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湖南大学学报（自然科学版） 2009年第S1期36卷 55-59页

作者： LU Zhen1,2,ZHANG Ji-li1,MA Liang-dong1,HE Juan3(1.school of Civil & Hydraulic engineering,Dalian University of Technology,Dalian,Liaoning 116023,china 2.Municipal and environmental engineering Research Center,Shenyang Jianzhu University,Shenyang,Liaoning 110168,china 3.school of Municipal & environmental engineering,Harbin Institute of Technology,Harbin,Heilongjiang 150090,china) school of Civil and Hydraulic engineering Dalian University of Technology Dalian 116023 China Municipal and environmental engineering Research Center Shenyang Jianzhu University Shenyang 110168 China school of Municipal and environmental engineering Harbin Institute of Technology Harbin 150090 China

Because of its broad spectrum and high efficiency,the microwave disinfection was used to control the airborne microbial contaminates in VAC *** microwave disinfection devices were developed combined with air filter,the design and calculation method was presented,and the disinfection effects on White staphylococcus,Staphylococcus aureus,Bacillus Subtilis,Escherichi coli were *** results show that the major influence factors on disinfection effect are microwave power,water-content of filter material,disinfecting *** 15 min,the kill ratio is >90%,and the log value is >*** microwave field is uniform and the kill effect of bacteria on each surface of filter is the same,without statistically significant difference.

关键词： VAC system microwave disinfection airborne microbe microwave power kill ratio

Effect of activation agents on the surface chemical properties and desulphurization performance of activated carbon

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Science china(Technological Sciences) 2010年第9期53卷 2515-2520页

作者： ZHANG XiangLan,ZHANG Yan,WANG ShuangSheng,ZHANG JingJing & ZHOU Wei school of chemical and environmental engineering,china University of Mining and Technology (Beijing),Beijing 100083,china school of chemical and environmental engineering China University of Mining and Technology (Beijing) Beijing China

Flue gas pollution is a serious environmental problem that needs to be solved for the sustainable development of *** surface chemical properties of carbon have great influence on its desulphurization performance.A series of activated carbons (ACs) were prepared using HNO3,H2O2,NH3·H2O and steam as activation agents with the aim to introduce functional groups to carbon surface in the ACs preparation *** ACs were physically and chemically characterized by iodine and SO2 adsorption,ultimate analysis,Boehm titration,and temperature-programmed reduction (TPR).Results showed that the iodine number and desulphurization capacity of NH3·H2O activated carbon (AC-NH3) increase with both activation time,and its desulphurization capacity also increases with the concentration of activation ***,HNO3 activated carbon (AC-HNO3) and H2O2 activated carbon (AC-H2O2) exhibit more complex *** their iodine numbers increase monotonously with activation *** with steam activated AC (AC-H2O),the nitrogen content increases 0.232% in AC-NH3 and 0.077% in *** amount of total basic site on AC-HNO3 is 0.19 mmol·g-1 higher than that on AC-H2O.H2O2 activation introduces an additional 0.08 mmol·g-1 carboxyl groups to AC surface than that introduced by steam *** desulphurization capacity of ACs in simulate flue gas desulphurization decreases as follows: AC-NH3 > AC-HNO3 > AC-H2O2 > *** sequence is in accord with the SO2 catalytic oxidation/oxidation ratio in the absence of oxygen and the oxidation property reflected by *** the presence of oxygen,all adsorbed SO2 on ACs can be oxidized into *** desulphurization capacity increases differently according to the activation agents;the desulphurization capacity of AC-NH3 and AC-HNO3 improves by 4.8 times,yet AC-H2O increases only by 2.62 as compared with the desulphurization of corresponding ACs in absence of oxygen.

关键词： activated carbon activation agent surface chemical property desulphurization TPR

Size effect of fullerene cages and encaged clusters in M3N@C2n

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Science china Chemistry 2009年第5期52卷 584-589页

作者： GAN LiHua school of Chemistry and chemical engineering, Southwest University, Chongqing 400715, china school of Chemistry and chemical engineering Southwest University Chongqing China

Based on the calculated findings that the sizes of encaged clusters determine the structures and the stability of C80-based trimetallic nitride fullerenes (TNFs), more extensive density functional theory calculations were performed on M3N@C68, M3N@C78 and M3N@C80 (M=Sc, Y and La). The calculated results demonstrated that the structures and stability undergo a transition with the increasing of the sizes of the cages and clusters. Sc3N is planar inside the three considered cages, Y3N is slightly pyramidal inside C68-6140 and C78-5 and planar inside I h C80-7, however, La3N is pyramidal inside all the three cages. Those cages with pyramidal clusters inside deformed considerably, compared with their parent cages. In these cases, the bonding of metallic atoms toward the cages does not play an impor-tant role, and the encaged cluster tends to be located inside the cages with the largest M-M and M-C distances so that the strain energy can be released mostly. These calculations revealed the size effect of fullerene cages and encaged clusters, and can explain the position priority of M3N inside fullerene cages and the differences in yield of M3N@C2n.

关键词： trimetallic nitride fullerenes (TNFs) density functional theory (DFT) size effect stability

Theoretical study of bifurcated bent blue-shifted hydrogen bonds CH_2…Y

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Science china Chemistry 2008年第7期51卷 623-631页

作者： LI AnYong school of Chemistry and chemical engineering, Southwest University, Chongqing 400715, china school of Chemistry and chemical engineering Southwest University Chongqing China

Ab initio quantum chemistry methods were applied to study the bifurcated bent hydrogen bonds Y… H2CZ (Z = O, S, Se) and Y…H2CZ2 (Z = F, Cl, Br) (Y = Cl-, Br-) at the MP2/6-311++G(d,p) and MP2/6-311++G(2df,2p) levels. The results show that in each complex there are two equivalent blue-shifted H-bonds Y…H—C, and that the interaction energies and blue shifts are large, the energy of each Y…H—C H-bond is 15-27 kJ/mol, and Δr(CH) = -0.1 - -0.5 pm and Δv(CH) = 30 - 80 cm-1. The natural bond orbital analysis shows that these blue-shifted H-bonds are caused by three factors: large rehybridization; small direct intermolecular hyperconjugation and larger indirect intermolecular hy- perconjugation; large decrease of intramolecular hyperconjugation. The topological analysis of elec- tron density shows that in each complex there are three intermolecular critical points: there is one bond critical point between the acceptor atom Y and each hydrogen, and there is a ring critical point inside the tetragon YHCH, so these interactions are exactly H-bonding.

关键词： bifurcated bent H-bonds blue-shifted H-bonds topological property of electron density intramolecular hyperconjugation

Photocatalytic degradation of methyl orange over ITO/CdS/ZnO interface composite films

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Journal of environmental Sciences 2009年第7期21卷 991-996页

作者： WEI Shouqiang, SHAO Zhongcai, LU Xudong, LIU Ying, CAO Linlin, HE Yan school of environmental and chemical engineering, Shenyang Ligong University, Shenyang 110168, china. school of environmental and chemical engineering Shenyang Ligong University Shenyang 110168 China

ITO/CdS/ZnO interface composite films were successfully prepared by subsequent electrodeposition of CdS and ZnO onto indium tin oxide （ITO） glass substrates. The obtained ITO/CdS/ZnO composite films were characterized with X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and UV-Vis spectroscopy. The photocatalytic activity of ITO/CdS/ZnO composite films were investigated using methyl orange （MO） as a model organic compound under UV light irradiation. The influence of operating parameters on MO degradation including initial concentration of MO, pH value of solution, and inorganic anion species over the composite films were examined. A blue shift of absorption threshold was observed for the ITO/CdS/ZnO film in comparison with ITO/ZnO film. ITO/CdS/ZnO composite films prepared under specific conditions showed a higher photocatalytic activity than that of ITO/ZnO films. It was also found that the photocatalytic degradation of MO on the composite films followed pseudo-first order kinetics.

关键词： electrodeposition zinc oxide cadmium sulfide composite film photocatalytic activity

Expansive Behaviors of Self-stressing Concrete under Different Restraining Conditions

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Journal of Wuhan University of Technology(Materials Science) 2011年第4期26卷 780-785页

作者：常旭 College of Civil engineering Henan Polytechnic University

The expansive behaviors of the expensive concrete under different restraining conditions were systemically studied. The experimental results indicate that expansive deformation obviously increases before 10 days and tends to be constant after 25 days regardless of the restraining conditions. The mixture ratio of expansive cement and restraining conditions are the main factors affecting expansive deformation. Self-stress can be obtained when the expansive deformation is restrained. The higher self-stress could be obtained when the expensive concrete is restrained by steel tube. For specimens under steel tube restraining, the wall thickness and the length of the steel tube have important influence on self-stress. Both the radial self-stress and axial self-stress in concrete core increase when wall thickness or length of the steel tube increases.

关键词： self-stress expansive concrete restraining condition

Preparation, characterization and salt-resistance of a coal based super absorbent composite

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Mining Science and Technology 2010年第6期20卷 864-871页

作者： CHU Mo, HUANG Zhanbin, XU Bang, FANG Tao, DUAN Hui school of chemical and environmental engineering, china University of Mining & Technology, Beijing 100083, china school of chemical and environmental engineering China University of Mining & Technology Beijing 100083 China

Potassium humate was extracted from brown coal. A novel super absorbent composite, poly （acrylic acid-co-acryla- mide）/potassium humate （PAA-AM/KHA）, was prepared by graft polymerization of acrylic acid, acrylamide and coal based potassium humate using N, N＇-methylenebisacrylamide as a crosslinker and potassium peroxydisulfate as an initiator. The effects of reaction temperature, degree of neutralization of the poly （acrylic acid） and the amounts of crosslinker, initiator and potassium humate were investigated. Salt resistance tests were also carded out. The composite prepared under optimal conditions had a potassium bumate content of 10% and exhibited a water absorption of 770 g/g in distilled water, and 349, 286 and 41 gig in 0.5 mol/L KC1, MgC12 and A1CI3 solutions respectively. The results indicate that the salt resistance of PAA-AM/KHA was superior to that of poly （acrylic acid-co-acrylamide） because of the collaborative effect of functional groups of the coal based potassium humate. The PAA-AM/KHA micro powder was characterized by IR spectroscopy and the micrographic surface was characterized by scanning electron microscopy. Introduction of potassium humate into the poly （acrylic acid-co-acrylamide） structure creates a composite more suitable for use as a water-managing material in the renewal of arid and desert environments. The salt resisting property of the composite is improved, production costs are reduced and the growth stimulant effect is still present.

关键词： brown coal coal based potassium humate superabsorbent salt-resistant property

Boron rings containing planar octa- and enneacoordinate cobalt, iron and nickel metal elements

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Science china Chemistry 2008年第7期51卷 607-613页

作者： LUO Qiong school of Chemistry and chemical engineering, Central South University, Changsha 410083, china school of Chemistry and chemical engineering Central South University Changsha China

For a series of boron rings with planar hyper-coordinate 8th group transition metal atoms, singlet 1FeB8-2, multiplet kFeB9n (n = -1, k = 1; n = 0, k = 2), singlet 1CoB8n(n = -1, +1, +3), multiplet kCoB9n (n = +1, k = 2; n = 0, k = 1) and singlet 1NiB9+, the geometry structures have been optimized to be local minima on corresponding potential hyper-surfaces. The electron structures are discussed by orbital analysis and the aromaticity is predicted by nucleus-independent chemical shifts calculation at both the B3LYP/6-311+G* and BP86/6-311+G* levels of theory, respectively. The results suggest that all these structures with high symmetry planar geometries are stable and have aromatic properties with six π valence electrons.

关键词： planar hyper-coordinate transition metal DFT

Sorption of a triazol derivative by soils: importance of surface acidity

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Journal of environmental Sciences 2003年第3期15卷 383-387页

作者： WU De-yi (school of environmental Science and engineering, Shanghai Jiaotong University, Shanghai 200240, china.) school of environmental Science and engineering Shanghai Jiaotong University 上海 200240

The sorption of a triazol derivative, 1-(4-chlorophenyl)- 4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)penten-3-ol with a common name of S3307D, on fifteen soils and three H_2O_2-treated soils was investigated. The sorption isotherm for each untreated and treated soil was non-linear, and was best fitted to Freundlich sorption equation. Soils containing high amount of clay content or organic matter or both sorbed much higher amounts of the chemical than soils that had low contents of these soil constituents. H_2O_2-treated soils showed considerable sorptive affinity for S3307D. It was concluded that both organic matter and mineral fraction in natural soils contributed to the sorption of the basic compound. Sorption by the H_2O_2 treated soils increased as suspension pH decreased, but all suspension pHs exceeded the pKa of the compound by more than two units. This implies that organic base protonation can occur on surfaces of soil components, and surface acidity (exchangeable acidity ) is important in sorption process of the organic base rather than suspension pH.

关键词： sorption organic base soil surface acidity