Fabrication and characterization of Grass pea (Lathyrus sativus) protein isolate-Alyssum homolocarpum seed gum complex coacervate

The present work was carried out to fabricate Grass pea (Lathyrus sativus) protein isolate (GPPI) and Alyssum homolocarpum seed gum (AHSG) complex coacervate and investigate its morphological and structural properties. Formation of complex coacervates were studied by zeta potentiometry and turbidimetric analysis as function of different pHs (7.0–2.0) and GPPI to AHSG ratios (3:1 to 1:3). The critical pH values associated with the formation of soluble (pH_c) and insoluble (pH_φ1) complexes, and complete dissociation (pH_φ2) at GPPI to AHSG ratio (1:1) were found to be 4.8, 4.0, and 2.5, respectively. Formation of insoluble complex coacervate was maximum at pH 3.2 and GPPI to AHSG ratio of 1:1, where the highest yield (69%) was observed. Scanning electron microscopic (SEM) demonstrated that GPPI-AHSG complex had a rough branched-like structure. Results also showed that the complexation between GPPI and AHSG were formed through the electrostatic interaction and hydrogen bonding. Circular dichroism spectroscopy (CD) indicated that the β-sheet and random coil content in GPPI increased when AHSG molecules were added to protein solution. The fading of pure peaks of GPPI and AHSG in X-Ray diffraction (XRD) patterns of GPPI-AHSG complexes confirmed the alterations in the physical state of mixture from crystalline to amorphous. GPPI-AHSG complex coacervates had lower weight loss compared to individual GPPI and AHSG.     

混配配合物[Co(cpida)(C7H5N2)2]·C7H5N2·5H2O

在溶液中用N-(邻苯甲酸基)-亚氨基二乙酸、苯并咪唑和Co(Ac)2·4H2O进行自组装合成了标题三元金属混配配合物.用元素分析、红外光谱、单晶衍射对配合物的组成和结构进行了表征,确定配体N-(邻苯甲酸基)-亚氨基二乙酸中的3个羧基为单齿形式与中心金属钴离子配位.     

荧光法研究牛血清白蛋白与三羟基苯基荧光酮-钼(Ⅵ) 配合物探针的作用机理

用荧光光谱法研究了三羟基苯基荧光酮(TH-PF)-钼(Ⅵ)配合物与牛血清白蛋白的结合反应。探讨了TH-PF-Mo(Ⅵ)配合物对蛋白质内源荧光的猝灭机理,并测定了不同温度下的结合常数,温度为25 ℃时,荧光猝灭法测得该反应的结合常数为K=4.78×104 L·mol-1,温度为40 ℃时,荧光猝灭法测得该反应的结合常数为K=3.72×104 L·mol-1。根据Frster非辐射能量转移理论,确定了给体-受体之间的作用距离和能量转移效率(E=0.314),并根据热力学参数确定了TH-PF-Mo(Ⅵ)配合物与牛血清白蛋白之间的作用力类型,以静电引力为主。     

空间雷电探测实时采集定位系统

星载雷电探测定位系统是利用光学探测器探测闪电事件的地理位置和光脉冲波形,系统采用CPLD+DSP的数字图像处理方案,利用了CPLD复杂逻辑可编程特性将系统的部分或全部功能集成在一片CPLD上,减小了系统硬件复杂程度,节省了印制版空间.利用DSP高速数字信号处理特性完成实时处理图像数据的功能.系统用CPLD完成图像信号的采集、编码和存储控制,缩小了星载设备体积,简化了电路结构;用DSP完成大量图像数据处理工作,提高了系统工作的实时性.     

Determination of the second step microstructure for superhydrophobic surfaces

A selection of suitable microstructures is critical to fabrication and properties of superhydrophobic surfaces (SHS). In this study, we introduce a three‐dimensional droplet model to thermodynamically analyze the superhydrophobic properties for the purpose of determining the second step of a two‐step microstructure suitable for the SHS based on the common models within the reach of the existing macro‐machining technology. It is found that a sinusoidal microstructure is the most suitable, followed by a cone frustum and a prism in the composite wetting state, as well as the transition from hydrophilic to hydrophobic depends basically on the solid fraction rather than non‐determinative surface microscopic topography. The predictions of the model are found in quite good agreement with the experimental observations. This study will facilitate fabrication of the SHS on how to select the suitable morphology. Copyright © 2012 John Wiley & Sons, Ltd.     

Synthesis and Structure of a Manganese(Ⅱ) Complex: [Mn2·(dinitrobenzoic acid)4·(1,10-phen)2]n

The title compound, [Mn2·(dinitrobenzoic acid)4·(1,10-phen)2]n, has a linear chain structure containing binuclear [Mn2·(dinitrobenzoic acid)4(1,10-phen)2] repeat units. It crystallizes in the triclinic system, space group P1- with a = 7.9261(8), b = 12.1329(15), c = 14.847(2)(A), α = 103.845(5), β =101.424(5), γ= 92.618(4)°, Mr= 657.37, V= 1352.3(2) (A)3, Z = 2, Dc= 1.614 g/cm3, F(000) = 666, μ =0.567 mm-1, the final R = 0.0407 and wR = 0.1015 for 4081 observed reflections with I ＞ 2σ(Ⅰ). The Mn atom is six-coordinated by two N and four O atoms, forming a slightly distorted octahedral geometry. All Mn-O and Mn-N bond distances range from 2.093(2) to 2.310(2)(A). Two adjacent octahedral units are bridged together by two pairs of bi-monodentate carboxyl groups of different dinitrobenzoic acids to form an eight-membered ring with chair-typed configuration, thus generating a one-dimensional chain along the a axis.     

Synthesis and Structural Characterization of a New Cadmium(Ⅱ) Complex Bridged by Endo-norbornene-cis-5,6-dicarboxylic Acid

A polynuclear complex [Cd(endc)(H2O)]n·nH2O (endc = endo-norbomene-cis5,6-dicarboxylate anion) has been synthesized by the hydrothermal reaction of cadmium nitrate tetrahydrate with endo-norbomene-cis-5,6-dicarboxylic acid in 1:1 molar ratio,and structurally characterized by single-crystal X-ray diffraction.It crystallizes in monoclinic,space group P21/c with a = 1.16471(7),b = 0.95334(7),c = 0.91109(9) nm,Z = 4,V= 1.01035(14)nm3,Dc.= 2.160 g/cm3,μ= 2.172 mm-1,F(000) = 648,R =0.0302 and wR = 0.0752.According to structural analysis,each Cd(Ⅱ) ion is coordinated to six O atoms from three endc anions and one water molecule,giving a distorted octahedral geometry.Two- dimensional layer arrangement of the title complex is constructed from the bridging nature of endc.It is worth notice that adjacent two-dimensional layers are joined together to form a three-dimensional supramolecular framework via intermolecular hydrogen bonding interactions.     

Synthesis and Crystal Structure of a Novel Bimetallic Porphyrin Complex Salt {[MnTPP(CH3OH)2]3Fe(CN)6}·13H2O

A novel bimetallic porphyrin complex salt, {[MnTPP(CH3OH)2]3Fe(CN)6}·13H2O (TPP = tetraphenylporphyrin), has been synthesized and structurally characterized by X-ray diffraction analysis. The crystal is of trigonal, space group R-3 with a = b = 31.0618(10), c = 11.8366(8) (A), Z = 3, V = 9890.3(8) (A)3, C144H134FeMn3N18O19, Mr = 2641.36, Dc = 1.330 g/cm3, μ(MoΚα) = 0.463 mm-1, F(000) = 4131, R = 0.0525 and wR = 0.1382 for 3045 observed reflections (I ＞ 2((I)). The title complex is composed of one [Fe(CN)6]3- anion, three [MnTPP(CH3OH)2] cations and thirteen water molecules, which are connected by multiform hydrogen bonds leading to a 3D supramolecular network structure.     

Characterization and Crystal Structure of a New Holmium(Ⅲ) Complex with the Macrocyclic Ligand Derived from 2,6-Dfformyl-4-methylphenol and Diethylenetriamine

The title compound (13,27-dimethyl-3,6,9,17,20,23-hexaazatricyclo-[23.3.1.111,15]-triaconta- 1 (29),2,9,11,13,15(30), 16,23,25,27-decaene-29,30-diol-N3,N6,N9,O29,O30)-bis(nitrato-O,O')-holmium(Ⅲ) nitrate hydrate has been prepared and characterized by elemental analysis, infrared spectra, and electrospray mass spectra. Its crystal and molecular structures were determined by X-ray diffraction methods. The crystal crystallizes in the monoclinic system, space group C2/c with a = 23.737(12), b = 14.237(7), c = 19.801(10) (A), β = 91.36(1)°, Mr = 831.57, V = 6690(6) (A)3, Z = 8,Dc = 1.651 g/cma, F(000) = 3344, R = 0.0482 and wR = 0.0923. The holmium ion is located in one of the compartments of the macrocyclic ligand and presents a distorted tricapped trigonal prismatic coordination geometry. The macrocycle is coordinated with two oxygen and three nitrogen atoms.Two nitrates are chelated in the opposite positions of the macrocycle, and the third one is ionic.     

Regioselectivity Study on Propylene Polymerization Catalyzed by Neutral Salicyladiminato Pd（Ⅱ） Model Complex with DFT Method

Many attempts have been made to control the regioselectivity for olefin polymerization by varying the structures of ligands in catalysts. The regioselectivity of propylene polymerization was investigated by replacing a nitrogen atom in the Pd(Ⅱ) diimine catalyst with an oxygen atom from density functional theory method at the B3LYP/LANL2DZ level. The results show that the 1,2-insertion becomes a rival mechanism to the 2,1-insertion when the nitrogen atom is replaced by the oxygen atom leading to an asymmetric environment in the catalyst, and that the steric effect in the asymmetrical catalyst plays an important part in the polymerization. The insertion barrier from 2-O is much higher than that from 2-N. A pyramid transition state was characterized for the catalyst to convert 2-O back to 2-N through internal rotation. The propylene prefers to coordinate at the opposite side of O in the catalyst. This is the driving force for the internal rotation.The results are significant for isotactic and syndiotactic polymerization.