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Exploring Nutritional Compositions,Volatile Compounds,Health Benefits,Emerging Processing Technologies,and Potential Food Products of Glutinous Rice:A Review
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作者 Maimunah Mohd ALI Norhashila HASHIM 《Rice science》 SCIE CSCD 2024年第3期251-268,共18页
Glutinous rice(Oryza sativa var.glutinosa)stands out as one of the most popular rice varieties globally,amidst thousands of rice cultivars.Its increasing popularity is attributed to its rich nutritional compositions a... Glutinous rice(Oryza sativa var.glutinosa)stands out as one of the most popular rice varieties globally,amidst thousands of rice cultivars.Its increasing popularity is attributed to its rich nutritional compositions and health benefits.This review aims to summarize the nutritional compositions,volatile compounds,and health benefits of glutinous rice.Further,in-depth studies are necessary to explore the utilization of glutinous rice in enhancing processing technologies and developing new food products.Glutinous rice has been shown to possess numerous health benefits,including antioxidant activity,bioactive compounds,anti-cancer properties,anti-inflammatory effects,anti-diabetic potential,and cholesterol-lowering effects.Besides its nutritional compositions,the major volatile compounds identified in glutinous rice could serve as a functional food for human consumption.Emerging processing technologies related to glutinous rice are elaborated to improve the latest developments for incorporating them into various food products. 展开更多
关键词 glutinous rice health benefit volatile compound nutritional composition processing technology
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Chemical Compositions of Volatile Oil from Fruiting Body of Armillaria luteo-virens 被引量:30
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作者 周劲松 熊辉岩 +2 位作者 杨春江 焦迎春 盛海彦 《Agricultural Science & Technology》 CAS 2008年第2期90-92,共3页
The chemical compositions of volatile oil from fruiting body of Armillaria luteo-virens in Qinghai Province were firstly analyzed with GC-MS and its relevant compositions were detected by calculating chromatographic p... The chemical compositions of volatile oil from fruiting body of Armillaria luteo-virens in Qinghai Province were firstly analyzed with GC-MS and its relevant compositions were detected by calculating chromatographic peak area with normalized method. 21 peaks were separated and 13 compositions were identified which were mainly unsaturated fatty acids, taking 97.1% of the total volatile oil. 展开更多
关键词 Armillaria luteo-rirens Volatile oil Chemical compositions GC-MS
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Functional evaluation for effective compositions in seed oil of Korean pine 被引量:11
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作者 王振宇 陈小强 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第3期215-217,共3页
The effect of seed oil of Korean pine (Pinus koraiensis) on the rats' blood-fat and its anti-ageing function was stud-ied for appraising the efficacy of the seed oil of Korean pine. Sixty experimental rats were ra... The effect of seed oil of Korean pine (Pinus koraiensis) on the rats' blood-fat and its anti-ageing function was stud-ied for appraising the efficacy of the seed oil of Korean pine. Sixty experimental rats were randomly divided into 5 groups (half males and half females in each group) as normal control group, high fat diet control group, and three groups (Group 1 Group 2, Group 3) that were fed with feedstuff with the contents of the seed oil of 2.0g/(kgd-1), 4.0g/(kgd-1) and 8.0g/(kgd-1), respec-tively. The indexes such as superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and anti-oxidation capacity (AOC) were measured by Reagent Kit method. It was found that the seed oil of the Korean pine could reduce the content of triglyc-eride and improve SOD as well as GSH-PX activity in serum. These indexes of the rats in Group 2 fed with Korean pine seed oil of 4.0 g/(kgd-1) reached the significant level and those of rats in Group 3 fed with the seed oil of 8.0 g/(kgd-1) reached the extremely significant level. The results indicated the seed oil of Korean pine had function of regulating the level of blood-fat and anti-ageing. 展开更多
关键词 Korean pine seed oil Effective compositions Functional evaluation Blood-fat ANTI-AGEING
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Research on Nourishing Compositions of Fagopyrum tataricum 被引量:2
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作者 宋毓雪 黄凯丰 《Agricultural Science & Technology》 CAS 2010年第9期115-117,共3页
[Objective] The aim was to identify the nourishing compositions of Fagopyrum tataricum and screen high-quality buckwheat materials.[Method]A total of 10 species of buckwheat including T32,T31,T30,T14,T28,T23,T24,Jiuji... [Objective] The aim was to identify the nourishing compositions of Fagopyrum tataricum and screen high-quality buckwheat materials.[Method]A total of 10 species of buckwheat including T32,T31,T30,T14,T28,T23,T24,Jiujiang Buckwheat,Weiku 2 and WK-1 were employed as experimental materials,and the contents of the nutritional components(including total sugar,reducing sugar,starch,amylose,amylopectin and protein),flavonoids content,physical and chemical characteristics(such as expansive force,water holding capacity)of them were respectively measured.[Result]There were significant differences in contents of soluble protein,total sugar,reduced sugar,amylase and expansive force among the cultivars,but the differences in contents of total starch,amylopectin,flavonoids content and water holding capacity were not significant.[Conclusion]The starch content in seeds of buckwheat was relatively high,and amylopectin was the main composition. 展开更多
关键词 BUCKWHEAT Nourishing compositions Physical and chemical characteristics
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Nutritional Compositions of Maca Grown in Ebian and HPLC Fingerprints of Macaene and Macamide
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作者 陈建 夏陈 +1 位作者 朱永清 栢凤女 《Agricultural Science & Technology》 CAS 2016年第4期947-950,共4页
In the present study, the nutritional compositions of maca which was grown in a mountain area at an elevation of 2 200-2 800 m of Ebian County,Sichuan Province were measured, and then HPLC analysis on two representati... In the present study, the nutritional compositions of maca which was grown in a mountain area at an elevation of 2 200-2 800 m of Ebian County,Sichuan Province were measured, and then HPLC analysis on two representative active compounds(macaene and macamide) in the maca sample was performed.The results revealed that there were 24.20% total protein, 18.40% total amino acids(including 3.84% arginine), 42.80% total sugars, 1.36% fat and kinds of minerals(including 1.14% potassium) in Ebian maca. HPLC fingerprints of macaene and macamide of Ebian maca were similar to those of Peru maca. The results suggested that maca could be cultivated with good quality in some mountain areas with an altitude1 000 m lower than the origin place in Peru. 展开更多
关键词 MACA Nutritional compositions Macaene Macamide HPLC fingerprints
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Inheritance of Fat and Fatty Acid Compositions in Peanut (Arachis hypogaea L.) 被引量:5
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作者 张新友 祝水金 +6 位作者 韩锁义 徐静 刘华 汤丰收 董文召 臧秀旺 张忠信 《Agricultural Science & Technology》 CAS 2011年第7期943-946,974,共5页
[Objective] The aim was to explore the inheritance of fat and fatty acid compositions in peanut.[Method] Genetic and correlation analyses were performed using a mixed genetic model of major gene plus polygene with 215... [Objective] The aim was to explore the inheritance of fat and fatty acid compositions in peanut.[Method] Genetic and correlation analyses were performed using a mixed genetic model of major gene plus polygene with 215 F9 RILs and their parents ZHENG 8903 and YUHUA No.4.[Result] The optimal genetic model of the fat content was two linked complementary major gene plus polygene inheritance model.The heritability of major genes was 22.88%.Oleic,linoleic,and palmitic acid content were controlled by two major genes and the heritability was 75.11%,75.00% and 60.95%,respectively.Stearic and arachidic acid content were controlled by two major genes plus polygenes,the heritability of major genes was 26.43% and 33.17%,respectively.O/L ratio and behenic acid content were controlled by three major genes,the heritability was 70.65% and 30.70%,respectively.[Conclusion] The result in this study was that accumulating polygenes should be emphasized in the improvement of fat content,while utilization of major genes is enhanced in improvement of oleic and linoleic acids. 展开更多
关键词 PEANUT FAT Fatty acid composition INHERITANCE
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Advances in Research on Triterpenoids and Volatile Compositions of Kudingcha
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作者 杨刚劲 黄艳 +2 位作者 郑金燕 赖茂祥 刘布鸣 《Agricultural Science & Technology》 CAS 2014年第6期1012-1014,共3页
Kudingcha, a commonly used traditional Chinese medicine, has multiple functions in anti-radiation, anti-aging, quickening the blood vessels, reducing blood lipid and blood pressure and so forth. Therefore, this articl... Kudingcha, a commonly used traditional Chinese medicine, has multiple functions in anti-radiation, anti-aging, quickening the blood vessels, reducing blood lipid and blood pressure and so forth. Therefore, this article reviews the origins of Kudingcha, and analyzes the major triterpenoids and volatile chemicals, with an at- tempt to provide more references for the development and utilization of Kudingcha. 展开更多
关键词 KUDINGCHA ORIGIN TRITERPENOIDS VOLATILE Chemical compositions
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Study on Main Chemical Compositions of Rice Straw in Three Different Areas of Jiangsu Province 被引量:1
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作者 宋卫东 王教领 +3 位作者 王明友 吴今姬 李尚昆 王培雨 《Agricultural Science & Technology》 CAS 2016年第2期405-408,共4页
[Objective] The research was aimed to study the main chemical composi- tions of rice straw in the three different areas of Jiangsu Province. [Method] The cellulose, hemicellulose, lignin and crude ash of rice straw co... [Objective] The research was aimed to study the main chemical composi- tions of rice straw in the three different areas of Jiangsu Province. [Method] The cellulose, hemicellulose, lignin and crude ash of rice straw collected in Huaian, Changzhou and Zhenjiang of Jiangsu Province during 2011-2013 were determined. [Result] The change trends of cellulose and hemicellulose in three arrears in differ- ent years were consistent. The cellulose content increased after falling, and hemi- cellulose content presented declining tendency. The lignin content of rice straw fist rose then declined in Huaian and Changzhou in different years, while it presented the declining tendency in Zhenjiang. The ash content of rice straw changed little and was all less than 65% in the three areas in different years. And the chemical composition of rice straw changed significantly in different years. [Conclusion] The research could provide basis for high added-value use of crop straw. 展开更多
关键词 Rice straw Different years Chemical composition Jiangsu Province
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Comparison on the Chemical Compositions in the K326 Tobacco from Different Tobacco-planting Areas of Yunnan Province 被引量:11
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作者 王岚 杨继周 +8 位作者 蒋美红 段俊杰 卢叶 敖金成 马彦清 李继飞 王涛 林楠 邓国宾 《Agricultural Science & Technology》 CAS 2012年第1期139-142,共4页
[Objective] To compare the regional differences of the conventional chemi- cal compositions in the K326 B2F tobacco from different tobacco-planting areas of Yunnan Province. [Methed] Continuous flow analyzer was used ... [Objective] To compare the regional differences of the conventional chemi- cal compositions in the K326 B2F tobacco from different tobacco-planting areas of Yunnan Province. [Methed] Continuous flow analyzer was used to detect the con- ventional chemical compositions, and SPSS 17.0 statistical package was used to conduct data statistical analysis and variance analysis. [Result] Significant differences were existed among most of the indicators for conventional chemical compositions of K326 tobacco in different areas: the differences of total sugar, reducing sugar and nicotine reached a high Significant level; potassium ion and total nitrogen differences reached a significant level, while there was no significant difference in chlorine ion. Most of the conventional chemical compositions in K326 B2F tabacco planted in Yuxi region and those planted in Qujing, Dali and Chuxiong were significantly different. The total sugar, reducing sugar and nicotine contents of tobacco planted in eastern Yunnan, central Yunnan and western Yunnan were significantly different; while the conventional chemical compositions contents in the tobacco planted in Chuxiong and Dali, which all belong to western Yunnan, showed no obvious significant difference, indicating different ecological environments in large area had a great impact on the tobacco of Yunnan Province. [Conclusion] It revealed the regional characteristics of the conventional chemical compositions in K326 flue-cured tobacco leaves from Yunnan Province, providing references for the cigarette blending and production of high-quality tobacco with characteristics. 展开更多
关键词 K326 B2F Conventional chemical compositions DIFFERENCE
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Petrogenesis and Tectonic Significance of the Xiuwacu Two-Period Magmatism in Geza Arc of Yunnan Province: Constraints from Lithogeochemistry, Zircon U-Pb Geochronology and Hf isotopic Compositions 被引量:6
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作者 LAI Anqi LI Zhe +1 位作者 LIU Xuelong LI Yang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第2期757-758,共2页
Objective The Late Cretaceous Xiuwacu ore-bearing porphyry is located in the Geza area of southern Yidun arc, SW China. In this area, the rock mass is mainly composed of three lithofacies: biotite granite porphyry, ... Objective The Late Cretaceous Xiuwacu ore-bearing porphyry is located in the Geza area of southern Yidun arc, SW China. In this area, the rock mass is mainly composed of three lithofacies: biotite granite porphyry, monzonitic granite and light alkali feldspar granite. As a part of the Yidun arc, the Geza arc has common structure and temporal- spatial evolution with the ~idun arc, which has experienced three stages of oceanic crust subduction, collision orogeny and intracontinent convergence stages. The molybdenite ores in the area are mainly hosted in monzonitic granite-porphyry and structural fracture zone, and the ore bodies are strictly controlled by faults. In recent years, great geological prospecting results have been achieved in Xiuwacu, and the deposit has reached a medium scale. However, there are few researches on the metallogenic porphyry. Based on the previous research, we determined the rock-forming and ore-forming age of the porphyry, and found that there were two stages of magmatism intrusion in Xiuwacu: Indosinian and Yanshanian. We also discussed the geochemical characteristics and source area of the rocks in the area. 展开更多
关键词 Hf Constraints from Lithogeochemistry Petrogenesis and Tectonic Significance of the Xiuwacu Two-Period Magmatism in Geza Arc of Yunnan Province Zircon U-Pb Geochronology and Hf isotopic compositions Pb
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Influence of contamination on banded iron formations in the Isua supracrustal belt, West Greenland: Reevaluation of the Eoarchean seawater compositions 被引量:3
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作者 Shogo Aoki Chiho Kabashima +2 位作者 Yasuhiro Kato Takafumi Hirata Tsuyoshi Komiya 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第4期1049-1072,共24页
Banded Iron Formations(BIFs) are chemical sediments, ubiquitously distributed in the Precambrian supracrustal belts; thus their trace element compositions are helpful for deciphering geochemical evolution on the Ear... Banded Iron Formations(BIFs) are chemical sediments, ubiquitously distributed in the Precambrian supracrustal belts; thus their trace element compositions are helpful for deciphering geochemical evolution on the Earth through time. However, it is necessary to elucidate factors controlling the whole-rock compositions in order to decode the ancient seawater compositions because their compositions are highly variable. We analyzed major and trace element contents of the BIFs in the 3.8-3.7 Ga Isua supracrustal belt(ISB), southern West Greenland. The BIFs are petrographically classified into four types:Black-,Gray-, Green-and White-types, respectively. The Green-type BIFs contain more amphiboles, and are significantly enriched in Co, Ni, Cu, Zn, Y, heavy rare earth element(HREE) and U contents. However,their bulk compositions are not suitable for estimate of seawater composition because the enrichment was caused by secondary mobility of metamorphic Mg, Ca and Si-rich fluid, involvement of carbonate minerals and silicate minerals of olivine and pyroxene and/or later silicification or contamination of volcanic and clastic materials. The White-type BIFs are predominant in quartz, and have lower transition element and REE contents. The Gray-type BIFs contain both quartz and magnetite. The Black-type BIFs are dominated by magnetite, and contain moderate to high transition element and REE contents. But,positive correlations of V, Ni, Zn and U contents with Zr contents suggest that involvement of detrital,volcanic and exhalative materials influences on their contents. The evidence for significant influence of the materials on the transition element contents such as Ni in the BIFs indicates the transition element contents in the Archean ocean were much lower than previously estimated. We reconstructed secular variations of V,Co, Zn and U contents of BIFs through time, which show Ni and Co contents decreased whereas V, Zn and U contents increased through time. Especially, the Ni and Co contents drastically decreased in the Mesoarchean rather than around the Great Oxidation Event. On the other hand, the V,Zn and U contents progressively increased from the Mesoarchean to the Proterozoic. Stratigraphical trends of the BIFs show increase in Y/Ho ratios and decrease in positive Eu anomaly upwards, respectively. The stratigraphic changes indicate that a ratio of hydrothermal fluid to seawater component gradually decrease through the deposition, and support the Eoarchean plate tectonics, analogous to the their stratigraphic variations of seafloor metalliferous sediments at present and in the Mesoarchean. 展开更多
关键词 Banded iron formations Eoarchean Isua supracrustal belt Bioessential elements Seawater compositions
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Age and Origin of Paleogene Granitoids from Western Yunnan Province,China:Geochemistry,SHRIMP Zircon Ages,and Hf-in-Zircon Isotopic Compositions 被引量:3
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作者 SHI Yuruo WU Zhonghai +2 位作者 Alfred KRoNER FAN Taoyuan YANG Zhenyu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第5期1601-1615,共15页
We report geochemical data, SHRIMP zircon ages and Hf-in-zircon isotopic compositions for Cenozoic granitoids from major fault systems in the Tethyan belt in western Yunnan Province, southwestern China.Four magmatic p... We report geochemical data, SHRIMP zircon ages and Hf-in-zircon isotopic compositions for Cenozoic granitoids from major fault systems in the Tethyan belt in western Yunnan Province, southwestern China.Four magmatic pulses occurred in the Paleogene, namely at ca.57 Ma, ca.50 Ma, 45–40 Ma, and 38–34 Ma.Early magmatism of this episode(57–50 Ma) produced S-type granites whose zircons yielded εHf(t) values of-5.0 to-0.3.In contrast, late magmatism of this episode reflects heterogeneous sources.Zircons from a granite porphyry along the Ailaoshan-Red River fault system have slightly positive εHf(t) values suggesting derivation from relatively young crust and/or a juvenile source.However, zircons from a granite along the Gaoligong fault system have strongly negative εHf(t) values and suggest derivation from a Paleoproterozoic crustal source.The composition of the granitoids varies with age(from ca.57 Ma to ca.34 Ma) from peraluminous to metaluminous and also suggests a change from syn-collisional to late-orogenic tectonic setting.A new tectonic model, impacting lithospheric wedge(ILW) is shown for the origin of Paleogene granitoids in this paper. 展开更多
关键词 PALEOGENE magmatism SHRIMP zircon ages Hf-in-zircon isotopic compositions western Yunnan
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Effects of Mg/PTFE pyrotechnic compositions on reignition characteristics of base bleed propellants and heating mechanism 被引量:3
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作者 Xiao-chun Xue Long-ze Ma Yong-gang Yu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第1期94-108,共15页
The effects of magnesium/polytetrafluoroethylene(Mg/PTFE)pyrotechnic compositions on the coupled flow field and reignition mechanism are important aspects governing the perfommance and range of base bleed projectiles(... The effects of magnesium/polytetrafluoroethylene(Mg/PTFE)pyrotechnic compositions on the coupled flow field and reignition mechanism are important aspects governing the perfommance and range of base bleed projectiles(BBPs).Owing to a decrease in pressure and temperature when the BBP leaves the muzzle,rapid depressurization occurs,which extinguishes the base bleed propellant.The Mg/PTFE py-rotechnic composition pressed in the igniter of the base bleed unit(BBU)provides additional energy to the BBU via a chemical reaction.Thus,the extinguished base bleed propellant is reignited under the effect of high-temperature combustion gas jets from the igniter.In this study,a numerical analysis is conducted to evaluate the effects of PTFE and Mg granularity as well as Mg/PTFE pyrotechnic compo-sitions.Owing to the rapid depressurization,the temperature and pressure was found to decrease fordifferent Mg/PIFE pyrotechnic compositions.However,the depressurization time increased as the PTFE granularity increased,the Mg granularity decreased,and the Mg content increased.When the pressure in the combustion chamber of the BBU decreased to the atmospheric pressure,the combustion gas jets from the igniter expand upstream(rather than downstream).However,these combustion gas jets exhibit different axial and radial expansion characteristics depending on the pyrotechnic compositions used,The results show that the reignition delay time,ta,of the base bleed propellant was 377.608,94.27,387.243,523.966,and 221.094 ms for cases A-E,respectively.Therefore,it was concluded that the Mg/PTFE pyrotechnic composition of case B was the most beneficial for the reignition of the base bleed propellant,with the earliest addition of energy and mass to the BBP. 展开更多
关键词 Thermal effect High-temperature combustion gas Mg/PTFE pyrotechnic compositions REIGNITION
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Origin of natural sulfur-metal chimney in the Tangyin hydrothermal field,Okinawa Trough:constraints from rare earth element and sulfur isotopic compositions 被引量:3
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作者 Hong Cao Zhi-lei Sun +3 位作者 Chang-ling Liu En-tao Liu Xue-jun Jiang Wei Huang 《China Geology》 2018年第2期225-235,共11页
For the first time,we present the rare earth element (REE)and sulfur isotopic composition of hydrothermal precipitates recovered from the Tangyin hydrothermal field (THF),Okinawa Trough at a water depth of 1206 m.The ... For the first time,we present the rare earth element (REE)and sulfur isotopic composition of hydrothermal precipitates recovered from the Tangyin hydrothermal field (THF),Okinawa Trough at a water depth of 1206 m.The natural sulfur samples exhibit the lowest ∑REE concentrations (∑REE= 0.65×10^-6-4.580×10^-6)followed by metal sulfides (∑REE=1.71×10^-6-11.63×10^-6).By contrast,the natural sulfur-sediment samples have maximum ∑REE concentrations (∑REE=1 1.54×10^-6-33.06×10^-6), significantly lower than those of the volcanic and sediment samples.Nevertheless,the δEu,δCe,(La/Yb)N, La/Sm,(Gd/Yb)N and normalized patterns of the natural sulfur and metal sulfide show the most similarity to the sediment.Most hydrothermal precipitate samples are characterized by enrichments of LREE (LREE/HREE=10.09-24.53)arid slightly negative Eu anomalies or no anomaly (δEu=0.48-0.99),which are different from the hydrothermal fluid from sediment-free mid-oceanic ridges and back-are basins,but identical to the sulfides from the Jade hydrothermal field.The lower temperature and more oxidizing conditions produced by the mixing between seawater and hydrothermal fluids further attenuate the leaching ability of hydrothermal fluid,inducing lower REE concentrations for natural sulfur compared with metal sulfide;meanwhile,the negative Eu anomaly is also weakened or almost absent.The sulfur isotopic compositions of the natural sulfur (δ^34S=3.20‰-5.01‰,mean 4.23 ‰)and metal sulfide samples (δ34S=0.82‰-0.89‰,mean 0.85‰)reveal that the sulfur of the chimney is sourced from magmatic degassing. 展开更多
关键词 Hydrothormal processes NATURAL SULFUR ISOTOPIC compositions REE Tangyin field OKINAWA TROUGH China
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Siderophile Element Compositions of Pyroxenes in HED Meteorites: Implications for the Differentiation of Magma Ocean on Vesta 被引量:2
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作者 CHEN Hongyi MIAO Bingkui +1 位作者 XIE Lanfang SHAO Huimin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期267-268,共2页
1 Introduction The howardite,eucrite and diogenite(HED)meteorites are ultramafic and mafic igneous rocks and impact-engendered breccias derived from a thoroughly differentiated asteroid 4 Vesta.Diogenites include duni... 1 Introduction The howardite,eucrite and diogenite(HED)meteorites are ultramafic and mafic igneous rocks and impact-engendered breccias derived from a thoroughly differentiated asteroid 4 Vesta.Diogenites include dunites, 展开更多
关键词 Co Siderophile Element compositions of Pyroxenes in HED Meteorites Implications for the Differentiation of Magma Ocean on Vesta
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Nutrient compositions of cultured Skeletonema costatum,Chaetoceros curvisetus,and Thalassiosira nordenskildii 被引量:1
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作者 潘胜军 沈志良 +3 位作者 刘文萍 韩笑天 苗辉 马海青 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1131-1138,共8页
We cultured different-sized fractions of dominant phytoplankton species, Skeletonema costatum, Chaetoceros curvisetus, and Thalassiosira nordenskioldii, collected in different sea areas in various seasons, and measure... We cultured different-sized fractions of dominant phytoplankton species, Skeletonema costatum, Chaetoceros curvisetus, and Thalassiosira nordenskioldii, collected in different sea areas in various seasons, and measured and compared their C, N, P, Si contents. The N content of these species is similar, while the C, P, and Si contents of S. costatum from eutrophic Changjiang (Yangtze River) estuary are higher than those from Jiaozhou Bay (JZB), particularly the content of Si. The C, N, P, and Si contents of cultured phytoplankton in JZB increase with size fraction augmentation, and the percentages of C, N, and P follow the same trend, while the percentage of Si remain constant. Moreover, S. costatum from small-sized fraction assimilated Si more easily than C. curvisetus and T. nordenskirldii, which is explained by the dominance of S. costatum under the conditions of low SiO3-Si concentration in JZB. The C, N, P, and Si contents of cultured S. costatum collected during summer and winter are higher, which is consistent with the phytoplankton blooming seasons in JZB. The SiO3-Si concentration of seawater during spring restrain the growth of phytoplankton, supported by the fact that the N, P, and Si contents and their ratios in cells of cultured S. costatum are low in spring season. 展开更多
关键词 nutrient compositions Skeletonema costatum Chaetoceros curvisetus Thalassiosira nordenskiOldii
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The Background of Regional Lead Isotopic Compositions and Its Application in the Lower and Middle Reaches of the Yangtze River and Neighbouring Areas 被引量:1
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作者 Ma Zhendong and Shan Guangxiang Geochemistry Institute, China University of Geosciences, Wuhan, Hubei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第2期158-170,共13页
The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of diff... The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of different geological formations and units are con-trolled by the primary mantle heterogeneity, dynamic process of crust-mantle interchange,abundances of uraninm, thorium and lead of various layers of the earth and timing. Studies onthe background of regional isotopic compositions may offer significant information forgeochemical regionalization, tracing of sources of ore-forming materials, and regionalprognosis of ore deposits. 展开更多
关键词 background of regional lead isotopic compositions tracing action lower and middle reaches of the Yangtze River and neighbouring areas
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Determination of the gas compositions for direct coal liquefaction by gas chromatography 被引量:1
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作者 Xiao-Man ZHU Pei-Lin LI Shu-Feng DU 《Journal of Coal Science & Engineering(China)》 2013年第4期535-539,共5页
Via multi-dimensional gas chromatography, configured with parallel dual-channel, double detectors, valves switching and back flushing, rapid analysis of the gas compositions consisting of C1-C5 hydrocarbons and perman... Via multi-dimensional gas chromatography, configured with parallel dual-channel, double detectors, valves switching and back flushing, rapid analysis of the gas compositions consisting of C1-C5 hydrocarbons and permanent gases, such as CO2, H2S, H2, and CO, for direct coal liquefaction has been realized. With four packed chromatographic columns, which are Hayesep-Q pre-column, Hayesep-Q column, molecular sieve 5A column and one PLOT A1203 S capillary column, the gas compositions for direct coal liquefaction are analyzed qualitatively and quantitatively by the external standard method. The determination method has such advantages as excellent separation, simple operation, rapid analysis and accurate results. 展开更多
关键词 gas chromatography gas compositions direct coal liquefaction external standard method
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Zircon U-Pb Chronology and Whole-rock Sr-Nd Isotope Compositions of Granite Porphyry in the Kaladaban Area of the Northern Altyn
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作者 JIA Wenbin LI Yongsheng +1 位作者 MI Kuifeng YU Xiaofei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第1期200-201,共2页
Objective The Altyn Tagh marks the northern margin of the Qinghai-Tibet Plateau and lies between the Tarim block to the north and the Qaidam block,Qilian Orogen,and Kunlun orogenic belt to the south.The Altyn Tagh reg... Objective The Altyn Tagh marks the northern margin of the Qinghai-Tibet Plateau and lies between the Tarim block to the north and the Qaidam block,Qilian Orogen,and Kunlun orogenic belt to the south.The Altyn Tagh region contains ophiolite,high-to ultrahigh-pressure metamorphic rocks,and igneous rocks.Previous research has virified the occurrence of continental rifting,subduction,slab roll-back,and collision between the Tarim block and Proto-Tethys oceanic plate.Moreover,Kaladaban volcanic rocks are mainly distributed in the north Altyn region.Studies of the magmatic evolution of this region have proposed that Altyn oceanic plate was subducted during the Ordovician(Han et al.,2012;Wang et al.,2017).However,the specific timing and other aspects of the subduction are debated,and an investigation of granite porphyry in the Kaladaban area would improve our understanding of this subduction event.In this study,we present new U-Pb zircon dating result and Sr-Nd isotope composition data for granite porphyry from the North Altyn region.The objective is to constrain the timing of subduction of the North Altyn oceanic plate and establish the petrogenesis and magma source of the granite porphyry. 展开更多
关键词 ZIRCON U-PB CHRONOLOGY and Whole-rock SR-ND Isotope compositions of Granite PORPHYRY in the Kaladaban Area of the NORTHERN Altyn NORTHERN
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Compositions and possible sources of lunar meteorite NWA 4884
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作者 CHEN Jian LING Zongcheng +6 位作者 LI Bo SUN Lingzhi ZHANG Jiang HUANG Yihang WU Zhongchen NI Yuheng LIU Jianzhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期269-270,共2页
1 Introduction Lunar mare basalts represent the products of partial remelting of deep mantle sources and provide windows into the compositions of lunar interior.Nine Apollo andLuna missions returned large amounts of m... 1 Introduction Lunar mare basalts represent the products of partial remelting of deep mantle sources and provide windows into the compositions of lunar interior.Nine Apollo andLuna missions returned large amounts of mare basaltic samples,while remote sensing suggests that sampled basalts may cover only a small number of the lunar basalt 展开更多
关键词 TH CA compositions and possible sources of lunar meteorite NWA 4884 GRS
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