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A new form of cobalt succinate has been discovered using high-throughput methods and its structure was solved by single crystal X-ray diffraction. Co7(C4H4O4)4(OH)6(H2O)37H2O crystallizes in the monoclinic space group P21/c with cell parameters: a=7.888(2) Å, b=19.082(6) Å, c=23.630(7) Å, β=91.700(5)°, V=3555(2) Å3, R1=0.0469. This complex structure, containing 55 crystallographically distinct non-hydrogen atoms, is compared to the previously reported nickel phase, characterized using ab initio structure solution from synchrotron powder diffraction data.  相似文献   
94.
Investigation of the formation of complex reaction products in the gas-phase system O3/NO2/(Z)-2-butene by combination of linear reactors with IR. matrix and microwave Stark Spectroscopy is reported. Besides the polyatomic products observed earlier in the gas-phase ozonolysis of (Z)-2-butene, the following products were identified; N2O5, HNO3, HNO4, CH3NO2, CH3ONO, CH3COONO2 and CH3COO2NO2 (peroxyacetyl nitrate, PAN). Matrix IR. spectra of N2O5, HNO3. CH3COONO, CH3COONO2 required for reference purposes are presented. It is shown that PAN-formation occurs already in the absence of light. A reaction scheme is proposed for explanation of the observed complex NOx-containing products, which assumes methyldioxirane as a central intermediate. Particular reaction steps of the scheme will be discussed, including thermochemical estimates of reaction enthalpies.  相似文献   
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Ohne ZusammenfassungDiese Arbeit wurde von der Philosophischen Fakultät der Universität München, II. Sektion, als Dissertation angenommen.  相似文献   
98.
Ion kinetics in low-pressure (e.g., 1 mtorr), electropositive, RF glow discharge sheaths are studied using a Monte-Carlo-based computer simulation. The numerical model integrates particle trajectories using a spatially nonlinear, time-varying model of the electric field in the RF sheath. A scaling relationship is then discussed, relating the normalized ion energy spread to the ratio of ion sheath transit time to the RF period. The scaled numerical data shows good agreement with existing numerical and experimental data  相似文献   
99.
The paper describes an investigation of the characteristics of spherical focusing Bragg-reflection mirrors. The integral reflectivity of bent crystals at Bragg angles 80–90°, the width of the spectrum of the reflected x-rays, and the spatial resolution of the images formed by the focusing crystals are considered. Results are presented of the calculated integral reflectivity of bent silicon and quartz crystals of different orientation and in different orders of reflection. The feasibility is demonstrated of laser-plasma diagnostics using the images obtained with the aid of a multichannel x-ray microscope based on focusing crystals. Possible schemes of active diagnostics of a dense laser plasma using a monochromatic transilluminating x-ray beam are considered.Laser Plasma Laboratory, Lebedev Physics Institute. Translated from FIAN Preprint No. 143, Lebedev Physics Institute of the Academy of Sciences of the USSR, Moscow, 1989.  相似文献   
100.

Background  

Amyotrophic lateral sclerosis (ALS) is an age-dependent neurodegenerative disease that causes motor neuron degeneration, paralysis and death. Mutations in Cu, Zn superoxide dismutase (SOD1) are one cause for the familial form of this disease. Transgenic mice expressing mutant SOD1 develop age-dependent motor neuron degeneration, skeletal muscle weakness, paralysis and death similar to humans. The mechanism whereby mutant SOD1 induces motor neuron degeneration is not understood but widespread mitochondrial vacuolation has been observed during early phases of motor neuron degeneration. How this vacuolation develops is not clear, but could involve autophagic vacuolation, mitochondrial permeability transition (MPT) or uncharacterized mechanisms. To determine which of these possibilities are true, we examined the vacuolar patterns in detail in transgenic mice expressing mutant SOD1G93A.  相似文献   
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