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101.
In the previous work we investigated the influence of depth separation on exclusion of the local effect from the assessment
of the recognized illuminant. Under whitish illumination, only a portion of the local effect was excluded, while this study,
we extended the range of illumination from whitish to chromatic illuminant. We evaluated how the depth separation influences
the amount of local effect under the chromatic illumination. Subjects did perceptual achromatic setting under various combinations
of local surround and illumination conditions. We found that under chromatic illumination, depth separation is more effective
to exclude the local effect even though the local effect was smaller than under whitish chromatic illumination. 相似文献
102.
We describe effective suppression of beam divergence for a high-power laser diode bar by use of an external-cavity technique. Nineteen off-axis external-cavity laser diodes of the high-power laser diode are formed by feedback with a stripe mirror. At three times the threshold current, the diverging angle (1/e2) of the external-cavity laser diode bar is reduced to 1.5 degrees from 6.6 degrees (free running) with 14.1-W peak output power and 70.4% of the radiated power of the free-running state without the external cavity. This technique effectively improves the beam quality of the high-power laser diode bar. 相似文献
103.
Using a hot-isostatic-pressed boron-doped silicon carbide (SiC) material as an example, we demonstrate that the structural width and the chemical width of general boundaries may be quite different. The high-resolution electron microscopy (HREM) observation did not detect the existence of 1 nm thick amorphous film at such grain boundaries (GB). There is only a core structure of 1–2 atomic planes at GB. The chemical width of GB, obtained by the spatially-resolved electron energy-loss spectroscopy (EELS) analysis, is visibly wider than the core region. Furthermore, the spatially-resolved energy-loss near-edge structures (ELNES) analysis not only revealed the chemical bonding between boron and carbon, oxygen and silicon, but also distinguished an extended GB region with chemical bonding modified from that of the grain interiors. Such ELNES analysis defines an ELNES width that is even wider than the chemical width. The three GB widths of different scale construct a comprehensive picture of general boundaries that is remarkably different from general boundaries with amorphous film. Instead of a film confined by the two atomically sharp grain surfaces, there is only one interface, the rough GB core having most of the B–C and Si–O bonds, and the extended grain surface layers, to form such general GB in B-doped SiC. 相似文献
104.
A. Nakajima und K. Shinoda 《Colloid and polymer science》1978,256(4):392
Ohne Zusammenfassung 相似文献
105.
106.
M. Petkovi?S. Stojadinovi? R. Vasili?I. Bel?a Z. Nedi?B. Kasalica U.B. Mio? 《Applied Surface Science》2011,257(22):9555-9561
The growth of silicate tungsten bronzes on aluminum by plasma electrolytic oxidation in 12-tungstosilicic acid is experimentally investigated and discussed. Real time imaging and optical emission spectroscopy characterization of plasma electrolytic oxidation show that spatial density of microdischarges is the highest in the early stage of the process, while the percentage of oxide coating area covered by active discharge sites decreases slowly with time. Emission spectrum of microdischarges has several intensive band peaks originating either from aluminum electrode or from the electrolyte. Surface roughness of obtained oxide coatings increases with prolonged time of plasma electrolytic oxidation, as their microhardness decreases. Raman spectroscopy and energy dispersive X-ray spectroscopy are employed to confirm that the outer layer of oxide coatings formed during the plasma electrolytic oxidation process is silicate tungsten bronzes. 相似文献
107.
Amplitude modulation of laser light is required for resonant sideband extraction employed in gravitational-wave detectors. Amplitude modulation with electro-optic phase modulators is realized by interferometric phase-to-amplitude conversion. Although two outputs modulated at opposite phases to each other are obtained, usually only one of them is utilized and the other is abandoned. The reuse of this abandoned light improves the power efficiency of the modulation. This can be realized by inverting the modulation phase of one output with a delay line and adding it to the other coherently. Moreover, this system selects a high-efficiency operating point and modulates the light in a linear range. We demonstrate that the modulation system can be operated with a power loss that is due only to the losses of the optical components. 相似文献
108.
Organoborane-catatyzed hydroalumination of olefin with dichloroaluminum hydride and subsequent functionalization of the resulting organoaluminum with methyl α-chloro-α-methoxyacetate give rise to the corresponding α-methoxy ester in good yield. 相似文献
109.
Yuki Kitamura Yuki Murata Mizuki Iwai Mio Matsumura Shuji Yasuike 《Molecules (Basel, Switzerland)》2021,26(1)
Pd-catalyzed regioselective C–H arylation is a useful tool for the chemical modification of aromatic heterocycles and 2-arylbenzofuran derivatives are of interest as biologically active substances. Herein, the reaction of triarylantimony difluorides with benzofurans under aerobic conditions in 1,2-DCE, using 5 mol% Pd (OAc)2 and 2 eq. of CuCl2 at 80 °C, produced a variety of 2-arylbenzofurans in moderate-to-high yields. The reaction is sensitive to the electronic nature of the substituents on the benzene ring of the triarylantimony difluorides: an electron-donating group showed higher reactivity than an electron-withdrawing group. Single crystal X-ray analysis of tri(p-methylphenyl) antimony difluoride revealed that the central antimony atom exhibits trigonal bipyramidal geometry. 相似文献
110.
Dr. Masaki Yoshida Dr. Mio Kondo Sena Torii Prof. Ken Sakai Prof. Shigeyuki Masaoka 《Angewandte Chemie (International ed. in English)》2015,54(27):7981-7984
Rational molecular design of catalytic systems capable of smooth O? O bond formation is critical to the development of efficient catalysts for water oxidation. A new ruthenium complex was developed, which bears pendant SO3? groups in the secondary coordination sphere: [Ru(terpy)(bpyms)(OH2)] (terpy=2,2′:6′,2′′‐terpyridine, bpyms=2,2′‐bipyridine‐5,5′‐bis(methanesulfonate)). Water oxidation driven by a Ce4+ oxidant is distinctly accelerated upon introduction of the pendant SO3? groups in comparisons to the parent catalyst, [Ru(terpy)(bpy)(OH2)]2+ (bpy=2,2′‐bipyridine). Spectroscopic, electrochemical, and crystallographic investigations concluded that the pendant SO3? groups promote the formation of an O? O bond via the secondary coordination sphere on the catalyst, whereas the influence of the pendant SO3? groups on the electronic structure of the [Ru(terpy)(bpy)(OH2)]2+ core is negligible. The results of this work indicate that modification of the secondary coordination sphere is a valuable strategy for the design of water oxidation catalysts. 相似文献