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151.
152.
Antoine Franche Claire Imbs Antoine Fayeulle Franck Merlier Muriel Billamboz Estelle Léonard 《中国化学快报》2020,31(3):706-710
Botrytis cinerea is a necrotrophic fungusth at a ffects various plant species.Chemical control is an ecessity and as much as possible,eco-friendly conditions and bioresources to obtain these chemicals should be used.In this context,a series of products w as obtained from salicylaldehyde using zinc as a powerful reagent and tested for antifungal activity against Botrytis cinerea. 相似文献
153.
Estelle Martineau Jean-Nicolas Dumez Patrick Giraudeau 《Magnetic resonance in chemistry : MRC》2020,58(5):390-403
Nuclear magnetic resonance (NMR) is a well-known analytical technique for the analysis of complex mixtures. Its quantitative capability makes it ideally suited to metabolomics or lipidomics studies involving large sample collections of complex biological samples. To overcome the ubiquitous limitation of spectral overcrowding when recording 1D NMR spectra on such samples, the acquisition of 2D NMR spectra allows a better separation between overlapped resonances while yielding accurate quantitative data when appropriate analytical protocols are implemented. Moreover, the experiment duration can be considerably reduced by applying fast acquisition methods. Here, we describe the general workflow to acquire fast quantitative 2D NMR spectra in the “omics” context. It is illustrated on three representative and complementary experiments: UF COSY, ZF-TOCSY with nonuniform sampling, and HSQC with nonuniform sampling. After giving some details and recommendations on how to apply this protocol, its implementation in the case of targeted and untargeted metabolomics/lipidomics studies is described. 相似文献
154.
Marie Fabritius Haithem Chtioui Giovanni Battistella Jean-Marie Annoni Kim Dao Bernard Favrat Eleonora Fornari Estelle Lauer Philippe Maeder Christian Giroud 《Analytical and bioanalytical chemistry》2013,405(30):9791-9803
A cross-over controlled administration study of smoked cannabis was carried out on occasional and heavy smokers. The participants smoked a joint (11 % Δ9-tetrahydrocannabinol (THC)) or a matching placebo on two different occasions. Whole blood (WB) and oral fluid (OF) samples were collected before and up to 3.5 h after smoking the joints. Pharmacokinetic analyses were obtained from these data. Questionnaires assessing the subjective effects were administered to the subjects during each session before and after the smoking time period. THC, 11-hydroxy-THC (11-OH-THC) and 11-nor-9-carboxy-THC (THCCOOH) were analyzed in the blood by gas chromatography or liquid chromatography (LC)-tandem mass spectrometry (MS/MS). The determination of THC, THCCOOH, cannabinol (CBN), and Δ9-tetrahydrocannabinolic acid A (THC-A) was carried out on OF only using LC-MS/MS. In line with the widely accepted assumption that cannabis smoking results in a strong contamination of the oral cavity, we found that THC, and also THC-A, shows a sharp, high concentration peak just after smoking, with a rapid decrease in these levels within 3 h. No obvious differences were found between both groups concerning THC median maximum concentrations measured either in blood or in OF; these levels were equal to 1,338 and 1,041 μg/L in OF and to 82 and 94 μg/L in WB for occasional and heavy smokers, respectively. The initial WB THCCOOH concentration was much higher in regular smokers than in occasional users. Compared with the occasional smokers, the sensation of confusion felt by the regular smokers was much less while the feeling of intoxication remained almost unchanged. Figure
Time profiles of THC, 11-OH-THC, and THCCOOH in whole blood for occasional (a) and heavy cannabis smokers (b) 相似文献
155.
156.
David M. Haddleton Estelle Depaquis Elizabeth J. Kelly Dax Kukulj Stuart R. Morsley Stefan A. F. Bon Michael D. Eason Andrew G. Steward 《Journal of polymer science. Part A, Polymer chemistry》2001,39(14):2378-2384
This article describes the use of cobalt‐mediated catalytic chain transfer in aqueous solution under fed conditions for the preparation of macromonomers of acidic, hydroxy, and zwitterionic functional monomers. Use of a batch reaction leads to hydrolysis of catalyst, a mixture of mechanisms and poor control of the reaction. A feed process is described that adds catalyst as a solution in monomer over the course of the reaction. The feed process is applied to a range of monomers of methacrylic acid ( 2 ), 2‐aminoethyl methacrylate hydrochloride ( 3 ), 2‐hydroxyethyl methacrylate ( 4 ), 2‐methacryloxyethyl phosphoryl choline ( 5 ), glycerol monomethyl methacrylate ( 6 ), and 3‐O‐methacryloyl‐1,2:5,6‐di‐O‐isopropylidene‐D ‐glucofuranose ( 7 ). Use of the feed process for water‐soluble monomers in conjunction with 1 as a catalytic chain‐transfer agent gives high‐conversion, > 90%, water‐soluble macromonomers. The number‐average molecular mass (Mn was determined by integration of the 1H NMR spectrum comparing the vinylic end group with the remainder of the backbone. Pseudo‐Mayo plots were constructed by measuring the Mn at high conversion as a function of [monomer]/[catalyst] to give observed chain‐transfer constants of 1120, 958, and 1058 for 4, 6, and 2, respectively. All products were obtained as relatively high‐solid, homogeneous, low‐viscosity aqueous solutions. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2378–2384, 2001 相似文献
157.
In an ongoing work directed towards the synthesis of nucleoside derivatives containing an l-alanine residue, we report herein a novel observation concerning the Ns-protecting group: the epimerization of the α-hydrogen in acylation conditions. 相似文献
158.
Using fermionic techniques, we compute exactly the large deviation function (ldf) of the time-integrated injected power in
several one-dimensional dissipative systems of classical spins. The dynamics are T=0 Glauber dynamics supplemented by an injection mechanism, which is taken as a poissonian flipping of one particular spin.
We discuss the physical content of the results, specifically the influence of the rate of the Poisson process on the properties
of the ldf. 相似文献
159.
K. Veselinov F. Grillot P. Miska E. Homeyer P. Caroff C. Platz J. Even X. Marie O. Dehaese S. Loualiche A. Ramdane 《Optical and Quantum Electronics》2006,38(4-6):369-379
Quantum dot (QD) lasers exhibit many interesting and useful properties such as low threshold current, temperature insensitivity
or chirpless behavior. In order to reach the standards of long-haul optical transmissions, 1.55 μm InAs QD lasers on InP substrate
have been developed. Based on time resolved photoluminescence (PL) measurements, carrier dynamics behavior is at first investigated.
Electroluminescence (EL) results are then shown at room temperature exhibiting a laser emission centered at 1.61 μm associated
to a threshold current density as low as 820 A/cm2 for a six InAs QD stacked layers. Finally, a rate equation model based on the reservoir theory is used to model both time-resolved
photoluminescence (TRPL) and electroluminescence results. It is shown that carrier dynamic calculations are in a good agreement
with measurements since the saturation effect occurring at high injected power is clearly predicted.
P. Miska: Previously at Laboratoire d’Etude des Nanostructures à Semiconducteurs. 相似文献
160.
W. von Oertzen H. Fuchs A. Gamp H. Homeyer U. Jahnke J. C. Jacmart 《Zeitschrift für Physik A Hadrons and Nuclei》1980,298(3):207-211
Evaporation residue cross sections for the fusion of52Cr and110Pd were studied at four energies close to the barrier (up toE CM ?E B =26 MeV). The cross sections were analysed using a multiple-chance fission/evaporation calculation. Agreement with the data is obtained with a fission barrier reduced by 40 to 20%, depending on incident energy. 相似文献