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Effects of seven different companion plants on cucumber productivity, soil chemical characteristics and Pseudomonas community 被引量:4
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作者 CHANG Chun-ling FU Xue-peng +2 位作者 ZHOU Xin-gang GUO Mei-yu WU Feng-zhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2206-2214,共9页
Companion cropping can influence cucumber productivity by altering soil chemical characteristics and microbial communities. However, how these alterations affect the growth of cucumber is still unknown. In this study,... Companion cropping can influence cucumber productivity by altering soil chemical characteristics and microbial communities. However, how these alterations affect the growth of cucumber is still unknown. In this study, seven different plant species were selected as companion plants for testing their effects on cucumber productivity. The effects of different companion plants on changes in soil chemical properties such as electrical conductivity (EC) and contents of essential nutrients as well as the structure and abundance of the soil Pseudomonas community were evaluated. The results showed a higher cucumber yield in the wheat/cucumber companion system than that in the cucumber monocultured and other companion cropping systems. The lowest phosphorus (P) and potassium (K) contents in the soil were found in the cucumber monocultured system, and the highest NO3+-N and NH4*-N contents were observed in the rye/cucumber companion system. PCR-denaturing gradient gel electrophoresis (DGGE) and real-time PCR analysis showed that the trifolium/cucumber companion system increased the diversity of the soil Pseudomonas community, while the chrysanthemum/cucumber companion system increased its abundance. Interestingly, plant-soil feedback trials revealed that inoculating the soil of the wheat/cucumber companion system increased the growth of cucumber seedlings. In conclusion, the effects of different companion plants on cucumber productivity, soil chemical characteristics and the soil Pseudomonas community were different, and wheat was a more suitable companion plant for increasing cucumber productivity. In addition, the altered microbial community caused by companion cropping with wheat contributed to increased cucumber productivity. 展开更多
关键词 CUCUMBER companion plants soil chemical characteristics Pseudomonas community
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Analysis on the Chemical Characteristics of Shallow Groundwater and Causes of Formation in the Area around Poyang Lake 被引量:5
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作者 YANG Tao WANG Shi-jie 《Meteorological and Environmental Research》 CAS 2011年第9期77-80,共4页
[Objective] The study aimed at analysing the chemical characteristics of shallow groundwater and causes of formation around Poyang Lake area. [Method] The quality of shallow groundwater under seven counties or cities ... [Objective] The study aimed at analysing the chemical characteristics of shallow groundwater and causes of formation around Poyang Lake area. [Method] The quality of shallow groundwater under seven counties or cities around Poyang Lake was investigated in 2010, and compared different regions from salinity, hardness, conductivity, hydrochemistry types and so forth, so as to reveal the status quo, change characteristics and reasons of shallow groundwater. [Result] Except for pH, other water quality indicators of shallow groundwater around Poyang Lake were better, attaining Class I water quality standards. Among these regions, the salinity, hardness, conductivity, Na+, K+, Ca2+, Mg2+, Cl- and HCO-3 concentration of shallow groundwater in Nanchang city were up to the maximum values, while pH and SO2-4 concentration were the highest in Duchang County; Mg2+ concentration and pH were the lowest in Poyang County, and hardness, K+, Ca2+, SO2-4 and Cl- concentration in Yongxiu County reached the minimum values, while Na+ concentration, salinity and conductivity were the lowest in Jinxian County. In addition, the better quality of groundwater around Poyang Lake was closely related to the low level of economic development in Jiangxi Province. Meanwhile, many water quality indices in Nanchang City reached the maximum values, and even tended to Class Ⅱ water quality standards, which resulted from the high level of economic development and decisive role of human activities. [Conclusion] The research could provide references for the establishment of management strategies for regional shallow groundwater. 展开更多
关键词 Poyang Lake Shallow groundwater chemical characteristics China
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Electrokinetic chemical characteristics of humic and dannic acids effecting on the natural water and its coagulation 被引量:1
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作者 Qu Jiuhui Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第1期71-79,共9页
Taking streaming current(SC)as the electrokinetic parameter,this paper demon- strated the electrokinetic chemical characteristics of humic and dannic acids(HA and DA)in sus- pensions including turbid water,coagulated ... Taking streaming current(SC)as the electrokinetic parameter,this paper demon- strated the electrokinetic chemical characteristics of humic and dannic acids(HA and DA)in sus- pensions including turbid water,coagulated water and HA or DA contained water.Accordingly, the studies were carried out for determining the relationship between streaming current and zeta po- tential ζ(expressed by eleetrophoretie mobility EM)in above water conditions.In addition,the mechanisms of HA effecting on streaming current within or after coagulant addition and the elec- trokinetic detection principles for HA or DA were also investigated on experiments and theoretical analysis.The results indicated that the change of SC like ζ presented meaningful information con- cerning the degree for destabilization of a particulate suspension,and HA or DA in water could re- markably decrease the effect of inorganic coagulant upon streaming current,which is in accordance with their influence on coagulation. 展开更多
关键词 electrokinetic chemical characteristics humic acid dannic acid natural water.
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Anatomical and Chemical Characteristics of a Rolling Leaf Mutant of Rice and Its Ecophysiological Properties 被引量:1
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作者 BAI Lei DUAN Zhuang-qin +3 位作者 WANG Jun-min AN Li-zhe ZHAO Zhi-guang CHEN Kun-ming 《Rice science》 SCIE 2008年第3期201-208,共8页
The anatomical and chemical characteristics of a rolling leaf mutant (rlm) of rice (Oryza sativa L.) and its ecophysiological properties in photosynthesis and apoplastic transport were investigated. Compared with ... The anatomical and chemical characteristics of a rolling leaf mutant (rlm) of rice (Oryza sativa L.) and its ecophysiological properties in photosynthesis and apoplastic transport were investigated. Compared with the wild type (WT), the areas of whole vascular bundles and xylem as well as the ratios of xylem area/whole vascular bundles area and xylem area/phloem area were higher in rim, whereas the area and the width of foliar bulliform cell were lower. The Fourier transform infrared (FTIR) microspectroscopy spectra of foliar cell walls differed greatly between rim and WT. The rim exhibited lower protein and polysaccharide contents of foliar cell walls. An obvious reduction of pectin content was also found in rim by biochemical measurements. Moreover, the rate of photosynthesis was depressed while the conductance of stoma and the intercellular CO2 concentration were enhanced in rim. The PTS fluorescence, which represents the ability of apoplastic transport, was 11% higher in rim than in WT. These results suggest that the changes in anatomical and chemical characteristics of foliar vascular bundles, such as the reduction of proteins, pectins, and other polysaccharides of foliar cell walls, participate in the leaf rolling mutation, and consequently lead to the reduced photosynthetic dynamics and apoplastic transport ability in the mutant. 展开更多
关键词 RICE rolling leaf mutant anatomical characteristics chemical characteristics apoplastic transport ecophysiological property Fourier transform infrared microspectroscopy
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Mineral Chemical Characteristics of Gabbro-diorite for Shulouqiu Uranium Deposit in Northern Guangdong, China: Constraint on the Magmatic Source
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作者 ZHONG Fujun PAN Jiayong +2 位作者 LIU Guoqi LIU Wenquan QI Jiaming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期109-110,共2页
1 Introduction The uranium deposits related with Indosinian and Yanshanian granite have provided the abundant resource of uranium during the past several decades in China.The deposits are mainly distributing in the Gu... 1 Introduction The uranium deposits related with Indosinian and Yanshanian granite have provided the abundant resource of uranium during the past several decades in China.The deposits are mainly distributing in the Guidong granite 展开更多
关键词 China Constraint on the Magmatic Source Mineral chemical characteristics of Gabbro-diorite for Shulouqiu Uranium Deposit in Northern Guangdong
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Studies on Dynamic of Physical and Chemical Characteristics of Water in GaoBaZhou Reservoir after Filter-feeding Fish's Multiplication and Stocking
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作者 CAI Yu LIU Zhi-guo +5 位作者 CAI Yan-zhi WAN Song-tong XIA Jian-jun LI Xian-cai LEI Xiao-zhong WANG Liang 《Animal Husbandry and Feed Science》 CAS 2012年第5期231-235,共5页
[ Objective] The aim was to provide scientific basis for purifying water quality, ecological restoration and fishery breeding of GaoBaZhou reservoir multiplication and stocking. [ Method] Monitoring of normal water ph... [ Objective] The aim was to provide scientific basis for purifying water quality, ecological restoration and fishery breeding of GaoBaZhou reservoir multiplication and stocking. [ Method] Monitoring of normal water physical, chemical characteristics and different number of data of GaoBaZhou reservoir was conducted in 2010 and 2011 after different amount of filter-feeding fishes stocking in this reservoir. [ Result] The water physical and chemical factors TN, NO2, NO3-N-N, TP and COD, Chl. a in 2011 were significantly less than 2010, 2011 month average 1.389 mg/L, 0.039 6 rng/L, 1.211 7 mg/L, 0.137 3 mg/L, 16.191 mg/L, 10.226 8 mg/m3, 2010 month average 1.659 mg/L, 0.066 2 mg/L, 1.472 9 mg/L, 0.099 9 rag/L, 18.314 8 mg/L, 14.917 8 mg/L. The calculation results of TSIM showed that 2011 reservoir eutrophication TSIM were less than 2010, up to 53.78 and 57.36. E Coaclusion: The whole reservoir area revealed mild eutrophication (the TSIM 〉 53), and it suggested that the filterfeeding fishes amount could be increased in the reservoir. 展开更多
关键词 GaoBaZhou reservoir Multiplication and stocking Physical and chemical characteristics Purification effect
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Chemical Characteristics of Cr-spinel of Chromites in Kuda Ophiolite of Western Kunlun and Its Geological Implications
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作者 QIAO Gengbiao WANG Ping ZHAO Xiaojian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期192-,共1页
The Kuda ophiolite belongs to the early Paleozoic ophiolite belt in Western Kunlun Mountains and is composed of metamorphic peridotites,cumulate peridotites,mafic volcanic rocks and quartzites(Li et al.,
关键词 chemical characteristics of Cr-spinel of Chromites in Kuda Ophiolite of Western Kunlun and Its Geological Implications Cr
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Study on Chemical Characteristics of Rainfall in Tobacco-Growing Regions of Chenzhou, Hunan Province
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作者 Xiangzhen Kong Yansong Xiao +7 位作者 Qinyi Zhi Yahua Liao Bin He Hong Jian Juan Li Zhihui Cao Sijun Li Decheng Li 《Agricultural Sciences》 CAS 2022年第7期821-840,共20页
In order to clarify the chemical properties of rainfall in typical tobacco areas in Chenzhou City, Hunan Province, and analyze its potential for soil and flue-cured tobacco planting, rainfall samples in 2020 were coll... In order to clarify the chemical properties of rainfall in typical tobacco areas in Chenzhou City, Hunan Province, and analyze its potential for soil and flue-cured tobacco planting, rainfall samples in 2020 were collected by rainfall instruments in Fangyuan Town and Aoquan Town of Guiyang County, and the chemical properties that are closely related to the quality of flue-cured tobacco were determined, such as pH, EC, total nitrogen (TN), nitrate nitrogen (), ammonium nitrogen () and ion concentrations (K<sup>+</sup>, Na<sup>+</sup>, Ca<sup>2+</sup>, Mg<sup>2+</sup>, , Al<sup>3+</sup>, , Cl<sup>&#8722;</sup>,). The results show that the pH values of rainfall samples at Fangyuan and Aoquan monitoring sites are in the range of 4.92 - 6.17 and 4.93 - 5.69 respectively, with an average of 5.27 and 5.27 respectively. The acid rain characteristic is very obvious, which is mainly dominated by . The variation of rainfall EC has seasonal characteristics. EC is low from January to September, in the range of 6.09 - 56.72 and 11.83 - 30.93 μS/cm respectively, besides, it is high from October to December, in the range of 102.63 - 174.60 and 25.05 - 86.37 μS/cm respectively. The annual deposition of TN was 22.19 and 20.76 kg/hm<sup>2</sup>/yr respectively, which were higher than that in the western regions with less human disturbance, but lower than or equal to that in the developed agricultural regions in eastern China. The proportion of in the annual deposition of TN was higher than that of at two monitoring sites, with an average of 56.51% and 38.86% respectively. Ammonia volatilization from agricultural activities contributed more to rainfall nitrogen content. The ratios of ammonium nitrogen to nitrate nitrogen deposition at two monitoring points were 1.84, 1.81, 1.86 and 1.34, 1.46, and 1.29 during the whole year, summer and autumn, winter and spring respectively. The ratio is higher in summer and autumn than in winter and spring. The weighted average equivalent concentrations of the main ions at two monitoring sites were 238.88 μeq/L and 211.21 μeq/L respectively, and the orders of the ion concentrations were slightly different. Both the concentrations of and are higher, while Mg<sup>2+</sup>, and Al<sup>3+</sup> are lower. , and are mainly from human activities with a contribution rate between 91.90% and 99.35%. Ca<sup>2+</sup> mainly comes from soil and ground dust, besides, Cl<sup>&#8722;</sup> and Mg<sup>2+</sup> mainly come from marine sources and K<sup>+</sup> mainly comes from terrestrial sources. In general, the acidic rainfall and higher concentration are beneficial to reducing the high pH value of soil in Aoquan tobacco area and improving the quality of flue-cured tobacco. Higher concentrations of and in rainfall are not conducive to the improvement of flue-cured tobacco quality, because of the high content of soil available sulfur in Chenzhou tobacco area and the characteristics of flue-cured tobacco’s preference for ammonium. 展开更多
关键词 RAINFALL chemical characteristics PH Nitrogen Form Ion Composition Tobacco-Growing Region Chenzhou
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Physicochemical Characteristics of Calamondin(Citrus microcarpa)from Hainan 被引量:1
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作者 Yi ZOU Hongjian ZHANG Lianhe ZHENG 《Asian Agricultural Research》 2020年第12期58-62,共5页
Some physicochemical characteristics of calamondin(Citrus microcarpa)from Hainan were determined in this study.The mean length,width,and thickness of calamondin were(2.763±0.262),(2.721±0.189),and(2.684±... Some physicochemical characteristics of calamondin(Citrus microcarpa)from Hainan were determined in this study.The mean length,width,and thickness of calamondin were(2.763±0.262),(2.721±0.189),and(2.684±0.201)cm,respectively.The average values for geometric mean diameter,sphericity,fruit shape index,mass,surface area,volume,true density,bulk density and porosity were(2.721±0.196)cm,(98.79±5.149)%,(101.64±7.609)%,(11.18±2.149)g,(23.36±3.362)cm2,(11.16±2.115)cm3,(1.00±0.060)g/cm3,0.44 g/cm3,and(56.40±0.027)%,respectively.The mean edible part,juice rate,and soluble solids were(85.77±3.53),(48.36±4.20),and(7.86±0.09)%,respectively.The total flavonoids,pectin,limonin,reducing sugar and volatile oil contents of the peel were 1.00,7.14,0.51,5.98,and 4.25%,respectively.The total flavonoids,pectin,limonin and reducing sugar contents of the pulp were 0.02,5.04,0.03 and 4.56%,respectively.The total flavonoids,total acid,reducing sugar and vitamin E contents of the juice were 0.11,6.74,0.37%,and 1.68 mg/kg,respectively,while the content of vitamins A,B1,B2,B3,B6,and D in the juice was very low.The seeds had limonin,reducing sugar and oil contents of 0.46,1.39,and 30.46%,respectively.The vitamin B2,B3,B6 and E contents of the fruit residue were 44.83,19.31,17.55,and 15.72 mg/kg,respectively.The amino acid profile of the residue included aspartic acid,glutamate,cystine,serine,glycine,histidine,arginine,threonine,alanine,proline,tyrosine,valine,methionine,isoleucine,leucine,phenylalanine and lysine,with respective contents of 4.42,1.81,2.10,0.78,0.59,0.20,0.72,0.160.67,3.650.50,0.67,0.59,1.00,0.76,0.57 and 0.91 g/kg. 展开更多
关键词 Hainan calamondin Physical characteristic chemical characteristic Nutrient content
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Effects of Varieties and Cooking Methods on Physical and Chemical Characteristics of Cooked Rice 被引量:1
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作者 Merynda Indriyani SYAFUTRI Filli PRATAMA +1 位作者 Friska SYAIFUL Achmad FAIZAL 《Rice science》 SCIE CSCD 2016年第5期282-286,共5页
To analyze the effect of different lowland rice varieties and different cooking methods on physical and chemical characteristics of cooked rice. A factorial randomized block design with two factors was used and each c... To analyze the effect of different lowland rice varieties and different cooking methods on physical and chemical characteristics of cooked rice. A factorial randomized block design with two factors was used and each combination of the factors was repeated three times. The first factor was rice variety(Ciherang and Ciliwung) and the second factor was the cooking method(stovetop, boiling and steaming, and rice cooker). Results showed that Ciherang and Ciliwung varieties were classified into slender grain rice type with yellowred color. The amylose content of Ciherang was classified as moderate, while the amylose content of Ciliwung classified as low. The most abundant amino acid contained in Ciherang and Ciliwung varieties was glutamic acid. Statistical analysis showed that cooking method had significant effects on texture, lightness, chroma, hue and moisture content of cooked rice. Rice cooked with liwet method had the lowest texture value, lowest lightness value, highest chroma value, and highest moisture content. 展开更多
关键词 physical and chemical characteristic cooking method rice variety amino acid
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The Hydrochemical Characteristics of a Stressed Sand-Gravel Aquifer: Kazan Plain, Ankara, Turkey
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作者 Ahmet Apaydin Beril Salman Akin Eda Kaya 《Journal of Environmental Protection》 2021年第11期961-982,共22页
Over-exploitation and sand-gravel mining affect groundwater resources in terms of both quantity and quality. Groundwater level and well yields in and around the sand-gravel pits significantly decrease. Sand-gravel min... Over-exploitation and sand-gravel mining affect groundwater resources in terms of both quantity and quality. Groundwater level and well yields in and around the sand-gravel pits significantly decrease. Sand-gravel mining also changes the turbidity levels and temperature of groundwater. Reduction and destruction of valuable aquifers are significant issues. In this case, the natural state of the aquifer disappears. The Kazan Plain in central Turkey is a dramatic example of these kinds of results. The productive sand-gravel aquifer in the Kazan plain has been substantially damaged due to intensive sand-gravel mining since the 1980s. Additionally, over-exploitation has caused notable declines in groundwater levels, particularly in the 2000s. This study focuses on the hydrogeochemical situation of the Kazan Plain alluvium aquifer after intensive sand-gravel mining and over-exploitation. Groundwater samples were collected seasonally in 2015, five years after the over-exploitation and heavy sand-gravel mining. The decline reached 20 m (about half of the saturated thickness of the sand-gravel aquifer) in the region where the intensive groundwater abstraction lasted until 2010. Some quarries continued to operate until 2010, but after that mining activity continued only at a minimum level. Today, groundwater quality has been significantly degraded due to the over-exploitation of sand-gravel mining and also the cessation of recharge from fresh river water. 展开更多
关键词 chemical Characteristic Sand-Gravel Mining Groundwater Over-Exploitation
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Some of the Chemical and Physical Characteristics of the Graff River in Kut City, Iraq
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作者 Salih Mahdi Ali Imad Kazem Ali 《Open Journal of Modern Hydrology》 CAS 2024年第1期56-67,共12页
Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period fro... Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period from October/2018 to March/2019, Seven variables of river water have been analyzed: temperature PH, electrical conductivity, TDS, turbidity, alkaline, and chloride. The results showed that most of the chemical and physical water properties of the river were in normal proportions and did not rise, except for the turbidity, which was at a very high level, and that the pH values were close to the basal side. The results of the statistical analysis revealed positive significant relationships between the pH and (chloride and TDS). On the other hand, between electrical conductivity and both previous variables as well. And a negative significant connection between temperature and alkaline. 展开更多
关键词 Graff River Kut City Iraq chemical characteristics Physical characteristics
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Chemical characteristics of size-resolved aerosols in winter in Beijing 被引量:9
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作者 Kang Sun Yu Qu +16 位作者 Qiong Wu Tingting Han Jianwei Gu Jingjing Zhao Yele Sun Qi Jiang Ziqi Gao Min Hu Yuanhang Zhang Keding Lu Stephan Nordmann Yafang Cheng Li Hou Hui Ge Masami Furuuchi Mitsuhiko Hata Xingang Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第8期1641-1650,共10页
Size-resolved aerosols were continuously collected by a Nano Sampler for 13 days at an urban site in Beijing during winter 2012 to measure the chemical composition of ambient aerosol particles. Data collected by the N... Size-resolved aerosols were continuously collected by a Nano Sampler for 13 days at an urban site in Beijing during winter 2012 to measure the chemical composition of ambient aerosol particles. Data collected by the Nano Sampler and an ACSM(Aerodyne Aerosol Chemical Speciation Monitor) were compared. Between the data sets,similar trends and strong correlations were observed,demonstrating the validity of the Nano Sampler. PM10 and PM2.5concentrations during the measurement were 150.5 ± 96.0 μg/m3(mean ± standard variation)and 106.9 ± 71.6 μg/m3,respectively. The PM2.5/PM10 ratio was 0.70 ± 0.10,indicating that PM2.5dominated PM10. The aerosol size distributions showed that three size bins of 0.5–1,1–2.5 and 2.5–10 μm contributed 21.8%,23.3% and 26.0% to the total mass concentration(TMC),respectively. OM(organic matter) and SIA(secondary ionic aerosol,mainly SO42-,NO3-and NH4+) were major components of PM2.5. Secondary compounds(SIA and secondary organic carbon) accounted for half of TMC(about 49.8%) in PM2.5,and suggested that secondary aerosols significantly contributed to the serious particulate matter pollution observed in winter. Coal burning,biomass combustion,vehicle emissions and SIA were found to be the main sources of PM2.5. Mass concentrations of water-soluble ions and undetected materials,as well as their fractions in TMC,strikingly increased with deteriorating particle pollution conditions,while OM and EC(elemental carbon) exhibited different variations,with mass concentrations slightly increasing but fractions in TMC decreasing. 展开更多
关键词 AEROSOL Size distribution chemical characteristics BEIJING
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Chemical characteristics of precipitation at Nanping Mangdang Mountain in eastern China during spring 被引量:8
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作者 Yanli Cheng Ying Liu +4 位作者 Mingqun Huo Qian Sun Huixiang Wang Zhongming Chen Yuhua Bai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第8期1350-1358,共9页
To study the characteristics of precipitation in eastern China, an automatic sampler was used to collect rainwater samples from 19 precipitation events at Mangdang Mountain, Nanping City, Fujiang Province, in the spri... To study the characteristics of precipitation in eastern China, an automatic sampler was used to collect rainwater samples from 19 precipitation events at Mangdang Mountain, Nanping City, Fujiang Province, in the spring of 2009. We used ion chromatography to analyze the ionic components and concentrations, and inductively coupled plasma mass spectrometry (ICP-MS) to analyze dement compositions and contents. The results demonstrated remarkable acidic characteristics: in more than 80% of precipitation events the pH was less than 5.6, with an average of 4.81. Mass concentration results showed SO42- was the main anionic component (36.2% of the total anion mass), while N/-/4+ was the main cationic component (47.7% of the total cation mass) and main ion for acidity neutralization in the rainwater. Organic acid content accounted for 30.9% of total anion mass. The main trace metals were Ca, K, and Na. The S042-/N03- ratio was 1.4, indicating that precipitation in this region was influenced by complex air pollution - the product of individual coal-burning combined with vehicle exhaust pollution. Correlation analysis of the chemical composition of the precipitation indicated that acidity in this region was determined by a combination of all acidic and neutralization ions rather than any single ion component. The results also showed that Na+ and C1- contributions were mainly by seawater; Mg2+ by seawater and crustal materials; the NH4+, K~, Ca2+, NO3- and SO42- by anthropogenic sources; the trace metals were from the Earth's crust; and organic acids were potentially from combustion of biomass. 展开更多
关键词 chemical characteristics enrichment factor Mangdang Mountain PRECIPITATION
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Chemical characteristics and source apportionment of atmospheric particles during heating period in Harbin, China 被引量:6
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作者 Likun Huang Guangzhi Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第12期2475-2483,共9页
Atmospheric particles(total suspended particles(TSPs); particulate matter(PM) with particle size below 10 μm, PM10; particulate matter with particle size below 2.5 μm, PM2.5)were collected and analyzed during ... Atmospheric particles(total suspended particles(TSPs); particulate matter(PM) with particle size below 10 μm, PM10; particulate matter with particle size below 2.5 μm, PM2.5)were collected and analyzed during heating and non-heating periods in Harbin. The sources of PM10 and PM2.5were identified by the chemical mass balance(CMB) receptor model.Results indicated that PM2.5/TSP was the most prevalent and PM2.5was the main component of PM210, while the presence of PM10–100was relatively weak. SO-4and NO-3concentrations were more significant than other ions during the heating period. As compared with the non-heating period, Mn, Ni, Pb, S, Si, Ti, Zn, As, Ba, Cd, Cr, Fe and K were relatively higher during the heating period. In particular, Mn, Ni, S, Si, Ti, Zn and As in PM2.5were obviously higher during the heating period. Organic carbon(OC) in the heating period was 2–5 times higher than in the non-heating period. Elemental carbon(EC) did not change much. OC/EC ratios were 8–11 during the heating period, which was much higher than in other Chinese cities(OC/EC: 4–6). Results from the CMB indicated that 11 pollution sources were identified, of which traffic, coal combustion, secondary sulfate, secondary nitrate, and secondary organic carbon made the greatest contribution. Before the heating period, dust and petrochemical industry made a larger contribution. In the heating period, coal combustion and secondary sulfate were higher. After the heating period, dust and petrochemical industry were higher. Some hazardous components in PM2.5were higher than in PM10, because PM2.5has a higher ability to absorb toxic substances. Thus PM2.5pollution is more significant regarding human health effects in the heating period. 展开更多
关键词 Atmospheric particles chemical characteristics Heating period chemical mass balance
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Chemical and physical characteristics of quartz from gold deposits in the North China platform: relationship to gold mineralization 被引量:1
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作者 Jianzhao Yin Yang Liu Hongyun Shi 《Acta Geochimica》 EI CAS CSCD 2021年第6期998-1022,共25页
This paper seeks to identify macroscopic metallogenic mechanisms of various mineral deposits by studying microscopic typomorphic characteristics of typical minerals associated with the deposits and to reveal the mecha... This paper seeks to identify macroscopic metallogenic mechanisms of various mineral deposits by studying microscopic typomorphic characteristics of typical minerals associated with the deposits and to reveal the mechanism of lattice gold in detail by studying both physical and chemical characteristics of quartz from representative gold deposits in the North China Platform.As part of their extensive research,the authors examine the relationship between trace elements with wall rock,the ore-forming media,and gold immigration of various types of gold deposits,including their salinity,type,temperature.These are key factors to revealing the mineralization mechanism,and indicators for mineral prospecting,exploration,mining,and metallurgical technology.In order to address the questions posed,the following methods were used:field investigations of geology and sampling of the representative gold deposits,physical study and chemical analysis of quartz including,but not limited to,fluid inclusions as well as their compositions and trace elements in quartz,the unit cell parameters,electron paramagnetic resonance spectrum(EPR),and infrared spectroscopic analysis(ISA).As a result of this study,the authors observe the following key findings:unit cell parameters of quartz vary with their contents of foreign elements including gold,paragenetic stage,wall rock type,and other factors;the higher the forming temperature and the lower the gold content in quartz,the smaller the unit cell parameters,and vice versa.Additionally,the EPR absorption lines resulted from the O–Al defect center.The density of these types of hole centers increases and the EPR signal strengthens when the temperature decreases.Based on the findings,the authors conclude that lattice gold exists in quartz.Gold,in the form of Au^(+)and/or Au^(3+),entering quartz and producing an electron–hole center,namely,the O-Au hole center,makes the center produce spin resonance absorption and results in the EPR absorption peak#I.Both unit cell parameters and EPR of quartz can potentially be used in mineral prospecting,relative ore-forming temperature determination,and grade control during mining. 展开更多
关键词 Physical and chemical characteristics QUARTZ Gold mineralization Unit cell parameter Electron paramagnetic resonance spectrum Infrared spectrum
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Observational study of the physical and chemical characteristics of the winter radiation fog in the tropical rainforest in Xishuangbanna, China 被引量:1
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作者 Yuan WANG Shengjie NIU +8 位作者 Chunsong LU Jingjing LV Jing ZHANG Hongwei ZHANG Sirui ZHANG Naifu SHAO Wei SUN Yuchen JIN Qinghai SONG 《Science China Earth Sciences》 SCIE EI CSCD 2021年第11期1982-1995,共14页
We conducted a three-month field experiment focusing on the physical and chemical characteristics of fog in a tropical rainforest in Xishuangbanna,Southwest China,in the winter of 2019.In general,the fog would form at... We conducted a three-month field experiment focusing on the physical and chemical characteristics of fog in a tropical rainforest in Xishuangbanna,Southwest China,in the winter of 2019.In general,the fog would form at midnight and persist because of the increased long-wave radiative cooling combined with the high relative humidity,gentle breeze,and a relatively low aerosol number concentration in the forest;the fog would dissipate before noon due to the increasing turbulence near the surface.This diurnal cycle is typical for radiation fog.The microphysical fog properties included a relatively low number concentration of the fog droplet,large droplet size,high liquid water content,narrow droplet number-size distribution,and high supersaturation.The chemical properties showed that the fog water was slightly alkaline with low electrical conductivity,whereas the highest proportions of anions and cations therein were Cl^(−)and Ca^(2+),respectively;the chemical components were enriched in small fog droplets.In addition,we indirectly calculated the fog supersaturation according to theκ-Köhler theory.We found that condensation broadens the droplet number-size distribution at relatively low supersaturation,which is positively correlated with the fog-droplet number concentration and negatively correlated with the droplet mean-volume diameter;this affects the key microphysical processes of fog. 展开更多
关键词 Radiation fog Formation and disappearance mechanisms Physical and chemical characteristics SUPERSATURATION Tropical rainforest
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Effects of Microbial Fertilizer on Growth Characteristics of Facility Tomato and Chemical Properties of Acidic soil 被引量:1
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作者 peiping zhang zhidian wang yao sun 《Agricultural Biotechnology》 CAS 2018年第2期55-57,70,共4页
[Objectives] This study was conducted to discuss the possibility of applying microbial fertilizer to production of facility tomato,so as to determine rational application rate for facility tomato. [Methods]A field exp... [Objectives] This study was conducted to discuss the possibility of applying microbial fertilizer to production of facility tomato,so as to determine rational application rate for facility tomato. [Methods]A field experiment was carried out to investigate the effects of the application of microbial fertilizer onto acidic soil on yield,quality and soil chemical properties of facility tomato. [Results] Yield of facility tomato was improved after the application of microbial fertilizer.Treatment ABA-2 showed the highest yield,which was higher than the CK by 7. 98%. On the basis of conventional fertilization,the combined application with microbial fertilizer could promote growth and development of tomato,and could significantly improve fruit weight,and Vc,soluble solid and lycopene contents. Furthermore,the microbial fertilizer could remarkably improve soil p H,alkali-hydrolyzale nitrogen,available phosphorus and rapidly available potassium contents.[Conclusions]The application of microbial fertilizer at 80 kg/667 m;has better effects on tomato growth and development and soil status. 展开更多
关键词 Microbial fertilizer Facility tomato Growth characteristics Soil chemical propertiesHome
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Distribution and Formation Causes of PM_(2.5) and O_(3) Double High Pollution Events in China during 2013–20
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作者 Zhixuan TONG Yingying YAN +6 位作者 Shaofei KONG Jintai LIN Nan CHEN Bo ZHU Jing MA Tianliang ZHAO Shihua QI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1235-1250,I0004-I0021,共34页
Fine particulate matter(PM_(2.5))and ozone(O_(3))double high pollution(DHP)events have occurred frequently over China in recent years,but their causes are not completely clear.In this study,the spatiotemporal distribu... Fine particulate matter(PM_(2.5))and ozone(O_(3))double high pollution(DHP)events have occurred frequently over China in recent years,but their causes are not completely clear.In this study,the spatiotemporal distribution of DHP events in China during 2013–20 is analyzed.The synoptic types affecting DHP events are identified with the Lamb–Jenkinson circulation classification method.The meteorological and chemical causes of DHP events controlled by the main synoptic types are further investigated.Results show that DHP events(1655 in total for China during 2013–20)mainly occur over the North China Plain,Yangtze River Delta,Pearl River Delta,Sichuan Basin,and Central China.The occurrence frequency increases by 5.1%during 2013–15,and then decreases by 56.1%during 2015–20.The main circulation types of DHP events are“cyclone”and“anticyclone”,accounting for over 40%of all DHP events over five main polluted regions in China,followed by southerly or easterly flat airflow types,like“southeast”,“southwest”,and“east”.Compared with non-DHP events,DHP events are characterized by static or weak wind,high temperature(20.9℃ versus 23.1℃)and low humidity(70.0%versus 64.9%).The diurnal cycles of meteorological conditions cause PM_(2.5)(0300–1200 LST,Local Standard Time=UTC+8 hours)and O_(3)(1500–2100 LST)to exceed the national standards at different periods of the DHP day.Three pollutant conversion indices further indicate the rapid secondary conversions during DHP events,and thus the concentrations of NO_(2),SO_(2) and volatile organic compounds decrease by 13.1%,4.7%and 4.4%,respectively.The results of this study can be informative for future decisions on the management of DHP events. 展开更多
关键词 double high pollution events PM_(2.5) OZONE spatiotemporal distribution meteorological causes chemical composition characteristics
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Study of aquatic chemical characteristic in some bays along the coastal region of Zhejiang Province 被引量:2
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作者 Wang Yuheng,Dong Henglin and Jiang Guochang The Second Institute of Oceanography,State Oceanic Administration ,Hangzhou,China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第4期547-554,共8页
In this paper,the aquatic chemical characteristics in the Hangzhou Bay,Xiangshan Bay and Leqing Bay along the coastal region of Zhejiang Province are discussed . Results show that the seasonal variations of chemical e... In this paper,the aquatic chemical characteristics in the Hangzhou Bay,Xiangshan Bay and Leqing Bay along the coastal region of Zhejiang Province are discussed . Results show that the seasonal variations of chemical elements are obvious. The distribution of silicate in Hangzhou Bay and contents of dissolved oxygen and nutrient in the Xiangshan Bay are found to be unusual in winter. Correlations among the elements are complex. The content of nutrient in the Hangzhou Bay is higher than that in Xiangshan Bay and the content of nutrient in the Xiangshan Bay is higher than that in the Leqing Bay . The variation of the ratio of N/P is obvious. This reflects the aquatic chemical characteristics in the bay. Finally, this paper also discusses the reason why the aquatic chemical characteristics in the bays are unusual. 展开更多
关键词 Study of aquatic chemical characteristic in some bays along the coastal region of Zhejiang Province BAY
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