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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.
~(186,188)Re具有优良的核素性质,是放射性治疗药物的首选核素之一~([1]).~(186,188)Re广泛用于有机小分子化合物,单抗(McAb)、单抗片段(Fab)、受体配基和生物小分子肽,以达到靶向治疗的目的~([2-3]).铼的化学性质与锝极其相似,在标记前以~(188)ReO_4~-形式存在,在标记药物中呈低价态.制备时常规方法是将七价铼通过亚锡法还原到五价~([4-5]).  相似文献   
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.
High average power ultra-fast fiber chirped pulse amplification system   总被引:2,自引:0,他引:2  
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.
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.
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.
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.
Lü Kai 《结构化学》1999,18(2):114-118
1INTRODUCTIONHomo dinuclearmetalcarbonylclustershavebenstudiedwidelyfortheirnovelstructuresandusesinorganicsynthesis〔1〕.Examp...  相似文献   
110.
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   
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