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A Sparse Autoencoder Based Denosing the Spectrum Signal in LIBS

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A Sparse Autoencoder Based Denosing the Spectrum Signal in L...

New Diterpenoid Alkaloids from Delphinium Souliei Franch

第30届中国控制与决策会议

作者： Shibing Ye Zhixing Niu Peng Yang Junqing Sun Tianjin Key Laboratory of Intelligence Computing and Novel Software Technology Tianjin University of Technology

Based on laser induced breakdown spectroscopy（LIBS） technique, the content of the main elements in the liquid steel of carbon steel alloy can be detected in real time during melting process. In order to detect the liquid alloy steel and forecast the content of the main elements in the alloy steel more accurately, we use the method of sparse autoencoder to reduce noise in the spectral data which were collected in the detecting process. The experimental results show that the sparse autoencoder method can effectively improve the accuracy and precision of the spectral data.

关键词： LIBS sparse autoencoder spectral data denosing

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Chinese Chemical Letters 1999年第5期10卷 395-396页

作者： Lan HE Yuan Jiang PAN Xuan PAN Bo Gang LI Yao Zu CHEN(Department of Chemistry. Beijing Normal University. Beijing 100085 Department of Chemistry. Zhejiang University. Hangzhou 310027Department of Pharmcy. Lanzhou Medical College. Lanzhou 730000The Che Department of Chemistry Beijing Normal University Beijing 100085 China Department of Chemistry Zhejiang University Hangzhou 310027 China Department of Pharmcy Lanzhou Medical College Lanzhou 730000 China Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 China

Continuing investigation of Delphinium souliei Franch yielded two minor new diterpenoid alkaloids--souline E(1) and souline F(2), their structures were determined on the basis of spectroscopic evidences.

关键词： Delphinium souliei new deterpenoid alkaloids souline E and F spectral data

Studies on the amide compounds ofMirabilis. Jalapa. L

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Chemical Research in Chinese Universities 2001年第z1期17卷 38-39页

作者： SHEN XuWei College of chemistry and Chemical Engineering Northwest Normal University

Mirabilis himalaica(Edgew.)Heinerl Var. Chinensis Heimerl belonging to the genus Mirabilis are used in chinese medicine as a remedy for various diseases[1].Its chemical constituents,however, have not been reported so far. we have carried out a detailed chemical investigatigation of the seeds and have isolated two new amides along with three known compounds.The known compounds were identified by comparing their spectral data with those of authentic samples or with those reported in literature as daucosterol[2], bsitoserol[2], boeravinone E[3], in the present note, the structural elucidation of two new amides is reported.

关键词： structural elucidation chemical constituents chinese medicine spectral data used in

Novel Reaction of Some Azoles with Dimethyl Sulfoxid

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有机化学 2004年第z1期24卷 146-页

作者： WANG,Bin ZHU,An-Xiong DONG,Heng-Shan College of Science and Engineering Gansu Association University Lanzhou 730000 Jinchang Agriculture Middle School Gansu 737100 State Key Laboratory of Applied Organic Chemistry Institute of Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

　　The compounds 4a～4j were prepared by 3a～3j which were prepared from 1a～1j through 2a～2j. The compounds 6a～6j were prepared by the reaction of the products of 4a～4j with dimethyl sulfoxid via Dimroth rearrangement.[1] The compounds ethyl 5-arylamino-1H-1,2,3-triazol-4-carbonates (5a～5d) and ethyl 2-methylthiamethylene-5-arylamino-2H-1,2,3-triazol-4-carbonates (6a～6j) are established by MS, IR, elemental analysis and 1H NMR spectral data. The route of syntheses is shown in Scheme 1.……

关键词： spectral data

Isolation and Identification of Flavonoids Found in Zostera marina Collected in Norwegian Coastal Waters

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American Journal of Plant Sciences 2016年第7期7卷 1163-1172页

作者： Kjersti Hasle Enerstvedt Monica Jordheim Øyvind M. Andersen Department of Chemistry University of Bergen Bergen Norway

In extracts of the seagrass Zostera marina, collected in coastal waters of West-Norway, fourteen different flavones and high amounts of rosmarinic acid were identified. Five of the flavones were found to be sulphated, among these were luteolin 7,3'-disulphate and chrysoeriol 7-sulphate structures previously not published with complete NMR assignments. Luteolin 7-O-β-(6''-malonyl) glucoside, and two other malonylated flavone compounds occurring in trace amounts, were identified for the first time in Z. marina. The sulphated flavones were fairly stable in slightly acidified (0.1% trifluoroacetic acid) extracts stored for months, however, under more acidic conditions (0.5% trifluoroacetic acid in the extracts) they were susceptible to undergo hydrolyses. When the solvents of purified fractions were removed by rotary evaporation, the sulphated flavones quickly decomposed to their corresponding aglycones due to the increased acid concentrations.

关键词： Zostera marina Sulphated Flavones NMR spectral data Characterization Stability

Study on Roots of Firmiana plantanifolia (L.f.) Marsili

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有机化学 2004年第z1期24卷 384-页

作者： BAI,Hai-Yun LI,Shuo HU,Li-Hong National Center for Drug Screening Shanghai Institute of Materia Medica Shanghai 201203 National Center for Drug Screening Shanghai Institute of Materia Medica Shanghai 201203 National Center for Drug Screening Shanghai Institute of Materia Medica Shanghai 201203

　　Firmiana plantanifolia (L.f.) Marsili is a Chinese medicine used in the treatment of numerous disorders such as rheumatism, asthma, fracture, and tumor etc.[1] In the course of a search for biological active compounds from medicinal plants,[2] we have examined the water extract of the root of this plant and succeeded in isolating three novel constituents named firmianones A, B and C (Scheme 1), along with 9 known compounds. Their UV, HRMS and NMR spectral data indicated that they are isoprenylated naphthoquinone dimmers. Firmianones A and B have a novel hexacyclo [14.***.0.02,7.***.15.099.14.018,23]tetracosa-1(16),3,9(14),10,12,7,19,21,23-nonaen-8-one skeleton and their absolute stereochemistry was determined by CD exciton-coupling experiments.……

关键词： medicinal plants Chinese medicine water extract spectral data used in

Utilization of Landsat data for Quantifying and Predicting Land Cover Change in the Bumbuna Watershed in Sierra Leone

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Natural Resources 2016年第9期7卷 495-504页

作者： Abubakarr Mansaray Abdulai Barrie Bumbuna Watershed Management Authority Bumbuna Sierra Leone

Rural communities in third world countries are concerned over land use changes resulting from resource exploitation. This is the case for the Bumbuna watershed in Sierra Leone following impoundment of the Bumbuna reservoir in 2009. Farmers have increased activities along the riparian zones in protest against inundation of their farmlands. The dam operators warn this practice would threaten sustainable power supply;the farmers contend the reservoir is increasing and taking over their farms. However, it is difficult to resolve this issue without a means of quantifying the change and developing early warning systems for land cover in the watershed. This research presents a case for the use of remotely sensed Landsat data for quantification of land cover change and the development of predictive models to inform preparedness for imminent problems that may arise from land use practices. In situ water loggers, in combination with manual readings, recorded water levels in 30-minute intervals since 2009. These datasets combined with spectral values of Landsat 7 and Landsat 8 for the development of regression algorithms for predictive purposes. Digital photographs and satellite imagery illustrated the changes in land cover over time (a 33% water rise and 44% NDVI change from 2009 to 2015). These visual and spectral pictures confirm the usefulness of remotely sensed data for early warning systems in the watershed. Results of the regression analysis show Band 1 (Blue) and Band 4 (NIR) as statistically significant predictors for water level in the reservoir. The tests accounted for 84% (R2) of the data with p-values less than α at the 0.05 confidence level. However, future trials of the model will consider reducing the 4.6 error margin to minimize deviations from the observed data.

关键词： Watershed Hydroelectric Power Farming Water Loggers Landsat Remote Sensing spectral data

Synthesis of 3- [ 1- (4-Ethoxyphenyl)-5-methyl-1,2,3-triazol-4-yl ]-6- substituted- s-triazolo [ 3,4- b ] -1,3,4-thiadiazoles

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有机化学 2003年第Z1期23卷 427-427页

作者： DONG Heng-Shan WANG Bin National Laboratory of Applied Organic Chemistry Institute of Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 National Laboratory of Applied Organic Chemistry Institute of Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

　　Several 3- [ 1- (4-ethoxyphenyl)-5-methyl- 1,2, 3-triazol-4-yl ]-6-substituted-s-triazolo [ 3,4- b ]- 1,3,4-thiadia zoles have been synthesized and the structures of these compounds were established by MS, IR and ... 详细信息

关键词： spectral data

Synthesis and Structure Elucidation of Celangulin Derivatives

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有机化学 2004年第z1期24卷 302-页

作者： ZHANG,Ji-Wen WU,Wen-Jun TIAN,Xuan Institute of Pesticide Science Northwest Sci-Tech University of Agriculture and Forest Yangling 712100 College of Life Science Northwest Sci-Tech University of Agriculture and Forest Yangling 712100 Institute of Pesticide Science Northwest Sci-Tech University of Agriculture and Forest Yangling 712100 National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000

　　Celangulins are sesquiterpene polyol esters based on a core structure known as β-dihydroagarofuran from Celastrus angulatus Max. Some of them are environment acceptable-pesticides. In order to find new active compounds and study their SAR, sesquiterpene polyol esters libraries were synthesized based on the basic hydrolysis of the extract of the root bark of Celastrus angulatus which could offer the β-dihydroagarofuran polyol by combinatorial chemical method and the compounds with insecticidal activity were isolated by bioassay-guided fractionation. Two new compounds with insecticidal activity against Mythimna separata, were isolated and elucidated as 2β,6α,8β, 13-tetraisobutanoyloxy-1β,4,9α-trihydroxy-β-dihydroagarofuran (A) and 1β,2β,6α,8β, 13-pentaisobutanoyloxy-4α,9α-dihydroxy-β-dihydroagarofuran (B) mainly by 1H NMR, 13C NMRH-HCOSY, HMQC, HMBC and HRMS spectral data. A: [α]20D -7.3 (c 0.12, CHCl3), B: [α]20D -34.6 (c 0.8,CHCl3).……

关键词： insecticidal activity Celastrus angulatus chemical method core structure spectral data root bark