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Feasibility of Estimating Heavy Metal Contaminations in Floodplain Soils Using Laboratory-Based Hyperspectral Data—A Case Study Along Le’an River, china

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Geo-Spatial Information Science 2011年第1期14卷 10-16页

作者： LIU Yaolin LI Wei WU Guofeng XU Xinguo School of Resource and Environmental Science. Wuhan University 129 Luoyu Road Wuhan 430079 China Key Laboratory of Geographic Information System Ministry of Education Wuhan University 129 Luoyu Road Wuhan430079 China Sichuan Zhongshui-chengkanyuan Surveying and Mapping Engineering Company Chengdu 610072 China

It is necessary to estimate heavy metal concentrations within soils for understanding heavy metal contaminations and for keeping the sustainable developments of *** study,with the floodplain along Le'an River and its two branches in Jiangxi Province of china as a case study,aimed to explore the feasibility of estimating concentrations of heavy metal lead(Pb),copper(Cu) and zinc(Zn) within soils using laboratory-based hyperspectral *** soil samples were collected,and their hyperspectral data,soil organic matters and Pb,Cu and Zn concentrations were measured in the *** potential relations among hyperspectral data,soil organic matter and Pb,Cu and Zn concentrations were explored and further used to estimate Pb,Cu and Zn concentrations from hyperspectral data with soil organic matter as a *** results showed that the ratio of the first-order derivatives of spectral absorbance at wavelengths 624 and 564 nm could explain 52% of the variation of soil organic matter;the soil organic matter could ex-plain 59%,51% and 50% of the variation of Pb,Cu and Zn concentrations with estimated standard errors of 1.41,48.27 and 45.15 mg·kg-1;and the absolute estimation errors were 8%-56%,12%-118% and 2%-22%,and 50%,67% and 100% of them were less than 25% for Pb,Cu and Zn concentration *** concluded that the laboratory-based hyperspectral data hold potentials in esti-mating concentrations of heavy metal Pb,Cu and Zn in *** sampling points or other potential linear and non-linear regression methods should be used for improving the stabilities and accuracies of the estimation models.

关键词： soil heavy metal concentration estimation soil organic matter hyperspectral data

Hydraulic Fracturing Leads to Wolframite Deposition at Magmatic-hydrothermal transition

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 862-863页

作者： LIU Xiangchong XING Huilin ZHANG Dehui Institute of Geomechanics Chinese Academy of Geological Sciences Centre for Geoscience Computing School of Earth and Environmental Sciences The University of Queensland School of Earth Sciences and Resources China University of Geosciences (Beijing)

Objective The Nanling Range in southern china is a world-class tungsten province. It is disputed how wolframite as the main ore mineral in the tungsten deposits in this area is precipitated. Wolframite solubility is only weakly dependent on pressure （Wood and Samson, 2000）. Therefore, a pressure change cannot alter wolframite solubility. However, fluid inclusions record high-pressure fluids that trigger the initiation and propagation of vein- bearing fractures in these deposits. It is enigmatic whether a decrease in fluid pressure after hydraulic fracturing causes wolframite precipitation from hydrothermal solutions. We first demonstrate that fluid pressure drop after hydraulic fracturing could cause a significant decrease in CO2 solubility, increase pH, and facilitate wolframite precipitation at magmatic-hydrothermal transition using finite element-based numerical experiments.

关键词： CO MPa Cl

Variation of temporal and spatial patterns of NO_2 in Beijing using OMI and mobile DOAS

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Science china Chemistry 2015年第9期58卷 1367-1376页

作者： Ang Li Jie Zhang Pinhua Xie Zhaokun Hu Jin Xu Fusheng Mou Fengcheng Wu Jianguo Liu Wenqing Liu Key Laboratory of Environmental Optical and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences School of Environmental and Photoelectric Technology University of Science and Technology of China

Control policies such as "odd-and-even license plate rule" were implemented by the Chinese government to restrict traffic and suspend factory production in Beijing and neighboring cities during the Asia-Pacific Economic Cooperation summit. We use ozone monitoring instrument(OMI), mobile differential optical absorption spectroscopy(DOAS), and multi-axis differential optical absorption spectroscopy(MAX-DOAS) to measure the variation of the spatial and temporal patterns of NO2 column densities from October 24, 2014 to November 22, 2014. It is found that the NO2 column densities during the episode of control policies are significantly lower than those during other periods, and the emission flux of NO2 calculated by mobile DOAS is also lower than the results from other periods. Some daily low NO2 column densities occur with the northwest wind direction. We then compare the relationship between OMI and mobile DOAS NO2 column density observations, and the results of mobile DOAS are approximately 2.7 times larger than the OMI values. The largest discrepancy occurs in the northern part of Beijing city. In other parts, the two instruments have a better correlation coefficient(R2) of 0.61. The low NO2 column densities that occur during the episode of control policies are affected by the control policies as well as meteorological conditions.

关键词： OMI DOAS NO2 emission flux control policies

MicroRNA Dysregulation and Steroid Hormone Receptor Expression in Uterine Tissues of Rats with Endometriosis during the Implantation Window

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Chinese Medical Journal 2018年第18期131卷 2193-2204页

作者： Han Cai Xin-Xin Zhu Zhan-Fei Li Ya-Pei Zhu Jing-He Lang Department of Obstetrics and Gynecology Peking Union Medical College Hospital Beijing 100005 China

Background： Estrogen receptor （ER） and progesterone receptor （PR） are involved in endometriosis, but the involvement of microRNAs （miRNAs） is unknown. The aim of the study was to explore the correlation between miRNA and EPUPR in uterine tissues of rats with endometriosis during the implantation window. Methods： Twenty female Sprague-Dawley rats were randomized in three groups： endometriosis （n = 7）, fat tissue control （n = 6）, and normal （n = 7） groups. The female rats were mated and sacrificed on day 5 （implantation）. Uterine tissues were obtained for hematoxylin-eosin staining, immunohistochemistry, and miRNA expression. Reverse transcription polymerase chain reaction （RT-PCR） was used to validate the expression of rno-miR-29c-3p, rno-miR-34c-5p, rno-miR-14 l-5p, mo-miR-24-1-5p, and rno-miR-490-5p. Results： The 475 miRNAs were found to differentially express between the endometriosis and normal control groups, with 127 being upregulated and 348 being downregulated. Expression of five miRNAs （rno-miR-29c-3p, rno-miR-34c-5p, rno-miR-141-5p, rno-miR-24-1-5p, and rno-miR-490-5p） were validated by RT-PCR and found to be differentially expressed among the three groups. Expression of ER and PR proteins （immunohistochemistry） in the glandular epithelium and endometrial stroma was significantly different among the three groups （all P 〈 0.05）. Five miRNAs were involved in pathways probably taking part in implantation and fertility. Conclusions： The results suggested that miRNAs, ER, and PR could play important roles in the embryo implantation period of rats with endometriosis. These miRNAs might play a role in endometrial receptivity in endometriosis.

关键词： Endometriosis Estrogen Receptor Implantation MicroRNA Progesterone Receptor

Accurate location of all surface wave modes for Green's functions of a layered medium by consecutive perturbations

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Science china(Information Sciences) 2010年第11期53卷 2363-2376页

作者： SONG Zhe, ZHOU HouXing, HU Jun, LI WeiDong & HONG Wei State Key Laboratory of Millimeter Waves, School of Information Science and Engineering, Southeast University, Nanjing 210096, china State Key Laboratory of Millimeter Waves School of Information Science and Engineering Southeast University

In this paper, an efficient method is proposed to quickly and accurately locate all the surface wave modes of spectral Green’s functions of a layered medium. This method consists of two parts. In the first part, all the surface wave poles without considering the medium loss are located by a modified dichotomy on the real axis in the complex plane. In the second part, consecutive perturbations with respect to the medium loss are performed, which means that the medium loss is increased step by step from zero to the given value, and at each step, the Newton-Raphson algorithm is employed to find all the current poles, with the poles at the previous step as initial values. The residues of the surface wave poles are analytically calculated without any contour integral. The whole procedure is based on the recursively rational forms of spectral Green’s functions. As an application, all the surface wave poles and their residues obtained by the method proposed in this paper are applied in evaluation of the spatial Green’s functions by the discrete complex image method. Some numerical examples are provided to validate the correctness and efficiency of the proposed method.

关键词： Green’s function Sommerfeld integral surface wave pole perturbation discrete complex image method

Cd Toxicity and Accumulation in Rice Plants Vary with Soil Nitrogen Status and Their Genotypic Difference can be Partly Attributed to Nitrogen Uptake Capacity

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Rice science 2009年第4期16卷 283-291页

作者： Du Qin CHEN Ming-xue ZHOU Rong CHAO Zhao-yun ZHU Zhi-wei SHAO Guo-sheng WANG Guang-ming College of Agronomy and Biotechnology Southwest University Chongqing 400715 China china national Rice research Institute Hangzhou 310006 China

Two indica rice genotypes, viz. Milyang 46 and Zhenshan 97B differing in Cd accumulation and tolerance were used as materials in a hydroponic system consisting of four Cd levels （0, 0.1, 1.0 and 5.0 μmol/L） and three N levels （23.2, 116.0 and 232.0 mg/L） to study the effects of nitrogen status and nitrogen uptake capacity on Cd accumulation and tolerance in rice plants. N-efficient rice genotype, Zhenshan 97B, accumulated less Cd and showed higher Cd tolerance than N-inefficient rice genotype, Milyang 46. There was consistency between nitrogen uptake capacity and Cd tolerance in rice plants. Increase of N level in solution slightly increased Cd concentration in shoots but significantly increased in roots of both genotypes. Compared with the control at low N level, Cd tolerance in both rice genotypes could be significantly enhanced under normal N level, but no significant difference was observed between the Cd tolerances under normal N （116.0 mg/L） and high N （232.0 mg/L） conditions. The result proved that genotypic differences in Cd accumulation and toxicity could be, at least in part, attributed to N uptake capacity in rice plants.

关键词： rice (Oryza sativa) nitrogen cadmium genotypic difference nitrogen uptake capacity tolerance

Comparison of Extrapolation and Interpolation Methods for Estimating Daily Photosynthetically Active Radiation(PAR)——A Case Study of the Poyang Lake national Nature Reserve,china

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Geo-Spatial Information Science 2010年第4期13卷 235-242页

作者： WU Guofeng Jan de Leeuw Andrew K. Skidmore LIU Yaolin Herbert H. T. Prins School of Resource and Environmental Science Wuhan University 129 Luoyu Road Wuhan 430079 China Key Laboratory of Geographic Information System of the Ministry of Education Wuhan University 129 Luoyu Road Wuhan 430079 China International Livestock research Institute (ILRI) P. O. Box 30709 Nairobi 00100 Kenya Department of Natural Resources International Institute for Geo-Information Science and Earth Observation P. O. Box 6 Hengelosestraat 99 7500 AA Enschede the Netherlands Resource Ecology Group Department of Environmental Sciences Wageningen University Droevendaalsesteeg 3A 6708 PB Wageningen the Netherlands

Measurements of photosynthetically active radiation （PAR）, which are indispensable for simulating plant growth and productivity, are generally very scarce. This study aimed to compare two extrapolation and one interpolation methods for estimating daily PAR reaching the earth surface within the Poyang Lake national nature reserve, china. The daily global solar radiation records at Nanchang meteorological station and daily sunshine duration measurements at nine meteorological stations around Poyang Lake were obtained to achieve the objective. Two extrapolation methods of PARs using recorded and estimated global solar radiation at Nanchang station and three stations （Yongxiu, Xingzi and Duchang） near the nature reserve were carried out, respectively, and a spatial interpolation method combining triangulated irregular network （TIN） and inverse distance weighting （IDW） was imple- mented to estimate daily PAR. The performance evaluation of the three methods using the PARs measured at Dahuchi Conservation Station （day number of measurement = 105 days） revealed that：（1） the spatial interpolation method achieved the best PAR estima- tion （R2 - 0.89, s.c. = 0.99, F= 830.02, P 〈 0.001 ）; （2） the extrapolation method from Nanchang station obtained an unbiased result （R2 = 0.88, s.c. = 0.99, F = 745.29, P 〈 0.001）; however, （3） the extrapolation methods from Yongxiu, Xingzi and Duchang stations were not suitable for this specific site for their biased estimations. Considering the assumptions and principles supporting the extrapolation and interpolation methods, the authors conclude that the spatial interpolation method produces more reliable results than the extrapolation methods and holds the greatest potential in all tested methods, and more PAR measurements should be recorded to evaluate the seasonal, yearly and spatial stabilities of these models for their application to the whole nature reserve of Poyang Lake.

关键词： photosynthetically active radiation (PAR) extrapolation interpolation triangulated irregular network (TIN) inverse distance weighting (IDW)

A method for recovery of iron,titanium,and vanadium from vanadium-bearing titanomagnetite

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International Journal of Minerals,Metallurgy and Materials 2018年第2期25卷 131-144页

作者： Yi-min Zhang Li-na Wang De-sheng Chen Wei-jing Wang Ya-hui Liu Hong-xin Zhao Tao Qi University of Chinese Academy of Sciences Beijing 100049China national Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Beijing 100190China Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

An innovative method for recovering valuable elements from vanadium-bearing titanomagnetite is proposed. This method involves two procedures： low-temperature roasting of vanadium-bearing titanomagnetite and water leaching of roasting slag. During the roasting process, the reduction of iron oxides to metallic iron, the sodium oxidation of vanadium oxides to water-soluble sodium vanadate, and the smelting separation of metallic iron and slag were accomplished simultaneously. Optimal roasting conditions for iron/slag separation were achieved with a mixture thickness of 42.5 mm, a roasting temperature of 1200°C, a residence time of 2 h, a molar ratio of C/O of 1.7, and a sodium carbonate addition of 70 wt%, as well as with the use of anthracite as a reductant. Under the optimal conditions, 93.67% iron from the raw ore was recovered in the form of iron nugget with 95.44% iron grade. After a water leaching process, 85.61% of the vanadium from the roasting slag was leached, confirming the sodium oxidation of most of the vanadium oxides to water-soluble sodium vanadate during the roasting process. The total recoveries of iron, vanadium, and titanium were 93.67%, 72.68%, and 99.72%, respectively.

关键词： recovery vanadium titanomagnetite direct reduction sodium oxidation smelting separation water leaching

Genome-wide identification and expression analysis of the β-amylase genes strongly associated with fruit development,ripening, and abiotic stress response in two banana cultivars

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Frontiers of Agricultural Science and Engineering 2016年第4期3卷 346-356页

作者： Hongxia MIAO Peiguang SUN Yulu MIAO Juhua LIU Jianbin ZHANG Caihong JIA Jingyi WANG Zhuo WANG Zhiqiang JIN Biyu XU Key Laboratory of Tropical Crop Biotechnology Ministry of Agriculture Institute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural Sciences Key Laboratory of Genetic Improvement of Bananas Hainan Province Haikou Experimental StationChinese Academy of Tropical Agricultural Sciences Department of Agriculture Hainan University

β-amylase(BAM) is an important enzyme involved in conversion of starch to maltose in multiple biological processes in plants. However, there is currently insufficient information on the BAM gene family in the important fruit crop banana. This study identified 16 BAM genes in the banana genome. Phylogenetic analysis showed that Ma BAMs were classified into four subfamilies. Most Ma BAMs in each subfamily shared similar gene structures. Conserved motif analysis showed that all identified Ma BAM proteins had the typical glyco hydro14 domains. Comprehensive transcriptomic analysis of two banana genotypes revealed the expression patterns of Ma BAMs in different tissues, at various stages of fruit development and ripening, and in responses to abiotic stresses. Most Ma BAMs showed strong transcript accumulation changes during fruit development and late-stage ripening. Some Ma BAMs showed significant changes under cold, salt, and osmotic stresses. This finding indicated that Ma BAMs might be involved in regulating fruit development, ripening, and responses to abiotic stress. Analysis of five hormone-related and seven stressrelevant elements in the promoters of Ma BAMs further revealed that BAMs participated in various biological processes. This systemic analysis provides new insights into the transcriptional characteristics of the BAM genes in banana and may serve as a basis for further functional studies of such genes.

关键词： β-amylase banana genome-wide identification fruit development abiotic stress