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101.
Thomas G. Gray 《ChemInform》2009,40(18):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
102.
103.
New Phosphorus-bridged Transition Metal Carbonyl Complexes. The Crystal Structures of [Re2(CO)7(PtBu)3], [Co4(CO)10(PtBu)2], [Ir4(CO)6(PtBu)6], and [Ni4(CO)10(PiPr)6], (PtBu)3 reacts with [Mn2(CO)10], [Re2(CO)10], [Co2(CO)8] and [Ir4(CO)12] to form the multinuclear complexes [M2(CO)7(PtBu)3] (M = Re ( 1 ), Mn ( 5 )), [Co4(CO)10(PtBu)2] ( 2 ) and [Ir4(CO)6(PtBu)6] ( 3 ). The reaction of (PiPr)3 with [Ni(CO)4] leads to the tetranuclear cluster [Ni4(CO)10(PiPr)6] ( 4 ). The complex structures were obtained by X-ray single crystal structure analysis: ( 1 : space group P1 (Nr. 2), Z = 2, a = 917.8(3) pm, b = 926.4(3) pm, c = 1 705.6(7) pm, α = 79.75(3)°, β = 85.21(3)°, γ = 66.33(2)°; 2 : space group C2/c (Nr. 15), Z = 4, a = 1 347.7(6) pm, b = 1 032.0(3) pm, c = 1 935.6(8) pm, β = 105.67(2)°; 3 : space group P1 (Nr. 2), Z = 4, a = 1 096.7(4)pm, b = 1 889.8(10)pm, c = 2 485.1(12) pm, α = 75.79(3)°, β = 84.29(3)°, γ = 74.96(3)°; 4 : space group P21/c (Nr. 14), Z = 4, a = 2 002.8(5) pm, b = 1 137.2(8) pm, c = 1 872.5(5) pm, β = 95.52(2)°). 相似文献
104.
105.
A. Liem D. Nickel J. Limpert H. Zellmer U. Griebner S. Unger A. Tünnermann G. Korn 《Applied physics. B, Lasers and optics》2000,71(6):889-891
We report on a high-gain diode-pumped ytterbium-doped fiber-amplifier system delivering pulse energies in the 100-μJ range
at high repetition rates (32 kHz) with nearly-diffraction-limited beam quality (M2∼1.7) at a 1060-nm center wavelength. Femtosecond seed-laser pulses are stretched in a commercially available single-mode
fiber and compressed after amplification to subpicosecond pulse duration. In a multimode Yb-doped fiber amplifier we have
demonstrated average powers of up to 22 W and single-pulse energies of up to 130 μJ.
Received: 16 August 2000 / Revised version: 4 September 2000 / Published online: 8 November 2000 相似文献
106.
B.C. Li W. Theobald E. Welsch R. Sauerbrey 《Applied physics. B, Lasers and optics》2000,71(6):819-826
We performed calculations for a chirped-pulse-amplification laser system with a sub-100-fs pulse duration including the finite
size of gratings in an aberration-free stretcher/compressor design. Both the higher-order phase dispersion and the spectral
clipping, which is due to the finite size of the optics in the stretcher and the compressor, are taken into account in the
calculation. We discuss the influence of both phase dispersion and spectral clipping on the important parameters of the recompressed
pulse, such as pulse duration, pulse contrast, and peak intensity, employing different phase-dispersion compensation methods.
The calculations show that the use of a small compressor grating reduces the higher-order phase errors and smoothes the sharp
spectral cut-off caused by spectral clipping in the stretcher, which consequently improves the pulse contrast ratio of the
main pulse to the pedestal.
Received: 1 April 2000 / Published online: 8 November 2000 相似文献
107.
V. Rizzi G. Viesti D. Bazzacco A. Algora-Pineda D. Appelbe G. de Angelis N. Belcari M. Cinausero M. De Poli T.E. Drake A. Gadea A. Galindo-Uribarri N. Gelli D. Fabris E. Farnea E. Fioretto W. Krolas T. Kroll F. Lucarelli S. Lunardi M. Lunardon T. Martinez R. Menegazzo B.K. Nayak G. Nebbia D.R. Napoli B. Nyakó C. Petrache Zs. Podolyák G. Prete C. Rossi Alvarez A. Samant P. Spolaore C. Ur K. Zuber 《The European Physical Journal A - Hadrons and Nuclei》2000,7(3):299-301
The ridge structure with ΔEγ=±30 keV, observed in the past in coincidence with protons emitted in the reaction 187 MeV 37Cl +120Sn and attributed to an hyperdeformed nuclear shape in 152Dy, has been studied in a new experiment performed with the EUROBALL III array. The ridge is now observed in coincidence with
transitions in the yrast superdeformed band of 152Dy but no discrete rotational bands have been identified.
Received: 7 February 2000 相似文献
108.
R.P. Singh R.K. Bhowmik S.S. Ghugre S.B. Patel 《The European Physical Journal A - Hadrons and Nuclei》2000,7(1):35-40
High spins states in 99Rh were populated via the 66Zn(37Cl, 2p2n)99Rh reaction at an incident beam energy of 130 MeV. Seventeen new transitions have been observed in the present study and the
level scheme has now been extended up to a spin of J∼ 25ħ and an excitation energy of about E
x∼ 10 MeV. The observation of a positive parity E2 cascade based on the 9/2+ isomeric level is suggestive of collective behaviour in this nucleus up to high spins. Spherical shell model (within restricted
model space) and Cranked shell model calculations were performed to obtain an insight into the observed level structure. The
new collective band observed up to a spin of J∼ 25ħ is suggested to be based on (πg
9/2
3) ⊗ (νg
7/2
2) quasi-particle excitations.
Received: 12 July 1999 / Revised version: 14 September 1999 相似文献
109.
1INTRODUCTIONHomo dinuclearmetalcarbonylclustershavebenstudiedwidelyfortheirnovelstructuresandusesinorganicsynthesis〔1〕.Examp... 相似文献
110.
Tadashi Kawai Keiichiro Shiga Takehiko Suzuki Tomokazu Iyoda 《Journal of molecular catalysis. A, Chemical》1999,140(3):15-292
Tetravinylsilane and divinylsilanes have been successfully metathesized for the first time over Re2O7/Al2O3 catalyst promoted with tetrabutyltin under mild reaction conditions. All of the products were acyclic oligomers via intermolecular metathesis; the cyclic products via intramolecular metathesis were not formed. 相似文献