Table of Content

01 October 2016, Volume 32 Issue 5

Previous Issue    Next Issue

Content

Chemical Research in Chinese Universities Vol.32 No.5 August 2016

2016, 32(5):  0-0. 

Abstract ( )   PDF (5058KB) ( )  

Related Articles | Metrics

Articles

A Novel Metal-organic Framework Using Heterometallic Tetranuclear Cluster as Secondary Building Block and Isophthalic Acid as Ligand

BAI Helong, ZHANG Daojun, ZHANG Renchun, WANG Junjie, ZENG Shuangli, FAN Yong, XU Jianing, ZHANG Ping

2016, 32(5):  709-712.  doi:10.1007/s40242-016-6221-4

Abstract ( )  

References | Related Articles | Metrics

A novel heterometallic-organic framework(HMOF), namely [ZnBa(1,3-BDC)₂(DMA)₂]_n(1)(DMA=N,N-dimethylacetamide), was synthesized by means of solvothermal method from isophthalic acid(1,3-BDC) ligand and relevant metal salts as raw materials. The single-crystal X-ray diffraction analysis result demonstrates that compound 1 is a three-dimensional(3D) framework including heterometallic tetranuclear[Zn₂Ba₂(COO)₈] clusters as building subunits, which could be simplified into an eight-connected body-centered cubic(bcu) topological net. At room temperature, compound 1 displays strong blue luminescence in solid state. Furthermore, the quantum yield and luminescent lifetime of compound 1 were also measured.



Multicolor Photoluminescence in ITQ-16 Zeolite Film

CHEN Yanli, DONG Xinglong, ZHANG Zhenyu, FENG Lai

2016, 32(5):  713-718.  doi:10.1007/s40242-016-6079-5

Abstract ( )  

References | Related Articles | Metrics

Exploring the native defects of zeolites is highly important for understanding the properties of zeolites, such as catalysis and optics. Here, ITQ-16 films were prepared via the secondary growth method in the presence of Ge atoms. Various intrinsic defects of ITQ-16 films were fully studied through photoluminescence and FTIR characterizations. It was found that both the as-synthesized and calcined ITQ-16 films displayed multicolor photoluminescence including ultraviolet, blue, green and red emissions by exciting upon appropriate wavelengths. The results indicate that Si-OH and non-bridging oxygen hole centers(NBOHCs) are responsible for the origin of green and red emissions at 540-800 nm, while according to a variety of emission bands of calcined ITQ-16 film, blue emission bands at around 446 and 462 nm are attributed to peroxy free radicals(≡SiO₂·), ultraviolet emissions ranging from 250 nm to 450 nm are suggested originating from a singlet-to-triplet transition of two-fold-coordinated Si and Ge, respectively.



Three Ni(Ⅱ) Coordination Polymers with Various Architectures Based on Asymmetric Bis-pyridyl-amide and Polycarboxylates: Syntheses, Structures and Properties

WU Xiaomei, LIU Guocheng, WANG Xiuli, SHAO Jiyan, LIN Hongyan, WANG Xiang

2016, 32(5):  719-724.  doi:10.1007/s40242-016-6072-z

Abstract ( )  

References | Related Articles | Metrics

Three different dimensional Ni(Ⅱ) coordination polymers,[Ni(3-pna)(HIP)(H₂O)₃]·H₂O(1),[Ni(3-pna)· (1,3,5-HBTC)](2) and [Ni₂(H₂O)(3-pna)₂(1,4-CHDC)₂]₄(3)(3-pna=3-pyridylnicotinamide, H₂HIP=5-hydroxyisoph-thalic acid, 1,3,5-H₃BTC=1,3,5-benzenetricarboxylic acid, 1,4-H₂CHDC=1,4-cyclohexanedicarboxylic acid), were synthesized under hydrothermal conditions and characterized by means of infrared spectra(IR), thermal gravimetric (TG) analyses, powder X-ray diffraction(PXRD) and single-crystal X-ray diffraction. Complex 1 has a structure of 1D single-stranded chain, which is further stretched by hydrogen-bond interactions to form a 2D supramolecular sheet. Complex 2 shows a 2D network, which is stretched to 3D supramolecular frameworks through hydrogen-bond interactions. Complex 3 reveals a 3D skeleton with a (3,3,6,6)-connected {3·7²}{3²·4}{3³·4²·5·7³·8⁵·9}{3³·4⁵·5²·7²·8²·9} topology. The effects of different polycarboxylates on the ultimate architectures of the complexes 1-3 were discussed. Furthermore, the fluorescent and photocatalytic properties of the title complexes were also investigated.



A Dual Read-out Molecularly Imprinted Composite Membrane Sensor Based on Zinc Porphyrin for the Detection of Dimethyl Methylphosphonate

ZHANG Ya, QIAN Linlin, YIN Wei, HE Bin, LIU Fangmei, HOU Changjun, HUO Danqun, FA Huanbao

2016, 32(5):  725-730.  doi:10.1007/s40242-016-6120-8

Abstract ( )  

References | Related Articles | Metrics

Molecularly imprinted membrane-zinc porphyrin-mathacrylate(MIM-Zn-MAA), a dual read-out sensor based on a molecularly imprinted membrane, was developed to recognize and detect dimethyl methylphosphonate (DMMP) as an intermediate molecule of organophosphorus pesticides. The membranes were prepared via thermal polymerization of two functional monomers(zinc porphyrin and mathacrylate) on the surface of a glass slide functionalized with ethylene glycol dimethacrylate and azobisisobutyronitrile. The morphology of the as-synthesized MIM-Zn-MAA was determined with scanning electronic microscopy. The composite membranes exhibited macrovoid morphologies, which were affected by the functional monomers. These membranes were selectively adsorbed onto the template molecule and displayed higher adsorbing capacity toward DMMP compared with their structural analogs. Changes in the fluorescent spectra were qualitatively and quantitatively monitored via fluorescence photometry. Difference maps were also obtained using colorimetry before and after the reaction between MIM-Zn-MAA and DMMP at various concentrations. The maps showed a wide linear range varying from 0.1 μmol/L to 10 mmol/L with a low detection limit of 0.1 μmol/L. These preliminary results demonstrate that the as-fabricated dual read-out sensor displays good sensitivity and selectivity toward DMMP, indicating its considerable potential in DMMP detection in practical applications.



Simultaneous Determination of Oil and Water in Soybean by LF-NMR Relaxometry and Chemometrics

WU Jing, LI Yanru, GAO Xingsheng

2016, 32(5):  731-735.  doi:10.1007/s40242-016-6096-4

Abstract ( )  

References | Related Articles | Metrics

A fast, non-destructive and eco-friendly method was developed to simultaneously determine the oil and water contents of soybean based on low field nuclear magnetic resonance(LF-NMR) relaxometry combined with chemometrics, such as partial least squares regression(PLSR). The Carr-Purcell-Meiboom-Gill(CPMG) magnetization decay data of ten soybean samples were acquired by LF-NMR and directly applied to the PLSR analysis. Calibration models were established via PLSR with full cross-validation based on the reference values obtained by the Soxhlet extraction method for measuring oil and oven-drying method for measuring water. The results indicate that the calibration models are satisfactory for both oil and water determinations; the root mean squared errors of cross-validation(RMSECV) for oil and water are 0.2285% and 0.0178%, respectively. Furthermore, the oil and water contents in unknown soybean samples were predicted by the PLSR models and the results were compared with the reference values. The relative errors of the predicted oil and water contents were in ranges of 1.25%-4.96% and 0.44%-2.49%, respectively. These results demonstrate that the combination of LF-NMR relaxometry with chemometrics shows great potential for the simultaneous determination of contents of oil and water in soybean with high accuracy.



A Selective and Sensitive Fluorescence Probe for Se(Ⅳ) Based on Fluorescence Quenching of Gatifloxacin

LIU Qing, HUAN Yanfu, ZHENG Qingchuan, FEI Qiang, FEI Yanqun, FAN Qian, FENG Guodong, SHAN Hongyan

2016, 32(5):  736-741.  doi:10.1007/s40242-016-6015-8

Abstract ( )  

References | Related Articles | Metrics

A novel high selective and sensitive fluorescence probe termed gatifloxacin was discovered based on fluorescence "on-off" phenomenon in the presence of Se(Ⅳ). In the Tris-HCl/acetonitrile(3:7, volume ratio, Tris-HCl 0.05 mol/L, pH=7.3) sys-tem, the fluorescence intensity of gatifloxacin was linearly decreased with the concentration increase of Se(Ⅳ) in a range of 1.0×10^-5-5.0×10^-5 mol/L with a correlation coefficient of 0.9979(R²=0.9958) and in a range of 5.0×10^-5-1.0×10^-4 mol/L with a correlation coefficient of 0.9973(R²=0.9946). The detection limit of Se(Ⅳ) was 1.70×10^-6 mol/L.



A Fluorescent and Colorimetric Probe Based on Isatin-appended Rhodamine for the Detection of Hg²⁺

CHEN Jiayi, SHU Wei, WANG Enju

2016, 32(5):  742-745.  doi:10.1007/s40242-016-6001-1

Abstract ( )  

References | Related Articles | Metrics

A new fluorescent probe for the detection of Hg²⁺ was designed and synthesized via attaching N-methylisatin to rhodamine B hydrazide through an imine linkage. In an ethanol-Tris buffer medium, the addition of Hg²⁺ caused a strong orange fluorescence and a visual color change from colorless to pink. Other coexisting metal ions did not interfere with the detection of Hg²⁺. The research on the detection of Hg²⁺ in natural water suggested the possibility of practical applications in environment monitoring. Based on ESI-MS analysis, the Hg²⁺-sensing mechanism was proposed.



Source Apportionment Research of Fine Particulate Matter in the Atmosphere by PAHs

WANG Ju, YANG Le, MA Tianyi, SUN Liyuan, YU Liangui, FANG Chunsheng

2016, 32(5):  746-753.  doi:10.1007/s40242-016-5516-9

Abstract ( )  

References | Related Articles | Metrics

Haze weather frequently occurs in many cities in China. Polycyclic aromatic hydrocarbons(PAHs) in fine particulate matter(PM_2.5) can adversely affect the environment and human health. In this paper, PM_2.5 samples were collected at nine sites in a city in northeastern China from September 2013 to October 2014. Sixteen USEPA(US Evironment Protection Agency) priority PAHs in PM_2.5 were analyzed to determine their spatial and temporal distribution characteristics. The source apportionment of PAHs was conducted with the Positive Matrix Factorization(PMF) model. The results indicate that the concentrations of total PAHs(T-PAHs) in PM_2.5 are within the range of 0.26 to 72.48 ng/m³. The seasonal variation of T-PAHs is winter >spring >autumn >summer, and the space distribution of PAHs is JZP >DP >BFH >LP >EESA >IPT >CP >HZMC >JYP. In all types of PAHs, three-ring and five-ring PAHs are significantly prominent(62%) in the heating period due to petrogenic sources and traffic emissions. Middle- and high-ring PAHs in the non-heating period are caused by coal combustion and vehicle exhaust, which accounts for 77% of the total emissions. The source apportionment results obtained by the diagnostic ratio of PAHs reflect that coal burning, traffic and other sources have a distinct influence on PAH emissions in this city. Six factors are defined by PMF v5.0, namely, coke oven emissions(7.7%), biomass burning(44.3%), petrogenic sources(10.7%), coal combustion(10.4%), gasoline engine emissions(16.7%), and diesel engine emissions(10.3%). The results indicate that the PAHs in PM_2.5 in the city are primarily caused by combustion processes and vehicle exhaust.



Synthesis of Aminoalkyl-substituted Polymethoxychalcone Derivatives and Their Antiproliferative Activities Against Three Human Cancer Cell Lines

CHEN Mingxia, SHI Ling, TANG Jiaqing, WANG Qiuan

2016, 32(5):  754-759.  doi:10.1007/s40242-016-6190-7

Abstract ( )  

References | Related Articles | Metrics

Two novel series of sixteen aminoalkyl-substituted polymethoxychalcone derivatives 2a-2h and 3a-3h were synthesized from 2'-hydroxy-3,4,5,4',6'-pentamethoxy chalcone(1) through extending alkoxy side chain at the 2'-position, and introducing amine hydrogen bond receptor at the end of the side chain. The structures of all the synthesized compounds were confirmed by ¹H NMR, ¹³C NMR and MS techniques. Furthermore, all the compounds were tested for antiproliferative activities in vitro against a panel of three human cell lines(HeLa, HCC1954 and SK-OV-3) via CCK-8 assay. The results show that all the target compounds exhibit antiproliferative activities against the three human cancer cells with IC₅₀ values of 4.62-48.21 μmol/L, except compound 2h against SK-OV-3 cells. Most of these compounds were more active when compared to the positive control cis-Platin.



Synthesis and Biological Evaluation of Amino Alcohol Containing 1,3,4-Oxadiazole

WU Yi, ZHAO Yanping, GUO Jing, LÜ Haoze, ZHENG Nan, WANG Ensi

2016, 32(5):  760-767.  doi:10.1007/s40242-016-6164-9

Abstract ( )  

References | Related Articles | Metrics

A series of amino alcohol derivatives containing 1,3,4-oxadiazole moieties was synthesized with 7-bromo-2-tetralone as starting materials, 2,2-dimethyl-1,3-oxazolidine as intermediates and Strecker reaction and cyclization with POCl₃ as key steps. The structures of the key intermediate and target compounds were confirmed by ¹H NMR, ¹³C NMR and HRMS. Some compounds have resulted in the generation of highly potent sphingosine 1-phosphate receptor type 1(S1P₁) agonists.



Improved Antiproliferative Activities of a New Series of 1,3,4-Thiadiazole Derivatives Against Human Leukemia and Breast Cancer Cell Lines

LIU Tingting, WAN Yichao, LIU Renshuai, MA Lin, LI Minyong, FANG Hao

2016, 32(5):  768-774.  doi:10.1007/s40242-016-6159-6

Abstract ( )  

References | Related Articles | Metrics

Twenty-two novel 1,3,4-thiadiazole derivatives were synthesized using different aromatic acids as starting materials, followed by cyclization, coupling and deprotection reaction. The structures of all the target compounds were identified by means of ¹H nuclear magnetic resonance(NMR), ¹³C NMR and high resolution mass spectrometer(HRMS). Further biological evaluations were performed for chronic myelogenous leukemia cell and breast cancer cell. The results suggest that most of the target compounds exhibit potent anti-proliferative activities. Especially, compound 5b shows better antiproliferative activities against MDA-MB-231 and K562 cell lines compared with gossypol.



Photolysis and Cycloaddition Reactivity of Diferrocenyl Substituted Cyclopentadienone

ZHANG Xiaoyong, HAN Limin, GAO Yuanyuan, SHI Jiale, SUO Quanling

2016, 32(5):  775-780.  doi:10.1007/s40242-016-6158-7

Abstract ( )  

References | Related Articles | Metrics

The photolysis results of new diferrocenyl substituted cyclopentadienone(3) show that sunlight and air play an important role in the decomposition of compound 3, and two new compounds, 2-cyclopentenone(4) and α-pyrone(5), were obtained via photolysis of compound 3. The photolysis process was investigated by ¹H NMR, and a plausible mechanism for the formation of compound 5 was deduced. The cycloaddition reactions of substituted cyclopentadienones(3, 7, 9) with maleimide gave substituted imides 8, 10, 11, 12 and an unprecedented diferrocenyl substituted 1H-pyrrol-3(2H)-one derivative 13, respectively. The structures of compounds 4, 5, 8, 10, 11, 12 and 13 were confirmed by X-ray single crystal diffraction analysis technique.



Syntheses and Fungicidal Activities of Thiazole-5-carboxanilides Bearing Thioether Group

XUE Hansong, LIU Aiping, LIU Weidong, LI Jianming, REN Yeguo, HUANG Lu, HE Lian, OU Xiaoming, YE Jiao, HUANG Mingzhi

2016, 32(5):  781-785.  doi:10.1007/s40242-016-6153-z

Abstract ( )  

References | Related Articles | Metrics

In an attempt to find leading thiazole carboxanilides exhibiting fungicidal activities, we designed and synthesized a new series of 2-sulfursubstituted thiazole carboxanilides via the reaction between 2-sulfur substituted thiazole carboxylic acid chlorides and substituted aniline. The fungicidal activities of the title compounds against Rhizoctonia solani were screened and the results were remarkable. The most potent compound 8i, N-[2,6-dichloro-4-(trifluoromethyl)phenyl]-2-methylthio-4-(trifluoromethyl)thiazole-5-carboxamide, was identified. The fungicidal EC₅₀ of compound 8i against Rhizoctonia solani was 1.28 mg/L, being comparable to that of Thifluzamide. The results indicate that compound 8i can be considered as a lead compound for further research.



An Expedient Method for Regioselective Methylation of Catechol Coumarins

LU Junxia, WANG Ping, HOU Jie, ZOU Liwei, CUI Pan, YANG Ling, GE Guangbo, GONG Xiaojie

2016, 32(5):  786-791.  doi:10.1007/s40242-016-6147-x

Abstract ( )  

References | Related Articles | Metrics

An expedient and efficient method for selective methylation of catechol coumarins by working with different alkalis under appropriate reaction conditions was reported. Esculetins were selectively methylated at position 6 and position 7 in good yields using CH₃I in the presence of NaH and Na₂CO₃, respectively. However, daphnetins showed less regioselectivity under the same reaction conditions. Furthermore, the site preference for the methylation reaction was interpreted by the density functional theory at B3LYP/6-31+G(d) level.



Isolation and Stucture Elucidation of Diterpenes from Wedelia prostrata and Their Cytotoxicity Activities

CHEN Qing, LIN Jianhong, ZHAO Dan, ZHU Xuan

2016, 32(5):  792-796.  doi:10.1007/s40242-016-6122-6

Abstract ( )  

References | Related Articles | Metrics

In this paper, a new diterpene together with seven known diterpenes was isolated from Wedelia prostrata. The chemical structure of the new compound was elucidated via 1D and 2D nuclear magnetic resonance(NMR) techniques and mass spectrometry and identified to be 3α-phenylpropionoyloxy-ent-kaur-16-en-oic acid(1). The isolated diterpenes were tested for their cytotoxicity activities via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay. The results show that compounds 1, 2, 3, 4 and 6 exhibit different levels of cytotoxic activities. Especially, compound 2 shows significant cytotoxicity toward HeLa and A549 cell lines(IC₅₀=6.14 and 8.76 μmol/L).



Ultrafast Manipulation of Transient Energy Transfer Between Surface Plasmons and Resonators in Hybrid Nano-coupling System

YUE Yuanyuan, ZHANG Zhenyu, WANG Haiyu

2016, 32(5):  797-802.  doi:10.1007/s40242-015-6208-1

Abstract ( )  

References | Related Articles | Metrics

Surface-plasmon(SP) modes triggered on metal nanostructures were strongly coupled to the local restricted electronmagnetic field supported by a Fabry-Perot(F-P) cavity. This hybrid system provided an ideal platform to study the interaction between SP and F-P resonators on nanoscales. However, the time-resolved transient energy transfer process is far from resolved. In this letter, we addressed this question by time-resolved femtosecond pump-probe technology and readily observed the transient energy transfer between SP and nanocavity resonant energy. The interaction resulted in the emergence of hybrid splitting mode and the oscillating dynamics between upper and lower polariton branch(the split hybrid states). Our work may provide a well comprehension of strong coupling between SP modes and F-P resonator modes, and lay some groundwork for many future photonic applications.



Collision Dynamics of an Energetic Carbon Ion Impinging on the Stone-Wales Defect in a Single-walled Carbon Nanotube

ZHANG Chao, MAO Fei, MENG Xiangrui, PAN Chengling, SHENG Shaoding

2016, 32(5):  803-807.  doi:10.1007/s40242-016-6179-2

Abstract ( )  

References | Related Articles | Metrics

By employing atomistic simulations based on an empirical potential model and a self-consistent-charge density-functional tight-binding method, the collision dynamics process of an energetic carbon ion impinging on the Stone-Wales defect in a single-walled carbon nanotube was investigated. The outwardly and inwardly displacement threshold energies for the primary knock-on atom in the Stone-Wales defect were calculated to be 24.0 and 25.0 eV, respectively. The final defect configuration for each case was a 5-1DB-T(DB=dangling bond) defect formed in the front surface of the nanotube. Moreover, the minimum incident energy of the projectile prompting the primary knock-on atom displacement was predicted to be 71.0 eV, and the time evolutions of the kinetic and potential energies of the projectile and the primary knock-on atom were both plotted to analyze the energy transfer process.



Effect of Structural Properties of Mesoporous Co₃O₄ Catalysts on Methane Combustion

JIA Yongchang, WANG Shuyuan, LU Jiqing, LUO Mengfei

2016, 32(5):  808-811.  doi:10.1007/s40242-016-6141-3

Abstract ( )  

References | Related Articles | Metrics

Highly ordered 2D and 3D-Co₃O₄ catalysts were prepared using SBA-15 and KIT-6 as templates. Nano-Co₃O₄ catalyst was obtained by calcination of cobalt nitrate as a comparison. The BET surface area of nano-Co₃O₄, 2D-Co₃O₄ and 3D-Co₃O₄ catalysts was 16.2, 63.9 and 75.1 m²/g, respectively. All the catalysts were tested for the total combustion of methane and their catalytic performance was in the order of 3D-Co₃O₄(T₉₀=355℃) >2D-Co₃O₄(T₉₀=383℃) >nano-Co₃O₄(T₉₀=455℃). It was also found that the order of the areal specific reaction rates for the combustion of methane followed the same order of total activity. The characterization result demonstrates that enhanced catalytic performance of methane of the 2D-Co₃O₄ and 3D-Co₃O₄ catalysts is due to their pronounced reducibility and abundant active Co3+ species, which was caused by the preferential exposure of {220} crystal planes in 3D-Co₃O₄ and 2D-Co₃O₄ catalysts compared to the nano-Co₃O₄.



Three New Compounds Based on 4,4'-Azo-1,2,4-triazol-5-one: Synthesis, Crystal Structure and Thermal Properties

GUO Jiajia, HUANG Jie, SONG Jirong, MIAO Kanghua, CAO Wenli

2016, 32(5):  812-817.  doi:10.1007/s40242-016-6114-6

Abstract ( )  

References | Related Articles | Metrics

A series of guanidine salts of 4,4'-azo-1,2,4-triazol-5-one with guanidine(1), aminoguanidine(2), diaminoguanidine(3) and triaminoguanidine(4) was prepared. Compounds 2-4 were characterized by infrared(IR) spectroscopy, elemental analysis and single-crystal X-ray diffraction. Thermal decomposition processes of compounds 1-4 were investigated by differential scanning calorimetry(DSC), and all the compounds showed good thermal stability up to 190℃. Moreover, these four guanidine salts are more unstable with the increasing number of amino groups. Thermal stability parameters(T_e,0 and T_b) and thermodynamic functions(ΔS^≠, ΔH^≠ and ΔG^≠) for compounds 1-4 were calculated. The constant-volume combustion heats(Δ_cU) for compounds 2-4 were determined and tended to increase with the increase of the number of amino groups. The calculated standard molar enthalpies of formation(Δ_fH⁰m) of compounds 2-4 are -541.04, -178.67 and -83.08 kJ/mol, respectively. The impact sensitivities results indicate that these four energetic salts are less sensitive than 1,3,5-trinitrotriazacyccohexane(RDX) and 1,3,5,7-tetranitrotetraqza-cyclo-octane(HMX).



Free Rotor Model or Rigid Rotor Model for CH₃F-Ne Complex and Comparison with Other CH₃F-Rare Gas Systems

MA Yongtao, ZHAO Yuanyuan, HOU Dan, LI Hui

2016, 32(5):  818-826.  doi:10.1007/s40242-016-6109-3

Abstract ( )  

References | Related Articles | Metrics

The assignment of the rovibrational spectra of molecule-Ne complexes is always a challenge to study van der Waals systems, since they usually exhibit behavior intermediate between free rotor and rigid rotor. In this paper, the microwave and infrared spectra of CH₃F-Ne, a model system for symmetric-top-atom dimer, were firstly predicted and analyzed based on the four-dimensional ab initio intermolecular potential energy surfaces(PESs), which explicitly incorporate the v₃(C-F) stretch normal model coordinate of the CH₃F monomer. Analytic three-dimensional PESs were obtained by least-squares fitting vibrationally averaged interaction energies for v₃(CH₃F)=0 and 1 to the Morse/long-range(MLR) potential function for symmetry top impurity with atom model. These PESs fitting to 2340 points have root-mean-square(RMS) deviations of 0.07 cm^-1, and require only 167 parameters. Based on the analytical vibrationally averaged PESs, the rovibrational energy levels were calculated by employing Lanczos algorithm, with combined radial discrete variable representation and parity-adapted angular finite basis representation. Based on the wavefunction analysis and comparison of CH₃F-Ne with CH₃F-He and CH₃F-Ar complexes, the bound states were assigned. Spectral parameters for CH₃F-Rg(Rg:rare gas, Rg=He, Ne, Ar) complexes were fitted and discussed. Temperature dependent transition intensities for CH₃F-Ne were also reported and analyzed. The complete microwave and infrared spectra information for CH₃F-Ne made it possible to provide important guidance for future experimental spectroscopic assignments.



Electrochemical and Quantum Chemical Studies of Azoles as Corrosion Inhibitors for Mild Steel in Hydrochloric Acid

ZHANG Weiwei, MA Rui, LI Shuai, LIU Yu, NIU Lin

2016, 32(5):  827-837.  doi:10.1007/s40242-016-6084-8

Abstract ( )  

References | Related Articles | Metrics

The inhibition effect of three azole compounds, 2-aminobenzimidazole(ABM), 2-aminothiazole(AT) and 2-aminobenzothiazole(ABT), on the corrosion of mild steel in a 1 mol/L HCl solution was investigated by means of potentiodynamic polarization measurement, electrochemical impedance spectroscopy(EIS) and scanning electron mi-croscopy(SEM). The correlation between inhibition efficiency and molecular structure of inhibitor was theoretically studied via quantum chemical calculations. The results show that the inhibition efficiency(η) of the inhibitors follows the order of η_ABT >η_AT >η_ABM. Moreover, ABM, AT and ABT belong to mixed-type inhibitors. The adsorption of the inhibitors on the steel surface follows the Langmuir adsorption isotherm, with both physisorption and chemisorption.



Basic Catalytic Performance of Amino and Acylamide Functionalized Metal-organic Framework in the Synthesis of Chloropropene Carbonate from CO₂ Under Atmospheric Pressure

SONG Lili, CHEN Chao, CHEN Xiangbin, ZHANG Ning

2016, 32(5):  838-842.  doi:10.1007/s40242-016-6076-8

Abstract ( )  

References | Related Articles | Metrics

In this work, a metal-organic framework with free standing basic groups(e. g., amino and acylamide groups) decorated in the pore wall was utilized to catalyze the CO₂ cycloaddition reaction and its basic properties were tested in Knoevenagel condensation reactions. The results reveal that the metal-organic framework(MOF) material has excellent catalytic activity and high repeatability for the synthesis of chloropropene carbonate from CO₂ and epichlorohydrin with no co-catalyst under mild reaction conditions, suggesting that it is a promising heteroge-neous catalyst for CO₂ cycloaddition reaction.



Size Controlling Preparation, Adsorption and Catalytic Properties of Silica Microspheres

GUO Tianyu, DU Jianping, WANG Shuang, WU Jinting, LI Jinping

2016, 32(5):  843-847.  doi:10.1007/s40242-016-5492-0

Abstract ( )  

References | Related Articles | Metrics

The size-controlled silica microspheres were prepared by a facile method and the growth mechanism was simply studied. The as-prepared samples were characterized by scanning electron microscopy and transmission electron microscopy. The CO₂ adsorption behaviors and methane catalytic oxidation were also measured. The results show that the as-prepared silica is perfect sphere, and the particle size can be controlled by adding tartaric acid. Spherical silica and sphere/tube(rod)-shaped silica were obtained by adjusting reaction time. Silica microspheres with uniform size exhibit high capacity of CO₂ adsorption, while others with wide size-distribution exhibit excellent catalytic performance, suggesting it is an effective method by regulating size to utilize its advantages selectively. Therefore, it will be an ideal strategy to develop the efficient multifunctional materials by a facile route.



Effects of the Molecular Weight of PLGA on Degradation and Drug Release In vitro from an mPEG-PLGA Nanocarrier

LIU Rui, WANG Yan, MA Yudan, WU Yi, GUO Yi, XU Li

2016, 32(5):  848-853.  doi:10.1007/s40242-016-6155-x

Abstract ( )  

References | Related Articles | Metrics

We successfully synthesized four kinds of copolymers with varying molecular weights of poly(lactide-co-glycolide)(PLGA) to yield methoxy-poly(ethylene glycol)-block-poly(lactide-co-glycolide)(mPEG-PLGA) nanocarriers:mPEG-PLGA(3k), mPEG-PLGA(9k), mPEG-PLGA(11k) and mPEG-PLGA(16k). An antitumor drug, 10-hydroxycamptothecin(HCPT), was encapsulated into the mPEG-PLGA nanocarrier cores by self-assembly in dialysis. The lower molecular weight nanocarriers degraded more quickly, resulting in mass loss, pH decline, and a rapid HCPT release rate in vitro. The degradation and drug release of the nanocarriers were dependent on the PLGA molecular weight. However, the larger molecular weight nanocarriers could not increase the loading content and encapsulation efficiency. Considering the antitumor effect of these nanocarriers, the mPEG-PLGA(9k) nanocarrier, which had the highest drug loading content[(7.72±0.57)%] and a relatively high encapsulation efficiency[(22.71±5.53)%], is an optimum agent for drug delivery.



Fabrication and Photocatalytic Properties of Water-stable Ag/PW₁₂/PVA Nanocomposites

SUI Chunhong, WANG Zhaoyi, WANG Cheng, ZHOU Guangdong, CHENG Tiexin

2016, 32(5):  854-861.  doi:10.1007/s40242-016-6088-4

Abstract ( )  

References | Related Articles | Metrics

A kind of water-stable phosphotungstic acid/polyvinyl alcohol(PW₁₂/PVA) fiber was prepared by thermal or chemical crosslinking treatments with the help of electrospinning, and silver nanoparticles(NPs) modified fibrous precursor was successfully obtained by photoreduced method. The nanocomposites were characterized by transformation infrared spectroscopy(FTIR), UV-Vis diffuse reflection spectroscopy(DRS), field environmental scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM) and X-ray photoelectron spectroscopy(XPS). The results indicate that the sizes of silver NPs are about 20 or 40 nm on thermally or glutaraldehyde(GA) vapor crosslinked PW₁₂/PVA fiber, respectively. As a photocatalyst, PW₁₂/PVA fiber possesses high surface area to volume ratio, stable recyclability, and efficient transportation of electrons under visible light. The nanohybrids exhibit excellent photocatalytic activity for the degradation of Rhodamin B than PW₁₂/PVA nanofiber.



Preparation of Single-handed Helical and C-Shaped 3-Aminophenol-formaldehyde Resin Nanotubes and Single-handed Helical Carbonaceous Nanotubes

CAO Yanfang, LIU Dan, LI Baozong, LI Yi, YANG Yonggang

2016, 32(5):  862-866.  doi:10.1007/s40242-016-6069-7

Abstract ( )  

References | Related Articles | Metrics

Single-handed helical and C-shaped 3-aminophenol-formaldehyde resin nanotubes were prepared via a supramolecular templating approach. The chiral templates and 3-aminophenol were initially organized into helical nanoribbons, followed by the adsorption of formaldehyde onto the surfaces of the helical nanoribbons. Subsequent to polymerization and further thermosetting of the resin oligomers, 3-aminophenol-formaldehyde resin nanotubes were obtained after removing the templates. When low amounts of 3-aminophenol were added, straight C-shaped 3-aminophenol-formaldehyde resin nanotubes were obtained. Increasing the amount of added 3-aminophenol led to the formation of single-handed helical nanotubes instead. When the single-handed helical resin nanotubes were carbonized at 900℃ under Ar, single-handed helical carbonaceous nanotubes were obtained. Raman spectrum indicates that this carbon is predominantly amorphous. Circular dichroism spectra illustrate that both the helical resin nanotubes and the carbonaceous nanotubes exhibit optical activity. This work indicates that the added amount and the edge-adsorption mode of the precursors on the templates determine the final morphology and chirality of the products.



Effect of Surface-modified Clay on the Thermal Stability and Insulation of Polyorganosiloxane Foam

ZHANG Chunling, HUANG Rong, HOU Jiazi, LI Aiming, HOU Xiaoman, GU Xiaoyan

2016, 32(5):  867-871.  doi:10.1007/s40242-016-6002-0

Abstract ( )  

References | Related Articles | Metrics

Polyorganosiloxane foam(SIF) nanocomposites reinforced with vinyl-modified montmorillonite(Mt-V) and hydrox-yl-modified montmorillonite(Mt-OH) were prepared through cross-linking and foaming. The effects of modified Mt on the density, pore morphology, and thermal and compressive properties of the prepared polyorganosiloxane foams were investi-gated. The structure of the polyorganosiloxane foam was studied by solid-state nuclear magnetic resonance analysis. Clay dispersion in polyorganosiloxane nanocomposites and pore morphology were investigated by X-ray diffraction and scan-ning electron microscopy analyses. The thermal and mechanical properties of the prepared materials were also evaluated by differential scanning calorimeter, thermogravimetric analysis, thermal diffusivity and compressive strength. The results show that Mt-V exhibits improved cell structure, thermal insulation, and crush compressive than Mt-OH. The addition of modified Mt reduces the density, cell size, and thermal conductivity but increases the high-temperature resistance and com-pressive strength of the nanocomposite. The amount of the residues of SIF/Mt-OH nanocomposites increases by 9% com-pared with that of the pure SIF. Furthermore, SIF/Mt-V decreases the thermal conductivity to 0.014 W/mK and the cell size to 98 μm. Those properties give the material potential application value in the aerospace and construction industry.



Hybrid Hydrogels Assembled from Phenylalanine Derivatives and Agarose with Enhanced Mechanical Strength

YU Ye, WANG Yuxiang, FENG Chuanliang

2016, 32(5):  872-876.  doi:10.1007/s40242-016-5474-2

Abstract ( )  

References | Related Articles | Metrics

A roadblock for supramolecular hydrogels is their poor mechanical properties. Herein, to enhance the mechanical strength of supramolecular hydrogels, agarose(AG) was incorporated into the low molecular weight hydrogelator(G1). The results of scanning electron microscopy(SEM), circular dichroism(CD) and Fourier transform infrared spectroscopy(FTIR) prove that G1 gelators can self-assemble into cross-linked network together with AG. The mechanical properties of the gels are characterized by a rotary rheometer and the mechanical properties of the hybrid hydrogels(Hgel) can be significantly improved and may be further tuned by changing the ratio of the two components. For example, the elastic modulus of Hgel Ⅱ[m(G1):m(AG)=7:3] is about 2 times higher than that of G1 hydrogel. The results demonstrate that the mechanical property of hybrid supramolecular hydrogels can be adjusted through the formation of a cross-linked network.