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
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
[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
[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
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
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
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
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
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
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
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
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
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
[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
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
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
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
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
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
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
基金the National Natural Science Foundation of China (30460083)the Key Science and Technology Project of Chinese Ministry of Education (205164)~~
文摘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.
基金supported by National Nature Science Foundation of China(81973284)Scientific Research Foundation of the Education Department of Liaoning Province(LJKZ0944).
文摘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.
基金Supported by the Speical Fund for Agro-Scientific Research in the Public Interest(201003063)~~
文摘[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.
基金Supported by the Science and Technology Project of Yunnan Reascend Tobacco Technology(Group)Co.,Ltd.(2010RS06)the Science and Technology Project of China Tobacco Yunnan Industrial Co.,Ltd.(2008YL07,2009YL02-2)the Science and Technology Project of HONGYUNHONGHE Tobacco(Group)Co.,Ltd.,(YHH2010-YL02,YHH2010YL04)~~
文摘[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.
基金Funded by the National Natural Science Foundation of China (50773061)Self-determined and Innovative Research Funds of WUT
文摘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.
基金Supported by the Key Research Program Foundation, Ministry of Educational of China (Grant No.02021)the National Natural Science Foundation of China (Grant No. 30471351)
文摘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.
基金jointly by the National Natural Science Foundation of China(41862007 and 41402072)Yunnan Ten Thousand Talents Plan Young&Elite Talents Project(No.YNWR-QNBJ-2018-093)+2 种基金the Key Disciplines Construction of Kunming University of Science and Technology(No.14078384)the Analysis and Testing Foundation of Kunming University of Science and Technology(2017T20160006)We are grateful to Dr.Jianping Liu,Dr.Weikang Chen,and Dr.Shaoqing Liu(School of Geosciences and Info-physics,Central South University)for sulfides EPMA analyses:and Dr.Yuedong Liu,Dr.Cheng Luo.Dr.Xiaoqing Liu and Dr.Zaizao Li(Yunnan Diqin Mining Industry Group)for their field work.The authors would also like to thank anonymous reviewers for their useful comments and constructive reviews,which significantly improved the manuscript.
文摘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.
基金financially supported by the National Natural Science Foundation of China and Baosteel Group Co., Ltd., of Shanghai (U1260202)the Postdoctoral Science Foundation of China (2012T50045)
文摘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.
基金Supported by the National Natural Science Foundation of China (No.30400333)the National Key Program of Science and Technology of China (2006BAD09A01)
文摘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.
基金Project (FANEDD 200545) supported by the Foundation for the Author of National Excellent Doctoral Dissertation of China Project (50408019) supported by the National Natural Science Foundation of China Project (2008BAJ12B03) supported by National Key Project of Scientific and Technical Supporting Programs of China
文摘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.
基金supported by the key project for Science and Technology of Hubei Provincial Department of Education(No.D20101606)the Scientific and Technological Project of China Textile Industry Association(No.2008085)
文摘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.
基金This work was financially supported by National Nature Science Foundation of China(81973284)Scientific Research Foundation of the Education Department of Liaoning Province(LJKZ0944)College Student Innovation and Entrepreneurship Project of Shenyang Pharmaceutical University(202210163151).
文摘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.
基金supported by the National Key Research and Development Project of China(2021YFD1600101)the earmarked fund for China Agriculture research system(CARS-12 and CARS-13)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2021-OCRI).
文摘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.
基金Supported by Guangxi Science and Technology Research Project(Guikegong1346008-4)Guangxi Natural Science Foundation Project(2014GXNSFA A118271)
文摘[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.
基金supported by the project of Guizhou Province Agricultural Science&Technology(No.2010-3062)the project of important Science&Technology Specific Project of Guizhou Province
文摘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.
文摘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.
基金National Key Research and Development Program of China(Grants 2017YFC0211605 and 2017YFC0211704).
文摘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.
基金supported by the National Natural Science Foundation of China (No. 40821003,41025012)NSFC-Guangdong Joint Funds (No. U0833003)+1 种基金the Natural Science Foundation of Guangdong (No. 7118013)the Bureau of Science,Technology and Information of Guangzhou (No. 2010U1-E00601-2)
文摘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.
基金supported by the National Natural Science Foundation of China(No.41175111)
文摘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.
基金supported by National Nature Science Foundation of China (81973284)Scientific Research Foundation of the Education Department of Liaoning Province (LJKZ0944).
文摘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.