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41.
The heme acquisition system A protein secreted by Pseudomonas aeruginosa (HasAp) can capture several synthetic metal complexes other than heme. The crystal structures of HasAp harboring synthetic metal complexes revealed only small perturbation of the overall HasAp structure. An inhibitory effect upon heme acquisition by HasAp bearing synthetic metal complexes was examined by monitoring the growth of Pseudomonas aeruginosa PAO1. HasAp bound to iron–phthalocyanine inhibits heme acquisition in the presence of heme‐bound HasAp as an iron source.  相似文献   
42.
A wavelength filter with simple structure using multimode waveguide is proposed . The device uses mode conversion by a grating structure fabricated simultaneously with the multimode waveguide.  相似文献   
43.
 Poly(ethylene oxide) macromonomers carrying methoxy group on the one (α-) end and methacryloyloxyhexyl or methacryloyloxydecyl group on the other (ω-) end were prepared, homopolymerized in water, and dispersion-copolymer-ized with styrene or methyl methacrylate in a methanol–water mixture. They were found to polymerize more rapidly and to produce stable polystyrene dispersions more effectively, as compared to the corresponding macromonomers carrying either α-methoxy and or α-dodecyloxy and ω-methacryloyloxy end groups. Thus, the amphiphilic constitution of the macromonomers such that favors the polymerizing methacrylate end groups to locally concentrate into the micelle core or to the particle surface while the poly(ethylene oxide) chains extending to the medium appears to be most important in enhancing their polymerizability and effectiveness as reactive steric stabilizers. On the other hand, stable poly(methyl methacry-late) particles with a number of craters or pleats on the surface were produced with a PEO macromono-mer with α-methoxy and ω-methacryl-oyloxy end groups. Received: 4 September 1996 Accepted: 18 October 1996  相似文献   
44.
Semicrystalline network polymers were obtained by the Diels–Alder (DA) reaction of furyl‐telechelic poly(ε‐caprolactone) and tris(2‐maleimide ethyl)amine. Controlling the rates of crystallization and crosslinking reaction gave materials with various properties. Curing at a temperature much below Tm of poly(ε‐caprolactone), at which crystallization proceeded first followed by DA reaction, gave a hard and stiff material, whereas curing above Tm gave a soft and stretchable one. When crystallization and crosslinking were promoted simultaneously, tough and ductile materials were obtained. Structural analysis of the network polymers showed that the variation in the properties was derived from the difference in the crystallinity, crystallite size, and network structure. Therefore, materials with various mechanical properties, from soft to hard, could be obtained by simple thermal treatment. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   
45.
Morphological changes of solution‐grown poly[(R)‐3‐hydroxybutyrate] lamellar crystals during heating were directly investigated by atomic force microscopy. The thickening of lamellar crystals was further visualized by enzymatic degradation of less‐ordered crystal regions in thermally treated lamellar crystals. The morphological changes of lamellar crystals induced by thermal treatment are due to recrystallization.  相似文献   
46.
Effects of a pan-ROCK-inhibitor, ripasudil (Rip), and a ROCK2 inhibitor, KD025 on dexamethasone (DEX)-treated human trabecular meshwork (HTM) cells as a model of steroid-induced glaucoma were investigated. In the presence of Rip or KD025, DEX-treated HTM cells were subjected to permeability analysis of 2D monolayer by transendothelial electrical resistance (TEER) and FITC–dextran permeability, physical properties, size and stiffness analysis (3D), and qPCR of extracellular matrix (ECM), and their modulators. DEX resulted in a significant increase in the permeability, as well as a large and stiff 3D spheroid, and those effects were inhibited by Rip. In contrast, KD025 exerted opposite effects on the physical properties (down-sizing and softening). Furthermore, DEX induced several changes of gene expressions of ECM and their modulators were also modulated differently by Rip and KD025. The present findings indicate that Rip and KD025 induced opposite effects toward 2D and 3D cell cultures of DEX-treated HTM cells.  相似文献   
47.
48.
Through bioassay-guided isolation, five compounds with growth inhibitory activity on S1T, an adult T-cell leukemia (ATL) cell line, were isolated from the crude methanol extract of the aerial parts of Hyptis verticillata.  相似文献   
49.
This paper presents multispectral image coding methods based on visible component separation techniques. By coding the visible components separately from other spectral components, the color information can be used without decoding the whole multispectral image. Two types of separation techniques are introduced: one is a direct separation of visible and invisible layers, while the other is a scalable separation. In the scalable separation, visible components are first compressed to produce the base layer bitstream. The enhancement layer data include not only invisible components but also the information on the distortion of the coded visible components. Such a separation technique improves the accuracy of decoded multispectral images especially when visible components are highly compressed. The performance of the proposed methods was evaluated for different bit allocations to visible components. In general, the coding performance reduces when data are divided and coded separately to incorporate scalabilities. Nonetheless, it is found that the proposed scalable approach realizes a peak signal-to-noise ratio PSNR value comparable to that achieved by employing JPEG2000, which incorporates no scalability.  相似文献   
50.
The molecular orientations and dynamics of 2,2,6,6‐tetramethyl‐1‐piperidinyloxyl (TEMPO) radical derivatives with large substituent groups at the 4‐position (4‐X‐TEMPO) in the organic one‐dimensional nanochannels within the nanosized molecular template 2,4,6‐tris(4‐chlorophenoxy)‐1,3,5‐triazine (CLPOT) were examined using ESR. The concentrations of guest radicals, including 4‐methoxy‐TEMPO (MeO‐TEMPO) or 4‐oxo‐TEMPO (TEMPONE), in the CLPOT nanochannels in each inclusion compound (IC) were reduced by co‐including 4‐substituted‐2,2,6,6‐tetramethylpiperidine (4‐R‐TEMP) compounds at a ratio of 1 : 30–1 : 600. At higher temperatures, the guest radicals in each IC underwent anisotropic rotational diffusion in the CLPOT nanochannels. The rotational diffusion activation energy, Ea, associated with MeO‐TEMPO or TEMPONE in the CLPOT nanochannels (6–7 kJ mol?1), was independent of the size and type of substituent group and was similar to the Ea values obtained for TEMPO and 4‐ hydroxy‐TEMPO (TEMPOL) in our previous study. However, in the case in which TEMP was used as a guest compound for dilution (spacer), the tilt of the rotational axis to the principal axis system of the g ‐tensor, and the rotational diffusion correlation time, τR, of each guest radical in the CLPOT nanochannels were different from the case with other 4‐R‐TEMP. These results indicate the possibility of controlling molecular orientation and dynamics of guest radicals in CLPOT ICs through the appropriate choice of spacer. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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