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61.
The reaction of bisgermavinylidene [(Me3SiN?PPh2)2C?Ge→Ge?C(PPh2?NSiMe3)2] ( 1 ) with AdNCO (Ad = Adamantyl) afforded the [2 + 2] cycloadditon product [(Me3SiN?PPh2)2CGeC(O) NAd] ( 2 ). Similar reaction of 1 with Ph3SiOH in tetrahydrofuran (THF) yielded the base‐stabilized germanium(II) triphenylsiloxide [H2C(PPh2?NSiMe3)2Ge(OSiPh3)2] ( 3 ). The results suggested that reactive germavinylidene may exist in solution and is capable of forming addition reaction products. The X‐ray structures of 2 and 3 were determined. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
62.
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64.
Dipankar Mishra Subhendu Naskar Shyamal K. Chattopadhyay Milan Maji Parbati Sengupta Rupam Dinda Saktiprasad Ghosh Thomas C. W. Mak 《Transition Metal Chemistry》2005,30(3):352-356
The synthesis, crystal structure, redox and spectroscopic properties of trans-[Ru(bbpH2)(PPh3)2Cl]Cl are reported. In the crystalline solvate trans-[Ru(bbpH2)(PPh3)2cCl]Cl CHCl3 H2O, the molecular components are connected by strong intermolecular hydrogen bonding to form an infinite double column. 相似文献
65.
B R Feiring T C P Sasfri V M Rao Tummala R W Mak 《The Journal of the Operational Research Society》1998,49(12):1249-1253
The quality history of individual parts from a critical operation can be modeled by a five-state Markov chain involving factory rework operation, customer inspection and field test, parts scrapped, parts defective but used-as-is by concession or re-graded for alternative applications, and defect-free parts satisfying customer requirements. We estimate total failure cost by a five-state Markov chain model and present a case study to demonstrate relationship of the total failure cost to appraisal and prevention costs. 相似文献
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67.
Antipenko B. M. Vikhrov M. N. Mak A. A. Pis'mennyi V. A. Polikarpova V. N. Tomashevich Yu. V. 《Journal of Applied Spectroscopy》1978,29(2):921-926
Journal of Applied Spectroscopy - 相似文献
68.
G.C. Ball T.K. Alexander W.G. Davies J.S. Forster I.V. Mitchell J. Keinonen H.B. Mak 《Nuclear Physics A》1982,386(2):333-345
Mean lifetimes of levels in 18F have been measured using the Doppler-shift attenuation method and the inverse reaction 3He(16O, p)18F. Targets of 3He implanted into Al, Nb, and Au foils were employed in the measurements. The Doppler-broadened lineshapes observed at 0° to the beam were analyzed to obtain the following lifetime values: 0.971 ± 0.030, 0.605 ± 0.029 and 0.435 ± 0.041 ps for the 1.70(1+), 2.52(2+) and 3.36(3+)MeV members of the Kπ = 1+ rotational band, 5.12 ± 0.56, 0.403 ± 0.018 and 1.91 ± 0.17 ps for the 2.10(2?), 3.13(1?) and 3.79(3?) MeV members of the Kπ = 0? bands, and 〈1.2, 2.7+4.1?2.7 and 20 ± 2 fs for the 3.06(2+, T = 1), 3.72(1+) and 3.84(2+) MeV states, respectively. 相似文献
69.
L. F. Pender H.-B. Mak H. J. Wintle 《Journal of Polymer Science.Polymer Physics》1983,21(9):1635-1646
We show that the Rutherford backscattering technique is very useful for studying the kinetics of diffusion processes in polymers. We have measured the diffusion of iodine into low-density polyethylene (LDPE) by optical absorbance and by Rutherford backscattering. The optical results appear to be normal, and show no electric field dependence, but the backscattering results reveal that this is misleading, because there is fast diffusion in the bulk accompanied by large surface concentrations of iodine. We have studied PET by the backscattering technique, and in this case the behavior corresponds to a weakly concentration-dependent diffusion coefficient with no observable surface effects. Neither set of results gives support to the domain theories of low-frequency electrical oscillation in these materials. 相似文献
70.
CM Thaker S Rayaprol Krushna Mavani DS Rana MS Sahasrabudhe SI Patil DG Kuberkar 《Pramana》2002,58(5-6):1035-1039
The effect of simultaneous substitution of a fluctuating cation and a divalent cation in LaMnO3 perovskite modifies the properties of the material to exhibit large valence colossal magnetoresistance (CMR) effect. A good
example of these properties is (La1−2x
Pr
x
Ca
x
)MnO3 (LPCMO) type CMR material. In this communication it is reported that, with the increase in x (for x=0.1, 0.15, 0.2), the T
c varies between 100 and 120 K with improvisation in metal-insulator transition. Interestingly, resistance increases with x from few hundred ohms to few kilo ohms with corresponding decrease in the unit cell volume. The results of the studies using
X-ray diffraction (XRD), electrical resistivity, magnetoresistance and ac susceptibility measurements on LPCMO samples for
understanding the structural, transport and magnetic properties are discussed in detail. 相似文献