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A research on statistical retrieval algorithms and spectral characteristics of the total absorption coefficients in the Yellow Sea and the East China Sea 被引量:4
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作者 王晓梅 唐军武 +2 位作者 宋庆君 丁静 马超飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2006年第3期236-242,共7页
This paper suggests a group of statistical algorithms for calculating the total absorption coefficients based on in situ data of apparent optical property and inherent optical property collected with strict quality as... This paper suggests a group of statistical algorithms for calculating the total absorption coefficients based on in situ data of apparent optical property and inherent optical property collected with strict quality assurance according to NASA ocean bio-optic protocols in the Yellow Sea and the East China Sea in spring 2003. The band-ratios ofRrs412/Rrs555, Rrs49o/Rrs555 are used in the algorithms to derive the total absorption coefficients (at) at 412, 440, 488, 510, 532 and 555nm bands, respectively. The average relative errors between inversed and measured values are less than 25.8%, with the correlative coefficients (R2) being 0.75-0.85. Error sensitivity analysis shows that the maximum retrieval error is less than 24.0% at +5% error in Rrs's. So the statistical algorithms of this paper are practicable. In this paper, the relations between the total absorption coefficients at 412, 488, 510, 532, 555 nm and that of 440nm are also studied. The results show that the relations between the total absorption coefficients of 400-600 nm and that of 440 nm are correlated well and all of their correlative coefficients R2 are greater than 0.99. Furthermore, a regression analysis is also done for the slope of the linear relations and wavelengths, and the R2 is also 0.99. Thus it is possible to retrieve other bands' total absorption coefficients with only one band absorption value, which significantly reduce the number of unknown parameters in studying other ocean color related problems. 展开更多
关键词 Case-II water algorithms the total absorption coefficient statistical model
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FIRST LANGUAGE ACQUISITION AS A MODEL FOR SECOND LANGUAGE ACQUISITION: THE TOTAL PHYSICAL RESPONSE APPROACH IN SECOND LANGUAGE LEARNING AND TEACHING 被引量:11
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作者 井卫华 《外语与外语教学》 1988年第2期12-22,共11页
L1 and L2 acquisition, in some respects, are similar. Language development in children goes hand in hand with physical and cognitive development. Children learn their first language by imitation, but not always and no... L1 and L2 acquisition, in some respects, are similar. Language development in children goes hand in hand with physical and cognitive development. Children learn their first language by imitation, but not always and not only by imitation. There seems to be some "innate capacities" that make children start to speak at the same time they do and in the way they do it. Adults learning a second language usually are controlled more by their motivation. But language input is important for both L1 and L2 acquisition. Though there are differences between CL1 and between CL2 and AL2, the way in which these learners acquire some of the grammatical morphemes is similar. This, together with some other evidence, shows that it is not only children who can acquire language. Adults can also acquire a language. But when adults acquire a language, they should also learn it. Some of the ways in which children acquire their language can be used as a model for L2 acquisition, even for Chinese students whose language is unrelated to English and whose culture is different. Learning the culture of the English-speaking countries will benefit the learning of the language. Like children, listening should also be well in advance of speaking in L2 acquisition. To train listening comprehension skills, Asher’s TPR approach proves more effective. TPR approach is at the moment limited to the beginning stage only. In order for students to gain all the five skills in a second language learning, namely, listening, speaking, reading, writing, and interpreting/translating, other methods should be used at the same time, or at later stages. 展开更多
关键词 the total PHYSICAL RESPONSE APPROACH IN SECOND LANGUAGE LEARNING AND TEACHING FIRST LANGUAGE ACQUISITION AS A MODEL FOR SECOND LANGUAGE ACQUISITION total
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Analysis of Hupehenine in the Total Alkaloids from Fritillaria hupehensis by HPLC-ELSD 被引量:2
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作者 张鹏 李娟 +4 位作者 张国欣 皮慧芳 张勇慧 阮汉利 吴继洲 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第1期118-120,共3页
A reverse-phase high pressure liquid chromatography (HPLC) method with evaporative light scattering detection (ELSD) has been developed for the quantitative analysis of hupehenine in the total alkaloids from Friti... A reverse-phase high pressure liquid chromatography (HPLC) method with evaporative light scattering detection (ELSD) has been developed for the quantitative analysis of hupehenine in the total alkaloids from Fritillaria hupehensis. Samples were analyzed on a reverse-phase column (Hypersil C-18) with a mobile phase of methanol:water:chloroform: triethylamine (85:15:1:0.6). The ELSD was set at the drift tube temperature of 68.3℃ and gas flow rate of 1.8 L/min. Hupehenine's retention time was 13.7 min with an asymmetry factor of 1.2. The validity of the method has been verified with linearity, limit of detection, accuracy and precision. The logarithmic linear curve was obtained from 8.936 to 134.04 μg/mL (r=0.9993). The detection limit (S/N〉3) of hupehenine was 1.79 μg/mL on the column. Intra-day RSD was 1.42% and inter-day RSD was 2.26% (3 days within a week). The average recovery of hupehenine was 101.50%, and RSD was 1.62%. 展开更多
关键词 Fritillaria hupehensis the total alkaloids hupehenine high pressure liquid chromatography evaporative light scattering detection
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Chemical Analysis Method for Carbon Bearing Refractory Products——Determination of the Total Carbon by Combustion Gravimetric Method 被引量:1
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作者 Shen Keyin 《China's Refractories》 CAS 2007年第1期34-36,共3页
GB/T 13245-91 1 Theme and Scope This standard specifies the method abstract, reagents, apparatus, specimen, analyzing procedure, result calculation and permissible tolerance used for determination of the total carbon ... GB/T 13245-91 1 Theme and Scope This standard specifies the method abstract, reagents, apparatus, specimen, analyzing procedure, result calculation and permissible tolerance used for determination of the total carbon with combustion gravimetric method. 展开更多
关键词 Determination of the total Carbon by Combustion Gravimetric Method Chemical Analysis Method for Carbon Bearing Refractory Products
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THE TOTAL CONTENTS OF VOL.18(2008)
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《中国有色金属学会会刊:英文版》 CSCD 2008年第6期I0001-I0010,共10页
关键词 the total CONTENTS OF VOL.18 AI JUN De SIC VOL LI total
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The Total Synthesis of (±)-Hinesol and (±)-Agarospirol
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作者 Jin Jun WANG Chang Jin YUE Jun QIU (Department Of Fine Chemistry, Jilin Chemical Engineering College, Jilin, 132002)Cang Yi QIAN(Department of Chemistry, Qing Hua University, Beijing, 100084) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第11期957-960,共4页
A mild base-catalyzed retro-benzilic acid rearrangement of a proto-[2+2]photocycloadduct, formed in highly steroselective photoaddition of methyl 2,4-dioxo-pentanoate to 1,5-dimethyl-6-methylenecyclohexene, afforded ... A mild base-catalyzed retro-benzilic acid rearrangement of a proto-[2+2]photocycloadduct, formed in highly steroselective photoaddition of methyl 2,4-dioxo-pentanoate to 1,5-dimethyl-6-methylenecyclohexene, afforded a spiro[4, 5] decenedione from which hinesol and agarospirol were synthesized by means of reductive elimination of α-diketone and C1-homologation. 展开更多
关键词 the total Synthesis of Hinesol and Agarospirol
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Study on the Total Synthesis of 3-Oxo-9β-Acetoxyilicic Acid─The Synthesis of 9β-Acetoxy-3(4),11(13)-Dien-5αH,7αH-12-Eudesmanoic Acid Methyl Ester
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作者 Jiong YANG Zbao Ming XIONG Yong Gang CREN and Yu Lin LI(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,ho University, Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
The synthesis of 99-acetoxy-3(4), 11(13)-dien-5αH 7αH-12-eudesmanoic acid methyl ester (2) was achieved from oxycarvone. The key step is the p-toluenesulfonhydrazide assisted reductiv rearrangement reaction
关键词 the Synthesis of 9 H 7 H-12-Eudesmanoic Acid Methyl Ester Dien-5 Study on the total Synthesis of 3-Oxo-9 Acetoxyilicic Acid Acetoxy-3
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THE TOTAL CONTENTS OF VOL.17 (2007)
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《中国有色金属学会会刊:英文版》 CSCD 2007年第6期M0004-M0013,共10页
关键词 PING VOL the total CONTENTS OF VOL.17 total SIC
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Studies on the Total Synthesis of Hainanolide(Ⅳ)-Revising the Stereochemistry of C_(2α)-H and Introducing the Two Hydroxy Groups at C_(3β),C_(4α) Positions
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作者 Wen Qian YANG Xiao Ming YU +1 位作者 Shi Zhi CHEN Liang HUANG(Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College,Beijing, 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
Tricyclic compound 6 was synthesized form compound 1 through sis steps, thus preblem of the stereochemistry of C2α-H being solved. The stereochemistry for introducing hydroxy groups at C3β and C4α positions in com... Tricyclic compound 6 was synthesized form compound 1 through sis steps, thus preblem of the stereochemistry of C2α-H being solved. The stereochemistry for introducing hydroxy groups at C3β and C4α positions in compound 1 was also described. 展开更多
关键词 Studies on the total Synthesis of Hainanolide POSITIONS Revising the Stereochemistry of C H and Introducing the Two Hydroxy Groups at C
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Study on the Total Synthesis of Hainanolide (Ⅱ)──An Unexpected Hydroperoxide Containing Tricyclic Skeleton
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作者 Lu Yan ZHANG Wen Qian YANG +1 位作者 Shi Zhi CHEN Liang HUANG(Institute of Materia Medica, Chinese Academy of Medical Sciences,Peking Union Medical College,Beijing,100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第1期15-16,共2页
An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed b... An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed by spectra and X-Ray diffraction analysis, An 1O2oxidation mechanism was proposed. 展开更多
关键词 ppm An Unexpected Hydroperoxide Containing Tricyclic Skeleton Study on the total Synthesis of Hainanolide
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THE TOTAL CONTENTS OF VOLUME 22(2012)
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《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第12期I0001-I0020,共20页
关键词 total the total CONTENTS OF VOLUME 22
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The Total Contents of Vol.19,2012
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《Journal of Central South University》 SCIE EI CAS 2012年第12期I0001-I0018,共18页
关键词 the total Contents of Vol.19 2012 JUN
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THE TOTAL CONTENTS OF VOL.19 (2009)
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《中国有色金属学会会刊:英文版》 CSCD 2009年第6期I0001-I0010,共10页
关键词 VOL the total CONTENTS OF VOL.19 total
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Studies on the Total Synthesis of Hainanolide(Ⅲ)-Unusual Diene Isomerization in a Diels-Alder Reaction
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作者 Wen Qian YANG Lu Yan ZHANG +1 位作者 Shi Zhi CHEN Liang HUANG (Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第3期203-204,共2页
An unexpected diene isomerization of the triene acid 3 in the Lewis acid catalyzed intramolecular Diels-Alder reaction was observed
关键词 Unusual Diene Isomerization in a Diels-Alder Reaction Studies on the total Synthesis of Hainanolide
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The total quality management of blood center at new stage
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《中国输血杂志》 CAS CSCD 2001年第S1期355-,共1页
关键词 the total quality management of blood center at new stage
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Identification of the Caroline Plate boundary:constraints from magnetic anomaly
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作者 Yongtao Fu Guoliang Zhang +4 位作者 Wanyin Wang An Yang Tao He Zhangguo Zhou Xiao Han 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第8期1-12,共12页
The Caroline Plate is located among the Pacific Plate,the Philippine Sea Plate,and the India Australia Plate,and plays a key role in controlling the spreading direction of the Philippine Sea Plate.The Caroline Submari... The Caroline Plate is located among the Pacific Plate,the Philippine Sea Plate,and the India Australia Plate,and plays a key role in controlling the spreading direction of the Philippine Sea Plate.The Caroline Submarine Plateau(or Caroline Ridge)and the Eauripik Rise on the south formed a remarkable T-shaped large igneous rock province,which covered the northern boundary between the Caroline Plate and the Pacific Plate.However,relationship between these tectonic units and magma evolution remains unclear.Based on magnetic data from the Earth Magnetic Anomaly Grid(2-arc-minute resolution)(V2),the normalized vertical derivative of the total horizontal derivative(NVDR-THDR)technique was used to study the boundary of the Caroline Plate.Results show that the northern boundary is a transform fault that runs 1400 km long in approximately 28 km wide along the N8°in E-W direction.The eastern boundary is an NNW-SSE trending fault zone and subduction zone with a width of tens to hundreds of kilometers;and the north of N4°is a fracture zone of dense faults.The southeastern boundary may be the Lyra Trough.The area between the southwestern part of the Caroline Plate and the Ayu Trough is occupied by a wide shear zone up to 100 km wide in nearly S-N trending in general.The Eauripik transform fault(ETF)in the center of the Caroline Plate and the fault zones in the east and west basins are mostly semi-parallel sinistral NNW-SSE–trending faults,which together with the eastern boundary Mussau Trench(MT)sinistral fault,the northern Caroline transform fault(CTF),and the southern shear zone of the western boundary,indicates the sinistral characteristics of the Caroline Plate.The Caroline hotspot erupted in the Pacific Plate near the CTF and formed the west Caroline Ridge,and then joined with the Caroline transform fault at the N8°.A large amount of magma erupted along the CTF,by which the east Caroline Ridge was formed.At the same time,a large amount of magma developed southward via the eastern branch of the ETF,forming the northern segment of the Eauripik Rise.Therefore,the magmatic activity of the T-shaped large igneous province is obviously related to the fault structure of the boundary faults between the Caroline Plate and Pacific Plate,and the active faults within the Caroline Plate. 展开更多
关键词 Caroline Plate magnetic anomaly normalized vertical derivative of the total horizontal derivative plate boundary Caroline Ridge Eauripik Rise
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The first protein ever synthesized in vitro—a personal reminiscence of the total synthesis of crystalline insulin 被引量:7
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作者 ZHANG YouShang Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences Shanghai 200031,China 《Science China(Life Sciences)》 SCIE CAS 2010年第1期16-18,共3页
The total synthesis of crystalline bovine insulin started in 1958 was fully accomplished in 1965. This formidable task was a collaboration of the Institute of Biochemistry in Shanghai,
关键词 the first protein ever synthesized in vitro a personal reminiscence of the total synthesis of crystalline insulin
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The background of the total synthesis of yeast alanine transfer RNA 被引量:6
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作者 QI GuoRong Institute of Biochemistry and Cell Biology,Shanghai Institute for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China 《Science China(Life Sciences)》 SCIE CAS 2010年第1期19-21,共3页
The research findings concerning the total synthesis of yeast alanine transfer RNA (yeast alanine tRNA) were successively published in Chinese Science Bulletin (1982) and Science
关键词 TRNA the background of the total synthesis of yeast alanine transfer RNA
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The Northern Path of Asian Dust Transport from the Gobi Desert to North America 被引量:5
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作者 Chen Ke-Yi 《Atmospheric and Oceanic Science Letters》 2010年第3期155-159,共5页
The aerosol index (AI) of the Total Ozone Mapping Spectrometer (TOMS) satellite data (1979 2001) was analyzed to reveal the climatological long-distance path of dust transport from Asia to North America. The AI in the... The aerosol index (AI) of the Total Ozone Mapping Spectrometer (TOMS) satellite data (1979 2001) was analyzed to reveal the climatological long-distance path of dust transport from Asia to North America. The AI in the west coast of the United States is highly correlated with that in the Gobi desert. Additionally, from the TOMS satellite images, it can be seen that very strong plumes advect from Asia to the west coast of North America in typical dust storm cases. When applying the sourcereceptor relationship to detect the northern dust transport path between the Gobi source region and the west coast of the United States receptor region, it is evident that the dust plume can be transported northward beyond 60°N from its source region and that it takes 5 to 6 days to reach the west coast of the United States. The cross correlation technique shown in this work is a useful tool that can be applied in other regions to give useful insights into relationships between major dust sources and downwind receptor locations by using remotely sensed dust observations. 展开更多
关键词 dust transport the total Ozone Mapping Spectrometer satellite data
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East Asian summer monsoon changes in subtropical China since late Pleistocene:Evidence from the Ailuropoda-Stegodon fauna
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作者 LI Zhi-wen SUN Li +6 位作者 LI Bao-sheng WANG Feng-nian DU Ding-ding SONG You-gui ZHANG Hui-Juan CHEN Liu-qin XU Dan 《Journal of Mountain Science》 SCIE CSCD 2022年第2期418-432,共15页
Previous studies on the amplitude of East Asian summer monsoon(EASM)changes mainly focused on northern China(represented by the Loess Plateau).However,a rare investigation centered on the subtropical zone of southern ... Previous studies on the amplitude of East Asian summer monsoon(EASM)changes mainly focused on northern China(represented by the Loess Plateau).However,a rare investigation centered on the subtropical zone of southern China,where the important route for EASM moved northward or southward,especially addressing a lack of the research on mammals.The Ailuropoda-Stegodon fauna is a representative mammal fauna in southern China since the late Pleistocene.It indicates the southern mid-subtropicaltropical forest environment with tropical climate characteristics,and its southward or northward movements in the subtropical zone imply the changes of EASM intensity.Based on previous research,combined with the species characteristics and distribution range of the Ailuropoda-Stegodon fauna with tropical animals during the marine isotope stage 5(MIS5),MIS3,MIS2,and MIS1 Megathermal periods,this paper mainly investigates its evolution and the fluctuations of EASM.The conclusions include:(1)The distribution geometric centers in the MIS5,MIS3,MIS2,and MIS1 Megathermal periods are(26°14′N,111°22′E),(24°35′N,107°30′E),(22°48′N,112°01′E),and(26°19′N,112°25′E),respectively.(2)Compared with the MIS5 period,the EASM of the MIS3 and MIS2 moved 180 km and 380 km southwards,and that of the MIS1 Megathermal period moved about 10 km northwards.The EASM movement indicated by the fauna migration happened synchronous with the climate records of stalagmites in subtropical China,the sporopollen from eastern China,and oxygen isotopes from Sulu Sea.They also correspond to the peaks and valleys of the total solar radiation at 35°N in the winter half-year.This suggests that the migrations of the Ailuropoda-Stegodon fauna are consistent with the changes of the global climate,and the driving force is mainly from the changes of total solar radiation at 35°N in the winter half-year. 展开更多
关键词 Late Pleistocene to Holocene Subtropical China the Ailuropoda-Stegodon fauna Tropical animals migration East Asian summer monsoon changes the total solar radiation
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