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Protective Effect and Mechanism of n-butanol Extract from Diploclisia glaucescens(B1.)Diels on Rats with Adjuvant Arthritis
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作者 Chuhui ZHOU Zhouyan HUANG +4 位作者 Fengxian ZHAO Yong CHEN Xianxian LIU Xiaolian LIANG Wenli LI 《Medicinal Plant》 CAS 2023年第5期45-48,共4页
[Objectives]To study the protective effect and mechanism of n-butanol extract of Diploclisia glaucescens(B1.)Diels on rats with adjuvant arthritis.[Methods]A rat adjuvant arthritis(AA)model with similarities to a clin... [Objectives]To study the protective effect and mechanism of n-butanol extract of Diploclisia glaucescens(B1.)Diels on rats with adjuvant arthritis.[Methods]A rat adjuvant arthritis(AA)model with similarities to a clinical RA(rheumatoid arthritis)patient was used,and the model was made by injection of Complete Freund s adjuvant(CFA).Body mass and joint swelling degree were used as indicators,and the organ index was calculated and the synovial tissue of rats was examined under microscope to evaluate the protective effect of n-butanol extract on arthritis.The effects of n-butanol extract on TNF-α,IL-1βand PGE_(2)contents in rat serum were detected by ELISA kit.[Results]Arthritic rats experienced significant weight loss;the n-butanol extract reduced the joint swelling in rats.It exerted an effect on rat organs and reduced the contents of TNF-α,IL-1βand PGE_(2) in rat serum,and also reduced synovial inflammation in rats.[Conclusions]The n-butanol extract of D.glaucescens can protect rats with adjuvant arthritis by reducing the content of inflammatory factors. 展开更多
关键词 Diploclisia glaucescens(B1.)Diels n-butanol extract Rats with adjuvant arthritis
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Fractional Envelope Analysis for Rolling Element Bearing Weak Fault Feature Extraction 被引量:6
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作者 Jianhong Wang Liyan Qiao +1 位作者 Yongqiang Ye YangQuan Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第2期353-360,共8页
The bearing weak fault feature extraction is crucial to mechanical fault diagnosis and machine condition monitoring.Envelope analysis based on Hilbert transform has been widely used in bearing fault feature extraction... The bearing weak fault feature extraction is crucial to mechanical fault diagnosis and machine condition monitoring.Envelope analysis based on Hilbert transform has been widely used in bearing fault feature extraction. A generalization of the Hilbert transform, the fractional Hilbert transform is defined in the frequency domain, it is based upon the modification of spatial filter with a fractional parameter, and it can be used to construct a new kind of fractional analytic signal. By performing spectrum analysis on the fractional envelope signal, the fractional envelope spectrum can be obtained. When weak faults occur in a bearing, some of the characteristic frequencies will clearly appear in the fractional envelope spectrum. These characteristic frequencies can be used for bearing weak fault feature extraction.The effectiveness of the proposed method is verified through simulation signal and experiment data. 展开更多
关键词 fractional analytic signal fractional envelope analysis fractional Hilbert transform rolling element bearing weak fault feature extraction
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Antitrypanosomal potentials of the extract and fractions of Abrus precatorius seeds 被引量:2
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作者 Nwodo NJ Nwodo OFC 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第11期857-861,共5页
Objective:To evaluate the in vivo trypanocidal activity of the methanol extract and fractions of Abrus precatorius seeds in mice.Methods:Parasiteamia was induced unto mice by intraperitoneal injection of 1.25×10&... Objective:To evaluate the in vivo trypanocidal activity of the methanol extract and fractions of Abrus precatorius seeds in mice.Methods:Parasiteamia was induced unto mice by intraperitoneal injection of 1.25×10<sup>5</sup> Trypanosoma in normal saline.Five days when a high level of parasiteamia was established treatment commenced until ten days.The mice were treated with 10,20 and 40 mg/kg bt.of the extract and 5 and 10 mg/kg bt.of the fraction(F<sub>2</sub>),respectively for 5 days.Diminazene acelurate at the dose of 3.5 mg/kg bt.for two days was used as the reference drug.The level of parasitaemia and packed cell volume(PCV) of the animals estimated. Results:At doses of 10,20 and 40 mg/kg the crude extract showed a sharp reduction in the level of parasitaemia in mice compared with the untreated group.The mice treated with F,at doses of 5 and 10 mg/kg showed a sharp reduction in the level of parasitamia to zero in day 9,and a gradual recovery from the 12th day of treatment.This effect is comparable to that of the mice treated with 7 mg/kg of standard drug diminazene aceturate.The PCV of the treated showed a gradual decrease with time,but not as much as the untreated group.Phytochemical screening revealed the presence of glycosides,alkaloids,carbohydrates,tannins and proteins in the Abrus precatorius powder while F<sub>2</sub> was rich in alkaloids.Conclusions:This study shows that both the extract and the fractions of Abrus precatorius seeds exhibited a promising trypanocidal property.Alkaloids may be responsible for the observed activity. 展开更多
关键词 Abrus precatorius Seed extract Trypanocidal effect Parasiteamia fractionS TRYPANOSOME BRUCEI BRUCEI Berenil
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Larvicidal efficacy of crude and fractionated extracts of Dracaena loureiri Gagnep against Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and Anopheles minimus mosquito vectors 被引量:2
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作者 Damrongpan Thongwat Ratchanaporn Chokchaisiri +1 位作者 Lucksagoon Ganranoo Nophawan Bunchu 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2018年第5期273-278,共6页
Objective:To evaluate the larvicidal efficacy of crude and fractionated extracts of Dracaena loureiri endocarp against Aedes aegypti,Aedes albopictus,Culex quinquefasciatus,and Anopheles minimus mosquitos.Methods:Larv... Objective:To evaluate the larvicidal efficacy of crude and fractionated extracts of Dracaena loureiri endocarp against Aedes aegypti,Aedes albopictus,Culex quinquefasciatus,and Anopheles minimus mosquitos.Methods:Larvicidal activity was tested according to World Health Organization standard protocol.The third-stage larvae of each mosquito species were exposed to various concentrations of Dracaena loureiri crude extract and six groups of Dracaena loureiri fractionated extracts(RC-DT 009-014).Larval mortality rates were observed after 24 h and48 h of exposure.Then,a computerized probit analysis of the mortality data was performed to determine lethal concentration 50(LC_(50))and lethal concentration 90 values.Results:Anopheles minimus larvae(24-h LC_(50)77.88 mg/L)had the highest susceptibility to crude extract,whereas others(Aedes aegypti,24-h LC_(50)224.73 mg/L;Aedes albopictus,24-h LC_(50)261.75 mg/L;and Culex quinquefasciatus,24-h LC_(50)282.86 mg/L)were significantly less susceptible.The most effective groups of fractionated extracts were RC-DT 012 and RC-DT 013.The mosquito species most susceptible to fractionated extracts was Culex quinquefasciatus,with 24-h LC_(50)values of 0.66 and 0.94 mg/L for RC-DT 012 and RC-DT 013,respectively.Conclusions:The larvicidal activity of fractionated extracts is more effective than that of crude extract against all tested mosquito species.For the most effective alternative larvicide,purification and a phytochemical constituent analysis must be performed. 展开更多
关键词 Dracaena loureiri Aedes aegypti Aedes albopictus Culex quinquefasciatus Anopheles minimus fractionated extract Crude extract LARVICIDAL Mosquito larva
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Changes in Soil Hot-Water Extractable C,N and P Fractions During Vegetative Restoration in Zhifanggou Watershed on the Loess Plateau 被引量:2
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作者 UE Sha LI Peng +2 位作者 LIU Guo-bin LI Zhan-bin ZHANG Chao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2250-2259,共10页
The study was conducted in Zhifanggou Watershed,Shaanxi Province,China,to evaluate the effect of different vegetation types on hot-water extractable C,N and P fractions,with the aim to determine whether hot-water extr... The study was conducted in Zhifanggou Watershed,Shaanxi Province,China,to evaluate the effect of different vegetation types on hot-water extractable C,N and P fractions,with the aim to determine whether hot-water extractable fractions could be used as indicators of soil quality change in Loess Plateau.The six vegetation types established in 1975 were(i) Robinia pseudoacacia L.,(ii) Caragana korshinkii Kom.,(iii) Pinus tabulaeformis Carr.,(iv) P.tabulaeformis-Amorpha fruticosa L.,(v) R.pseudoacacia-A.fruticosa,and(vi) grassland.A cropped hillslope plot and a Platycladus orientalis L.native forest plot were used as references.The results indicated that the conversion of native forest to cropland resulted in a significant decline in the hot-water extractable C,N and P fractions.Hot-water extractable C,N,and P increased when cultivated land was revegetated,but after 30 years the amount of hot-water extractable C,N,and P in revegetated fields was still much lower compared to native forest.Hot-water extractable fractions increased more under mixed-forest than under pure-forest stands.Furthermore,there was a significant correlation between the hot-water extractable fractions and soil chemical and microbiological properties.The results showed that hot-water extractable fractions could be used as indicators of soil quality change on the Loess Plateau. 展开更多
关键词 soil hot-water extractable fraction vegetative restoration Loess Plateau
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Underlying mechanism of protection from hypoxic injury seen with n-butanol extract of Potentilla anserine L. in hippocampal neurons 被引量:11
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作者 Xiaojing Qin Lingzhi Li +4 位作者 Qi Lv Baoguo Yu ShuwangYang Tao He Yongliang Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第33期2576-2582,共7页
The alcohol and n-butanol extract of Potentilla anserine L. significantly protects myocardium from acute ischemic injury. However, its effects on rat hippocampal neurons and the mechanism of protection remain unclear.... The alcohol and n-butanol extract of Potentilla anserine L. significantly protects myocardium from acute ischemic injury. However, its effects on rat hippocampal neurons and the mechanism of protection remain unclear. In this study, primary cultured hippocampal neurons from neonatal rats were incubated in 95% N2 and 5% CO2 for 4 hours. Results indicated that hypoxic injury decreased the viability of neurons, increased the expression levels of caspase-9 and caspase-3 mRNA, as well as cytochrome c, Caspase-9, and Caspase-3 protein. Pretreatment with 0.25, 0.062 5, 0.015 6 mg/mL n-butanol extract of Potentilla anserine L. led to a significant increase in cell viability. Expression levels of caspase-9 and caspase-3 mRNA, as well as cytochrome c, Caspase-9, and Caspase-3 protein, were attenuated. The neuroprotective effect of n-butanol extract of Potentilla anserine L. was equivalent to tanshinone IIA. Our data suggest that the n-butanol extract of Potentilla anserine L. could protect primary hippocampal neurons from hypoxic injury by deactivating mitochondrial cell death. 展开更多
关键词 n-butanol extract of Potentilla anserine L. neuron hypoxia mitochondria injury cytochrome c caspase neural regeneration
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Redistribution of Pb, Zn and Cu Fractions in Tailing Soils Treated with Different Extractants 被引量:12
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作者 LIU Yun-Guo WANG Xian-Hai +5 位作者 ZENG Guang-Ming LI Xin ZHOU Chun-Hua FAN Ting LI Yong-Li YUAN Xin-Zhong 《Pedosphere》 SCIE CAS CSCD 2006年第3期312-318,共7页
The efficiency of EDTA, HNO3 and CaCl2 as extractants to remove Pb, Zn and Cu from tailing soils without varying soil pH was investigated with distributions of Pb, Zn and Cu being determined before and after extractio... The efficiency of EDTA, HNO3 and CaCl2 as extractants to remove Pb, Zn and Cu from tailing soils without varying soil pH was investigated with distributions of Pb, Zn and Cu being determined before and after extraction using the sequential extraction procedure of the optimized European Community Bureau of Reference (BCR). Results indicated that EDTA and HNO3 were both effective extracting agents.The extractability of extractants for Pb and Zn was in the order EDTA > HNO3 > CaCl2, while for Cu it was HNO3 > EDTA > CaCl2. After EDTA extraction, the proportion of Pb, Zn and Cu in the four fractions varied greatly, which was related to the strong extraction and complexation ability. Before and after extraction with HNO3 and CaCl2, the percentages of Pb, Zn and Cu in the reducible, oxidizable and residual fractions changed little compared to the acid-extractable fraction. The lability of metal in the soil and the kinds of extractants were the factors controlling the effects of metal extraction. 展开更多
关键词 萃取法 重金属 土壤污染 废料
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Extractable Fractions of Metals in Sewage Sludges from Five Typical Urban Wastewater Treatment Plants of China 被引量:8
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作者 WANG Chao LI Xiao-Chen +2 位作者 WANG Pei-Fang ZOU Li-Min MA Hai-Tao 《Pedosphere》 SCIE CAS CSCD 2006年第6期756-761,共6页
Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in Chi... Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR (Community Bureau of Reference) sequential extraction procedure. The sludges contained considerable amounts of organic matter (31.8%-48.0%), total N (16.3-26.4 g kg-1) and total P (15.1-23.9 g kg-1), indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China's control standards for pollutants in sludges from agricultural use (GB 4284-1984). The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples reflected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn. 展开更多
关键词 重金属 污水 生物利用率 废水处理
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GC/MS Analysis of Fractional Extraction of Fusain from Tongting Bituminous Coal in CS_2 被引量:10
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作者 QIN Zhi-hong JIANG Chun SUN Hao ZONG Zhi-min JIANG Bing WEI Xian-yong 《Journal of China University of Mining and Technology》 EI 2006年第1期8-12,共5页
Fusain from Tongting (Huaibei, Anhui Province) bituminous (FTTB) coal was fractionally extracted using Soxhlet extractor with CS2. Then the extracts were analyzed with GC/MS. Comparison of experimental data between FT... Fusain from Tongting (Huaibei, Anhui Province) bituminous (FTTB) coal was fractionally extracted using Soxhlet extractor with CS2. Then the extracts were analyzed with GC/MS. Comparison of experimental data between FTTB coal and clarain from Tongting bituminous (CTTB) coal was carried out. The results show that the kinds of small molecule components detected by GC/MS of FTTB are less than those of CTTB. Long-chain alkanes exist mostly in the extracts of fusain. Macromolecular networks are predominant in the FTTB coal mainly composed of inertinite in the coal petrography. The size of micropores in the FTTB coal is relatively small, and the development of micropores is relatively low. Thus the content of aromatic compounds with affinity for micropores is relative low in FTTB, while the content of long-chain alkanes with affinity for macromolecule networks is relatively high. Sub-components in exinite determine the distribution of long-chain alkanes extracted in the last stage. Odd-numbered carbon distribution appears when resin is most in exinite, while high carbon alkane distribution appears when exinite is dominant in cutinite. Small aromatic molecules are firstly packed in micropores, and exist in a free state after micropores are saturated. 展开更多
关键词 丝炭 煤化学 GC/MS CS2 FTTB
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GC/MS Analysis of Organic Compounds in Hot Water-Extractable Fraction from Shenfu Coal 被引量:7
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作者 LI Bao-min YUAN Cheng ZONG Zhi-min CAO Jing-pei LIU Guang-feng WEI Xian-yong 《Journal of China University of Mining and Technology》 EI 2007年第3期354-357,共4页
Shenfu Coal was extracted with hot pure water and slurry was isolated. The concentrated benzene-soluble fraction (CBSF) was analyzed with GC/MS and four types of organic compounds (OCs) were detected: HACOCs,DTEs,DMDT... Shenfu Coal was extracted with hot pure water and slurry was isolated. The concentrated benzene-soluble fraction (CBSF) was analyzed with GC/MS and four types of organic compounds (OCs) were detected: HACOCs,DTEs,DMDT and LCAs. The amount of benzyl benzoate which is the most abundant OC was calculated by an inter-nal standard method with an indicated amount of BP. The broken hydrogen bonds and ether bonds were responsible for the extraction of OCs from the coal .DTEs,DMDT and LCAs are essentially insoluble in water,whereas they are soluble,probably owing to intermolecular interaction of OCs with HACOCs. 展开更多
关键词 热萃取 GC/MS分析 水溶部分 煤化学
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Study of Constituents of Fractionated Extraction from Datong Coal 被引量:3
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作者 WANG Xiao-hua WEI Xian-yong 《Journal of China University of Mining and Technology》 EI 2005年第4期299-304,共6页
Datong coal was extracted with CS2, H-hexane, benzene, methanol, acetone, tetrahydro-furan(THF) and THF/methanol(l:3,v/v) mixed solvent sequentially. The extracts were analyzed with GC/MS. It is presented that group s... Datong coal was extracted with CS2, H-hexane, benzene, methanol, acetone, tetrahydro-furan(THF) and THF/methanol(l:3,v/v) mixed solvent sequentially. The extracts were analyzed with GC/MS. It is presented that group seperation of soluble organic compounds in the coal can be achieved by fractionated extraction using different solvents. The results show that CS2 was effective for extracting arenes from the coal sample. n-Hexane extractable fraction from Datong coal mainly consists of n-alkanes. A great variety of oxygen-containing compounds are dominant in the components of methanol-soluble fraction. Acyclic isoprenoids, pentecyclic triterpanes and a series of cyclohexanes with long-chain alkyl-substitutes are detected in acetone-soluble fraction. Dicyclic aramatic hydrocarbons are identified in benzene-soluble fraction and 4-6 cyclic condensed aramatic hydrocarbons are identified in THF-soluble fraction. The molecular structures detection of 1,2-dichlorobenzene, 2,4-dibromophnol, 2,4,6-tribromophenol and 4-chlorobenzophe- none firstly provide information for existence form of bromine and chlorine in coal. 展开更多
关键词 煤化学 山西 大同市 分馏工艺 化学成分 可溶解性
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GC/MS analyses of fractionated extraction of Shenfu coal with CS2,n-hexane,benzene 被引量:2
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作者 王晓华 魏贤勇 《Journal of Coal Science & Engineering(China)》 2008年第4期672-674,共3页
Shenfu coal was extracted with 0S2,n-hexane,benzene sequentially.The ex- tracts were analyzed with GC/MS.It is presented that group seperation of soluble organic compounds in the coal can be achieved by fractionated e... Shenfu coal was extracted with 0S2,n-hexane,benzene sequentially.The ex- tracts were analyzed with GC/MS.It is presented that group seperation of soluble organic compounds in the coal can be achieved by fractionated extraction using different solvents. Main components in CS2 soluble fraction from Shenfu coal are alkyl-substituted arenes. Aliphatic hydrocarbons are overwhelmingly predominant in n-hexane-soluble fraction.Di- to tricyclic aramatic hydrocarbons are identified in benzene-soluble fraction.The molecular structures detection of 2,4,6-trichlorobenzenamine and 3,3',4,4',5,5'-hexachloro-1,l'- biphenyl and 2-chlorocyclohexanol firstly provide information for existence form of chlorine in coal. 展开更多
关键词 煤岩 组分 二硫化碳 分析
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Investigation of extraction fraction in confined impinging jet reactors for tri-butyl-phosphate extracting butyric acid process 被引量:1
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作者 Zhengming Gao Manting Zhao +2 位作者 Yun Yu Zhipeng Li Jing Han 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第2期310-316,共7页
The extraction fraction E and overall volumetric mass transfer coefficient kLa of TBP extracting butyric acid process in confined impinging jet reactors(CIJR) with two jets were investigated.The main variables tested ... The extraction fraction E and overall volumetric mass transfer coefficient kLa of TBP extracting butyric acid process in confined impinging jet reactors(CIJR) with two jets were investigated.The main variables tested were the concentration of tri-butyl-phosphate(TBP) and butyric acid,the impinging velocity V,the impinging velocity ratio of two phases Vorg/Vaq,the nozzle inner diameter diand the distance L between the jet axes and the top wall of the impinging chamber.The results showed that E and kLa increase with an increase of the impinging velocity V,the concentration of TBP Corg,and the impinging velocity ratio Vorg/Vaq.However,E and kLa decrease with an increase of the inner diameter difrom 1 to 2 mm,the concentration of butyric acid Caqfrom 0.5%(v/v) to2%(v/v).The factor L ranging from 3 to 11 mm has a negligible effect on E and kLa.A correlation on these variables and kLa was proposed based on the experimental data.These results indicated good mass transfer performance of CIJR in the extraction operation. 展开更多
关键词 提取过程 受限射流 反应器 丁酸 磷酸丁酯 撞击速度 分数 体积传质系数
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Fractional Yield, Extract Composition and Variability from Jordanian Oil Shales 被引量:1
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作者 Hani M. Alnawafleh Feras Y. Fraige +2 位作者 Khalid E. Tarawneh Ibrahim A. Sarairahc Laila A. Al-Khatib 《Journal of Analytical Sciences, Methods and Instrumentation》 2016年第3期51-63,共13页
Surface and subsurface oil shale (OS) rocks in Jordan have potential economic value for the country and still unutilized. This research paper focuses on central and southern OS deposits in Jordan. Brief characterizati... Surface and subsurface oil shale (OS) rocks in Jordan have potential economic value for the country and still unutilized. This research paper focuses on central and southern OS deposits in Jordan. Brief characterization of four OS deposits is presented. Size distribution test and elemental analysis were performed. Shale oil was extracted via three solvation methods: Soxhlet extraction, extraction via mixing and stirring, and lastly super-critical fluid extraction. Major shale oil fractions were obtained from extract fractionation on chromatographic column. The nuclear magnetic resonance spectroscopy technique was used to study qualitatively the fractional composition of OS extract. Results show that all studied OS deposits have quite similar trend in their particle size distribution and their elemental composition. These OS deposits are found to be varying in their solvation behavior, fractional yield, and shale oil composition. Highest yield is obtained from polar solvents. The OS extraction via solvation processes is promising under certain extraction conditions such as super-critical conditions. The solvation variability of Jordanian OS indicates that different extraction techniques suit different OS deposits. Such variability should be considered in any future extraction options. 展开更多
关键词 JORDAN Oil Shale Solvent extraction VARIABILITY fractional Yield
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Mathematical module for countercurrently fractional chiral extraction and its VB simulation
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作者 唐课文 黄可龙 +1 位作者 易健民 张国丽 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2006年第6期1455-1459,共5页
Based on chemical thermodynamics and mass balance,countercurrently fractional chiral extraction by hollow fiber membrane was investigated.The mathematical modules for the relation of chiral extraction yield and produc... Based on chemical thermodynamics and mass balance,countercurrently fractional chiral extraction by hollow fiber membrane was investigated.The mathematical modules for the relation of chiral extraction yield and product optical purity with number of transfer units by chiral extraction with hollow fiber membrane were established,and the modules were simulated by visual basic(VB)proceduce.The results show that,the difference in free energy between two diastereomeric complexes formed by R-and S-enantiomer with chiral selector,??(?G),is the force of separation of enantiomers.It is necessary to separate enantiomers,where one of the extraction factors is above 1,and the other is below 1.Under certain phase ratio,chiral separation depends on separation factor and number of transfer units.The experimental result is in agreement with the theoretical value. 展开更多
关键词 fractionAL CHIRAL extractION mathematical MODULES VB SIMULATION
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Isocoreopsin: An active constituent of n-butanol extract of Butea monosperma flowers against colorectal cancer(CRC)
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作者 Boopathi Subramaniyan Navaneethakrishnan Polachi Ganeshan Mathan 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第5期318-325,共8页
The herb Butea monosperma constitutes several human health beneficial components, which are mostly studied for their anticancer effects. In this study, the activity of n-butanol fractions of B. monosperma floral extra... The herb Butea monosperma constitutes several human health beneficial components, which are mostly studied for their anticancer effects. In this study, the activity of n-butanol fractions of B. monosperma floral extract was examined on inhibiting aberrant crypt foci(ACF) formation in azoxymethane induced Wistar albino rats. The n-butanol extracts(150 mg/kg) decreased the ACF formation(per rat) by 92% and78% in short- and long-term in vivo treatments, respectively. All the compounds in the n-butanol extract were isolated and purified using column and reverse-phase high pressure liquid chromatography(HPLC).Their structures were characterized using UV–visible spectroscopy, nuclear magnetic resonance(NMR)and electrospray–ionisation mass spectrometry(ESI–MS) to determine important flavonoids, namely isocoreopsin, butrin and isobutrin. These compounds were studied for their free radical scavenging and anticancer activities. The compound isocoreopsin showed significantly greater efficacy in cell death on human colon and liver cancer cell lines(50 μg/m L in HT-29 and 100 μg/m L in Hep G2) than butrin(100 μg/m L in HT-29 and 500 μg/m L in Hep G2) and isobutrin(80 μg/m L in HT-29 and 150 μg/m L in Hep G2). These results suggest that isocoreopsin, butrin and isobutrin are the important key compounds for the chemoprevention of colon cancer and isocoreopsin can be considered as a promising novel drug. 展开更多
关键词 Butea monosperma n-butanol extractS Column CHROMATOGRAPHY HPLC Isocoreopsin
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Schisandra N-butanol extract improves synaptic morphology and plasticity in ovarectomized mice
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作者 Meiyan Yang Zhaolin Cai +1 位作者 Peng Xiao Chuhua Li 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第18期1365-1369,共5页
Preliminary work by our research team revealed that Schisandra, a renowned traditional Chinese medicine, causes learning and memory improvements in ovariectomized mice. This activity was attributed to active ingredien... Preliminary work by our research team revealed that Schisandra, a renowned traditional Chinese medicine, causes learning and memory improvements in ovariectomized mice. This activity was attributed to active ingredients extracted with N-butyl alcohol, named Schisandra N-butanol extract. In this study, ovariectomized mice were pretreated with Schisandra N-butanol extract given by intragastric administration. This treatment led to the enhancement of learning, and an increase in hippocampal CA1 synaptic, surface and postsynaptic density. A decrease in the average size of the synaptic active zone was also observed. These experimental findings showing that Schisandra N-butanol extract improved synaptic morphology indicate an underlying mechanism by which the ability of learning is enhanced in ovariectomized mice. 展开更多
关键词 Schisandra n-butanol extract OVARIECTOMY MICE behavioral learning hippocampal CA1" synapticmorphology synaptic density neural regeneration
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Key Frame Extraction of Surveillance Video Based on Fractional Fourier Transform
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作者 Yunzuo Zhang Jiayu Zhang Ran Tao 《Journal of Beijing Institute of Technology》 EI CAS 2021年第3期311-321,共11页
With the vigorous development of national infrastructure construction and public information construction,video surveillance systems have gradually penetrated various fields.The current key frame extraction technology... With the vigorous development of national infrastructure construction and public information construction,video surveillance systems have gradually penetrated various fields.The current key frame extraction technology has inadequate target details and inaccurate judgment of local actions.Addressing this problem,a key frame extraction method based on fractional Fourier transform is proposed.This method obtained the phase spectra information of different orders by performing fractional Fourier transform on the surveillance video frames.Next,the method designed an adaptive algorithm based on the golden section point to select the transformation order.Then,the phase spectrum information of two adjacent frames was used to characterize the changes in the global and local motion states of the target.The final step was to extract key frames based on this.Experimental results show that,compared with the previous methods,the key frames extracted by the method proposed in this paper can correctly capture the changes in the global and local motion states of the target. 展开更多
关键词 fractional Fourier transform(FRFT) phase spectrum key frame extraction adapta-tion local motion status
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承压破碎无烟煤气体渗透特性影响因素实验研究
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作者 李振 余奕睿 +6 位作者 王红伟 冯国瑞 何富连 王德璋 周劲辉 柳路妍 韩鑫磊 《煤田地质与勘探》 EI CAS CSCD 北大核心 2024年第3期1-13,共13页
垮落带破碎煤岩体空隙结构演变直接影响垮落带气体渗透特性,进而影响废弃矿井采空区煤层气运移富集规律。利用自主设计研发的第二代破碎煤岩体压实-渗流-CT扫描试验系统,开展5种粒径破碎无烟煤在不同气体压力、轴向应力及空隙率条件下16... 垮落带破碎煤岩体空隙结构演变直接影响垮落带气体渗透特性,进而影响废弃矿井采空区煤层气运移富集规律。利用自主设计研发的第二代破碎煤岩体压实-渗流-CT扫描试验系统,开展5种粒径破碎无烟煤在不同气体压力、轴向应力及空隙率条件下162组渗透实验。结果表明:(1)气体在破碎无烟煤中运移时气体压力、流量随时间一直处于动态变化直至达到吸附平衡,流量、压力恒定。(2)低雷诺数下气体在破碎无烟煤中流动需要拟启动压力梯度,其值处于158.89~1408.64 Pa/m,并随着轴压增大、空隙率减小而增大。(3)破碎无烟煤渗透率处于10^(-12)~10^(-10)m^(2),且渗透率随气体压力、空隙率增加分别呈现对数、指数函数式增长趋势。(4)颗粒粒径越大则相同装料空间内破碎煤样初始空隙越大,更易于气体流动,因此相同空隙率时破碎无烟煤渗透率随粒径的增大而增大;不同粒径颗粒渗透率平均变化幅度均随空隙率减小而减小;然而颗粒粒径越大,减小相同空隙率时破碎无烟煤渗透率变化幅度减小越明显。废弃矿井采空区煤层气地面抽采时,地面钻井应优先布设在垮落带破碎煤岩体连同纵向“高位环形裂隙体”共同构成的“U”型高渗煤层气富集区内。 展开更多
关键词 瓦斯抽采 废弃矿井采空区 破碎煤 气体压力 空隙率 粒径 渗透率
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木质素抑菌性能强化改性方法研究进展
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作者 王硕 张健本 +1 位作者 甘心权 谢彩锋 《应用化工》 CAS CSCD 北大核心 2024年第5期1205-1208,1213,共5页
综述了木质素的结构特征,说明了木质素对革兰氏阳性菌和革兰氏阴性菌的抑菌机理,即酚羟基能促进细胞周围pH值的降低,从而可以破坏细胞膜,使蛋白质变性,抑制微生物细胞的呼吸系统和电子传递酶系统活性,达到抑菌作用,而分子量降低可以提... 综述了木质素的结构特征,说明了木质素对革兰氏阳性菌和革兰氏阴性菌的抑菌机理,即酚羟基能促进细胞周围pH值的降低,从而可以破坏细胞膜,使蛋白质变性,抑制微生物细胞的呼吸系统和电子传递酶系统活性,达到抑菌作用,而分子量降低可以提高木质素酚羟基含量,亲水性提高则可有效提高木质素水溶性。结合国内外研究现状,介绍了提高木质素抑菌活性的主要方法:解聚法、分级法、木质素的提取方法和木质素-银络合物法,阐述了不同方法改性木质素如何提高其抑菌活性,并对提高木质素抑菌活性研究进行展望。 展开更多
关键词 木质素 抑菌 解聚 分级 提取 络合
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