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111.
Maxime Noël Sergey Ananev Mattias Mases Xavier Devaux Juhan Lee Ivan Evdokimov Manuel Dossot Edward McRae Alexander V. Soldatov 《固体物理学:研究快报》2014,8(11):935-938
We report on a first study of single walled carbon nanotubes (SWCNTs) after application of dynamic (shock) compression. The experiments were conducted at 19 GPa and 36 GPa in a recovery assembly. For comparison, an experiment at a static pressure of 36 GPa was performed on the material from the same batch in a diamond anvil cell (DAC). After the high pressure treatment the samples were characterized by Raman spectroscopy and transmission electron microscopy (TEM). After exposure to 19 GPa of shock compression the CNT material exhibited substantial structural damage such as CNT wall disruption, opening of the tube along its axis (“unzipping”) and tube shortening (“cutting”). Dynamic compression to 36 GPa resulted in essentially complete CNT destruction whereas at least a fraction of the nanotubes was recovered after 36 GPa of static compression though severely damaged. The results of these shock wave experiments underline the prospect of using SWCNTs as reinforcing units in material WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
112.
利用KrF激光泵浦高压H_2,在同轴前向的受激拉曼散射(SRS)作用下,产生受激拉曼放大,1阶Stokes光对泵浦光的转换效率为17.2%,并对影响放大过程和转换效率的若干因素作了分析。 相似文献
113.
Leufroy A Noël L Beauchemin D Guérin T 《Analytical and bioanalytical chemistry》2012,402(9):2849-2859
A continuous leaching method coupled online with inductively coupled plasma mass spectrometry (ICP-MS) detection was used
to assess the maximum bioaccessibility of arsenic (As) in seafood samples. The method simulates continuous-flow digestion
by successively pumping artificial saliva, gastric and intestinal juices through a mini-column of powdered sample directly
connected to the nebuliser of an ICP-MS instrument. The method allows the real-time measurement of As being released by a
given reagent. Because the analyte is continuously removed from the system, in contrast to batch methods, the dissolution
equilibrium is driven to the right, hence quickly providing information about the worst-case scenario. Following consecutive
leaching by the digestive reagents, the leachates were subject to speciation analysis by ion-exchange chromatography with
ICP-MS detection to determine the arsenic species released. Finally, the remaining residue from the mini-column was fully
digested to verify mass balance. The method was used to determine the bioaccessibility of total As and As species in four
certified reference materials and in several real seafood samples. The mass balance was verified in each case. Generally speaking,
the non-toxic form was easily released whereas the inorganic forms were poorly bioaccessible. 相似文献
114.
A novel ferrocene-based anion receptor bearing amide and triazolium donor groups and its anion complexation have been reported. We found that it shows marked electrochemical selectivity to F(-), followed by AcO(-) > Cl(-) > Br(-) > I(-), which is in accordance with (1)H NMR titration results. 相似文献
115.
116.
In this paper, we deal with the Nagata ring R(n) in case R is obtained by a (T, I, D) construction. We characterize when R(n) is a strong S-domain and catenarian. This study allows us to provide several interesting applications and examples. 相似文献
117.
A modified InChI (International Chemical Identifier) string scheme, yaInChI (yet another InChI), is suggested as a method for including the structural information of a given molecule, making it straightforward and more easily readable. The yaInChI theme is applicable for checking the structural identity with higher sensitivity and generating three-dimensional (3-D) structures from the one-dimensional (1-D) string with less ambiguity than the general InChI method. The modifications to yaInChI provide non-rotatable single bonds, stereochemistry of organometallic compounds, allene and cumulene, and parity of atoms with a lone pair. Additionally, yaInChI better preserves the original information of the given input file (SDF) using the protonation information, hydrogen count +1, and original bond type, which are not considered or restrictively considered in InChI and SMILES. When yaInChI is used to perform a duplication check on a 3D chemical structure database, Ligand.Info, it shows more discriminating power than InChI. The structural information provided by yaInChI is in a compact format, making it a promising solution for handling large chemical structure databases. 相似文献
118.
Kyukwan Zong Seung Il Shin Dong Ju Jeon Jung No Lee Eung K. Ryu 《Journal of heterocyclic chemistry》2000,37(1):75-78
3‐Aryl‐4‐methoxycarbonylisoxazoles were prepared from the reaction of a variety of substituted benzonitrile oxides with methyl 3‐(p‐nitrobenzoyloxy)acrylate in moderate to good yields. 相似文献
119.
120.
Monojit Das Bairagya Ryan J. Bujol Prof. Noémie Elgrishi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(18):3991-4000
Development of highly active molecular electrocatalysts for fuel-forming reactions has relied heavily on understanding mechanistic aspects of the electrochemical transformations. Careful fine-tuning of the ligand environment oriented mechanistic pathways towards higher activity and optimal product distribution for several catalysts. Unfortunately, many catalysts deactivate in bulk electrolysis conditions, diminishing the impact of the plethora of highly tuned molecular electrocatalytic systems. This Minireview covers classical and emerging methods developed to circumvent catalyst deactivation and degradation, with an emphasis on successes with molecular electrocatalysts. 相似文献