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Journal of Environmental Sciences 2012年第1期24卷 72-77页

作者： Xinming Wang Xiang Ding Xiaoxin Fu Quanfu He Shaoyi Wang Francois Bernard Xiuying Zhao Dui Wu State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Guangzhou 510640China Graduate University of Chinese Academy of Sciences Beijing 100049China Guangzhou Environmental Monitoring Center Guangzhou 510030China Institute of Tropical and Marine Meteorology China Meteorological AgencyGuangzhou 510080China

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 *** 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 *** 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.

关键词： scattering coefficients visibility fine particle (PM 2.5) chemical compositions

chemical compositions of Volatile Oil from Fruiting Body of Armillaria luteo-virens

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Agricultural Science & Technology 2008年第2期9卷 90-92页

作者：周劲松熊辉岩杨春江焦迎春盛海彦浙江建设职业技术学院浙江杭州311231 青海大学青海西宁810016

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.

关键词： Armillaria luteo-rirens Volatile oil chemical compositions GC-MS

Effect of chemical compositions on Temperature Susceptibility of Bitumens

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Journal of Wuhan University of Technology(Materials Science) 2010年第4期25卷 669-673页

作者：梁永胜余剑英 Key Laboratory of Silicate Materials Science and Engineering of Education Ministry Wuhan University of Technology Inner Mongolia High-grade High Way Construction and Development Co. Ltd

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.

关键词： bitumen temperature susceptibility chemical compositions viscosity

A Comparative Study on chemical compositions of Hippophae rhamnoides *** and *** form China

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A Comparative Study on Chemical Compositions of Hippophae rh...

Effects of nitrogen concentrations on the growth and chemical compositions of Phaeodactylum tricornutum

第七届全国系统与进化植物学青年学术研讨会

作者： TIAN Chun-Jie, NAN Peng, TANG Xiao-Shu, LEI Yi-Don , CHEN Jia-Kuan, ZHONG Yang (Institute of Biodiversity Sciences, Fudan University, Shanghai 200433, China)

The inter-population variability of chemical composition of Hippophae rhamnoides subsp. yunnanensis and subsp. sinensis from fourteen populations in China were analysed by GC-MS. 45 compounds are represented and ident... 详细信息

关键词： Hippophae rhamnoides chemical compositions

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Effects of nitrogen concentrations on the growth and chemica...

Spatial and Temporal Variability of PM2.5 chemical compositions and Characteristics of Pollution Episodes in Guanzhong Plain

中国海洋湖沼学会藻类学分会第七届会员大会暨第十四次学术讨论会

作者： Cai Zhuoping Duan Shunshan(Institute of Hydrobiology,Jinan University Guangzhou 510632,China)

Marine diatom Phaeodactylum tricornutum is a phytoplankton species that has been served as an important food source or feed additive in the rearing of aquatic animals like shrimp and *** recent years,however,occurrences of red tides due to the over proliferation of this microalga along the coast of Hainan province and Shangdong province have been reported,which potentially devastated the aquaculture around and destroyed the natural marine ecosystems,with a tremendous economic *** the other hand,nitrogen,an essential element for plant growth,has been believed to be one of the most important,nutritional factors regulating the growth and metabolism of ***,relatively scarce information is available concerning the growth and chemical compositions of this alga in response to nitrogen concentrations,standing on the viewpoint that Phaeodactylum tricornutum may be a red tide-causative marine microalga in recent *** order to reveal the effects of different nitrogen concentrations on the growth and some chemical compositions in Phaeodactylum tricornutum,algal cell density,biomass,soluble sugar,protein and chlorophyll a were investigated in laboratory cultures by employing low nitrogen(LN,44 μM NaNO),medium nitrogen(MN,880μM NaNO)and high nitrogen(HN, 4400 μM NaNO)*** results indicated that cell density,specific growth rate and cell biomass of Phaeodactylum tricornutum were increased obviously with the increasing of N *** were 149.50×10 ***,0.37 d,and 209.33 μ*** LN condition,whereas they were 951.67×10 ***,0.67 d,and 806.00 μ***,under HN condition at the 10day during the stationary ***,the contents of soluble sugar, protein and chlorophyll a were significantly affected by different nitrogen concentrations,which were approximately 2.5,1.5 and 15 times respectively higher in HN treatment than those in LN *** can be concluded from the present study that high nitrogen concentration can accel

关键词： nitrogen concentrations growth chemical compositions Phaeodactylum tricornutum

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Spatial and Temporal Variability of PM2.5 Chemical Compositi...

chemical composition,pharmacological activity and development strategies of Rubus chingii:A review

第八届全国大气细及超细粒子技术研讨会暨PM_(2.5)源谱交流会

作者： Xinyi Niu Junji Cao Zhenxing Shen Hongmei Xu Ting Zhang Rong Zhang School of Human Settlements and Civil Engineering Xi'an Jiaotong University Key Lab of Aerosol Chemistry & Physics Institute of Earth Environment Chinese Academy of Sciences Institute of Global Environmental Change Xi'an Jiaotong University Department of Environmental Science and Engineering Xi'an Jiaotong University

Particulate matter pollution is a serious environmental problem which influencing air quality,regional and global climates,and humanhealth in *** year of fine aerosol samples(PM) were collected at Guanzhong Plain with six sampling sites in different cities from March2012 to *** 24-h average mass concentration of PM was 134.7μg/m,which was high enough to raise serious concerns over the air quality in Guanzhong *** of the six sites exhibited highest OC and EC values in winter,and EC levels always varied with OC concentrations and the variabilityin OC was *** contributions of secondary species SO,NO and NH in total ions were greatest,and the high concentrations in winter were mainly due to emissions from coalcombustion and biomass *** autumn the haze days were severest in Xi’an city with similar tendency of PMvariations,and it was proved that biomass burning was the main emission source of the regional *** winter pollution episodes,the pollution patterns in Guanzhong Plain are similar which were resulted from strong secondary reactions and coal *** addition,mitigating primary particulate emissions including incomplete combustion of coal andbiomass,engine exhaust,and fugitive dust,reducing the emissionsof secondary aerosol precursors including SO,NO,and NH are both importantfor reducing the environmental,economic and health impacts from PM pollutions.

关键词： Guanzhong Plain PM2.5 chemical compositions Pollution episode

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Chinese Herbal Medicines 2024年第3期16卷 313-326页

作者： Xiangmei Xiong Zheng Liu Xiance Che Xuemin Zhang Xia Li Wenyuan Gao Tianjin University of Traditional Chinese Medicine Tianjin 301600China Tianjin Key Laboratory for Modern Drug Delivery&High-Efficiency School of Pharmaceutical Science and TechnologyFaculty of MedicineTianjin UniversityTianjin 300110China Key Laboratory of Advanced Chinese Medicine Resources Research Enterprises Tianjin 300402China

Raspberries are used for both food and medicine,but it has not yet attracted widespread *** this paper,the chemical constituen of the original plant *** is one of the new“Zhe Bawei”medicinal materials selected in 2017.“Zhe Bawei”refers to eight kinds of genuine medicinal materials in Zhejiang *** chemical constituents,pharmacological effects,processing,and application of Rubus chingii Hu were reviewed to provide a reference for its further *** literature in recent years was collected in databases such as China Knowledge Network,Web of Science,Elsevier,PubMed,and X-Mol,using“raspberry”,“Rubus chingii”,“traditional use”,“chemical composition”,“pharmacology”,*** keywords individually or in *** summary of pharmacological activities shows that the relationship between the pharmacological activities of raspberry is still not deep *** in-depth research should be carried out in this direction to explore the mechanism of action of its active ingredients and provide effective reference for the further development of the raspberry *** the future,with the participation of more researchers,it is expected to develop innovative drugs based on raspberry for the treatment of diseases.

关键词： applications chemical compositions processing pharmacological effects Rubus chingii Hu

Effect of Stabilizers and Storage Time on the Quality of Tomato Sauce

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Journal of Environmental Science and Engineering(A) 2024年第1期13卷 27-35页

作者： Kouch Sothakong Hor Rathna Ek Sopheap THENG Kouch Chay Chim Faculty of Agro-industry Royal University of AgriculturePhnom Penh 12400Cambodia Faculty of Veterinary Medicine Royal University of AgriculturePhnom Penh 12400Cambodia Ministry of Agriculture Forestry and Fisheries Phnom Penh 12300Cambodia

The experiment was conducted at laboratory of the faculty of Agro-industry,Royal University of Agriculture,locating in Phnom Penh city,commenced from August to October,*** single factor CRD(Completely Randomized Design)was used with 6 treatments and 3 *** the 7 ingredients were used such as tomato,sugar,salt,onion,bell pepper,sodium benzoate and vinegar,with or without *** processing,the sauce was kept in room temperature to observe the self-life and the variation of nutrients contain in 8 *** chemical compositions in the sauce were analyzed to identify the variation during storing in the temperature *** the findings showed that the pH value,Total soluble solids and Color(L,A&B)of all treatments has decreased in 8th week comparing to starting point,while the Total acids *** comparing among the 6 treatments,after the products have produced(w0),all the chemical compositions in group T0 containing the lowest,exception of Fat and Color(L).When the self-life up to eight weeks,all the composition parameters were statistically different(except for Moisture,Ash,Dry Mass,and Fat).For identification the Bacteria presenting showed that there was no present in first day of self-life until the first *** present of bacteria were detected from 2nd week to 8th week,excepted *** CFU of T0 had the lowest number of colonies,while T3 had the highest *** the same time,we found that the number of colonies decreases with the age of storage(self-life),which means that at the beginning of growing in the second week,it had higher amount(from 2.10 to 2.69 of CFU as log);while this number decreased with the shelf life up to 8 weeks,which is between 0 to 2.35.

关键词： Self-life chemical compositions bacteria CFU.

chemical constituents and pharmacological effects of Croton crassifolius

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Asian Journal of Traditional Medicines 2024年第2期19卷 99-114页

作者： Luyan Yang Yibo Wang Xinyao Wang Xiaoxia Xu Yunpeng Yang Meng Zhang Yu Chen School of Life Science and Biopharmaceutics Shenyang Pharmaceutical UniversityShenyang 110016China School of Business Liaoning UniversityShenyang 110136China

Croton crassifolius(CC)is a kind of traditional Chinese medicine rich in terpenoids,with among which diterpene species are the *** had biological activities in the treatment of cancer,inflammation,ulcerative colitis,osteoporosis and Alzheimer’s *** study reviews the chemical compositions and pharmacological activities of CC to provide reference for further research.

关键词： Croton crassifolius chemical compositions pharmacological activities

Heavy haze pollution during the COVID-19 lockdown in the Beijing-Tianjin-Hebei region,China

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Journal of Environmental Sciences 2022年第4期34卷 170-178页

作者： Xin Zhang Zhongzhi Zhang Zhisheng Xiao Guigang Tang Hong Li Rui Gao Xu Dao Yeyao Wang Wenxing Wang Environment Research Institute Shandong UniversityQingdao 266237China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China China National Environmental Monitoring Centre Beijing 100012China

To investigate the characteristics of particulate matter with an aerodynamic diameter less than 2.5μm(PM_(2.5))and its chemical compositions in the Beijing-Tianjin-Hebei(BTH)region of China during the novel coronavirus disease(COVID-19)lockdown,the ground-based data of PM_(2.5),trace gases,water-soluble inorganic ions,and organic and elemental carbon were analyzed in three typical cities(Beijing,Tianjin,and Baoding)in the BTH region of China from 5-15 February *** PM_(2.5)source apportionment was established by combining the weather research and forecasting model and comprehensive air quality model with extensions(WRF-CAMx).The results showed that the maximum daily PM_(2.5)concentration reached the heavy pollution level(>150μg/m^(3))in the above three *** sum concentration of SO_(4)^(2-),NO_(3)^(-)and NH_(4)^(+)played a dominant position in PM_(2.5)chemical compositions of Beijing,Tianjin,and Baoding;secondary transformation of gaseous pollutants contributed significantly to PM_(2.5)generation,and the secondary transformation was enhanced as the increased PM_(2.5)*** results of WRF-CAMx showed obviously inter-transport of PM_(2.5)in the BTH region;the contribution of transportation source decreased significantly than previous reports in Beijing,Tianjin,and Baoding during the COVID-19 lockdown;but the contribution of industrial and residential emission sources increased significantly with the increase of PM_(2.5)concentration,and industry emission sources contributed the most to PM_(2.5)***,control policies should be devoted to reducing industrial emissions and regional joint control strategies to mitigate haze pollution.

关键词： COVID-19 lockdown Heavy haze pollution chemical compositions Source apportionment Beijing-Tianjin-Hebei region