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Identification of secondary organic aerosols based on aerosol mass spectrometry

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中国科学：化学英文版 2010年第12期53卷 2593-2599页

作者： HUANG XiaoFeng 1,ZHAO QianBiao 1,2,HE LingYan 1,HU Min 2,BIAN QiJing 3,XUE Lian 1 & ZHANG YuanHang 2 1 Key Laboratory for Urban Habitat environmental science and Technology School of Environment and Energy,Peking university Shenzhen Graduate School,Shenzhen 518055,China 2 State Key Joint Laboratory of environmental Simulation and Pollution Control College of environmental sciences and Engineering,Peking university,Beijing 100871,China 3 Division of Environment,Hong Kong university of science & Technology,Hong Kong,China Key Laboratory for Urban Habitat environmental science and Technology School of Environment and Energy Peking University Shenzhen Graduate School Shenzhen China State Key Joint Laboratory of environmental Simulation and Pollution Control College of environmental sciences and Engineering Peking University Beijing China Division of Environment Hong Kong University of Science & Technology Hong Kong China

Secondary organic aerosol (SOA) is one of the major components of aerosols in the atmosphere and has not been well understood so *** to the complex chemical composition of organic aerosols,the identification of SOA has been a hotspot and difficult issue in the field of aerosol *** study attempts to quantitatively identify SOA in winter of Shenzhen based on positive matrix factorization (PMF) *** sources were resolved and SOA was identified subsequently according to the characteristic ion fragments measured by highly time-resolved aerosol mass spectrometer *** showed that in the winter of Shenzhen the average SOA concentration was 9.41±6.33 g/m 3,accounting for 39.9±21.8% of the total organic *** with primary organic aerosol (POA),the SOA concentrations had no large variation,suggestive of characteristics of regional secondary *** ratio of SOA/BC had pronounced diurnal variation,similar to that of O x (O3+NO2),indicating SOA formation was significantly controlled by activity of photochemistry in the *** most effective period for SOA formation was from 9 am～3 pm since the SOA/BC ratio increased by 122% during this *** study provides a new technical method and a new idea for SOA investigation.

关键词： secondary organic aerosol aerosol mass spectrometry positive matrix factorization (PMF)

Changes of microbial community structures and functional genes during biodegradation of phenolic compounds under high salt condition

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Journal of environmental sciences 2009年第6期21卷 821-826页

作者： WANG Ping,QU Yuanyuan,ZHOU Jiti School of environmental and Biological science and Technology,Dalian university of Technology,Dalian 116024,China. School of environmental and Biological science and Technology Dalian University of Technology Dalian 116024 China

The changes of microbial community structures and functional genes during the biodegradation of single phenol and phenol plus p-cresol under high salt condition were *** was found that the phenol-fed system（PFS） exhibited stronger degrading abilities and more stable biomass than that of the phenol plus p-cresol-fed system（PCFS）.The microbial community structures were revealed by a modern DNA fingerprint technique,ribosomal intergenic spacer analysis（RISA）.The results indicated that the microbial community of PFS changed obviously when gradually increased phenol concentration,while PCFS showed a little change.16S rRNA sequence analysis of the major bands showed that Alcanivorax *** was predominant species during phenolic compounds ***,amplified functional DNA restriction analysis（AFDRA） on phenol hydroxylase genes showed that the fingerprints were substantially different in the two systems,and the fingerprints were not the same during the different operational periods.

关键词： phenolic compounds high salt phenol hydroxylase ribosomal intergenic spacer analysis amplified functional DNArestriction analysis

Geochemistry of Trace and Rare Earth Elements in Red Soils from the Dongting Lake Area and Its environmental Significance

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Pedosphere 2009年第5期19卷 615-622页

作者： MAO Long-Jiang MO Duo-Wen YANG Jing-Hong SHI Chen-Xi College of Atmospheric science Nanjing University of Information Science & Technology Nanjing 210044 (China) College of Urban and environmental sciences Peking University Beijing 100871 (China) department of Earth sciences Nanjing University Nanjing 210093 (China)

Trace element(TE) and rare earth element(REE) contents in red soils from the Dongting Lake area of China were determined to understanding the provenance and weathering characteristics of the red *** results showed similar REE distribution patterns among red soils from the Dongting Lake area,Xiashu loess from Zhenjiang,loess and Pliocene red soil from the Loess *** patterns implied a similar provenance from dust-storms,except for red soil R5 which formed by bedrock weathering and had significant light REE(LREE) enrichment and heavy REE(HREE) depletion due to longer weathering periods and higher intensity of *** element,especially the Rb/Sr and Li/Ba ratios,and REE,especially the LREE/HREE ratio and δEu could trace weathering *** Rb/Sr,Li/Ba,and LREE/HREE ratios and negative Eu anomalies were present in the red soils from the Dongting Lake *** weathering intensity was in the decreasing order of R5 in the Dongting Lake area > red soils from the Dongting Lake area(including reticulate red soil,weak reticulate red soil,and homogeneous red soil formed by dust storms) > Xiashu loess from Zhenjiang > loess-paleosol and Pliocene red soil from the Loess *** in the TE and REE contents of soil could be effectively used to study the provenance and the weathering intensity.

关键词： Hunan Province provenance sedimentary processes weathering intensity

Physicochemical and microbiological effects of biosurfactant on the remediation of HOC-contaminated soil

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Progress in Natural science:Materials International 2005年第7期15卷 577-585页

作者： ZENG Guangming , ZHONG Hua, HUANG Guohe and FU Haiyan ( department of environmental science and Engineering, Hunan university, Changsha 410082, China Faculty of Engineering, university of Regina, Regina, Saskatoon S4S0A2, canada) department of environmental science and Engineering Hunan University Changsha 410082 China Faculty of Engineering University of Regina Regina Saskatoon S4SOA2 Canada

Remediation of soil contaminated by hydrophobia organic compounds using biosurfactants as additives involves interactions between soil matrix, hydrophobic organic compound contaminants, biosurfactants and microorganisms. In this paper, the mechanism for biosurfactants to enhance the contaminant degradation is basically revealed. Biosurfactants can enhance solubilization of the contaminants in the soil matrix, change their mass transfer properties into the aqueous phase, as well as affect their sorption properties. Furthermore, biosurfactants can act on microorganisms and change their surface properties, accordingly cause new growth and uptake behavior of the bacteria in the soil matrix. Both the physicochemical and the microbiological effects can basically increase the bioavailability of the contaminants and enhance their degradation.

关键词： bioavailability physicochemical effects microbiological effect hydropbobic organic compounds biosurfactants.

Anisotropic Variation Law of Rock Permeability with the Burial Depth of Limestone

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 125-128页

作者： TIAN Kaiming, WAN Li and TIAN Jiping department of Water Resources and environmental science, China university of Geosciences,27 Xueyuan Road, Beijing 100083, department of Computer sciences, Guangzhou university, Guangzhou, Guangdong 510091 China Univ Geosci Dept Water Resources & Environm Sci Beijing 100083 Peoples R China Guangzhou Univ Dept Comp Sci Guangzhou 510091 Guangdong Peoples R China

Permeability tensors of both macrofracture and microfracture Systems weremeasured progressively along the depth of limestone formations at severed sites. It was found thatthe principal permeability values K_x, K_y and K_z in these permeability tensors all decreasesimultaneously and logarithmically with depth. However, the limestone aquifers are composed of anupper region where the larger permeability ellipsoid is upright or prolate and characterized byK_z>K_x and K_z>K_y, a transitional zone, and a lower zone whose smaller permeability ellipsoid ishorizontal or oblate and characterized by K_z>K_x and K_z>K_y. The inversion of the permeabilityellipsoids in direction indicates that the anisotropy of rock permeability with the depth oflimestone formations has evidently changed. The anisotropic variation law of permeability tensors ina macrofracture system displays a similar pattern with that in a microfracture system. It is nextto impossible to examine the rock permeability tensor of the aquifer just by measuring the hydraulicparameters of macrofracture system directly, unless the limestone aquifer is exposed on or near theearth's surface. Therefore, the permeability tensors of a macrofracture system at any depth may beindirectly and roughly determined from the gaugeable permeability tensors of the microfracturesystem by conversion. This anisotropic variation law of rock permeability with depth is of greatsignificance in the study of three-dimensional fracture water flow the huge carbonate formations andin the research on the conditions of karst development and karst distribution.

关键词： macrofracture system microfracture system permeability tensor permeability ellipsoid

Phase transition in the Zr_(60)Al_(15)Ni_(25) bulk metallic glass subjected to rolling at room temperature

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science China(Technological sciences) 2006年第6期49卷 655-662页

作者： YAN Zhijie1, 2, LI Jinfu1, ZHOU Yaohe1 & WU Yanqing3 1. State Key Laboratory of Metal Matrix Composites, School of Materials science and Engineering, Shanghai Jiao Tong university, Shanghai 200030, China 2. School of Materials science and Engineering, Taiyuan university of science and Technology, Taiyuan 030024, China 3. School of environmental science and Engineering, Shanghai Jiao Tong university, Shanghai 200030, China State Key Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai China School of Materials science and Engineering Taiyuan University of Science and Technology Taiyuan China School of environmental science and Engineering Shanghai Jiao Tong University Shanghai China

The microstructure evolution of the Zr60Al15Ni25 metallic glass during rolling at room temperature is investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC); high-resolution transmission electron microscopy (HREM). The results show that the values of full width at half maximum (FWHM) of the XRD patterns; exothermic enthalpy ΔH of DSC plots do not monotonically change with the variation of deformation degrees . As is not large than 20%, the values of FWHM; ΔH are lower than that of the as-cast state. When reaches 30%, the values of FWHM; ΔH become larger than that of the as-cast state, while their values begin to decrease again as reaches about 85%. These results indicate that the reversible transitions between ordered; disordered atomic configurations occur during rolling, which is further verified by the HREM images. The reversible phase transition can be explained by the competition between the diffusion controlled reordering; shear-induced disordering during rolling.

关键词： metallic glasses, plastic deformation, phase transformations, shear bands.

A BATCH ARRIVAL RETRIAL QUEUE WITH STARTING FAILURES,FEEDBACK AND ADMISSION CONTROL

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Journal of Systems science and Systems Engineering 2010年第3期19卷 306-320页

作者： Jinting WANG Peng-Feng ZHOU department of Mathematics,School of science,Beijing Jiaotong university,Beijing,China department of Mathematics School of Science Beijing Jiaotong University Beijing China

This paper is concerned with the analysis of a feedback M^[X]/G/1 retrial queue with starting failures and general retrial times. In a batch, each individual customer is subject to a control admission policy upon arrival. If the server is idle, one of the customers admitted to the system may start its service and the rest joins the retrial group, whereas all the admitted customers go to the retrial group when the server is unavailable upon arrival. An arriving customer （primary or retrial） must turn-on the server, which takes negligible time. If the server is started successfully （with a certain probability）, the customer gets service immediately. Otherwise, the repair for the server commences immediately and the customer must leave for the orbit and make a retrial at a later time. It is assumed that the customers who find the server unavailable are queued in the orbit in accordance with an FCFS discipline and only the customer at the head of the queue is allowed for access to the server. The Markov chain underlying the considered queueing system is studied and the necessary and sufficient condition for the system to be stable is presented. Explicit formulae for the stationary distribution and some performance measures of the system in steady-state are obtained. Finally, some numerical examples are presented to illustrate the influence of the parameters on several performance characteristics.

关键词： Batch arrival feedback repair retrial queue starting failure

Trace metals distribution in synodontis membranaceus, sediments, Asystasia Gangetica and Platostoma Africanium from Ofuafor River around Delta Glass Factory in Ughelli North Local Government Area, Delta State Nigeria

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Journal of environmental sciences 2002年第1期14卷 79-82页

作者： NWAJEI, G.E. (Faculty of science, department of Chemistry, Delta State university, Abraka, Nigeria) Faculty of science Department of Chemistry Delta State University 尼日利亚 Abraka

The trace metals analysis in synodontis membranaceus (head and tail), bottom sediments, Asystasia Gangetica and Platostoma Africanium were carried out using atomic absorption spectrometer of model Perkin Elmer 3110. Metals analysed were copper, nickel, mangenese, chromium, iron lead and cobalt. These metals were detected in the above samples. Vegetation samples concentration in copper, manganese, chromium, iron and cobalt were higher than those obtained in bottom sediments. The tail part of the fish contents of trace metals were also higher than those of the head. The results obtained in this work exceeded the results of water analysis carried out by Omoregha on the same river. Metals such as copper, nickel, manganese and chromium were below detection limit in the water from the same river. The bioaccumulation of these trace metals in these samples were traced to activities of Delta Glass Factory.

关键词： trace metals Ofuafor River bioaccumulation of metals contamination industrial effluents Delta Glass Factory

Eco-economic evolution, emergy evaluation and policy options for the sustainable development of Tibet

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Journal of Geographical sciences 2000年第1期10卷 1-27页

作者： YAN Mao-chao, H. T. Odum ( Commission for Integrated Survey of Natural Resources, Chinese Academy of sciences, Beijing, China, Center for environmental policy, department of environmental Engineering sciences, university of Florida, Gainesville, FL, usa)

As economies and ecological support systems become more interdependent, new disciplines are needed to 'bridge the gap' of understanding between societies and nature. It is now clear that neither ecology nor economics alone can address the problems of our global commons. New measures of wealth, of value, of contributions and production are needed that acknowledge the 'natural capital' and 'ecosystem services' provided from healthy environments. A new interface is now being recognized termed 'eco-economics'. It is an ambitious and necessary attempt to understand the affairs of humanity and nature as a single, interdependent system. New tools are being invested to measure wealth. services and production fairly and equitably. In this report we use systems analysis approach to study the combined ecological-economic system of Tibet We use an alternative measure of value, based on real contributions to system performance, termed EMERGY, spelt with an 'M'. It is an accounting unit of total contributions, direct and indirect. used in generating a product or service. It is a concept derived from understanding whole systems, their interactions and interdependence, and the resources driving and maintaining them. This broader approach will help us to investigate Tibetan resources utilization and potentialities and exchange. Emergy analysis allows comparison and incroporation of environmental costs and benefits with variables of traditional economic costs and benefits to provide a more comprehensive perspective for public policy directives. Through this research, we think: 1) China has made a great effort in making Tibet develop from a closed regional system to a more and more opened regional system which is very important to the sustainable development of Tibet. 2) The increase of economic development and population growth has a close relationship with the total emergy storage and use in transportation. Education in modern science and technology increased the shared emergy of Ti

关键词： emergy eco-economic evolution sustainable development