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71.
72.
利用甲醇-氢(CH3OH-H2)混合气体为气源,30nm厚的无定形硅为过渡层,借助于微波等离子体化学气相沉积(MWCVD)成功地将金刚石薄膜生长在不锈钢上,其最低生长温度可至420℃,并且甲醇-氢混合气体比传统的甲烷-氢(CH4-H2)更具优势,测试表明这种金刚石薄膜有希望作为耐磨层在工业上应用 相似文献
73.
利用IOS近似模型,计算了星际分子云条件下E型CH3CN-H2含超精细能级的的碰撞跃迁速率系数。其温度范围是20K-140K。为研究分子云与恒星形成区的物理、化学性质提供了大量有用的基础分子数据。 相似文献
74.
We show that CH implies that , when equipped with the Vietoris topology, has a subspace which is an L-space and a subspace which is an S-space. This is an immediate consequence of the following purely combinatorial result: CH implies the existence of an ω1-sequence 〈xα: α < ω1〉 in such that (1) if α<β<ω1, then ; (2) if I ?ω1 is unaccountable, then there are distinct α, β ∈ I with Xβ ?Xα. 相似文献
75.
New Schiff's bases of theN-vinylimidazole andN-vinylbenzimidazole series were synthesized.1H NMR data suggest that the azomethines exist in theE-form with respect to the CH=N bond and that the vinyl groups havetrans-orientation relative to each other.
Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 1857–1859, October, 1997. 相似文献
76.
77.
采用连续可调谐二极管半导体激光器为探测光源,以可调怀特型长光程多通池(46.36~1158.90m)作为吸收池,采用直接吸收的方法,探测了室温下1.65μm附近CH4分子的高分辨率吸收光谱。在6043.00~6053.72cm-1范围内探测了5组不同压力和光程下的吸收光谱,观测到了259条线新的CH4分子吸收谱线,实验数据用Gaussian线型进行拟合,得到了这些吸收谱线的线强、线位置以及线强的标准偏差值,并对光谱中难以分辨的吸收谱线进行了分析。探测得到的最小谱线线强是4.3×10-27cm-1·(molcule·cm-2)-1,吸收谱线线强大于3.0×10-24cm-1·(mol·cm-2)-1由于吸收饱和而未被处理,同时所测得的光谱也显示出CH4分子在1.65μm附近有非常丰富的弱吸收谱线和复杂的结构。文中所报道的吸收谱线都是HITRAN2004数据库中所未报道的,而且也未见有其他文献报道过。 相似文献
78.
Increasing the stability of perovskite solar cells is one of the most important tasks in the photovoltaic industry. Thus, the structural, energetic, and electronic properties of pure CH3NH3PbI3 and fully doped compounds (CH3NH3PbBr3 and CH3NH3PbCl3) in cubic and tetragonal phases were investigated using density functional theory calculations. We also considered the effects of mixed halide perovskites CH3NH3PbI2X (where X = Br and Cl) and compared their properties with CH3NH3PbI3. The DFT results indicate that the phase transformation from tetragonal to cubic phase decreases the band gap. The calculated results show that the X‐site ion plays a vital role in the geometrical stability and electronic levels. An increase in the band gap and a reduction in the lattice constants are more apparent in CH3NH3PbI2X compounds (I > Br > Cl). 相似文献
79.
Experimental absorption spectra of benzene, isooctane, and their mixtures are obtained in the wavelength range λ = 1620–1820
nm in which the first overtones of vibrational frequencies of CH, CH2, and CH3 hydrocarbon groups are located. Positions of fundamental absorption bands of benzene are refined. Absorption spectra of benzene-isooctane
mixtures are shown to intersect in a narrow area near λ ≈ 1695 nm. The main maximum of benzene absorption at λ = 1671.5 ±
0.5 nm, where the influence of isooctane absorption is practically absent, is proposed for determining the content of benzene
in benzene-isooctane mixtures. A linear calibration curve for λ = 1671.5 nm that encompasses the full range of benzene concentrations
(0–100%) is presented.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 5, pp. 631–634, September–October, 2008. 相似文献
80.
Noboru Sato Yuichi Funato Yasuyuki Fukushima Takeshi Momose Mitsuo Koshi Yukihiro Shimogaki 《国际化学动力学杂志》2020,52(6):359-367
We established a gas-phase, elementary reaction model for chemical vapor deposition of silicon carbide from methyltrichlorosilane (MTS) and H2, based on the model developed at Iowa State University (ISU). The ISU model did not reproduce our experimental results, decomposition behavior of MTS in the gas phase in an environment with H2. Therefore, we made several modifications to the ISU model. Of the reactions included in existing models, 236 were lacking in the ISU model, and thus were added to the model. In addition, we modified the rate constants of the unimolecular reactions and the recombination reactions, which were treated as a high-pressure limit in the ISU model, into pressure-dependent rate expressions based on the previous reports (to yield the ISU+ model), for example, H2(+M) → H + H(+M), but decomposition behavior remained poorly reproducible. To incorporate the pressure dependencies of unimolecular decomposition rate constants, and to increase the accuracies of these constants, we recalculated the rate constants of five unimolecular decomposition reactions of MTS using the Rice-Ramsperger-Kassel-Marcus method at the CBS-QB3 level. These chemistries were added to the ISU+ model to yield the UT2014 model. The UT2014 model reproduced overall MTS decomposition. From the results of our model, we confirmed that MTS mainly decomposes into CH3 and SiCl3 at the temperature around 1000°C as reported in the several studies. 相似文献