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61.
球形封闭容器内一个简单的煤粉燃烧爆炸模型 总被引:1,自引:0,他引:1
在分析了大量球形封闭容器内煤粉燃烧爆炸实验数据基础上,考虑了煤粉燃烧爆炸机理所涉及的湍流燃烧、相变、各种化学反应动力学过程等复杂因素,并且对球形封闭容器内由于煤粉混合不均匀造成的燃烧不充分给予了考虑,得到了球形封闭容器内煤粉燃烧爆炸特征的数值计算结果,计算的压力-时间曲线与实验结果符合较好。 相似文献
62.
Sebastian T. Le QuementMette Ishoey Mette T. PetersenPernille M. Simonsen Nanna S. HolckThomas E. Nielsen 《Tetrahedron letters》2011,52(52):7049-7053
An approach for the solid-phase synthesis of apoptosis-inducing Smac peptidomimetics is presented. Using a Rink linker strategy, tetrapeptides mimicking the N-4-terminal residue of the Smac protein [(N-Me)AVPF sequence] were synthesized on PEGA resin in excellent purities and yields. Following two synthetic routes, a known tetrapeptide, incorporating a substituted proline, previously shown to exhibit excellent biological activity in vitro as well as low toxicity, was synthesized effectively on a solid support. 相似文献
63.
Jian Hong Yang Jian Xin Pu Xue Du Hai Bo Zhang Wei Lie Xiao Han Dong Sun 《中国化学快报》2011,22(9):1078-1080
Two new compounds,corialins A(1) and B(2) were isolated from Coriaria nepalensis Wall.These new compounds were established as 7-hydroxy-3-[2,3-acetonide-(3-methylbutane)]coumarin(1) and 3-O-β-D-glucopyranosyl-3,4,5-trihydroxy-1-(3- methyl-2-butenyl)-benzene(2),on the basis of 1D and 2D NMR techniques. 相似文献
64.
Schroeder M Hogwood J Gray E Mulloy B Hackett AM Johansen KB 《Analytical and bioanalytical chemistry》2011,399(2):763-771
Protamine sulphate is an effective inhibitor of heparin and is used clinically to neutralise both low molecular weight heparins
(LMWH) and unfractionated heparin (UFH). However, protamine sulphate does not fully counter the anti-Xa effect of LMWH, even
in excess (>40 μg to 1 IU/ml). To investigate the molecular basis for this observation, the residual potencies in the presence
and absence of plasma as well as the molecular weight profiles of commercial LMWH neutralised with increasing amounts of protamine
were measured. Materials over 5000 Da are preferentially neutralised by protamine. To further investigate this molecular weight
dependence, monodisperse oligosaccharides were prepared from three commercial LMWHs. The specific anti-Xa activity for the
fractions increased with molecular weight, and was found to vary between the three preparations for oligosaccharides of the
same molecular weight. Our results indicate that protamine sulphate neutralisation is largely dependent on molecular weight,
leading to the implication that LMWHs containing a larger proportion of small oligosaccharides will not be as effectively
neutralised. Protamine sulphate neutralisation of any given LMWH is also affected by the specific anticoagulant activities
of its low molecular weight components, which varies between LMWH products, presumably with the method of manufacture. 相似文献
65.
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本文首先选取对故障比较敏感,又能反映结构动力学特性的频响函数作为诊断故障的参数。通过计算无损板在给定模态下各单元的模态能量,求得每个单元对该阶模态下全板能量的贡献,并由模态实验得到损伤前后频响函数在各阶共振峰处的变化。分析发现两者之间存在内在联系,从而得到一种分析小损伤位置和范围的新方法。 相似文献
68.
Chun Lei Sheng‐Xiong Huang Ji‐Jun Chen Jian‐Xin Pu Li‐Mei Li Wei‐Lie Xiao Jin‐Ping Liu Li‐Bin Yang Han‐Dong Sun 《Helvetica chimica acta》2007,90(7):1399-1405
Four new, highly oxygenated nortriterpenoids with the unique schisanartane skeleton, propindilactones A–D ( 1 – 4 ), were isolated from the aerial parts of Schisandra propinqua var. propinqua, together with four known schisanartane‐type compounds. The structures of the new plant constituents were established on the basis of extensive spectroscopic methods. 相似文献
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70.
The gas-liquid chromatographic behaviour of all the dimethylene interrupted methyl cis,cis-octadecadienoates was studied on polar (Carbowax 20M, FFAP, DEGA, DEGS and Silar 10C), semi-polar (XE-60) and non-polar (SE-30, OV-101 and Apiezon L) stationary phases. The equivalent chain length of each isomer is recorded; the possibility of separation and the retention pattern of these isomers are discussed. 相似文献