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61.
62.
O. P. Ermolaev 《Journal of Applied Spectroscopy》1997,64(4):493-496
This study was carried out to investigate low-temperature (T=4.2 K) photoluminescence caused by interdopant recombination
transitions in n-germanium irradiated by fast (epicadmium) reactor neutrons and subjected to “complete” annealing (+450°C,
24 h). It is shown that lines of interdopant radiative recombination observed in initial and in irradiated and annealed specimens
are caused by both initial impurities and (mainly) dopants (As and Ga) implanted by transmutation as well as by defect sets
stable at long-time high-temperature annealing that do not contain fine dopants.
Belarusian State University, 4, F. Skorina Ave., Minsk, 220050, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 64, No. 4, pp. 479–482, July–August, 1997. 相似文献
63.
Yao S Xiong Y Wang W Driess M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(17):4890-4895
The first isolable pyridine‐stabilized germanone has been prepared and its reactivity toward trimethylaluminum has been investigated. The germanone adduct results from a stepwise conversion that starts from 4‐dimethylaminopyridine (DMAP) and the ylide‐like N‐heterocyclic germylene LGe: (L=CH{(C?CH2)(CMe)[N(aryl)]2}, aryl=2,6‐iPr2C6H3) ( 1 ) at room temperature, and gives the corresponding germylene–pyridine adduct L(DMAP)Ge: ( 2 ) in 91 % yield. The latter reacts with N2O at room temperature to form the desired germanone complex L(DMAP)Ge?O ( 3 ) in 73 % yield. The Ge? O distance of 1.646(2) Å in 3 is the shortest hitherto reported for a Ge?O species. The reaction of 3 with trimethylaluminum leads solely to the addition product LGe(Me)O[Al(DMAP)Me2] ( 4 ). The latter results from insertion of the Ge?O subunit into an Al? Me bond of AlMe3 and concomitant migration of the DMAP ligand from germanium to the aluminum atom. Compounds 2 – 4 have been fully characterized by analytical and spectroscopic methods. Their molecular structures have been established by single‐crystal X‐ray crystallographic analysis. 相似文献
64.
65.
A dye‐sensitized solar cell (DSSC) containing a TiO2 film treated with COOH‐functionalized germanium nanoparticles (Ge COOH Nps) exhibited a higher short‐circuit photocurrent density (Jsc; 15.4 mA cm−2) compared to the corresponding untreated DSSC (13.4 mA cm−2) using N719 and a 12 μm thick TiO2 film at 100 mW cm−2. The amount of N719 attached to the treated TiO2 film was 21 % greater than that attached to the untreated TiO2 film. Enhancement of the Jsc value by 15 % was attributed mostly to an intramolecular charge transfer from N719 attached to the Ge COOH Nps to the TiO2 conduction band through the Ge COOH Nps. 相似文献
66.
A new setup has been recently developed in the toroidal opposed-anvil device ‘Conac 40’ to perform differential thermal analysis in a high pressure range (0–6 GPa). To evaluate the precision and the reliability of the setup, the high pressure melting curve of germanium and the transition points of α-iron have been investigated up to 5.3 GPa and compared with previous results. 相似文献
67.
Bianca Haberl Jamie J. Molaison Joerg C. Neuefeind Luke L. Daemen Reinhard Boehler 《高压研究》2013,33(3):426-437
ABSTRACTA simple modified Bridgman design for large volume pressure anvils usable in the Paris-Edinburgh (PE) press has been demonstrated at Oak Ridge National Laboratory Spallation Neutron Source. The design shows advantages over the toroidal anvils typically used in the PE press, mainly rapid compression/decompression rates, complete absence of blow-outs upon drastic phase transitions, simplified cooling, high reliability, and relative low loads (~40 tons) corresponding to relatively high pressures (~20?GPa). It also shows advantages over existing large-volume diamond cells as sample volumes of ~2–3?mm3 can be easily and rapidly synthesized. The anvils thus allow sample sizes sufficient for in situ neutron diffraction as well as rapid synthesis of adequate amounts of new materials for ex situ analysis via total neutron scattering and neutron spectroscopy. 相似文献
68.
针对非晶硅锗电池本征层高锗含量时界面带隙失配以及高界面缺陷密度造成电池开路电压和填充因子下降的问题,通过在PI界面插入具有合适带隙的非晶硅缓冲层,不仅有效缓和了带隙失配,降低界面复合,同时也通过降低界面缺陷密度改善内建电场分布,从而提高了电池的收集效率. 进一步引入IN界面缓冲层以及对非晶硅锗本征层进行能带梯度设计,在仅采用Al背电极时,单结非晶硅锗电池转换效率达8.72%.
关键词:
非晶硅缓冲层
非晶硅锗薄膜太阳电池
带隙
界面 相似文献
69.
70.
A. T. Naveed M. Q. Huda K. F. Abd El-Rahman J. Hartung J. H. Evans-Freeman A. R. Peaker D. C. Houghton C. Jeynes W. P. Gillin 《Journal of luminescence》1998,80(1-4):381-386
Strained Si1−xGex/Si quantum wells have been doped with erbium by implantation. A comparison is made with strained Si1−xGex/Si quantum wells and relaxed Si1−xGex, with x between 10% and 25%, doped with erbium during MBE growth. The erbium concentration was between 1×1018 and 5×1018 cm−3 throughout the active regions. Transmission electron microscopy, X-ray diffraction, and photoluminescence studies indicate that good regrowth can been achieved after full amorphisation by implantation of the strained quantum wells. The erbium luminescence is more intense in the Si1−xGex/Si layers, but erbium-implanted samples containing Si1−xGex exhibit defect luminescence in the region of 0.9–1.0 eV. These defects are also present when Si1−xGex/Si quantum wells are implanted with an amorphising dose of silicon, and then regrown. They are attributed to small germanium-rich platelets, rather than to erbium-related defects. Electroluminescence is presented from a forward biased erbium-implanted Si0.87Ge0.13/Si structure at a drive current density of only 1.8 mA/cm2. 相似文献