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Adsorption and Insecticidal Activity of Toxin from Bacillus thuringiensis on Rectorite

Pedosphere 2007年第4期17卷 513-521页

作者： ZHOU Xue-Yong HUANG Qiao-Yun CAI Peng YU Zi-Niu Hubei Province Key Laboratory of Refractories and Ceramics Wuhan University of Science and Technology Wuhan 430081 （China）. College of Biotechnology and chemical engineering Tianjin University of Technology Tianjin 300191 （China） State Key Laboratory of Agricultural Microbiology College of Resources and Environment Huazhong Agricultural Uni- versity Wuhan 430070 （China）

The adsorption and desorption of the toxin from Bacillus thuringiensis strain WG-001 on rectorite were studied at different toxin and/or rectorite concentrations, pH values and temperatures. The insecticidal activity of the adsorbed toxin was evaluated by determining the lethal concentration to kill 50% of the larvae of Heliothis armigera （LC50）. The adsorption of the toxin on rectorite in sodium carbonate buffer （pH 9） reached equilibrium within 0.5-1.0 h and the adsorption isotherm of the toxin followed the Langmuir equation （R^2 〉 0.99）. In the pH range from 9 to 11 （carbonate buffer）, the adsorbed toxin decreased with increasing pH. The adsorption amounts decreased with increasing rectorite：toxin ratio. The adsorption was not significantly affected by the temperature between 10 and 50 ℃. The X- ray diffraction analysis indicated occurrence of the intercalation of the rectorite by the toxin. The infrared absorption spectrum showed that the binding of the toxin did not alter its structure. The LC50 wlues of the adsorbed toxin were smaller than those of the free toxin. The rectorite protected the toxin from ultraviolet irradiation damage. The desorption of the adsorbed toxin in water ranged from 37.5% to 56.4% and from 27.4% to 41.8% in a carbonate buffer. The desorption percentage also decreased with increasing rectorite：toxin ratio.

关键词： Bacillus thuringiensis insecticidul uctivity rectorite toxin udsorption und desorption

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Pathways of birnessite formation in alkali medium

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Science china Earth Sciences 2005年第9期48卷 1438-1451页

作者： FENG Xionghan1, TAN Wenfeng1, LIU Fan1, HUANG Qiaoyun1 & LIU Xiangwen2 1. College of Resources and environment, Huazhong Agricultural university, Wuhan 430070, china 2. Testing Center, china university of Geosciences, Wuhan 430074, china 1. College of Resources and environment Huazhong Agricultural University 430070 Wuhan China 2. Testing Center China University of Geosciences 430074 Wuhan China

Birnessite is a common weathering and oxidation product of manganese-bearing rocks. An O2 oxidation procedure of Mn(OH)2 in the alkali medium has been used to synthesize birnessite. Fast and powder X-ray diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), energy dispersed X-ray analysis (EDAX), infrared spectroscopy (IR) techniques and chemical composition analysis, Eh-pH equilibrium diagram approaches were employed to investigate the reaction process and pathways of birnessite formation. Results showed that the process of the birnessite formation could be divided into four stages: (1) forma- tion stage for hausmannite and feitknechtite, (2) stage of transformation of hausmannite and feitknechtite to buserite, (3) buserite crystal growing stage, and (4) stage of conversion of buser- ite into birnessite. Mn(OH)2 was mainly present as amorphous state only for a short initial time of oxidation reaction. In the oxidation process, buserite formed following two pathways by recrys- tallization after dissolution of the intermediates, and the transformations of the minerals de- pended on the Eh determined by the dissolved O2 concentration on their surfaces. The results are fundamental in further exploration on the mechanism of birnessite formation in the alkali medium. A great practical significance would also be expected with respect to the areas of mate- rial sciences.

关键词： birnessite, pathway of formation, reaction process, Eh-pH diagram, hausmannite, feitknechtite.

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MICROSCOPIC　CHARACTERISTICS　AND　ORIGIN　OF　PELLETOID　KAOLINITE　ROCK　IN　THE　XIASHIHEZHI　FORMATION，HUAINAN　COALFIELD，ANHUI　PROVINCE，EAST　china

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Scientia Geologica Sinica 1994年第1期 51-57页

作者： Liu Qinfu Zhang Pengfei and Yang Xiaojie(beijing Graduate school, china university of mining and technology)

ＭＩＣＲＯＳＣＯＰＩＣＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＡＮＤＯＲＩＧＩＮＯＦＰＥＬＬＥＴＯＩＤＫＡＯＬＩＮＩＴＥＲＯＣＫＩＮＴＨＥＸＩＡＳＨＩＨＥＺＨＩＦＯＲＭＡＴＩＯＮ，ＨＵＡＩＮＡＮＣＯＡＬＦＩＥＬＤ，ＡＮＨＵＩＰ... 详细信息

ＭＩＣＲＯＳＣＯＰＩＣＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＡＮＤＯＲＩＧＩＮＯＦＰＥＬＬＥＴＯＩＤＫＡＯＬＩＮＩＴＥＲＯＣＫＩＮＴＨＥＸＩＡＳＨＩＨＥＺＨＩＦＯＲＭＡＴＩＯＮ，ＨＵＡＩＮＡＮＣＯＡＬＦＩＥＬＤ，ＡＮＨＵＩＰＲＯＶＩＮＣＥ，ＥＡＳＴＣＨＩＮＡ...

关键词： ROCK KAOLINITE THE XIASHIHEZHI PELLETOID EAST AND

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Synthesis and photoluminescence property of red phosphors LiEu_(1-x)Y_x(WO_4)_(0.5)(MoO_4)_(1.5) for white LED

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Science china(Technological Sciences) 2009年第7期52卷 1913-1918页

作者： XIE An, YUAN XiMing, WANG JuanJuan & WANG Feng engineering Research Center of Nano-Mineral Materials and Application, Ministry of Education, Faculty of Materials Science and chemical engineering, china university of Geosciences, Wuhan 430074, china 1. engineering Research Center of Nano-Mineral Materials and Application Ministry of Education Faculty of Materials Science and Chemical Engineering China University of Geosciences Wuhan 430074 China

A series of novel red phosphors LiEu1-xYx(WO4)0.5(MoO4)1.5 (x=0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.8) were synthesized by conventional solid state reaction method with the starting materials: WO3, MoO3, Eu2O3, Li2CO3 and Y2O3. The spectrum and the crystal structure of the phosphors were characterized by F-4500 and XRD respectively. Meanwhile the effects of flux and Y3+ concentration on the crystal structure and luminescent properties of the phosphors were investigated. The results showed that the optimal content of flux (WAlF3/WH3BO3=1/1) was 1 wt% and the optimal doping concentration of Y3+ was 0.5 mol. The emission spectrum showed the most intense peak was located at 615 nm, which corresponds to the 5D0→7F2 transition of Eu3+ and that Eu3+ occupied the lattice site of noncentrosymmetric environment in the scheelite phases. The excitation spectrum displayed that these phosphors could be effectively excited by ultraviolet (UV) (396 nm) and blue (466 nm) light, nicely in correspondence with the widely ap- plied output wavelengths of ultraviolet or blue LED chips. The influence of flux on the luminescent properties of LiEu0.5Y0.5(WO4)0.5(MoO4)1.5 phosphor was analyzed. The XRD spectra indicated that the flux could help to crystallize the phosphor, and no other phases were formed except the tetragonal. When adding flux, the relative intensity of LiEu0.5Y0.5(WO4)0.5(MoO4)1.5 became much stronger and the average particle size of the phosphor decreased.

关键词： red emitting phosphor LiEu1-xYx(WO4)0.5(MoO4)1.5 flux white LED

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Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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Science china Earth Sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2, TONG Jinnan3, QIU Haiou4 & ZHAO Laishi3 1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china 2. Henan Institute of Geological Survey, Zhengzhou 450007, china 3. State Key Laboratory of Geological Processes and Mineral Resources at china university of Geosciences, Wuhan 430074, china 4. Faculty of Material Sciences and chemical engineering, china university of Geosciences, Wuhan 430074, china 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan Institute of Geological Survey Zhengzhou 450007 China 3. State Key Laboratory of Geological Processes and Mineral Resources at china university of Geosciences Wuhan 430074 China 4. Faculty of Material Sciences and chemical engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13C background values are intensively controlled by palaeogeographic environment. In general, δ 13C values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

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Soil Heavy Metal Pollution Around the Dabaoshan Mine,Guangdong Province,china

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Pedosphere 2007年第5期17卷 588-594页

作者： ZHOU Jian-Min DANG Zhi CAI Mei-Fang LIU Cong-Qiang College of environmental Science and engineering South China University of Technology Guangzhou 510640 （China） Guangdong Key Laboratory of Agro-environment Integrated Control Guangdong Institute of Eco-Environment and Soil Science Guangzhou 510650 （China） State Key Laboratory of environment Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 （China）

Soil contamination in the vicinity of the Dabaoshan Mine, Guangdong Province, china, was studied through determi- nation of total concentrations and chemical speciation of the toxic metals, Cu, Zn, Cd, and Pb, using inductively coupled plasma mass spectrometry. The results showed that over the past decades, the environmental pollution was caused by a combination of Cu, Zn, Cd, and Pb, with tailings and acid mine drainage being the main pollution sources affecting soils. Significantly higher levels （P ≤ 0.05） of Cu, Zn, Cd, and Pb were found in the tailings as compared with paddy, garden, and control soils, with averages of 1486, 2516, 6.42, and 429 mg kg^-1, respectively. These metals were continuously dispersed downstream from the tallings and waste waters, and therefore their concentrations in the paddy soils were as high as 567, 1 140, 2.48, and 191 mg kg^-1, respectively, being significantly higher （P ≤ 0.05） as compared with those in the garden soils. The results of sequential extraction of the above metals from all the soil types showed that the residual fraction was the dominant form. However, the amounts of metals that were bound to Fe-Mn oxides and organic matter were relatively higher than those bound to carbonates or those that existed in exchangeable forms. As metals could be transformed from an inert state to an active state, the potential environmental risk due to these metals would increase with time.

关键词： chemical speciation combined pollution index (CPI) contaminated soil heavy metals

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Comparison of Photochemical Reactions of m-Cresol in Aqueous Solution and in Ice

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chemical Research in Chinese Universities 2012年第1期28卷 47-52页

作者： PENG Fei1, XUE Hong-hai1, TANG Xiao-jian1,2, KANG Chun-li1, LI Lin-lin1 and LI Zhe1 1. Key Laboratory of Groundwater Resources and environment, Ministry of Education, Jilin university, Changchun 130021, P. R. china 2. school of Municipal and environmental engineering, Jilin Institute of Architecture and Civil engineering, Changchun 130118, P. R. china Jilin Univ Key Lab Groundwater Resources & Environm Minist Educ Changchun 130021 Peoples R China Jilin Inst Architecture & Civil Engn Sch Municipal & Environm Engn Changchun 130118 Peoples R China

We compared the photochemical reaction of m-cresol containing ·OH precursors such as H2O2, NO2 and NO3 in aqueous solution with those in ice. The results show that the conversion rate of m-cresol in aqueous solution was higher than that in ice. H2O2, NO2 and NO3 all accelerated the photoconversion of m-cresol in both aqueous solution and ice. The photochemical reactions of m-cresol obeys the first order kinetics equation. According to the photoproducts identified by GC-MS, we proposed that hydroxylation and nitration reactions occurred in both aqueous solution and ice. Coupling reaction was common in ice, however, in aqueous solution it was found only in UV system. Our results suggest that the photochemical reactions of m-cresol were different in aqueous solution and in ice.

关键词： m-Cresol Photochemistry Aqueous solution Ice Mechanism

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Endolithic fungi:A possible killer for the mass extinction of Cretaceous dinosaurs

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Science china Earth Sciences 2008年第6期51卷 801-807页

作者： GONG YiMing1,2, XU Ran1 & HU Bi2 1 Key Laboratory of Biogeology and environmental Geology of Ministry of Education, State Key Laboratory of Geological Processes and Mineral Resources, china university of Geosciences, Wuhan 430074, china 2 Institute of Resources and environment Key Laboratory of Biogenic Traces & Sedimentary Minerals of Henan Province, Henan Polytechnic university, Jiaozuo 454003, china 1. Key Laboratory of Biogeology and environmental Geology of Ministry of Education State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 2. Institute of Resources and environment Key Laboratory of Biogenic Traces & Sedimentary Minerals of Henan Province Henan Polytechnic University Jiaozuo 454003 China

Mycelium-like structures found under ESEM within radial sections of fragmental dinosaur eggshells would be the endolithic fungi coexistent with dinosaur eggs in the upper part of the Late Cretaceous Hugang Formation from the Wenjiaping section of Wenxian, Danjiangkou, northwestern Hubei, Central china. The endolithic fungi selectively occurred in the bad biomineral zone within the columnar layer of the eggshells, where the crowded endolithic fungi penetrated the columnar layer at near-vertical or near-horizontal angles. The endolithic fungi are needle-like, ribbon-like and silk-like, and 5–18 μm long, 0.3–0.5 μm wide at their base, with pointed tip, and are unbranched. The hyphae are mainly composed of oxygen, carbon and calcium, and are with minor sodium, potassium, chlorine and sulfur. The endolithic fungi and host have the same characters in lithification, fracture and main chemical composition. We suggested that the episode endolithic fungi invading dinosaur eggs may have taken place in the interval between after formation of dinosaur eggshells and before their petrification and that dinosaur eggs invaded by endolithic fungi would not be normally incubated or would only be incubated into venerable and pathologic baby dinosaurs to be easily to aborted and contributed to the mass extinction of the dinosaurs at the end of Cretaceous.

关键词： endolithic fungi dinosaur eggs mass extinction Cretaceous

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A New Soil Infiltration technology for Decentralized Sewage Treatment:Two-Stage Anaerobic Tank and Soil Trench System

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Pedosphere 2008年第3期18卷 401-408页

作者： YE Chun HU Zhan-Bo KONG Hai-Nan WANG Xin-Ze HE Sheng-Bing school of environmental Science and engineering Shanghai Jiaotong University Shanghai 200230 （China） school of Light Industry and Food engineering Guangxi University Nanning 530004 （China） Research Center of Lake Ecological environment Chinese Research Academy of Environmental Sciences Beijing 100012（China）

The low removal efficiency of total nitrogen （TN） is one of the main disadvantages of traditional single stage subsurface infiltration system, which combines an anaerobic tank and a soil filter field. In this study, a full-scale, two-stage anaerobic tank and soil trench system was designed and operated to evaluate the feasibility and performances in treating sewage from a school campus for over a one-year monitoring period. The raw sewage was prepared and fed into the first anaerobic tank and second tank by 60% and 40%, respectively. This novel process could decrease chemical oxygen demand with the dichromate method by 89%-96%, suspended solids by 91%-97%, and total phosphorus by 91%-97%. The denitrification was satisfactory in the second stage soil trench, so the removals of TN as well as ammonia nitrogen （NH4^＋-N） reached 68%-75% and 96% 99%, respectively. It appeared that the removal efficiency of TN in this two-stage anaerobic tank and soil trench system was more effective than that in the single stage soil infiltration system. The effluent met the discharge standard for the sewage treatment plant （GB18918-2002） of china.

关键词： decentralized treatment nitrogen removal soil trench system subsurface infiltration

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The Entropies Evaluation of the High-entropy System and its Determination of Operating Entropy

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Systems Science and Systems engineering 2000年第3期10卷 315-323页

作者： SONG Hua\|ling\+1,\ ZHAI Cong\|min 2,\ LIU Li\|juan 21.school of management, Hebei university of technology Cornelis Reiman, Tianjin 300130, china Department of Management, Monash university, Australia 2.school of management, Hebei university of T

This article applies the basic principles of the general and special entropy, puts forward the concept of High\|entropy system and its entropies. Sometimes, the entropy functions have been defined, and their mathematical models have been constructred, and methods of quantification. Specially. Taking the mining System as an example, the quantification method of the operating entropy is given under the synthetic action of the man\|made entropy, machine entropy, natural entropy and environmnet entropy. Therefore it enriches the theoretical and applied systems of the general and special entropy.

关键词： general and special entropy theories high\|entropy system operating entropy manmade entropy natural entropy environment entropy

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