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Geostatistical Assessment of Pb,Zn and Cd Contamination in Near-Surface soils of the Urban-Mining Transitional Region of Isfahan,Iran

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Pedosphere 2010年第5期20卷 568-577页

作者： M.DAYANI J.MOHAMMADI department of soil Science Agriculture FacultyRamin Agriculture and Natural Resources University department of soil Science Agriculture FacultyShahrekord University

Due to the lack of regulation and environmental education and awareness,Sepahanshahr located in vicinity of Isfahan City,central Iran,is now a rapid growing residential area suffering from the considerable consequences of poorly regulated mining activities operating in its vicinity.A survey was carried out on soil Pb,Zn and Cd concentrations around Sepahanshahr Town to explore the spatial structure of Pb,Zn and Cd distribution and to map their concentrations using geostatistical techniques.100 near-surface soil samples were collected and analyzed for Pb,Zn and Cd and some related soil physical and chemical variables such as pH,organic matter content,electrical conductivity,and clay,silt and sand *** variography results showed a strong spatial dependency in heavy metals concentration due to the dilution effects of natural factors including atmospheric dispersion and *** almost same range values calculated for both ln-transformed Pb and sand data suggested presence of spatial ***,ln-transformed Zn data showed a shorter spatial dependency among the three tested heavy *** maps of all three heavy metals showed a strong gradient of contamination around the three mining sites activating in the *** results of this study provide insight into identification of the extent and spatial variability of Pb,Zn and Cd pollution in the mining sites and surrounding urban areas.

关键词：地表土壤城市地区镉污染地统计学伊朗过渡区重金属含量铅

Synthesis and comparative study of reactivities of δ-lactone,estor group and oxazinone ring in coumarin derivatives towards carbon or nitrogen nucleophiles

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Chinese Journal of Chemistry 1990年第5期8卷 469-473页

作者： EL-KAFRAWY,A.F. SOLIMAN,A.Y. BAKER,H.M. MOHAMED,F.K. EL-KADY,M.Y.department of Chemistry,faculty of Science,ain shams university and faculty of Education at El-Fayoum,Cairo.egypt department of Chemistry Faculty of Science Ain Shams University and Faculty of Education at El‐Fayoum Cairo Egypt

Condensation of methyl 7-methylcoumarin-4-acetate(2)with primary amines and with an- thranilic acid gave 7-methyl-2-oxo-N-aryl-2H-[1]-benzopyran-4--acetamide(4a—d)and(7),respectively. Compound 7 underwent cyclization to give 2-(7-methyl-2-oxo-2H-[1]-benzopyran-4-yl)-methyl-4H-3,1- benzoxazin-4-one(3).The reaction of 3 with aromatic amines gave the corresponding quinazolone derivatives 5 which tautomerises to the thermodynamically more stable isomer 6,whereas its reaction with Grignard reagents and aromatic aldehydes gave 8a,8b,and 9a,9b,respectively.

关键词： Synthesis and comparative study of reactivities of lactone,estor group and oxazinone ring in coumarin derivatives towards carbon or nitrogen nucleophiles ring

A novel 2-C reactivity studies of 1-aroyl-l,2dihydro-3H-naphtho[2,1-b]pyran-3-ones

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Chinese Journal of Chemistry 1990年第5期8卷 446-450页

作者： EL-KASABY,M.A. HASSAN,M.A. SHIBA,S.A. ABOU-EL-REGAL,M.M.department of Chemistry,faculty of Science,ain shams university,Cairo,egypt

The 2-C,methylene group of 1-aroyl-1,2-dihydro-3H-naphtho[2,1-b]pyran-3-ones (2)have been showed to possess a superior reactivity towards many of organic *** na- phthopyrones(2)condensed with aromatic aldehydes to give the 2-arylidine derivatives(3).Bromin- ation of 2 gave 1,2-dibromo(4)or 5-bromo(5)derivatives depending on the reaction conditions. The base catalyzed addition or cycloaddition of naphthopyrones(2)to 4-methoxy benzalacetophenone gave the expected Michael adduct(6)or the cyclic adducts(7-9)depending on the type of catalytic base and reaction *** of the products have been established by elemental analyses, IR and ~1H NMR spectroscopic methods.

关键词： CDC A novel 2-C reactivity studies of 1-aroyl-l,2dihydro-3H-naphtho[2,1-b]pyran-3-ones 占一

Accumulation of heavy metals in two crop seeds due to soil contamination as determined by neutron activation analysis techniques

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Journal of Environmental Sciences 1998年第2期10卷 118-124页

作者： M.F.Abdel Sabour soil and Water department, Nuclear Research Center, Cairo, egypt A.S.Abdel Haleem Hot Lab’s Center, Atomic Energy Authority, Cairo, egypt A.Sroor, N.Abdel Baset Nuclear Physics Lab, Girls faculty, ain shams university, egypt R.A.Zaghloul Mubarak City for Scientific Research and Technology, egypt

Samples of two crop seeds (corn and sesame) grown on different contaminated soil sources were collected and prepared for neutron activation analysis. soil contamination sources were organic waste compost applied to soil amendments namely, sewage sludge(Bs) and municipal solid waste (MSW) at 4%, 6% and 8% respectively. The non destructive NAA technique was used to determine some trace elements accumulation in plant seeds. Results revealed that increasing rate of tested organic waste resulted in dramatic increase in tested heavy metals levels in seeds(i.e., Fe, Zn, Co, Cr, Sc and Hg). Sesame seeds showed higher affinity to accumulate trace elements than corn grains in most tested elements. Moreover, MSW addition enhanced the accumulation of tested metals in seeds more than Bs compost.

关键词： heavy metals crop seeds neutron activation analysis techniques.

Production of hydrogen from fossil fuel:A review

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Frontiers in Energy 2023年第5期17卷 585-610页

作者： shams ANWAR Xianguo LI Laboratory for Fuel Cell and Green Energy Department of Mechanical and Mechatronics EngineeringUniversity of WaterlooWaterlooOntario N2L3G1Canada

Production of hydrogen,one of the most promising alternative clean fuels,through catalytic conversion from fossil fuel is the most technically and economically feasible *** conversion of natural gas into hydrogen and carbon is thermodynami-cally favorable under atmospheric ***,using noble metals as a catalyst is costly for hydrogen production,thus mandating non-noble metal-based catalysts such as Ni,Co,and Cu-based *** paper reviews the various hydrogen production methods from fossil fuels through pyrolysis,partial oxidation,autother-mal,and steam reforming,emphasizing the catalytic production of hydrogen via steam reforming of *** multicomponent catalysts composed of several non-noble materials have been *** the Ni,Co,and Cu-based catalysts investigated in the literature,Ni/Al_(2)O_(3)catalyst is the most economical and performs best because it suppresses the coke formation on the *** avoid carbon emission,this method of hydrogen production from methane should be integrated with carbon capture,utilization,and storage(CCUS).Carbon capture can be accomplished by absorption,adsorption,and membrane separation *** remaining challenges,prospects,and future research and development directions are described.

关键词： methane catalytic conversion natural gas hydrogen production CCUS

Diffusion of Chloride Ions in soils:*** of soil Moisture, Bulk Density and Temperature

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Pedosphere 1997年第1期7卷 65-72页

作者： XU MINGGANG, ZHANG YIPING and LIU WEINING (department of soil Science and Agrochemistry, Northwestern agricultural university, Yangling, Shaanxi 712100 China) department of soil Science and Agrochemistry Northwestern Agricultural University Yangling Shaanxi 712100 China

Diffusion coefficients of chloride ions in four soils of different texture with varying effective moisture content and varying bulk density from 1.1 to 1.6 g cm3 under three different temperatures were determined by the diffusion-cell method using 36Cl-labelled CaCl2 solution. The results showed that activation energy decreased with water content, which indicated that the threshold for diffusion was lower at a higher soil moisture rate. Therefore, the diffusion coefficient (D) of chloride ions in soil increased consistently with soil moisture. Although a near linear increase in the diffusion coefficient with increasing soil moisture or bulk density in all the soils was observed, the increase rate in different soils was not the same. The D value increased with temperature, and with temperature increased by 10℃ in the range from 5 "C to 45℃ theD valve increased by 10%～30%, averaging about 20%.

关键词：氯化物离子扩散系数土壤容重土壤湿度温度

Ecological rebuilding and land reclamation in surface mines in Shanxi Province, China

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Journal of Environmental Sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1, BAI Zhong ke 2, GAO Lin 1 (1. Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China E\|mail: miaozewei@*** 2. department of soil Science, Shanxi agricultural university Taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in China. As land is under pressure in China, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in Shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in Shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

Genotypic Differences of Forage Crop Tolerance to Acid soils

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Pedosphere 1998年第4期8卷 337-342页

作者： YANG YUAI CHU XIANGYUN YANG XIAOE WANG KE and HE ZHENLI (department of soil Science and agricultural Chemistry, Zhejiang agricultural university, Hangzhou 310029China) department of soil Science and agricultural Chemistry Zhejiang Agricultural University Hangzhou 310029 China

Twenty eight species of forage crops were planted on acid soils derived from Quaternary red clay (pH 4.16)and red sandstone (pH 4.55) to study genotypic differences of the forage crops in tolerance to acid soils as affected by liming, phosporus and potassium fertilizer application. Eight forage species, Lolium multiflorum L., Brachiaria decumbens, Digitaria sumtisii, Melinis minutiflora, Paspalum dilatatum, Paspalum wettsteinii,Sataria viridis Beanv and Shcep’s Festuca, were highly tolerant to acid soils, and grew relatively well in the tested soils without lime application, whereas most of the other 20 tested forage species such as Lolium perenne L., Meadow Festuca and Trifolium pratense L. were intolerant to acid soils, showing retarded growth when the soil pH was below 5.5 and significant increase in dry matter yields by phosphrus fertilizer application at soil pH 6.0. Results showed that large differences in tolerance to acid soils existed among the forage species,and tolerance of the forage species to acid soils might be closely associated with their tolerance to Al and P efficiency.

关键词：酸性土壤草料庄稼磷肥钾肥 PH值铝

Israeli Water Achievements Today and Enlightenment to China

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Chinese Journal of Population,Resources and Environment 2008年第4期6卷 72-77页

作者： Sun Lei1,2, Xu Lanqing3 1. Institute of Environmental Science and Engineering, Ocean university of China, Qingdao Shandong 266100, China 2. department of soil and Water Sciences, faculty of agricultural, Food and Environmental Quality Sciences, the Hebrew university of Jerusalem, 76100, Israel 3. Logistics Group of Ocean university of China, Qingdao Shandong 266100, China Institute of Environmental Science and Engineering Ocean University of China Qingdao Shandong 266100 China department of soil and Water Sciences Faculty of Agricultural Food and Environmental Quality Sciences the Hebrew University of Jerusalem 76100 Israel Logistics Group of Ocean university of China Qingdao Shandong 266100 China

Despite the endemic drought, arid climate and associated limited freshwater resources, as well as difficult geopolitical realities, Israel can provide a reliable supply of high quality water to a rapidly growing population. The achievements of water supply in Israel can be summarized as water technologies (like water transportation and purification, desalination, wastewater treatment, effluent reuse, storm water catchment, control systems, rain enhancement and drip irrigation, etc.), water management and legislation as well as water industry. In view of the national concern regarding the quality and quantity of the water, the skills, technologies and know-how that Israel has accumulated in water supply and irrigation can give us enlightenment that is also presented in this paper.

关键词：以色列水资源饮用水资源管理生态系统