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Linear propagation of two pulses through methanol solution of aluminum phthalocyanine chloride is investigated using a modified white-light Michelson interferometer. The observed coherence time of the white light is 6 fs, and the separation between the two-excitation pulses is set to about 10 fs. The excitation is dependent on the phase-relation between the two pulses. We have observed an enhancement of the excitation when the two pulses are in-phase and strong suppression of the excitation when the two pulses are out of phase by π.  相似文献   
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Benzylic and allylic organozinc and Grignard reagents have been added to resin-bound imines to provide alpha-branched secondary amines. Many functional groups, including electrophilic groups, were compatible with this methodology. Three modules--a resin-bound primary amine, an aromatic aldehyde, and the organometallic--were independently varied to produce a combinatorial library of alpha-branched secondary amines designed as beta-3 adrenergic receptor agonists.  相似文献   
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Nano tetrapod based on conducting polythiophene (PTh) and tin-phosphate (SnP) were synthesized by in situ chemical oxidative polymerization. The morphology of the resulting polythiophene tinphosphate composite was characterized by elemental analysis, fourier transform infrared spectroscopy, thermogravimetric analysis, powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The physico-chemical characterization carried out on the composite showed that SnP was modified by conducting PTh with an enhancement of various properties. On the basis of highest distribution coefficient values for Hg(II), the composite was also used for the preparation of Hg(II) selective membrane electrode. The electrode showed working concentration range of 1 × 10?1 to 1 × 10?7 with Nernstian slope of 29.29 mV per decade change in concentration and the electrode may be used for wide working pH range of 4–8 having quick response time about 23 s. The life of electrode is 4 months without any notable drift in potential.  相似文献   
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The electrochemical nitrogen reduction reaction (NRR) offers a sustainable solution towards ammonia production but suffers poor reaction performance owing to preferential catalyst–H formation and the consequential hydrogen evolution reaction (HER). Now, the Pt/Au electrocatalyst d-band structure is electronically modified using zeolitic imidazole framework (ZIF) to achieve a Faradaic efficiency (FE) of >44 % with high ammonia yield rate of >161 μg mgcat−1 h−1 under ambient conditions. The strategy lowers electrocatalyst d-band position to weaken H adsorption and concurrently creates electron-deficient sites to kinetically drive NRR by promoting catalyst–N2 interaction. The ZIF coating on the electrocatalyst doubles as a hydrophobic layer to suppress HER, further improving FE by >44-fold compared to without ZIF (ca. 1 %). The Pt/Au-NZIF interaction is key to enable strong N2 adsorption over H atom.  相似文献   
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Theoretical constraints and limits on the masses of Higgs scalars in the standard electroweak model, in electroweak models with additional Higgs doublets and in various supersymmetric models are presented. In the standard model, the lower limit on the Higgs mass, based on vacuum stability arguments, is reviewed in detail, as are “upper limits” based on perturbative constraints. In most grand unified and all supersymmetric models, however, at least two doublets are needed. The masses of the various Higgs scalars in the two-doublet model are discussed and constraints on their masses are found, including the generalization of the above limits. The results are then generalized to models with more than two doublets. Finally, recent attempts at constructing models with low-energy supersymmetry are reviewed and it is shown that in many models, fairly stringent tree-level mass relations among the Higgs scalars can be found. These relations are interesting in that they do not refer to the supersymmetric partners of ordinary particles, and they are most restrictive in models in which the supersymmetry is explicitly broken, i.e., via arbitrary mass terms.  相似文献   
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Iqbal  Mohammad S.  Mughal  Mohammad S.  Arif  Raazia  Fatima  Sadia  Sher  Muhammad 《Chromatographia》2009,70(11):1659-1663

This papers describes the in vitro interaction of copper(II) acetylsalicylate and copper(II) salicylate with genomic DNA isolated from human blood. The two drug substances were found to bind to DNA after incubation with whole blood over night. Bonding was confirmed by detection of separated DNA electrophoresis bands for copper, copper(II) acetylsalicylate, copper(II) salicylate, acetylsalicylic acid and salicylic acid. Drug–DNA interactions were observed during electrophoresis in the form of fragmentation by formation of two bands when compared to controls. Gel permeation chromatography parameters also confirmed the occurrence of fragmentation. The use of gel permeation chromatography parameters as a measure of fragmentation of DNA is discussed. The fragmentation of genomic DNA after incubation with copper(II) acetylsalicylate and copper(II) salicylate suggested that these drug substances might be responsible for cytotoxicity in vivo.

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