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1 Results Stoichimetric quantities of lithium acetate,nickel acetate and ammonium dihydrogen phosphate were mixed with ethanol and stirred with heating until complete dissolution.A solution of 1 g chitosan in 1% acetic acid was then poured into the heated and stirred solution until all solvents have evaporated.The precursor was then sintered at 500,600,700,800,900 and 1 000 ℃ for 3 hours.X-ray diffraction results showed that single phase LiNiPO4 was obtained at sintering temperatures above 600 ℃.TEM res...  相似文献   
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Meckel-Gruber syndrome (MKS) is a genetically heterogeneous, neonatally lethal malformation and the most common form of syndromic neural tube defect (NTD). To date, several MKS-associated genes have been identified whose protein products affect ciliary function. Here we show that mutations in MKS1, MKS3 and CEP290 (also known as NPHP6) either can cause Bardet-Biedl syndrome (BBS) or may have a potential epistatic effect on mutations in known BBS-associated loci. Five of six families with both MKS1 and BBS mutations manifested seizures, a feature that is not a typical component of either syndrome. Functional studies in zebrafish showed that mks1 is necessary for gastrulation movements and that it interacts genetically with known bbs genes. Similarly, we found two families with missense or splice mutations in MKS3, in one of which the affected individual also bears a homozygous nonsense mutation in CEP290 that is likely to truncate the C terminus of the protein. These data extend the genetic stratification of ciliopathies and suggest that BBS and MKS, although distinct clinically, are allelic forms of the same molecular spectrum.  相似文献   
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The aim of the present study was to investigate the phases formed during ball milling of Al–TiO_2–NiO. For this purpose, a mixture of Al–TiO_2–NiO with a molar ratio of 6:1:1 was used. Characterization of the milled powders by X-ray diffraction, differential thermal analysis, field-emission scanning electron microscopy, and transmission electron microscopy showed the formation of nanocrystalline NiTi_2 along with AlNi. A thermodynamical investigation confirmed that NiO was reduced by Al during ball milling, which consequently promoted TiO_2 reduction and the formation of NiTi_2. Al is capable of reducing NiO either during ball milling or at temperatures above the melting point of Al; by contrast, TiO_2 can be reduced by Al only by milling.  相似文献   
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According to Vening Meinesz-Moritz (VMM) global inverse isostatic problem, either the Moho density contrast (crust-mantle density contrast) or the Moho geometry can be estimated by solv-ing a non-linea...  相似文献   
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An Al2O3-TiB2 nanocomposite was successfully synthesized by ball milling of Al, TiO2 and two B source materials of B2O3 (system (1)) and H3BO3 (system (2)). Phase identification of the milled samples was examined by Xray diffraction. The morphology and microstructure of the milled powders were monitored by scanning electron microscopy and transmission electron microscopy. It was found that the formation of this composite was completed after 15 and 30 h of milling time in systems (1) and (2), respectively. More milling energy was required for the formation of this composite in system (2) due to the lubricant properties of HaBO3 and also its decomposition to HBO2 and B2O3 during milling. On the basis of X-ray diffraction patterns and thermodynamic calculations, this composite was formed by highly exothermic mechanically induced self-sustaining reactions (MSR) in both systems. The MSR mode took place around 9 h and 25 h of milling in systems (1) and (2), respectively. At the end of milling (15 h for system (1) and 30 h for system (2)) the grain size of about 35-50 nm was obtained in both systems.  相似文献   
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Electromagnetic signals in deep reservoir are very weak so that it is difficult to predict about the presence of hydrocarbon in seabed logging(SBL) environment.In the present work,Mn0.8Zn0.2Fe2O4 nanoferrites were prepared by a sol–gel technique at different sintering temperatures of450 °C,650 °C and 850 °C to increase the strength of electromagnetic(EM) antenna.XRD,FESEM,Raman spectroscopy and HRTEM were used to analyze the phase,surface morphology and size of the nanoferrites.Magnetic properties of the nanoferrites were also measured using an impedance network analyzer.However,nanoferrites sintered at 850 °C with initial permeability of 200 and Q factor of 50 were used as magnetic feeders with the EM antenna.Lab scale experiments were performed to investigate the effect of magnetic field strength in scale tank.SPSS and MATLAB softwares were also used to confirm the oil presence in scale tank.It was observed that the magnitude of the EM waves for the antenna was increased up to 233%.Finally,the correlation values also show 208% increase in the magnetic field strength with the presence of the oil.Therefore,antenna with Mn0.8Zn0.2Fe2O4 nanoferrites based magnetic feeders can be used for deep water and deep target hydrocarbon exploration.  相似文献   
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