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71.
Akiba Y Beavis D Beery P Britt HC Budick B Chasman C Chen Z Chi CY Chu YY Cianciolo V Cole BA Costales JB Crawford HJ Cumming JB Debbe R Engelage J Fung SY Gonin M Gushue S Hamagaki H Hansen O Hayano RS Hayashi S Homma S Kaneko H Kang J Kaufman S Kehoe WL Kurita K Ledoux RJ Levine MJ Miake Y Morrison DP Morse RJ Moskowitz B Nagamiya S Namboodiri MN Nayak TK Olness J Parsons CG Remsberg LP Roehrich D Rothschild P Sakurai H Sangster TC Seto R Soltz R Stankus P Steadman SG Stephans GS Sung T 《Physical review letters》1996,76(12):2021-2024
72.
The base alkylation of 2,3-dimercapto-1-propanol with alkyl halides leads in good yield to 2,3-bis(alkylthio)-1-propanol and dialkyl sulfide. The reaction of 2,3-bis(alkylthio)-1-propanol with catalytic concentrated sulfuric acid proceeds with rearrangement to give 1,2,3-tris(alkylthio)propane and dialkyl disulfide. The rearrangement reaction takes place through a common intermediate thiaranium intermediate 8. 相似文献
73.
A detailed singlet potential energy surface(PES) of [Si,C,O,O] system including a van der Waals (vdW) comples SiO……CO2,eight isomers,and twelve transiton states is investigated by MP2 and QCISD(T) (single-point)methods.At the final QCISD(T)/6-311 G(2df)//MP2/6-311G(d) level with zero-point energy included,the complex SiO……CO is found to be thermodynamically and kinetically the most stable species.Although eight ismoers are located as local energy minima,they are rather unstable toward isomerization to the dissociation fragments or comples.For the reaction of silocon atoms with carbon dioxide,two competitive reaction channels are found,and the primary pathway,which leads to the products of SiO and CO fragments,is the direct oxygen-abstraction process from carbon dioxide by silicon atom with a41.16 kJ/mol reaction barrier height.Our predications are in good agreement with previous experimental and theoretical studies. 相似文献
74.
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76.
Zh. Bo J. H. Yan X. D. Li Y. Chi K. F. Cen B. G. Chéron 《Plasma Chemistry and Plasma Processing》2007,27(5):546-558
The combined effects of oxygen and water vapor on three typical volatile organic compounds, i.e. tetrachloromethane, n-butane and toluene, decomposition efficiency under gliding arc gas discharge conditions are studied. The electron density
and the density of the reactive radicals such as O and OH are modified by addition of oxygen and water vapor. Consequently,
the decomposition process can be enhanced or suppressed, depending on the involved chemical structures and reaction channels.
The addition of oxygen and water vapor suppresses the tetrachloromethane decomposition which indicates that this process is
mainly controlled by the electron dissociation reactions. By contrast, the n-butane and toluene decompositions are enhanced, which shows that they can be mainly ascribed to the radical induced reactions.
Especially, in a moist atmosphere the OH radicals are supposed to play the most important role in the n-butane decomposition process. 相似文献
77.
Misra AK Sharma SK Chio CH Lucey PG Lienert B 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(10):2281-2287
A remote Raman system has been developed utilizing a 532nm pulsed laser and gated intensified charged couple device (ICCD) detector in the oblique geometry. When the system is set for 50m sample distance it is capable of measuring Raman spectra of minerals located at distances in the range of 10-65m from the telescope. Both daytime and nighttime operations are feasible and the spectra of minerals can be measured in a short period of time, of the order of a few seconds. In oblique geometry, measured sampling depth is more than 30m, during which the system maintains very high performance without any adjustments. Much longer sampling depth (0.1-120m) has been observed when the system is configured in the coaxial geometry. Clear advantages of using a gated detection mode over the continuous (CW) mode of operation in reducing the background signal and eliminating long-lived fluorescence signals from the Raman spectra are presented. The performance of the pulsed Raman system is demonstrated by measuring spectra of Raman standards including benzene (C(6)H(6)) and naphthalene (C(10)H(8)), a low Raman cross section silicate mineral muscovite (KAl(2)(Si(3)Al)O(10)(OH)(2)), and a medium Raman cross section mineral calcite (CaCO(3)). 相似文献
78.
The design, synthesis and evaluation of a pentacyclic scaffold, CWO-324 to mimic saframycin A is described. CWO-324 is readily synthesized in five steps from 1,4-diacetyl-piperazine-2,5-dione and 2,5-dimethoxybenzaldehyde. CWO-324 was found to scission DNA, binds to bases 69-83(5′-GCAGTCAGG CACCGT-3′) of Hind III/Rsa I from plasmid pBR322 DNA in a foot-printing study and possesses anti-tumor activity. 相似文献
79.
A novel silane coupling agent bearing sulfobetaine group, N,N-diethyl-N-(3-sulfopropyl)-aminopropyl- trimethoxysilane (DESATS), was first designed, synthesized and characterized. Its solution property was studied by means of dynamic light scattering. DESATS was successfully bonded onto the surface of the glass and proved by ESCA. Platelet adhesion assay in vitro indicated that the nonthrombogenicity of glass slide modified with DESATS is greatly improved. 相似文献
80.
Chi YS Jung YH Choi IS Kim YG 《Langmuir : the ACS journal of surfaces and colloids》2005,21(10):4669-4673
In this paper, we report surface-initiated d(A-T) polymerization by Taq DNA polymerase as a method for constructing DNA-tethered surfaces using an enzyme. The enzymatic polymerization was conducted successfully via two steps: tethering of oligo d(A-T)s onto the surface presenting carboxylic acids by amide coupling and surface-initiated polymerization using Taq DNA polymerase. In this enzymatic polymerization process, the design and construction of carboxylic acid-presenting surfaces were found to be an important factor: DNA growth did not occur on the gold surface coated only with the self-assembled monolayer (SAM) of 16-mercaptohexadecanoic acid (MHDA), but effectively proceeded on the surfaces presenting mixed SAMs of MHDA and 1-pentadecanethiol. The coupling of oligo d(A-T)s and the subsequent DNA polymerization reaction were characterized by polarized infrared external reflectance spectroscopy, ellipsometry, X-ray photoelectron spectroscopy, and atomic force microscopy. 相似文献