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991.
At present there is significant interest in the doping of various types of dyes into polymer dispersed liquid crystals (PDLCs) in display films. Till to date, various types of dyes have been employed to improve the electro-optical properties of PDLC films in various situations by different research groups. Some of the advantageous features of dye-doped PDLC predict that such dye-doping into the PDLC films resolve the scattering effect, improve the films absorbance, enhance the degree of alignment, stability, and the electro-optical properties of the film such as reflectance, contrast ratio and better transmittance. The current article contains a short review on the present and past studies conducted on the dye-doped polymers dispersed liquid crystals films. The fabrication techniques and their various applications in the different display areas are reviewed, along with the new key findings are discussed. 相似文献
992.
While the indentation method is an excellent way to evaluate the mechanical properties of various sizes of materials, from the nano-scale to the macro-scale, its applications have been limited to measuring mechanical properties. In this study we propose a new application of the dynamic indentation method, in an indentation machining technology for mass-production. The core idea is that the array of residual indentations generated by dynamic indentation testing can be used to fabricate a lens array suitable for thinner and brighter displays. We developed an advanced system from a dynamic indentation system, whose maximum speed and maximum specimen size were about 10Hz and 250 mm*250 mm, respectively. Using dual actuating heads this system was used to produce arrays of lenses having depths of 1 μm to 6 mm. Pile-up is a critical reason why indentation machining technology had been not widely used in display industries. Since lower pile-up is observed in more ductile copper-based metals, we increased the annealing time of the metal molds to reduce the amount of pile-up. Then, following a quantitative analysis of the annealing heat treatment and resulting amount of pile-up, a lens array was successfully machined on a metal mold fabricated by the developed system. The machined metal mold was used to manufacture optical plates for a lens array. The results verified that the indentation machining technology proposed in this study, based on the dynamic indentation method, can be applied for the manufacturing of optical components for better displays. 相似文献
993.
An efficient synthesis of valienamine is described. Valienamine was synthesized starting from commercially available 2,3,4,6-tetra-O-benzyl-D-glucose in nine steps, using ring-closing metathesis of (4S,5S,6S)-4,5,6-tribenzyloxy-7-(benzyloxymethyl)octa-1,7-dien-3-ol as a key step. 相似文献
994.
Novel molecular drug carrier: encapsulation of oxaliplatin in cucurbit[7]uril and its effects on stability and reactivity of the drug 总被引:1,自引:0,他引:1
Jeon YJ Kim SY Ko YH Sakamoto S Yamaguchi K Kim K 《Organic & biomolecular chemistry》2005,3(11):2122-2125
Oxaliplatin forms a stable 1:1 inclusion complex with cucurbit[7]uril as indicated by NMR, mass spectrometry, isothermal titration calorimetry and X-ray crystallography. The encapsulation of the drug results in a large enhancement in stability, a moderate decrease in reactivity toward guanosine but a much larger decrease in reactivity toward L-methionine, which suggests the encapsulation not only increases the stability of the drug but also may reduce unwanted side effects caused by protein binding of the platinum drug. A preliminary in vitro assay using various tumor cell lines reveals that the encapsulation results in a decrease in the antitumor activity of oxaliplatin. 相似文献
995.
We produced, for the first time, monodisperse NiH(x) nanoparticles with particle diameters of 7.0 nm and investigated their magnetic properties. We also produced monodisperse Ni nanoparticles with nearly the same particle diameters as those of NiH(x) nanoparticles as a comparison. The magnetic properties of NiH(x) nanoparticles were quite different from those of Ni nanoparticles. We observed two compositional phases in NiH(x) nanoparticles, similar to bulk material: one is the nearly pure Ni phase with the blocking temperature (T(B)) of 11 K and the other is the hydride phase. We observed T(B) of 40 K in Ni nanoparticles. 相似文献
996.
A preceramic polymer for boron carbonitride was synthesized for the first time by the hydroboration of borazine derivatives, B-triethynyl, N-trimethyl borazine and borazine, without a catalyst. A homogeneous, amorphous boron carbonitride ceramic was prepared by the thermolysis of a hydroborated copolymer in an argon atmosphere. 相似文献
997.
Propargylic and activated allylic amines are known to inactivate the quinone-dependent plasma amine oxidases, possibly through active-site modification by the alpha,beta-unsaturated aldehyde turnover products. Although homopropargylamine (1-amino-3-butyne, 1) is a nonobvious candidate as a mechanism-based inhibitor, 1 was found to be an unusually potent time- and concentration-dependent irreversible inactivator of bovine plasma amine oxidase (BPAO), exhibiting a 30 min IC(50) of 2.9 microM at 30 degrees C ([BPAO] = 1.2 microM). Preserved cofactor redox activity of the denatured inactivated enzyme indicates that inactivation by 1 involves either a cofactor modification that reverses upon enzyme denaturation or a modification of an active-site residue. Because inactivation by 1 may involve enzyme alkylation by the reactive 2,3-butadienal (3) tautomer of the 3-butynal turnover product of 1, aldehyde 3 was prepared and was found to inactivate BPAO, but only at high concentration. In addition, whereas inhibition by 3 was blunted by the presence of mercaptoethanol, no such protection was observed against 1. The amine whose turnover should lead directly to 3 was prepared (1-amino-2,3-butadiene, 4) and was found to be an even more potent inactivator of BPAO than 1, exhibiting a 5 min IC(50) of 1.25 microM. Rat liver mitochondrial monoamine oxidase was also inactivated by 4, as expected, but only very weakly by 1. Potential mechanisms explaining the selective inhibition of BPAO by 1 are discussed. 相似文献
998.
When two-dimensional electrons are subjected to a very strong magnetic field, they are believed to form a triangular crystal. By a direct comparison with the exact wave function, we demonstrate that this crystal is not a simple Hartree-Fock crystal of electrons but an inherently quantum mechanical crystal characterized by a nonperturbative binding of quantized vortices to electrons. It is suggested that this has qualitative consequences for experiment. 相似文献
999.
Rhee HS Oh SH Ko BJ Han DM Jeon BH Park H Moon HB Kim WS 《Experimental & molecular medicine》2003,35(3):160-166
The enzyme complex 3beta-hydroxysteroid dehydrogenase/Delta5-Delta4-isomerase (3beta-HSD) is involved in the biosynthesis of all classes of active steroids. The expression of 3b-HSD in human uterine endometrium during the menstrual cycle and decidua was examined in an effort to understand its role during ova implantation. 3beta-HSD was weakly expressed in the glandular epithelium of the proliferative phase and moderately expressed in the glandular epithelium of secretory phase of the endometrium. In the decidua of the ectopic pregnancy, 3beta-HSD was strongly expressed. The human uterine endometrial 3beta-HSD was identified as being the same type as the placental 3beta-HSD by RT-PCR and sequence analysis. In addition to the expression of 3beta-HSD, P450scc was expressed in the decidua of the ectopic pregnancy. These results suggest that pregnenolone might be synthesized from cholesterol by P450scc de novo and then, it is converted to progesterone by 3beta-HSD in the uterine endometrium. The data implies that the endometrial 3beta-HSD can use not only the out-coming pregnenolone from the adrenal gland but also the self- made pregnenolone to produce progesterone. The de novo synthesis of progesterone in the endometrium might be a crucial factor for implantation and maintenance of pregnancy. 相似文献
1000.
Jeon Y. Sloan I.H. Stephan E.P. Elschner J. 《Advances in Computational Mathematics》1997,7(4):547-571
We consider a fully discrete qualocation method for Symm’s integral equation. The method is that of Sloan and Burn (1992),
for which a complete analysis is available in the case of smooth curves. The convergence for smooth curves can be improved
by a subtraction of singularity (Jeon and Kimn, 1996). In this paper we extend these results for smooth boundaries to polygonal
boundaries. The analysis uses a mesh grading transformation method for Symm’s integral equation, as in Elschner and Graham
(1995) and Elschner and Stephan (1996), to overcome the singular behavior of solutions at corners.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献