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151.
152.
A commutative fusion algebra is proved to be amenable if and only if the associated regular representation is bounded. 相似文献
153.
The crosscap number of a knot in the 3-sphere is defined as the minimal first Betti number of non-orientable surfaces bounded by the knot. In this paper, we determine the crosscap numbers of a large class of pretzel knots. The key ingredient to obtain the result is the algorithm of enumerating all essential surfaces for Montesinos knots developed by Hatcher and Oertel. 相似文献
154.
Onishi Yoshito Seo Yoshiho Matsuoka Masaoki Serikawa Shigeru Tsugane Ken 《Optical Review》2022,29(5):409-419
Optical Review - Machine vision system has great significance for the automatic inspection to enhance unclear defects. For the purpose of the improvement of the recognition accuracy in the... 相似文献
155.
Dr. Chong Liu Hiroe Kubota Takehiro Amada Dr. Kenichi Kon Dr. Takashi Toyao Dr. Zen Maeno Dr. Kakuya Ueda Dr. Junya Ohyama Prof. Atsushi Satsuma Takuya Tanigawa Dr. Nao Tsunoji Prof. Tsuneji Sano Prof. Ken-ichi Shimizu 《ChemCatChem》2020,12(11):3050-3059
The selective catalytic reduction of NO with ammonia (NH3−SCR) catalyzed by Cu−CHA zeolites is thoroughly investigated using in situ spectroscopic experiments combined with on-line mass spectroscopy (MS) under steady-state NH3−SCR conditions and transient conditions for Cu(II)/Cu(I) redox cycles. Quantitative analysis of the in situ XANES spectra of Cu−CHA under steady-state conditions of NH3−SCR show that NH3-coordinated Cu(II) species is the dominant Cu species at low temperatures (100–150 °C). At higher temperatures, Cu(II) species and [Cu(NH3)2]+ complex coexist, possibly because the rate of the Cu(II)→Cu(I) reduction step is comparable to that of the Cu(I)→Cu(II) oxidation step. In situ XANES, IR/MS, and UV-vis/MS experiments on the reduction half cycle demonstrate that the reduction of Cu(II) species occurs via the reaction of NH3-liganded Cu(II) with NO to yield N2 and H2O. For the oxidation half cycle, in situ XANES experiments of Cu(I) oxidation in 10 % O2 at 200 °C indicate that an increased density in CHA zeolite exhibits a higher oxidation rate. In situ UV-vis experiments of Cu(I) reoxidation using different mixtures of oxidant feed gas demonstrate the key role of O2 in the oxidation cycle. It is suggested that the reoxidation of Cu(I) to Cu(II) species occurs with only O2 as the oxidant, and a high Cu density in CHA zeolite promotes SCR activity by enhancing the oxidative activation of Cu(I) to Cu(II) during the catalytic cycle. 相似文献
156.
157.
The synthesis of a series of hydrosilylboronates via the selective iridium- or nickel-catalyzed monoborylation of dihydrosilane Si–H bonds is described. The synthesized silylboronates, which bear a single Si–H bond, can be used as novel silicon nucleophiles in the presence of transition-metal catalysts or bases. The first 29Si{1H} NMR spectroscopic evidence for the formation of (t-Bu)2HSiLi, generated by the reaction of (t-Bu)2HSi–B(pin) with MeLi, is reported as the first example of a dialkylhydorosilyl lithium species.Monoborylation of a dihydrosilane Si–H bond can be achieved in the presence of iridium- or nickel-based catalysts, yielding novel hydrosilylboronates that bear a hydrogen atom at the silicon center. 相似文献
158.
Petko St. Petkov Kristina Simeonova Iskra Z. Koleva Hristiyan A. Aleksandrov Yoshihiro Kubota Satoshi Inagaki Valentin Valtchev Georgi N. Vayssilov 《Molecules (Basel, Switzerland)》2021,26(23)
We used computational modeling, based on Density Functional Theory, to help understand the preference for the formation of silanol nests and the substitution of Si by Ti or Al in different crystallographic positions of the MSE-type framework. All these processes were found to be energetically favorable by more than 100 kJ/mol. We suggested an approach for experimental identification of the T atom position in Ti-MCM-68 zeolite via simulation of infrared spectra of pyridine and acetonitrile adsorption at Ti. The modeling of adsorption of hydrogen peroxide at Ti center in the framework has shown that the molecular adsorption was preferred over the dissociative adsorption by 20 to 40 kJ/mol in the presence or absence of neighboring T-atom vacancy, respectively. 相似文献
159.
Dr. Atsuko Masuya-Suzuki Satoshi Goto Takafumi Kambe Dr. Ryunosuke Karashimada Dr. Yasuhiro Kubota Prof. Nobuhiko Iki 《ChemistryOpen》2021,10(1):46-55
We prepared Ln(III) (Ln=Eu, Gd, and Yb) complexes with a tripodal Schiff base, tris[2-(5-methylsalicylideneimino)ethyl]amine (H3L) and studied their photophysical properties. Upon ligand excitation, YbL showed Yb(III)-centered luminescence in the near-infrared region. While the overall quantum yield (0.60(1)%) of YbL in acetonitrile was moderate among the reported values for Yb(III) complexes, its radiative lifetime (0.33(2) ms) was significantly shorter than those reported previously. We propose that the ligand-to-metal charge-transfer (LMCT) state mediated the sensitization in YbL. The emission and excitation spectra of EuL indicated the participation of the LMCT state in the sensitization. The radiative lifetime (0.84(7) ms) for EuL in the solid state was rather short compared to those of reported Eu(III) complexes. Our results show that the Yb(III) complex with the Schiff base ligand has two features: the short radiative lifetime and the non-triplet sensitization path. 相似文献
160.
Dr. Ryoichi Tatara Takuma Umezawa Prof. Kei Kubota Prof. Tatsuo Horiba Rena Takaishi Kazuo Hida Takashi Matsuyama Dr. Satoshi Yasuno Prof. Shinichi Komaba 《ChemElectroChem》2021,8(22):4345-4352
The combination of synthetically modified styrene-butadiene rubber (SBR) and sodium carboxymethyl cellulose (CMC) was studied as an aqueous binder for LiCoO2 composite electrodes under high-voltage operation. Methyl methacrylate (MMA) and 2-vinylpyridine (VP) substituted SBR copolymers were synthesized and examined as functional polymer binders. The electrolyte-solvent uptake of the binder-polymer film was increased by the introduction of the MMA units, but the solubility of the polymer in the solvent remained negligibly low. Hard-X-ray photoelectron spectroscopy revealed the formation of a relatively thick passivation layer on the LiCoO2 surface with MMA-substituted SBR and CMC binder, which suppressed the self-discharge of 4.5 V-charged LiCoO2. The capacity retention during battery cycling experiments was similar for the LiCoO2 electrodes with MMA-modified and unmodified SBR binders. While the effect of VP-substitution was not significant, incorporation of the MMA unit enhanced the stability of the charged LiCoO2 electrode and provided improved self-discharge performance. 相似文献