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Optimal reduction of anthropogenic emissions for air pollution control and the retrieval of emission source from observed pollutantsⅢ:Emission source inversion using a double correction iterative method

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Science China Earth Sciences 2022年第3期65卷 553-555页

作者： Qingcun ZENG lin wu Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

Using the incomplete adjoint operator method in part I of this series of papers,the total emission source S can be retrieved from the pollutant concentrationsρob obtained from the air pollution monitoring *** paper studies the problem of retrieving anthropogenic emission sources from *** that the natural source Sn is known,and as the internal source Sc due to chemical reactions is a function of pollutant concentrations,if the chemical reaction equations are complete and the parameters are accurate,Sc can be calculated directly fromρob,and then Sa can be obtained from ***,if the chemical reaction parameters(denoted asγ)are insufficiently accurate,bothγand Sc should be *** article proposes a"double correction iterative method"to retrieve Sc and correctγand proves that this iterative method converges.

关键词： Air pollution Anthropogenic emission source Source due to chemical reaction Source retrieval Incomplete adjoint operator Double correction iterative method

Optimal reduction of anthropogenic emissions for air pollution control and the retrieval of emission source from observed pollutants Ⅰ. Application of incomplete adjoint operator

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Science China Earth Sciences 2018年第7期61卷 951-956页

作者： Qingcun ZENG lin wu Institute of Atmospheric Physics Chinese Academy of Sciences

The ultimate solution to anthropogenic air pollution depends on an adjustment and upgrade of industrial and energy structures. Before this process can be completed, reducing the anthropogenic pollutant emissions is an effective measure. This is a problem belonging to "Natural Cybernetics", i.e., the problem of air pollution control should be solved together with the weather prediction; however, this is very complicated. Considering that heavy air pollution usually occurs in stable weather conditions and that the feedbacks between air pollutants and meteorological changes are insufficient, we propose a simplified natural cybernetics method. Here, an off-line air pollution evolution equation is first solved with data from a given anthropogenic emission inventory under the predicted weather conditions, and then, a related "incomplete adjoint problem" is solved to obtain the optimal reduction of anthropogenic emissions. Usually, such solution is sufficient for satisfying the air quality and economical/social requirements. However, a better solution can be obtained by iteration after updating the emission inventory with the reduced anthropogenic emissions. Then, this paper discusses the retrieval of the pollutant emission source with a known spatio-temporal distribution of the pollutant concentrations, and a feasible mathematical method to achieve this is proposed. The retrieval of emission source would also help control air pollution.

关键词： Air pollution Optimal control Source retrieval Incomplete adjoint operator

Microstructure and mechanical properties of a hot-extruded Al-based composite reinforced with core–shell-structured Ti/Al3Ti

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1431-1437页

作者： Li Zhang Bao-lin wu Yu-lin Liu School of Materials Science and Engineering Shenyang Aerospace UniversityShenyang 110136China Liaoning Key Laboratory of Aviation Light Alloy and Processing Technology Shenyang Aerospace UniversityShenyang 110136China

An Al-based composite reinforced with core–shell-structured Ti/Al_3Ti was fabricated through a powder metallurgy route followed by hot extrusion and was found to exhibit promising mechanical properties. The ultimate tensile strength and elongation of the composite sintered at 620°C for 5 h and extruded at a mass ratio of 12.75:1 reached 304 MPa and 14%, respectively, and its compressive deformation reached 60%. The promising mechanical properties are due to the core–shell-structured reinforcement, which is mainly composed of Al_3Ti and Ti and is bonded strongly with the Al matrix, and to the reduced crack sensitivity of Al_3Ti. The refined grains after hot extrusion also contribute to the mechanical properties of this composite. The mechanical properties might be further improved through regulating the relative thickness of Al–Ti intermetallics and Ti metal layers by adjusting the sintering time and the subsequent extrusion process.

关键词： microstructure aluminum-based composites Ti/Al3Ti reinforcements mechanical properties

Mesopolymer modified with palladium phthalocyaninesulfonate as a versatile photocatalyst for phenol and bisphenol A degradation under visible light irradiation

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Journal of Environmental Sciences 2013年第8期25卷 1687-1695页

作者： Rong Xing lin wu Zhenghao Fei Peng wu Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection Yancheng Teachers University Yancheng 224002 China Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of Chemistry East China Normal University Shanghai 200062 China

A novel versatile photocatalyst, FDU-PdPcS, was prepared by immobilizing palladium phthalocyaninesulfonate （PdPcS） onto the FDU-15 mesopolymer via multi-step chemical modification processes involving chloromethylation of the FDU-15 mesopolymer first with chloromethyl methyl ether, a subsequent amination reaction with ethylenediamine, and finally modification with palladium phthalocyaninesulfonate via ionic interaction. The obtained FDU-PdPcS photocatalyst was characterized by the X-ray diffraction （XRD）, UV-Vis spectrosopy and inductively coupled plasma （ICP） techniques. This photocatalyst not only affords a high dispersion of monomeric PdPcS molecules, which may further be stabilized by the π-electron of benzene rings of FDU-15, but also provides a number of diamino groups inside the mesopores, which could be advantageous for the photodegradation of phenolic pollutants. In photodegradation studies of phenolic pollutants, the FDU-PdPcS catalyst exhibited excellent visible light photocatalytic activity and reusability. The photodegradation products of phenol and bisphenol A were investigated by the gas chromatoghraphy-mass spectrometry （GC-MS） technique. The results showed that the photodegradation products were composed of carboxylic acids and CO2. Isopropanol, sodium azide and benzoquinone were used as hydroxyl radical （OH.）, singlet oxygen （1O2） and superoxide radical （O2.-） scavengers, respectively. The results suggested that 1O2 and O2. were the prominent active species during the photodegradation process. A possible mechanism for the photodegradation of phenol was also discussed.

关键词： mesopolymer phthalocyanine photocatalysis visible light phenolic pollutants

Precipitation and soil particle size co-determine spatial distribution of biological soil crusts in the Gurbantunggut Desert, China

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Journal of Arid Land 2018年第5期10卷 701-711页

作者： wu lin ZHANG Yuanming Hubei University for Nationalities Enshi 445000 China Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

Biological soil crusts （BSCs） are bio-sedimentary associations that play crucial ecological roles in arid and semi-arid regions. In the Gurbantunggut Desert of China, more than 27% of the land surface is characterized by a predominant cover of lichen-dominated BSCs that contribute to the stability of the desert. However, little is known about the major factors that limit the spatial distribution of BSCs at a macro scale. In this study, the cover of BSCs was investigated along a precipitation gradient from the margins to the center of the Gurbantunggut Desert. Environmental variables including precipitation, soil particle size, soil pH, electrical conductivity, soil organic carbon, total salt, total nitrogen, total phosphorus and total potassium were analyzed at a macro scale to determine their association with differing assemblages of BSCs （cyanobacteria crusts, lichen crusts and moss crusts） using constrained linear ordination redundancy analysis （RDA）. A model of BSCs distribution correlated with environmental variables that dominated the first two axes of the RDA was constructed to clearly demonstrate the succession stages of BSCs. The study determined that soil particle size （represented by coarse sand content） and precipitation are the most significant drivers influencing the spatial distribution of BSCs at a macro scale in the Gurbantunggut Desert. The cover of lichen and moss crusts increased with increasing precipitation, while the cover of cyanobacteria crusts decreased with increasing precipitation. The cover of lichen and moss crusts was negatively associated with coarse sand content, whereas the cover of cyanobacteria crusts was positively correlated with coarse sand content. These findings highlight the need for both the availability of soil moisture and a relatively stable of soil matrix, not only for the growth of BSCs but more importantly, for the regeneration and rehabilitation of disturbed BSC communities in arid and semi-arid lands. Thereby, this

关键词： biological soil crust distribution macro scale redundancy analysis (RDA) disturbance temperate desert

Inorganic nitrogen removal of toilet wastewater with an airlift external circulation membrane bioreactor

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Journal of Environmental Sciences 2007年第1期19卷 12-17页

作者： LI Gang wu lin-lin DONG Chun-song wu Guang-xia FAN Yao-bo Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Removal of inorganic nitrogen （inorganic-N） from toilet wastewater, using a pilot-scale airlift external circulation membrane bioreactor （AEC-MBR） was studied. The results showed that the use of AEC-MBR with limited addition of alkaline reagents and volumetric loading rates of inorganic-N of 0.19-0.40 kg inorganic-N/（m^3·d） helped achieve the desired nitrification and denitrification. Furthermore, the effects of pH and dissolved oxygen （DO） on inorganic-N removal were examined. Under the condition of MLSS at 1.56-2.35 g/L, BODs/ammonia nitrogen （NH4＋-N） at 1.0, pH at 7.0-7.5, and DO at 1.0-2.0 mg/L, the removal efficiencies of NH4^＋-N and inorganic-N were 91.5% and 70.0%, respectively, in the AEC-MBR. The cost of addition of alkaline reagent was approximately 0.5-1.5 RMB yuan/m^3, and the energy consumption was approximately 0.72 kWh/m^3 at the flux of 8 L/（m^2-h）.

关键词： inorganic nitrogen removal treatment of wastewater from toilet airlift external circulation membrane bioreaetor (AECMBR) membrane bioreactor (MBR)

Optimal reduction of anthropogenic emissions for air pollution control and the retrieval of emission source from observed pollutants II: Iterative optimization using a positive-negative discriminant

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Science China Earth Sciences 2020年第5期63卷 726-730页

作者： Qingcun ZENG lin wu Kece FEI Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

In part Ⅰ of this paper series, the application of an incomplete adjoint operator to calculate the optimal reduction of the total emissions S was suggested. This paper, part Ⅱ of the series, focuses on calculating the reduction of the anthropogenic emission source S. As aSc(the source term due to the chemical reaction in the atmosphere) is a complex function of the pollutant concentration, we propose an iterative optimization method using a positive-negative discriminant to obtain Sfrom he aS. Tconvergence of the iterations is also proven in this paper.

关键词： Air pollution Anthropogenic emission source Source due to chemical reaction Optimal control Iterative optimization Positive-negative discriminant

Neural Network Modeling and System Simulating for the Dynamic Process of Varied Gap Pulsed GTAW with Wire Filler

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Journal of Materials Science & Technology 2005年第4期21卷 515-520页

作者： Guangjun ZHANG Shanben CHEN lin wu State Key Laboratory of AWPT Harbin Institute of Technology Harbin 150001 China Institute of Welding Technology Shanghai Jiao Tong University Shanghai 200030 China

As the base of the research work on the weld shape control during pulsed gas tungsten arc welding （GTAW） with wire filler, this paper addressed the modeling of the dynamic welding process. Topside length Lt, maximum width Wt and half-length ratio Rh1 were selected to depict topside weld pool shape, and were measured on-line by vision sensing. A dynamic neural network model was constructed to predict the usually unmeasured backside width and topside height of the weld through topside shape parameters and welding parameters. The inputs of the model were the welding parameters （peak current, pulse duty ratio, welding speed, filler rate）, the joint gap, the topside pool shape parameters （Lt, Wt, and Rh1）, and their history values at two former pulse, a total of 24 numbers. The validating experiment results proved that the artificial neural network （ANN） model had high precision and could be used in process control. At last, with the developed dynamic model, steady and dynamic behavior was analyzed by simulation experiments, which discovered the variation rules of weld pool shape parameters under different welding parameters, and further knew well the characteristic of the welding process.

关键词： Modeling Neural network Dynamic welding process Pulsed GTAW

Genetic architecture, epigenetic influence and environment exposure in the pathogenesis of Autism

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Science China(Life Sciences) 2015年第10期58卷 958-967页

作者： YU Li wu YiMing wu Bai-lin Children's Hospital of Fudan University Institutes of Biomedical Science Shanghai Medical College of Fudan University Claritas Genomics Boston Children's Hospital Harvard Medical School

Autism spectrum disorder(ASD) is a spectral neurodevelopment disorder affecting approximately 1% of the population. ASD is characterized by impairments in reciprocal social interaction, communication deficits and restricted patterns of behavior. Multiple factors, including genetic/genomic, epigenetic/epigenomic and environmental, are thought to be necessary for autism development. Recent reviews have provided further insight into the genetic/genomic basis of ASD. It has long been suspected that epigenetic mechanisms, including DNA methylation, chromatin structures and long non-coding RNAs may play important roles in the pathology of ASD. In addition to genetic/genomic alterations and epigenetic/epigenomic influences, environmental exposures have been widely accepted as an important role in autism etiology, among which immune dysregulation and gastrointestinal microbiota are two prominent ones.

关键词： autism spectrum disorder genetic architecture genomie disorder gene mutation copy number variants single nucleotide variants genetic pathways epigenetic influence DNA methylation chromatin remodeling long non-coding RNAs environment exposure immune dysregulation gastrointestinal microbiota