检索结果-内蒙古大学图书馆

Effects of culture conditions on ligninolytic enzymes and protease production by Phanerochaete chrysosporium in air

Journal of environmental Sciences 2008年第1期20卷 94-100页

作者： XIONG Xiaoping WEN Xianghua BAI Yanan QIAN Yi State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental Science and Engineering Tsinghua University Beifing 100084 China.

The production of ligninolytic enzymes and protease by Phanerochaete chrysosporium was investigated under different culture conditions. Different amounts of medium were employed in free and immobilized culture, together with two kinds of medium with different C/N ratios. Little lignin peroxidase （LIP）（〈 2 U/L） was detected in free culture with nitrogen-limited medium （C/N ratio： 56/2.2, in mmol/L）, while manganese peroxidase （MnP） maximum activity was 231 and 240 U/L in 50 and 100 ml medium culture, respectively. Immobilized culture with 50 ml nitrogen-limited medium gave the highest MnP and LiP production with the maximum values of 410 and 721 U/L separately on the day 5; however, flasks containing 100 ml nitrogen-limited medium only produced less MnP with a peak value of 290 U/L. Comparatively, carbon-limited medium （C/N ratio： 28/44, in mmol/L） was adopted in culture but produced little MnP and LiE Medium type had the greatest impact on protease production. Large amount of protease was produced due to glucose limitation. Culture type and medium volume influence protease activity corporately by affecting oxygen supply. The results implied shallow immobilized culture was a possible way to gain high production of ligninolytic enzymes.

关键词： protease culture conditions ligninolytic enzymes Phanerochaete chrysosporiurn

来源：评论

学校读者我要写书评

暂无评论

Studies of Structural and Thermodynamic Properties for Polychlorinated Thianthrenes by Density Functional Theory

引用

Chinese Journal of Structural Chemistry 2008年第10期27卷 1255-1260页

作者：刘辉孙萍柳红霞王遵尧王连生 School of Biological and Chemical Engineering Jiaxing University State Key Laboratory of Pollution Control and Resources Reuse School of the EnvironmentNanjing University

The structural and thermodynamic （PCTAs） in the ideal gas state at 298.15 K and 1.013 properties of 75 polychlorinated thianthrenes ×10^5 Pa have been calculated at the B3LYP/6- 31G＊ level using Gaussian 98 program. Based on the output data of Gaussian, the isodesmic reactions were designed to calculate standard enthalpy of formation （△fH^θ） and standard free energy of formation （△fH^θ） of PCTAs congeners. The relations of these thermodynamic parameters with the number and position of C1 atom substitution （Npcs） were discussed, and it was found that there exists high correlation between thermodynamic parameters （total energy （TE）, zero-point vibrational energy （ZPE）, thermal correction to energy （Eth）, heat capacity at constant volume （Cv^θ）, entropy （S^θ）, enthalpy （H^θ）, free energy （G^θ）, standard enthalpies of formation （△fH^θ） and standard Gibbs energies of formation （△fG^θ）） and Npcs. On the basis of the relative magnitude of their △fG^θ, the order of relative stability of PCTA congeners was theoretically proposed. In addition, the correlations between structural parameters and Npcs were also discussed. The good correlations were found between molecular average polarizability （α）, energy of the highest occupied molecular orbital （EHOMO）, molecular volume （Vm） and Npcs, and all R^2 values are larger than 0.95. Moreover, it was supposed that the isomer groups with higher toxicity should be Tri-CTA and TCTA.

关键词： polychlorinated thianthrenes density functional theory （DFT） the number and position of CI atom substitution （Npcs） structural and thermodynamic parameters relative stability

来源：评论

学校读者我要写书评

暂无评论

Biodrying of municipal solid waste with high water content by combined hydrolytic-aerobic technology

引用

Journal of environmental Sciences 2008年第12期20卷 1534-1540页

作者： ZHANG Dongqing HE Pinjing SHAO Liming JIN Taifeng HAN Jingyao State Key Laboratory of Pollution Control and Resources Reuse Key Laboratory of Yangtze River Water Environment College of Environmental Science and Engineering Tongji University Shanghai 200092 China

The high water content of municipal solid waste(MSW)will reduce the effciency of mechanical sorting,consequently unfavorable for beneficial *** this study,a combined hydrolytic-aerobic biodrying technology was introduced to remove water from *** total water removals were proved to depend on the ventilation frequency and the temporal span in the hydrolytic stage. The ventilation frequency of 6 times/d was preferable in the hydrolytic *** hydrolytic span should not be prolonged more than ...

关键词： biodrying high water content hydrolysis aeration municipal solid waste extracellular enzyme

来源：评论

学校读者我要写书评

暂无评论

Enhancement of anaerobic biodegradability of flower stem wastes with vegetable wastes by co-hydrolysis

引用

Journal of environmental Sciences 2008年第3期20卷 297-303页

作者： ZHANG Bo HE Pinjing Lü Fan SHAO Liming State Key Laboratory of Pollution Control and Resources Reuse Key Laboratory of Yangtze River Water Environment College of Environmental Science and Engineering Tongfi University Shanghai 200092 China

The vegetable wastes and flower stems were co-digested to evaluate the anaerobic hydrolysis performance of difficultly biodegradable organic wastes by introducing readily biodegradable organic wastes. The experiments were carried out in batches. When the vegetable wastes were mixed with the flower stems at the dry weight ratio of 1 to 13, the overall hydrolysis rate increased by 8%, 12%, and 2% according to the carbon, nitrogen, and total solid （TS） conversion rate, respectively. While the dry weight ratio was designed as 1 to 3, there was a respective rise of 5%, 15%, and 4% in the conversion rate of carbon, nitrogen, and TS. The enhancement of anaerobic hydrolysis from the mixed vegetable wastes and flower stems can be attributed to the formation of volatile fatty acids （VFA） and nutrient supplement like nitrogen content. The maximum VFA concentration can achieve 1.7 g/L owing to the rapid acidification of vegetable wastes, loosing the structure of lignocellulose materials. The statistic bivariate analysis revealed that the hydrolysis performance was significantly related to the physical and biochemical compositions of the feeding substrate. Especially, the soluble carbon concentration in the liquid was significantly positively correlated to the concentration of nitrogen and hemicellulose, and negatively correlated to the concentration of carbon and lignocellulose in the feeding substrate, suggesting that the regulation and control of feedstock can have an important influence on the anaerobic hydrolysis of organic wastes.

关键词： municipal solid wastes hydrolysis feedstock characteristics VFA bivariate analysis

来源：评论

学校读者我要写书评

暂无评论

STUDIES ON THE ADSORPTION OF PHENOLIC COMPOUNDS ON A PS-BASED RESIN MODIFIED BY NITRO FUNCTIONAL GROUPS

引用

Chinese Journal of Polymer Science 2008年第6期26卷 713-721页

作者：李爱民 State Key Laboratory of Pollution Control andResource Reuse School of the EnvironmentNanjing University Research Center of Organic Toxic Substance Control and Resource Reuse of Jiangsu Province

A new adsorbent (JN-01) was prepared by modifying resin NDA-1800 with nitro functional *** adsorption capacities of resins XAD-4,NDA-1800 and JN-01 were investigated,and the results indicated that the modified resin JN-01 was much better in adsorbing phenol,p-nitrophenol and *** adsorption capacities of the resin JN-01 were higher than those of the resins XAD-4 and NDA-1800 within a temperature range of 283-323 K,which might be attributed to the higher surface area and the partial polarity o...

关键词： Nitro-modified Resin Adsorption Phenolic compounds.

来源：评论

学校读者我要写书评

暂无评论

Polycyclic aromatic hydrocarbon biodegradation and extracellular enzyme secretion in agitated and stationary cultures of Phanerochaete chrysosporium

引用

Journal of environmental Sciences 2008年第1期20卷 88-93页

作者： DING Juan CONG Jun ZHOU juan GAO Shixiang State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China School of the Energy and Environment Southeast University Nanjing 210096 China

The extracellular enzyme secretion and biodegradation of polycyclic aromatic hydrocarbons （PAHs） were studied in agitated and shallow stationary liquid cultures of Phanerochaete chrysosporium. Veratryl alcohol and Tween80 were added to cultures as lignin peroxidase （LIP） and manganese peroxidase （MnP） inducer, respectively. Shallow stationary cultures were suitable for the production of enzyme, whereas agitated cultures enhanced overall biodegradation by facilitating interphase mass transfer of PAHs into aqueous phases. The use of a LiP stimulator, veratryl alcohol, did not increase PAH degradation but significantly enhanced LiP activity. In contrast, Tween80 increased both MnP secretion and PAH degradation in shallow stationary cultures. On the other hand, high PAH degradation was observed in agitated cultures in the absence of detectable LiP and MnP activities. The results suggested that extracellular peroxidase activities are not directly related to the PAH degradation, and the increased solubility rather than enzyme activity may be more important in the promotion of PAH degradation.

关键词： lignin peroxidase （LIP） manganese peroxidase （MnP） Phanerochaete chrysosporium polycyclic aromatic hydrocarbons （PAHs） solubilization

来源：评论

学校读者我要写书评

暂无评论

Reactivity of ambient volatile organic compounds(VOCs) in summer of 2004 in Beijing

引用

Chinese Chemical Letters 2008年第5期19卷 573-576页

作者： Shan Huang Min Shao Sihua Lu Ying Liu State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China

Ambient volatile organic compounds （VOCs） were sampled at six sites in Beijing in the summer of 2004 and analyzed by GCMS. The chemical reactivities of 73 quantified VOCs species were evaluated by OH loss rates （LOH） and ozone formation potentials （OFPs）. Top 15 reactive species, mainly alkenes and aromatics, were identified by these two methods, and accounted for more than 70% of total reactivity of VOCs. In urban areas, isoprene was the most reactive species in term of OH loss rate, contributing 11.4% to the LOH of VOCs. While toluene, accounting for 9.4% of OFPs, appeared to have a long-time role in the photochemical processes. Tongzhou site is obviously influenced by local chemical industry, but the other five sites showed typical urban features influenced mainly by vehicular emissions.

关键词： VOC Reactivity OH loss rate Ozone formation potential

来源：评论

学校读者我要写书评

暂无评论

Vertical characteristics of the Hani terrace paddyfield ecosystem in Yunnan,China

引用

Frontiers in Biology 2008年第3期3卷 351-359页

作者： Baoshan CUI Zheyuan YOU Min YAO School of Environment Beijing Normal UniversityBeijing 100875China State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100875China

The Hani terrace paddyfield in Yunnan Province,China is categorized as a‘constructed wetland’under the Lamsar Convention *** Hani terrace paddyfield ranges from an altitude of 144 to 2000 m above sea level(ASL)in the southern slopes of the Ailao Mountains,angling down at a range of 15°to 75°.In this study,we investigated the ecosystem of the terrace paddyfields in the Mengpin and Quanfuzhuang administrative villages located at the center of the cultural heritage conservation district in the Hani terrace *** Hani terrace paddyfield ecosystem structure is"forest-village-terrace paddyfield-river"in the order of descending *** and water samples were sequen-tially taken from forests,villages and the terrace paddy-fields to be able to study the vertical characteristics of Hani’s terrace ***_(4)-P and NH_(3)-N in water were measured to test for water *** soil nutrient factors were tested,including organic material(OM),char and nitrogen ratio(C/N),pH,total nitrogen(TN),total phosphorus(TP),available phosphorus(AP),and available potassium(AK).Soil quality was also eval-uated using the characteristics of the soil nutrient *** changes in the landscape,wetland types,wetland plants,hydrology and soil nutrients were *** showed that:(1)Hani’s terrace paddyfield can be divided into five types of wetlands;the rice varieties and cultivation patterns vary in each type of wetland.(2)Hani’s terrace paddyfield has a great capacity for water conservation and a strong ability to purify *** impoundage of Hani’s terrace paddyfield is about 5050 m^(3)/hm^(2).Contaminants in the terrace paddyfield soils decrease exponentially with the decline in altitude.(3)Comparison of soil quality in five different land use types indicates decreasing soil quality from forest to terrace land to terrace paddyfield to water *** for headwater soil,single factors such as OM,TN and TP,and the comp

关键词： Hani’s terrace paddyfield wetland landscape wetland types wetland water wetland soil vertical characteristics

来源：评论

学校读者我要写书评

暂无评论

Atmospheric heterogeneous reaction of acetone:Adsorption and desorption kinetics and mechanisms on SiO_2 particles

引用

Chinese Science Bulletin 2008年第7期53卷 1004-1010页

作者： JIE ChongYu CHEN ZhongMing WANG HongLi HUA Wei WANG CaiXia LI Shuang The State Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China

Acetone plays an important role in photooxidation processes in the atmosphere. Up to date, little is known regarding the heterogeneous fate of acetone. In this study, the adsorption and desorption processes of acetone on SiO2 particles, which are the major constituent of mineral dust in the atmos-phere, have been investigated for the first time under the simulated atmospheric conditions, using in situ transmission Fourier transform infrared spectroscopy. It is found that acetone molecules are ad-sorbed on the surfaces of SiO2 particles by van der Waals forces and hydrogen bonding forces in a nonreactive and reversible state. The rates of initial adsorption and initial desorption, initial uptake coefficients and adsorption concentrations at equilibrium have been determined at different relative humidity. The presence of water vapor cannot result in the formation of new substances, but can de-crease the adsorption ability by consuming or overlapping the isolated OH groups on the surfaces of SiO2 particles. In the desorption process, a considerable amount of acetone molecules will remain on SiO2 particles in dry air, whereas acetone molecules are almost completely desorbed at a high relative humidity. In order to evaluate the role of heterogeneous reactions of acetone and other carbonyl compounds in the atmosphere, a new model fitting the atmospheric conditions is needed.

关键词：丙酮大气反射吸附作用脱附作用二氧化硅

来源：评论

学校读者我要写书评

暂无评论

Modelling the carrying capacity of urban ecosystem

Modelling the carrying capacity of urban ecosystem

引用

2nd International Conference on Bioinformatics and Biomedical Engineering, iCBBE 2008

作者： Xu, Linyu Yang, Zhifeng Li, Wei State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing China

ISBN: (纸本)9781424417483

The urban ecosystem is a Social-Economic-Natural Complex consisting of human beings and their surrounding. Because resources and environmental quality are crucial to the existence and development of an urban ecosystem, the development of an urban ecosystem is necessarily built on the basis of interactions among environmental carrying capacity (ECC), resource carrying capacity (RCC) and social-economic development capacity (SEDC). A single component's capacity should not be studied without considering the integrity of the whole system. In this paper, the concept of 'Compound carrying capacity' (CCC) is introduced and studied as an index of the interactions among ECC, RCC and SEDC, as a basis for meeting the challenges of urban sustainable development and eco-city building. Using this index, it is discussed in both theory fundamentals and quantitative models how these three kinds of capacity function to sustain the urban ecosystem. The concept of CCC is introduced to improve the comprehensive understanding of this system's structure and functions. Compared with traditional concepts, the CCC of the urban ecosystem includes the ability to develop and thus is characterized by being more dynamic. This dynamism shows in the ability of cities to respond when put under pressure. Clearly, this dynamic is not endless, both environmental, resource and social-economic development capacities have limits. A comparative study of urban ecosystems and the human immune systems shows that both systems have similar features. Thus, the CCC model is discussed in this paper in light of the biology immunity theory. In this it is assumed that the urban ecosystem is the material input and its main function is to offer eco-services. The extent of these services is dependent on both the intrinsic carrying capacity and the acquired carrying capacity of the urban ecosystem. The methodology for both calculation and adjustment mechanism of the CCC is outlined, with reference to the urban ecosystem

关键词： Sustainable development

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：