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Darcy's Law Expressed by Chemical Index 被引量:1
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作者 Hu Kuanrong Cao Yuqing Zhang Wenbing Hu Zhongyi Department of Hydrogeology and Engineering Geology, Changchun University of Science and Technology, Changchun 130026 《Journal of Earth Science》 SCIE CAS CSCD 2000年第4期44-49,共6页
The Darcy's formula expressed by chemical indexes (ion activity a and saturation index β) is derived with the aid of the kinetics of multi-mineral dissolution. The implication of the formula and the relationship ... The Darcy's formula expressed by chemical indexes (ion activity a and saturation index β) is derived with the aid of the kinetics of multi-mineral dissolution. The implication of the formula and the relationship between the formula and the original Darcy's law expressed by hydraulic index (hydraulic gradient, Ⅰ) are discussed here. An analytic expression is established in this paper for the determination of the residence time of groundwater by chemical indexes, whose equivalence to isotopic age is studied. The formulas are derived from the calculation of permeability coefficient (K), conductivity coefficient (T) and actual velocity of groundwater (U). Finally, this paper introduces hydrogeological chemical kinetics constant (k j) and its determination method, differential and integral equations for chemical kinetics of groundwater in three-dimensional space. 展开更多
关键词 Darcy's formula chemical index ion activity saturation index.
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Chemical indexes of Paleoproterozoic sedimentary rocks from Liaohe Group,North China Craton:Implications for paleoclimate and provenance
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作者 ZHANG Wei LI Zhuang +4 位作者 YANG Fan PEI Fuping LIU Jin WANG Junhui WANG Zhiwei 《Global Geology》 2021年第2期71-79,共9页
Paleoproterozoic supracrustal materials have been widely identified in North China Craton,such as the Liaohe-,Hutuo-and Lyuliang groups.The Liaohe Group in the eastern part of the North China Craton is dominated by de... Paleoproterozoic supracrustal materials have been widely identified in North China Craton,such as the Liaohe-,Hutuo-and Lyuliang groups.The Liaohe Group in the eastern part of the North China Craton is dominated by deformed and metamorphosed sedimentary and volcanic successions.Compared with that of the coeval volcanic rocks,geochemistry of the sedimentary rocks from the Liaohe Group has rarely been studied in detail,which can possibly provide information on the paleoclimate and provenance.The authors analyzed the whole-rock and detrital zircon geochemistry of sedimentary rocks from the Liaohe Group against a uniform process and proposed their different ways of paleoweathering of the lower and upper formations.That is to say,although the lower and upper formations within the Liaohe Group might be derived from the similar source composition in a tectonically active setting,the paleoclimate that they experienced was not exactly the same.The predominant derivations are the Paleoproterozoic granitoids and basalts within the Liaohe Group,with minor input of Archean continental crust.This study highlights the contributions of the Paleoproterozoic mafic sources,which has been generally overlooked in the previous researches. 展开更多
关键词 Liaohe Group PALEOPROTEROZOIC chemical index PALEOCLIMATE PROVENANCE
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The atom-bond connectivity index of chemical bicyclic graphs 被引量:4
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作者 CHEN Jin-song GUO Xiao-feng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第2期243-252,共10页
The atom-bond connectivity(ABC) index provides a good model for the stability of linear and branched alkanes as well as the strain energy of cycloalkanes,which is defined as ABC(G) =∑ uv∈E(G) √d u+dv-2 dudv,... The atom-bond connectivity(ABC) index provides a good model for the stability of linear and branched alkanes as well as the strain energy of cycloalkanes,which is defined as ABC(G) =∑ uv∈E(G) √d u+dv-2 dudv,where du denotes the degree of a vertex u in G.A chemical graph is a graph in which no vertex has degree greater than 4.In this paper,we obtain the sharp upper and lower bounds on ABC index of chemical bicyclic graphs. 展开更多
关键词 atom-bond connectivity index chemical bicyclic graph bound.
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CHINESE CHEMICAL LETTERS AUTHOR INDEX
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《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第12期1646-1656,共11页
关键词 LIN DAI CHINESE chemical LETTERS AUTHOR index BAI CAI REN HE
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Chinese Journal of Chemical Engineering Author Index to 2005
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《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第6期853-860,共8页
关键词 LI OVER HE Chinese Journal of chemical Engineering Author index to 2005 NG
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CHINESE CHEMICAL LETTERS SUBJECT INDEX
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《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第12期1627-1645,共19页
关键词 HE CHINESE chemical LETTERS SUBJECT index
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Chinese Journal of Chemical Engineering Subject index to 2005
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《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第6期861-870,共10页
关键词 Chinese Journal of chemical Engineering Subject index to 2005
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GIS-Based Assessment of Soil Chemical and Physical Properties as a Basis for Land Reclamation in Toshka Area, Aswan, EGYPT
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作者 Ahmed A. M. Awad Mostafa M. A. Al-Soghir 《Open Journal of Geology》 2023年第7期697-719,共23页
The accurate assessment of soil properties is a crucial factor for composing and implementing reclamation plans. The main objective of this study was to evaluate soil chemical and physical properties and calculate the... The accurate assessment of soil properties is a crucial factor for composing and implementing reclamation plans. The main objective of this study was to evaluate soil chemical and physical properties and calculate the chemical and fertility index for assisting land reclamation in Toshka area. The Toshka area is located between latitudes 31°32'N and 31°36'N and longitudes 32°40'E and 32°60'E. GIS was used to select 16 sites. The results revealed the soil has undesirable characteristics. The soil pH ranged from slightly alkaline to moderately alkaline. Furthermore, it was characterized as saline (with a ECe of 4.65 - 11.45 dS⋅m<sup>−1</sup>) and moderately calcareous soil (with CaCO<sub>3</sub> at 11.85% - 17.20%). The soil had a low soil organic matter content which did not exceed 0.18%. The soil was dominated by a sandy loam texture (62.50%) followed by a sandy clay loam texture (18.75%). The bulk density, total soil porosity and saturated hydraulic conductivity values varied with 1.38 - 1.55 Mg⋅cm<sup>−3</sup>, 41.85% - 48.45% and 1.20 - 3.34 cm⋅h<sup>−1</sup>, respectively. The chemical index ranged from low to moderate quality. The correlations between the parameters osculated between negative and positive. Therefore, the soil may be reclaimed if the soil properties are improved and crop selection is optimized for this soil. 展开更多
关键词 Land Reclamation Soil chemical and Physical Properties chemical Quality index Fertility Quality index
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Analysis of Physical and Chemical Indices and Quality of Blueberry Wines from Gardenblue and Baldwin
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作者 Hai LIU Yi OU Shunqiao LIU 《Agricultural Biotechnology》 CAS 2018年第4期200-202,共3页
Gardenblue and baldwin rabbiteye blueberry are the alien varieties. The physical and chemical indices of the fresh fruits of the two varieties were analyzed. The results showed that the sugar-acid ratio was higher in ... Gardenblue and baldwin rabbiteye blueberry are the alien varieties. The physical and chemical indices of the fresh fruits of the two varieties were analyzed. The results showed that the sugar-acid ratio was higher in gardenblue than in baldwin, and the content of anthocyanins was also higher in gardenblue than in baldwin, so the quality of gardenblue was better. The gardenblue wine has better quality than the baldwin wine, and the two kinds of wines both have good quality. Therefore, gardenblue and baldwin both are suitable for the brewing red wine as the raw material. 展开更多
关键词 Gardenblue BALDWIN blueberry wine Physical and chemical index QUALITY
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Geochemical Characterization of Organic Rich Black Rocks of the Niutitang Formation to Reconstruct the Paleoenvironmental Settings during Early Cambrian Period from Xiangxi Area,Western Hunan,China
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作者 Rizwan Sarwar Awan Chenglin Liu +5 位作者 Ashar Khan Khawaja Hasnain Iltaf Qibiao Zang Yuping Wu Sajjad Ali Muhammad Amar Gul 《Journal of Earth Science》 SCIE CAS CSCD 2023年第6期1827-1850,共24页
The Niutitang Formation in the South China Block might be a source of hydrocarbon as it contains an enormous quantity of organic matter.Black rock of the Early Cambrian Niutitang Formation is widely distributed in the... The Niutitang Formation in the South China Block might be a source of hydrocarbon as it contains an enormous quantity of organic matter.Black rock of the Early Cambrian Niutitang Formation is widely distributed in the Yangtze region,but detailed geochemical understanding of it is still emerging.This research discusses the detailed geochemical characteristics of the Niutitang Formation to reconstruct the paleoenvironmental conditions,employing total organic carbon(TOC)content,major,trace,and rare earth element data.For this purpose,black rock specimens of the Niutitang Formation from two outcrop sections were utilized for geochemical characterization,and the results compared with another eight sections from the South China Block.The average total organic carbon in these sediments is significantly higher(5.80 wt.%).In the platform region,lower quantities of TOC indicate a poor potential to produce hydrocarbons.At the same time,significantly higher TOC is observed in the deep shelf and slope sediments,indicating a significant potential to produce hydrocarbons.The average Ce,Eu and Y anomalies from both Longbizui and Sancha sections studied are 0.74,0.86,1.77,1.07,and 1.19,1.30,respectively.The chemical index of alteration(CAI)throughout the Yangtze block is higher(averaging 71.32)than that of Post Archean Australian Shale(PAAS 69),indicating a moderately weathered source of the Niutitang Formation relative to PAAS.As the sediments are moderately weathered,this suggests these rocks might have been derived from felsic rocks,mainly granite-granodiorite.The normalization of REEs in the black rocks reveals a reduction of light REEs with increase in heavy REEs enrichment.Similarly,a positive Eu anomaly,negative Ce anomaly,and a moderate Y/Ho(34.61)are clues to a hybrid depositional mechanism associated with hydrothermal action and terrigenous input.These anomalies are also evidence of upwelling in the paleo-ocean and mixing of organic matter,which created anoxic bottom water during the deposition of the Niutitang Formation in the basin and upper oxic water conditions before deposition.The main controlling factors for the distribution of rare earth elements in these black rocks of the Niutitang Formation are pH,terrigenous input,source rock composition,tectonism,an upwelling mechanism,and hydrothermal activity. 展开更多
关键词 anomaly paleo-ocean PALEOENVIRONMENT chemical index ALTERATION WEATHERING meta-somatism sediments
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Effect of Dehulling and Hydrothermal Treatment on the Amino Acid Content of Soriz (<i>Sorghum oryzoidum</i>) 被引量:1
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作者 Rodica Siminiuc Lidia Coșciug 《Food and Nutrition Sciences》 2021年第12期1232-1242,共11页
Cereals are the basic element in ensuring the food security of the population through the significant intake of carbohydrates, proteins, dietary fiber, vitamins and minerals. The processing of cereals leads to changes... Cereals are the basic element in ensuring the food security of the population through the significant intake of carbohydrates, proteins, dietary fiber, vitamins and minerals. The processing of cereals leads to changes in their nutritional quality, which could lead to both reduced nutrients and anti-nutrients. Gluten-free cereal varieties attract attention as raw materials to improve the nutritional quality of food and to diversify the product range. Sorghum (<i>Sorghum</i><span> <i>oryzoidum</i></span>) is a hybrid of sorghum, obtained at the Institute for Scientific Research for Corn and Sorghum in the Republic of Moldova, by crossing Sudan grass (<i>S</i><span>. <i>sudanense</i></span>) and bicolor sorghum (<i>S</i><span>. <i>bicolor</i></span>). The research aimed to determine the impact of dehulling and hydrothermal treatment on the amino acid content of soriz. The obtained results reported that the dehulling and hydrothermal treatment led to the uneven modification of the amino acid content in the investigated samples. As a result of dehulling, the total amount of essential amino acids decreased by 19.8% compared to the native grain. Boiling whole grains without prior hydration led to <span>34% loss of essential amino acids compared to native grains, and pre-hydration</span> of the grains and subsequent boiling reduced essential amino acid losses by 8% compared to cooked grains without hydration. Boiling grains with pre-hydration had a positive effect on the chemical index of lysine, methionine and cysteine, leucine and tryptophan. However, the nutritional quality of sorghum grain proteins and derivatives obtained, evaluated according to the chemical index, is low. The results obtained reported that dehulling and hydrothermal treatment unevenly altered the amino acid content, and the method of boiling grains with pre-hydration had a positive effect on the CSI of lysine, methionine and cysteine, leucine and tryptophan. 展开更多
关键词 Soriz DEHULLING Hydrothermal Treatment Amino Acids chemical Score index
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Implications of multipurpose tree leaf application on wheat productivity in dry tropics
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作者 Rajani Srivastava K.P.Singh 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第4期777-782,共6页
Leaves of multipurpose tree species (those providing more than one function or product of human use) can serve as sources of fer- tilizer for nutrient supply, especially nitrogen (N). In this study chopped leaves ... Leaves of multipurpose tree species (those providing more than one function or product of human use) can serve as sources of fer- tilizer for nutrient supply, especially nitrogen (N). In this study chopped leaves of tropical tree species (5 N-fixing species, 5 non-N-fixing species and combinations of 5 N-fixing with a non-N-fixing species) were in- corporated in soil to evaluate its effects on wheat biological productivity (including grain yield, GyIELD) under dryland conditions. High quality leaves of N-fixing tree species (e.g. Dalbergia sissoo, Cassia fistula and Prosopis cineraria) had lower carbon/nitrogen (C/N), lignin/nitrogen (L^o/N), polyphenol/nitrogen (PPt/N) and lignin+polyphenol /nitrogen (L~+PpL/N) ratios than low quality leaves of non-N-fixing species. Com- bination treatments had intermediate values of different parameters, Application of high quality leaves caused greater increases in wheat productivity and yield than other species. 展开更多
关键词 multipurpose tree leaves chemical quality index grain yield N-fixing species non-N fixing species Dryland agriculture
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Growth of large-area aligned pentagonal graphene domains on high-index copper surfaces 被引量:2
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作者 Kailun Xia Vasilii I. Artyukhov +4 位作者 Lifei Sun Jingying Zheng Liying Jiao Boris I. Yakobson Yingying Zhang 《Nano Research》 SCIE EI CAS CSCD 2016年第7期2182-2189,共8页
Single-crystal graphene domains grown by chemical vapor deposition (CVD) intrinsically tend to have a six-fold symmetry; however, several factors can influence the growth kinetics, which can in turn lead to the form... Single-crystal graphene domains grown by chemical vapor deposition (CVD) intrinsically tend to have a six-fold symmetry; however, several factors can influence the growth kinetics, which can in turn lead to the formation of graphene with different shapes. Here we report the growth of oriented large-area pentagonal single-crystal graphene domains on Cu foils by CVD. We found that high-index Cu planes contributed selectively to the formation of pentagonal graphene. Our results indicated that lattice steps present on the crystalline surface of the underlying Cu promoted graphene growth in the direction perpendicular to the steps and finally led to the disappearance of one of the edges forming a pentagon. In addition, hydrogen promoted the formation of pentagonal domains. This work provides new insights into the mechanism of graphene growth. 展开更多
关键词 pentagonal graphene copper foil high index plane chemical vapor deposition large area
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