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Demonstration of Covalent Sidewall Functionalization of Single Wall Carbon Nanotubes by NMR Spectroscopy:Side Chain Length Dependence on the observation of the Sidewall sp^(3)Carbons

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Nano Research 2008年第1期1卷 72-88页

作者： Liling Zeng Lawrence b.Alemany Christopher L.Edwards Andrew R.barron Richard E.Smalley Institute for Nanoscale Science and Technology and Department of Chemistry Rice UniversityHoustonTX 77005USA

Carboxylic acid-functionalized single walled carbon nanotubes(SWNTs)prepared via the reaction of an amino acid,NH2(CH2)nCo2H where n=1(glycine,GLY),5(6-aminohexanoic acid,AHA),10(11-aminoundecanoic acid,AUDA),with fl uorinated single walled carbon nanotubes(F-SWNTs)have been characterized by MAS 13C NMR *** ease of observing the aliphatic CH2 groups and the resolution of the signal are dependent on the length of the amino acid’s aliphatic *** have proposed that where substituent chains are short(making NMR data collection difficult)chemical modification to extend the chain length should alleviate analysis *** this regard,we have investigated the esterifi cation of the carboxylic acid *** amino acid-functionalized SWNTs were esterified with an appropriate alcohol to ensure parity of the overall substituent length,i.e.,GLY-SWNT(C1)+1-dodecanol(C_(12))=DoD-GLY-SWNT(1),AHA-SWNT(C_(5))+1-octanol(C_(8))=oCT-AHA-SWNT(2),and AUDA-SWNT(C_(10))+1-propanol(C_(3))=PRo-AUDA-SWNT(3).The 13C NMR shift for the sp3 nitrogen-substituted carbon atoms of the SWNT sidewall is observed atδ≈75 *** the length of SWNT sidewall functional groups enhances the ability to observe the sidewall sp^(3)*** methylene carbon signal intensity is less attenuated in the dipolar dephasing spectrum of the ester-functionalized SWNTs than their associated amino acid derivatives,suggesting more motional freedom of the side chain in the solid *** confi rmation of the dipolar dephasing spectral effects was assisted by the characterization of the ester of AUDA-SWNT with 1,3-propanediol:PPD-AUDA-SWNT(4).

关键词： Single walled carbon nanotube(SWNT) nuclear magnetic resonance(NMR) esterification amino acid functionalization

Health Risks Assessment Due to Exposure to Vinyl Chloride in Groundwater from a Closed Landfill： A Case Study as a Contaminant of Concern and Effect of Subsurface Characteristics

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Journal of Environmental Science and Engineering 2010年第7期4卷 41-49页

作者： b. Sizirici b. Tansel Florida International University Civil and Environmental Engineering Department Miami 33174 Florida USA

The purpose of this study was to analyze the migration pathways of contaminants from closed landfills and to estimate health risks based on soil characteristics. The health risks were estimated using Framework for Risk Analysis Multimedia Environmental Systems （FRAMES） software. The sensitivity of human health risks and hazard indices due to vinyl chloride contamination in groundwater were performed in relation to soil characteristics such as Darcy velocity, thickness of soil layer, mass of contaminant present in the aquifer. based on the analysis, Darcy velocity showed no effect on estimated risks. Since soil layer thickness had a significant effect on the estimated health risks, effects of different soil types on estimated risks were analyzed. The results showed that soils from the least appropriate to the most appropriate for risk management due to groundwater contamination were sand, sandy clay, sandy loam, loam and clay loam. FRAMES model was suitable for assessing the health risks due to vinyl chloride contamination in groundwater originating from a municipal solid waste landfill. The model showed the changes in both carcinogenic and non carcinogenic risks over time. The estimated health risks were directly correlated with the levels of vinyl chloride detected in groundwater.

关键词： Health risk assessment FRAMES municipal solid waste landfills groundwater monitoring vinyl chloride factorial analysis.

Triterpene Glycosides from Sea Cucumber Holothuria scabra with Cytotoxic Activity

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Chinese Herbal Medicines 2012年第3期4卷 183-188页

作者： Hua HAN[a][b] Ling LI[b] Yang-hua YI[b] Xiao-hua WANG[c] Min-xiang PAN[d] College of Animal Sciences Zhejiang UniversityHangzhou 310058China Research Center for Marine Drugs School of PharmacySecond Military Medical UniversityShanghai 200433China

objective To study the new triterpene glycosides from sea cucumber Holothuria scabra with cytotoxic activity. Methods Triterpene glycosides from H. scabra were separated and purified by chromatography on DA-101, silica gel, and reversed-phase silica gel column, as well as RP-HPLC. Their structures were elucidated on the basis of spectral data and chemical evidence. Results Three triterpene glycosides were identified as scabraside D (1), fuscocineroside C (2), and 24-dehydroechinoside A (3). Their inhibition on P-388, A549, MKN-28, HCT116, and MCF-7 cells were significant. Conclusion Scabraside D (1) is a new triterpene glycoside, and compounds 2 and 3 are isolated from H. scabra for the first time. The glycosides 1-3 show the in vitro cytotoxicity against five human tumor cell lines in comparison to 10-hydroxycamptothecin.

关键词： cytotoxicity 24-dehydroechinoside A fuscocineroside C Holothuria scabra scabraside D triterpene glycoside

A NUMERICAL RESEARCH oF NoNLINEAR boDY-WAVE INTERACTIoNS

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Journal of Hydrodynamics 1991年第3期3卷 88-104页

作者： Zhou Zhen-quan Gu Mao-xiang, China Ship Scientific Research Center, P. o. box 116, Wuxi 214082, Jiangsu, P.R.China China Ship Scientific Research Cent Jiangsu China

This paper presents numerical research results of nonlinear body-wave interactions. The body-wave interac- tion is treated as a transient problem with known initial conditions. The development of the flow can be obtained by a time-stepping procedure, in which the velocity potential of the flow at any instant is obtained by utilizing a source density distribution on all boundary surfaces. The orlanski's method is used to implement the boundary con- dition at the open boundary. The position of intersection points are determined by a direct method. The contents of this paper are: (1) A study of the nonlinear radiation problem of a floating body; (2) A study of nonlinear wave diffraction problem around large structures; (3) Interaction of nonlinear waves with a free floating body; (4) An attempt in generating a numerical wave tank. Pretty good agreement is met between the numerical results and the analytical solution.

关键词： body A NUMERICAL RESEARCH oF NoNLINEAR boDY-WAVE INTERACTIoNS boDY

A Study of Protein and Glycoprotein Syntheses in Pre-implantation Mouse Embryos Using Mini-2D-Electrophoresis, Video Densitometer Scanning and Computer-Image Analysis

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Science China Chemistry 1993年第1期36卷 39-44页

作者：郑明曹詠清 b.LoftsDepartment of Zoology University of Hong Kong Hong Kong 陈廷汉 Department of Endocrinology and Laboratory of Reproductive biology Institute of Zoology Academia Sinica Beijing 100080 PRC Department of Zoology University of Hong Kong Hong Kong

In the present study, proteins and glycoproteins of mouse embryos at 2-cell,morula and blastocyst stages were *** techniques of ^(35)S-Met incorporation,ConA antiserum-precipitating ConA-binding proteins, mini-2D-electrophoresis, fluorography,video densitometer scanning and the computer-lmage system were used for *** of the investigations indicated that proteins and glycoproteins were synthesized by the embryos in a gradual increase manner from 2-cell to blastocyst. A relatively large amount of glycoproteins was synthesized during the morula and blastocyst *** specific small glycoproteins respectively with molecular weights about 6500 and 9000 and PIs at 5.0 and 6.5 were apparently synthesized in the blastocyst but not in the 2-cell or the morula.

关键词： implantation mouse embryos glyeoproteins mini 2D-electrophoresis computer-image analysis.

Work-up and management of a high-risk patient with primary central nervous system lymphoma

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Cancer biology & Medicine 2016年第4期13卷 514-518页

作者： Pervin A.Zeynalova Gayane S.Tumyan Mikhail b.Dolgushin Mobil I.Akhmedov Division of Hematology and bone Marrow Transplantation Department of Nuclear Medicine and Molecular Imaging N.N.Blokhin Russian Cancer Research Center

Primary central nervous system lymphoma(PCNSL) is a rare disorder that, in 95% of cases, represents diffuse large b-cell lymphoma. As such, making an accurate diagnosis is important. At present, stereotactic-guided biopsy is a recognized method of choice for tissue analysis. However, the diagnostic work-up for high-risk patients is determined by their performance status. Here,we report a case of PCNSL in a high-risk patient, for whom diagnosis was established by cerebrospinal fluid cytology and flow cytometry, which significantly shortened a diagnostic work-up period and allowed for the immediate treatment of the patient.

关键词： brain neoplasms CNS lymphoma high risk flow cytometry cerebrospinal fluid

Age of the fossil Dali Man in north-central China deduced from chronostratigraphy of the loess-palosol sequence

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Age of the fossil Dali Man in north-central China deduced fr...

无溶剂中性条件下分子I_2或Fe(No_3)_3·9H_2o/NaI原位生成的I_2催化醇与甲酸甲酰化反应(英文)

中国科学院地质与地球物理研究所2002学术年会

作者： Jule Xiao~(a,b),Changzhu Jin~c,Yizhi Zhu~b a Institute of Geology and Geophysics,Chinese Academy of Sciences,P.o.box 9825,beijing 100029,China b Institute of Earth Environment,Chinese Academy of Sciences,P.o.box 17,Xi’an 710075,China c Institute of Vertebrate Paleontology and Paleoanthropology,Chinese Academy of Sciences,beijing 100044,China

Dali Man,an archaic type of early Homo sapiens,is of great significance to the origin of Homo *** have been made during the past decades in the understanding of the fossil human skull as well as the accompanying mammalian fossils and stone ***,the absolute age of the fossil Dali Man still remains *** on the magnetic susceptibility of loess sediments and the relationship of terracing process with climatic condition,we correlated the loess sequence and the subjacent terrace alluvium at the Dali Man site with the well-studied loess-paleosol sequence at Luochuan in the central part of the Chinese Loess *** correlation indicates that the loess-paleosol sequence at the Dali Man site extends down to the paleosol S2,and the underlying fluvial deposits correspond to the loess *** the Dali Man skull appears in the basal gravel layer of the terrace,and because the deposition of the terrace gravels would occur during the transition from S3 paleosol formation to L3 loess accumulation,the age of the fossil Dali Man is inferred to be ca 270 ka,which is equivalent to the age of the boundary between the loess L3 and paleosol S3 on the magnetic susceptibility time series of the Luochuan loess-paleosol sequence.

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催化学报 2011年第1期32卷 60-64页

作者： Rostami AMIN[a] Khazaei ARDESHIR[b] Alavi-Nik HEIDAR ALI[b] Toodeh-Roosta ZAHRA[b] [a] Department of Chemistry Faculty of Science University of Kurdistan Zip Cod 66177-15175 Sanandaj Iran[b] Faculty of Chemistry bu-Ali Sina University Zip Cod 65178-38683 Hamadan Iran

Different alcohols were formylated by formic acid under solvent-free conditions in the presence of iodine as the catalyst with good-to-high yields at room temperature.I2 generated in situ from Fe(No3)3·9H2o/NaI also catalyzed the formylation of the alcohols under solvent-free *** gives a green and efficient reaction at room temperature,in which the use of toxic and corrosive molecular I2 is avoided.

关键词： alcohol formic acid formylation iodine in situ iodine solvent-free

ZroCl_2·8H_2o catalyzed one-pot synthesis of 2,4,5-triaryl-1H-imidazoles and substituted 1,4-di(4,5-diphenylimidazolyl)benzene

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Chinese Chemical Letters 2008年第7期19卷 762-766页

作者： Jaiprakash N.Sangshetti Nagnnath D.Kokare Sandeep A.Kotharkar Devanand b.Shinde Department of Chemical Technology Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad 431004 (MS)India Department of Chemical Technology Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad 431004 (MS)India Wockhardt Research CentreAurangabad 431210 (MS)India

A simple one-pot synthetic method for the preparation of 2,4,5-triaryl-lH-imidazoles from benzoin or benzil, ammonium acetate, aromatic aldehydes, and ZroCl2-8H2o catalyst is described. The ZroCl2-8H2o catalyst was found to be equally effective for aromatic and heteroaromatic aldehydes and also for the preparation of substituted 1,4-di（4,5-diphenylimidazol-yl） benzene.

关键词： ZroCl2·8H2o Triaryl-1H-imidazoles benzoin benzil Ammonium acetate Aromatic aldehydes