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101.
Validation of Ozone Monitoring Instrument UV Satellite Data Using Spectral and Broadband Surface Based Measurements at a Queensland Site 下载免费PDF全文
Mustapha A. A Jebar Alfio V. Parisi Nathan J. Downs Joanna F. Turner 《Photochemistry and photobiology》2017,93(5):1289-1293
This research reconstructed and validated the broadband UVA irradiances derived from discrete spectral irradiance data retrieved from the Ozone Monitoring Instrument (OMI) satellite from 1 January to 31 December 2009. OMI data at solar noon were compared to ground‐based spectral irradiances at Toowoomba (27°36′ S 151°55′ E), Australia, at 310, 324 and 380 nm for both cloud‐free and all sky conditions. There was a strong relationship between the ground‐based UV spectroradiometer data and satellite‐based measurements with an R2 of 0.89 or better in each waveband for cloud‐free days. The data show an overestimate of the satellite‐derived spectral irradiances compared to the ground‐based data. The models developed for the subtropical site data account for this overestimation and are essential for any data correlation between satellite‐ and ground‐based measurements. Additionally, this research has compared solar noon broadband UVA irradiances evaluated with a model and the discrete satellite spectral irradiances for the solar noon values of cloud‐free days to those measured with a ground‐based UVA radiometer. An R2 of 0.86 was obtained confirming that for cloud‐free days the broadband UVA can be evaluated from the OMI satellite spectral irradiances. 相似文献
102.
C. R. Downs C. G. Stupp M. C. Boswell R. Ripan 《Analytical and bioanalytical chemistry》1931,85(1-3):101-102
103.
C. R. Downs C. G. Stupp M. C. Boswell und R. Ripan 《Fresenius' Journal of Analytical Chemistry》1931,85(1-3):101-102
Ohne Zusammenfassung 相似文献
104.
Hexiong Yang Justin Zwick Robert T. Downs Gelu Costin 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(10):i89-i90
This study presents the first structural report of natural isokite (calcium magnesium phosphate fluoride), with the formula CaMg(PO4)F0.8(OH)0.2 (i.e. some substitution of OH for F), based on single‐crystal X‐ray diffraction data. Isokite belongs to the C2/c titanite mineral group, in which Mg is on an inversion centre and the Ca, P and F/OH atoms are on twofold axes. The structure is composed of kinked chains of corner‐sharing MgO4F2 octahedra that are crosslinked by isolated PO4 tetrahedra, forming a three‐dimensional polyhedral network. The Ca2+ cations occupy the interstitial sites coordinated by six O atoms and one F anion. 相似文献
105.
T. R. Downs 《Fresenius' Journal of Analytical Chemistry》1923,62(10):394
Ohne Zusammenfassung 相似文献
106.
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108.
Thermal decomposition of monochlorogallane, [H2GaCl]n, at ambient temperatures results in the formation of subvalent gallium species. To Ga[HGaCl3], previously reported, has now been added a second mixed-valence solid, Ga4[HGaCl3]2[Ga2Cl6] (1), the crystal structure of which at 150 K shows a number of unusual features. Adducts of monochlorogallane, most readily prepared from the hydrochloride of the base and LiGaH4 in appropriate proportions, include not only the 1:1 molecular complex Me3P.GaH2Cl (2), but also 2:1 amine complexes which prove to be cationic gallane derivatives, [H2Ga(NH2R)2]+Cl-, where R = tBu (3a) or sBu (3b). All three of these complexes have been characterized crystallographically at 150 K. 相似文献
109.
Downs AJ Greene TM McGrady GS Townson N Brain PT Pulham CR Rankin DW Robertson HE Smart BA Alberts IL 《Inorganic chemistry》1996,35(24):6952-6958
The structures of gaseous CH(3)AsF(2) and (CH(3))(2)AsF have been determined by electron diffraction incorporating vibrational amplitudes derived from ab initio force fields scaled by experimental frequencies and, for the difluoride, restrained by microwave constants. The following parameters (r(alpha) degrees structure, distances in pm, angles in degrees) have been determined for CH(3)AsF(2): r(As-C) = 194.6(4), r(As-F) = 173.1(1), angleCAsF = 95.2(1), angleFAsF = 97.0(1). For (CH(3))(2)AsF structural refinement gives r(As-C) = 195.1(1), r(As-F) = 175.4(1), angleCAsF = 95.3(5), and angleCAsC = 96.9(8). For the series (CH(3))(3)As, (CH(3))(2)AsF, CH(3)AsF(2), and AsF(3), both As-C and As-F bond lengths are shortened with increasing numbers of F atoms, but the angles CAsF and FAsF are almost invariant. 相似文献
110.
Jason K. Vohs L. Ellen Downs Jessica Stasalovich Michael Barfield Gregory H. Robinson 《Journal of Cluster Science》2002,13(4):601-608
The synthesis and molecular structures of tris(pentamethylphenyl)aluminum, (C6Me5)3Al, (I), and the magnesium cluster [Mg6(
3-OH)2(
3-Br)2(
2-Br)8(OEt2)8] (II), are reported. Both compounds were isolated from the same system. The aluminum atom in (I) resides in an almost idealized trigonal planar environment. The dihedral angles of the pentamethylphenyl rings relative to the AlC3plane in (I) are 67.2, 62.4, and 61.2°. The neutral magnesium cluster, (II), is interesting in that contains six magnesium atoms each of which resides in octahedral environments. 相似文献