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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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Chemical compositions and biological activities of Flos lonicerae
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作者 Yi’an Shi Luming Pan +3 位作者 Luyan Yang Jing Sun Meng Zhang Yu Chen 《Asian Journal of Traditional Medicines》 CAS 2023年第2期60-68,共9页
Flos lonicerae is the dry flower bud of Lonicera japonica Thunb,and it is a very important Chinese herbal medicine in China.In ancient times,it was widely used to treat the exopathogenic wind-heat,epidemic febrile dis... Flos lonicerae is the dry flower bud of Lonicera japonica Thunb,and it is a very important Chinese herbal medicine in China.In ancient times,it was widely used to treat the exopathogenic wind-heat,epidemic febrile diseases,sores,carbuncles and some infectious diseases.Modern pharmacological research has indicated that it has anti-inflammatory,anti-bacterial,anti-viral and anti-oxidation activities.This paper reviews the chemical compositions and biological activities of Flos lonicerae in order to provide reference for its application in clinical practice in the future. 展开更多
关键词 Flos lonicerae chemical composition biological activity
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Chemical compositions of sulfides in the porphyry Cu ores,Yangla Cu deposit,Yunnan,China:implication for ore genesis 被引量:3
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作者 Xinfu Wang Bo Li +2 位作者 Zuopeng Xiang Yan Yue Guo Tang 《Acta Geochimica》 EI CAS CSCD 2020年第6期947-972,共26页
The Yangla Cu deposit is the largest ore deposit in the Jinshajiang polymetallic metallogenic belt,northwest Yunnan,China.There is no consensus on the genesis of the ore deposit owing to the limited studies on the che... The Yangla Cu deposit is the largest ore deposit in the Jinshajiang polymetallic metallogenic belt,northwest Yunnan,China.There is no consensus on the genesis of the ore deposit owing to the limited studies on the chemical compositions of sulfides.This study used an electron probe micro-analyzer to constrain the chemical compositions of pyrite,chalcopyrite,molybdenite,and sphalerite in the porphyry Cu ore of the Yangla Cu deposit and compared them with the chemical compositions of sulfides in the skarn Cu ore.The trace element contents and their occurrences were used to estimate the metallogenic temperature and infer the genesis of the Yangla deposit.The results show that the sulfides in the porphyry Cu ores have variations of ore element concentrations relative to their theoretical values.Pyrite is depleted in S but elevated in Fe;chalcopyrite is depleted in Cu,Fe,and S;and molybdenite and sphalerite are enriched in S whilst depleted in Mo and Zn.The concentrations of the main metallogenic elements Cu,Fe,Mo,Zn,and S in the porphyry are generally lower than those in skarn,suggesting that the porphyry ore was formed in a moderate to moderate-high temperature metallogenic environment.The formation time may also be slightly later than that of the skarn Cu ore.Elements such as As,Co,Cu.Pb,Zn,Mo,Cd,and Ni mainly exist as isomorphic replacements and mineral inclusions in the sulfides of both porphyry and skarn Cu ores.The trace element features of sulfides in the two ore bodies show that the Yangla Cu deposit may be a composite super imposed ore deposit,and让s formation has undergone the process of exhalative-sedimentary to skarnporphyry mineralization. 展开更多
关键词 Sulfides Trace elements chemical composition Yangla Cu deposit YUNNAN
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Design and control of chemical compositions for high-performance austempered ductile iron 被引量:2
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作者 Gong Wenbang Chen Guodong +2 位作者 Luo Li Hao Jing Zhang Zhonghe 《China Foundry》 SCIE CAS 2012年第2期143-147,共5页
This paper presents the effects of chemical compositions of austempered ductile iron(ADI)on casting quality,heat treatment process parameters and mechanical properties of final products.Through experiment and producti... This paper presents the effects of chemical compositions of austempered ductile iron(ADI)on casting quality,heat treatment process parameters and mechanical properties of final products.Through experiment and production practice,the impacts of carbon equivalent on ADI and its mechanical properties have been studied. Proper content ranges for carbon and silicon have been obtained to avoid ADI casting shrinkage and graphite floatation,as well as to achieve the optimal mechanical properties.According to the impact of silicon content on austenite phase transformation,the existing form of carbon in ADI has been analyzed,and also the formula and diagram showing the relationship between austenitizing temperature and carbon content in austenite have been deduced.The chemical composition range for high performance ADI and its control points have been recommended, to serve as a reference for production process. 展开更多
关键词 austempered ductile iron chemical composition composition control
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Chemical Compositions of Stemmacantha carthamoides Root
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作者 Yining ZHONG Huan LIU Jinhui WANG 《Medicinal Plant》 CAS 2018年第1期13-15,共3页
[Objectives] Chemical compositions of S. carthamoides root were isolated and identified. [Methods]Solvent extraction,repeated silica gel column chromatography,ODS column chromatography,preparative liquid chromatograph... [Objectives] Chemical compositions of S. carthamoides root were isolated and identified. [Methods]Solvent extraction,repeated silica gel column chromatography,ODS column chromatography,preparative liquid chromatography and recrystallization were used for separation and purification,and chemical structure of compound was identified via its physical-chemical properties and spectral analysis data.[Results] Eight compounds were obtained from methanol extract of S. carthamoides root: 24-ethyl-20-oxhydryl ecdysone( 1),β-ecdysterone( 2),Ajugasterone C( 3),3,4-DHBA( 4),3-methoxy-quercetin( 5),( 7 S,8 S)-syringoylglycerol( 6),( E)-3,7-dimethyl-1-O-[α-L-arabinofuranosyl-( 1→6)-β-D-glucopyranosy1]-oct-2-en-7-ol( 7),Polypodine B( 8). [Conclusions] Compounds 6 and 7 were firstly isolated from the plant. 展开更多
关键词 Stemmacantha carthamoides root chemical composition Extraction and separation Structure identification
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Wood Density of Ten Native Trees and Shrubs and Its Possible Relation with a Few Wood Chemical Compositions
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作者 Ratikanta Maiti Humberto Gonzalez Rodriguez Aruna Kumari 《American Journal of Plant Sciences》 2016年第8期1192-1197,共6页
The present study was undertaken in Forest Science Faculty, Universidad de Nuevo Leon, Mexico on variability of Wood density and its possible relation to few wood chemical composition and wood fiber cell structure ana... The present study was undertaken in Forest Science Faculty, Universidad de Nuevo Leon, Mexico on variability of Wood density and its possible relation to few wood chemical composition and wood fiber cell structure anatomy. The results reveal that among 10 specie studied, there exist a large variation in wood density (0.51 to 1.09), and few wood chemical composition such % carbón (37.14 to 44.07), nitrogen (9.18 to 19.22), sulphur (31.45 to 33/82), lignin (15/28 to 24.35), hemicellulose (19.94 to 27.36%), and % cellulose (33.69 to 45.92). In general, though there was no clear relationship between wood density and other chemical composition of wood. It was observed that the species having moderate to high wood density contained >40% carbón, >30% sulphur and >40% cellulose and more or less 20% lignin. It seems that carbón, sulphur, cellulose and lignin content contribute to greater density. The wood fiber cell with wall lignification seems to be related to higher wood density. 展开更多
关键词 Wood Density Wood chemical Composition CELLULOSE LIGNIN Carbón Concentration Variability
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Chemical constituents and pharmacological effects of Croton crassifolius
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作者 Luyan Yang Yibo Wang +4 位作者 Xinyao Wang Xiaoxia Xu Yunpeng Yang Meng Zhang Yu Chen 《Asian Journal of Traditional Medicines》 2024年第2期99-114,共16页
Croton crassifolius(CC)is a kind of traditional Chinese medicine rich in terpenoids,with among which diterpene species are the most.CC had biological activities in the treatment of cancer,inflammation,ulcerative colit... Croton crassifolius(CC)is a kind of traditional Chinese medicine rich in terpenoids,with among which diterpene species are the most.CC had biological activities in the treatment of cancer,inflammation,ulcerative colitis,osteoporosis and Alzheimer’s disease.This study reviews the chemical compositions and pharmacological activities of CC to provide reference for further research. 展开更多
关键词 Croton crassifolius chemical compositions pharmacological activities
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Effects of dietary Clostridium butyricum and rumen protected fat on meat quality,oxidative stability,and chemical composition of finishing goats
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作者 Meimei Zhang Zhiyue Zhang +9 位作者 Xinlong Zhang Changming Lu Wenzhu Yang Xiaolai Xie Hangshu Xin Xiaotan Lu Mingbo Ni Xinyue Yang Xiaoyang Lv Peixin Jiao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期911-924,共14页
Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide ... Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide essential fatty acids.However,it is still unknown whether dietary supplementation with CB and RPF exerts beneficial effects on growth performance and nutritional value of goat meat.This study aimed to investigate the effects of dietary CB and RPF supplementation on growth performance,meat quality,oxidative stability,and meat nutritional value of finishing goats.Thirty-two goats(initial body weight,20.5±0.82 kg)were used in a completely randomized block design with a 2 RPF supplementation(0 vs.30 g/d)×2 CB supplementation(0 vs.1.0 g/d)factorial treatment arrangement.The experiment included a 14-d adaptation and 70-d data and sample collection period.The goats were fed a diet consisted of 400 g/kg peanut seedling and 600 g/kg corn-based concentrate(dry matter basis).Result Interaction between CB and RPF was rarely observed on the variables measured,except that shear force was reduced(P<0.05)by adding CB or RPF alone or their combination;the increased intramuscular fat(IMF)content with adding RPF was more pronounced(P<0.05)with CB than without CB addition.The pH24h(P=0.009),a*values(P=0.007),total antioxidant capacity(P=0.050),glutathione peroxidase activities(P=0.006),concentrations of 18:3(P<0.001),20:5(P=0.003)and total polyunsaturated fatty acids(P=0.048)were increased,whereas the L*values(P<0.001),shear force(P=0.050)and malondialdehyde content(P=0.044)were decreased by adding CB.Furthermore,CB supplementation increased essential amino acid(P=0.027),flavor amino acid(P=0.010)and total amino acid contents(P=0.024)as well as upregulated the expression of lipoprotein lipase(P=0.034)and peroxisome proliferator-activated receptorγ(PPARγ)(P=0.012),and downregulated the expression of stearoyl-CoA desaturase(SCD)(P=0.034).The RPF supplementation increased dry matter intake(P=0.005),averaged daily gain(trend,P=0.058),hot carcass weight(P=0.046),backfat thickness(P=0.006),concentrations of 16:0(P<0.001)and c9-18:1(P=0.002),and decreased the shear force(P<0.001),isoleucine(P=0.049)and lysine content(P=0.003)of meat.In addition,the expressions of acetyl-CoA carboxylase(P=0.003),fatty acid synthase(P=0.038),SCD(P<0.001)and PPARγ(P=0.022)were upregulated due to RPF supplementation,resulting in higher(P<0.001)content of IMF.Conclusions CB and RPF could be fed to goats for improving the growth performance,carcass traits and meat quality,and promote fat deposition by upregulating the expression of lipogenic genes of Longissimus thoracis muscle. 展开更多
关键词 chemical composition Clostridium butyricum Goats Meat quality Oxidative stability Rumen protected fat
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Extraction,chemical components,bioactive functions and adulteration identification of walnut oils:A review
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作者 Yuan Gao Jia Hu +6 位作者 Xia Su Qi Li Caihong Su Yongling Li Gaiqin Ma Siyu Zhang Xiuzhu Yu 《Grain & Oil Science and Technology》 CAS 2024年第1期30-41,共12页
Walnut oil is a functional wood oil known to researchers that may potentially be a large source of Chinese edible oils.There are various extraction methods for walnut oil,including traditional(pressing,solvent-and enz... Walnut oil is a functional wood oil known to researchers that may potentially be a large source of Chinese edible oils.There are various extraction methods for walnut oil,including traditional(pressing,solvent-and enzymeassisted extraction)and novel methods(microwave,ultrasound,supercritical CO_(2),subcritical and other extraction technologies).Walnut oil is rich in nutrients,including phytosterols,tocopherols,polyphenols,squalene and minerals.It provides many health benefits,such as antioxidant,antitumor,anti-inflammatory,antidiabetic and lipid metabolism-related functions.In addition,the authentication of walnut oil has received much research attention.The present review provides detailed research on walnut oil extraction,composition,health benefits and adulteration identification methods.The path toward further walnut oil improvement in the context of the market value of walnut oil is also discussed. 展开更多
关键词 Extraction technology chemical composition Bioactive AUTHENTICATION
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Chemical constituents and pharmacological effects of Lonicerae japonicae
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作者 Yunpeng Yang Dan Tian +3 位作者 Yibo Wang Yi’an Shi Yuntian Xing Yu Chen 《Asian Journal of Traditional Medicines》 2024年第1期34-45,共12页
Lonicera japonica,also known as honeysuckle,is an evergreen shrub in the family of Syzygium.By consulting Sciencedirect databases and Web of Science databases,79 related articles were found,of which 22 were related to... Lonicera japonica,also known as honeysuckle,is an evergreen shrub in the family of Syzygium.By consulting Sciencedirect databases and Web of Science databases,79 related articles were found,of which 22 were related to chemical composition and pharmacological activity.These articles show that L.japonica has a wide range of pharmacological activities,including antiviral,anti-tumor,and antioxidant effects.These activities have important applications in the pharmaceutical,food,and fragrance industries.This review focuses on the chemical composition and pharmacological effects of L.japonicae,which is of great significance to the development of new drugs and therapeutic methods. 展开更多
关键词 Lonicerae japonicae chemical composition pharmacological activity
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Comparison of inorganic chemical compositions of atmospheric TSP,PM10 and PM2.5 in northern and southern Chinese coastal cities 被引量:2
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作者 Yiding Ma Zongshuang Wang +5 位作者 Yufei Tan Shu Xu Shaofei Kong Gang Wu Xuefang Wu Hong Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第5期339-353,共15页
To compare the inorganic chemical compositions of TSP(total suspended paniculate),PM_(10)(particulate matter with an aerodynamic diameter less than 10 μm) and PM_(2.5)(particulate matter with an aerodynamic diameter ... To compare the inorganic chemical compositions of TSP(total suspended paniculate),PM_(10)(particulate matter with an aerodynamic diameter less than 10 μm) and PM_(2.5)(particulate matter with an aerodynamic diameter less than 2.5 μm) in southern and northern cities in China,atmospheric particles were synchronously collected in Dalian(the northern city)and Xiamen(the southern city) in spring and autumn of 2004.The mass concentrations,twenty-three elements and nine soluble ions were assessed.The results show that in Dalian,the mass concentrations of Mg,Al,Ca,Mn and Fe in spring were 4.0-10.1,2.6-8.0,4.1-12,1.2-3.6 and 2.9-7.9 times higher,respectively,than those in Xiamen.The dust storm influence is more obvious in Dalian in spring.However,in Xiamen,heavy metals accounted for 13.9%-17.9%of TSP,while heavy metals contributed to 5.5%-9.3%of TSP in Dalian.These concentrations suggest that heavy metal pollution in Xiamen was more serious.In addition,the concentrations of Na^+,Cl^-,Ca^(2+) and Mg^(2+) were higher in Dalian due to the influence of marine aerosol,construction activities and soil dust.The NO^(3-)/SO_4^(2-) ratios in Dalian(0.25-0.49) were lower than those in Xiamen(0.51-0.62),indicating that the contributions of vehicle emission to particles in Xiamen were higher.Coefficient of divergence values was higher than 0.40,implying that the inorganic chemical composition profiles for the particles of Dalian and Xiamen were quite different from each other. 展开更多
关键词 Particulate matter Inorganic chemical compositions DIFFERENCES Dalian city Xiamen city
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Effects of relative humidity and PM2.5 chemical compositions on visibility impairment in Chengdu, China 被引量:21
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作者 Fan Liu Qinwen Tan +2 位作者 Xia Jiang Fumo Yang Wenju Jiang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第12期15-23,共9页
To better understand the potential causes of visibility impairment in autumn and winter in Chengdu,relative humidity(RH),visibility,the concentrations of PM2.5 and its chemical components were on-line measured continu... To better understand the potential causes of visibility impairment in autumn and winter in Chengdu,relative humidity(RH),visibility,the concentrations of PM2.5 and its chemical components were on-line measured continuously in Chengdu from Nov.2016 to Jan.2017.Six obvious haze episodes occurred in Chengdu,with the total time of haze episodes accounted for more than 90%of the total observation period,and higher NO2 concentrations and RH were related to the high particle concentrations in haze episodes.The visibility decreased in a non-linear tendency under different RH conditions with the increase of PM2.5 concentrations,which was more sensitive to RH under lower PM2.5 concentrations.The threshold concentration of PM2.5 got more smaller with the increase of RH.During the entire observation period,organic matter(OM)was the largest contributor(31.12%to extinction coefficient(bext)),followed by NH4NO3 and(NH4)2SO4 with 28.03%and 23.01%,respectively.However,with the visibility impairment from Type I(visibility>10 km)to Type IV(visibility≤2 km),the contribution of OM to bextdecreased from 38.12%to 26.77%,while the contribution of NH4NO3 and(NH4)2SO4 to bextincreased from 19.09%and 20.20%to 34.29%and 24.35%,respectively,and NH4NO3 became the largest contributor to bextat Type IV.The results showed that OM and NH4NO3 were the key components of PM2.5 for visibility impairment in Chengdu,indicating that the control of precursors emissions of carbonaceous species and NH4NO3 could effectively improve the visibility in Chengdu. 展开更多
关键词 Visibility impairment PM2.5 chemical composition Relative humidity Light extinction coefficient Secondary formation
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Concentrations and chemical compositions of PM10 during hazy and non-hazy days in Beijing 被引量:5
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作者 Xianchu Wu Bin Chen +2 位作者 Tianxue Wen Ammara Habib Guangyu Shi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第1期1-9,共9页
In order to study the concentrations of major components,characteristics and comparison in hazy and non-hazy days of PM10 in Beijing,aerosol samples were collected at urban site in Beijing from December 29,2014 to Jan... In order to study the concentrations of major components,characteristics and comparison in hazy and non-hazy days of PM10 in Beijing,aerosol samples were collected at urban site in Beijing from December 29,2014 to January 22,2015.Heavy metals like Zn,Pb,Mn,Cu,As,V,Cr and Cd were deeply studied considering their toxic effects on human being;nine water-soluble inorganic ions(SO4^2-,NO3^-,NH4^+,Na^+,K^+,Cl^-,Ca^2+and Mg^2+)and carbon fractions(OC and EC)were also analyzed.The concentrations of heavy metals were 1.03–1.98 times higher in hazy days than those in non-hazy days,mainly due to biomass burning and coal burning.The trends in total heavy metals concentrations were basically consistent with the trends in PM concentrations except for two obvious periods(12.29–12.30;1.14–1.15);but when air masses accumulated locally or around Beijing,trends in PM concentrations and heavy metals were opposite.The proportion for NO3^-/SO4^2-indicated that mobile sources such as automobiles were important reasons for haze in Beijing.Correlation between OC and EC during non-hazy days was strong(R^2=0.95)but it was low(R^2=0.67)during hazy days,and large variations for OC/EC values occurred in hazy days.The calculated mass concentration of SOC is 2.58μg/m^3,which only accounted for 10.1%of the OC concentration.When air masses from the far north-west,they decreased PM concentration in Beijing and they were relatively clean;however,those from the near east,south-east and south of the mainland increased PM concentration and they were dirty. 展开更多
关键词 PM10 HAZE BEIJING chemical composition Air mass
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Effect of microbial fermentation on the sensory characteristics and chemical compositions of Chinese sweet tea(Lithocarpus litseifolius(Hance)Chun) 被引量:2
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作者 Weimin Huang Changyi Zhang +10 位作者 Zepeng Gu Cheng Li Zhengfeng Fang Zhen Zeng Zhiqing Zhang Bin Hu Hong Chen Wenjuan Wu Tiqiang Wang Xiguo Lan Yuntao Liu 《Food Bioscience》 SCIE 2022年第2期572-584,共13页
Sweet tea,which has hundreds of years of use among in Chinese folk,is a traditional herbal tea with pleasant sweetness,bitterness and astringency.In the current study,we used traditional microbial fermentation to impr... Sweet tea,which has hundreds of years of use among in Chinese folk,is a traditional herbal tea with pleasant sweetness,bitterness and astringency.In the current study,we used traditional microbial fermentation to improve sensory characteristics of sweet tea,especially for the reduction of bitterness and astringency.The dynamic changes of non-volatile,volatile compounds and microbial community were investigated during microbial fermentation.The contents of polyphenols,flavonoids,soluble sugar,soluble protein,catechins and dihydrochalcones decreased significantly while the tea pigments,free amino acids and gallic acid content inversely increased during microbial fermentation.A total of 61 volatile compounds were identified and quantified in sweet tea,of which 20 key compounds were identified as odor active compounds(OAV),including 3 aldehydes,1 ketone,4 alcohols,9 esters,4 alkenes and 3 other compounds.In addition,eight fungi and four bacteria were considered as core microorganisms,such as Aspergillus,Alternaria,Cladosporium,Epicoccum,Itersonilia,Penicillium,Periconia,Wallemia,Aureimonas,Enterobacter,Klebsiella and Stenotrophomonas,which were significantly correlated with non-volatile compounds and flavor compounds.These results provided theoretical guidance for processing of fermented sweet tea. 展开更多
关键词 Sweet tea Microbial fermentation Sensory characteristics chemical composition Microbial community
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A Study on Chemical Compositions and Fiber Characteristics of Two Sympodial Bamboos 被引量:1
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作者 FENG Wenying WANG Zheng GUO Wenjing China National Pulp and paper Research InstituteBeijing 100020. P.R.China Research Institute of Wood Industry. CAF.Beiiine 100091. P.R.China 《Chinese Forestry Science and Technology》 2003年第3期90-95,共6页
The chemical composition and fiber characteristics of two sympodial bamboos have been studied in this paper. Based on analysis results, it is shown that the Whangee (D. Membranaceus Munro) bamboo is better than Yunnan... The chemical composition and fiber characteristics of two sympodial bamboos have been studied in this paper. Based on analysis results, it is shown that the Whangee (D. Membranaceus Munro) bamboo is better than Yunnanicus bamboo(D. yunnaicus Hsueh et D. Z. Li) in utilization because of its higher specific gravity, better fiber length and its distribution rule and higher wall/lumen ratio, and that the Whangee bamboo is more suitable for papermaking and panel processing used in house construction. In addi... 展开更多
关键词 sympodial bamboo chemical composition fiber characteristics ANALYSIS
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Optimizing yield and chemical compositions of dimethylsulfoxide-extracted birchwood xylan
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作者 Mingquan Zhang Jamshed Bobokalonov +1 位作者 Abduvali Dzhonmurodov Zhouyang Xiang 《Journal of Bioresources and Bioproducts》 EI 2022年第3期211-219,共9页
Dimethylsulfoxide(DMSO)extraction is commonly used to study the chemical structures of orig-inal xylan in the plant cell wall,since the DMSO can preserve the original structure of the xylan as much as possible during ... Dimethylsulfoxide(DMSO)extraction is commonly used to study the chemical structures of orig-inal xylan in the plant cell wall,since the DMSO can preserve the original structure of the xylan as much as possible during the extracting process.In addition,the DMSO-extracted xylans have unique properties allowing their potential applications in emulsifying or filming materials.How-ever,the yield of DMSO-extracted xylan is always low and the effects of different DMSO extraction conditions on the chemical compositions of xylan have not been fully studied,which greatly hin-ders its researches and applications.In this study,we have found that extensive delignification before DMSO extraction results in destruction of lignin-carbohydrate complex(LCC),leading to xylan yield and xylose unit content increased by up to 220%and 20%,respectively.Tert-butanol washing of the holocellulose can further increase the DMSO extracted xylan yield by∼10%.The yield of xylan extracted by the DMSO at 80°C for 7 h was obviously higher than that at room temperature for 3 d by 30%-40%.Thermal analysis showed that the xylans extracted at differ-ent conditions had thermal stability without obvious differences.The results indicate that the DMSO-extracted xylan with a high yield,a high purity and a high degree of acetylation can be ex-tracted at a high delignification level,a high reaction temperature and a short reaction time.This study is of great significance for studying xylan structure-property relationships and promoting the applications of DMSO-extracted xylan. 展开更多
关键词 XYLAN Dimethylsulfoxide(DMSO)extraction Birchwood YIELD chemical composition
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Chemical Variation of Chromian Spinel Compositions in a Serpentinized Peridotites: Implications for Evolution of the Neoproterozoic Ophiolites
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作者 Hamed Gamal EL DIEN Tomoaki MORISHITA +3 位作者 Mohamed HAMDY Abdel Salam ABU EL-ELA Adel HASSAN Yusuke SODA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期210-,共1页
Tectonic setting of the Neoproterozoic ophiolites is poorly understood.Because of extensive serpentinization/metamorphism in the mantle section,accessory chromian spinel has been used as an important geotectonic indic... Tectonic setting of the Neoproterozoic ophiolites is poorly understood.Because of extensive serpentinization/metamorphism in the mantle section,accessory chromian spinel has been used as an important geotectonic indicator. 展开更多
关键词 chemical Variation of Chromian Spinel compositions in a Serpentinized Peridotites Implications for Evolution of the Neoproterozoic Ophiolites
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Physicochemical Properties of Combustion Ashes of Some Trees(Urban Pruning)Present in the Neotropical Region
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作者 John Freddy Gelves-Díaz Ludovic Dorkis +2 位作者 Richard Monroy-Sepúlveda Sandra Rozo-Rincón Yebrail Alexis Romero-Arcos 《Journal of Renewable Materials》 EI 2023年第10期3769-3787,共19页
Secondary lignocellulosic biomass has proved to be useful as an energy source through its oxidation by means of combustion processes.In accordance with the above,in this paper,we wanted to study the ash from urban pru... Secondary lignocellulosic biomass has proved to be useful as an energy source through its oxidation by means of combustion processes.In accordance with the above,in this paper,we wanted to study the ash from urban pruning residues that are generated in cities in the Neotropics.Species such as Licania tomentosa,Azadirachta indica,Ficus benjamina,Terminalia catappa,Leucaena leucocephala,Prosopis juliflora and Pithecellobium dulce were selected because they have been previously studied and showed potential for thermal energy generation.These materials were calcined in an oxidizing atmosphere and characterized by X-ray diffraction and fluorescence,scanning electron microscopy with microchemistry,BET surface area,thermal gravimetric analysis,and differential scanning calorimetry.The pH and apparent density were also established.The results show high basicity materials(average pH 10),a behavior associated with the presence of chemical elements such as calcium,potassium,magnesium,chlorine,phosphorus,and sulfur.Structurally,these materials have a very significant amorphous fraction(between 49%and 74.5%),the dominant crystalline phases are calcite,arcanite,sylvite,and hydroxyapatite.These ashes have low surface area and do not exceed 13 m^(2)/g.Two characteristic morphological aspects were observed in these ashes:a morphology of rounded grains where silicon content is highlighted,and lamellar morphologies where the presence of chlorine is highlighted.Thermally,these ashes show four significant mass loss events(400℃,430℃,680℃,and 920℃),causing mass losses that vary between 25%and 40%.Through this study,it was possible to establish that,from a chemical point of view,these ashes are less dangerous in comparison with those of a mineral coal that was used as a reference.However,they require additional treatments for their disposal due to their high basicity.Because of their composition,these ashes have the potential to be used in the ceramic and cement industries,and in the manufacture of fertilizers. 展开更多
关键词 Bottom ash chemical composition characterization MINERALOGY plant biomass pruning residues urban flora
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Chemical Composition of Sphyraena barracuda with Different Area, Size and Season, in Sudanese Red Sea Coast
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作者 Hala Gindeel A. Ahmadoon Abdall N. Elawad +1 位作者 Alamin M. Alamin Adam A. Babiker 《Food and Nutrition Sciences》 CAS 2023年第5期415-420,共6页
This study aims to determine the effect of area, size and season on chemical composition of Sphyraena barracuda from Sudanese Red Sea Coast. A total of 180 fish samples were collected from Port Sudan and Sawakin fishi... This study aims to determine the effect of area, size and season on chemical composition of Sphyraena barracuda from Sudanese Red Sea Coast. A total of 180 fish samples were collected from Port Sudan and Sawakin fishing sites during the winter and summer of 2020-2021. The fishes sample ranged between (30 - 50) cm in total length and (250 - 1000) gm in body weight of small size, and ranged between (60 - 90) cm in total length and (1250 - 250) gm in body weight for large size. Fish flesh was subject to gross chemical analysis. Moisture, protein, fat, ash, acidity and pH were determined. The results indicated a significant effect by area, season and size. The different areas had a significant effect on crude protein and ash;higher parameter value is found in Sawakin. Higher chemical parameters were showed in winter than in summer. Also, size had a significant effect in all parameters (except moisture), fat and ash were high in large size. The study has concluded that the large size fishes of S. barracuda with high nutritional value when caught in winter from the southern region of Sawakin. 展开更多
关键词 Area chemical Composition Season and Size
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A review of research on the chemical constituents and pharmacological effects of Elephantopus tomentosus L.
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作者 Shuai Shen Ming Bai Shaojiang Song 《Asian Journal of Traditional Medicines》 CAS 2023年第1期15-24,共10页
Elephantopus tomentosus,belonging to the genus Elephantopus,is widely distributed in the coastal areas of southern China and tropical regions,used locally as traditional folk medicine.Previous phytochemistry studies o... Elephantopus tomentosus,belonging to the genus Elephantopus,is widely distributed in the coastal areas of southern China and tropical regions,used locally as traditional folk medicine.Previous phytochemistry studies on Elephantopus tomentosus led to the isolation of sesquiterpenoids,triterpenoids,flavonoids and other compounds.Research has shown that these compounds possess multiple biological activities,which have attracted great attention of researchers worldwide.This study reviews the chemical constituents and biological activities of the Elephantopus tomentosus in order to better explore and utilize Elephantopus tomentosus. 展开更多
关键词 Elephantopus tomentosus chemical composition pharmacological activities SESQUITERPENOIDS
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