排序方式: 共有59条查询结果,搜索用时 31 毫秒
31.
采用食用菌为原料,采用微波辅助热水解提取法提取出复合多糖,并用凝胶树脂对提取液中复合多糖进行纯化.对复合多糖与锌离子配合反应及产物进行初步的探讨研究.确定最佳的反应条件为反应温度为60℃、反应时间为60 min、p H值为9.0,在此条件下,锌离子∶多糖配合比为1∶1(物质的量比).采用红外光谱对产物进行了表征. 相似文献
32.
认知导航是支撑无人作战飞机自主飞行的重要导航方式,智能在线航迹规划是认知导航亟待解决的热点问题。为满足无人作战飞机的自主飞行能力需求,从"向人脑学习"的角度提出了无人作战飞机认知导航航迹规划新技术。首先分析了无人飞行器在线航路规划技术的研究现状,指出了其存在的主要问题,总结了技术发展趋势;其次针对当今在线航迹规划技术难以解决的环境/任务智能自适应问题,提出了"向人脑学习"的仿生航迹规划新方法,阐述了新方法的基本内涵与认知循环,明确了认知导航航迹规划的主要功能;最后对认知导航航迹规划的各项关键技术进行了剖析,指明了需要克服的难题。 相似文献
33.
Holub J Štíbr B Bakardjiev M Růžička A Padělková Z 《Dalton transactions (Cambridge, England : 2003)》2011,40(25):6623-6625
The heating of selected [1-(η(6)-arene)-closo-1,2,3-FeC(2)B(9)H(11)] complexes resulted in the thermal rearrangement and isolation of the corresponding 1,2,4-, 1,2,7-, and 1,2,8-cage isomers. Demonstrated here is a similar rearrangement and the NMR behaviour for isostructural [1-(η(5)-cyclopentadienyl)-closo-1,2,3-CoC(2)B(9)H(11)] compounds. 相似文献
34.
35.
36.
为深入研究柴油机微粒捕集器的微波再生机理,基于模糊综合评价法,结合层次分析主观赋权法与熵值赋权法,建立了柴油机微粒捕集器微波再生系统的两级模糊综合评价模型,完成了微波功率、微粒沉积量、排气温度、排气氧含量、排气质量流量对再生效率、再生时间、再生峰值温度及再生性能权重的定量分析,并得到了各因素取不同值时的再生性能评价结果.研究表明:排气温度对再生效率与再生时间的影响最大,权重分别为0.470 1与0.536 1;微粒沉积量对再生峰值温度的影响最大,权重为0.424 4;再生效率在再生性能中所占权重最大,为0.6162. 相似文献
37.
Shea SL Jelínek T Perera SD Stíbr B Thornton-Pett M Kennedy JD 《Dalton transactions (Cambridge, England : 2003)》2004,(10):1521-1523
Addition of PMe2Ph to fused-cluster syn-[(eta5-C5Me5)IrB18H20] 1 to give [(eta5-C5Me5)HIrB18H19(PMe2Ph)] 3 entails a diminution in the degree of intimacy of the intercluster fusion, rather than retention of inter-subcluster binding intimacy and a nido-->arachno conversion of the character of either of the subclusters. Reaction with MeNC gives [(eta5-C5Me5)HIrB18H19[C(NHMe)2]] 4 which has a similar structure, but with the ligand now being the carbene [:C(NHMe)2], resulting from a reductive assembly reaction involving two MeNC residues and the loss of a carbon atom. 相似文献
38.
Macías R Bould J Holub J Stíbr B Kennedy JD 《Dalton transactions (Cambridge, England : 2003)》2008,(35):4776-4783
Reaction of the [arachno-4-NB(8)H(12)](-) anion with [RhCl(2)(eta(5)-C(5)Me(5))](2) in CH(2)Cl(2) at room temperature affords a mixture of red '6,9' isomer [9-(eta(5)-C(5)Me(5))-nido-6,9-NRhB(8)H(11)] () and its yellow '6,8' isomer, [8-(eta(5)-C(5)Me(5))-nido-6,8-NRhB(8)H(11)] (). Under the same conditions, reactions of with [IrCl(2)(eta(5)-C(5)Me(5))](2) and [RuCl(2)(eta(6)-MeC(6)H(4)-4-(iso)Pr)](2) give the '6,8' isomers, yellow [8-(eta(5)-C(5)Me(5))-nido-6,8-NIrB(8)H(11)] () and red [8-(eta(6)-MeC(6)H(4)-4-(iso)Pr)-nido-6,8-NRuB(8)H(11)] (), respectively. In contrast, [IrCl(PPh(3))(3)] yields orange [9,9-(PPh(3))(2)-9-H-nido-6,9-NIrB(8)H(11)] (), which exhibits the '6,9' configuration. Compound isomerizes quantitatively in solution to give . At high temperatures, compound gives the yellow '6,8' species, [8,8-(PPh(3))(2)-8-H-nido-6,8-NIrB(8)H(11)] (), in low yields. Possible mechanisms for the unprecedented 6,9 --> 6,8 isomerization are discussed. 相似文献
39.
Jelínek T Císarová I Stíbr B Kennedy JD 《Dalton transactions (Cambridge, England : 2003)》2007,(42):4766-4768
[9-((ter)BuNH(2))-(anti)-9-CB(18)H(20)], in 36% yield from anti-B(18)H(22), sodium naphthalene and (ter)BuNC, constitutes the first example of a clean cluster carbon-addition Aufbau to form a macropolyhedral carbaborane. 相似文献
40.
Macías R Bould J Holub J Kennedy JD Stíbr B Thornton-Pett M 《Dalton transactions (Cambridge, England : 2003)》2007,(27):2885-2897
Reaction between [RhCl(PPh(3))(3)] and the [nido-6-NB(9)H(11)](-) anion in CH(2)Cl(2) yields orange eleven-vertex [8,8-(PPh(3))(2)-nido-8,7-RhNB(9)H(11)]. Reaction of the [nido-6-CB(9)H(12)](-) anion with [cis-PtCl(2)(PMe(2)Ph)(2)] in methanol affords yellow eleven-vertex [9-(OMe)-8,8-(PMe(2)Ph)(2)-nido-8,7-PtCB(9)H(10)], which is also formed from the reaction of MeOH with [8,8-(PPh(3))(2)-nido-8,7-PtCB(9)H(10)]. Both compounds have been characterised by single-crystal X-ray diffraction analysis and examined by NMR spectroscopy and have structures based on eleven-vertex nido-type geometries, with the metal centre and the heteroatoms in the adjacent (8)- and (7)-positions on the pentagonal open face. The metal-to-heteroborane bonding sphere of is fluxional, with a DeltaG(double dagger) value of 48.4 kJ mol(-1). DFT calculations on the model compounds [8,8-(PH(3))(2)-nido-8,7-RhNB(9)H(11)] and [8,8-(PH(3))(2)-nido-8,7-RhSB(9)H(10)] have been carried out to define the fluxional process and the intermediates involved. 相似文献