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1.
Microwave-induced organic reaction enhancement (‘MORE’) chemistry technique (open vessel; controlled microwave energy to stay below the boiling point of the reaction mixture) was used for the N-formylation of aliphatic and aromatic amines and amino heterocycles with aq formic acid (80%) on a multiple gram scale in a few minutes.  相似文献   
2.
This is the report of neutrino and astroparticle physics working group at WHEPP-7. Discussions and work on CP violation in long baseline neutrino experiments, ultra high energy neutrinos, supernova neutrinos and water Cerenkov detectors are discussed.  相似文献   
3.
We introduce here a new partitioning of the Hamiltonian in calculating pair-correlation energies using many-body perturbation theory, by which we are able to eliminate the off-diagonal particle–hole (ph) ladders exactly to all orders in the perturbation expansion. In this formulation, the particle states turn out to be different for each distinct pair of hole states in the correlation energy calculation. We have also included the contributions of the diagonal particle–particle (pp) and hole–hole ladders exactly to all orders. The effect of the off-diagonal pp ladders has been estimated for each pair by computing the third-, foruth- and fifth-order energies. For highly symmetric systems the present partitioning yields in general symmetry-broken orbitals. Here one may use an average kind of partitioning for all the partners of the degenerate sets, which restores the symmetry and at the same time ensures cancellation of the ph ladders exactly at the lowest order and approximately at the higher orders. Results are presented for a selection of 6π-electron conjugated systems. The correlation energy for each pair is in excellent agreement with that obtained from a partial CI calculation involving all double excitations from this pair. The advantages of implementing the present scheme in larger systems has been discussed.  相似文献   
4.
Herein, we report a facile method for synthesizing MoCo-layered double hydroxide (LDH) nanosheets employing Prussian blue analog (PBA) as the precursor. The introduction of Mo in Co-LDH modulates the electronic structure, increases the number of active sites and electrochemical surface area to improve the hydrogen evolution, oxygen evolution, and overall water splitting activity. As a result, PBA-derived Mo0.25Co0.75-LDH nanosheets demonstrated 10 mA cm?2 current density at only 220 mV and 115 mV overpotentials for OER and HER, respectively. The overall water splitting was attained at 1.52 V cell voltage for 10 mA cm?2 current density.  相似文献   
5.
We study spectral distortions of diffuse ultra-high energy (UHE) neutrino flavour fluxes resulting due to physics beyond the Standard Model (SM). Even large spectral differences between flavours at the source are massaged into a common shape at earth by SM oscillations, thus, any significant observed spectral differences are an indicator of new physics present in the oscillation probability during propagation. Lorentz symmetry violation (LV) and neutrino decay are examples, and result in significant distortion of the fluxes and of the well-known bounds on them, which may allow UHE detectors to probe LV parameters, lifetimes and the mass hierarchy over a broad range.  相似文献   
6.
The metabolic differences in the skeletal muscle of patients with Duchenne muscular dystrophy (DMD) and normal subjects (controls) were investigated using in-vitro high-resolution proton NMR spectroscopy. In all, 56 metabolites were unambiguously identified in the perchloric acid extract of muscle tissue using one- and two-dimensional NMR. The concentrations of glycolytic substrate glucose (Glc; p < 0.05), gluconeogenic amino acids such as glutamine (Gln; p < 0.05) and alanine (Ala; p < 0.05) and the glycolytic product lactate (Lac; p < 0.05) were statistically significantly lower in DMD patients as compared to controls. A significant reduction in the concentrations of total creatine (TCr; p < 0.05), glycerophosphoryl choline + phosphoryl choline + carnitine (GPC/PC/Car; p < 0.05), choline (Cho; p < 0.05) and acetate (Ace; p < 0.05) was also observed in these patients. Decrease in the level of glucose may be attributed to the reduction in the concentrations of gluconeogenic substrates or membrane abnormalities in degenerated muscle of DMD patients. Lower levels of choline containing compounds indicate membrane abnormalities. Decrease in the concentration of lactate in the muscle of DMD patients may be due to the reduction in anaerobic glycolytic activity or lower substrate concentration. The decrease in the concentration of acetate may reflect reduced transport of fatty acids into mitochondria due to decreased concentration of carnitine in DMD patients. Kreb's cycle intermediate alpha-ketoglutarate was observed only in the diseased muscle, which is suggestive of predominant oxidative metabolism for energy generation.  相似文献   
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8.

Abstract  

The conformational arrangement of an all-threo bis-THF diol compound, synthesized through the RuO4-catalysed oxidative bis-cyclization of farnesyl acetate, was determined via crystallographic analysis and detailed 2D-NMR solution studies. The bis-THF compound crystallizes in the orthorhombic Pbca space group, with unit cell parameters a = 10.496(1), b = 17.974(1), c = 19.777(2) ?, Z = 8. The final refinement converged to R 1 = 0.0484 for 4714 independent observed reflections having I > 2σ(I). There is a good agreement between the solution molecular conformation determined by 2D-NMR and the X-ray molecular conformation. The molecule adopts a folded, horse shoe-type conformation both in solution and in the crystal, that suggests aptitude to coordinate cations. Additionally, in the crystals, the molecular conformation is stabilized by intramolecular and intermolecular H-bonding.  相似文献   
9.
Azobenzene derivatives due to their photo- and electroactive properties are an important group of compounds finding applications in diverse fields. Due to the possibility of controlling the trans–cis isomerization, azo-bearing structures are ideal building blocks for development of e.g. nanomaterials, smart polymers, molecular containers, photoswitches, and sensors. Important role play also macrocyclic compounds well known for their interesting binding properties. In this article selected macrocyclic compounds bearing azo group(s) are comprehensively described. Here, the relationship between compounds’ structure and their properties (as e.g. ability to guest complexation, supramolecular structure formation, switching and motion) is reviewed.  相似文献   
10.
Measurement of heat capacities Cp at 308.65, 311.65 and 314.65 K have been made for solutions of tetraphenyl phosphonium chloride (TPPC) with methanol, ethanol, acetonitrile and water for dilute solutions (up to 0.1 M) by means of a microcalorimeter (Setaram C-80, model from France). The experimental values of heat capacity for the various solutions have been used to calculate the values of partial molar heat capacities Cp2,m of the salt in different solutions. The results are studied in relation to the special features of solvations in solutions of the TPPC.  相似文献   
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