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Frontiers of Earth Science 2017年第2期11卷 397-406页

作者： Hongfen ZHU Rutian BI Yonghong DUAN Zhanjun XU College of resource and environment Shanxi Agricultural University Shanxi 030801 China

Understanding scale-and location-specific variations of soil nutrients in cultivated land is a crucial consideration for managing agriculture and natural resources effectively. In the present study, wavelet coherency was used to reveal the scale-location specific correlations between soil nutrients, including soil organic matter （SOM）, total nitrogen （TN）, available phosphorus （AP）, and available potassium （AK）, as well as topo- graphic factors （elevation, slope, aspect, and wetness index） in the cultivated land of the Fen River Basin in Shanxi Province, China. The results showed that SOM, TN, AP, and AK were significantly inter-correlated, and that the scales at which soil nutrients were correlated differed in different landscapes, and were generally smaller in topographically rougher terrain. All soil nutrients but TN were significantly influenced by the wetness index at relatively large scales （32-72 km） and AK was significantly affected by the aspect at large scales at partial locations, showing localized features. The results of this study imply that the wetness index should be taken into account during farming practices to improve the soil nutrients of cultivated land in the Fen River Basin at large scales.

关键词： soil nutrients wavelet coherency wetness index spatial variation cultivated land

Variation of peroxidase isoenzyme and biofilm of Phanerochaete chrysosporium in continuous membrane bioreactor for Reactive Brilliant Red X3-B treatment

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Journal of environmental Sciences 2009年第7期21卷 940-947页

作者： GAO Shang, CHEN Cheng, TAO Fang, HUANG Minsheng, MA Lihua, WANG Zhonghua, WU Linhui School of resource and environment Science, East China Normal University, Shanghai 200062, China. School of resource and environment Science East China Normal University Shanghai 200062 China

The influence of a Reactive Brilliant Red X-3B （RBR X-3B） dye on the peroxidase isoenzyme ofPhanerochaete chrysosporium was determined, and the biofilm structure in a white rot fungal continuous membrane bioreactor （MBR） was also investigated by scanning electron microscope （SEM）. The variation of peroxidase isoenzyme and the decolorization rate in the continuous MBR were evaluated. The results showed that the 100 mg/L RBR X-3B could stimulate the production of the peroxidase isoenzyme in the shaking-flask culture. In addition, two new peroxidase isoenzyme bands with relative mobility （Rf） value of 0.27 and 0.28 appeared, but the activity was lower than the blank control of 11 d. In the continuous MBR, the system worked stably during the first 60 d, the main peroxidase isoenzyme bands existed and three new bands with Rf value of 0.10, 0.27, and 0.28 appeared. Meanwhile, the biofilm grew well and the average decolorization rate could reach 90.6%. But the bands of peroxidase isoenzyme decreased rapidly at day 65, only two bands with Rf value 0.24 and 0.26 existed, and the decolorization rate decreased to 78.3%. Therefore, 5 bottles of P. chrysosporium mycelial pellet were added into the MBR, and then the activity of the peroxidase isoenzyme and the decolorization rate had a slight recovery. Finally, the decolorization rate finally decreased to 75.2%. These results contribute to a comprehensive understanding of the variation of peroxidase isoenzyme and biofilm in continuous MBR by white rot fungi.

关键词： Phanerochaete chrysosporium continuous membrane bioreactor Reactive Brilliant Red X3-B peroxidase isoenzyme pattern

Ultrasound enhanced heterogeneous activation of peroxydisulfate by bimetallic Fe-Co/GAC catalyst for the degradation of Acid Orange 7 in water

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Journal of environmental Sciences 2014年第6期26卷 1267-1273页

作者： Chun Cai Liguo Wang Hong Gao Liwei Hou Hui Zhang department of environmental Engineering Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory Wuhan University

Bimetallic Fe-Co/GAC （granular activated carbon） was prepared and used as heterogeneous catalyst in the ultrasound enhanced heterogeneous activation of peroxydisulfate （PS, S2O8 2-） process. The effect of initial pH, PS concentration, catalyst addition and stirring rate on the decolorization of Acid Orange 7 （AO7） was investigated. The results showed that the decolorization efficiency increased with an increase in PS concentration from 0.3 to 0.5 g/L and an increase in catalyst amount from 0.5 to 0.8 g/L. But further increase in PS concentration and catalyst addition would result in an unpronounced increase in decolorization efficiency. In the range of 300 to 900 r/min, stirring rate had little effect on AO7 decolorization. The catalyst stability was evaluated by measuring decolorization efficiency for four successive cycles.

关键词： Fe-Co/GAC ultrasound heterogeneous catalysis peroxydisulfate sulfate radicals

Preparation and Properties of PBXs Based on FOX-7 in Controlled Fragmentation Warhead Application

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含能材料 2018年第10期26卷 843-849页

作者： Karim K Elsharkawy Lin Guo Ahmed M Enew School of chemistry and environment Beijing University of Aeronautics and Astronautics Chemical department Faculty of EngineeringCairo University

Polymer bonded explosive(PBX)formulations were successfully prepared in the laboratory scale containing 1,1-diamino-2,2-dinitroethene(FOX-7)and hexogen(RDX)as brisant high explosives and different binder types of polyurethane(PU)based on glycidyl azide polymer(GAP) and hydroxyl-terminated polybutadiene(HTPB) as an energetic and inert polymeric binder *** technique was used for the preparation of different PBX formulations based on FOX-7/RDX and PU(GAP/HTPB)with 14% *** sensitivity to different initial impulses and performance characteristics of the explosive and lethal zone of the tested controlled fragmentation warhead by the fragmentation warhead assessment test(arena test)were studied,in which the arena test was carried out with a controlled fragmentation warhead made from Ck45 steel,with dimensions(100 mm length,30 mm outer diameter and 3 mm thickness).Results show that PBXGF4 has lower sensitivity to impact and heat than those of PBXGR4 by 188.4% and 3.2% *** friction sensitivity is the same as that of *** has better performance,in which detonation velocity increases by 2.1% and brisance increases by 0.5% when compared with those of *** was concluded that PBXGF4 which based on FOX-7 bonded with PU/GAP matrix has good characteristics as PBX,specially in the sensitivity to impact and can be applied for replacing PBXs based on RDX in the advanced PBXs for low sensitive fragmentation warheads.

关键词： polymer bonded explosive(PBX) controlled fragmentation warhead 1,1-diamino-2,2-dinitroethene(FOX-7) hexo-gen(RDX) preparation sensitivity performance characterization arena test

Successful preparation of BaCo_(0.5)Fe_(0.5)O_(3–δ)cathode oxide by rapidly cooling allowing for high-performance proton-conducting solid oxide fuel cells

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Journal of Advanced Ceramics 2023年第3期12卷 587-597页

作者： Yanru Yin Yanbin Zhou Yueyuan Gu Lei Bi School of resource environment and Safety Engineering University of South ChinaHengyang 421001China

A pure phase BaCo_(0.5)Fe_(0.5)O_(3–δ)(BCF),which cannot be obtained before,is successfully prepared in this study by using the calcination method with a rapid cooling *** successful preparation of BCF allows the evaluation of this material as a cathode for proton-conducting solid oxide fuel cells(H-SOFCs)for the first *** H-SOFC using the BCF cathode achieves an encouraging fuel cell performance of 2012 mW·cm–2 at 700,two℃-fold higher than that of a similar cell using the classical high-performance Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3–δ)(BSCF)***-principles calculations reveal the mechanism for the performance enhancement,indicating that the new BCF cathode significantly lowers the energy barriers in the oxygen reduction reaction(ORR)compared with the BSCF ***,improved cathode performance and fuel cell output are obtained for the BCF *** fuel cell using the BCF cathode also shows excellent long-term stability that can work stably for nearly 900 h without noticeable *** fuel cell performance and long-term stability of the current BCF cell are superior to most of the H-SOFCs reported in previous reports,suggesting that BCF is a promising cathode for H-SOFCs.

关键词： BaCo_(0.5)Fe_(0.5)O_(3–δ) cathode proton conductor solid oxide fuel cells(SOFCs)

Theoretical Researches on the Recognizing Characteristics of Atrazine Imprinted Polymers with Different Functional Monomers

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Chinese Journal of Structural chemistry 2012年第12期31卷 1794-1802页

作者：刘俊渤孙佳妮唐珊珊陈凯尹靳瑞发 College of resource and environmental Science Jilin Agricultural University department of chemistry Chifeng University

As a widely used herbicide, the threat of atrazine to both environment and health of people has become the focus. Therefore, the research and analysis of atrazine are getting more important. In this work, the MIT was used to detect atrazine theoretically. Atrazine was taken as a template molecule. MAA, MMA and TFMAA were taken as the functional monomers, respectively. The geometry optimization, the nature of hydrogen bonds, the NBO charge, and the binding energies of the imprinted molecule with the functional monomers were investigated at the B3LYP/6-31g（d,p） level. Results indicated that atrazine had the strongest interaction with TFMAA. When the ratio of atrazine and TFMAA was 1：6, the amount of H-bond formed from atrazine and TFMAA was the largest. Moreover, TFMAA owned the largest binding energy with atrazine while MMA owned the smallest. The study is helpful to interpret experiment phenomena of molecular imprinting and select better functional monomers.

关键词： atrazine molecular-imprinted polymer hydrogen bonds density functional theory

Determination of optimum nitrogen application rates in Zhejiang Province, China, based on rice yields and ecological security

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Journal of Integrative Agriculture 2015年第12期14卷 2426-2433页

作者： LI Yan CHEN Yi WU Chun-yan TANG Xu JI Xiao-jiang Institute of environment resource and Soil Fertilizer Zhejiang Academy of Agricultural Sciences

Excessive nitrogen（N） fertilization in intensive agricultural areas such as the plain region of South China has resulted in low nitrogen use efficiency and serious environmental problems. To determine the optimum N application rate, grain yield, apparent nitrogen recovery efficiency（ANRE）, apparent N loss, and ammonium（NH_3） volatilization under different N application rates in the three years from 2012 to 2014 were studied. The results showed that the relationship between grain yields and N application rate in the three years were well fitted by quadratic equations. When N application rate reached 197 kg ha^（–1） in 2012, 199 kg ha^（–1） in 2013 and 196 kg ha^（–1） in 2014, the plateau of the grain yields appeared. With the increase of N application rate, the ANRE for rice decreased which could be expressed with sigmoidal equation; when N application rate was 305 kg ha^（–1） in 2012, 275 kg ha^（–1） in 2013 and 312 kg ha^（–1） in 2014, the curves of ANRE appeared turing points. Besides, the relationship between soil Nresidual and N application rate was fitted by the quadratic equation and the maximums of soil Nresidual were reached in the three years with the N application rate of 206, 244 and 170 kg ha^（–1）, respectively. Statistical analysis indicated that NH3 volatilization and apparent N loss in three years all increased with the increasing N application rate. When the amount of NH3 volatilization increased to 11.6 kg N ha^（–1） in 2012, 40.5 kg N ha^（–1） in 2013 and 57.0 kg N ha^（–1）in 2014, the apparent N loss in the three years had obvious increase. To determine the optimum N application rate, the average N application on the plateau of the grain yield was considered as the lower limit while the average N application rate at the turning points of ANRE, the residual N in soil and apparent N loss was taken as the upper limit. According to the results in three years, the optimum N application rate for rice in Zhejiang was 197–255 kg ha^（–1）.

关键词： optimum nitrogen application rate Zhejiang rice yields ecological security

Improved performance and prolonged lifetime of titania-based materials: sequential use as adsorbent and photocatalyst

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Science China chemistry 2015年第7期58卷 1211-1219页

作者： Yan Peng Minghui Li Shujuan Zhang Guangze Nie Meng Qi Bingcai Pan State Key Laboratory of Pollution Control and resource Reuse School of the environment Nanjing University

Lifetime is a key index in the evaluation of environmentally functional materials. Although it is well known that adsorption is the first step in photocatalysis, very little work has been done on the sequential use of materials as both adsorbents and photo- catalysts. In this work, two titania-based materials, TiO2 xerogel and TiO2 photocatalyst nanoparticles, were fabricated and evaluated as adsorbent and photocatalyst for the remediation of contaminated water with an azo dye, Acid Orange 7 （AO7）, as the modeling pollutant. The TiO2 xerogel showed a high adsorption capacity to AO7 （769 mg/g） and could be regenerated eas- ily with diluted NaOH solution （0.01 mol/L） for several cycles. The exhausted xerogel was calcined at 400 ℃ for 3 h and used as a photocatalyst for the degradation of AO7. Compared to the nanoparticles directly prepared from fresh TiO2 xerogel, the TiO2 nanoparticles from adsorption exhausted xerogel showed a much higher photocatalytic activity upon both UV and visible light irradiation. Thus the titania-based materials were endowed with improved performance as well as prolonged lifetime.

关键词： titanium dioxide adsorbent reuse photocatalyst azo dye

Synthesis,Crystal Structure and Quantum chemistry of the Complex [Cu(p-FBA)_2(phen)(H_2O)]

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Chinese Journal of Structural chemistry 2010年第10期29卷 1587-1592页

作者：季宁宁石智强赵仁高 department of chemistry and environment Science Taishan University department of Materials Science and Chemical Engineering Taishan University

A novel metal-organic complex Cu（p-FBA）2（phen）（H2O）（p-FBA = p-fluorobenzoic acid,phen = 1,10-phenanthroline） has been synthesized and structurally characterized by X-ray single-crystal diffraction,elemental analysis and IR spectra. The crystal belongs to triclinic,space group P1 with a = 7.8043（7）,b = 10.4069（9）,c = 14.3658（13） ,α = 105.3170（10）,β = 96.877（2）,γ = 96.7580（10）o,V = 1103.56（17） 3,Mr = 539.96,Z = 2,Dc = 1.625 g/cm3,μ = 1.050 mm-1,F（000） = 550,the final R = 0.0324 and wR = 0.0952. In the crystal,the structure consists of discrete molecules containing a five-coordinate copper（Ⅱ ） in a distorted square pyramidal configuration. Intramolecular O-H···O hydrogen bonds,weak intermolecular C-H···O hydrogen bonds and π-π stacking link the molecules into a one-dimensional chain structure. The study on the title complex has been performed with quantum chemistry calculation by means of G03W package on the Lanl2dz basis set. The stabilities of the complex together with the orbital energies and composition characteristics of some frontier molecular orbitals have been investigated.

关键词： copper(II) complex crystal structure quantum chemistry calculation

Structure modeling of terbium doped strontium-lanthanum borate

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Journal of Rare Earths 2014年第3期32卷 248-253页

作者： A.Shyichuk S.Lis G.Meinrath department of Rare Earths Faculty of Chemistry Adam Mickiewicz University Radioactivity environment Remediation (RER) Consultants

Terbium doped strontium-lanthanum borate, Sr3La2（BO3）4：Tb （SLB）, was studied by semi-empirical computational ap- proaches using PM6 parametrization and the SPARKLE model for lanthanide（Ⅲ）（Ln（Ⅲ）） cations. The focus of interest was on structural aspects, e.g. the cell parameters and distribution of dopant ions between various sites as a function of dopant concentration. The cell linear dimensions were calculated to decrease linearly with increasing dopant molar concentration. SLB offered two sites for the dopant. Calculations predicted that one of these sites should be preferred by the Tb（Ⅲ） dopant. The optimized cell dimensions as well as the total energies differed for structures with dopant exclusively in site 1 or site 2. Computational predictions were tested against experimental results obtained for SLB synthesized by sol-gel method varying the dopant concentration. The agreement be- tween experimental and computational results was found sufficiently promising to continue the computational studies.

关键词： strontium-lanthanum borate terbium structure calculations rare earths