The electron structure and photocatalytic activity of Ti(IV) doped Bi_2O_3

Density functional theory (DFT) plays a significant role in the development of visible light responsive photocatalysts.Based on the first-principles plane-wave ultrasoft pseudopotential (USPP) method,the crystal structures of α,β,γ,and δ-Bi2O3 were optimally calculated for the total density of states (TDOS) and the partial density of states (PDOS) of Bi,O atoms.The calculation for Ti(IV) doped Bi2O3 supercell was carried out.The effects of Ti(IV)-doping on the electron structures and light absorption proper...     

Statistical and thermodynamic properties of binary self-condensing vinyl polymerization

The thermodynamic properties of a binary self-condensing vinyl polymerization system consisting of monomers and inimers are investigated by the principle of statistical mechanics.In detail,in terms of two types of canonical partition functions constructed from different viewpoints,the equilibrium free energy,the law of mass action and the size distribution of hyperbranched polymers are obtained.As an application,the specific heat,equation of state and isothermal compressibility concerning the polymerization...     

Preparation of Bio-beads and Their Atrazine Degradation Characteristics

Screened atrazine-mineralizing bacterium―Pseudomonas W4 was embedded inside an improved PVA- H3BO3 embedment matrix to make bio-beads to degrade atrazine. The atrazine degradation characteristics were studied. The preparation procedure of bio-beads was as follows: (1) preparing a mixture of 100, 12.5, 10, 1.5 and 1 g/L PVA, bentonite(Ca), activated carbon powder, sodium alginate and centrifuged Pseudomonas W4 bacterium, respectively; (2) the mixture was dropped into a gently stirred cross linker solution(pH...     

纳米TiO-2对模型病毒-f2噬菌体的吸附特性

为了提高饮用水处理系统对病毒的去除效果,本研究采用静态实验,研究纳米TiO2对模型病毒—f2噬菌体的吸附去除特性,系统考察TiO2投加浓度、病毒浓度、温度及pH值等因素对吸附效果的影响.实验结果表明：f2噬菌体在纳米TiO2表面的吸附符合准二级吸附动力学模型,遵循化学吸附机理,颗粒内扩散为该吸附过程中的速率控制步骤,但不是唯一控制步骤;纳米TiO2对f2噬菌体的吸附符合Freundlich等温吸附模型（qe=27.4Ce1.24）,属于多层吸附类型;在20~40℃范围内,温度对纳米TiO2的吸附性能影响不大,而酸性条件下更有利于纳米TiO2对f2噬菌体的吸附.     

Hyperspectral remote sensing image classification based on decision level fusion

To apply decision level fusion to hyperspectral remote sensing (HRS) image classification,three decision level fusion strategies are experimented on and compared,namely,linear consensus algorithm,improved evidence theory,and the proposed support vector machine (SVM) combiner.To evaluate the effects of the input features on classification performance,four schemes are used to organize input features for member classifiers.In the experiment,by using the operational modular imaging spectrometer (OMIS) II HRS im...     

选择双波长光度法测定环境水中微量成份

本文依据成份显色液在某一波长范围其吸收光谱与悬浊液光谱曲线的平行性研究测定微量成份新方法,称选择双波长光度法,该方法计算曲线稳定,基本不受环境条件影响。通过对NH_3-N,Fe、Cr(Ⅵ)、S~(2-)、NO_3~--N、PO_4~(3-)等成份测定,结果满意。该原理和方法适合于天然水,生活污水和工业废水等监测。     

Selective degradation of lignin and elimination of HO radicals in pulps by O_3 and UV laser flash irradiation

HO radical is an aggressive reagent to abstract hydrogen from diverse substitutes and lead them to degradation, however, in reaction of active oxygen species with lignins, complex phenolic polymers, in dispersed lignocellulose such as pulp for environment-benign delignification, HO radicals should be eliminated as more as possible to prevent cellulose from unfavorably concomitant degradation. A reaction system of O3 is constructed under UV laser flash irradiation, and HO radicals are controlled efficiently by it. A new mechanism is proposed, for the first time, that O radicals generated from reaction of O3 with UV laser flash irradiation might be the contributor to scavenge HO radicals.     

基于细胞膜表面电势探讨Ca与毒性离子在植物根膜表面的相互作用

有毒重金属离子的自由离子活度已被广泛认为是重金属最直接的活性形态,可以用来预测重金属的生物效应,而事实上生物体表的重金属离子浓度由于细胞表面膜电势的静电效应而与本体溶液中重金属的自由离子活度存在显著差异.细胞膜表面电势随溶液中离子组成变化而发生变化,本体介质中钙离子能通过电荷屏蔽和离子键结合来降低膜表面电势的电负性,从而减少阳离子如Al3+、Cu2+和Ni2+在膜表面的活度,增加阴离子如SeO42-和H2AsO4-在膜表面的活度,这种电负性降低的程度能通过Gouy-Chapman-Stern模型来量化.基于植物根表重金属离子活度可以更好地预测其生物效应.细胞膜表面电势为研究离子之间交互作用机制及其与植物效应之间的关系提供了一个全新的角度.     

Sorption of norfloxacin from aqueous solutions by activated carbon developed from Trapa natans husk

The low-cost activated carbon was prepared from a renewable aquatic plant residue,Trapa natans husk,and tested for its ability to remove norfloxacin (NOR) from aqueous solutions. Physical and chemical properties of the Trapa natans husk activated carbon (TAC) were characterized. TAC has a large surface area of 1274 m2/g and mesoporous structure. Carboxylic and hydroxyl groups contributed to the sorption of NOR onto TAC but they were not the most important factors in the sorption process. The rates of adsorp...     

Porous zinc(Ⅱ)-organic framework with potential open metal sites:Synthesis,structure and property

Reaction of Zn(NO3)2.6H2O with 5-(isonicotinamido) isophthalic acid(H2INAIP) in N,N-dimethylformamide(DMF) affords a new three-dimensional(3D) coordination polymer {[Zn(INAIP)(DMF)].0.5DMF.4H2O}n(1).The X-ray crystallographic structural analysis reveals that complex 1 is a 3D porous framework containing a potential open metal site inside the pores.Topology analysis confirms that complex 1 is a two-fold interpenetrated(10,3)-b net with both metal ion and ligand acting as 3-connecting nodes.The thermal stabil...