Table of Content

10 February 2016, Volume 37 Issue 2

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Polymer Chemistry

Preparation and Properties of Nanocomposites Based on Polyimide and Polyfluorinated Surfactant-pillared Layered Double Hydroxide^†

GUO Haiquan, MA Xiaoye, JIN Rizhe, KANG Chuanqing, QIU Xuepeng, GAO Lianxun

2016, 37(2):  403-408.  doi:10.7503/cjcu20150443

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Layered double hydroxide was modified with polyfluorinated surfactant via anion-exchange intercalation procedure. The nature of the interlayer anions, the morphology and the thermal stability of the fluorinated LDH(LDH-FS) were investigated by infrared spectrum, X-ray diffraction and thermogravimetry analysis. The interlayer space was expanded from 0.76 nm to 2.52 nm and the microenvironments with polyfluorinate phase were formed. LDH-FS based polyimide(PI) nanocomposites were prepared by the in situ polymerization and characterized. LDH-FS was well dispersed in the polyimide matrix. The gas barred, mechnical and dielectric properties of the LDH-FS/PI nanocomposites were synthetically effected by the exfoliated inorganic nanolayers and polyfluorocarbon chain.



Content

Cover and Content of Chemical Journal of Chinese Universities Vol.37 No.2(2016)

2016, 37(2):  0-0. 

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Reviews

Application of Polymers in Fluorescence Analysis^†

SONG Chunxia, YANG Xiaohai, WANG Kemin, WANG Qing, LIU Jianbo, HUANG Jin, LI Wenshan, HUANG Haihua, LIU Wei

2016, 37(2):  201-212.  doi:10.7503/cjcu20150796

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Polymers are macromolecular compounds built up from single or numerous kinds of monomers. The common materials in production and living(for example protein, nucleic acid, starch, fiber, plastic and rubber, etc.) are included in this category. Owing to the unique properties after polymerization and their monomers, polymers have been extensively used in fluorescence analysis as fundamental materials: target recognition can be realized through polymers interact with target molecules through intermolecular forces(hydrogen bond, hydrophilic and hydrophobic function, and van der Waals’ force, etc.); certein polymers can transform the molecular recognition event to easily recognizable fluorescence signal, and then fluorescence signal transformation and amplification could be realized; certein polymers have been used as framework of flourescence probes, therefore the recognition capacity of fluorescence probes are improved due to multivalency effect, and multifunction devices are constructed based on the conjugation of different functional units. In this paper, the research and application of polymers in molecular recognition, signal transformation and as framework of probes were reviewed.



Conducting Polymer and Its Nanocomposites with Thermoelectric Properties^†

MAO Jianxin, NIE Guangdi, LU Xiaofeng, GAO Mu, WANG Wei, WANG Ce

2016, 37(2):  213-220.  doi:10.7503/cjcu20150506

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With the development of modern science and technology and the increasingly serious environmental crisis, the thermoelectric materials and their resulting devices have attracted considerable attention. Compared to inorganic thermoelectric materials, organic polymer are light weight, flexibility, low thermal conductivity and solution-processablethermoelectric materials that become the focus in this field. Currently, the theoretical and experimental studies have proved that thermoelectric materials with low dimension would exhibit good thermoelectric properties for the practical application. Here, we highlight recent work from different laboratories, including our own, toward the design and the characterization of low-dimension polymer thermoelectric materials, with a particular emphasis on the conducting polymers.



Letter

Modification of Baculovirus with Folic Acid based on Phospholipids Self-insertion in Host Cells^†

WANG Liying, WEN Li, LÜ Cheng, LIN Yi, PANG Daiwen

2016, 37(2):  221-223.  doi:10.7503/cjcu20150886

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Baculovirus has the advantages such as outstanding biosafety, large cloning capacity and non-replication in the transduced cells. However, their in vivo applications are hampered for lacking of specificity. Therefore, modification of baculovirus with targeting molecules is urgently needed. Herein, a method is proposed for the modification of folic acid(FA) on baculovirus based on phospho-lipids self-insertionin host cells. Immunofluorescent colocalization and transmission electron microscope(TEM) results showed that the modified baculovirus kept their integrity while maintaining their infectivity. Thus the method offers opportunities for the development of tumor-targeting gene vectors and vaccines.



Articles: Inorganic Chemistry

Preparation of Hyaluronic Acid-modified Mesoporous Silica-coated Gold Nanorods and Their Application in Chemo-Photothermal Therapy of Cancer

JIN Xintian, LIU Gang, LI Junzhe, SUN Lili, WANG Junrong, LI Junfeng, LI Pei, CHEN Wenqing, WANG Qiang, TONG Ti

2016, 37(2):  224-231.  doi:10.7503/cjcu20150662

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A tumor-targeting multifunctional drug delivery system was obtained through modifying mesoporous silica-coated gold nanorods with biocompatible hyaluronic acid. The experimental results demonstrated hyaluronic acid could be modified on the surface of mesoporous silica through the formation of amide bond. The resulted drug carrier could realize enzyme-responsive drug release in the presence of hyaluronidase. UV-Vis spectra showed that the system had a high absorption in the near infrared region, thus exhibiting photothermal effect upon the near infrared light irradiation. Besides, cell experiments demonstrated the multifunctional drug carrier could effectively target CD44 over-expressed breast cancer cells. It could be accumulated in the tumor region through CD44 receptor mediated endocytosis. Combining chemo- and photothermal therapy resulted in improved tumor apoptosis efficiency.



Analytical Chemistry

Highly Selective Ratiometric Fluorescent Probe for Hg²⁺Based on Fluorescence Resonance Energy Transfer Between 1,8-Naphthalimide and Rhodamine B^†

CHEN Jiayi, SU Wei, WANG Enju

2016, 37(2):  232-238.  doi:10.7503/cjcu20150563

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A ratiometric fluorescent probe(RN) was developed based on rhodamine B and 1,8-naphthalimide which were linked together by an amido linkage. In CH₃OH/CH₃CN/HEPES buffer solution(pH=7.2), free RN showed absorption maximum at 412 nm. The presence of Hg²⁺ could induce an intensive absorption at 556 nm. The change of absorption spectrum resulted in a color change from light green to orange in response to Hg²⁺. Significantly, the probe RN gave rise to a ratiometric fluorescent response to Hg²⁺. Upon the addition of Hg²⁺, a significant fluorescence enhancement at 580 nm and meanwhile the gradual disappearance of the emission at 540 nm were observed, which were ascribed to the fluorescence resonance energy transfer(FRET) from 1,8-naphthalimide moiety to the ring-opened rhodamine B moiety. Accompanying the change of fluorescence spectra, the significant fluorescence color changed from green to orange occurred, which could be used for naked-eye detection of Hg²⁺. The ratiometric fluorescence signal for Hg²⁺ was not affected by other coexisting mental ions.



Anti-diabetic Drugs Detection by Raman Spectrometry with Molecular Imprinted Composite Membrane^†

JIA Hua, YIN Ruilin, ZHONG Xu, XUE Min, ZHAO Yu, MENG Zihui, WANG Qunjie

2016, 37(2):  239-245.  doi:10.7503/cjcu20150533

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Some artificially synthesized anti-diabetic drugs are frequently found in health products to enhance their curative efficacy. Based on the specific recognition characteristics of molecularly imprinted technology, two kinds of molecularly imprinted composite membranes were prepared with dummy template of guanidine hydrochloride and 4-(2-aminoethyl)-benzene sulfonamide. The adsorption capacities of these two membranes to metformin hydrochloride, phenformin hydrochloride and glibenclamide were studied. Meanwhile, surface enhancement Raman spectrometry(SERS) to determine the target chemicals was established and employed in the membrane detection after infiltrated in the health products extract solution. The influence of nano-silver particles on the membrane to SERS was also studied. The detection limits of metformin hydrochloride, phenformin hydrochloride and glibenclamide are 5, 5 and 10 mg/mL, respectively. This method was also proved by several pieces of real samples.



Organic Chemistry

Synthesis and Antibacterial Activities of 5-Methyl-1,2,4-triazole-3-thione Glucosides Compounds^†

WANG Hongyun, LIU Jinbiao, LU Junrui, YING Ming, YANG Xuyun, YANG Shuxun, MA Yao

2016, 37(2):  246-253.  doi:10.7503/cjcu20150730

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Ten novel compounds of 5-methy-4-(N-substituted-phenyl) imino/amido-3-S-(2',3',4',6'-tetra-O-acetyl-β-D-glucopyranoside)-1,2,4-triazole(2a—2e and 5a—5e) were synthesized via glycosylation of 5-methy-4-(N-substituted-phenyl) imino/amido-1,2,4-triazole-3-thiones with bromo-2,3,4,6-tetra-O-acetyl-β-D-glucopyranoside in acetone in the presence of potassium hydroxide. Subsequently, ten novel compounds of 5-methy-4-(N-substituted-phenyl) imino/amido-3-S-(β-D-Glucopyranosyl)-1,2,4-triazole(3a—3e and 6a—6e) were generated by deacetylate reaction in the system of sodium methylate, methanol and dichloromethane. The structures of all compounds were confirmed by ¹H NMR, ¹³C NMR, IR and HRMS spectra. The results of preliminary bioassay suggested that nearly all of the new compounds exerted variable inhibitory activity against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Monilia albican. Especially, compounds 3d and 3e had lower minimum inhibitory concentration values on four tested strains which showed the strong broad-spectrum antimicrobial activity and great development potential.



Metal-free C3—H Acetoxylation of Indoles Promoted by PhI(OAc)₂^†

WANG Liang, QU Xing, LI Zhan, GU Changhan, HU Siqian

2016, 37(2):  254-260.  doi:10.7503/cjcu20150716

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3-Substituted indoles are common structural motifs in a series of natural products, pharmaceuticals and biologically active compounds. Metal-free reaction was emerged as one of the most powerful tools for functionalization of indoles due to its environment friendly features. In this work, the metal-free C3—H acetoxylation of indoles and PhI(OAc)₂ was developed. The optimized reaction conditions were established by examination of the substituent, temperature and amounts of PhI(OAc)₂. A series of 3-acetoxyindoles could be obtained in HOAc at 60 ℃ without additives. The yield of product ranged from 45% to 86%. The structures were characterized by infrared(IR), nuclear magnetion resonance(NMR), high resolution mass spectra(HRMS) and X-ray diffraction techniques and a possible reaction mechanism was then proposed. Moreover, this reaction system was also feasible in a gram-scale reaction without significant decrease in the product yields.



Structural Characterization, Antioxidant Activity and Immunomodulatory Activity of the Polysaccharide LRLP3 from Leaves of Lycium ruthenicum Murra^†

LIU Yang, YIN Lu, GONG Guiping, PENG Yifang, HUANG Linjuan, WANG Zhongfu

2016, 37(2):  261-268.  doi:10.7503/cjcu20150690

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A combination of chemical and instrumental analysis was performed to investigate the structural characterization and biological activity of a polysaccharide LRLP3 which was isolated from the Lycium ruthenicum leaves. The results demonstrated that LRLP3 was a highly branched polysaccharide with a backbone of (1→3)-linked-βGalp substituted at C-6 position by galactosyl. The branches were composed of(1→6)-linked-βGalp,(1→4)-linked-βGalp,(1→3)-linked-αAraf and βArap,(1→5)-linked-αAraf, and (1→2, 4)-linked αRhap, and the terminal residues were αAraf, βGalp and βGlcp. Additional, LRLP3 had strong reducing power, could significantly scavenge DPPH, hydroxyl and superoxide free radical, could effectually inhibit Cu²⁺/H₂O₂ induced protein damage and H₂O₂ induced cell damage in vitro. Meanwhile, immunological assay showed that LRLP3 could stimulate proliferation of spleen lymphocytes significantly with or without mitogens(ConA or LPS) in vitro. Therefore, LRLP3 was a natural arabinogalactan which had the potential function of antioxidant and immunoloregulation.



Metal-free Thiolation of C(sp³)—S Bond Adjacent to an Oxygen Atom^†

YAN Dong, TONG Mengliang

2016, 37(2):  269-273.  doi:10.7503/cjcu20150465

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The formation of C—S bonds is one of the most important transformations in organic chemistry due to the high prevalence of sulfur-containing molecules of biological and pharmaceutical relevance. Cross-dehydrogenative coupling(CDC) is more atom economical and environmentally friendly than traditional cross-coupling reactions. A facile and transition metal-free methodology for construction of C(sp³)—S bond was herein reported. With ditertbutyl peroxide(DTBP) as oxidant and thiophenol as thioetherification regent under 120 ℃, the high atom-efficiency and selective system offered the thiobenzylethers as products in acceptable to good yields. These new compounds were characterized via infrared(IR), nuclear magnetic resonance(NMR), and mass spectrometry(MS). The possible mechanism for the reaction was suggested as followed: benzyl ethers was oxidized by DTBP to generate intermediates A, which further reacted with thiophenol to form desired products. This direct thiolation method is a new protocol for the construction of C—S bonds, which might be very valuable and attractive in sulfur chemistry and radical chemistry.



Active Structure Protection of Monoclonal Antibody Fusion Protein Etanercept^†

PAN Qi, LI Daixi, GUO Baisong, YANG Chunsheng, YANG Zhi

2016, 37(2):  274-280.  doi:10.7503/cjcu20150695

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The thermodynamic stability of etanercept in different concentrations of the protective agent was investigated. The approaches of umbrella sampling and steered molecular dynamic simulation were adopted to study the dissociation of dimer etanercept with Gromacs software and amber99sb-ildn united atomic force field. The results indicated that the trehalose has ability to enhance the stability of dimer etanercept, and the protective effect of etanercept with trehalose and mannitol is better than with pure trehalose. In addition, the type of protective agent and alternative specific adsorption position can impact the effect of protecting active structure of etanercept observably.



Transformation of Minor Ginsenoside Rd and CK by Recombinant Thermostable β-Glucosidase^†

XU Chunchun, YU Bohao, WANG Honglei, LI Jing, LIU Shuying, YU Shanshan

2016, 37(2):  281-289.  doi:10.7503/cjcu20150536

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Ginsenosides are the principle components that are responsible for the biological and pharmacological activities of ginseng. In this study, biotransformation of ginsenside Rd and CK by recombinant β-glucosidasse(Fpglu1) was studied by high performance liquid chromatography(HPLC). Structure modeling and molecular docking studies were performed to study the interaction between the protein and the ginsenosides. The results showed that ginsenoside Rd and CK could be transformed from major ginsenosides Rb₁, Rb₂ and Rc by Fpglu1. The K_m values for Rb₁, Rb₂ and Rc were 0.318, 1.840 and 5.269 mmol/L, and the k_cat values were 144.191, 0.572 and 0.011 s^-1, respectively. The highest productivity of ginsenoside Rd and CK were 60% and 93% with biotransformation time of 6 and 102 h, respectively. Molecular docking studies show that Glu194 and Glu367 are key active site residues and the predicted inter-energy exhibits linear relations to experimental K_m values and k_cat values.



Physical Chemistry

Preparation and Electrochemical Performance of 3D-nanohole PVA/a-MWCNTs Hydrogel Electrode Membrane^†

LIU Shumin, ZHENG Yudong, LI Wei, SUN Yi, YUE Lina, ZHAO Zhenjiang

2016, 37(2):  290-296.  doi:10.7503/cjcu20150743

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On the basis of moderate acidification of multiwalled carbon nanotubes(MWCNTs), polyvinyl alcohol(PVA)/a-MWCNTs hydrogel electrode membrane with three-dimensional nanohole was prepared by electrophoretic deposition technology and cycle freeze-thaw process. The electrode membrane has high electrical activity area, low surface charge transfer resistance, high hydrophilicity and low mass transport resistance. The electric catalytic reduction peaks of dopamine on the PVA/a-MWCNTs hydrogel membrane-modified electrode is not affected by ascorbic acid in cyclic voltammetry test. Dopamine can be determined by the feature of the electrode membrane in the presence of excessive ascorbic acid. The linear interval of dopamine concentration was 2×10^-6—2×10^-3 mol/L, the threshold of detection concentration can reach 10^-6 mol/L and the sensitivity can reach 12.3 μA/(mmol·L^-1). The electrode membrane also has good stability for dopamine detection.



Theoretical Study on the Selective Redox Mechanism of Benzaldehyde in Photo-catalyzed Reaction^†

HUANG Xiao, GAN Hanlin, PENG Liang, GU Fenglong

2016, 37(2):  297-305.  doi:10.7503/cjcu20150719

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The photoelectron and photohole could be generated on the surface of TiO₂ under the UV irradiation. Some reactive species could be produced indirectly. The photoelectron could be trapped by oxygen leading to yield the superoxide anion radicals, while the photohole can react with the solvent molecules to generate the hydroxyl radical and alcohol radical. The substrate may be reduced by the photoelectron directly, or by alcohol radicals. And it may be oxidized by the photohole directly, or by the reactive species of hydroxyl radicals and superoxide anion radicals. The M06-2X/6-311G^* method was employed to investigate the selective redox mechanism of benzaldehyde in solution, which was reduced or oxidized by the reactive species generated during the photo-catalyzed process in different reaction conditions. According to the computation results, the photo-redox reaction of benzaldehyde would be happened in room temperature. In oxygen-free ethanol solvent, the ethanol molecules could react with the oxidizing species to yield the alcohol radicals, while benzaldehyde could be mainly reduced to benzyl alcohol. In oxygen-rich without ethanol condition, the reductive photoelectron is trapped by oxygen to prohibit the reduction of benzaldehyde, so benzaldehyde is mainly oxidized to benzoic acid.



Preparation and Lithium Ion Transport Behavior for Li_1.5Al_0.5Ge_1.5(PO₄)₃ Based Solid Composite Electrolyte

YU Tao, HAN Yu, WANG Hui, XIONG Shizhao, XIE Kai, GUO Qingpeng

2016, 37(2):  306-315.  doi:10.7503/cjcu20150704

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LAGP-PEO(LiTFSI) solid composite electrolyte were prepared with Li_1.5Al_0.5Ge_1.5(PO₄)₃(LAGP) and LiN(CF₃SO₂)₂(LiTFSI) as conductive components and poly(ethylene oxide)(PEO) as the binder using solution casting method. The molar ratio of EO/Li was 13 when the ratio of PEO to LAGP was varied. The role of LAGP and the transport mechanism of Li-ion in solid composite electrolyte were analyzed using electrochemical impedance spectroscopy and morphology techniques. The results showed that LAGP partially interacted to PEO(LiTFSI) and uniformly distributed in the electrolyte. With the increase of LAGP content, amorphous regions of PEO rises up to a maximum value due to the coordination interactions between LAGP and PEO(LiTFSI). Three phases are generally present, namely a pure crystalline LAGP phase, all amorphous complexion PEO(LiTFSI) phase and a transition phase consisting of lithium salt particles and amorphous PEO(LiTFSI). The electrochemical impedance spectroscopy(EIS) showed that Li⁺ ions can go through the interface between ceramic particles and polymer. Compared with other ceramic fillers(SiO₂, Al₂O₃), the addition of Li⁺conducting LAGP improves the ionic conductivity and electrochemical stability of PEO-based solid composite electrolyte. LAGP glass-ceramic improves solid composite electrolyte conductivity not only by enhancing the amorphous PEO phase, but also via its intrinsic conductivity. The highest ionic conductivity and the processability of LAGP-PEO(LiTFSI) solid electrolyte were obtained when the mass ratio of LAGP to PEO was fixed at 6:4. The optimal ionic conductivity can reach 2.57×10^-5 S/cm at room temperature which is close to that of LAGP. In addition, LAGP-PEO(LiTFSI) solid composite electrolyte shows an enlarged electrochemical stability window(>5 V) in comparison to the PEO(LiTFSI) polymer electrolyte. Solid composite electrolyte based on LAGP-PEO(LiX) has a great prospect in application due to the combination of the fast ion conductor LAGP with high ionic conductivity and the PEO-based polymer electrolyte with good processability.



Study on the Mechanism of Photocatalytic Degradation of Poly(α-olefin)^†

PENG Zhannan, LIU Xuefeng, LIN Guanqun

2016, 37(2):  316-321.  doi:10.7503/cjcu20150660

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Poly(α-olefin)(PAO, commonly used rolling base oil) attached to the surface of copper foil was degradated using photocatalytic microreactor. The chemical state, free radical and functional groups during the degradation process were detected by X-ray photoelectron spectroscopy(XPS), electron spin resonance spectroscopy(ESR) and Fourier transform infrared spectroscopy(FTIR). At last, the photocatalytic degradation mechanism was discussed. The results show that the introduction of oxygen groups and the CO₂ desorption exist in the degradation process and the main free radical is hydroxyl radical(·OH). The degradation process is accompanied with the increase of —OH and the decrease of C—H bond. In the process of photocatalytic degradation of PAO, ·OH attacking polymer is from the beginning of substitution reaction, firstly, ·OH substituted the hydrogen atom of methyl group, then the formed —OH changes to carboxyl and aldehyde, and then small organic molecules are formed. This process continues and the polymer molecular chain become shorter and shorter and produce only CO₂, H₂O and other inorganic substances at last.



Solar Thermal-electrochemical Synthesis of Benzoic Acid^†

ZHU Yanji, LIU Xuelin, WANG Huaiyuan, WANG Baohui

2016, 37(2):  322-327.  doi:10.7503/cjcu20150648

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Through solar thermal-electrochemical process(STEP) benzoic acid was synthesized by toluene oxidation. The synthesis of benzoic acid was totally driven by solar energy. Direct electro-oxidation behaviors of toluene were studied by cyclic voltammetry(CV) under constant electrolysis potential with three different anodes(platinum, nickel and graphite) in sulfuric acid and sodium dodecyl benzene sulfonate(SDBS). Results showed that the main product of toluene electro-oxidation in the sulfuric acid and surfactant SDBS was benzoic acid, which was detected by gas chromatography(GC), Fourier transform infrared spectroscopy(FTIR) and UV spectrophotometry(UV). The yield of benzoic acid could reach up to 51.6% from toluene by using graphite as anode in the sulfuric acid and surfactant system at 90 ℃ with STEP mode. A new green way of STEP for benzoic acid synthesis was provided.



Studies on the Calculation of Lennard-Jones Parameters for Intermediates in Hydrocarbon Combustion^†

SUN Yanjin, YAO Qian, LI Zerong, LI Juanqin, LI Xiangyuan

2016, 37(2):  328-334.  doi:10.7503/cjcu20150647

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Lennard-Jones(L-J) parameters were used in combustion modeling as transport parameters and in pressure-dependent rate-coefficient calculations as collision rate parameters. However, there are no reported values for most of the radical intermediates in hydrocarbon combustion. In this work, a new group contribution formula was proposed and group contribution values of 40 groups for intermediates in the combustion of hydrocarbons were fitted from critical properties of 250 species, including 185 stable species with experimental critical property values and 65 radical species with calculated critical property values and these group contribution values were used to estimate critical properties for new species. 30 hydrocarbon compounds with available experimental properties were chosen to validate the accuracy of the model, the average absolute deviation of T_C and P_C were 8.52% and 16.83%, respectively, showing an agreement with experimental data. This model can predict critical properties for macromolecular and radical species. According to the empirical relations between critical properties and L-J parameters, L-J parameters of hydrocarbon combustion intermediates were estimated. It was shown that the predicted values for 46 compounds with available reported data were in good agreement with the reported values and the average absolute deviation of T_C and P_C were 9.88% and 9.96%, respectively. The L-J parameters of alkane radical ^·C₆H₁₃, alkene radical ^·C₅H₉ and alkyne radical ^·C₅H₇ isomers were compared. L-J parameters of ^·C₆H₁₃ and similar compound C₆H₁₄ were also compared and the results showed that there were obvious differences of the L-J parameters between isomers or between similar compounds. In addition, L-J parameters for 114 hydrocarbon radicals, for which L-J parameters had not been reported yet, were predicted. These data are important in the combustion modeling of hydrocarbons and pressure-dependent rate-coefficient calculations for elementary reactions in hydrocarbon combustion.



Preparation of Composite Modified Expanded Graphite and Its Adsorption on Acid Brilliant Blue Dye^†

WANG Huili, ZHAO Yue, MA Lekuan, FAN Penghao, XU Congbin, JIAO Chunlei, LIN Aijun

2016, 37(2):  335-341.  doi:10.7503/cjcu20150544

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Modified expanded graphite(M-EG) was synthesized via same counter ion coordinated phosphate(H₃PO₄) activation method, as prepared expanded graphite(EG). M-EG was investigated by scanning electron microscopy(SEM), Fourier transform infrared spectroscopy(FTIR) and X-ray photoelectron spectroscopy(XPS). The adsorbent activities of the EG and M-EG were evaluated for the reduction of acid brilliant blue. The results indicated that the porosity of EG after composite modified expanded, the surface enlarged and the nitrogen- and bromine-containing functional groups increasing. Adsorbent M-EG in acid brilliant blue dye wastewater show high adsorbent activities with a 94.13% reduction at pH=1.0 and 30 ℃. The adsorption reaction of EG line with second-order kinetic adsorption model, and the Langmuir isotherm equation is well fitted; M-EG conform second adsorption kinetics equation, while compliance with Langmuir isotherm model and Freundlich isotherm model, what’s more adsorption kinetics constant is greater than EG’s.



Synthesis and Characterization of Intergrowth Structured SAPO-18/SAPO-34^†

ZHAO Dongpu, ZHAO Quansheng, ZHANG Yan, SHI Tuo, YAO Hengguo, YU Jianqiang

2016, 37(2):  342-348.  doi:10.7503/cjcu20150527

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SAPO-18(AEI structure) and SAPO-34(CHA structure) intergrowth structured silicoaluminophosphate molecular sieves were synthesized hydrothermally with trimethylamine(TEA) and N,N-diisopropylethylamine(DIEA) as double templates. Influencing factors, such as DIEA content, SiO₂/Al₂O₃ molar ratio and crystallization time were investigated in detail. The crystalline phase, morphology and acidic property of the products were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM) and temperature-programmed desorption of ammonia(NH₃-TPD), respectively. The results showed that well crystallized, morphology uniformed AEI/CHA intergrowth structured silicoaluminophosphate molecular sieves with AEI/CHA=74/26 could be synthesized under the following synthesis conditions: n(DIEA)/n(AEI)=0.2, n(SiO₂)/n(Al₂O₃)=0.6 and the crystallization time 96 h. The extending of crystallization time resulted in the disappearance of SAPO-5 and the gradual increase of AEI/CHA proportion. It is therefore concluded that the thermodynamic stability of SAPO-5, SAPO-34, SAPO-18 increased in this order. Dimethylether-to-olefins(DTO) reaction was chosen to test the catalytic performance of the prepared catalysts. The prepared catalyst using TEA-DIEA as double templates exhibited excellent catalytic performance in DTO(dimethyl ether to olefins) process. The conversion of dimethylether and selectivity of ethylene and propylene are up to 100% and 84.29%, respectively.



Heat Capacities and Ion-interaction of Lithium Tetraborate Aqueous Solution System^†

LI Long, ZHANG Sisi, LIU Yuanhui, GUO Yafei, DENG Tianlong

2016, 37(2):  349-353.  doi:10.7503/cjcu20150594

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The heat capacities of aqueous solution systems(Li₂B₄O₇-H₂O) with molality of Li₂B₄O₇ of 0.00415—0.4208 mol/kg at 298.15, 308.15 and 323.15 K were determined experimentally using microcalorimeter. On the basis of experimental data, the apparent molar heat capacities at different concentrations and temperatures were calculated, and the relationship equations between apparent molar heat capacity and solution concentration of lithium tetraborate at 298.15, 308.15 and 323.15 K were obtained. The Pitzer single salt parameters of lithium tetraborate at different temperatures were fitted based on the Pitzer ion-interaction theory on the apparent molar heat capacity of electrolytes.



Relationship Between Reversible Oxygenation and Catalytic Properties of Amino Acid Cobalt Complexes^†

WEI Yana, ZHANG Xincun, LI Hui, XU Qian, YUE Fan, WANG Jide

2016, 37(2):  354-360.  doi:10.7503/cjcu20150578

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The relationship between oxygenation properties and corresponding catalytic performance of 13 natural amino acid-cobalt(Ⅱ) complexes were identified. The results indicate that for those complexes with reversible oxygenation properties, the shorter the time spent for completing a reversible oxygenation cycle is, the better their reversible oxygenation and the worse the property of their catalysis are. As a contrast, longer cycle time for completing a reversible oxygenation cycle attest to worse performance of reversible oxygenation but better property of catalysis. In particular, the results of glutamic cobalt(Ⅱ) complexes confirms that when the ratio of Co(Ⅱ) and ligand is 1:3, the reversible oxygenation property is good, while the catalytic reaction yields a low conversion rate of cyclohexene. On the other hand, the complex with Co(Ⅱ):ligand 1:1 led to a high conversion rate of cyclohexene. With the help of the preliminary structural study and theoretical calculation, we suppose that the difference between reversible oxygenation property and catalytic property are mainly due to the coordinating ability of amino acid ligands. The strong coordinating ability of amino acid ligands is favorably to the high spin to low spin transform for reversibly absorbing O₂. While the less favorably for vinyl replacement exhibited poor catalytic properties, and vice versa.



Interaction Forces Between Simulated Mini Liquid Droplets of Emulsions^†

GUO Lanlei, LI Jing, ZHU Yangwen, MA Baodong, XU Zhicheng, WANG Wuning, ZHANG Lei, ZHANG Lu

2016, 37(2):  361-366.  doi:10.7503/cjcu20150455

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The interaction forces between liquid droplets were measured directly by reformed commercial DCAT21 tensiometer. The processes of approaching, squeezing and coalescence that occur between two liquid drops were observed and recorded by digital camera Digital 3.0. The experimental results indicate that the variation curves of interaction forces between mini droplets as a function of distance can provide the information of characteristic behavior of the dispersed droplets. The slopes of different stages of the curves can represent the magnitude of force and the squeezing distance before the coalescence can quantitatively reflect the stability of droplets. Different types of surfactants have different effects on hindering coalescence of two droplets and the nonionic surfactant TX-100 shows the better effect of stabilization. The coalescence of two droplets will be hindered by the layer structure formed by polymer molecules in thin liquid film. As a result, the force curves are step-shape.



Polymer Chemistry

Influence of Shear on i-Polypropylene Crystallization and Morphology^†

TANG Yujing, MEN Yongfeng

2016, 37(2):  367-372.  doi:10.7503/cjcu20150675

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The shear-induced crystallization behavior of isotactic polypropylene(iPP) was investigated by synchrotron small angle X-ray scattering, wide angle X-ray diffraction and differential scanning calorimetry. The results showed that the β-crystallinity were found after shearing and the total crystallnity kept almost constant. The β-crystallinity increased with the shear rate up to 10 s^-1 and then decreased at higher shear rates indicating the existence of competing processes of developing α- and β-crystallinities. At the shear rates between 10 s^-1 and 32 s^-1, two populations of long spacing were observed with the larger one attributed to the β-crystallinity.



Antimicrobial Adhesion and Anticorrosion Properties of Polypyrrole Film in Natural Seawater^†

MA Xiaodan, ZHANG Zhiming, YU Liangmin

2016, 37(2):  373-380.  doi:10.7503/cjcu20150627

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Polypyrrole was deposited on the surface of the 316L stainless steel electrode through galvanostatic method, and the antifouling property of the polypyrrole film in natural seawater was analyzed via open circuit potential, biological microscope, Tafel polarization curve and electrochemical impedance spectroscopy. It was found that the open circuit potential of the stainless steel electrode coated with polypyrrole was stable after 20 d of the immersion in the natural seawater, which indicates that the polypyrrole had a good ability to prevent the microorganism from attaching. This can be confirmed by the biological microscope. And the corrosion current density maintained at 10^-7 mA/cm² and showed good anticorrosion performance. The anticorrosion efficiency can still reach up 97.45% even the electrode is immersed in natural seawater for 50 d. Therefore, it could be concluded that the polypyrrole synthesized by electrochemical method exhibited good properties in the prevention of microbial attachment and good anticorrosion performance.



Synthesis and Properties of the Amino Acid Functionalized Curcumin/His-Pectin Colloidal Particles^†

YANG Zechuan, LI Fan, HUANG Qingrong, ZHANG Guo, SHI Tongfei

2016, 37(2):  381-387.  doi:10.7503/cjcu20150591

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New pH-responsive pectin derivatives were designed and synthesized by esterification. The architectures of the polymers were confirmed by Fourier transform infrared(FTIR) spectrophoto meter and Elemental analyses(EA). The prepared micelles properties were determined by UV-Vis spectra and transmission electron microscope(TEM). The cytotoxicity of Curcumin/His-Pectin colloidal particles was assessed using the cell counting kit-8 assay. The His-Pectin colloidal particles exhibited an irregular spherical shape from TEM photographs. Moreover, curcumin can be efficiently encapsulated in His-Pectin colloidal particles. The mean diameter of the curcumin colloidal particles was about 200 nm with narrow size distribution. The cytotoxic assays of Curcumin/His-Pectin colloidal particles demonstrated high inhibitory effect on HepG2 cell growth compared to the free curcumin. It was concluded that His-Pectin colloidal particles can efficiently encapsulate curcumin in vitro and promote the inhibition of HepG2 cell growth in vitro.



Fabrication of Patterned Polymer Membrane Through Replica Molding Technology Templated by Ordered Array from Continuous Meniscus^†

JIA Ruokun, YANG Xiaohang, LONG Zhiyun, HE Leiyin, WANG Panxin, ZHANG Lingyun, ZHAO Ming

2016, 37(2):  388-395.  doi:10.7503/cjcu20150545

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Replica molding technology has a reproducible and high-resolution advantage in fabrication of polymer patterns with the feature sizes of sub-micrometer to micrometer. It is critically desirable to develop a low cost and rapid route for building the initialtemplate. In this report, ordered array which could achieve morphological control was continuously supplied from solvent evaporation-driven process in a micron spacing gap by the coffee-stain theory. We use the patterned array as a mother setof the pattern definition of the soft moldpolydimethylsiloxane(PDMS) and obtain transferred patterns through replica molding technology. We also explore the polymer deposition periodically based on the theoretical model of Young-Laplace equation. The results demonstrate that the deposition frequency is influened by molecular weight of polymer, sliding speed of glass plate and concentration of solution. Trends predicted by these calculations agree with experimental behavior.



Preparation and Desalination Performance of Composite Reverse Osmosis Membrane Based on Electrospinning Technology^†

WANG Jiaona, YIN Zefang, LI Congju

2016, 37(2):  396-402.  doi:10.7503/cjcu20150519

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Electrospun polyethylene terephthalate(PET) nanofibrous membranes were prepared on the non-woven cloth, then crosslinked chitosan was coated on the composite membrane to modify it. Finally interfacial polymerization was conducted using m-phenylene diamine(MPD) and 1,3,5-benzenetricarbonyl trichloride(TMC) benzene as monomers on chitosan modified nanofibrous to prepare polyamide separation layer. A new type of nanofibrous composite reverse osmosis membrane was obtained. This composite reverse osmosis membrane has typical ridge and valley structure of the typical commercial polyamide composite reverse osmosis membrane. Sodium dodecyl benzene sulfonate(SDBS) content on the properties and structure of the membrane was systematically studied from three aspects, means the film surface morphology, hydrophilicity and separation properties. The results showed that the content of SDBS had a certain effect on the uniformity and hydrophilicity of the membrane morphology. In addition, with the increase of SDBS content, membrane desalination first increases then decreases, and the flux had a small amplitude increase,then it decrease after the increase.