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1.
As “rapporteur” for the papers submitted to this conference in the general area of muonium chemistry, I briefly review the major developments since μSR86, and attempt to show how the papers presented at μSR90 relate to each other and work published in the intervening years. Some topics are discussed in more detail than others, reflecting my own interests and views on what is of current importance. Nevertheless, I try to cover all current research in muonium chemistry. The major areas are: early events following muon thermalization, including subsequent loss of muon polarization (the “missing fraction”); molecular structure and dynamics, primarily of muonium-substituted free radicals: and reaction kinetics.  相似文献   

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Gérard Demazeau 《高压研究》2013,33(1-6):203-212
Abstract

Pressure was developed during the 20th century. The most important illustration of the use of high pressure in Materials Science was the synthesis of diamond at the beginning of the fifties.

This contribution will describe the main scientific research axis developed these last years and based on high pressure (synthesis of new materials, stabilization of specific structures, crystal-growth, preparation of finely divided materials…).

In parallel some industrial developments will be analyzed.

In conclusion, the potential of high pressure will be sketched for the near future.  相似文献   

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James  Ian W. 《Molecular diversity》1997,3(3):181-190
The solid phase chemistry literature for much of 1997 has been reviewed with an emphasis on organic chemistry. Reactions have been classified according to both the types of chemistry performed and the products formed on the solid phase. Examples of inorganic chemistry performed on the solid phase have also been included. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

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Summary Recent literature in solid-phase organic and inorganic chemistry has been reviewed. Papers have been collated according to the compounds prepared on the solid phase and the types of transformations performed. Covered are more than 40 chemical transformations as well as the preparation of more than 50 functional groups.  相似文献   

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Dual standards acceptance and industry consolidation through an increased number of mergers, acquisitions, and joint ventures are among the recent changes that have had an impact on the local area network (LAN) industry. The article highlights the industry changes that will affect both end-users and vendors of LANs.  相似文献   

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In this review, applications of silicon carbide-based microtiter platforms designed for use in combination with dedicated multimode microwave reactors are described. These platforms are employed not only for the efficient parallel synthesis of compound libraries, but also in the context of high-throughput reaction screening/optimization and a number of other (bio)analytical and biomedical applications. Since the semiconducting plate material (silicon carbide) is strongly microwave absorbing and possesses high thermal conductivity, no temperature gradients across the microtiter plate exist. Therefore, many of the disadvantages experienced in attempting to perform microtiter plate chemistry under conventional microwave conditions can be eliminated. In general, the silicon carbide-based microtiter platforms allow sealed vessel processing (either directly in the well or in glass vials placed into the wells) of volumes ranging from 0.02–3.0 mL at a maximum temperature/pressure limit of 200°C/20 bar. Depending on the specific plate and rotor configuration, a maximum of 80–192 transformations can be carried out in parallel in a single microwave irradiation experiment under strict temperature control. A platform type utilizing HPLC/GC vials as reaction vessels allows analysis directly from the reaction vessel eliminating the need for a transfer step from the reaction to the analysis vial. The latter system is particularly useful for analytical applications as well as reaction optimization/screening.  相似文献   

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Optical data processing is an advancing field which has received much attention in recent years. Optical techniques have already shown their applicability in target identification, advanced signal processing operations and advanced linear algebra operations. The potential capabilities of processing of data using photons instead of electrons as the carrier of information have established, beyond any doubt, that the optical techniques will be the next generation technology surpassing electronic techniques in some important areas such as air traffic control, missile guidance and remote sensing. Although great strides have been made in all the areas of optical data processing, the goal of high performance, high speed and very accurate all-optical computers would be realised only around the year 1995. The main difficulty is that the required materials for high resolution and fast spatial light modulators and optical interconnects are yet to be perfected. The present paper reviews the recent trends and the future prospects of optical data processing.  相似文献   

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In recent years, a large variety of microwave magnetic materials has been developed, with different compositions, shapes, and fabrication processes. The physics of the dynamic magnetic responses of these materials is very rich, due to the interplay between the intrinsic magnetic properties of the materials, the domain structure, and dynamic shape effects. These materials are associated to a variety of applications, some of them well-established, for direct interaction with rf waves; others corresponding to etablished uses of magnetic materials, but at higher speeds or higher frequencies; and some in association with hot topics in the magnetic or rf communities including metamaterials, nanoscale structures, and nonlinear devices.  相似文献   

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Molecular Diversity - MgCl2 has been reported to be a versatile reagent especially as a Lewis acid catalyst in a variety of organic transformations including the preparation of heterocyclic...  相似文献   

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H. Machner 《Pramana》2006,66(5):867-876
The COSY accelerator in Jülich is presented together with its internal and external detectors. The physics program performed recently is discussed with emphasis on strangeness physics and precision experiments  相似文献   

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The Biginelli reaction, which involves the interaction of ethyl acetoacetate, urea, and an appropriate aryl aldehyde, was first discovered by Pietro Biginelli about 120 years ago. The Biginelli products (3,4-dihydropyrimidin-2(1 $H$ )-ones) are interesting materials due to their significant pharmacological and structural profiles. In the last decades, the asymmetric synthesis as a powerful tool has an effective impact on the Biginelli products and has increased their potencies and applications as drugs. Having the importance of this subject in mind, in this review we wish to present the recent rapid progress of asymmetric Biginelli reaction.  相似文献   

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This review details a now established area within the isonitrile multi-component reaction (IMCR) field of study, namely employing bi-functional reagents in the Ugi reaction for the construction of screening sets with the additional element or even possibly ‘metric’ of enhanced ‘iterative efficiency potential’ The concept of ‘iterative efficiency’ will be briefly introduced, coupled with discussion on new synthetic routes to select bi-functional IMCR precursors and their use in the generation of pharmacologically relevant ‘molecular diversity’  相似文献   

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Abstract

It is widely recognized that relevant new chemistry is being discovered by applying high pressures. The study of the equation of state, pressure-induced phase transitions, reactivity, etc., of molecular systems are topics of increasing interest in high pressure science. This paper compiles recent studies performed by the author on molecular systems at high pressures. This includes, on the theoretical side, a reference to a universal model of EOS for both liquids and solids at high pressure. Several experiments performed by the author are also discussed; among others, a high pressure polymerization of carbon monoxide, the design of an anvil cell system developed in our laboratory, introducing an alternative Raman pressure scale when sapphires are mounted as anvils (SAC configuration) and, finally, several actual SAC experiments are presented, including examples of phase transitions and reactivity at high pressure on double and triple bonded molecular systems.  相似文献   

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