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991.
The supercritical-pressure water-cooled fast reactor (SWFR) is a fast spectrum supercritical water-cooled reactor (SCWR) studied by the University of Tokyo. The SWFR is designed as a two-pass core with an outlet temperature 500 °C. The SWFR has fuel channels cooled by downward flow, higher power density, and smaller coolant density reactivity feedback compared with Super LWR. This paper describes the safety analyses of abnormal events for the SWFR. SPRAT-F code is used for the safety analysis at supercritical pressure considering the downward flow cooled seed fuel channel. This code is based on a 1-D node junction model with point kinetics and decay heat calculations. Flow redistribution among parallel paths is calculated by pressure-loss balance and momentum conservation. The initiating events are selected from those of LWRs. For the safety analysis, nine abnormal transients and four accidents are selected with considering types of abnormality. By the numerical analyses, it was found that the loss of flow events can be mitigated by the “water source” effect of the downward flow blanket channels in the abnormal transients and accidents. All the abnormal events satisfy the criteria with margin. 相似文献
992.
Takaaki Tsurumi Motohiro Shono Hirofumi Kakemoto Satoshi Wada Kenji Saito Hirokazu Chazono 《Journal of Electroceramics》2008,21(1-4):17-21
Capacitance aging under DC electric fields has been studied on multilayer ceramic capacitors (MLCCs) with the X7R characteristics. The capacitance change with time was divided into two stages, the first- and the second-stage. The first-stage was due to the nonlinear permittivity of dielectrics and it should not be involved in the aging phenomenon. The second-stage depended on the MnO content, grain size and firing condition of dielectrics. From the behavior of the second-stage, it was concluded that the capacitance aging was caused by the 90-degree domain switching in BaTiO3 in the core. The first-stage was due to the nonlinear permittivity but the domain switching was also included in the first-stage if the domain walls moved by the first application of DC field. The change in the aging behavior with the intensity of DC field could be explained by separating capacitance change into the nonlinear permittivity and the domain switching according to the mechanism proposed in this study. 相似文献
993.
Okamura A Hagiwara T Yamagami S Yamaguchi M Shinbo T Kanamori T Kondo S Miwa K Itagaki I 《Journal of Bioscience and Bioengineering》2008,105(3):221-225
We previously developed a cell separation method using a poly(N-isopropylacrylamide)-grafted polypropylene (PNIPAAm-g-PP) membrane containing an adsorbed monoclonal antibody (mAb). The purpose of this study is to elucidate the cell separation mechanism in detail and to design an optimal method. As the grafting yield of PNIPAAm increased, the level of the adsorption of IgG(1) and cell adhesion to the membrane decreased. After BSA was adsorbed to a PNIPAAm-g-PP membrane at 6 degrees C, where PNIPAAm was hydrophilic, a small amount of IgG(1) was adsorbed to the membrane at 37 degrees C, where PNIPAAm was hydrophobic. The desorption of the adsorbed IgG(1) was not enhanced even though temperature was reduced to 10 degrees C, where PNIPAAm was hydrophilic. These results indicate that the antibody adsorbed to the intact PP surface of the membrane predominantly contributes to the capture of target cells through the antigen-antibody reaction and that a thermoresponsive transition of PNIPAAm contributes to the detachment of the captured cells. The total number of cells recovered from a PNIPAAm-g-PP membrane containing the adsorbed mAb decreased as the grafting yield increased. A PNIPAAm-g-PP membrane with a 1.7% grafting yield containing adsorbed anti-human CD34 mAb enriched CD34-positive KG-1a cells to 85% from a 1:1 cell suspension of KG-1a cells and CD34-negative Jurkat cells. 相似文献
994.
Multi-walled carbon nanotube networks were confirmed to exhibit a linear decrease in resistivity with increasing temperature from 100 to above 400 K.The linearity was explained using a defect scattering model that involved Friedel oscillations(that is,electron-electron interactions).The applicability of this model,which was originally proposed for graphene,to carbon nanotubes was assessed based on a comparison of various experimental data.Increases in the slopes of the resistivity-temperature plots following the introduction of defects,as well as an effect of charge concentration on the slope were key predictions of this model.The results obtained from few-walled carbon nanotube networks are also shown.In the literature,linear resistivity-temperature plots were obtained from other graphene derivatives,indicating that the linearity originates from the hexagonal symmetry of these materials.The present work also indicated a relationship between the appearance of linearity and negative magnetoresistance above 100 K.Based on a mechanism incorporating scattering in association with Friedel oscillations and conventional electron conduction models,the universality of resistivity-temperature plots obtained from carbon nanotube networks is introduced. 相似文献
995.
Yoshiro Tahara Satoshi Kosuge Shin-ichi Sawada Yoshihiro Sasaki Kazunari Akiyoshi 《Reactive and Functional Polymers》2013,73(7):958-964
Polysaccharide nanogels are one of the most attractive carriers for drug delivery systems. Nanogels encapsulate proteins in their hydrated polymer networks, and minimize the denaturation of proteins. In this study, we demonstrated the cross-linking of acryloyl group-modified polysaccharide nanogels via photopolymerization, which allowed the formation of novel hydrogel particles and macrogels. The mechanical properties of the resultant hydrogels depended on the concentrations of the nanogels and the cross-linkers. The most significant property of the nanogel-cross-linked hydrogel was the ability to encapsulate insulin via hydrophobic interactions. After incubation of the hydrogel containing insulin in water, the hydrogel was degraded by hydrolysis, and insulin was gradually released from the hydrogels over a period of 1 week. According to these results, this nanogel-cross-linked hydrogel prepared via photopolymerization has potential for innovative biomaterials. 相似文献
996.
Masato Ohsawa Kouichi Tamura Tomohiko Kanaoka Hiromichi Wakui Akinobu Maeda Toru Dejima Kengo Azushima Kazushi Uneda Ryu Kobayashi Yuko Tsurumi-Ikeya Yoshiyuki Toya Tetsuya Fujikawa Satoshi Umemura 《International journal of molecular sciences》2013,14(8):15361-15375
An altered ambulatory blood pressure (BP) and heart rate (HR) profile is related to chronic kidney disease (CKD) and cardiorenal syndrome. In this study, we examined the effects of aliskiren, when added to angiotensin II type 1 receptor blockers, on ambulatory BP and cardiorenal function in CKD. Thirty-six hypertensive CKD patients were randomly assigned to the aliskiren add-on group (n = 18) or the benazepril add-on group (n = 18). Ambulatory BP and cardiorenal function parameters were measured at baseline and 24 weeks after treatment. Compared with the benazepril group, nighttime systolic BP variability in the aliskiren group was lower after treatment. Albuminuria was decreased in the aliskiren group, but not in the benazepril group. In addition, left ventricular mass index (LVMI) was significantly lower in the aliskiren group than in the benazepril group after treatment. In the aliskiren group, multivariate linear regression analysis showed an association between changes in albuminuria and changes in nighttime systolic BP. Furthermore, there were associations between changes in LVMI and changes in daytime HR variability, as well as between changes in LVMI and changes in plasma aldosterone concentration. These results suggest that aliskiren add-on therapy may be beneficial for suppression of renal deterioration and pathological cardiac remodeling through an improvement that is effected in ambulatory BP and HR profiles. 相似文献
997.
Yusuke Kashihara Shun Okada Yoshiaki Urahama Shigeki Hikasa Satoshi Makuta Kazuko Fujiwara Syuji Fujii Yoshinobu Nakamura 《应用聚合物科学杂志》2019,136(13):47272
The effects of the tensile test rate on the properties of a pressure-sensitive adhesive (PSA) and of vulcanized rubber were ascertained and compared, using a poly(n-butyl acrylate-acrylic acid) random copolymer with varying degrees of crosslinking as the PSA. The 100% modulus of the PSA was found to increase along with the crosslinking degree and with faster tensile test rates. In contrast, the 100% modulus of the vulcanized rubber did not exhibit any test rate dependence. To assess this effect, the molecular weights between chemical and physical crosslinking points were determined via equilibrium swelling, dynamic mechanical analysis, and tensile tests. The proportion of physical crosslinking points was found to be far larger in the crosslinked PSA. Because these entanglement points can readily disentangle in response to slow deformation, variations in the test rate only affected the PSA. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47272. 相似文献
998.
Polymer prepared from a monomer ((S)‐configuration at stereogenic center) in a cholesteric liquid crystal (CLC) medium consisting of chiral molecules in (R)‐configuration, a three‐dimensional (3D) chiral continuum, exhibits intense Cotton effect compared to polymer prepared in the CLC with (S)‐configuration. This result can be explained by intermolecular interaction between the monomer and the CLC medium in the polymerization process. The intramolecular twisted structure along the polymer chain (secondary structure) and the helical aggregation between the polymer chains (intermolecular structure and tertiary structure) induced by the liquid crystal medium as 3D chiral continuum are discussed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
999.
Takahisa Ikeue Makoto Sonoda Satoshi Kurahashi Haruaki Tachibana Daichi Teraoka Tamotsu Sugimori Kuninobu Kasuga Makoto Handa 《Inorganic chemistry communications》2010,13(10):1170-1172
An annulated dinuclear palladium(II) phthalocyanine complex (1) was synthesized and characterized. It was found that 1 worked as a photo-catalyst for the decomposition of 1,3-diphenylisobenzofuran (DPBF) in aerated toluene under the irradiation of the light in the near-infrared (NIR) region (λ > 780 nm). 相似文献
1000.
In this study, various Cu-based spinel compounds, i.e., CuFe2O4, CuMn2O4, CuAl2O4 and CuLa2O4, were fabricated by a solid-state reaction method. Reduction behaviors and morphological changes of these materials have been characterized by H2 temperature-programmed reduction (H2-TPR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Moreover, the catalytic properties for steam reforming of methanol (SRM) of these Cu-based spinel compounds were investigated. H2-TPR results indicated that the reducibility of Cu-based spinel compounds was strongly dependent on the B-site component while the CuFe2O4 catalyst revealed the lowest reduction temperature (190 °C), followed respectively by CuAl2O4 (267 °C), CuMn2O4 (270 °C), and CuLa2O4 (326 °C). The reduced CuAl2O4 catalyst demonstrated the best performance in terms of catalytic activity. Based on the SEM and XRD results, pulverization of the CuAl2O4 particles due to gas evolution and a high concentration of nanosized Cu particles (≈50.9 nm) precipitated on the surfaces of the Al2O3 support were observed after reduction at 360 °C in H2. The BET surface area of the CuAl2O4 catalyst escalated from 5.5 to 13.2 m2/g. Reduction of Cu-based spinel ferrites appear to be a potential synthesis route for preparing a catalyst with high catalytic activity and thermal stability. The catalytic performance of these copper-oxide composites was superior to those of conventional copper catalysts. 相似文献