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81.
Mizuno H. Matsuzaki N. Osada K. Shinbo T. Ohki N. Ishida H. Ishibashi K. Kure T. 《Solid-State Circuits, IEEE Journal of》1996,31(11):1618-1624
A 1-V 16-KB (L2) 2-KB (L1) four-way set-associative cache was fabricated using a 0.25-μm CMOS technology for future low-power high-speed microprocessors. Effective latency of 6.9 ns and power consumption of 10 mW at 100 MHz are obtained at a supply voltage of 1 V. This performance is achieved by using a new separated bit-line memory hierarchy architecture (SBMHA) that speeds up latency and reduces power consumption, and domino tag comparators (DTC's) that reduce the power dissipation of tag comparisons 相似文献
82.
Kazuhiro Tanaka Yasuharu Osada Hidetoshi Kita Ken-ichi Okamoto 《Journal of Polymer Science.Polymer Physics》1995,33(13):1907-1915
Polyimides with large aromatic rings were prepared from 3,6-diaminocarbazole (CDA), N-ethyl-3,6-diaminocarbazole (ECDA), 2,7-diaminofluorene (DAF), 2,7-diaminofluorenon (DAFO), and dimethyl-3,7-diaminodibenzothiophene-5,5-dioxide (DDBT) with 2-bis(2,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) and 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA). Their physical properties, including gas permeability and permselectivity, were investigated in comparison with those of the related polyimides from 1,3-phenylenediamine (mPD). Glass transition temperatures of the polyimides with large aromatic rings were much higher than those of the mPD-based polyimides as a result of increased rigidity of the former polymer chains. With changing diamine from mPD to the large aromatic diamines, charge transfer (CT) interaction between the moieties of acid anhydride and diamine seems to be enhanced, judging from the red shift of absorption edge of the polyimide films and the red shift of CT excitation band of the 6FDA-based polyimides in solution. Fraction of free space (VF) was a little smaller for the polyimides with large aromatic rings except DDBT than for the mPD-based polyimides, probably because of enhancement in polymer chain-chain interactions as a result of the increased CT interaction. The DDBT-based polyimides had large VF than the mPD-based polyimides because of the nonplanar structure of neighboring dibenzothiophene-5,5-dioxide and imide rings. For the 6FDA-based polyimides, permeability coefficients to H2, O2, N2, CO2, and CH4 were in the order, DAFO < mPD ~ DAF < CDA < ECDA < DDBT. As for the membrane performance for H2/CH4, CO2/CH4, and O2/N2 systems, it is significant to change diamine from mPD to DDBT or CDA, but not to DAF or DAFO. The DDBT-based polyimides were excellent for H2/CH4 and CO2/CH4 separations. © 1995 John Wiley & Sons, Inc. 相似文献
83.
Fumihiko Ozaki Dr. Shunsuke Tanaka YoungHyun Choi Dr. Wataru Osada Kozo Mukai Dr. Mitsuaki Kawamura Dr. Masahiro Fukuda Dr. Masafumi Horio Prof. Dr. Takanori Koitaya Prof. Dr. Susumu Yamamoto Prof. Dr. Iwao Matsuda Prof. Dr. Taisuke Ozaki Prof. Dr. Jun Yoshinobu 《Chemphyschem》2023,24(22):e202300477
Sulfur vacancy on an MoS2 basal plane plays a crucial role in device performance and catalytic activity; thus, an understanding of the electronic states of sulfur vacancies is still an important issue. We investigate the electronic states on an MoS2 basal plane by ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) and density functional theory calculations while heating the system in hydrogen. The AP-XPS results show a decrease in the intensity ratio of S 2p to Mo 3d, indicating that sulfur vacancies are formed. Furthermore, low-energy components are observed in Mo 3d and S 2p spectra. To understand the changes in the electronic states induced by sulfur vacancy formation at the atomic scale, we calculate the core-level binding energies for the model vacancy surfaces. The calculated shifts for Mo 3d and S 2p with the formation of sulfur vacancy are consistent with the experimentally observed binding energy shifts. Mulliken charge analysis indicates that this is caused by an increase in the electronic density associated with the Mo and S atoms around the sulfur vacancy as compared to the pristine surface. The present investigation provides a guideline for sulfur vacancy engineering. 相似文献
84.
A pentafluorophenylammonium triflate (PFPAT) catalyst (5 mol %) successfully promoted C-acylation of enol silyl ethers with acid chloride to produce various beta-diketones (12 examples; 62-92% yield). Similarly, C-acylation of ketene silyl acetals or ketene silyl thioacetals (i.e., crossed Claisen condensation) proceeded smoothly to provide not only alpha-monoalkylated beta-keto (thio)esters but also thermodynamically unfavorable (less accessible) alpha,alpha-dialkylated beta-keto (thio)esters in good to excellent yield (38 examples; 60-92% yield). 相似文献
85.
86.
Tetsuharu Narita Jianping Gong Yoshihito Osada 《Macromolecular rapid communications》1997,18(9):853-857
This paper is a kinetic study of the interaction between an ionic surfactant and an oppositely charged polymer gel. The volume collapse of the gel enhances substantially the velocity of surfactant uptake, despite the decreased free volume for diffusion. This indicates that the increased charge density of the polymer network accelerates the surfactant binding. 相似文献
87.
C. Liang K. Terabe T. Tsuruoka M. Osada T. Hasegawa M. Aono 《Advanced functional materials》2007,17(9):1466-1472
The construction of an electronic‐conductor/ionic‐conductor heterojunction in a well‐defined nanostructure is the basis of studying interfacial and bulk transport and the reactions of ions and electrons at the nanoscale level. An ionic‐conductor/metal (AgI/Ag) heterostructured nanowire array is easily fabricated by a template‐confined, step‐electrochemical technique. The structural and morphological evolution of the AgI/Ag heterostructure before and after its release from the anodic aluminum oxide (AAO) membrane is characterized by scanning electron microscopy, X‐ray diffraction, and optical spectroscopy. The structural disordering of released AgI is suggested by the appearance of a broad photoluminescence emission band at longer wavelengths and a short‐range‐order‐like Raman peak. The ionic conductivity of the AgI nanowire embedded inside the insulating AAO membrane is measured as being on the order of 10–3 S cm–1, which is an enhancement by two to three orders of magnitude compared with that of bulk polycrystalline AgI at room temperature. This electrochemical method could be useful in fabricating other pure and mixed ionic conductors in heterojunction nanostructures. 相似文献
88.
Yoshihito Osada 《Journal of polymer science. Part A, Polymer chemistry》1977,15(2):255-267
A mechanochemical system which works by complexation between a poly(methacrylic acid) (PMAA) network and poly(ethylene glycol) (PEG) was studied. A PMAA membrane swollen with an aqueous PEG solution, to which a load 100 times the weight of the membrane was attached, contracts by over 90% of its length when heated from 10°C to 60°C. The work per contraction was 5 × 10?3 cal/g of membrane. The temperature at which the mechanochemical system undergoes a specified contraction can be regulated by the PEG concentration of the swelling fluid. The sign of the temperature coefficient of the membrane dimension can be reversed by addition of a small amount of ethanol to the swelling solution of PEG. A simple method for calculating the stability constant and thermodynamic parameters for the complexation is outlined. 相似文献
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90.