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Chemical Constituents and Antitumor Activities of Walnut Green Husk 预览
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作者 Fulin YAN Tiantian YIN 《药用植物研究(英文版)》 2019年第2期17-20,24共5页
[Objectives] To identify chemical constituents and antitumor activities of walnut green husk.[Methods] The column chromatography and recrystallization were used to isolate 13 compounds from walnut green husk, and thei... [Objectives] To identify chemical constituents and antitumor activities of walnut green husk.[Methods] The column chromatography and recrystallization were used to isolate 13 compounds from walnut green husk, and their structures were identified by modern spectroscopy.[Results] The 13 kinds of compounds isolated from walnut green husk were identified as 3, 5-dimethoxy-4-hydroxy benzene carbonic-7-O-β-D-pyranglucose(1), myricananin F(2),β-stitosterol(3), oleanolic acid(4), regiolone(5), asiatic acid(6), hederagenin(7),β-daucosterin(8),(4 R)-4,8-dihydroxy-α-tetralone-4-O-β-D-glucopyranoside(9), 3β, 23-dihydroxy-urs-12-en-28-oic acid(10), ursolic acid(11), syringc acid(12), and Juglanoside B(13). Among these, compounds 1, 2, 6, 7, 9, and 10 were all isolated from this genus of plant for the first time.[Conclusions] Through screening for antitumor activity in vitro, it was found that compound 4 showed strong growth inhibitory activity against the proliferation of human hepatoma cells(HepG-2), and compound 9 had certain growth inhibitory activity against the proliferation of human breast cancer cells(MCF-7). 展开更多
关键词 WALNUT green husk JUGLANDACEAE CHEMICAL constituents ANTITUMOR ACTIVITIES
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International textile city, a trip to unusual fashion 2019 Keqiao Textile Expo (Spring), Shaoxing, China, 2019 S/S Keqiao Fashion Week came to a successful end 预览
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《中国纺织:英文版》 2019年第5期28-31,共4页
Two major industrial activities in Keqiao District, Shaoxing, Zhejiang Province, 2019 Keqiao Textile Expo (Spring), Shaoxing, China, 2019SS Keqiao Fashion Week, successfully concluded 0^1 May 8th at the Inter-national... Two major industrial activities in Keqiao District, Shaoxing, Zhejiang Province, 2019 Keqiao Textile Expo (Spring), Shaoxing, China, 2019SS Keqiao Fashion Week, successfully concluded 0^1 May 8th at the Inter-national Convention & Exhibition Center of Keqiao China Textile City. Over the past four days, the worlds exhibitors, experts and scholars, in-dustry elites and other professionals gathered in Keqiao, industry linkage, wisdom linkage, creative linkage, sharing the prosperity of the textile city, creating textile city fashion, planning textile future. 展开更多
关键词 INTERNATIONAL TEXTILE city activities
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New ent-kaurane diterpenes with chiral epoxyangelate moieties from Wedelia prostrata
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作者 Zhongnan Wu Yubo Zhang +7 位作者 Wen Li Nenghua Chen Qianwen Niu Yingying Li Qingguo Li Dan Yang Yaolan Li Guocai Wang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期451-453,共3页
Four new ent-kaurane diterpenes with chiral epoxyangelate moieties, (2′R,3′R)-3 a- (2′,3′-epoxyangeloyloxy)-kaur-16-en-19-oic acid (1), (2′S,3′S)-3 a- (2′,3′-epoxyangeloyloxy)-kaur-16-en-19-oic acid (2), (2′... Four new ent-kaurane diterpenes with chiral epoxyangelate moieties, (2′R,3′R)-3 a- (2′,3′-epoxyangeloyloxy)-kaur-16-en-19-oic acid (1), (2′S,3′S)-3 a- (2′,3′-epoxyangeloyloxy)-kaur-16-en-19-oic acid (2), (2′S,3′R)-3 a- (2’,3’-epoxyangeloyloxy)-kaur-16-en-19-oic acid (3) and (2′R,3′S)-3α- (2′,3’-epoxyangeloyloxy)-kaur-16-en-19-oic acid (4), along with eight known diterpenes (5-12), were isolated from Wedelia prostrata. The absolute configurations of the new structures were determined by X-ray crystallography,ECD calculations and chemical methods. All compounds were evaluated for their cytotoxicity activities on human HepG-2 cells,with IC50 values of 11.72 ±0.22 μmol/L to 54.75±1.12 μmol/L. 展开更多
关键词 Wedelia prostrata CHIRAL epoxyangelate MOIETIES ENT-KAURANE DITERPENES ABSOLUTE configuration CYTOTOXICITY activities
A Historical Sedimentary Record of Mercury in a Shallow Eutrophic Lake: Impacts of Human Activities and Climate Change 预览
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作者 Hanxiao Zhang Shouliang Huo +3 位作者 Kevin M. Yeager Beidou Xi Jingtian Zhang Fengchang Wu 《工程(英文)》 2019年第2期296-304,共9页
Mercury and its derivatives are hazardous environmental pollutants and could affect the aquatic ecosystems and human health by biomagnification. Lake sediments can provide important historical information regarding ch... Mercury and its derivatives are hazardous environmental pollutants and could affect the aquatic ecosystems and human health by biomagnification. Lake sediments can provide important historical information regarding changes in pollution levels and thus trace anthropogenic or natural influences. This research investigates the 100-year history of mercury (Hg) deposition in sediments from Chao Lake, a shallow eutrophic lake in China. The results indicate that the Hg deposition history can be separated into three stages (pre-1960s, 1960s–1980s, and post-1980s) over the last 100 years. Before the 1960s, Hg concentrations in the sediment cores varied little and had no spatial difference. Since the 1960s, the concentration of Hg began to increase gradually, and showed a higher concentration of contamination in the western half of the lake region than in the eastern half of the lake region due to all kinds of centralized human-input sources. The influences of anthropogenic factors and hydrological change are revealed by analyzing correlations between Hg and heavy metals (Fe, Co, Cr, Cu, Mn, Pb, and Zn), stable carbon and nitrogen isotopes (d13C and d15N), nutrients, particle sizes, and meteorological factors. The results show that Hg pollution intensified after the 1960s, mainly due to hydrological change, rapid regional development and urbanization, and the proliferation of anthropogenic Hg sources. Furthermore, the temperature, wind speed, and evaporation are found to interactively influence the environmental behaviors and environmental fate of Hg. 展开更多
关键词 Lake sediment MERCURY Vertical distribution ANTHROPOGENIC activities
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Diel and seasonal patterns of variation in the singing behaviour of Savannah Sparrows(Passerculus sandwichensis) 预览
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作者 Ines G.Moran Katrina C.Lukianchuk +4 位作者 Stephanie.M.Doucet Amy E.M.Newman Heather Williams D.Ryan Norris Daniel J.Mennill 《鸟类学研究:英文版》 CSCD 2019年第3期336-343,共8页
Background:The vocalizations of birds are dynamic traits that often vary in output with time of day and time of year.By quantifying patterns of diel and seasonal variation in vocal output,we can gain insight into the ... Background:The vocalizations of birds are dynamic traits that often vary in output with time of day and time of year.By quantifying patterns of diel and seasonal variation in vocal output,we can gain insight into the ecology and evolution of birds and the function of their vocalizations.In this investigation,we quantified diel and seasonal variation in song output by studying a breeding population of Savannah Sparrows (Passerculus sandwichensis).Methods:We used autonomous recorders to collect extensive recordings across the breeding season in a long-term, colour-marked study population of Savannah Sparrows in eastern Canada.We described diel and seasonal variation across five different breeding stages based on recordings of more than 50,000 songs from 34 males.Results:During the pre-breeding stage, prior to female arrival, males sang a pronounced dawn chorus with a peak in song output during the early morning.During the breeding stage,in contrast,the dawn chorus was diminished and males instead exhibited a pronounced dusk chorus with a peak in song output during the evening.Across the breeding season,the highest levels of song output occurred in late April and early May,soon after males arrived on the breeding grounds,and the lowest levels occurred in August,prior to the departure of birds for the wintering grounds.Conclusions:These patterns suggest that Savannah Sparrows' early-season dawn choruses are directed at males and serve a territorial defense function.Later-season dusk choruses,in contrast, appear to play a role in attracting mates and possibly acoustic mate guarding. 展开更多
关键词 Bird SONG Breeding activities Circadian RHYTHMS Seasonal VARIATION in SONG
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Pharmacokinetic evaluation,molecular docking and in vitro biological evaluation of 1,3,4-oxadiazole derivatives as potent antioxidants and STAT3 inhibitors 预览
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作者 Rashmin khanam Iram I. Hejazi +2 位作者 Syed Shahabuddin Abdul R. Bhat Fareeda Athar 《药物分析学报:英文版》 CAS CSCD 2019年第2期133-141,共9页
1,3,4-Oxadiazole derivatives (4a–5f) were previously synthesized to investigate their anticancer properties.However,studies relating to their antioxidant potential and signal transducer and activator of transcription... 1,3,4-Oxadiazole derivatives (4a–5f) were previously synthesized to investigate their anticancer properties.However,studies relating to their antioxidant potential and signal transducer and activator of transcription (STAT) inhibition have not been performed.We investigated previously synthesized 1,3,4-oxadiazole derivatives (4a–5f) for various radical scavenging properties using several in vitro antioxidant assays and also for direct inhibition of STAT3 through molecular docking.The data obtained from various antioxidant assays such as 2,2,-diphenyl-1-picrylhydrazyl radical (DPPH),nitric oxide,hydrogen peroxide,and superoxide anion radical revealed that among all the derivatives,compound 5e displayed high antioxidant activities than the standard antioxidant L-ascorbic acid.Additionally,the total reduction assay and antioxidant capacity assay further confirmed the antioxidant potential of compound 5e.Furthermore,the molecular docking studies performed for all derivatives along with the standard inhibitor STX-0119 showed that binding energy released in direct binding with the SH2 domain of STAT3 was the highest for compound 5e (-9.91kcal/mol).Through virtual screening,compound 5e was found to exhibit optimum competency in inhibiting STAT3 activity.Compound 5e decreased the activation of STAT3 as observed with Western blot.In brief,compound 5e was identified as a potent antioxidant agent and STAT3 inhibitor and effective agent for cancer treatment. 展开更多
关键词 1 3 4-oxadiazoles STRUCTURE-ACTIVITY relationship (SAR) Antioxidant activities STAT3 INHIBITORS Molecular DOCKING
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To what extent is CLT applicable to the Chinese teaching context? 预览
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作者 Zha Min 《校园英语》 2019年第40期160-161,共2页
Chinese people all know that English is very important for the future development of China.What is the goal for learning a foreign language?It is for communication,but not for taking examinations.However,most of the t... Chinese people all know that English is very important for the future development of China.What is the goal for learning a foreign language?It is for communication,but not for taking examinations.However,most of the time in class are taken up by teaching grammar points instead of giving them opportunities to communicate.A lot of Chinese teachers notice that,so CLT is frequently used in class these years.This essay aims to argue that,to some extent,CLT is applicable to Chinese teaching context.In the following paragraphs,I will analyze the goal of using CLT for Chinese teachers in the first and second paragraphs.In the third and fourth paragraph,I will mainly refer to the characteristics of CLT process.The fifth and sixth paragraphs illustrate and emphasize the benefits students can get from Communicative Language Teaching. 展开更多
关键词 COMMUNICATIVE LANGUAGE TEACHING COMMUNICATIVE ACTIVITIES interaction MOTIVATE
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Redox-responsive ferrocene-containing poly(ionic liquid)s for antibacterial applications
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作者 Tikai Zhang Jiangna Guo +2 位作者 Yingying Ding Hailei Mao Feng Yan 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第1期95-104,共10页
Ferrocene(Fc)-containing imidazolium type ionic liquids(ILs) and corresponding poly(ionic liquid)(PIL) membranes with tunable antibacterial activity based on electrochemical redox reaction and host-guest chemistry wer... Ferrocene(Fc)-containing imidazolium type ionic liquids(ILs) and corresponding poly(ionic liquid)(PIL) membranes with tunable antibacterial activity based on electrochemical redox reaction and host-guest chemistry were developed. The effect of Fc moiety on the antimicrobial activities against both Staphylococcus aureus(S. aureus) and Escherichia coli(E. coli) was studied by minimum inhibitory concentration(MIC). The presence of Fc groups highly enhanced the antibacterial efficiency of Fccontaining ILs because of the generation of reactive oxygen species(ROS). The electrochemical oxidation of Fc to Fc+and the formation of inclusion complexes between Fc and β-CD via host-guest interactions decreased the antibacterial activities of ILs and PIL membranes. The antibacterial activities may be recovered in some extent upon the electrochemical reduction of Fc+to Fc or the exclusion of the Fc out of the cavity of β-CD. Furthermore, all the Fc-containing PIL membranes showed relatively low hemolysis activities and none cytotoxicity toward human cells, indicating clinical feasibility in topical applications. 展开更多
关键词 ANTIBACTERIAL activities IMIDAZOLIUM CATIONS FERROCENE poly(ionic liquid) cytotoxicity
Coastal Environmental Changes and Management in China in the Context of Global Changes and Human Activities 预览
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作者 Yunfeng ZHANG Yingying CHEN +2 位作者 Xiaobin HUA Shiqing YAN Lili ZOU 《亚洲农业研究:英文版》 2019年第7期24-30,33共8页
Coastal zone is the complex area with intense sea-land interaction. There are various types, complex environments and developed economy in coastal area of China. Under the influence of global change and human activiti... Coastal zone is the complex area with intense sea-land interaction. There are various types, complex environments and developed economy in coastal area of China. Under the influence of global change and human activities, the ecosystem of coastal zone is vulnerable and has sensitive response to environment changes. The environmental problems of sea-level rising have attached close attention by countries all over the world. As far as regions concerned, relative sea-level rising is more important than theoretical sea-level rising. The relative sea-level rising has resulted in series of environment disasters in coastal area of China, such as coastal erosion, seawater invasion, and floods in coastal lowlands, etc. The flux of sediments transported by rivers into sea is the main material source of marine pollution. The human activities are controlling factors of variations in river sediment loads. Under the influence of high strength development in the upstream region, the results are that the reduction of seagoing sediments in main rivers of China, and damage of coastal material balance. Land-based pollution is the main source of marine pollution. With rapid economic development in China s eastern coastal, pollutants flux into sea increase gradually. The results are that the environmental quality and seawater quality of marine have being deteriorated and pollution is serious increasingly. To meet the land demand of industrialization and urbanization, the sea reclamation has become an effective means to alleviate the contradiction between human and land in coastal area of China. This leads to large-scale reduction of coastal wetland area, and the heavy losses of ecological service value of coastal wetland. To face the environmental changes in coastal area of China and solve the contradiction among population, resources, environment, development, it is required to set up the system concept of man-land-sea relationship, so as to achieve sustainable development. The feasible measures include improving coastal management s 展开更多
关键词 Costal areas ENVIRONMENTAL changes Human ACTIVITIES Integrated management
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Synthesis of Novel Chalcone Derivatives by Organic Catalysis 预览
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作者 Junlong Li Ruocan Zhuang Yinan Qian 《材料物理与化学》 2019年第1期50-56,共7页
Chalcone compounds have a wide range of biological activities. In this paper, nine kinds of novel chalcone compounds were synthesized by using transacrylone derivatives and anthrone as raw materials. The eff ects of d... Chalcone compounds have a wide range of biological activities. In this paper, nine kinds of novel chalcone compounds were synthesized by using transacrylone derivatives and anthrone as raw materials. The eff ects of diff erent catalysts and solvents on the yield of the products were investigated. The optimal catalyst was DABCO. The optimum solvent was dichloromethane with the highest yield of 71.6%. On this basis, the eff ect of the co - catalyst on the yield was investigated. The yield was increased to 89.9%. 展开更多
关键词 CHALCONE ACTIVITIES BASIS
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完善基于教育信息化的大学英语第二课堂 预览
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作者 张月珍 《丽水学院学报》 2019年第4期119-123,共5页
随着高等教育信息化的不断推进,现代信息技术与传统英语教学逐渐深度融合。本文首先指出教育信息化背景下大学英语第二课堂面临的机遇,接着提出了在信息化背景下大学英语第二课堂遭遇的困难——教学资源库建设有待完善、活动形式有待创... 随着高等教育信息化的不断推进,现代信息技术与传统英语教学逐渐深度融合。本文首先指出教育信息化背景下大学英语第二课堂面临的机遇,接着提出了在信息化背景下大学英语第二课堂遭遇的困难——教学资源库建设有待完善、活动形式有待创新和学习效果实时监测困难,最后提出了具体的解决方案。以期为学生提供更好的英语第二课堂学习环境,培养学生自主学习能力,树立学生自主学习意识,实现大学英语教学效果和人才培养质量的提升。 展开更多
关键词 教育信息化 大学英语第二课堂 教学资源库 活动形式 学习效果监测
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Does Rapid Urbanization Trigger Significant Increase of Cumulative Heavy Rains in China? 预览
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作者 Feng KONG 《亚洲农业研究:英文版》 2019年第6期25-32,共8页
Severe disasters caused by extreme precipitation events have attracted more and more attention. The relationship between climate change and extreme precipitation has become the hottest scientific frontier issue. The s... Severe disasters caused by extreme precipitation events have attracted more and more attention. The relationship between climate change and extreme precipitation has become the hottest scientific frontier issue. The study of daily torrential rain observations from 659 meteorological stations in China from 1951 to 2010 shows that rapid urbanization may have triggered a significant increase in heavy rains in China. It reached following conclusions: China’s interdecadal heavy rainfall amount,rainy days and rain intensity increased significantly,with an increase of 68. 71%,60. 15% and 11. 52%,respectively. The increase in the number of stations was 84. 22%,84. 22% and 54. 48%,respectively. It showed time change of " rapid-slow-rapid increase" and spatial change of gradual increase from southeastern coast to central China,southwest,north China,and northeastern regions. Rapid urbanization factors,including secondary industry output( GDP2),urban population ratio( UP),annual average haze days( HD),are likely to be the main causes of the increase in heavy rains in China. Their explanations of the variance of heavy rainfall amount( HRA),rainy day( RD) and rain intensity( RI) in China reached 61. 54%,58. 48% and 65. 54%,respectively,of which only the explanation of variance of heavy rainfall amount,rainy days and rain intensity was as high as 25. 93%,22. 98%and 26. 64%,respectively. However,explanation of variance of climatic factors including WPSH( West Pacific Subtropical High),ENSO( El Ni1 o-Southern Oscillation) AMO( Atlantic Interdecadal Oscillation),and AAO( Antarctic Oscillation) was only 24. 30%,26. 23%,and 21. 92%,respectively. Compared with the rapid urbanization forcing factor,the impact of these climatic factors was only one third of the former. The panel data of China’s county-level total population and annual average of visibility days were significantly correlated with China’s interdecadal heavy rainfall amount,rainy days and rain intensity. Their spatial correlation coefficient increased gradually from 展开更多
关键词 CUMULATIVE heavy RAIN Human activities URBANIZATION TRIGGERING factors Spatial and temporal pattern China
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Agricultural Risk Factors Influence Microbial Ecology in Honghu Lake
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作者 Maozhen Han Melissa Dsouza +9 位作者 Chunyu Zhou Hongjun Li Junqian Zhang Chaoyun Chen Qi Yao Chaofang Zhong Hao Zhou Jack A Gilbert Zhi Wang Kang Ning 《基因组蛋白质组与生物信息学报:英文版》 CAS CSCD 2019年第1期76-90,共15页
Agricultural activities,including stock-farming,planting industry,and fish aquaculture,can affect the physicochemical and biological characters of freshwater lakes.However,the effects of pollution producing by agricul... Agricultural activities,including stock-farming,planting industry,and fish aquaculture,can affect the physicochemical and biological characters of freshwater lakes.However,the effects of pollution producing by agricultural activities on microbial ecosystem of lakes remain unclear.Hence,in this work,we selected Honghu Lake as a typical lake that is influenced by agriculture activities.We collected water and sediment samples from 18 sites,which span a wide range of areas from impacted and less-impacted areas.We performed a geospatial analysis on the composition of microbial communities associated with physicochemical properties and antibiotic pollution of samples.The co-occurrence networks of water and sediment were also built and analyzed.Our results showed that the microbial communities of impacted and less-impacted samples of water were largely driven by the concentrations of TN,TP,NO3-N,and NO[-N,while those of sediment were affected by the concentrations of Sed-OM and Sed-TN.Antibiotics have also played important roles in shaping these microbial communities:the concentrations of oxytetracycline and tetracycline clearly reflected the variance in taxonomic diversity and predicted functional diversity between impacted and less-impacted sites in water and sediment samples,respectively.Furthermore,for samples from both water and sediment,large differences of network topology structures between impacted and less-impacted were also observed.Our results provide compelling evidence that the microbial community can be used as a sentinel of eutrophication and antibiotics pollution risk associated with agricultural activity;and that proper monitoring of this environment is vital to maintain a sustainable environment in Honghu Lake. 展开更多
关键词 FRESHWATER MICROBIAL COMMUNITIES Agriculture activities ANTIBIOTICS Human impact
如何激发幼儿学习舞蹈的兴趣 预览
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作者 杨海燕 《教育教学论坛》 2019年第43期256-257,共2页
舞蹈对于幼儿来说仿佛是那甜蜜而又诱人的糖,是幼儿表达自己内心的主要形式,展现了幼儿的天真无邪。因此在幼儿园教育中激发幼儿学习舞蹈的兴趣,对于幼儿的身心发展、性格塑造有非常重要的作用。幼儿是那纯洁无瑕的白纸,文章结合自己多... 舞蹈对于幼儿来说仿佛是那甜蜜而又诱人的糖,是幼儿表达自己内心的主要形式,展现了幼儿的天真无邪。因此在幼儿园教育中激发幼儿学习舞蹈的兴趣,对于幼儿的身心发展、性格塑造有非常重要的作用。幼儿是那纯洁无瑕的白纸,文章结合自己多年的教学经验,浅谈如何激发幼儿学习舞蹈的兴趣,以及如何让幼儿学好舞蹈。 展开更多
关键词 幼儿 舞蹈 学习兴趣 活动
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Synthesis and insecticidal bioactivities of 2,3-dihydroimidazo[1,2-a] pyridin-5(1H)-one derivatives
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作者 Letian Zhang Kun Liu +2 位作者 Xusheng Shao Zhong Li Xiaoyong Xu 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期340-344,共5页
A novel synthesis of 2,3-dihydroimidazo[1,2-a]pyridin-5 (1H)-one 4 and its derivatives were described.Preliminary bioassays showed that some of the target compounds exhibited excellent insecticidal activities against ... A novel synthesis of 2,3-dihydroimidazo[1,2-a]pyridin-5 (1H)-one 4 and its derivatives were described.Preliminary bioassays showed that some of the target compounds exhibited excellent insecticidal activities against brown planthopper (Nilaparvata lugens), cowpea aphids (Aphis craccivora) (4,5 a, 5 c, 5 g,5 h, 5 j, 5 r, 6 b, 6 e) and carmine spider mite (Tetranychus cinnabarinus (5 f, 5 s, 6 a) at 500 mg/L. Among them,compound 4 was still active against brown planthopper and cowpea aphids at 4 mg/L. The insecticidal activities were influenced by the types and position of the substituents, which provided guidance for the structure modifications. 展开更多
关键词 Reaction selectivity 2 3-Dihydroimidazo[1 2-a]pyridin-5(1H)one Bicyclic pyridone INSECTICIDAL activities Acaricidal activitiy
海南胡椒蔓提取物活性测试及化学成分分离鉴定 预览
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作者 赵方方 韩丙军 +2 位作者 吕岱竹 谢德芳 罗金辉 《热带作物学报》 CSCD 北大核心 2019年第7期1317-1324,共8页
胡椒全株富含生物活性成分,胡椒蔓是其修枝整形后的废弃物,产量巨大,具备较大的开发利用潜力。本文研究比较了胡椒蔓和胡椒根的抗炎、抗氧化活性,结果表明,石油醚和水相提取物活性相对较差,而胡椒蔓乙酸乙酯提取物抗炎抗氧化活性最强,... 胡椒全株富含生物活性成分,胡椒蔓是其修枝整形后的废弃物,产量巨大,具备较大的开发利用潜力。本文研究比较了胡椒蔓和胡椒根的抗炎、抗氧化活性,结果表明,石油醚和水相提取物活性相对较差,而胡椒蔓乙酸乙酯提取物抗炎抗氧化活性最强,效果与胡椒根相当,具备进一步开发利用的潜力。进一步利用硅胶柱层析、凝胶层析、制备色谱等多种分离手段,得到8个化合物,通过核磁共振、质谱等手段进行鉴定,明确了其结构,包括黄酮类、甾醇类、生物碱、木质素和酸酯类等多种化合物。本研究为胡椒蔓抗炎、抗氧化活性提供了重要的化学基础,也为胡椒废弃物高值化利用提供了有效的途径和理论依据。 展开更多
关键词 胡椒蔓 废弃物 活性 抗炎 抗氧化 分离鉴定
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Synthesis and Bioactivities Evaluation of Novel Anthranilic Diamides Containing N-(tert-Butyl)benzohydrazide Moiety as Potent Ryanodine Receptor Activator
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作者 Yunyun Zhou Wei Wei +1 位作者 Liangliang Zhu Yuxin Li 《中国化学:英文版》 SCIE CAS CSCD 2019年第6期605-610,共6页
Anthranilic diamides have been proven to be a class of efficacious and safe insecticides targeting ryanodine receptors (RyRs) during the last decade. In order to develop innovative scaffolds with high insecticidal act... Anthranilic diamides have been proven to be a class of efficacious and safe insecticides targeting ryanodine receptors (RyRs) during the last decade. In order to develop innovative scaffolds with high insecticidal activity, two series of N-pyridylpyrazole derivatives containing N-(tert-butyl)benzohydrazide substructures were designed and synthesized. Their insecticidal activities against oriental armyworm (Mythimna separata) and diamondback moth (Plutella xylostella) were evaluated. Preliminary bioassay results revealed that some of the new compounds exhibited good insecticidal activity against the oriental armyworm and diamondback moth. The mode of action of these compounds were verified using calcium-imaging technique and the results showed that some new compounds could effectively modulate the insect cytosolic Ca^2+ level, and break the cellular calcium homeostasis, indicating some of these compounds were potent activators of the RyRs. 展开更多
关键词 anthranilic diamides acylhydrazine HETEROCYCLES calcium channel STRUCTURE-ACTIVITY relationships INSECTICIDAL activities
Chemical constituents and pharmacological properties of Sarcandra glabra(Thunb.)Nakai. 预览
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作者 Hao Zhang Peng Zhao +2 位作者 Yangyang Zhang Xiaoxiao Huang Shaojiang Song 《亚洲传统医药》 2019年第5期237-246,共10页
Sarcandra glabra(Thunb.)Nakai.,belonging to Chloranthaceae genus of Sarcandra family,is widely used as the common Chinese herbal medicine in folk.As a traditional medicinal agent,a wide spectrum of chemical constituen... Sarcandra glabra(Thunb.)Nakai.,belonging to Chloranthaceae genus of Sarcandra family,is widely used as the common Chinese herbal medicine in folk.As a traditional medicinal agent,a wide spectrum of chemical constituents have been isolated from the S.glabra,including sesquiterpenoids,triperpenoids,flavonoids,coumarins,phenolic acids and volatile oil.Modern pharmacological studies have shown that S.glabra has many biological activities such as anti-cancer,hepatoprotective activity,anti-inflammatory and anti-asthmatic activities.For the further development of this plant,the primary chemical constitutions of S.glabra and their activities have been summarized in this study. 展开更多
关键词 Sarcandra glabra(Thunb.)Nakai. CHEMICAL constituents PHARMACOLOGICAL ACTIVITIES REVIEW
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Green synthesis of Chlorin e6 and tests of its photosensitive bactericidal activities 预览
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作者 Guocai Zhang Jing Yang +6 位作者 Chunping Hu Xiucheng Zhang Xiao Li Shan Gao Xiao Ouyang Ning Ma Hao Wei 《林业研究:英文版》 CAS CSCD 2019年第6期2349-2356,共8页
Phototoxic treatments of pathogenic bacteria and fungi of trees induce oxidative damage that is preferable to toxic chemical treatment.Here,we used green methods to synthesize Chlorin e6 from chlorophyll a,which was e... Phototoxic treatments of pathogenic bacteria and fungi of trees induce oxidative damage that is preferable to toxic chemical treatment.Here,we used green methods to synthesize Chlorin e6 from chlorophyll a,which was extracted from crude silkworm excrement using concentrated(strong)alkali hydrolysis and acidification.The photosensitive bactericidal activities of the new chlorin were tested in vitro,and possible mechanisms of action are discussed.The results showed that Chlorin e6 can be lightactivated to have bactericidal activity against Escherichia coli,Bacillus subtilis and Fusarium oxysporum,but it had little bactericidal effect in the dark.This kind of chlorin compounds has great potential as a natural phototoxic antimicrobial compound to control harmful bacteria on the leaves in forestry systems. 展开更多
关键词 CHLORIN E6 PHOTOSENSITIVE BACTERICIDAL ACTIVITIES
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A cultivated area forecasting approach in artificial oases under climate change and human activities 预览
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作者 ZHANG Shaobo CHEN Fulong +3 位作者 CHEN Jie WANG Jing LI Shaofei LONG Aihua 《干旱区科学:英文版》 SCIE CSCD 2019年第3期400-418,共19页
The cultivated area in artificial oases is deeply influenced by global climate change and human activities.Thus,forecasting cultivated area in artificial oases under climate change and human activities is of great sig... The cultivated area in artificial oases is deeply influenced by global climate change and human activities.Thus,forecasting cultivated area in artificial oases under climate change and human activities is of great significance.In this study,an approach named GD-HM-PSWROAM,consisting of general circulation model downscaling(GD),hydrological model(HM),and planting structure and water resource optimal allocation model(PSWROAM),was developed and applied in the irrigation district of the Manas River Basin in Xinjiang Uygur Autonomous Region of China to forecast the cultivated area tendency.Furthermore,the catchment export of the MIKE11 HD/NAM model was set to the Kensiwate hydrological station.The results show that the downscaling effects of temperature can be fairly satisfying,while those of precipitation may be not satisfying but acceptable.Simulation capacity of the MIKE11 HD/NAM model on the discharge in the Kensiwate hydrological station can meet the requirements of running the PSWROAM.The accuracy of the PSWROAM indicated that this model can perform well in predicting the change of cultivated area at the decadal scale.The cultivated area in the Manas River Basin under current human activities may be generally decreasing due to the climate change.But the adverse effects of climate change can be weakened or even eliminated through positive human activities.The cultivated area in the Manas River Basin may even be increasing under assumed human activities and future climate scenarios.The effects of human activities in the future can be generally predicted and quantified according to the cultivated area trends under current human activities and the situations in the study area.Overall,it is rational and acceptable to forecast the cultivated area tendency in artificial oases under future climate change and human activities through the GD-HM-PSWROAM approach. 展开更多
关键词 GCM DOWNSCALING HYDROLOGICAL model CULTIVATED area climate change human activities MANAS River Basin
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