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Chemical Compositions of Volatile Oil from Fruiting Body of Armillaria luteo-virens 被引量:30
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作者 周劲松 熊辉岩 +2 位作者 杨春江 焦迎春 盛海彦 《Agricultural Science & Technology》 CAS 2008年第2期90-92,共3页
The chemical compositions of volatile oil from fruiting body of Armillaria luteo-virens in Qinghai Province were firstly analyzed with GC-MS and its relevant compositions were detected by calculating chromatographic p... The chemical compositions of volatile oil from fruiting body of Armillaria luteo-virens in Qinghai Province were firstly analyzed with GC-MS and its relevant compositions were detected by calculating chromatographic peak area with normalized method. 21 peaks were separated and 13 compositions were identified which were mainly unsaturated fatty acids, taking 97.1% of the total volatile oil. 展开更多
关键词 Armillaria luteo-rirens Volatile oil chemical compositions GC-MS
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Chemical compositions and pharmacological activities ofXanthium strumarium
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作者 Ruoming Li Yunpeng Yan +4 位作者 Xiaomeng Zhangc Yibo Wang Wenhan Wang Yao Zhao Yu Chena 《Asian Journal of Traditional Medicines》 2024年第6期342-352,共11页
Xanthium strumarium(X.strumarium)is a traditional Chinese medicine with a long history.In recent years,with the development of modern pharmacology and chemical analysis technology,research on X.strumarium has been dee... Xanthium strumarium(X.strumarium)is a traditional Chinese medicine with a long history.In recent years,with the development of modern pharmacology and chemical analysis technology,research on X.strumarium has been deepend.This paper aims to systematically summarize the chemical compositions and pharmacological effects of X.strumarium,in order to provide theoretical basis and reference for further exploration in its clinical application and drug development. 展开更多
关键词 Xanthium strumarium chemical composition pharmacological activities
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Study on Main Chemical Compositions of Rice Straw in Three Different Areas of Jiangsu Province 被引量:1
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作者 宋卫东 王教领 +3 位作者 王明友 吴今姬 李尚昆 王培雨 《Agricultural Science & Technology》 CAS 2016年第2期405-408,共4页
[Objective] The research was aimed to study the main chemical composi- tions of rice straw in the three different areas of Jiangsu Province. [Method] The cellulose, hemicellulose, lignin and crude ash of rice straw co... [Objective] The research was aimed to study the main chemical composi- tions of rice straw in the three different areas of Jiangsu Province. [Method] The cellulose, hemicellulose, lignin and crude ash of rice straw collected in Huaian, Changzhou and Zhenjiang of Jiangsu Province during 2011-2013 were determined. [Result] The change trends of cellulose and hemicellulose in three arrears in differ- ent years were consistent. The cellulose content increased after falling, and hemi- cellulose content presented declining tendency. The lignin content of rice straw fist rose then declined in Huaian and Changzhou in different years, while it presented the declining tendency in Zhenjiang. The ash content of rice straw changed little and was all less than 65% in the three areas in different years. And the chemical composition of rice straw changed significantly in different years. [Conclusion] The research could provide basis for high added-value use of crop straw. 展开更多
关键词 Rice straw Different years chemical composition Jiangsu Province
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Comparison on the Chemical Compositions in the K326 Tobacco from Different Tobacco-planting Areas of Yunnan Province 被引量:11
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作者 王岚 杨继周 +8 位作者 蒋美红 段俊杰 卢叶 敖金成 马彦清 李继飞 王涛 林楠 邓国宾 《Agricultural Science & Technology》 CAS 2012年第1期139-142,共4页
[Objective] To compare the regional differences of the conventional chemi- cal compositions in the K326 B2F tobacco from different tobacco-planting areas of Yunnan Province. [Methed] Continuous flow analyzer was used ... [Objective] To compare the regional differences of the conventional chemi- cal compositions in the K326 B2F tobacco from different tobacco-planting areas of Yunnan Province. [Methed] Continuous flow analyzer was used to detect the con- ventional chemical compositions, and SPSS 17.0 statistical package was used to conduct data statistical analysis and variance analysis. [Result] Significant differences were existed among most of the indicators for conventional chemical compositions of K326 tobacco in different areas: the differences of total sugar, reducing sugar and nicotine reached a high Significant level; potassium ion and total nitrogen differences reached a significant level, while there was no significant difference in chlorine ion. Most of the conventional chemical compositions in K326 B2F tabacco planted in Yuxi region and those planted in Qujing, Dali and Chuxiong were significantly different. The total sugar, reducing sugar and nicotine contents of tobacco planted in eastern Yunnan, central Yunnan and western Yunnan were significantly different; while the conventional chemical compositions contents in the tobacco planted in Chuxiong and Dali, which all belong to western Yunnan, showed no obvious significant difference, indicating different ecological environments in large area had a great impact on the tobacco of Yunnan Province. [Conclusion] It revealed the regional characteristics of the conventional chemical compositions in K326 flue-cured tobacco leaves from Yunnan Province, providing references for the cigarette blending and production of high-quality tobacco with characteristics. 展开更多
关键词 K326 B2F Conventional chemical compositions DIFFERENCE
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Effect of Chemical Compositions on Temperature Susceptibility of Bitumens
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作者 梁永胜 余剑英 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第4期669-673,共5页
The viscosity of five bitumens was measured at different temperatures and the viscosity-temperature relationship was developed to evaluate the temperature susceptibility of different bitumens. The generic fractions (... The viscosity of five bitumens was measured at different temperatures and the viscosity-temperature relationship was developed to evaluate the temperature susceptibility of different bitumens. The generic fractions (i e, saturates, aromatics, resins and asphaltenes) of the bitumens were separated and tested by thin-layer chromatography with flame ionization detection (TLC-FID) and the effect of chemical compositions on temperature susceptibility of bitumens was analyzed using the linear regression method. The experimental results show that the four generic fractions play an inconsistent role in the temperature susceptibility of bitumens and the correlation degree of each fraction is somewhat different. The existence of aromatics and asphaltenes can lower the sensitivity to temperature changes whereas saturates and resins may have an adverse impact on the temperature susceptibility of bitumens. As for the correlation degrees, resins show the closest correlation with the temperature susceptibility of bitumens, then asphaltenes and aromatics, and the correlation between temperature susceptibility and saturates is relatively weak. 展开更多
关键词 BITUMEN temperature susceptibility chemical compositions VISCOSITY
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Liquefaction and Product Identification of Main Chemical Compositions of Wood in Phenol 被引量:14
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作者 Zhang Qiu-hui Zhao Guang-jie Jie Shu-jun 《Forestry Studies in China》 CAS 2005年第2期31-37,共7页
To clarify liquefaction ratios and their construction variations of the main chemical compositions of wood in phenol using phosphoric acid as a catalyst, the chemical ingredients of wood such as holocellulose, cellulo... To clarify liquefaction ratios and their construction variations of the main chemical compositions of wood in phenol using phosphoric acid as a catalyst, the chemical ingredients of wood such as holocellulose, cellulose and lignin, were measured and extracted according to GB methods. With Fourier transform infrared (FTIR), the product identification of reactant before and after liquefaction in phenol was investigated. The molecular weights and their distributions of the liquefaction results (acetone soluble parts) were studied by gel permeation chromatography (GPC). Results show that the molecular weights and their distributions of poplar and Chinese fir are almost the same. In poplar, the distribution of cellulose is the largest, and that ofholocellulose the smallest after liquefaction. For Chinese fir, the distribution of holocellulose is the largest, and that of cellulose the smallest. After liquefaction of poplar cellulose, the change bands of FTIR spectrum observed below 1 600 cm^-1, can be attributed to new substitute groups. The same is true for poplar lignin. For Chinese fir, the spectra of liquefaction results of all chemical compositions differ from that of wood meal. This reveals the more activity groups were produced because of the reactions between Chinese fir and phenol. The research shows that the liquefaction ratios of poplar decrease in the following order: holocellulose 〉 lignin 〉 cellulose, and those of Chinese fir in the order: lignin 〉 cellulose 〉 holocellulose. 展开更多
关键词 wood liquefaction in phenol residue ratio chemical composition FTIR GPC
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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:5
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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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Optimization model coupling both chemical compositions and high-temperature characteristics of sintering materials for sintering burden 被引量:4
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作者 Ke-jiang Li Jian-liang Zhang +3 位作者 Zheng-jian Liu Bu-xin Su Ling-tan Kong Tian-jun Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2014年第3期216-224,共9页
We developed a mathematical optimization model coupling chemical compositions and high-temperature characteristics of sintering materials, targeting the best quality and lowest cost. The simplex algorithm was adopted ... We developed a mathematical optimization model coupling chemical compositions and high-temperature characteristics of sintering materials, targeting the best quality and lowest cost. The simplex algorithm was adopted to solve this model. Four kinds of imported iron ores, two kinds of Chinese iron ore concentrates, and two kinds of fluxes were selected to verify both the model and the algorithm. The results confirmed the possibility of considering both chemical compositions and high-temperature characteristics of iron ores in the optimization model. This model provides a technical roadmap to obtain a precise mathematical correlation between the lowest cost and the grade of iron in sinters based on the condition of given raw materials, which can provide a reference to adjust the grade of iron in the sintering process for enterprise. 展开更多
关键词 SINTERING BURDEN OPTIMIZATION simplex algorithm chemical composition high temperature properies
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Metabolic rates and biochemical compositions of Apostichopus japonicus (Selenka) tissue during periods of inactivity 被引量:5
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作者 包杰 董双林 +3 位作者 田相利 王芳 高勤峰 董云伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第2期218-223,共6页
Estivation, hibernation, and starvation are indispensable inactive states of sea cucumbers Apostichopusjaponicus in nature and in culture ponds. Generally, temperature is the principal factor that induces estivation o... Estivation, hibernation, and starvation are indispensable inactive states of sea cucumbers Apostichopusjaponicus in nature and in culture ponds. Generally, temperature is the principal factor that induces estivation or hibernation in the sea cucumber. The present study provided insight into the physiological adaptations ofA. japonicus during the three types of inactivity (hibernation, estivation, and starvation) by measuring the oxygen consumption rates (Vo2) and biochemical compositions under laboratory conditions of low (3℃), normal (17℃) and high (24℃) temperature. The results show that the characteristics of A. japonicus in dormancy (hibernation and estivation) states were quite different from higher animals, such as fishes, amphibians, reptiles, and mammals, but more closely resembled a semi-dormant state. It was observed that the shift in the A. japonicus physiological state from normal to dormancy was a chronic rather than acute process, indicated by the gradual depression of metabolic rate. While metabolic rates declined 44.9% for the estivation group and 71.7% for the hibernation group, relative to initial rates, during the 36 d culture period, metabolic rates were not maintained at constant levels during these states. The metabolic depression processes for sea cucumbers in hibernation and estivation appeared to be a passive and an active metabolic suppression, respectively. In contrast, the metabolic rates (128.904-11.70 μg/g h) of estivating sea cucumbers were notably higher (107.85±6.31 μg/gh) than in starving sea cucumbers at 17℃, which indicated that the dormancy mechanism here, as a physiological inhibition, was not as efficient as in higher animals. Finally, the principle metabolic substrate or energy source of sea cucumbers in hibernation was lipid, whereas in estivation they mainly consumed protein in the early times and both protein and lipid thereafter. 展开更多
关键词 Apostichopus japonicus oxygen consumption rates chemical composition temperature periods of inactivity
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Chemical compositions and source apportionment of atmospheric PM_(10) in suburban area of Changsha, China 被引量:2
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作者 李剑东 邓启红 +1 位作者 路婵 黄柏良 《Journal of Central South University》 SCIE EI CAS 2010年第3期509-515,共7页
Source apportionment of particulate matters with aerodynamic diameter less than 10 μm (PM10) was conducted in the suburban area of Changsha, China. PM10 samples for 24 h collected with TEOM 1400a and ACCU system in... Source apportionment of particulate matters with aerodynamic diameter less than 10 μm (PM10) was conducted in the suburban area of Changsha, China. PM10 samples for 24 h collected with TEOM 1400a and ACCU system in July and October 2008 were chemically analyzed by the wavelength dispersive X-ray fluorescence (WD-XRF). Source appointment was implemented by the principal component analysis/absolute principal component analysis (PCA/APCA) to identify the possible sources and to quantify the contributions of the sources to PM10. Results show that as the PM10 concentration is increased from (85.6±43.7) μg/m3 in July 2008 to (107.6±35.7) μg/m^3 in October 2008, the concentrations of the anthropogenic elements (P, S, C1, K, Mn, Ni, Cu, Zn, and Pb) are basically increased but concentrations of the natural elements (Na, Mg, Al, Si, Ca, Ti, and Fe) are essentially decreased. Six main sources of PM10 are identified in the suburban of Changsha, China: soil dust, secondary aerosols, domestic oil combustion, waste incineration, traffic emission, and industrial emission contribute 57.7%, 24.0%, 9.8%, 5.0%, 2.0%, and 1.5%, respectively. Soil dust and secondary aerosols are the two major sources of particulate air pollution in suburban area of Changsha, China, so effective measures should be taken to control these two particulate pollutants. 展开更多
关键词 particulate matters PM10 chemical composition receptor modeling principal component analysis suburban particulate matters PM10 chemical composition receptor modeling principal component analysis SUBURBAN
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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 pr... 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 fioatation, 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 and biological activities of Flos lonicerae 被引量:2
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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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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 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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Patterns of variation in chemical compositions of wood from natural populations of Pinus manssoniana Lamb.in Guizhou Province,China
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作者 ZHAO Yang LI Yu-pu WANG Qiong 《Forestry Studies in China》 CAS 2012年第2期112-117,共6页
Patterns of variation in the chemical composition of wood, i.e., holocellulose, cellulose and lignin contents and 1% NaOH extractives were studied in 12 natural populations of Pinus manssoniana Lamb. in Guizhou Provin... Patterns of variation in the chemical composition of wood, i.e., holocellulose, cellulose and lignin contents and 1% NaOH extractives were studied in 12 natural populations of Pinus manssoniana Lamb. in Guizhou Province, China, using wood cores as experiment material. The results show statistically significant differences among provenances in holocellulose, cellulose and 1% NaOH extractive contents. The largest coefficient of variation among the provenances was found in the 1% NaOH extractive content and the smallest in the holocellulose content. Variation of lignin content occurred within provenances. Correlations between chemi- cal compositions of wood and factors of local geography and meteorology were largely insignificant. The chemical composition of wood presented patterns of random variation. The correlation of 1% NaOH extractive content with holocellulose content was sig- nificant (r = -0.68). There was also significantly negative correlation (r = -0.62) between cellulose and lignin content. On the basis of a UPGMA cluster analysis, we identified three provenances of masson pine among the 12 studied, i.e., those of Wengan, Tongzi and Luodian with high cellulose contents, low levels of 1% NaOH extractive and moderate lignin contents, which we recommend as promising provenances for growing of pulp wood and the manufacture of paper in Guizhou Province. 展开更多
关键词 Pinus manssoniana Lamb. natural population chemical composition of wood geographic genetic variation
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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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Association between Long-Term Exposure to PM_(2.5) Inorganic Chemical Compositions and Cardiopulmonary Mortality: A 22-Year Cohort Study in Northern China
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作者 Hongyue Sun Xi Chen +15 位作者 Wenzhong Huang Jing Wei Xueli Yang Anqi Shan Liwen Zhang Honglu Zhang Jiayu He Chengjie Pan Jingjing Li Jing Wu Tong Wang Jie Chen Yuming Guo Shilu Tong Guanghui Dong Nai-Jun Tang 《Environment & Health》 2024年第8期530-540,共11页
Particulate matter with diameters≤2.5μm(PM_(2.5))has been identified as a significant air pollutant contributing to premature mortality.Nevertheless,the specific compositions within PM_(2.5) that play the most cruci... Particulate matter with diameters≤2.5μm(PM_(2.5))has been identified as a significant air pollutant contributing to premature mortality.Nevertheless,the specific compositions within PM_(2.5) that play the most crucial role remain unclear,especially in areas with high pollution concentrations.This study aims to investigate the individual and joint mortality risks associated with PM_(2.5) inorganic chemical compositions and identify primary contributors.In 1998,we conducted a prospective cohort study in four northern Chinese cities(Tianjin,Shenyang,Taiyuan,and Rizhao).Satellite-based machine learning models calculated PM_(2.5) inorganic chemical compositions,including sulfate(SO_(4)^(2–)),nitrate(NO_(3)^(–)),ammonium(NH_(4)^(+)),and chloride(Cl^(-)).A time-varying Cox proportional hazards model was applied to analyze associations between these compositions and cardiorespiratory mortality,encompassing nonaccidental causes,cardiovascular diseases(CVDs),nonmalignant respiratory diseases(RDs),and lung cancer.The quantile-based g-computation model evaluated joint exposure effects and relative contributions of the compositions.Stratified analysis was used to identify vulnerable subpopulations.During 785,807 person-years of follow-up,5812(15.5%)deaths occurred from nonaccidental causes,including 2932(7.8%)from all CVDs,479(1.3%)from nonmalignant RDs,and 552(1.4%)from lung cancer.Every interquartile range(IQR)increase in SO_(4)^(2–)was associated with mortality from nonaccidental causes(hazard ratio:1.860;95%confidence interval:1.809,1.911),CVDs(1.909;1.836,1.985),nonmalignant RDs(2.178;1.975,2.403),and lung cancer(1.773;1.624,1.937).In the joint exposure model,a simultaneous rise of one IQR in all four compositions increased the risk of cardiorespiratory mortality by at least 36.3%,with long-term exposure to SO_(4)^(2–)contributing the most to nonaccidental and cardiopulmonary deaths.Individuals with higher incomes and lower education levels were found to be more vulnerable.Long-term exposure to higher levels of PM_(2.5) inorganic compositions was associated with significantly increased cardiopulmonary mortality,with SO_(4)^(2–)potentially being the primary contributor.These findings offer insights into how PM_(2.5) sources impact health,aiding the development of more effective governance measures. 展开更多
关键词 PM_(2.5)inorganic chemical compositions MORTALITY cohort study cardiorespiratory disease joint association
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Aerosol scattering coefficients and major chemical compositions of fine particles observed at a rural site in the central Pearl River Delta,South China 被引量:25
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作者 Xinming Wang Xiang Ding +5 位作者 Xiaoxin Fu Quanfu He Shaoyi Wang Francois Bernard Xiuying Zhao Dui Wu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第1期72-77,共6页
During November–December 2010 aerosol scattering coefficients were monitored using a single-waved (525 nm) Nephelometer at a regional monitoring station in the central Pearl River Delta region and 24-hr fine partic... During November–December 2010 aerosol scattering coefficients were monitored using a single-waved (525 nm) Nephelometer at a regional monitoring station in the central Pearl River Delta region and 24-hr fine particle (PM 2.5) samples were also collected during the period using quartz filters for the analysis of major chemical components including organic carbon (OC),elemental carbon (EC),sulfate,nitrate and ammonium.In average,these five components accounted for about 85% of PM 2.5 mass and contributed 42% (OC),19% (SO 4 2 -),12% (NO 3 -),8.4% (NH 4+) and 3.7% (EC),to PM 2.5 mass.A relatively higher mass scattering efficiency of 5.3 m 2/g was obtained for fine particles based on the linear regression between scattering coefficients and PM 2.5 mass concentrations.Chemical extinction budget based on IMPROVE approach revealed that ammonium sulfate,particulate organic matter,ammonium nitrate and EC in average contributed about 32%,28%,20% and 6% to the light extinction coefficients,respectively. 展开更多
关键词 scattering coefficients VISIBILITY fine particle (PM 2.5) chemical compositions
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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:3
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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),PM10(particulate matter with an aerodynamic diameter less than 10 μm) and PM2.5(particulate matter with an aerodynamic diameter l... To compare the inorganic chemical compositions of TSP(total suspended paniculate),PM10(particulate matter with an aerodynamic diameter less than 10 μm) and PM2.5(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-,Ca2+ and Mg2+ were higher in Dalian due to the influence of marine aerosol,construction activities and soil dust.The NO3-/SO42- 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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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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