480.
Asbtract
(
)
PDF
(961KB) (
)
References
|
Related Articles
|
Metrics
The influence of internal noise on a mesoscopic oscillating chemical reaction system is numerically studied by using chemical Langevin equations. It is found that internal noise can induce reaction oscillations in the system when the corresponding deterministic system does not oscillate. With the change of the internal noise intensity,the signal-to-noise ratio of the noise-induced oscillation goes through a maximum,which shows the occurrence of internal noise stochastic resonance. Since the magnitude of the internal noise is changed
via
the variation of the system size,these phenomena also demonstrate a kind of system size resonance.
Theoretical Study on the Differences of Interactions Between Pt-Complex Anticancer Drug ZD0473 and Double and Single Strand DNA
JIA Mu-Xin, QU Wen-Wen, CHEN Guang-Ju, LIU Ruo-Zhuang
2004, 25(8): 1481-1484.
Asbtract
(
)
PDF
(1358KB) (
)
References
|
Related Articles
|
Metrics
cis-Amminedichloro(2-methylpyridine)platinum(Ⅱ),also known as ZD0473,is a new Pt-complex anticancer drug rationally designed to circumvent the cisplatin resistance of some tumor cells. The MM/uff//HF/lanl2dz method combining molecular mechanics with quantum chemistry and the solely density function method B3LYP/lanl2dz//6-31G
*
are used to investigate the geometry,interaction and electron structure differences between the adducts of this drug and the same base sequence single and double strand DNA in this paper. The results show that even though the drug molecule can form stable adducts with both the single and the double strand DNA,the double strand adduct has such advantages over the single one as the drug forms comparatively stronger coordinate bonds between Pt and the guanines and better hydrogen bond between the amine and the O6G
8
and the picoline has a higher stereo hindrance which further decreases the drug resistance of tumor cells.
Synthesis,Characterization and Catalytic Properties of Mesoporous Materials with Loading of TS-1 Precursors
WANG Run-Wei, HU Lei, CHU Bin, ZHU Guang-Shan, QIU Shi-Lun
2004, 25(8): 1485-1489.
Asbtract
(
)
PDF
(446KB) (
)
References
|
Related Articles
|
Metrics
TS-1 precursors were loaded and highly dispersed on the surface of mesoporous materials MCM-41 and SBA-15,and these samples are characterized by IR,UV-Vis spectra and other techniques. These results suggest that the samples retain the mesopores channels and characteristic structure of microporous TS-1. The catalytic results show that these materials are more active than conventional mesoporous Ti-MCM-41 and Ti-SBA-15. In the oxidation of large molecule,these materials exhibit a good conversion compared with mesoporous materials and microporous TS-1 especially.
A Multinuclear Solid State NMR Study on Dealumination of Mordenite by Steaming and Acid-leaching
ZHANG Ming-Jin, CHEN Lei, YI De-Lian, ZHENG An-Min, YANG Jun, DENG-Feng, YUE Yong, YE Chao-Hui
2004, 25(8): 1490-1494.
Asbtract
(
)
PDF
(665KB) (
)
References
|
Related Articles
|
Metrics
The steamed and acid-leached mordenite samples were examined by high-resolution solid state
1
H,
29
Si,
27
Al magic angle spinning (MAS) and
1
H/
29
Si cross polarization (CP) NMR spectroscopic techniques in order to study the aluminum species and evaluate the dealumination process during steaming and leaching. The NMR experiments provide a direct evidence for the existence of nonframework four-coordinated Al species,Al(OH)
3
·H
2
O,giving rise to a
1
H resonance at δ 3.0 and a
27
Al shoulder peak at δ 45,which are different from the distorted four-coordinated Al species. At a high temperature,water molecules will favor the formation of these Al species and extra-framework penta- and hexa-coordinated Al species in the
27
Al spectrum at δ 30 and δ 0,respectively.
1
H/
29
Si CP and
1
H MAS NMR showed the presence of an abundance of SiOH and AlOH groups in the dealuminated mordenites during the steaming process.
Resonance Raman Spectroscopy and Density Functional Theory Calculation Investigation of I
2
-cyclohexene Complex
LI Shao-Peng, WU Guang-Ming, ZHENG Xu-Ming
2004, 25(8): 1495-1498.
Asbtract
(
)
PDF
(573KB) (
)
References
|
Related Articles
|
Metrics
Resonance Raman spectra of I
2
-cyclohexene charge-transfer complex were obtained with three excitations at ～300 nm absorption band of the complex. Density functional theory calculations were carried out to examine the structure and normal mode frequencies of the ground state of the complex and its electronic transition energies. The strong absorption band around 300 nm was assigned to
p
z
(I17)→ π
*
(C=C) transition,that is the transition of a
p
z
electron from I atom at C=C terminal to anti-bonding orbital of C=C double bond. The resonance Raman spectra displayed the Raman intensity in the overtones and combination bands of the nominal I—I stretch and C=C stretch modes.This suggested that the complex underwent an obvious valence change in both I—I and C=C.
Synthesis of Strong Solid Acid MoO
3
/ZrO
2
and Application to the Alkylation of Isobutane with Butene
SUN Wen-Dong , XU Li-Ping, LIU Hai-Yan, CHU Ying, WU Yue
2004, 25(8): 1499-1503.
Asbtract
(
)
PDF
(540KB) (
)
References
|
Related Articles
|
Metrics
MoO
3
/ZrO
2
nanoparticles were synthesized in AOT/isooctane reverse micelle system. The transmission electron microscope(TEM) results indicate that the size distribution of nanoparticles is normal and the size of more than 95% particles is between 38 and 60 nm. MoO
3
/ZrO
2
particles was loaded on γ -Al
2
O
3
and present a high dispersity. According to NH
3
-TPD and alkylation,MoO
3
/ZrO
2
particles apparently have more acid sites and higher activity than those prepared by using impregnation and sol-gel method. The yield of C
8
is about 79%.
Theoretical Study on the Potential Energy Surface of the Reaction of Ketenyl Radical(HCCO
&
#183;) with Oxygen(O
2
)
WEI Zhi-Gang, HUANG Xu-Ri, SUN Yan-Bo, SUN Chia-Chung
2004, 25(8): 1504-1506.
Asbtract
(
)
PDF
(151KB) (
)
References
|
Related Articles
|
Metrics
The doublet potential energy surface for the reaction of HCCO radical with molecular O
2
is worked out by the ab initio MO calculations at the G2(B3LYP/MP2/CC) level of theory. Three kinds of possible reaction mechanisms are proposed for the reaction. The first one is the four membered ring reaction mechanism to give products P1 (HCO+CO
2
); the second is the three membered ring reaction mechanism to give products P2 (CO+HCO
2
); the third is the O—O bond broken mechanism to give products P3[O+OCC(O)H] and products P4(O+CO+HCO). Products P1 (HCO+CO
2
) are the major products on the potential energy surface,and products P2 (CO+HCO
2
),P3 [O+OCC(O)H] and P4 (O+CO+HCO) are the minor ones.
Configuration Effect on Intramolecular Electron Transfer Between Durene-bridged Aromatic Redox Centers
LUShen-Zhuang, LI Xiang-Yuan, HE Fu-Cheng
2004, 25(8): 1507-1510.
Asbtract
(
)
PDF
(639KB) (
)
References
|
Related Articles
|
Metrics
Based on the semi-classical theory of electron transfer,quantum chemical calculation at HF/6-31G level was performed for the study of intramolecular electron transfer between durene-bridged 2,5-dimethoxy-4-methylphenyl and its cation. Two configurations are adopted. After the geometric optimizations of the electron-localized states,a linear reaction coordinate ξ was introduced to determine the transition state. The electronic transfer matrix elements
V
AB
are calculated by variation principle. The non-equilibrium solvation correction was taken into account. The electron transfer rate and reorganization energy obtained by theoretical calculation are consistent well with the experimental values. The electronic transfer matrix elements at different dihedral angles between bridge and redox centers were obtained. In order to show the different contribution to this value,the electronic transfer matrix elements were divided into two parts: through space and through bond. The latter is further divided into σ bond contribution and π bond one. It has been concluded that the through π bond coupling is proportional to the square of cosine of dihedral angle. This conclusion was explained qualitatively.
Synthesis,Characterization and Performance of PtSn/C Electrocatalyst for Direct Ethanol Fuel Cell
JIANG Lu-Hua, ZHOU Zhen-Hua, ZHOU Wei-Jiang, WANG Su-Li, WANG Guo-Xiong, SUN Gong-Quan, XIN Qin,
2004, 25(8): 1511-1516.
Asbtract
(
)
PDF
(791KB) (
)
References
|
Related Articles
|
Metrics
PtSn/C electrocatalysts(Pt
2
Sn/C,Pt
3
Sn/C,Pt
4
Sn/C) with different
n
(Pt)/
n
(Sn) ratios were prepared by a modified polyol process and characterized by XRD,TEM and cyclic voltammetry (CV) techniques. TE
M
r
esults show that the mean size of metal particles in the catalysts prepared is smaller than 4 nm with a sharp distribution. XRD results show that all the in-house catalysts have fcc crystalline structure. The crystal lattice parameter
a
fcc
of Pt in Pt
3
Sn/C is 0.394 6 nm,which implies that alloying of Pt and Sn could dilate the cell lattice parameter of Pt. CV and H
2
chemisorption results show that the unit activity of PtSn/C increased. CV results also show that Pt
3
Sn/C has the highest activity for ethanol oxidation. Single cell tests with PtSn/C as the anode catalysts show that maximum output power increased with increasing Sn molar fraction,and then decreased. The difference of catalytic activity between PtSn/C with various Sn molar fractions may be caused by the particle size effect,alloying degree between Pt and Sn and the cell internal impedance. The EDX analyses of the Pt
3
Sn/C catalyst before and after stabilization test show that the content of both Pt and Sn decreased. The life of PtSn/C catalysts needs to be improved further.
A Study of Dynamics of Excited State 1,3-Dichrolobenzene with Ultrafast Pulse Laser
WANG Yan-Qiu, YUAN Li-Wei, WANG Li, HE Guo-Zhong, ZHANG Zhi-Gang, WANG Qing-Yue
2004, 25(8): 1517-1520.
Asbtract
(
)
PDF
(457KB) (
)
References
|
Related Articles
|
Metrics
A new CPA femtosecond laser system was built up. The output of the system is centered at 808 nm with 8 mJ/pulse power and 60 fs pulse width at 20 Hz repetition rate. In this paper,we present the detail description of this femtosecond laser system and our initial experimental investigation of de-excited dynamics of 1,3-dichrolobenzene in its
S
1
excited state with the laser system,combined with the time-flight mass spectrometer,pump-probe technique and supersonic molecular beam. Quantum beat phenomenon of 1,3-dichrolobenzene in its
S
1
excited state was clearly observed for the first time in real time scale. The lifetime constant and the quantum beat frequency of
S
1
excited state were obtained. The photodissociation process of 1,3-dichlorobenzene is illuminated.
Ab initio Calculation of the Formation Energies of Lithium Substitutions in InSb
LIU Hui-Ying , HOU Zhu-Feng, ZHU Zi-Zhong, HUANG Mei-Chun, YANG Yong
2004, 25(8): 1521-1524.
Asbtract
(
)
PDF
(926KB) (
)
References
|
Related Articles
|
Metrics
An ab initio calculation method with plane-wave basis and norm-conserving pseudopotentials was employed to investigate the electronic structures and formation energies of lithium substitutions in InSb in several cases. The changes of volumes, charge densities,band structures and electronic density of states for the lithium substitutions in InSb were discussed. The results show that the formation energies of lithium substitutions in zinc-blende InSb were all around -2.2 eV per Li atom,this results also indicate that the substitution of Li can not occur at the early stage of insertion when Li is not yet intercalated into the clearance space of InSb,which are in consistent with those of experiments.
An Anion Chemosensor Based on Flavone Quasi-crown Ether Metal Complex
ZHOU Li-Li, LI Hua-Ping, WANG Hui, FENG Lin, ZHANG Xiao-Hong, WU Shi-Kang
2004, 25(8): 1525-1528.
Asbtract
(
)
PDF
(483KB) (
)
References
|
Related Articles
|
Metrics
A novel metal complex [Ca(L)] 2+ (1)[or [Mg(L)] 2+ (2)] based on the flavone derivative with a quasi-crown ether(4′-(dimethylamino)-3,6-(tetraethylene glycol)flavone) was synthesized and studied as anion-binding receptors. Remarkable color change of host 1 or 2 induced by the complex formation with HSO
4
-
(or H
2
PO
4
-
) was observed. The UV-Vis spectroscopic titration experiments indicated the formation of 1:1 stable complexes between 1 or 2 and HSO
4
-
. HSO
4
-
(or H
2
PO
4
-
) can also be selectively detected by the fluorescence method,which is even more sensitive than the UV-Vis spectroscopic method. The binding manner using double binding sites and possible structures formed between complex 1 or 2 and selected anions were proposed. The results showed the dye-containing metal complexes could act as the efficient and selective chromogenic and fluorescent reagents for anion sensing.
Theoretical Study on S
3
Molecule Structure and Most Probable Dissociation Process
WANG Zhi-Gang, AO Shu-Yan, YAN Bing, PAN Shou-Fu, YU Jun-Hua
2004, 25(8): 1529-1532.
Asbtract
(
)
PDF
(215KB) (
)
References
|
Related Articles
|
Metrics
Using quantum chemical ab initio method,the optimized geometry structure of S
3
molecule in ground state and several low-lying excited states were obtained. In
C
2v
and
C
s
symmetry,we study the dissociation processes and the PESs(potential energy surface) of the low-lying states. In both symmetries,we all obtained optmized dissociation paths on the corresponding potential energy surface.
Effect of Different Electrode Materials and Addition of Different Metal Ions on Cr
3+
Anode Oxidation
LI Ke-Chang, ZHANG Heng-Bin, CAO Xue-Jing, LIN Hai-Bo
2004, 25(8): 1533-1536.
Asbtract
(
)
PDF
(191KB) (
)
References
|
Related Articles
|
Metrics
By measurements of cyclic voltammetry and current efficiency,the anodic oxidation behavior of Cr
3+
at PbO
2
,graphite and Pt electrodes was studied. It is found that PbO
2
is a higher active electrode material for Cr
3+
oxidation. The effect of addition of Ag
+
,Mn
2+
,Co
2+
on Cr
3+
oxidation was also explored. The results indicate that the electrocatalysis of Ag
+
is very obvious.
Crystal Structure and Enthalpy Change of Formation Reaction for Et
2
NH
2
[Nd(S
2
CNEt
2
)
4
]
GAO Sheng-Li, CHEN San-Ping, REN Yi-Xia, JIAO Bao-Juan, XIE Gang, SHI Qi-Zhen
2004, 25(8): 1537-1540.
Asbtract
(
)
PDF
(330KB) (
)
References
|
Related Articles
|
Metrics
The solid complex of neodymium chloride hydrate with diethylammonium diethyldithiocarbamate(D-DDC) Et
2
NH
2
[Nd(S
2
CNEt
2
)
4
] was synthesized in dry N 2 atmosphere and absolute alcohol. The composition of the complex was determined by chemical and elemental analyses. The crystal structure showed that Nd 3+ was coordinated by eight sulfur atoms with four ligands. The coordination polyhedron can be described as a distorted dodecahedron. It crystallizes in a monoclinic system,space group P2 1/n with
a
=1.375 17(14) nm,
b
=2.114 6(2) nm,
c
=1.446 41(15) nm, β =102.028(2)°,
Z
=4. The enthalpies of solution of neodymium chloride hydrate and D-DDC in absolute alcohol at 298.15 K and the enthalpy change of liquid-phase reaction of formation for complex Et
2
NH
2
[Nd(S
2
CNEt
2
)
4
] was determined by a microcalorimeter as(-17.89±0.096),(50.280± 0.151 ) and (-10.116±0.065) kJ/mol, respectively. The enthalpy change of the solid-phase reaction of formation was obtained through a thermochemical cycle.
Preparation of Regular Coiled Carbon Nanotubes by Reduced-pressure Catalytic Chemical Vapor Deposition
LU Mei, GUO Xin-Yong, WANG Zhe, LI Hu-Lin
2004, 25(8): 1541-1544.
Asbtract
(
)
PDF
(283KB) (
)
References
|
Related Articles
|
Metrics
Regular coiled carbon nanotubes were prepared by catalytic chemical vapor deposition(C=CVD) on finely divided Co nano-particles supported on silica gel at reduced pressure and lower gas flow rates. The morphology and the distribution of the geometrical parameters of the coiled carbon nanotubes were examined by TEM,while the graphitization of coil tube,coil bend and coil node were analyzed by HRTEM. The influences of the pH values and the reaction pressure on the growth of the coiled carbon nanotubes were also discussed. With this modified C=CVD approach,the amorphous carbon generally coated on the carbon nanotubes was greatly decreased.
Reaction Kinetics in Polyesterification of AA/HPHP and AA/NPG
QIAO Qian, ZHANG Wei-Lu, ZHANG Dong, LIU Chun-Yan, TIAN Yi-Guang, ZHAO Ya-Juan
2004, 25(8): 1545-1548.
Asbtract
(
)
PDF
(1118KB) (
)
References
|
Related Articles
|
Metrics
A new general kinetic equation was derived in which the effect of the removal of condensation water was taken into account completely,and was applied to the polyesterification kinetic study of AA/HPHP and AA/NPG. It was found that the reaction order of self-catalyzed polyesterification was not constant. For these polyesterifications,the reaction order was 2.5 at a low temperature,while 3.0 at a high temperature. Moreover,if the effect of the removal of condensation water was neglected,the kinetic parameter would have more deviation. For polyesterifications of AA/HPHP and AA/NPG,the relative deviation of activation energy was 21.51%,11.33%,respectively. The relative deviation of frequency factor was 97.4%,87.96%,respectively.
Preparation and Visible-light Photocatalytic Properties of Polyoxometalate-doped Anatase Nanocrystal Na
4
W
10
O
32
/TiO
2
with Mesoporous Structure
XU Yun-Ting, LI Li, YU Xiao-Dan, GUO Yi-Hang
2004, 25(8): 1549-1551.
Asbtract
(
)
PDF
(535KB) (
)
References
|
Related Articles
|
Metrics
A simple and rapid process has been developed for the preparation of mesoporous anatase TiO
2
crystalline particles coupled by homogeneously dispersed Na
4
W
10
O
32
at a lower temperature ( 200 ℃ ) by combining sol-gel and programmed temperature hydrothermal methods. The composite,Na
4
W
10
O
32
/TiO
2
,has a uniform mesopore distribution with the average pore diameter of 3.8 nm,and its BET surface area is 178.4 m
2
/g. The average size of the composite is below 10 nm. This new photocatalyst exhibited a visible-light photocatalytic activity to decompose para -thion-methyl.
Selective Hydrogenation of p-Chloronitrobenzene over Ru-Pt/γ-Al
2
O
3
Catalyst Modified by Metal Cations
ZHAO Song-Lin, CHEN Jun-Ru, ZHOU Ya-Fen, XIE Yong-Mei, LI Xian-Jun
2004, 25(8): 1552-1554.
Asbtract
(
)
PDF
(214KB) (
)
References
|
Related Articles
|
Metrics
The bimetallic catalyst Ru-Pt/γ -Al
2
O
3
was prepared by impregnating H
2
PtCl
6
and RuCl
3
aqueous solution in the presence of PVP(40 000). Its catalytic performance in selective hydrogenation of p -chloronitrobenzene ( p -CNB) was studied. The results indicate that the activity of Ru-Pt/ γ -Al
2
O
3
[
n
(ruthenium):
n
(platinum)=4:1] is much higher than that of Ru/ γ -Al
2
O
3
,while the amount of dehalogenation product(aniline) and other by-products are much fewer than that by using Pt/ γ -Al
2
O
3
as the catalyst. There is synergistic effect of ruthenium and platinum in bimetallic catalyst for selective hydrogenation of p -CNB. Under the reaction conditions t =50 ℃, p H
2
= 1.0 MPa, reaction time 60 min,
n
(substrate):
n
(total amount of metal content)=1000:1,the conversion of p -CNB and the selectivity to p -chloroaniline( p -CNA) by using Ru-Pt/γ -Al
2
O
3
as the catalyst are 48.2% and 85.9%,respectively. The effect of other metal cations(introduced to the reaction system with the corresponding metal chloride solution) on the reaction was investigated. It was found that catalytic performance of Ru-Pt/ γ -Al
2
O
3
could be greatly improved by modfication of some metal cations. When Co
2+
and Ni
2+
were used as modifiers for the catalyst Ru-Pt/ γ -Al
2
O
3
under above mentioned reaction conditions,the conversions of p -CNB increase to 74.5% and 87.8%,as well as the selectivities of p -CAN increase to 98.9% and 99.4%,respectively. Fe
3+
and Sn
4+
were the best modifiers for Ru-Pt/ γ -Al
2
O
3
under the same reaction conditions. The conversions of p -CNB and the selectivities of p -CAN can reach 100% and >99.0%,respectively. However,the catalysts can be poisoned by Zn
2+
and Sn
2+
.
Nuclear Magnetic Resonance Relaxation of Cohesional Entanglement of Nylon 6 Chains in Trifluoroacetic Acid Solution
GAO Hong-Chang, MAO Shi-Zhen, YUAN Han-Zhen, DU You-Ru
2004, 25(8): 1555-1558.
Asbtract
(
)
PDF
(576KB) (
)
References
|
Related Articles
|
Metrics
An unambiguous assignment of the main
1
H NMR resonance of nylon 6 in trifluoroacetic acid (TFA) solution was carried out by using a combination of 1D and 2D NMR heteronuclear technique (HMQC). The spin-spin relaxation time measurements at different temperatures provide the information about cohesional entanglements of main chains among the macromolecules and the dynamics of nylon 6 polymer at different temperatures in TFA solution. The results show that the methylene groups of the nylon 6 main chains are cohesionally entangled in different degrees at the ambient temperature. The farther the methylene group from the CO and NH groups,the more intensely entangled they are. The entanglements of the methylene groups adjacent to the CO and NH groups,are less pronounced owning to the formation of interchain hydrogen bonds. These entanglements are gradually weakened by the thermal motion upon increasing temperature. The absence of the variation in t 2H of the NH proton with the charge of temperature and the decrease in t 2H of the TFA protons with the increase in temperature give an evidence about the dissociation of the interchain hydrogen bonds among the nylon 6 molecules and the formation of hydrogen bonds between TFA protons with the NH and CO groups of nylon 6 set free by increasing temperature.
A Monte Carlo Simulation of Morphology and Structure for Thin Films of Symmetric Triblock Copolymer after Quenching and Annealing
NIE Zhi-Hong, SHI Tong-Fei, AN Li-Jia
2004, 25(8): 1559-1562.
Asbtract
(
)
PDF
(713KB) (
)
References
|
Related Articles
|
Metrics
Self-assembly thin films of symmetric triblock copolymer after annealing and quenching were examined by an effective Monte Carlo simulation method. The defects in the ordered lamellae of the thin films after quenching,which were dependent on the initialization of copolymer melts,are removed in the thin films after annealing. The mean-square gyration radius and end-to-end distance of copolymer chains in the thin films after annealing are smaller than those in the thin films after quenching because of the complete relaxation of polymer during annealing. We also find that the density of A block in the region near to the surface is higher than that in the interior of the thin films. As a result,it is different from the thin films of symmetric A n B n diblock copolymer,in which surface ordering forms before the interior,that ordering phenomena occurs first in the interior region in the thin films of symmetric A n B m A n triblocl copolymer.
A Novel Sulfonated Poly(ether ether ketone ketone)s Used as PEMFC
LI Xian-Feng, NA Hui, LU Hui
2004, 25(8): 1563-1566.
Asbtract
(
)
PDF
(954KB) (
)
References
|
Related Articles
|
Metrics
A new sulfonated monomer 1,4-bi(3-sodium sulfonate-4-fluorobenzoyl)benzene was prepared by sulfonation of 1,4-bi(4-fluorobenzoyl)benzene with fuming sulfuric acid. Then a series of sulfonated PEEKKs derived from the monomer were synthesized via aromatic nucleophilic substitution polycondensation of phenolphthalein with different molar ratios of 1,4-bi(3-sodium sulfonate-4-fluorobenzoyl)benzene to 1,4-bi(4-fluorobenzoyl)benzene. The structure and property of the polymers were characterized and studied. Most of the polymers were easily cast into tough membranes. The membranes show a high ion exchange capacity and very good prospective in proton exchange membranes(PEM) usage.
Synthesis,Characterization and Application of Palygorskite/Polyacrylamide Inorganic-organic Hybrid Flocculent
WANG Meng, QIAN Jin-Wen, ZHENG Bao-Qing, YANG Wu-Yuan, JIANG Wei-Feng, FANG Zuo, YE Ying
2004, 25(8): 1567-1571.
Asbtract
(
)
PDF
(356KB) (
)
References
|
Related Articles
|
Metrics
Acid-activated palygorskite(PGS) reacted with ethanolamine hydrochloride(EACl),and the modified palygorskite(PGS-EACl) was obtained. The polymerization of acrylamide was initiated by heterogeneous redox initiator system, composed of reductive agent PGS-EACl together with oxidant Ce
4+
,and the palygorskite/polyacrylamide(PGS/PAM) hybrid was obtained. The product was characterized by
1
H NMR,FTIR,viscosimetry and specific conductivity method,and the result showed an abnormal viscosity and conductivity behavior in water. It can be interpreted in terms of ion bond structure(PGS
Θ⊕
NH
3
R) in PGS/PAM hybrid. The influence of dosage of PGS-EACl, polymerization time,and monomer concentration on the [ η ] of the PGS/PAM hybrid was investigated,and it is found that the [ η ] of the hybrid increases with increasing polymerization time differing from conventional free-radical polymerization. Flocculating effect of PGS/PAM hybrid was better than that of pure PAM for both mass fraction 0.25% kaolin suspension and mass fraction 0.5% hematite suspension,respectively.
Microphase Separation Structure Formed in GMA/St Multi-monomer Melt Grafted Polypropylene
CHEN Bin, ZHANG Jing-Chun, XIE Xu-Ming
2004, 25(8): 1572-1575.
Asbtract
(
)
PDF
(549KB) (
)
References
|
Related Articles
|
Metrics
The glycidyl methacrylate(GMA) and styrene(St) multi-monomer grafted polypropylene(PP),PP-g-(GMA-co-St),with various grafting degrees were prepared by melt-grafting process. The homo-PP and ethylene-co-polypropylene with different contents of ethylene were chosen to be backbone PP for the grafting process. After purification,PP-g-(GMA-co-St) was stained by RuO
4
,and its microphase morphology was observed by Transmission Electron Microscope(TEM). The microphase separation morphology, i.e . spherical long-range order structure was found in the grafted PP. Such nano-structure morphology formed in melt-grafted polymer was unique and original. The effects of E block fractions in EP copolymer and grafting degree on the microphase morphology were discussed. This study indicated that even in the melt grafting system,where molecular weight and molecular architecture are both multi-dispersed,copolymers with long grafts could also be separated in a microphase into long-range order structures.
Construction of Biodegradable Multilayer Films via Layer-by-layer Self-assembly as Gene Delivery System
REN Ke-Feng, JI Jian, SHEN Jia-Cong
2004, 25(8): 1576-1578.
Asbtract
(
)
PDF
(499KB) (
)
References
|
Related Articles
|
Metrics
Biodegradable multilayer films of alternating poly- L -lysine(PLL) and deoxyribonucleic acid(DNA) layers were fabricated onto quartz substrates by the layer-by-layer(LbL) self-assembly method. UV-Visible spectra showed that PLL and DNA can successfully be adsorbed and form multilayer films via LbL. Degradation experiments were carried out with enzymes. AFM was utilized to measure the changes of thickness of multilayer films. The gradual decrease of thickness of multilayer films with the increase of degradation time was observed. In our experiments, about 85% of films was degraded in 35 h. Our study provided a novel gene delivery system using LbL method,which may be applied to gene therapy.
Preparation of Arrayed Cluster of Poly(vinyl pyrrolidone)Nano-tube by Template Method
QIAO Jun-Juan, ZHANG Xiao-Hong, LIN Zhang-Da, WU Shi-Kang
2004, 25(8): 1579-1581.
Asbtract
(
)
PDF
(460KB) (
)
References
|
Related Articles
|
Metrics
Arrayed clusters of poly(vinyl pyrrolidone) (PVP) nano-tube were prepared by using porous alumina membrane treated with hydrophobic materials as the template. Fluorescence spectrum method was applied to the characterization of modified pore walls of template by solvents with different polarities. And the relationship between PVP nano-tube formation and modification of pore walls of template was discussed preliminary.
Preparation of Amphiphilic Oligomers of Gd(Ⅲ) Complexes and Their Liver-selective MRI Property
BAI Zheng-Wu, YU Kai-Chao, ZHUO Ren-Xi
2004, 25(8): 1582-1584.
Asbtract
(
)
PDF
(315KB) (
)
References
|
Related Articles
|
Metrics
Diethylenetriaminepentaacetic dianhydride was co-polymerized with dodecyl ester and benzyl ester of lysine,and octodecyl ester and benzyl ester of lysine respectively to give two terpolymers. These two terpolymer ligands were reacted with GdCl
3
to afford amphiphilic oligomers of Gd(Ⅲ) complexes. These new ligands and Gd(Ⅲ) complexes were characterized by IR,
1
H NMR and elemental analysis. The oligomeric complexes show a higher relaxivity as compared to that of Gd(DTPA) which is widely used in clinic diagnoses. The Gd(Ⅲ) complex derived from octodecyl ester demonstrated liver-selective enhancement for MR imaging of Wistar rat. The ratios of signal to noise ( S/N ) in the proton intensity imaging were enhanced,respectively,by 15%,27%,and 36% at the time of 5,30 and 45 min after injection of this complex.
Author Login
Peer Review
Editor Work
Office Work
Special Issues
More...
Download
More...
Links
More...
