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991.
Takashi Doi Tsutomu Shimokawa Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2019,57(4):531-538
This article presents the effect of some ionic photochemical acid generators (PAGs) to inhibit the dissolution of hexafluoroisopropylalcohol (HFA)‐containing polystyrene to an aqueous alkaline developer, which is a highly important effect in photoresist application to enhance resolution of patterning. The dissolution inhibiting factors and mechanisms were investigated by evaluating the solubility and the 1H‐NMR analysis of OH proton in HFA moiety. The dissolution inhibition effect was enhanced when the structures of PAGs fulfill some requirements: (a) their anions should have higher basicity and smaller van der Waals volume; (b) their cations should be stabilized by conjugation with electron‐rich aromatics. In the dissolution inhibition, the HFA moiety interacts with the anionic part of PAGs liberated from the electrostatic interaction with the counter cation. These interactions were predicted and quantified by DFT calculations using Gaussian 09, leading to the rational designs of PAGs with higher dissolution inhibiting effect in photoresist systems. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 531–538 相似文献
992.
Shota Yamada Dr. Takeshi Matsumoto Prof. Dr. Ho-Chol Chang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(35):8268-8278
The oxidation of [MII(3,5-DTBCat)(DTBbpy)] (M=Ni ( [Ni] ), Pd ( [Pd] ), and Pt ( [Pt] ); 3,5-DTBCat=3,5-di-tert-butylcatecholato; DTBbpy=4,4′-di-tert-butyl-2,2′-bipyridine) afforded the dimeric {[NiII(3,5-DTBSQ)(DTBbpy)](PF6)}2 ( {[Ni](PF6)}2 ; 3,5-DTBSQ=3,5-di-tert-butylsemiquinonato) and monomeric semiquinonato (SQ) complexes [MII(3,5-DTBSQ)(DTBbpy)](PF6) (M=Pd ( [Pd](PF6) ) and Pt ( [Pt](PF6) )). The negative solvatochromic properties of the SQ complexes allowed us to estimate the relative order of their dipole moments: [Pd](PF6) > [Pt](PF6) > {[Ni](PF6)}2 . The complexes [Pd](PF6) and [Pt](PF6) adopt monomeric structures and are stable in CH2Cl2 and toluene, whereas they gradually disproportionate at room temperature to [M] and 3,5-di-tert-butylbenzoquinone (3,5-DTBBQ) in polar solvents such as THF, MeOH, EtOH, DMF, or DMSO. The results of spectroscopic studies suggested that the oxidized nickel complex adopts a monomeric structure ( [Ni](PF6) ) in CH2Cl2, but a dimeric structure ( {[Ni](PF6)}2 ) in the other investigated solvents. In polar solvents, {[Ni](PF6)}2 may disproportionate to [Ni] and 3,5-DTBBQ at 323 K, thereby demonstrating a significant solvent- and metal-dependence in temperature. The relative activities of {[Ni](PF6)}2 and [M](PF6) toward disproportionation are related to the electrochemically estimated Kdis values in CH2Cl2 and DMF. The present work demonstrates that solvent polarity and the dipole moments of the SQ complexes promote disproportionation, which can be controlled by a judicious choice of the metal ion, solvent, and temperature. 相似文献
993.
Kenta Sato Dr. Masashi Hasegawa Yuki Nojima Nobuyuki Hara Dr. Tomohiko Nishiuchi Prof. Dr. Yoshitane Imai Prof. Dr. Yasuhiro Mazaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(4):1323-1329
A curved stereogenic [6]paraphenylene ([6]PP), anchoring a chiral binaphthyl scaffold at 7,7’-positions, was prepared and investigated for its properties as a solid-state circularly polarized luminescence (CPL) dye. X-ray analysis revealed a helically twisted structure of PP units induced by axial chirality of binaphthyl framework. The curved [6]PP exhibits fluorescence in powder and polymethyl methacrylate (PMMA) film as well as solution. A significant increase in quantum yield was observed for a non-fluid PMMA film owing the suppression of the molecular motion. The gCPL values of the dye in solution and as PMMA film were almost the same (4.3–4.4×10−3) and lager than that in powder. TD-DFT calculations in the excited state suggest that the exciton can be delocalized into a twisted PP unit to produce a larger magnetic transition dipole moment. 相似文献
994.
Chihiro Suzuki Izumi Murakami Fumihiro Koike Takeshi Higashiguchi Hiroyuki A. Sakaue Naoki Tamura Shigeru Sudo Gerry O'Sullivan 《X射线光谱测定》2020,49(1):78-84
We are developing an experimental database of extreme ultraviolet spectra from highly charged ions using optically thin high-temperature plasmas produced in the Large Helical Device. Spectra from a variety of elements with atomic numbers ranging from 36 to 83 have been systematically recorded in the range of 1–20 nm by a grazing incidence spectrometer. For higher Z elements from tin onward, discrete or quasicontinuum spectral features from n=4 (N-shell) ions are mainly observed depending upon the plasma temperature, which leads to some new experimental identifications of spectral lines. On the other hand, major emitters are n=3 (M-shell) ions for medium Z elements from krypton to ruthenium. The calculated wavelengths for Δn≠0 transitions agree well with the measurements and the calculated wavelengths are systematically shifted to shorter wavelengths for Δn=0 transitions associated with inner-subshell excited configurations. 相似文献
995.
Keigo Matsuyama Akito Fukui Kohei Miura Hisashi Ichimiya Yuki Aoki Yuki Yamada Prof. Atsushi Ashida Prof. Takeshi Yoshimura Prof. Norifumi Fujimura Prof. Daisuke Kiriya 《ChemistryOpen》2019,8(7):908-914
Transition metal dichalcogenides (TMDCs) have received attention as atomically thin post-silicon semiconducting materials. Tuning the carrier concentrations of the TMDCs is important, but their thin structure requires a non-destructive modulation method. Recently, a surface-charge transfer doping method was developed based on contacting molecules on TMDCs, and the method succeeded in achieving a large modulation of the electronic structures. The successful dopant is a neutral benzyl viologen (BV0); however, the problem remains of how to effectively prepare the BV0 molecules. A reduction process with NaBH4 in water has been proposed as a preparation method, but the NaBH4 simultaneously reacts vigorously with the water. Here, a simple method is developed, in which the reaction vial is placed on a hotplate and a fragment of air-stable metal is used instead of NaBH4 to prepare the BV0 dopant molecules. The prepared BV0 molecules show a strong doping ability in terms of achieving a degenerate situation of a TMDC, MoS2. A key finding in this preparation method is that a convection flow in the vial effectively transports the produced BV0 to a collection solvent. This method is simple and safe and facilitates the tuning of the optoelectronic properties of nanomaterials by the easily-handled dopant molecules. 相似文献
996.
Suguru Motokucho Atsushi Sudo Fumio Sanda Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2004,42(10):2506-2511
A novel branched polycarbonate with a hydroxyl group at the chain end was synthesized by the copolymerization of glycidol with carbon dioxide (CO2). The copolymerization was carried out with 5 mol % of an alkali metal halide or quaternary ammonium salt as a catalyst under atmospheric CO2. The obtained poly(glycidol‐co‐carbon dioxide) was O‐benzoylated and O‐silylated, and the corresponding polymers were analyzed with IR, size exclusion chromatography, 13C NMR, and 29Si NMR. The IR spectroscopy analysis of the O‐benzoylated polymer revealed that the maximum incorporation degree of the carbonate group was 90% (i.e., the CO2/glycidol composition ratio was 0.9:1.0). The incorporation of CO2 as a carbonate unit was also confirmed by the treatment of this polymer with n‐butylamine, which caused the aminolysis of the carbonate and led to degraded products. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2506–2511, 2004 相似文献
997.
998.
Kentarou Suzuki Hisakazu Horii Yuko Sugita Fumio Sanda Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2004,42(17):4276-4283
It was demonstrated that the reaction of epoxide and imine as a latent initiator under highly humid conditions was accelerated by addition of 5‐phenoxymethyl‐1,3‐oxathiolane‐2‐thione ( 1 ). When 1 was added to a mixture of glycidyl phenyl ether and an imine, the reaction of the epoxide with an amine released from the imine became faster than was the case without 1 , that is, 1 worked as a promoter of the reaction. The curing rate and initial adhesive strength of epoxy resin increased compared with that without 1 . © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4276–4283, 2004 相似文献
999.
Junji Nakano Moon Yul Huh Yoshikazu Yamamoto Takeshi Fujiwara Ikunori Kobayashi 《Computational Statistics》2004,19(1):137-146
Summary Jasp is an experimental general purpose Java-based statistical system which adopts several new computing technologies. It
has a function-based and object-oriented language, an advanced user interface, flexible extensibility and a server/client
architecture with distributed computing abilities. DAVIS is, on the other hand, a stand-alone Java-based system, and is designed
for providing advanced data visualization functions with easy operations by a GUI. In this paper, it is made possible to use
tools of DAVIS from within Jasp, in order that the new integrated system can handle not only data filtering and statistical
analysis but also data visualization. We develop a mechanism for extending the server/client system of Jasp to realize an
efficient collaboration with DAVIS in the client-side. It is shown that the mechanism is straightforward and simple. 相似文献
1000.
Yuichi Takaku Takuma Hayashi Ikuko Ota Hidenao Hasegawa Shinji Ueda 《Analytical sciences》2004,20(7):1025-1028
An analytical method for trace levels of iron in a seawater sample using isotope dilution ICP-MS was developed. Preconcentration of iron and the removal of major elements in seawater such as alkali and alkaline-earth elements can be carried out quickly using a chelating resin disk by adjusting the sample pH to 3. The collision cell option of the ICP-MS instrument method was used to improve the performance of the instrument for iron measurements since ArO and ArN interferences could be reduced using this analytical method. About 4 ml min(-1) helium, as the collision gas, were introduced into the cell. 40Ar14N and 40Ar16O which interfere with 54Fe and 56Fe in water had their amounts decreased by 5 orders of magnitude. Then, the isotope dilution method was used for iron determination below ng g(-1) level of trace iron in four environmental reference materials (river water standard sample JAC-0031 (Japan Soc. for Analytical Chemistry), estuarine standard sample SLEW-2 (NRC Canada) and seawater standard samples CASS-3 and NASS-5 (NRC Canada)) were measured. Good agreement between analytical results and certified values of reference materials was obtained, which confirmed the effectiveness of this method. 相似文献