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101.
Tarik E. Ali 《Phosphorus, sulfur, and silicon and the related elements》2016,191(9):1223-1228
Mass fragmentation pathways of eight synthetic organophosphorus compounds, belonging to azolyl, azinyl, and azepinyl phosphonates as cyclic α-aminophosphonates 1a,b–4a,b were investigated by electron impact mass spectrometry with the aim of obtaining a better understanding of their fragmentation processes. The intensity of the recorded molecular ion peaks showed moderate values. Compounds 1a,b–3a,b have almost identical fragmentation routes via easy elimination of phosphonate groups which can be fragmented into the cation PO2 as base peaks. On the contrary, compounds 4a,b started their fragmentation via removal of 4-chlorophenyl moieties. 相似文献
102.
103.
S. M. Peregudova L. I. Denisovich A. I. Yarmolenko L. N. Novikova N. A. Ustynyuk 《Russian Journal of Electrochemistry》2006,42(3):272-275
Using cyclic voltammetry method, the reduction of cationic η6-fluorene complexes of manganese [(η6-9-R-C13H9)Mn(CO)2L]PF6 (L = CO, R = H (1 +); L = CO, R = CH3 (2 +); L = PnBu3, R = H (3 +); L = CO, R = tBu (4 +)) is studied. It is shown that, depending on the nature of a substituent in the position 9 of the fluorene ligand, the reduction occurs either with the detachment of an H atom from position 9 to give zwitterion compounds (complexes 1 ±, 2 ±, 3 ±) or with the attachment of an H atom into the coordinated ring of the fluorene ligand to given η5-cyclohexadienyl complex (η5-9-tBu-C13H9)Mn(CO)3 (5). 相似文献
104.
V. V. Kuznetsov 《Chemistry of Heterocyclic Compounds》2006,42(5):559-569
New examples of the borylation of a series of five-and six-membered saturated 1,3-and 1,3,2-heterocycles with the formation
of cyclic boric esters are described. The probable mechanism of the reaction is discussed.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 643–654, May, 2006. 相似文献
105.
A wide size range of SiO2 particles were synthesized and were used as enzyme immobilization carriers to fabricate glucose biosensors. The size of the particles was in the range of 17-520 nm. These biosensors could be operated under physiological conditions (0.1 M phosphate buffer, pH 7.2). Particle size could affect the performance of SiO2 modified glucose biosensors drastically. The smaller particles had higher performance. The smallest SiO2 modified biosensor could work well in the glucose concentration range of 0.02-10 mM with a correlation coefficient of 0.9993. Its sensitivity was 2.08 μA/mM and the detection limit was 1.5 μM glucose. 相似文献
106.
Marta Ambrová Jana Jurišová Alexandra Sýkorová Dalibor Uher Vladimír Danielik Ján Híveš 《Chemical Papers》2008,62(2):154-159
The electrochemical behaviour of the LiF-La2O3 and LiF-CaF2-La2O3 systems was investigated by means of cyclic voltammetry. Several types of working electrodes (spectrographic pure graphite,
W, Mo, Ni, Cu) were used. It was found that chemical reactions take place in the system during the dissolution of lanthanum
oxide. The reduction of lithium cations occurred at the most positive potential from the species formed in the melt on ‘inert’
cathodes (W, Mo). The reactive cathodes (Cu, Ni) allowed the lanthanum deposition with depolarisation. 相似文献
107.
Andrew O Simm Xiaobo Ji Craig E Banks Michael E Hyde Richard G Compton 《Chemphyschem》2006,7(3):704-709
In situ atomic force microscopy (AFM) is used to study the growth of cobalt nuclei on a boron doped diamond electrode under potentiostatic control. The rate of growth of the nuclei at the electrode surface is monitored using AFM as a function of time at different deposition potentials. The nucleation of cobalt nuclei is found to be "instantaneous" and the growth of the nuclei is shown to be kinetically rather than diffusionally controlled over periods of tens and hundreds of seconds. At very short times (<10 seconds) the kinetics of nucleation are apparent. 相似文献
108.
采用
109.
交通荷载作用下低路堤动力特性试验研究 总被引:9,自引:0,他引:9
结合连盐高速低路堤,对路堤进行了动应力、振动响应等现场测试,分析了路基中附加动应力及振动位移的变化规律.并且通过应力控制的室内动三轴试验,采用一定的动应力频率、不同的循环应力比来模拟交通荷载,研究了在循环荷载作用下,连盐高速公路饱和软粘土的轴向累计应变、孔隙水压力和轴向周期应变软化的变化规律.实验结果表明:路堤中动应力和振动位移随行车速度和车重的增加而增加,随深度的增加而降低,有效影响深度达2.5 m;原状土的临界循环应力比远大于重塑土,承受循环应力能力高于重塑土.因此,要加强浅层路基强度,同时要减少对底部下卧层软粘土的扰动.其结果可为在软土地基上设计和施工低路堤高速公路提供有益的参考. 相似文献
110.
设R是有限链环,R上长度为n的线性码C等同于模Rn的子模,循环码等同于R[x]/(xn-1)的理想.定义C[γi]={x|x∈C,γix=0},那么C[γi]是Rn的子模,且C[γi]/C[γi-1]是自由模.进一步当C是循环码时,C[γi]/C[γi-1]同构于K[x]/(xn-1)的某个理想.由此出发,给出了有限链环上线性码的结构和循环码的结构,证明并拓广了Norton的有关结论. 相似文献