函数P-集合与同物系物质结构-物性规律发现

利用函数P-集合理论研究了同物系结构-物性的构效关系。通过函数P-集合的动态特性筛选物质结构的最佳结构参数,利用函数P-集合的规律特性寻求最优预测规律函数,并将回归形式的规律函数引入P-集理论的研究中,预测了链烷烃的色谱保留指数,复相关系数达到了0.999。

及物性动词-小品词结构的语序问题

语音因素、句法因素、语义因素和语用因素影响英语及物性动词-小品词结构的语序,"末端重量"、信息结构及语义靠近等可以对其两种语序选择进行解释,但没有统一性。本文运用可别度领前原理和语义靠近原理对其进行统一、简明的解释,认为连续式和分裂式这两种语序并非自由选择,而是可别度领前原理和语义靠近原理共同作用的结果。

Synthesis,crystal structure and photo-physical properties of tris(4-methyl-2,5-diphenylpyridine)iridium for OLED

Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent materials.In this paper,Ir(bmppy)_(3),tris(4-methyl-2,5-diphenylpyridine)iridium,was synthesized and elvaluted for photo-physical characteristics.Single crystals suitale for X-ray diffraction(XRD)were grown from a mixture solvent of dichloromethane and absolute ethanol.The composition and structur of Ir(bmppy)_(3)were determined by element analysis,NMR spectra and XRD.The complex crystallizes in the monoclinic symmetry with the space group P21/c with a slightly distorted octahedral configuration.As measured by UV-Visible and photoluminescence spectra,Ir(bmppy)_(3) displays a maximum emission at at 527 nm at ambient temperature,a typical green-emitting profile.The complex has potential for application in the OLED industry.

Exploration for a Natural Selenium Supplement——Characterization and Bioactivities of Se-containing Polysaccharide from Garlic

A Se—containing polysaccharide(Se-GPS),with average molecular weight of 1.5×10~4 was isolated from Hubei Enshi garlic(Allium sativum L.)and purified by means of Sephadex G25 to G200 chromatographies.Its chemical homogeneity and composition were studied by optical rotation,HPLC and paper chromatographical methods.The abilities of scavenging active oxygen free radicals and inhibiting the damage of erythrocyte membrane by SiO_2 were established by spin trapping ESR studies.Se-GPS was shown to inhibit human cytomegalovirus by plague reduction assays and cytopathogenic effect tests.

Effect of heat treatment on microstructure and tensile strength of NiCoCrAl alloy sheet fabricated by EB-PVD

The NiCoCrAl alloy sheet was fabricated by electron beam physical vapor deposition technique and the effects of the heat treatment on the microstructure and tensile strength of the NiCoCrAl alloy sheet were investigated. The heat treatment at 1050 °C is favorable to improve the interface bonding between the columnar structures due to the disappearance of the intergranular gaps. Comparing with the thin NiCoCrAl alloy sheet before heat treatment, the Ni3Al phase appears in the NiCoCrAl alloy sheet after heat treatment, which is favorable to improve the interface bonding between the columnar structures. The increase in the tensile strength and elongation is attributed to the improvement of the interface bonding between the columnar structures. The residual stress in the NiCoCrAl alloy sheet after heat treatment is reduced significantly, which also confirms that the interface bonding is improved by the heat treatment.

Effects of Fe-Al intermetallic compounds on interfacial bonding of clad materials

The growth of intermetallic compounds at the interface between solid Al and Fe and the effects of intermetallic compound layers on the interfacial bonding of clad materials were investigated. The results showed that the interface between the solid Fe and Al formed by heat-treatment consisted of Fe2Al5 and FeAl3 intermetallic compound layers, which deteriorated the interfacial bonding strength. Fractures occurred in the intermetallic compound layer during the shear testing. The location of the fracture depended on the defects of microcracks or voids in the intermetallic compound layers. The microcracks in the intermetallic compound layer were caused by the mismatch of thermal expansion coefficients of materials during cooling, and the voids were consistent with the Kirkendall effect. The work will lay an important foundation for welding and joining of aluminum and steel, especially for fabrication of Al-Fe clad materials.

Preparation of micro-nanostructure on titanium implants and its bioactivity

Surface modification of medical implants was considered as an effective method to improve the cellular behaviors and the integration of tissue onto materials. The micro-nanostructured surface on the titanium alloy was prepared by laser treatment and multiple acid etching. The surface morphologies of different titanium alloy substrates were characterized by scanning electron microscopy (SEM). The effects of micro-nanostructured surfaces on the cellular responses were investigated in vitro by observing hydroxyapatite formation, cell morphology and cell adhesion. The results indicate that the micro-sized structure promoted the adhesion and proliferation of cultured osteoblasts. Furthermore, the micro-nanostructured surface was more conducive to cell adhension stretching compared with the micro-structured surface. All results suggest that the micro-nanostructured surface improved the biocompatibility and integration of tissue onto titanium alloy implants.

Influence of Preparation Conditions on Structural Stability of Ordered Mesoporous Carbons Synthesized by Evaporation-induced Triconstituent Co-assembly Method

Various ordered mesoporous carbons （OMCs） have been prepared by evaporation-induced trieonstituent co-assembly method. Their mesostructural stability under different carbon content, aging time and acidity were conveniently monitored by X-ray diffraction, transmission electron microscopy, and N2 sorption isotherms techniques. The results show mesostruetural stability of OMCs is enhanced as the carbon content increases from 36% to 46%, further increasing carbon content deteriorates the mesostructural stability. Increasing aging time from 0.5 h to 5.0 h make the mesostructural stability go through an optimum （2.0 h） and gradually reduce framework shrinkage of the OMCs. Highly OMCs can only be obtained in the acidity range of 0.2-1.2 mol/L HC1, when the acidity is near the isoelectrie point of silica, the resulting OMCs have the best mesostructure stability. Under the optimum condition, the carbon content of 46%, aging time of 2.0 h, and 0.2 mol/L HCl, the resulting OMCs have the best mesostrueture stability and the highest BET surface areas of 2281 m2/g.

Structural Investigation of Technetium-Diphosphonate Complex 99mTc-MDP

Density functional theory method has been employed to investigate the structures of the prototypical technetium-labeled diphosphonate complex 99mTc-MDP, where MDP represents methylenediphosphonic acid. A total of 14 trial structures were generated by allowing for the geometric, conformational, charge, and spin isomerism. Based on the optimized structures and calculated energies at the B3LYP/LANL2DZ level, two stable isomers were determined for the title complex. And they were further studied systematically in comparison with the experimental structure. The basis sets 6-31G＊（LANL2DZ for Tc）, 6-31G＊（cc-pVDZ-pp for Tc）, and DGDZVP have also been employed in combination with the B3LYP functional to study the basis set effect on the geometries of isomers. The optimized structures agree well with the available experimental data, and the bond lengths are more sensitive to the basis set than the bond angles. The charge distributions were studied by the Mulliken population analysis and natural bond orbital analysis. The results reflect a significant ligand-to-metal electron donation.

Synthesis, crystal structure and magnetic properties of novel copper compound Cu(phen)(m-CBA)_2

A novel compound Cu（phen）（m-CBA）2 was synthesized with m-chlorobenzoic acid（m-CBA）, 1,10-phenanthroline（phen） and Cu（OAc）2·H2O. It was characterized by IR, UV, elemental analyses and X-ray crystallography. It crystallizes in the monoclinic crystal system with C2/c space group, a=2.9699（4） nm, b=1.15452（2） nm, c=1.5335（2） nm, β=111.118（2）°, V=4.905 1（1） nm3, Z=8, F（000）=2 328, R1=0.072 8, wR2=0.223 4 [I2σ（I）]. Structure analysis shows that the copper center coordinates with two nitrogen atoms from one 1,10-phenanthroline molecule, two oxygen atoms from two m-chlorobenzoic acid molecules, giving a distorted squared planar coordination geometry. This novel compound shows paramagnetic interactions between copper centers.

Prediction of the thermo-elastic properties of knitted structural composites using FEM

It is a very important and complex task to estimate the thermo-elasticproperties of a textile structural composite. In this paper, the finite element method (FEM) wasused for the prediction of the orthotropic thermo-elastic properties of a composite reinforced byglass fiber knitted fabric. In order to define the final 3-D configuration of the loop reinforcingstructure, the interactions between the adjacent loops, the large displacement and the contactelements without friction were considered. The values predicted were compared with the experimentalresults.

Study on the Changes of Non-structural Carbohydrates and Nitrogen Contents of Quercus aquifolioides Scrub along Different Elevation Gradient

[Objective] The aim was to compare the content changes between the non-structural carbohydrates（NSC）and the total nitrogen in various growing seasons,and to explore the response relationship between altitude and the contents.[Method] Taking Quercus aquifolioides scrub which widely distributed in Zheduoshan in the west of Sichuan as the experimental objects,the changes between NSC and the toal nitrogen in various growing seasons at different altitude were studied.[Result] The results showed that the content of NSC in Quercus aquifolioides underground increased with the lift of elevation in the dormancy,but decreased in the early germination,growing period and growth stage.The content of NSC in the ground tissue changed non-linearly with increasing elevation.In addition,the total nitrogen of Quercus aquifolioides organizations was decreasing with increasing elevation in the dormant period,which did not change significantly in the other periods.This result implied that the content of NSC in Quercus aquifolioides underground was more sensitive to temperature.[Conclusion] The experiment laid basis for the exploration of the physical and ecological mechanism of underground plants adaptability to highland environment,their response to global climate changes and adjustment to high altitude ecological system.

Effect of high-voltage discharge non-thermal plasma on g-C_3N_4 in a plasma-photocatalyst system

The synergistic effect of high voltage discharge non‐thermal plasma(NTP)and photocatalysts on contaminant removal has repeatedly confirmed by plenty of researches.Most previous plasma‐photocatalyst synergistic systems focused on the utilization of the ultraviolet light but ignored the visible light generated by high voltage discharge.Graphitic carbon nitride(g‐C3N4),a metal‐free semiconductor that exhibits high chemical stability,can utilize both the ultraviolet and visible light from high voltage discharge.However,the synergistic system of NTP and g‐C3N4 has been researched little.In this paper,the effect of NTP generated by dielectric barrier discharge(DBD)on g‐C3N4 is studied by comparing the photocatalytic activities,the surface physical structure and the surface chemical characteristics of pristine and plasma treated g‐C3N4.Experimental results indicate that the DBD plasma can change the physical structure and the chemical characteristics and to further affect the photocatalytic activity of g‐C3N4.The effect of NTP on g‐C3N4 is associated with the discharge intensity and the discharge time.For a long time scale,the effect of NTP on g‐C3N4 photocatalysts presents a periodic change trend.

Tuning the product selectivity of SAPO-18 catalysts in MTO reaction via cavity modification

The AEI cavity of SAPO-18 catalyst was modified with zinc cations with the conventional ion exchange procedure.The cavity modification effectively tunes the product selectivity,and shifts the products from mainly propylene to comparable production of ethylene and propylene in methanol to olefin(MTO)reaction.The incorporation of zinc ions and the generation of bicyclic aromatic species in the AEI cavity of SAPO-18 catalysts introduce additional diffusion hindrance that exert greater influence on the relatively bulky products(e.g.propylene and higher olefins),which increase the selectivity to small-sized products(e.g.ethylene).It appears that the incorporated zinc cations facilitate the generation of lower methylbenzenes which promote the generation of ethylene.The cavity modification via incorporating zinc ions effectively tunes the product selectivity over SAPO molecular sieves with relatively larger cavity,which provides a novel strategy to develop the potential alternative to SAPO-34 catalysts for industrial MTO reaction.

Design and Synthesis of Novel Fluorine-containing Acrylates

A series of novel fluorine-containing acrylates 6a-6g were synthesized via the condensation of ethyl cyanoacetate and trifluoroacetic anhydride, followed by chloridization and the coupling reaction with amines. These new compounds exhibited some biological activity as preliminary bioassay indicated. A plausible reaction mechanism was outlined and discussed.

Syntheses and Crystal Structures of Bis-[oxo-bis(p-ferrocenylbenzoxy di-n-propyltin)](I) and Bis[oxo-bis(β-ferrocenoylpropionyloxy di-n-propyltin )](II)

Bis-[oxo-bis(p-ferrocenylbenzoxy di-n-propyltin)] I and bis-[oxo-bis(-ferrocenoyl- propionyloxy di-n-propyltin)] II were synthesized and their crystal structures have been determined by X-ray diffraction analysis. The compound I2C6H6 ([(FcC6H4COOSnPr2)2O]22C6H6 or C92H108Fe4O10Sn42C6H6, Mr = 2384.16) is of triclinic, space group P?with a = 12.826(4), b = 13.099(5), c = 17.539(5) ? = 78.229(5), ?= 71.852(5), = 62.746(5)? V = 2483(1) ?, Z = 1, Dc = 1.490 g/cm3, = 0.71073 ? (MoK? =1.611 mm-1 and F(000) = 1128. The structure was refined to R = 0.0491 and wR = 0.1053 for 4690 unique reflections with I > 2(I). The compound IIC6H6 ([(FcCOCH2CH2COOSnPr2)2O]2C6H6 or C80H108Fe4O14Sn4C6H6, Mr = 2115.93) is of triclinic, space group P?with a = 11.260(4), b = 14.126(5), c = 15.961(6) ? = 91.400(6), = 110.654(6), = 104.931(6), V = 2277(1) 3, Z = 1, Dc = 1.510 g/cm3, = 0.71073 ? (MoK? = 1.750 mm-1 and F(000) = 1046. The structure was refined to R = 0.0466 and wR = 0.1138 for 5061 unique reflections with I > 2(I). The two compounds have the similar structures: both are dimers containing centrosymmetric Sn2O2 cores. But there are some differences in the ligating modes between the carboxylate groups and the Sn atoms.

Crystal Structure and Magnetic Property of 2-（Imidazo[1,2-α]pyri-din-2-yl）- 2-oxoacetic Acid and Its Perchlorate

We herein report two crystals based on 2-（imidazo[1,2-a]pyridin-2-yl）-2-oxoacetic acid rad- ical and its perchlorate, and investigate the relationship between magnetic properties and crystal stacking structures or supramolecular interactions. 2-（imidazo[1,2-a]pyridin-2-yl）- 2-oxoaeetic acid radical in two crystals mainly exist as diamagnetic dimer formed via short atomic contacts or supramolecular interactions （hydrogen bonds, anion-Tr or lone- pair-~r interactions）, leading to low magnetic susceptibilities. 2-（imidazo[1,2-a]pyridin-2-yl）- 2-oxoaeetic acid radical crystal exhibits quasi-one-dimensional columnar stacking chain and weak antiferromagnetism. However, its perchlorate crystal possesses one-dimensional double- stranded chain structure assembled through double hydrogen bonds and anion-To interactions, and reveals weak ferromagnetism.

Synthesis and Crystal Structure of 3,3′-(Hexane-1,6-diyl)bis(1-acetyl-5,5-dimethylhydantoin),a New Inducer of Differentiation

The title compound (C20H30N4O6, Mr = 422.48) was synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in the triclinic system, space group P with cell parameters: a = 8.330(2), b = 8.468(2), c = 16.017(3) ? ?= 97.30(3), ?= 92.33(3), ?= 103.94(3)? V = 1084.7(4) ?, Dc = 1.294 g/cm3, Z = 2, F(000) = 452 and ?= 0.096 mm-1. The structure was refined to R = 0.0483 for 3732 observed reflections with I > 2s(I) and wR = 0.1335 for 4828 unique reflections. The hydantoin rings are planar and the two ring planes of one molecule are paralleled to each other.

Synthesis, Crystal Structure and Nonlinear Optical Properties of Nickel(Ⅱ) Complex with Schiff-base Ligand

The nickel(Ⅱ) complex with the new ligand of S-benzyl-b-N-[10-ethyl- phenothiazine-3-methylene]dithiocarbazate(HL) crystallizes in the triclinic system, space group P?with a = 7.516(1), b = 11.322(1), c = 13.366(1) , a = 84.818(1), b = 81.688(1), g = 76.037(1), V = 1090.26(3) 3, Z = 1, Dc = 1.413 g/cm3, F(000) = 482, m(MoKa) = 0.774 mm-1 (l = 0.7103 ?, R = 0.0573 and wR = 0.1375 for 3357 observed reflections with I ≥ 2s(I). The HL has lost a proton from its tautomeric thiol form and acts as a single negatively charged bidentate ligand coordinating to the nickel ion via the mercapto sulfur and b-nitrogen atoms. The geometry around Ni(Ⅱ) is almost square-planar with two equivalent NiN and NiS bonds. The nonlinear absorption of HL and NiL2 solutions (in DMF) was measured by open-aperture Z-scan technique at the wavelength of 532 nm.

Syntheses, Structures and Magnetic Properties of Two Co(II) Coordination Polymers with 2,5-Pyridine Dicarboxylic Acid

The hydro(solvo)thermal reactions of cobalt powder or its chloride with 2,5- pyridine dicarboxylic acid (H2PYDC) yielded two new complexes: [Co(II)2(PYDC)2(H2O)2- (H2O)4]n 1 and {Co(II)[NH2(CH3)2]2(PYDC)2}n 2. It is observed that the reactive solvents result in different connectivity modes of ligand and diverse dimensional extension of crystal structures. The correlation between structure and magnetic property will be discussed in this paper. Crystal data for 1: space group P1, a = 7.0419(17), b = 8.937(2), c = 9.6182(19) ?, α = 91.532(4), β = 99.869(10), γ = 107.889(11)o, V = 565.5(2) ?3, Z = 1, Dc = 1.845 g/cm3, μ = 1.56 mm-1, F(000) = 322 , R = 0.0505 and wR = 0.1580; and those for 2: space group C2/c, a = 14.9075(6), b = 8.2523(3), c = 16.9643(2) ?, β = 100.982(2)o, V = 2048.75(11) ?3, Z = 4, Dc = 1.560 g/cm3, μ = 0.892 mm-1, F(000) = 996, R = 0.0443 and wR = 0.1134.