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991.
Inoue I Zheng B Watanabe K Ishikawa Y Shiba K Yasueda H Uraoka Y Yamashita I 《Chemical communications (Cambridge, England)》2011,47(47):12649-12651
Carbon nanotube-TiO(2) hybrid materials with many nano-scale cavities were realized using a bifunctional protein supramolecule possessing carbonaceous material-binding peptides and Ti-binding peptides. The obtained structure was confirmed to consist of a central nanotube, surrounding proteins, and a swathing titanium-layer. All processes were carried out at room temperature, using an environmentally friendly method. 相似文献
992.
Someya CI Inoue S Präsang C Irran E Driess M 《Chemical communications (Cambridge, England)》2011,47(23):6599-6601
Cationic and zwitterionic boryl bromide species and a borenium-boryl bromide cation have been synthesised which represent new N-donor stabilised cationic boron compounds with β-diketiminate ligands. The unexpected borenium-boryl bromide results from a head-to-tail dimerisation of the corresponding zwitterionic boryl bromide accompanied by proton migration. The electronic nature of these new species was studied by DFT calculations. 相似文献
993.
Nakashima Y Suzuki S Yamazaki M Inoue Y Fukatsu Y Yamamoto A 《Analytical sciences》2011,27(9):889-892
A quantitative analysis was developed for eight acidic and neutral preservatives in foods and daily necessities using the inline dialysis-IC combined with hydrophobic anion-exchange separation. The eight preservatives were dialyzed by inline dialysis and separated on a hydrophobic anion exchange column. Under the optimized separation conditions, the detection limits (S/N = 3) for the eight preservatives were from 0.08 to 0.66 mg L(-1), moreover, a good linearity (R(2) > 0.998) for each preservative was obtained in the range to 100 mg L(-1). Although the dialysis rate of the neutral preservatives was not so high, a good repeatability (RSD, n = 8) of less than 1.5% for the eight preservatives was obtained. The inline dialysis-IC method was applied to the determination of the preservatives in foods and daily necessities. The preservatives were quantified without any interference. The proposed method will be useful for the determination of the preservatives in foods and daily necessities containing high concentration matrices. 相似文献
994.
A novel hydrophilic stationary phase bonded with a zwitter-ionic polymer for HPLC was synthesized. The stationary phase, in combination with a mobile phase containing various salts, was evaluated for its ability to separate water-soluble compounds, such as nucleobases, nucleosides and glycosides. The retention of a large majority of the solutes, except for cytosine, was increased by adding anti-chaotropic ions to the mobile phase. These results suggested that the retention of solutes depended on the thickness of the hydration layer on the stationary phase. In the zwitter-ionic polymer adsorbent, the formation of the hydration layer and the ionicity of the zwitter-ionic group on the stationary phase will be controlled by the properties of the ions added to the mobile phase. 相似文献
995.
The effect of ultraviolet ray (UV) irradiation on the bonding strength between low carbon stainless steel 316 (SUS316L) and trisuccinimidyl citrate (TSC)-crosslinked alkali-treated gelatin (AlGelatin-TSC) was investigated. The UV irradiation effectively generated hydroxyl groups on the surface of SUS316L. The bonding strength between AlGelatin-TSC and SUS316L before UV irradiation was 0.345±0.007 MPa, and upon UV irradiation it increased to 0.750±0.069 MPa. In order to explain this enhanced bonding strength, the surface of SUS316L was examined using its water contact angle and X-ray photoelectron spectroscopy. Furthermore, the N 1s peaks derived from the TSC succinimidyl group were assigned to the surface of SUS316L after the immobilization of the TSC. This indicates that ester bond formation between the TSC active esters and the SUS316L hydroxyl groups contributed to the enhanced bonding strength. Therefore, UV irradiation and subsequent TSC immobilization is a simple way to functionalize biometal surfaces with various structures. This has practical applications for medical devices such as drug-eluting stents, dental implants, and metallic artificial bone. 相似文献
996.
Claudia Virués Zaira Domínguez Magali Salas Rosa Elena Navarro Enrique F. Velázquez Samuel Cruz Javier Hernández Motomichi Inoue 《Journal of inclusion phenomena and macrocyclic chemistry》2012,74(1-4):407-413
Host?guest complexation has been studied by 1H NMR on the benzyl and phenethyl amides of ferulic and caffeic acids as the guests in chloroform and acetonitrile; the counter host is a cyclophane which integrates four phenylene rings, amino and amide groups in the macrocyclic framework and bears four pendant methyl acetate ester arms. CAPE, one of the best known natural antioxidants, also has been studied for comparison. Among the guests studied, ferulic acid benzyl amide shows NMR shifts due to the formation of a host?guest complex in chloroform. The complexation occurs in two steps with the formation constants K 1?=?[HG]/[H][G]?=?6?M?1 and β 2?=?[HG2]/[H][G]2?=?87?M?2. Two guest molecules are bound on the surface of the macrocyclic framework of a host molecule by two hydrogen bonds, NH(host amide)···O=C(guest amide) and C=O(host ester)···HO(guest phenol). The latter hydrogen bond may protect the bioactive site, i.e., phenol OH, of guest molecules captured in the complex against undesirable oxidation. This feature is observed only for ferulic acid benzyl amide in chloroform; the cyclophane ester interacts with this amide, distinctively from the other hydroxycinnamic acid derivatives. 相似文献
997.
Won‐Sik Han Kyung‐Ryang Wee Hyun‐Young Kim Prof. Chyongjin Pac Yu Nabetani Daisuke Yamamoto Tetsuya Shimada Prof. Haruo Inoue Heesung Choi Prof. Kyeongjae Cho Prof. Sang Ook Kang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(48):15368-15381
Visible‐light‐driven H2 evolution based on Dye/TiO2/Pt hybrid photocatalysts was investigated for a series of (E)‐3‐(5′‐{4‐[bis(4‐R1‐phenyl)amino]phenyl}‐4,4′‐(R2)2‐2,2′‐bithiophen‐5‐yl)‐2‐cyanoacrylic acid dyes. Efficiencies of hydrogen evolution from aqueous suspensions in the presence of ethylenediaminetetraacetic acid as electron donor under illumination at λ>420 nm were found to considerably depend on the hydrophilic character of R1, varying in the order MOD (R1=CH3OCH2, R2=H)≈ MO4D (R1=R2=CH3OCH2)> HD (R1=R2=H)> PD (R1=C3H7, R2=H). In the case of MOD /TiO2/Pt, the apparent quantum yield for photocatalyzed H2 generation at 436 nm was 0.27±0.03. Transient absorption measurements for MOD ‐ or PD ‐grafted transparent films of TiO2 nanoparticles dipped into water at pH 3 commonly revealed ultrafast formation (<100 fs) of the dye radical cation (Dye.+) followed by multicomponent decays, which involve minor fast decays (<5 ps) almost independent of R1 and major slower decays with significant differences between the two samples: 1) the early decay of the major components for MOD is about 2.5 times slower than that for PD and 2) a redshift of the spectrum occurred for MOD with a time constant of 17 ps, but not for PD . The substituent effects on H2 generation as well as on transient behavior have been discussed in terms substituent‐dependent charge recombination (CR) of Dye.+ with electrons in bulk, inner‐trap, and/or interstitial‐trap states, arising from different solvent reorganization. 相似文献
998.
Bimala Pangeni Hari Paudyal Katsutoshi Inoue Hidetaka Kawakita Keisuke Ohto Shafiq Alam 《Cellulose (London, England)》2012,19(2):381-391
Novel utilization of cotton cellulose was developed by chemically modifying with concentrated sulfuric acid to prepare a novel
kind of adsorption gel for gold. The adsorption behaviors of the gel were investigated for various metals from acidic chloride
media. The gel was found to be highly selective for Au(III) over other precious and base metals tested over the whole concentration
range of hydrochloric acid. The maximum adsorption capacity for Au(III) was evaluated as 6.21 mmol/g at 303 K. The amount
of adsorbed Au(III) was increased with increasing temperature. A kinetic study for the adsorption of Au(III) at various temperatures
confirmed the endothermic adsorption process following pseudo-first order kinetics. The activation energy was evaluated as
78.8 kJ/mol. Interestingly, it was found that the adsorbed Au(III) was reduced to elemental form which was evidenced by the
clearly visible elemental gold particles which was further confirmed by means of the X-ray diffraction spectrum and optical
microscope image of the gel after the adsorption of Au(III). The mechanism of Au(III) adsorption on the cotton gel and its
reduction to elemental gold was proved from the results of IR-spectra. The main mechanism could be explained in terms of the
coordination of Au(III) to oxygen atom of C–O–C linkage of cross linked cotton gel and to the oxygen atoms of the hydroxyl
groups at C2 and C3 atoms of pyranose ring of cotton cellulose followed by the reduction to metallic gold. The adsorbed gold in the cotton gel
can easily be recovered by incineration. 相似文献
999.
Chiral recognition abilities of the title host for (R)- and (S)-α-methyl-4-nitrobenzylamine were examined in the ground and excited states to give a relative affinity (K(R)/K(S)) of 2.16 by spectral titration and a relative rate constant (k(R)/k(S)) of 2.23 by fluorescence quenching, revealing that the quenching process is static and not enantiodifferentiating. 相似文献
1000.
Fukui H Inoue Y Yamada T Ito S Shigeta Y Kishi R Champagne B Nakano M 《The journal of physical chemistry. A》2012,116(22):5501-5509
Metal-metal multiply bonded complexes in their singlet state have been predicted to form a novel class of "σ-dominant" third-order nonlinear optical compounds based on the results of dichromium(II) and dimolybdenum(II) systems (H. Fukui et al. J. Phys. Chem. Lett.2011, 2, 2063) whose second hyperpolarizabilities (γ) are enhanced by the contribution of the dσ electrons with an intermediate diradical character. In this study, using the spin-unrestricted coupled-cluster method with singles and doubles as well as with perturbative triples, we investigate the dependences of γ on the group and on the period of the transition metals as well as on their atomic charges in several open-shell singlet dimetallic systems. A significant enhancement of γ is observed in those dimetallic systems composed of (i) transition metals with a small group number, (ii) transition metals with a large periodic number, and (iii) transition metals with a small positive charge. From the decomposition of the γ values into the contributions of dσ, dπ, and dδ electrons, the γ enhancements are shown to originate from the dσ contribution, because it corresponds to the intermediate diradical character region. Furthermore, the amplitude of dσ contribution turns out to be related to the size of the d(z(2)) atomic orbital of the transition metal, which accounts for the dependence of γ on the group, on the period, and on the charge of the metal atoms. These dependences provide a guideline for an effective molecular design of highly efficient third-order nonlinear optical (NLO) systems based on the metal-metal bonded systems. 相似文献