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Simone Pilon Steen Ingemann Jørgensen Prof. Dr. Jan H. van Maarseveen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(7):2310-2314
After earlier unsuccessful attempts, this work reports the application of covalent templating for the synthesis of mechanically interlocked molecules (MiMs) bearing no supramolecular recognition sites. Two linear strands were covalently connected in a perpendicular fashion by a central ketal linkage. After subsequent attachment of the first strand to a template via temporary benzylic linkages, the second was linked to the template in a backfolding macrocyclization. The resulting pseudo[1]rotaxane structure was successfully converted to a [2]catenane via a second macrocyclization and cleavage of the ketal and temporary linkages. 相似文献
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Emilien Burger David Bourgarit Vincent Frotté Fabien Pilon 《Journal of Thermal Analysis and Calorimetry》2011,103(1):249-256
This article deals with one specific step of the copper extractive metallurgy process: the roasting of iron–copper sulphides.
It aims at shedding light on an archaeological issue: the reconstruction of the copper extractive metallurgy processes during
protohistory (IVe–IIe millennium BC). Experimental simulations are performed at laboratory scale by modelizing the conditions of protohistoric
furnaces. Kinetic of roasting is studied by thermogravimetry combined with the physico-chemical analysis of synthetic products.
The influence of two parameters is studied: (i) the temperature (773, 973 and 1173 K) and (ii) the granularity of the roasted
ores (1 mm and 100 μm). In each case, the chemical mechanism governing the oxidation of iron copper sulphide is proposed.
Apart from one extreme case (∅ = 1 mm; T = 773 K), it is showed that kinetic is controlled by the transport of molecular oxygen (O2) from the gas to the grain surface. Moreover, we prove that, in some cases where the diffusivity of gaseous oxygen is low,
roasting can be accelerated by the presence of an oxide, which constitute an in-situ source of oxygen. Theses experiments
support the hypothesis that such a technique could have allowed a roasting process where iron and sulfur were removed by the
solid oxygen instead of the gaseous oxygen. These results allow to validate a one-step copper smelting process starting from
sulphidic ores, and to identify the experimental parameters of this process. 相似文献
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S.A. Wallington C. Pilon J.D. Wright 《Journal of Sol-Gel Science and Technology》1997,8(1-3):1127-1132
Porous sol-gel glasses containing entrapped fluorescent-labelled -cyclodextrin have been prepared from tetramethylorthosilicate (TMOS). Small non-polar solvent molecules such as cyclohexane and toluene displace the fluorescent label from the cyclodextrin cavity, and the resulting decrease in fluorescence intensity is proportional to the solvent vapour concentration in the range 40–100 ppm, and is reversible. Polar solvents such as acetone give no response. Strategies for optimisation of the system are discussed. 相似文献
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Pierre?Pilon Daniel?Dion Marie-Josée?BinetteEmail authorView authors OrcID profile 《International Journal for Ion Mobility Spectrometry》2016,19(2-3):113-119
Ion mobility spectrometry (IMS) is a well known field technique for the detection of various materials such as explosives and narcotics. IMS has been used for the detection and identification of nicotine, and this paper describes a simple preparation method and analysis using an Ionscan 500DT which could be used in a field environment for the detection of nicotine in e-liquids. E-liquids containing nicotine are presently a topic of much debate in many countries and their shipment across the Canadian border is prohibited. The method described here would allow border officers or any other operators of IMS instruments to use this technique to correctly determine the presence or absence of nicotine in the e-liquid; this would allow the timely importation of the e-liquids with no nicotine and restrict the laboratory analysis only to those liquids containing nicotine. The IMS method has been used on a number of samples received from manufacturers of e-liquids as well as samples seized at the border. The results of the IMS analysis correspond well with those obtained using a Gas Chromatograph – Mass Spectrometer (GC-MS) method of analysis for nicotine. 相似文献
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T. Binoth J.Ph. Guillet E. Pilon M. Werlen 《The European Physical Journal C - Particles and Fields》2000,16(2):311-330
We discuss the production of photon pairs in hadronic collisions, from fixed target to LHC energies. The study which follows
is based on a QCD calculation at full next-to-leading order accuracy, including single and double fragmentation contributions,
and implemented in the form of a general purpose computer program of “partonic event generator” type. To illustrate the possibilities
of this code, we present a comparison with observables measured by the WA70 and D0 collaborations, and some predictions for
the irreducible background to the search of Higgs bosons at LHC in the channel . We also discuss theoretical scale uncertainties for these predictions, and examine several infrared sensitive situations
which deserve further study.
Received: 24 November 1999 / Revised version: 13 March 2000 / Published online: 8 June 2000 相似文献
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John D. Childs Michael J. Ellison† Raymond Pilon 《Photochemistry and photobiology》1983,37(5):513-519
Cyclobutyl pyrimidine dimers composed of 5-hydroxymethylcytosine and thymine (5HMC>T dimer for a mutant of T4 ( denV ) that is unable to excise pyrimidine dimers from its DNA. The ability of 5HMC to form dimers suggests that other modified pyrimidines such as 5-methylcytosine can participate in dimer formation, particularly at the UV wavelengths in sunlight likely to be responsible for the induction of skin cancer. 相似文献
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Alan Cesar Pilon Marcelo Del Grande Maíra R. S. Silvrio Ricardo R. Silva Lorena C. Albernaz Paulo Czar Vieira Joo Luis Callegari Lopes Laila S. Espindola Norberto Peporine Lopes 《Molecules (Basel, Switzerland)》2022,27(5)
Dengue is a neglected disease, present mainly in tropical countries, with more than 5.2 million cases reported in 2019. Vector control remains the most effective protective measure against dengue and other arboviruses. Synthetic insecticides based on organophosphates, pyrethroids, carbamates, neonicotinoids and oxadiazines are unattractive due to their high degree of toxicity to humans, animals and the environment. Conversely, natural-product-based larvicides/insecticides, such as essential oils, present high efficiency, low environmental toxicity and can be easily scaled up for industrial processes. However, essential oils are highly complex and require modern analytical and computational approaches to streamline the identification of bioactive substances. This study combined the GC-MS spectral similarity network approach with larvicidal assays as a new strategy for the discovery of potential bioactive substances in complex biological samples, enabling the systematic and simultaneous annotation of substances in 20 essential oils through LC50 larvicidal assays. This strategy allowed rapid intuitive discovery of distribution patterns between families and metabolic classes in clusters, and the prediction of larvicidal properties of acyclic monoterpene derivatives, including citral, neral, citronellal and citronellol, and their acetate forms (LC50 < 50 µg/mL). 相似文献
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T. Binoth J.Ph. Guillet E. Pilon M. Werlen 《The European Physical Journal C - Particles and Fields》2002,24(2):245-260
We discuss the production of pion pairs with a large invariant mass in hadronic collisions. We present a study based on a
perturbative QCD calculation at full next-to-leading order accuracy, implemented in the computer programme DIPHOX. We provide a comparison of various predictions with the corresponding observables measured by the E706 fixed target experiment.
Discrepancies between data and next-to-leading order calculation are carefully analysed. We classify the theoretical next-to-leading
order distributions with respect to their infrared sensitivity, and explain which distributions need improvements. Further,
we comment on the energy scale dependences of non pertubative effects.
Received: 8 November 2001 / Published online: 5 April 2002 相似文献