查找使用阿拉丁产品的科研文献

5, 10, 15, 20-tetrakis-(4-methoxyphenyl) porphyrin film/K+ ion-exchanged optical waveguide gas sensor

Gulgina Mamtmin,Nuerguli Kari,Renagul Abdurahman,Patima Nizamidin,Abliz Yimit

Optical waveguide (OWG) sensors are widely used in gas detection, and sensitive materials are the key factors affecting sensor performance. Herein, we report on a 5,10,15,20-tetrakis-(4-methoxyphenyl) porphyrin (TMP) deposited optical wave guide (OWG) sensor. The porphyrin solutions with different acidity were deposited on a K + -ion exchanged glass OWG surface by spin coating, to fabricate porphyrin film-coated OWG gas sensing devices. The effects of pH values of the porphyrin solution used to prepare the sensitive film on the sensing properties of these devices were investigated. The gas sensitive performances of these devices in response to analytes were compared. Among them, the sensing devices fabricated using original and acidic solutions of porphyrin exhibited significant responses to sulfide gases and ethanediamine, respectively. The sensing device prepared using an acidic solution has a good response to ethanediamine gas (response and recovery times of the sensor for 1 ppm of EDA (ΔI = 48) are 13 and 38 s, respectively). The RSD of the output light intensity is ±2.84, the signal to noise ratio (S/N) is 5.6. The device prepared using the original solution has an excellent response to sulfide gases (H 2 S, SO 2 ), and can detect low concentration levels (ppm) of sulfide gases. These sensing devices thus have the potential to be used in food quality testing and environmental monitoring.

Phase Equilibrium and Phase Diagram for the Quaternary System LiBr–NaBr–KBr–H2O at 298.15 K

Rui-Zhi Cui,Wu Li,Ya-Ping Dong,Jun Li

The solubilities in the thermodynamic phase equilibria of the LiBr–NaBr–KBr–H2O system and its two subsystems LiBr–NaBr–H2O and LiBr–KBr–H2O at 298.15 K were investigated experimentally by the isothermal solution equilibrium method. Relevant stable-phase diagrams were plotted based on the experimental results. Using Pitzer’s solution model, nonreported mixing parameters ΨLi,Na,Br and ΨLi,K,Br were acquired and the solubilities of three systems were also predicted at 298.15 K. The results show that good agreement was obtained between calculated and experimental values.

Liquid-liquid equilibrium for ternary systems of 2,2,2-trifluoroethanol, water and different extractants at 303.2 K

Mai Han,Yuanyuan Han,Houchun Yan,Huanhuan Gui,Weizhen Sun,Qingsong Li

2,2,2-trifluoroethanol (TFE) is used more and more widely in industry, but there are few reports on its separation at present. The purpose of this work is to explore the feasibility of separating 2,2,2-trifluoroethanol from aqueous solution using different extractants, as isopentanol, 2-Ethyl-1-hexanol, n-Propyl acetate, and dichloromethane. The liquid–liquid equilibrium data of TFE + water +{isopentanol or 2-ethyl-1-hexanol or n-propyl acetate or dichloromethane} at standard pressure and 303.2 K were measured. The estimated partition coefficient ( D ) and separation factor ( S ) of TFE are higher than 1. Meanwhile, Othmer-Tobias and Hand's empirical equations verified the experimental data's consistency, and the squares of its linear correlation are all greater than 0.99. The NRTL and UNIQUAC activity coefficient models were used to correlate the experimental data, and different model parameters were obtained by regression. After comparing the calculated values of the model with the experimental data, it was found that the root means square deviation ( RMSD% ) was less than 0.34%, which indicate that both models have a reasonable correlation with the experimental data of the ternary system and can accurately predict the experimental data.

Measurement and Correlation of Solubility of Marbofloxacin in 12 Pure Solvents from 283.15 to 328.15 K

Zhiying Wu,Weiling Li,Ping Yu,Xiaoyu Fan,Hua Sun,Hua Zhao,Yue Zhang

The solubility of marbofloxacin in 12 pure solvents (methanol, ethanol, isopropanol, n-propanol, n-butanol, tert-amyl alcohol, acetonitrile, ethyl acetate, acetone, toluene, tetrahydrofuran, and 1,4-dioxane) at T = 283.15 to 328.15 K and P = 101.3 kPa was measured by a dynamic laser monitoring method. Results of these experiments demonstrate that the solubility of marbofloxacin in those 12 pure solvents increased with the increase of temperature. The experimental results showed that the solubility of marbofloxacin in the pure solvents decreased in the order of tetrahydrofuran > acetone > ethyl acetate > methanol ≈ acetonitrile (before 305.30 K) or > methanol ≈ acetonitrile > ethyl acetate (behind 305.30 K) > 1,4-dioxane > n-butanol > n-propanol > ethanol > tert-amyl alcohol > isopropanol > toluene. The Apelblat model, λh model, and nonrandom two-liquid (NRTL) model were used to correlate with the experimental solubility data. Compared with the λh model and NRTL model, the Apelblat model has a better correlation with the experimental values. The experimental solubility data and the correlation model in this study can be helpful for the related scientific research and scale-up production.

Preparation and characterization of nanoporous polyimide membrane by the template method as low-k dielectric material

Sude Ma,Yan Wang,Chun Liu,Qian Xu,Zhonghua Min

In order to decrease the resistance–capacitance delay and signal crosstalk in ultra large-scale integrated circuits (ULSIC), dielectric materials with ultra low dielectric constants are developed to be the replacement of silicon dioxide. Introduction of air on the matrix material is an important method to reduce the dielectric constant, and polyimide (PI) is the most promising polymer to prepare porous matrix material for its distinct advantages. PI membrane with nanopores was prepared by the method of template method (i.e. thermolysis of polystyrene nanospheres in the matrix) following the synthesis of template. The nanoporous membrane was characterized by Fourier transformer infrared, scanning electron microscopy, thermogravimetric analysis, and the dielectric constant of which was measured. Results showed that uniform nanopores about 100–200 nm were formed in the PI membrane, and dielectric constant of which was decreased to 2.08 from 3.34. The nanoporous membrane can be applied as potential low- k dielectric material in ULSIC. Copyright © 2015 John Wiley & Sons, Ltd.

Thermochemical properties for a series of microporous borophosphates of MI[ZnBP2O8] (MI = Na, K, Rb, Cs)

Pan Liang,Qiu-Yue Kang,Lu Du,Zhi-Hong Liu

Two pure microporous materials, Rb[ZnBP 2 O 8 ] and Cs[ZnBP 2 O 8 ], have been synthesized and characterized by XRD, FT-IR, DTA-TG techniques and chemical analysis. The molar enthalpies of solution of Rb[ZnBP 2 O 8 ] and Cs[ZnBP 2 O 8 ] (s) in 3   mol   ·   dm −3 HCl (aq), of Zn(PO 3 ) 2 (s) in (HCl   +   H 3 BO 3 ) (aq), and of RbCl (s)/CsCl (s) in [Zn(PO 3 ) 2   +   HCl   +   H 3 BO 3 ] (aq) were measured by microcalorimeter at T   =   298.15   K, respectively. With the incorporation of the previously determined enthalpy of solution of H 3 BO 3 (s) in 3   mol   ·   dm −3 HCl (aq), together with the use of the standard molar enthalpies of formation for Zn(PO 3 ) 2 (s), RbCl (s)/CsCl (s), H 3 BO 3 (s), HCl (aq) and H 2 O (l), the standard molar enthalpies of formation of −(3198.5   ±   1.2)   kJ   ·   mol −1 for Rb[ZnBP 2 O 8 ] and −(3212.7   ±   1.2)   kJ   ·   mol −1 for Cs[ZnBP 2 O 8 ] at T   =   298.15   K were obtained on the basis of the appropriate thermochemical cycle. In addition, the molar enthalpy of formation of −(2944.4   ±   1.2)   kJ   ·   mol −1 for [ZnBP 2 O 8 ] − has also been estimated by a group contribution method, which can be used to predict the Δ f H m θ ${\mathrm{\Delta }}_{\text{f}}{H}_{\text{m}}^{\mathrm{\theta }}$ of the other similar borophosphates. Moreover, these data have been further used to compare the thermodynamic stability of this series of borophosphates.

Facile surfactant-thermal syntheses and characterization of quaternary copper thioantimonates(III) ACu2SbS3 (A = K, Rb, Cs)

Yaying Shen,Chang Liu,Peipei Hou,Mingjia Zhi,Chunmei Zhou,Wenxiang Chai,Qichun Zhang,Yi Liu

Three new quaternary thioantimonates(III) ACu 2 SbS 3 (A = K, Rb, Cs) have been prepared through the surfactant-thermal method. X-ray single crystal diffraction analysis reveals that these three compounds are isostructural and feature a two-dimensional layered structure. Both experimental and theoretical studies confirm they are semiconductors with narrow band gaps. Our results clearly indicated that surfactants, as reaction media, could offer exciting opportunities for exploring novel multinary chalcogenides with diverse crystal structures and interesting physical properties.

Solubilities of crotonic acid in different organic solvents at several temperatures from (278.15 to 333.15) K

Zheng Cao,Yonghong Hu,Yumei Kai,Jiaojiao Li,Wenbiao Zhi,Wenge Yang

In our study the solubilities of crotonic acid in methanol, ethanol, 2-propanol, 1-butanol, acetic acid, N,N -dimethylformamide, ethyl acetate and acetonitrile were experimentally determined over the temperature range of (278.15–333.15)   K at around 5   K intervals by employing an analytical stirred-flask method. The experimental solubility data were well correlated with the modified Apelblat equation, in different kinds of solvents the values of the sum of MPD were 6.3. The thermodynamic functions were evaluated by two methods and the results were the same. The dissolving process was endothermic, entropy-driving and non-spontaneous. It was necessary to use the experiment data and correlation models in the reaction and purification of crotonic acid.

ZnPc-MWCNT/sulfonated poly (ether ether ketone) composites for high-k and electrical energy storage applications

Wenhan Xu,Yunhe Zhang,Gang Yang,Xiang Yu,Jie Liu,Zhenhua Jiang

Low-k and superior comprehensive property hybrid materials of a fluorinated polyimide and pure silica zeolite

Zhenxun Huang,Jianqing Zhao

In this study, various amounts of an amino-derivative of pure silica zeolite nanocrystals (A-PSZN) were blended with fluorinated poly(amic acid) (FPAA) to form a FPAA/A-PSZN precursor solution, and the fluorinated polyimide (FPI)/A-PSZN hybrid films were prepared via spin-coating and following thermal imidization of the FPAA/A-PSZN solution. A series of FPI/A-PSZN hybrid films were investigated scientifically based on the dielectric constant (k), water absorption, dynamic mechanical and thermal and mechanical properties. It is found that the k value decreases from 3.11 for pristine FPI to 2.65 for the FPI/7 wt% A-PSZN hybrid, which is attributed to the air within the micropore of A-PSZN and the inhibited molecular polarization originating from the internal cross-linking structure of hybrids. Due to the effective phase interconnection and the inherent excellent property of A-PSZN, on the other hand, the incorporation of A-PSZN results in the improvement of the storage modulus, glass transition temperature, thermal stability, Young's modulus, tensile strength and the decrease of water absorption, and thermal expansion coefficients for materials. The results indicate that the incorporation of A-PSZN is a promising approach to reduce the k value and improve the comprehensive properties of FPI, and the FPI/A-PSZN hybrid materials are potentially useful in the microelectronic industry.

ASb2(SO4)2(PO4) (A = H3O+, K, Rb): Layered Structure Containing Ordered Sulfate and Phosphate Anions

Xiao Zhao,Dajiang Mei,Jingli Xu,Yuandong Wu

Three compounds A Sb 2 (SO 4 ) 2 (PO 4 ) ( A = H 3 O + , K, Rb) were obtained from the reactions of Sb 2 O 3 , A 2 CO 3 ( A = Li, Rb) or K 2 SO 4 and NH 4 H 2 PO 4 in H 2 SO 4 (98 %) at 220–250 °C. Their structures were determined by single-crystal X-ray diffraction. All compounds crystallize in the triclinic space group P (no.2) and are isostructural. The crystal structures consist of two-dimensional 2 ∞ [Sb 2 (SO 4 ) 2 (PO 4 )] – anionic layers and alkali cations, which are located between anionic layers. The anionic layers are composed of [SbO 4 ] ψ-trigonal bipyramids, [SbO 5 ] ψ octahedra, [SO 4 ] tetrahedra, and [PO 4 ] tetrahedra. All compounds are characterized by solid state UV/Vis/NIR diffuse reflectance spectra, FT-IR spectroscopy, and Raman spectroscopy.

Phase equilibrium and activity coefficients in ternary systems at 298.15 K: RbCl/CsCl + ethylene carbonate + water

Xiuhua Hao,Shuni Li,Quanguo Zhai,Yucheng Jiang,Mancheng Hu

The (solid   +   liquid) equilibrium (SLE) and (liquid   +   liquid) equilibrium (LLE) of RbCl/CsCl   +   ethylene carbonate (EC)   +   H 2 O ternary systems were carefully investigated at 298.15   K. The SLE and LLE data were correlated by the corresponding equations respectively. Furthermore, the thermodynamic properties of RbCl/CsCl in the EC–water systems were determined by potentiometric method at T   =   298.15   K. The experiment data were correlated by the Pitzer, modified Pitzer and the extended Debye–Hückel equations. The mean activity coefficients, osmotic coefficients and excess Gibbs free energies, standard Gibbs free energy of transfer and the standard solubility product of systems were calculated. The mean activity coefficient γ ± decreases with the increase of the molality of electrolyte at the fixed mass fraction of EC. But γ ± vary abnormally with the increase of the EC content. The result of Δ G t 0 reflects the spontaneously transfer of the electrolytes from water to the mixed solvents.