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Morphology,composition,and sources of individual aerosol particles at a regional background site of the YRD,China

Journal of Environmental Sciences 2019年第3期31卷 354-362页

作者： Liang Xu A.P.Lingaswamy Yinxiao Zhang Lei Liu Yuanyuan Wang Jian Zhang Qianli Ma Weijun Li Environment Research Institute Shandong University Santhiram Engineering College Lin'an Air Background Station (LABS) Department of Atmospheric Sciences School of Earth Sciences Zhejiang University

Aerosol samples were collected at Lin'an, a background site of Yangtze River Delta(YRD).Morphology, size, composition, and mixing state of individual aerosol particles were characterized by transmission electron microscopy(TEM) coupled with energy dispersive X-ray spectroscopy(EDS), and the soluble ions of PM_(1.0) were studied by aerosol mass spectrometer(AMS). The daily average AMS mass concentrations of sulfate, nitrate, and ammonium were about 5.8, 8.6, and 5.6 μg/m^3, respectively. individual aerosol particles were classified into seven types: S-rich, K-rich, organic matter(OM), soot, fly ash, metal, and mineral. S-rich particles were dominant in all size bins, and 51%(by number) of S-rich particles were internally mixed with other particles. The fraction of organic coating particles was 13.7% in morning, 25.2% in afternoon, and 11% in evening, suggesting that the strong photochemical process during afternoon produced more secondary organic aerosols(SOA) on the surface of inorganic particles. Fly ash and metal particles were abundant during the day, suggesting the influence of emissions from coal-fired power plants and steel plants. The results indicate that the intense industrial emissions in the YRD significantly transported to the background areas. PM_(2.5) concentration may be lower in background air than in urban air but complex mixing state of aerosol particles indicates that the long-range transported particles substantially influenced the background air quality.

关键词： Regional background air Transmission electron microscopy individual aerosol particles Mixing state Yangtze River Delta

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Elastic Interaction between a String of Cells and an individual Cell

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Chinese Physics Letters 2007年第5期24卷 1407-1409页

作者：吴恒安龙荣王秀喜王奉超 CAS Key Laboratory of Materials Behavior and Design Department of Mechanics and Mechanical Engineering University of Science and Technology of China Hefei 230026

The elastic interaction between a string of cells and an individual cell on an elastic substrate is investigated numerically using the force-dipole model. This interaction is found to be of short range, and the cut-off distance is about 1.4 times of the length of the cell. The energy-minimization distance is about half the cellular length. The specific relationship between the cellular reorientation and the cellular position are obtained quantitatively. A critical distance is found, and the cellular orientation has an abrupt change at this transition point.

关键词： Interaction individual energy-minimization

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Physicochemical analysis of individual atmospheric fine particles based on effective surface-enhanced Raman spectroscopy

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Journal of Environmental Sciences 2019年第1期31卷 388-395页

作者： Zhenli Sun Fengkui Duan Kebin He Jingjing Du Liu Yang Hui Li Tao Ma Shuo Yang State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Tsinghua University State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Fine particles associated with haze pollution threaten the health of more than 400 million people in China. It is therefore of great importance to thoroughly investigate and understand their composition. To determine the physicochemical properties in atmospheric fine particles at the micrometer level, we described a sensitive and feasible surface-enhanced Raman scattering(SERS) method using Ag foil as a substrate. This novel method enhanced the Raman signal intensities up to 10,000 a.u. for ν(NO_3^-) in fine *** SERS effect of Ag foil was further studied experimentally and theoretically and found to have an enhancement factor of the order of ～10~4. Size-fractionated real particle samples with aerodynamic diameters of 0.4–2.5 μm were successfully collected on a heavy haze day,allowing ready observation of morphology and identification of chemical components, such as soot, nitrates, and sulfates. These results suggest that the Ag-foil-based SERS technique can be effectively used to determine the microscopic characteristics of individual fine particles, which will help to understand haze formation mechanisms and formulate governance policies.

关键词： SERS PM2.5 individual particle Atmospheric

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Evaluation of the individual hydrogen bonding energies in N-methylacetamide chains

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Science China Chemistry 2010年第8期53卷 1754-1761页

作者： XiaoNan Jiang ChangSheng Wang School of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 China

The individual hydrogen bonding energies in N-methylacetamide chains were evaluated at the MP2/6-31+G** level including BSSE correction and at the B3LYP/6-311++G(3df,2pd) level including BSSE and van der Waals *** calculation results indicate that compared with MP2 results,B3LYP calculations without van der Waals correction underestimate the individual hydrogen bonding energies about 5.4 kJ m ol-1 for both the terminal and central hydrogen bonds,whereas B3LYP calculations with van der Waals correction produce almost the same individual hydrogen bonding energies as MP2 does for those terminal hydrogen bonds,but still underestimate the individual hydrogen bonding energies about 2.5 kJ mol-1 for the hydrogen bonds near the *** calculation results show that the individual hydrogen bonding energy becomes more negative (more attractive) as the chain becomes longer and that the hydrogen bonds close to the interior of the chain are stronger than those near the *** weakest individual hydrogen bonding energy is about-29.0 kJ m ol-1 found in the dimer,whereas with the growth of the N-methylacetamide chain the individual hydrogen bonding energy was estimated to be as large as-62.5 kJ mol-1 found in the N-methylacetamide decamer,showing that there is a significant hydrogen bond cooperative effect in N-methylacetamide *** natural bond orbital analysis indicates that a stronger hydrogen bond corresponds to a larger positive charge for the H atom and a larger negative charge for the O atom in the N-H···O=C bond,corresponds to a stronger second-order stabilization energy between the oxygen lone pair and the N-H antibonding orbital,and corresponds to more charge transfer between the hydrogen bonded donor and acceptor molecules.

关键词： N-methylacetamide chain the individual hydrogen bonding energy hydrogen bond cooperativity

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The genetic diversity, individual relatedness and possible mating system of an isolated population of the Cyprinid species Megalobrama pellgrini in upper reaches of the Changjiang (Yangtze) River, China

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Journal of Oceanology and Limnology 2019年第3期37卷 1042-1050页

作者： WANG Huanshan WANG Teng LI Wenjing LIU Huanzhang The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China

Megalobrama pellegrini is a cyprinid fish endemic to upper reaches of the Changjiang(Yangtze)River,China,which is also an important economic species in the local *** recent years,resources of this species have decreased sharply and its conservation has drawn great *** the present study,we collected 120 individuals from the Longxi River,a tributary isolated from the main channel of the Changjiang River,where *** is still relatively *** two different molecular markers,mitochondrial cytochrome b(cyt b)gene,and nuclear microsatellite(simple sequence repeat,SSR),we analyzed the genetic diversity of this isolated *** results show that sequence genetic diversity was low(Hd:0.290 and P i:0.000 77 for cyt b gene),while the SSR genetic diversity was high(Ho:0.824 4±0.147 2,He:0.823 5±0.145 1).Analysis indicated that this population had experienced a bottleneck,with inbreeding and small effective population size(around 50).Based on SSR data,relatedness analyzing revealed that the 120 samples were grouped into 10 completely independent *** was inferred that the mating system of *** was *** suggested that the low genetic diversity could be induced by the overfishing and inbreeding ***,we suggested that the urgent conservation measures should be taken to control the overfi shing and give better conditions for the fish to grow and spawn,then to restore population size.

关键词： isolated population genetic diversity individual relatedness mating system conservation

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Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science China Earth Sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2 & WU BaoXiang1 1 Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000, China 2 Department of Geology, Northwest University, Xi’an 710069, China 1. Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China2. Department of Geology Northwest University Xi’an 710069 China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in China. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -254‰ to -184‰) are lighter than those in woody plant leaf ( from -195‰ to -142‰ ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13C and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13C values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship

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Innovative deep learning artificial intelligence applications for predicting relationships between individual tree height and diameter at breast height

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Forest Ecosystems 2020年第2期7卷 141-158页

作者： ilker Ercanli Cankiri Karatekin University Faculty of Forestry18200ÇankırıTurkey

Background:Deep Learning Algorithms(DLA)have become prominent as an application of Artificial Intelligence(Al)Techniques since *** paper introduces the DLA to predict the relationships between individual tree height(ITH)and the diameter at breast height(DBH).Methods:A set of 2024 pairs of individual height and diameter at breast height measurements,originating from 150 sample plots located in stands of even aged and pure Anatolian Crimean Pine(Pinus nigra *** ***(Lamb.)Holmboe)in Konya Forest *** present study primarily investigated the capability and usability of DLA models for predicting the relationships between the ITH and the DBH sampled from some stands with different growth *** 80 different DLA models,which involve different the alternatives for the numbers of hidden layers and neuron,have been trained and compared to determine optimum and best predictive DLAs network ***:It was determined that the DLA model with 9 layers and 100 neurons has been the best predictive network model compared as those by other different DLA,Artificial Neural Network,Nonlinear Regression and Nonlinear Mixed Effect *** alternative of 100#neurons and 9#hidden layers in deep learning algorithms resulted in best predictive ITH values with root mean squared error(RMSE,0.5575),percent of the root mean squared error(RMSE%,4.9504%),Akaike information criterion(AIC,-998.9540),Bayesian information criterion(BIC,884.6591),fit index(Fl,0.9436),average absolute error(AAE,0.4077),maximum absolute error(***,2.5106),Bias(0.0057)and percent Bias(Bias%,0.0502%).In addition,these predictive results with DLAs were further validated by the Equivalence tests that showed the DLA models successfully predicted the tree height in the independent ***:This study has emphasized the capability of the DLA models,novel artificial intelligence technique,for predicting the relationships between individual tree height and the diame

关键词： Artificial intelligence Prediction Deep learning algorithms individual tree height

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Long-term monitoring of the individual self-feeding behavior of rainbow trout Oncorhynchus mykiss

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Journal of Oceanology and Limnology 2019年第1期37卷 344-349页

作者： SHI Ce GAO Xiaolong LIU Ying WANG Chunlin Key Laboratory of Applied Marine Biotechnology Ministry of Education Faculty of Life Science and Biotechnology Ningbo University Collaborative Innovation Center for Zhejiang Marine High-efficiency and Healthy Aquaculture Institute of Oceanology Chinese Academy of Sciences College of Marine Technology and Environment Dalian Ocean University

Self-feeding device is extensively used in aquaculture farms, but for salmonids the individual feeding behavior has seldom been continuously observed. In this article, the individual self-feeding behavior of 10 rainbow trout was continuously monitored with a PIT tag record for 50 days with three replicates. The?sh fell into three categories according to their feeding behavior, i.e. high triggering ?sh(trigger behavior more than 25% of the group, HT), low triggering ?sh(1%–25%, LT) and zero triggering ?sh(less than1%). The results showed that in a group of 10 individual 1–2 HT ?sh accounted for most of the self-feeding behavior(78.19%–89.14%), which was far more than they could consume. The trigger frequency of the?sh was signi?cantly correlated with the initial body weight( P 0.05). Cosinor analysis showed that the two HT ?sh in the same group had similar acrophase. Though some of the HT ?sh could be active for 50 d, there were also HT ?sh decreased triggering behavior around 40 d and the high trigger status was then replaced by other ?sh, which was ?rst discovered in salimonds. Interestingly, the growth of the group was not af fected by the alternation triggering ?sh. These results provide evidence that in the self-feeding system the HT ?sh didn't gain much advantage by their frequent self-feeding behavior, and high trigger status of the HT ?sh is not only an individual character but also driven by the demand of the group. In the self-feeding system, the critical individual should be closely monitored.

关键词： self-feeding system individual feeding behavior growth feeding rhythm

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Carbon isotopic characteristics and their genetic relationships for individual lipids in plants and sediments from a marsh sedimentary environment

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Science China Earth Sciences 2005年第8期48卷 1203-1210页

作者： DUAN Yi1, ZHANG Hui1, ZHENG Chaoyang1, WU Baoxiang1 & ZHENG Guodong2 1. Lanzhou Institute of Geology, Chinese Academy of Sciences, Lanzhou 730000, China 2. Department of Earth & Planetary System Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-85Japan 1. Lanzhou Institute of Geology Chinese Academy of Sciences 730000 Lanzhou China 2. Department of Earth & Planetary System Science Graduate School of Science Hiroshima University 739-8526 Higashi-Hiroshima Japan

The carbon isotopes of individual lipids in herbaceous plants and tree leaves in Ruoergai marsh were measured by the GC-IRMS analytical technique in order to understand the inherent relationships of carbon isotopes between sedimentary and plant lipids from typical marsh environment. The analytical results show that the carbon isotopic compositions of n-alkanes in different kinds of plants differ significantly. Mean δ 13C values of n-alkanes in her-baceous plants (?32.2‰―?36.9‰) are 3.3‰ lower than those in woody plant (?27.2‰― ?35.0‰). The carbon isotopic compositions of fatty acids in organisms (?30.3‰― ?36.2‰) are very similar to those of n-alkanes and the δ 13C values for unsaturated fatty acids are within the range of those for saturated fatty acids. The differences in δ 13C values between plant lipids are obvious and range from 2.4‰ to 7.8‰. It is observed that the carbon isotopic compositions of sedimentary lipids are closely related to those of plant lipids. The carbon isotopic compositions (?27.0‰―?36.9‰) of n-alkanes, ≥C16 fatty acids, n-alkanols, sterols and n-alkanones in the sediments are similar to those of plant lipids and the carbon isotopic compositions of short-chain sedimentary lipids are similar to those of long-chain sedimentary homologues. These indicate that the sedimentary lipids are derived from high plants. However, the δ 13C values of C14:0 and C15:0 fatty acids in the sediments are lighter than those of the same carbon number saturated homologues in plants, reflecting the genetic features partially derived from bacteria. These data provide scientific evidence for carbon isotope-applied research of individual lipids.

关键词： marsh environment, plants, sediments, individual lipids, carbon isotopic compositions, genetic relationships.

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Updating conventional soil maps by mining soil–environment relationships from individual soil polygons

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Journal of Integrative Agriculture 2019年第2期18卷 265-278页

作者： CHENG Wei ZHU A-xing QIN Cheng-zhi QI Feng State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023P.R.China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023P.R.China Department of Geography University of Wisconsin-MadisonMadison 53706USA School of Environmental and Sustainability Sciences Kean UniversityUnion 07083USA

Conventional soil maps contain valuable knowledge on soil–environment *** knowledge can be extracted for use when updating conventional soil maps with improved environmental *** methods take all polygons of the same map unit on a map as a whole to extract the soil–environment *** approach ignores the difference in the environmental conditions represented by individual soil polygons of the same map *** paper proposes a method of mining soil–environment relationships from individual soil polygons to update conventional soil *** proposed method consists of three major ***,the soil–environment relationships represented by each individual polygon on a conventional soil map are extracted in the form of frequency distribution curves for the involved environmental ***,for each environmental covariate,these frequency distribution curves from individual polygons of the same soil map unit are synthesized to form the overall soil–environment relationship for that soil map unit across the mapped *** lastly,the extracted soil–environment relationships are applied to updating the conventional soil map with new,improved environmental data by adopting a soil land inference model(SoLIM)*** study applied the proposed method to updating a conventional soil map of the Raffelson watershed in La Crosse County,Wisconsin,United *** result from the proposed method was compared with that from the previous method of taking all polygons within the same soil map unit on a map as a *** results with independent soil samples showed that the proposed method exhibited better performance and produced higher accuracy.

关键词： update conventional soil map soil–environment relationships knowledge extraction individual soil polygons

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