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951.
By using the neutral bidentate nitrogen-containing ligands; bis(3,5-dimethyl-1-pyrazolyl)methane (L0″), bis(3,5-diisopropyl-1-pyrazolyl)methane (L1″), bis(3-tertiary-butyl-5-isopropyl-1-pyrazolyl)methane (L3″), and bis(3,5-ditertiary-butyl-1-pyrazolyl)methane (L4″), the copper(II) nitrato complexes [Cu(L0″)2(NO3)]NO3 (1NO3), [Cu(L0″)(NO3)2] (2), [Cu(L1″)(NO3)2] (3), [Cu(L3″)(NO3)2] (4), and [Cu(L4″)(NO3)2] (5), chloro complexes [Cu(L0″)2Cl]2(CuCl4) (6CuCl4), [Cu(L0″)2Cl]2(Cu2Cl6) (6Cu2Cl6), [Cu(L1″)Cl2] (7), and [Cu(L3″)Cl2] (8), nitrito complexes [Cu(L0″)(ONO)2] (9) and [Cu(L1″)(ONO)2] (10), and the complexes with perchlorate ions [Cu(L0″)2(CH3OH)](ClO4)2 (11ClO4) and [Cu(L1″)2(H2O)](ClO4)2 (12ClO4) were systematically synthesized and fully characterized by X-ray crystallography and by IR, far-IR, UV–Vis absorption, and ESR spectroscopy. In comparison with the obtained complexes with four bis(pyrazolyl)methanes having different bulkiness at pyrazolyl rings, the second coordination sphere effects on the ligands are discussed in detail. Moreover, the structures and physicochemical properties of these obtained complexes are compared with those of the related complexes with the neutral tridentate tris(pyrazolyl)methane ligand. 相似文献
952.
Yasunori MatsuiHayato Namai Ikuko Akimoto Ken-ichi Kan’noKazuhiko Mizuno Hiroshi Ikeda 《Tetrahedron》2011,67(38):7431-7439
Substituent effects on the energies of electronic transitions (ETs) between the triplet excited and ground states of gem-diphenyltrimethylenemethane biradicals (32a) were explored by using thermoluminescence (TL) spectroscopy and density functional theory (DFT) including time-dependent (TD) DFT. Linear free energy (Hammett) analyses of TL energies of a variety of para-substituted aryl derivatives of 32* gave reasonable correlations with the substituent constant, σ. The slope of Hammett plots of the data are nearly identical to one obtained from a similar analysis of the photoluminescence (PL) energies of the structurally-related 1,1-diarylethyl radicals (3*). The results suggest that TL of 32* and PL of 3* derive from a common diarylmethyl radical fluorophore. This interpretation is also supported by the DFT and TDDFT calculated electronic structures and ET energies of 32 and 3. Thermodynamic and kinetic analyses of the charge recombination (CR) process between 2+ and 1−, which generates 32*, revealed that substituents not only alter the TL energies but also the TL intensities of 32*. The observations made in this effort demonstrate that 32* as well as 32 and 2+ have greatly twisted molecular geometries and highly localized electronic structures. 相似文献
953.
Tatsuya Watari Jianhua Fang Kazuhiro Tanaka Hidetoshi Kita Ken-ichi Okamoto Tetsuji Hirano 《Journal of membrane science》2004,230(1-2):111-120
A novel sulfonated diamine monomer, 4,4′-bis(4-aminophenoxy)biphenyl-3,3′-disulfonic acid (BAPBDS) with the high basisity and flexible structure was synthesized by direct sulfonation of 4,4′-bis(4-aminophenoxy)biphenyl (BAPB). Sulfonated polyimides (SPIs) were prepared from 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA), BAPBDS and nonsulfonated diamines such as BAPB. The SPI membranes showed much higher water stability at high temperatures than other sulfonated diamine-based SPIs reported so far. Their water vapor sorption isotherm, water uptake (WU), density, dimensional change and proton conductivity σ were investigated. The SPIs showed rather isotropic dimensional changes with WU and the volume increases were slightly smaller than those estimated from the additivity. The SPIs with ion exchange capacities (IECs) of 1.9–2.7 meq/g displayed the similar relationship between σ and WU each other, which was different from those of Nafion 117 and also of the SPIs with the lower IECs. The former SPIs showed reasonably high σ values of 10−2 S/cm or more even at WU of 25 g/100 g dry polymer under 70% RH at 50 °C, whereas the latter showed the similarly high σ values only in liquid water, but not in the nearly saturated water vapor. 相似文献
954.
The nonlinear optical properties of tert-butyl phthalocyanine copper Langmuir-Blodgett (CuttbPc LB) films and vacuum-evaporated phthalocyanine copper (CuPc) films deposited on a metal surface were investigated by second-harmonic generation (SHG) spectroscopy. At the organic/metal interface, a space charge field is formed due to the presence of excess charge injected from a metal electrode to the organic layer. Since the Pc molecule has D4h symmetry, an inversion center is present and the optical SH process is not allowed under the electric-dipole approximation. However, the space charge field at the interface directly influences the symmetric structure of the electrons in the Pc molecule. We investigated the contributions of the surface potential to the SHG using Pc LB and vacuum-evaporated films deposited on aluminum (Al) and gold (Au) metal electrodes, where a distinctive difference in the spectrum for the Pc films on the Al and Au surfaces was observed. The contribution of the surface potential was revealed based on the resonant conditions of the SH process, taking into account the electric-quadrupole transition and dc-field-induced electric-dipole transition. 相似文献
955.
Wagata H Katsumata K Ohashi N Sakai M Nakajima A Fujishima A Okada K Matsushita N 《Photochemistry and photobiology》2011,87(5):1009-1015
Transparent ZnO were prepared using solutions with various trisodium citrate concentrations by a spin-spray method at 90°C. The morphological and structural characteristics, as well as photocatalytic activity of the resulting ZnO films were examined with respect to the added trisodium citrate concentration. Photocatalytic activities of the ZnO films were evaluated from photodecomposition of methylene blue (MB) in aqueous solution. With increasing citrate concentrations, the ZnO films came to have higher transmittances in visible region but lower MB decomposition rate. Both high transmittance and high photocatalytic activity were achieved in the ZnO film prepared in the citrate concentration of 0.5 mm. The possible mechanism for the difference in photocatalytic activity by the samples prepared with the various concentrations of citrate was discussed from the viewpoint of film texture, crystal orientation and surface chemical state. 相似文献
956.
Ken-ichi Nakashima Junko Tomida Tetsuro Kamiya Takao Hirai Yuji Morita Hirokazu Hara Yoshiaki Kawamura Tetsuo Adachi Makoto Inoue 《Tetrahedron letters》2018,59(13):1212-1215
Diaporthols A (1) and B (2), two diphenyl ether derivatives, were isolated from cultures of an endophytic fungus Diaporthe sp. ECN-137 obtained from the leaves of Phellodendron amurense. The structures of 1 and 2 were determined by extensive spectroscopic analyses, and the structure of 2 was confirmed by X-ray crystallographic analysis. Compounds 1 and 2 showed anti-migration activities in TGF-β1-elicited MDA-MB-231 breast cancer cells at a concentration of 20?μM. 相似文献
957.
Ruthenium(II)−Bipyridine/NanoC3N4 Hybrids: Tunable Photochemical Properties by Using Exchangeable Alkali Metal Cations 下载免费PDF全文
Prof. Dr. Kohsuke Mori Daisuke Tatsumi Tomoyuki Iwamoto Prof. Dr. Yoichi Masui Prof. Dr. Makoto Onaka Prof. Dr. Hiromi Yamashita 《化学:亚洲杂志》2018,13(10):1348-1356
A series of nanoporous carbon nitrides that contained a range of alkali metal cations (M@nanoC3N4: M=Li+, Na+, K+, Rb+, and Cs+) have been successfully synthesized from as‐synthesized g‐C3N4 by delamination with concentrated sulfuric acid, followed by neutralization with aqueous solutions of the corresponding alkali metal hydroxides. Tris(2,2′‐bipyridine)ruthenium(II) complexes, [Ru(bpy)3]2+, were grafted onto the carbon nitrides in an effort to explore the physicochemical properties of the deposited [Ru(bpy)3]2+, as well as its photocatalytic activity in the aerobic photooxidation of phenylboronic acid and H2 production from aqueous media in the presence of a Pt co‐catalyst under visible‐light irradiation. Highly porous nanoC3N4 could significantly enhance photocatalytic activity, because of its high surface area, owing to its unique porous structure. More interestingly, the photoluminescence intensities of [Ru(bpy)3]2+ complexes that were associated with M@nanoC3N4 increased in the presence of lighter alkali metal cations, which correlated with increased photocatalytic activities for both reactions. This study demonstrates that M@nanoC3N4 are fascinating supports, in which the local environment of an immobilized metal complex can be precisely controlled by varying the alkali metal cation from Li+ to Cs+. 相似文献
958.
Yoshio Nakahara Yuta Furuno Hitoshi Iwamoto Setsuko Yajima Keiichi Kimura 《Supramolecular chemistry》2018,30(8):697-705
In this study, we report the highly sensitive extraction-fluorometric detection system of Na+ using flow injection analysis with a tetraester derivative of fluorescent calix[4]arene. In liquid-liquid extraction experiments, the fluorescent intensity of calix[4]arene derivative 1 bearing a p-nitrophenol moiety was highly dependent on pH and the Na+ concentration in the aqueous phase. On the other hand, such phenomenon was not observed in the case of calix[4]arene derivative 2, which is almost the same structure as 1 except for a p-nitrophenol moiety. These results show that the proton dissociation of the p-nitrophenol moiety decisively affects the fluorescence intensity of 1. Owing to these fluorescence responsiveness, a calibration graph of the Na+ concentration could be successfully prepared using flow injection analysis with good linearity at the tens of nanomolar level. The tetraester scaffold of calix[4]arene was essential to the detection of Na+ in such a very low concentration range. 相似文献
959.
A method is proposed for the determination of uranium in sea-water. The uranium is strongly sorbed on a strongly basic anion-exchange resin (Cl(-) form) from acidified sea-water containing sodium azide (0.3M) and is easily eluted with 1M hydrochloric acid. Uranium in the effluent can be determined spectrophotometrically with Arsenazo III. The combined method allows easy and selective determination of uranium in sea-water without using a sophisticated adsorbent. The overall recovery and precision are satisfactory at the 3 mug/1. level. 相似文献
960.
Ken-ichi Fujita Shigetoyo FurukawaRyohei Yamaguchi 《Journal of organometallic chemistry》2002,649(2):289-292
The oxidation of primary and secondary alcohols is carried out in acetone under mild conditions using catalytic amounts of [Cp*IrCl2]2 and K2CO3. Primary alcohols are converted into the corresponding aldehydes with high selectivity in good yields. Secondary alcohols are readily oxidized to ketones with smaller amounts of the catalyst. 相似文献