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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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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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Rare-earth and trace elements and hydrogen and oxygen isotopic compositions of Cretaceous kaolinitic sediments from the Lower Benue Trough, Nigeria: provenance and paleoclimatic significance 被引量:2
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作者 Anthony T.Bolarinwa Sunday O.Idakwo David L.Bish 《Acta Geochimica》 EI CAS CSCD 2019年第3期350-363,共14页
This study evaluated the Cretaceous(Campanian–Maastrichtian) kaolinitic sediments of the Ajali/Mamu and Enugu/Nkporo Formations from the Lower Benue Trough of Nigeria. A combined method of inductively coupled plasma... This study evaluated the Cretaceous(Campanian–Maastrichtian) kaolinitic sediments of the Ajali/Mamu and Enugu/Nkporo Formations from the Lower Benue Trough of Nigeria. A combined method of inductively coupled plasma–mass spectrometry and isotope ratio mass spectrometry was used to investigate trace and rareearth element geochemistry and hydrogen and oxygen isotopic compositions. These data were then used to infer the sediments' provenance and paleoclimatic conditions during their deposition. The sediments contained low concentrations of most trace elements, with the exceptions of Zr(651–1352 ppm), Ba(56–157 ppm), V(38–90 ppm),and Sr(15.1–59.6 ppm). Average values of Co and Ni were1.5 and 0.7 ppm, respectively. Trace and rare earth element values were lower than corresponding values for upper continental crust and Post-Archean Australian Shale, with the exception of Zr. The samples showed only slight light rare-earth enrichment and nearly flat heavy rare-earth depletion patterns, with negative Eu and Tm anomalies,typical of felsic sources. Geochemical parameters such as La/Sc, Th/Sc, and Th/Co ratios support that the kaolinitic sediments were derived from a felsic rock source, likely deposited in an oxic environment.^(18 )O values ranged from+ 15.4 to + 21.2% for the investigated samples, consistent with a residual material derived from chemicalweathering of felsic rock and redeposited in a sedimentary basin(typical values of + 19 to + 21.2%). While in the basin, the sediments experienced extended interactions with meteoric water enriched in d D and d16 O. However,the variation in d D and d16 O values for the investigated samples is attributed to the high temperature of formation(54–91 °C). The d D and d^(18 )O values suggest that the sediments, although obtained from different localities within the Lower Benue Trough, formed under similar hot,tropical climatic conditions. 展开更多
关键词 RARE-EARTH and trace elements Oxygen/ hydrogen isotopic composition Kaolinitic SEDIMENTS LOWER Benue TROUGH NIGERIA
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Attribution of the Langshan Tectonic Belt: Evidence from zircon U-Pb ages and Hf isotope compositions 被引量:5
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作者 Chuang Bao Yuelong Chen +1 位作者 Xiangkun Zhu Junxiang Zhao 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第2期539-551,共13页
This study describes a previously unidentified Neoproterozoic mafic dyke emplaced in the northern flank of the Langshan Tectonic Belt. This dyke intruded into the micaquartz schist of the Zhaertaishan Group, and yield... This study describes a previously unidentified Neoproterozoic mafic dyke emplaced in the northern flank of the Langshan Tectonic Belt. This dyke intruded into the micaquartz schist of the Zhaertaishan Group, and yielded an age of 908 ± 8 Ma. The youngest U-Pb ages of micaquartz schist from the Zhaertaishan Group in the Langshan area were 1118 ± 33 Ma,1187 ± 3 Ma and 1189 ± 39 Ma,suggesting that the depositional age of the protolith of the schist was between 908 ± 8 Ma and 1118 ± 33 Ma. In addition, 436 U-Pb age data and 155 Lu-Hf isotopic data from six samples in the Langshan Tectonic Belt and one Permian greywacke from the Wuhai area show distinct differences between the northern and southern flanks of the Main Langshan area. The U-Pb ages of the northern flank are primarily Meso-Neoproterozoic; similar ages have not been identified in the southern flank to date.Moreover, two-stage Hf model ages of the northern flank feature three age peaks at ~900 Ma,~1700 Ma and ~2600 Ma; this differs from Hf model ages of the southern flank, which feature one strong age peak at ~2700 Ma. These results suggest that the northern and southern flanks of the Main Langshan area have different geochronologic characteristics and should be divided further. Based on the U-Pb ages and Hf model ages, the northern and southern flanks of the Main Langshan area are named the North and South Langshan Tectonic Belts. Comparison of the U-Pb age and two-stage Hf model age distributions from the North Langshan Tectonic Belt, South Langshan Tectonic Belt, Alxa Block and the North China Craton(NCC) reveal that the North Langshan Tectonic Belt is similar to the Alxa Block and that the South Langshan Tectonic Belt is similar to the NCC. In addition, the zircon U-Pb age of 860 ±7 Ma commonly observed in the Alxa Block was detected in the Permian greywacke from the Wuhai area of the NCC, which suggests that the amalgamation of the North and South Langshan Tectonic belts(i.e.,the amalgamation of the Alxa Block and the NCC), occurred between Devonian and late Permian. 展开更多
关键词 Langshan TECTONIC BELT ATTRIBUTION Alxa Block North China CRATON U-PB Hf ISOTOPIC composition
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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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Chemical Compositions of the Leaf Essential Oils of <i>Aralia spinosa</i>from Three Habitats in Northern Alabama
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作者 Purva C. Davé Bernhard Vogler William N. Setzer 《American Journal of Plant Sciences》 2011年第3期507-510,共4页
Aralia spinosa leaves were collected from three different habitats in north Alabama. The leaf essential oils were collected by hydrodistillation and analyzed by gas chromatography / mass spectrometry (GC-MS). The most... Aralia spinosa leaves were collected from three different habitats in north Alabama. The leaf essential oils were collected by hydrodistillation and analyzed by gas chromatography / mass spectrometry (GC-MS). The most abundant components of A. spinosa essential oils were the sesquiterpenes germacrene D (28.0% - 37.3%), (E)-caryophyllene (8.2% - 15.7%), and α-humulene (1.9% - 4.9%);the monoterpene myrcene (up to 15.1%), and the fatty-acid-derivative (2E)-hexenal (trace to 28.9%). Fatty-acid derivatives and monoterpene hydrocarbons were more abundant in samples from suburban Huntsville than those from “natural” habitats (Monte Sano Mountain, Wheeler National Wildlife Refuge), while sesquiterpene hydrocarbons were more abundant in the natural/wild samples. 展开更多
关键词 ARALIA spinosa ARALIACEAE LEAF Essential Oil Chemical Composition Germacrene D MYRCENE (E)-Caryophyllene (2E)-Hexenal
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Microbial Compositions and Enzymes of a Forest Ecosystem in Alabama: Initial Response to Thinning and Burning Management Selections
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作者 Fritz A. Ntoko Terrence G. Gardner +1 位作者 Zachary N. Senwo Veronica Acosta-Martinez 《Open Journal of Forestry》 2018年第3期328-343,共16页
Prescribed burning and tree thinning are commonly used restoration practices for US forests management to increase forest productivity and enhance plant and animal diversity. The impact of these practices in Alabama’... Prescribed burning and tree thinning are commonly used restoration practices for US forests management to increase forest productivity and enhance plant and animal diversity. The impact of these practices in Alabama’s Bankhead National Forest (BNF) to soil microbial components and overall forest soil health are unknown. We hypothesized that microbial assemblages and enzyme activities are continuously changing in forest ecosystems especially due to management selections. Therefore, the objective of this study was to assess changes in microbial community compositions (fungal vs bacterial populations) via fatty acid methyl ester (FAME) profiling and several enzyme activities (β-glucosaminidase, acid phosphatase, arylsulfatase, β-glucosidase, xylanase, laccase, and manganese peroxidase) critical to soil organic matter (SOM) dynamics and biogeochemical cycling. In this forest, heavily-thinned plots without burning or less frequent burning treatments seemed to provide more favorable conditions (higher pH and lower C:N ratios) for C and N mineralization. This may explain a slight increase (by 12%) detected in fungi:bacteria (F:B) ratio in the heavily-thinned plots relative to the control. Thinned (lightly and heavily) plots showed greater ligninolytic (laccase and MnP) activities and lower β-glucosidase and β-glucosaminidase activities compared to the no-thinned plots probably due to increase depositions of woody recalcitrant C materials. We observed significant but negative correlations between the ligninolytic laccase and manganese peroxidase (Lac and MnP) enzymes respectively, with MBC (?0.45* and ?0.68** respectively) and MBN (?0.43* and ?0.65** respectively). Prescribed burning treatment reduced microbial biomass C and N of the 9-yr burned plot/lightly thinned plotsprobably due to depletion of labile C sources with the high temperatures, leaving mostly recalcitrant C sources as available soil substrates. Gram-positive bacteria (i15:0, a15:0, i17:0, and a17:0), actinomycetes (10-Me17:0, 10-Me18:0), AMF (16:1ω5c), and saprophytic fungi (18:1ω9c), largely contributed to the microbial compositions. This study bridges knowledge gaps in our understanding of microbial community compositions and enzyme-mediated processes in repeatedly burned and thinned forest ecosystems. 展开更多
关键词 FOREST Soil Health FOREST Ecosystems Microbial compositions Enzyme Metabolisms THINNING and BURNING
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Size Distributions of Atmospheric Aerosol Compositions in Saitama, Japan
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作者 Ittipol Paw-Armart Kunio Yoshizumi 《Open Journal of Air Pollution》 2013年第1期1-6,共6页
A survey of atmospheric aerosols in a suburban area near Tokyo, Japanwas conducted using an Andersen sampler. Significant amounts of Na+and Cl- collected were considered to be derived from sea salt. The difference bet... A survey of atmospheric aerosols in a suburban area near Tokyo, Japanwas conducted using an Andersen sampler. Significant amounts of Na+and Cl- collected were considered to be derived from sea salt. The difference between the Na+/Cl-ratio in the area and that in sea salt indicated a considerable loss of Cl-. This is assumed to be caused by the formation of NaNO3, which is one of the main nitrate species present. Most of the sulfate in the sample was found to be (NH4)2SO4 in the form of fine particles, which is different from the sulfate derived from sea salt and soil. The size distributions of K and Mg are also discussed in relation to particular sources. 展开更多
关键词 Size Distribution Chemical compositions PARTICULATE MATTER SULFATE NITRATE Saitama JAPAN
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Comparative advantages of chemical compositions of specific edible vegetable oils
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作者 Li Xue Ruinan Yang +4 位作者 Xuefang Wang Fei Ma Li Yu Liangxiao Zhang Peiwu Li 《Oil Crop Science》 CSCD 2023年第1期1-6,共6页
As important supplementary to major edible oils, comparative chemical advantages of minor edible oils decidetheir development and usage. In this study, chemical composition of 13 kinds of specific edible vegetable oil... As important supplementary to major edible oils, comparative chemical advantages of minor edible oils decidetheir development and usage. In this study, chemical composition of 13 kinds of specific edible vegetable oilswere investigated. The comparative advantages of chemical compositions of these edible oils were obtained asfollows: (1) camellia, tiger nut and almond oil were rich in oleic acid, the contents of which accounted for79.43%, 69.16% and 66.26%, respectively;(2) safflower oil contained the highest content of linoleic acid(76.69%), followed by grape seed (66.85%) and walnut oil (57.30%);(3) perilla seed, siritch, peony seed andherbaceous peony seed oil were rich in α-linolenic acid (59.61%, 43.74%, 40.83% and 30.84%, respectively);(4)the total phytosterol contents of these oils ranged from 91.46 mg/100 g (camellia oil) to 506.46 mg/100 g (siritchoil);and (5) The best source of tocopherols was sacha inchi oil (122.74 mg/100 g), followed by perilla seed oil(55.89 mg/100 g), peony seed oil (53.73 mg/100 g) and herbaceous peony seed oil (47.17 mg/100 g). Thecomparative advantages of these specific edible oils indicated that they possess the high potential nutritionalvalues and health care functions. 展开更多
关键词 Comparative advantages Fatty acid composition Phytosterols Tocopherols Specific vegetable oils Chemical composition
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QSPR modeling of azeotropic temperatures and compositions for binary azeotropes containing lower alcohols using a genetic function approximation 被引量:6
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作者 Yixin Ma Kang Ma +4 位作者 Huixin Wang Xueli Geng Jun Gao Zhaoyou Zhu Yinglong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第4期835-844,共10页
Binary azeotropes, which contain two chemicals with a relative volatility of 1, are very common in the chemical industry. Understanding azeotropes is essential for effectively separating binary azeotropes containing l... Binary azeotropes, which contain two chemicals with a relative volatility of 1, are very common in the chemical industry. Understanding azeotropes is essential for effectively separating binary azeotropes containing lower alcohols. Experimental techniques and ab initio approaches can produce accurate results;however, these two processes are time consuming and labor intensive. Although thermodynamic equations such as UNIFAC are widely used, experimental values are required, and it is difficult to choose the best groups to represent a complex system. Because of their high efficiency and fast calculation speed, quantitative structure–property relationship(QSPR) tools were used in this work to predict the azeotropic temperatures and compositions of binary azeotropes containing lower alcohols. The QSPR models for 64 binary azeotropes based on centroid approximation and weighted-contribution-factor approximation were established using the genetic function approximation(GFA) procedure in Materials Studio software, and a leave-one-out cross-validation procedure was conducted.External tests of an additional 16 azeotropes were also investigated, and high determination coefficient values were obtained. The best QSPR models were explained in terms of the molecular structure of the azeotropes,and good predictive ability was obtained within acceptable prediction error levels. 展开更多
关键词 QSPR AZEOTROPIC temperature AZEOTROPIC composition Genetic function approximation BINARY AZEOTROPES
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耐高温起泡剂膦甲基酚醛树脂PMP的合成及性能 被引量:1
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作者 何耀春 黄步耕 侯士法 《油田化学》 CAS CSCD 北大核心 2004年第4期301-303,306,共4页
由苯酚、甲醛、PCl3合成了水溶性固体膦甲基酚醛树脂(PMP),其HLB值为20 7。简介了合成方法,考察了PMP作为起泡剂的配方性能。PMP溶液室温发泡体积Vf随浓度增大(5~20g/L)而略有增大,泡沫半衰期t1/2在浓度12 5g/L时最长,为20 2min,此时Vf... 由苯酚、甲醛、PCl3合成了水溶性固体膦甲基酚醛树脂(PMP),其HLB值为20 7。简介了合成方法,考察了PMP作为起泡剂的配方性能。PMP溶液室温发泡体积Vf随浓度增大(5~20g/L)而略有增大,泡沫半衰期t1/2在浓度12 5g/L时最长,为20 2min,此时Vf=520mL(/100mL溶液)。在该浓度PMP溶液中分别加入CMC、硅酸钠、三乙醇胺、膨润土使Vf值略降,t1/2值在适宜加量范围大幅延长,加量分别为1 0、2 0、12 5、40g/L时有最大值370 0、85 2、180 2、174 2min;这4个复配PMP/添加剂溶液在温度升高时(30~90℃)Vf值增大但t1/2值大幅缩短。12 5g/LPMP溶液在150~200℃滚动16h后室温下Vf值不变,t1/2值随滚动温度升高而降低,200℃时为11 3min;12 5/2 0/10/40g/LPMP/硅酸钠/三乙醇胺/膨润土溶液在200℃滚动16h后,室温下Vf值为470mL,t1/2值高达50h。PMP为耐高温性能良好的起泡剂,可与硅酸钠、三乙醇胺、膨润土复配使用。图2表4参10。 展开更多
关键词 PMP 2.5g PCl3 HLB 40g f 20g CMC
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Elemental Compositions and Chemical Mass Closure of Fine Particulate in an Animal Feeding Operation Facility and Its Vicinity
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作者 Qian-Feng Li Lingjuan Wang-Li +1 位作者 R. K. M. Jayanty Sanjay Shah 《Journal of Environmental Protection》 2015年第5期409-425,共17页
Particulate matter (PM) emissions from animal feeding operations (AFOs) have been considered as an important contributor to ambient PM in rural areas. Investigation of the chemical compositions of PM2.5 inside and in ... Particulate matter (PM) emissions from animal feeding operations (AFOs) have been considered as an important contributor to ambient PM in rural areas. Investigation of the chemical compositions of PM2.5 inside and in the vicinity of AFOs can enhance our understanding of the AFO emissions impact on ambient PM characteristics. This year-long field study was conducted on a commercial egg production farm to investigate ambient PM chemical compositions as impacted by the air emissions from the production houses. The PM2.5 samples were collected from five sampling stations (one in-house station and four ambient locations in four wind directions). The trace elements, major ions, organic carbon (OC) and element carbon (EC) were analyzed by X-ray florescence (XRF), ion chromatography (IC), and thermo-optical analyzer, respectively. There were significant differences in elemental compositions between PM samples from in-house station (ST1) and ambient stations (ST2-ST5). The chemical mass balance analysis revealed that OC accounted for above 50% of PM2.5 mass at in-house and ambient stations;NH4+, SO42-, and NO3- accounted for about 40.0% of the total PM2.5 mass in ambient locations and for only 12% of the total PM2.5 mass in house. The measured PM2.5 masses agreed with the sums of the masses of chemical compositions at all stations except for the in-house station. Knowledge gained from this study, with additional consideration of NH3 concentrations and emissions, will lead to better understanding of PM2.5 source and formation, fate and transport, and their atmospheric dynamics. 展开更多
关键词 Animal Feeding Operations PM2.5 CHEMICAL SPECIATION ELEMENTAL Composition MASS Balance
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Structures and Properties of Iron Matrix Composites with Tungsten Carbide Particle by EPC-V Process 被引量:5
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作者 Xu Daqing Luo Jirong Huang Naiyu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1999年第2期29-32,共4页
In this paper the Expendable Pattern Casting with dry sand Vacuum(EPC-V) process is used to manufacture iron matrix composites with tungsten carbide particle.Microstructures of the composites layers were analyzed.The ... In this paper the Expendable Pattern Casting with dry sand Vacuum(EPC-V) process is used to manufacture iron matrix composites with tungsten carbide particle.Microstructures of the composites layers were analyzed.The abrasive wear resistance of the composites layers were tested and compared with that of high chromium cast iron.The results show that the iron matrix composites with tungsten carbide particle have high hardness.The abrasive wear resistance of composites with tungsten carbide particle is higher than that of high chromium cast iron.The properties of the matrix materials have been improved remarkably. 展开更多
关键词 ABSTRACT:In this paper the Expendable Pattern Casting with dry sand Vacuum (EPC V) PROCESS is used to manufacture iron matrix COMPOSITES with TUNGSTEN CARBIDE particle. Microstructures of the COMPOSITES layers were analyzed. The ABRASIVE wear
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雷琼地区晚新生代玄武岩地球化学:EM2成分来源及大陆岩石圈地幔的贡献 被引量:24
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作者 韩江伟 熊小林 朱照宇 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3208-3220,共13页
对雷琼地区21个晚新生代玄武岩样品的主量、微量元素和Sr、Nd、Pb同位素分别用湿化学法、ICP-MS和MC-ICPMS进行了测定。这些玄武岩主要为石英拉斑玄武岩,其次为橄榄拉斑玄武岩和碱性玄武岩。大多数样品的微量元素和同位素成分与洋岛玄武... 对雷琼地区21个晚新生代玄武岩样品的主量、微量元素和Sr、Nd、Pb同位素分别用湿化学法、ICP-MS和MC-ICPMS进行了测定。这些玄武岩主要为石英拉斑玄武岩,其次为橄榄拉斑玄武岩和碱性玄武岩。大多数样品的微量元素和同位素成分与洋岛玄武岩(OIBs)相似,而且随着SiO_2不饱和度增加,不相容元素含量也增加。除R4-1可能受到地壳混染外,其他样品相对均一的Nd同位素(ε_(Nd)=2.5~6.0)以及变化明显但范围有限的Sr同位素(0.703106~0.704481),可能继承了地幔源区的特征。^(87)Sr/^(86)Sr与^(206)Pb/^(204)Pb的正相关和^(143)Nd/^(144)Nd与^(206)Pb/^(204)Pb的负相关特征暗示DM(软流圈地幔)与EM2(岩石圈地幔)的混合。地幔捕虏体的同位素特征暗示EM2成分不可能存在于尖晶石橄榄岩地幔,而La/Yb和Sm/Yb系统表明岩浆由石榴石橄榄岩部分熔融产生,这意味着EM2成分可能存在于石榴石橄榄岩地幔。雷琼地区玄武岩的地球化学变化可以用软流圈地幔为主的熔体加入不同比例石榴石橄榄岩地幔不同程度熔融产生的熔体来解释:碱性玄武岩和橄榄拉斑玄武岩是软流圈熔体与石榴石橄榄岩地幔较低程度(7%~9%)熔融体混合,而石英拉斑玄武岩是软流圈熔体与石榴石橄榄岩地幔较高程度(10%~20%)熔融体的混合。 展开更多
关键词 area asthenospheric MANTLE garnet peridotite negative correlation isotopic composition wet chemical method MANTLE xenoliths trace elements
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Resource Potentials of Composting the Organic Wastes Stream from Municipal Solid Wastes Compositions Arising in Nigerian Cities
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作者 Adamu Isa Harir Rozilah Kasim Bala Ishiyaku 《Journal of Geoscience and Environment Protection》 2015年第4期10-15,共6页
The paper presented an assessment of the resource potentials of composting organic waste materials arising from the municipal solid waste stream from cities in Nigeria. Through a review of quantitative data, the compo... The paper presented an assessment of the resource potentials of composting organic waste materials arising from the municipal solid waste stream from cities in Nigeria. Through a review of quantitative data, the composition of municipal solid waste arising within cities in Nigeria was examined in order to identify the potentials for composting organic materials from the waste stream composition. The data showed that the average majority of the waste stream was organic materials which implied high potentials for composting organic waste materials from Nigerian cities. The review also identified further potentials for composting was associated with the large population and the majority of them engaged in agriculture, as a high potential market for compost manure in Nigeria. There were more potentials derivable from the current policies of importing and supplying chemical fertilizer with huge subsidies for domestic agriculture in the country. The need to substitute these policies of chemical fertilizer with the use of compost manure implied high potentials for composting in the country. The paper also identified numerous benefits of composting in general and with particular reference to the Nigerian situation which includes, among others a reduction of the vast quantity of solid waste for final disposal, reducing air pollution and ground water leachate and also employment generation and increased income. Therefore, the paper recommended a deliberate government policy to promote composting of organic solid wastes material and marketing of compost manure to substitute the current policies of importing chemical fertilizer with subsidy for domestic agriculture as a strategy to achieve sustainable waste management in Nigeria. 展开更多
关键词 COMPOSTING Organic WASTES WASTE Composition Sustainable WASTE Management Resource POTENTIALS
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Determination of potassium content as principal components in pyrotechnic compositions used for fireworks and firecrackers based on inductively coupled plasma optical emission spectrometric approach (ICP-OES)
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作者 Xiao Huan-xin Wu Jun-yi 《International Journal of Technology Management》 2014年第2期87-90,共4页
Inductively coupled plasma optical emission spectrometric approach(1CP-OES) is used to determine the potassium content as principal component in pyrotechnic compositions used for fireworks and firecrackers. Element ... Inductively coupled plasma optical emission spectrometric approach(1CP-OES) is used to determine the potassium content as principal component in pyrotechnic compositions used for fireworks and firecrackers. Element of potassium is conunonly found in potassium nitrate and potassium perchlorate in pyrotechnic compositions in fireworks and firecrackers. Statistical analysis shows that potassium nitrate content in pyrotechnics is between 10% to 60% and the potassium perchlorate content is between 20% to 70%,which counted in the content of potassium element is between 4% to 23%. Concept of this method: considering the weight of the sample is 400rag,constant volume is 1L and the concentration of potassium is between 10 mg/L to 90 mg/L in sample solution, the determination scope of the method for the potassium content would be between 1% to 23%.Further experiments proved that the fitting correlation coefficient of potassium calibration curve is 0.9997 or higher, recovery is 89.15%-100.23%.The allowable differential value is 0.4% between two single tests under repeatable conditions. This method can completely satisfy the requirements of the fireworks and firecrackers industry with high accuracy and good precision. 展开更多
关键词 fireworks and firecrackers pyrotechnic compositions principal component POTASSIUM content DETERMINATION inductively coupled plasma optical emission spectrometric approach ICP-OES.
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The biomedical significance of the phytochemical, proximate and mineral compositions of the leaf, stem bark and root of Jatropha curcas 被引量:2
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作者 Atamgba Agbor Asuk Margaret Akpana Agiang +1 位作者 Kayode Dasofunjo Amonor James Willie 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第8期635-641,共7页
Objective: To analyse the phytochemical contents of leaf, stem bark and root of Jatropha curcas(J. curcas) in four solvent extracts and their proximate and mineral compositions. Methods: Standard analytical procedures... Objective: To analyse the phytochemical contents of leaf, stem bark and root of Jatropha curcas(J. curcas) in four solvent extracts and their proximate and mineral compositions. Methods: Standard analytical procedures were used for the determination of phytochemicals, proximate and mineral compositions of the leaf, stem bark and root extracts of J. curcas. Results: Results of the analysis showed the presence of polyphenols, flavonoids, alkaloids, cardiac glycosides, coumarins, saponins, terpenoids, steroids, triterpenoid saponins, carotenoids, phlobatannins and tannins in the leaf, stem bark and root of all the solvent extracts. Flavonoids were present in the highest amount in the ethyl acetate extracts of the leaf(7.35% ± 0.02%), stem bark(4.12% ± 0.01%) and root(3.35% ± 0.02%) followed by polyphenols in the methanol extracts of leaf(4.62% ± 0.02%), stem bark(2.77% ± 0.05%) and root(2.49% ± 0.02%). Poly-acetylated compounds were absent in all the solvent extracts of the leaf, stem bark and root. However, some anti-nutritional agents such as oxalates, phytates and cyanates were present in all the solvent extracts of the leaf, stem bark and root except the ethyl acetate. Phytates were high in the aqueous solvent of the leaf(6.12% ± 0.00%) but low in the stem bark(1.00% ± 0.05%) and root(0.89% ± 0.03%). Proximate composition showed appreciable amounts of total carbohydrate(36.33% ± 0.72%), crude protein(26.00% ± 0.47%) and reducing sugars(5.87% ± 0.14%) in the leaf, while crude fat was more in the stem bark(16.70% ± 0.30%). There was corresponding substantial energy in the leaf [(1 514.77 ± 20.87) kJ /100 g] and stem bark [(907.00 ± 8.52) kJ /100 g]. Moisture and ash contents of the leaf, stem bark and root were within acceptable limits for the use in drugs formulation. The mineral composition showed substantial amounts of important elements such as Fe, Ca, Na, Mg and Zn. Others were P, K and Se. Conclusions: The outcome of this study suggests that the leaf, stem bark and root of J. curcas have very good medicinal potentials, meet the standard requirements for drug formulation and serve as good sources of energy and nutrients except for the presence of some anti-nutritional elements predominant in the leaf. 展开更多
关键词 JATROPHA curcas Solvent extracts PHYTOCHEMICALS PROXIMATE COMPOSITION Mineral COMPOSITION
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Determination of magnesium and aluminum content as principal components in pyrotechnic compositions used for fireworks and firecrackers based on inductively coupled plasma optical emission spectrometric approach (ICP-OES)
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作者 Wu Jun-yi Xiao Huan-xin 《International Journal of Technology Management》 2014年第1期82-86,共5页
Inductively coupled plasma optical emission spectrometric approach(ICP-OES)is used to determine the magnesium and aluminum content as principal components in pyrotechnic compositions used for fireworks and firecrack... Inductively coupled plasma optical emission spectrometric approach(ICP-OES)is used to determine the magnesium and aluminum content as principal components in pyrotechnic compositions used for fireworks and firecrackers. Elements of magnesium and aluminum are commonly found in aluminum powder or magnesium-aluminum alloy powder in pyrotechnic compositions in fireworks and firecrackers. Statistical analysis shows that the magnesium content in pyrotechnics is between 8% to 30% and the aluminum content is between 8% to 35%(roughly).Concept of this method: suppose the weight of the sample is 400rag,constant volume is IL and the concentlation of magnesium and aluminum is between 12mg/L to 160mg/L in sample solution, the determination scope of the method for magnesium and aluminum content would be between 3% to 40%.Further experiments proved that the fitting correlation coefficient of the magnesium calibration curve is 0.9999 or higher, recovery is 101.01% -101.96%.The fitting correlation coefficient of the aluminum calibration curve is 0.9999 or higher, recovery is 99.36%-103.07%. The allowable differential value is 0.4% between two single tests under repeatable conditions. This method can completely satisfy the requirements of the fireworks and firecrackers industry with high accuracy and good precision. 展开更多
关键词 fireworks and firecrackerspyrotechnic compositions principal components MAGNESIUM ALUMINUM CONTENT determination induct ively coupled plasma optical emission spectrometric approach ICP-OES.
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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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内蒙古克什克腾旗小东沟斑岩型钼矿床成岩成矿机制探讨 被引量:29
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作者 覃锋 刘建明 +1 位作者 曾庆栋 罗照华 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3357-3368,共12页
本文选取内蒙古克什克腾旗的小东沟斑岩型钼矿区作为研究区,它位于西拉沐伦钼矿带的西南部。对小东沟岩体进行了主微量元素、SHRIMP锆石U-Pb定年等地球化学方面的研究;对岩体中的钾长石和含矿矿物辉钼矿进行了普通铅同位素分析。小东沟... 本文选取内蒙古克什克腾旗的小东沟斑岩型钼矿区作为研究区,它位于西拉沐伦钼矿带的西南部。对小东沟岩体进行了主微量元素、SHRIMP锆石U-Pb定年等地球化学方面的研究;对岩体中的钾长石和含矿矿物辉钼矿进行了普通铅同位素分析。小东沟岩体具有高硅富钾、REE含量低、Zr含量高、无负铕异常、高ε_(Nd)(t)、低Sr_i等特点,指示岩浆起源于加厚新生下地壳的熔融,同时具有高温、快速熔融、快速析离逃离源区的特点;小东沟岩体的SHRIMP锆石U-Pb定年结果为142±2Ma,对应140Ma左右主应力场由南北向转为东西向的构造体制大转折时期,这个时期大兴安岭处于伸展的构造环境下,底侵作用发育,地幔物质可以添加到下地壳熔融形成的岩浆中;对岩体钾长石和辉钼矿进行的普通铅同位素分析显示前者具有从造山带-地幔过渡的特征,后者则显示有地幔特征,说明成岩、成矿物质来自两个不同的源区,下地壳的岩浆和地幔含矿流体发生了混合。通过以上的分析,结合水-岩浆物理反应的实验结果,本文提出小东沟斑岩型钼矿床的成矿模式:大兴安岭地区在早白垩世伸展的构造背景下,地幔含矿流体加入受底侵作用加热的下地壳中使之熔融形成岩浆,随后更多的地幔含矿流体进入岩浆房,促使其迅速析离逃逸出源区,二者一起上升侵位。在岩浆温度较高时,地幔含矿流体和岩浆大致以较稳定的液态不混溶的状态共存;当岩浆和流体侵位到较浅深度时,压力下降,温度降低,晶体增多,流体-岩浆体系变得不稳定,岩浆被流体分割成许多很小的岩浆团。流体中H^+、K^+和各种成矿元素的存在使之必然会和岩浆或冷却后形成的岩石发生蚀变反应,并晶出成矿矿物,形成现在我们看到的具有浸染状矿化现象的小东沟斑岩型钼矿床。 展开更多
关键词 lower CRUST mantle fluid materials isotopic composition tectonic transition SHRIMP METALLOGENIC belt
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