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151.
Summary The synthesis and characterization of the complexes from the reactions of trichloro(cyclopentadienyl)titanium(IV) with 1,5-diarylthiocarbazones (aryl=phenyl,o-tolyl,o-chlorophenyl,p-tolyl,p-chlorophenyl, or 3,5-dimethylphenyl) are reported. They are of the types CpTi(HDz)Cl2 and CpTi(HDz)2Cl (Cp=cyclopentadienyl, HDz–=the mono-anion of a 1,5-diarylthiocarbazone, H2Dz). The compounds are nonelectrolytes in dimethylformamide (DMF). In solid state, the far i.r. spectra of CpTi(HDz)Cl2 indicate the complexes to be dimeric, involving Cl-bridges. 相似文献
152.
A simple, straightforward and efficient methodology is described for the synthesis of polysubstituted tetrahydropyridine via one-pot multicomponent reaction of β-ketoester, aldehyde and aniline in presence of catalytic amount of graphene oxide in acetonitrile. Graphene oxide is a versatile carbocatalyst and this is the first report on its application in a five component reaction. Good yield, usage of readily available starting material, operational simplicity, easy work-up and eco-friendly re-usable catalyst are the key features of this protocol. 相似文献
153.
Laser induced damage studies in mercury cadmium telluride 总被引:1,自引:0,他引:1
We have investigated laser induced damage at laser wavelength in diamond paste polished (mirror finish) and carborundum polished Hg0.8Cd0.2Te (MCT) samples with increasing fluence as well as number of pulses. Evolution of damage morphology in two types of samples is quite different. In case of diamond paste polished samples, evolution of damage morphological features is consistent with Hg evaporation with transport of Cd/Te globules towards the periphery of the molten region. Cd/Te globules get accumulated with successive laser pulses at the periphery indicating an accumulation effect. Real time reflectivity (RTR) measurement has been done to understand melt pool dynamics. RTR measurements along with the thermal profile of the melt pool are in good agreement with thermal melting model of laser irradiated MCT samples. In case of carborundum polished samples, laser damage threshold is significantly reduced. Damage morphological features are significantly influenced by surface microstructural condition. From comparison of the morphological features in the two cases, it can be inferred that laser processing of MCT for device applications depends significantly on surface preparation conditions. 相似文献
154.
Alverson G Baker WF Ballocchi G Benson R Berg D Blusk S Bromberg C Brown D Carey D Chand T Chandlee C Choudhary BC Chung WH de Barbaro L DeSoi W Dlugosz W Dunlea J Easo S Engels E Faissler W Fanourakis G Ferbel T Garelick D Ginther G Glass G Glaubman M Gutierrez P Hartman K Huston J Johnstone C Kapoor V Kourbanis I Lanaro A Lirakis C Lobkowicz F Lukens P Mani S Maul A Mansour J Miller R Nelson CA Oh B Orris D Pothier E Prebys E Rajaram BM Roser R Ruddick K Shepard P Shivpuri RK Sinanidis A 《Physical review letters》1992,68(17):2584-2587
155.
In this paper a homogeneous model for surface roughness in the identical double layer system has been presented. It has been shown that the reflectance change in non-absorbing layers is directly proportional to the square of the total thickness of the layers. In an absorbing layer, it has been shown that the thickness of each layer is equal to the surface roughness of the identical double layer system. The extinction coefficients of both layers are directly proportional to the thickness of that layer. 相似文献
156.
Formations of triplet state, molecular cation radical, and phenoxyl radical of 3,4‐methylenedioxy phenol (sesamol, SOH) in organic solvents have been investigated by laser photolysis as well as pulse radiolysis techniques. Photolysis of SOH in cyclohexane has been found to produce both triplet state (λmax ~ 480 nm) and phenoxyl radical (425–430 nm) of SOH by mono‐photonic processes. However, radical cation (λmax = 450 nm) and phenoxyl radical of SOH have been observed on radiolysis in cyclohexane. Further, radiolysis of SOH in benzene has been found to produce phenoxyl radical only. Mechanism of phenoxyl radical formation by photo‐excitation of SOH has been studied and triplet energy level of SOH is estimated to lie between 1.85 and 2.64 eV. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
157.
Summary Samples of nickel wires were aged at low temperature, then subjected to hydrogen diffusion electrolytically. Thermomagnetic
effect was measured both before and after hydrogenation. The latter samples show a more regular variation than the former
ones (without hydrogenation), indicating that the hydrogen-treated samples are electrically more homogeneous due to the presence
of hydrogen trapped at some lattice sites.
Riassunto Campioni di fili di nickel sono invecchiati a bassa temperatura e quindi sottoposti a diffusione di idrogeno elettrolitica. L’effetto termomagnetico è stato misurato sia prima che dopo l’idrogenazione. Questi ultimi mostrano una piú regolare variazione che i precedenti (senza idrogenazione), indicando che i campioni idrogenati sono elettricamente piú omogenei a causa della presenza di idrogeno intrappolato in alcuni loci del reticolo.
Резюме Образцы никелевой проволоки стареют при низких температурах, а затем подвергаются электролитически диффузии водорода. Измеряется термомагнитный эффект до и после гидрогенизации. Образцы после гидрогенизации обнаруживают более регулярные изменения, чем образцы до гидрогенизации, что указывает на то, что гидрогенизированные образцы электрически более однородные, вследствие наличия водорода, захваченного в некоторые узлы решетки.相似文献
158.
Relationship among glottal area, static supraglottic compression, and laryngeal function studies in unilateral vocal fold paresis and paralysis 总被引:1,自引:0,他引:1
Steven Bielamowicz Ritu Kapoor Jerome Schwartz Sheila V. Stager 《Journal of voice》2004,18(1):138-145
In this study, we evaluated the relationship between laryngeal function measures and glottal gap ratio and normalized measures of supraglottic behaviors in patients with unilateral vocal fold paresis (UVFP). Thirty-one patients were found to have unilateral vocal fold paresis by videoendoscopy and laryngeal electromyography, and 13 controls participated in this study. Patients with UVFP demonstrated significantly larger glottal gap ratios (p = 0.016) than control subjects. The nonparalyzed or contralateral vocal fold was associated with significantly more static false vocal fold compression (p = 0.03) compared with the paralyzed vocal fold or with the controls. Patients with unilateral vocal fold paresis were divided into subgroups: those with normal or abnormal maximum phonation time, flow, or pressure measures. Smaller glottal gap ratios were identified in patients with normal maximum phonation times and flow measures. Greater false vocal fold activity was identified in unilateral vocal fold paresis patients with normal laryngeal function measures than in unilateral vocal fold paresis patients with abnormal measures. These findings suggest that some patients with documented unilateral paresis and glottal incompetence can compensate for vocal fold weakness such that their acoustic and aerodynamic measures are normal. 相似文献
159.
Fragment angular distributions in heavy ion-induced fission reactions have been analysed in terms of a two component model—fission
following compound nucleus formation and fast fission events. It is seen that, contrary to the general assumption, fast fission
competes with compound nucleus fission even when the composite system is formed with a spin less than the rotating liquid
drop model limit for vanishing fission barrier. 相似文献
160.
The damage morphology of GaAs1 0 0 single crystal following femtosecond laser (wavelength 806 nm, pulse duration 110 fs, prf 10 Hz) excitation was studied as a function of laser fluence and number of pulses. The threshold value for damage to occur in a GaAs surface in the present experiment was 1.3×1014 W/cm2 for a single pulse. The cooling rate for threshold fluence was calculated as 2.22×1014 °C/s. The damage occurred in the form of surface removal. Ripples and grains were formed in the removed surface. At higher fluences micron depth pits were also formed. The damage morphology was explained with the help of Boson-condensation hypothesis. 相似文献