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111.
We evaluated the abscopal effect of re-implantation of liquid nitrogen-treated tumor-bearing bone grafts and the synergistic effect of anti-PD-1 (programmed death-1) therapy using a bone metastasis model, created by injecting MMT-060562 cells into the bilateral tibiae of 6–8-week-old female C3H mice. After 2 weeks, the lateral tumors were treated by excision, cryotreatment using liquid nitrogen, excision with anti-PD-1 treatment, and cryotreatment with anti-PD-1 treatment. Anti-mouse PD-1 4H2 was injected on days 1, 6, 12, and 18 post-treatment. The mice were euthanized after 3 weeks; the abscopal effect was evaluated by focusing on growth inhibition of the abscopal tumor. The re-implantation of frozen autografts significantly inhibited the growth of the remaining abscopal tumors. However, a more potent abscopal effect was observed in the anti-PD-1 antibody group. The number of CD8+ T cells infiltrating the abscopal tumor and tumor-specific interferon-γ (IFN-γ)-producing spleen cells increased in the liquid nitrogen-treated group compared with those in the excision group, with no significant difference. The number was significantly higher in the anti-PD-1 antibody-treated group than in the non-treated group. Overall, re-implantation of tumor-bearing frozen autograft has an abscopal effect on abscopal tumor growth, although re-implantation of liquid nitrogen-treated bone grafts did not induce a strong T-cell response or tumor-suppressive effect.  相似文献   
112.
Telomere length (TL) influences the development of lifestyle-related diseases, and neonatal TL may influence their prevalence. Various factors have been reported to affect neonatal TL. Although the fetus is exposed to multiple conditions in utero, the main factors affecting the shortening of neonatal TL are still not known. In this study, we sought to identify factors that influence fetal TL. A total of 578 mother-newborn pairs were included for TL analysis. TL was measured in genomic DNA extracted from cord blood samples using quantitative PCR. The clinical factors examined at enrollment included the following intrauterine environmental factors: maternal age, assisted reproductive technology (ART) used, body mass index (BMI), gestational diabetes mellitus (GDM), maternal stress, smoking, alcohol consumption, preterm delivery, small-for-gestational-age, neonatal sex, and placental weight. Univariate and multivariate regression analyses were used to verify the relationship between neonatal TL and these clinical factors. The median neonatal TL to single-copy gene ratio was 1.0. Pregnancy with ART was among the 11 factors associated with shorter neonatal TL. From multiple regression analysis, we determined that neonatal TL was significantly shorter for pregnancies in the ART group than in the other groups. We conclude that pregnancy with ART is associated with shorter neonatal TL.  相似文献   
113.
In recent years, we have experienced mega‐flood disasters in Japan due to climate change. In the last century, we have been building disaster prevention infrastructure (artificial levees and dams, referred to as “grey infrastructure”) to protect human lives and assets from floods, but these hard protective measures will not function against mega‐floods. Moreover, in a drastically depopulating society such as that in Japan, farmland abandonment prevails, and it will be more difficult to maintain grey infrastructure with a limited tax income. In this study, we propose the introduction of green infrastructure (GI) as an adaptation strategy for climate change. If we can use abandoned farmlands as GI, they may function to reduce disaster risks and provide habitats for various organisms that are adapted to wetland environments. First, we present a conceptual framework for disaster prevention using a hybrid of GI and conventional grey infrastructure. In this combination, the fundamental GI, composed of forests and wetlands in the catchment (GI‐1) and additional multilevel GIs such as flood control basins that function when floodwater exceeds the planning level (GI‐2) are introduced. We evaluated the flood attenuation function (GI‐1) of the Kushiro Wetland using a hydrological model and developed a methodology for selecting suitable locations of GI‐2, considering flood risk, biodiversity and the distribution of abandoned farmlands, which represent social and economic costs. The results indicated that the Kushiro Wetland acts as a large natural reservoir that attenuates the hydrological peak discharge during floods and suitable locations for introducing GI‐2 are concentrated in floodplain areas developing in the downstream reaches of large rivers. Finally, we discussed the network structure of GI‐1 as a hub and GI‐2 as a dispersal site for conservation of the Red‐crowned Crane, one of the symbolic species of Japan.  相似文献   
114.
In wet granulation processes, a particle adhesion mediated by a liquid bridge is one of the quite important phenomena. In an actual process, the liquid bridge shows dynamic motion due to continuous motion of the particles. Therefore, understanding of the particle adhesion phenomenon by a dynamic liquid bridge is essential to adequately and precisely control wet granulation processes. This study presents a direct numerical simulation of the particle–particle adhesion by a dynamic liquid bridge. Collision of a dry particle and a wet particle was simulated at various collision angles. In particular, translational and rotational motions of the particle at different collision angles were discussed through comparison with a conventional static liquid bridge force model. As a result, it was found that both translational and rotational motions were largely different between simulation results of the direct numerical simulation and static liquid bridge force model, especially at the tangential collision. To understand these results, we focused on the rotational behavior of the particle and deformation of the liquid bridge. It was concluded that the non-slip behavior of the liquid bridge on the particle surface is a key phenomenon for the particle-particle adhesion by the dynamic liquid bridge at the tangential collision.  相似文献   
115.
Local out-of-plane deformation of CFRP ablator subjected to rapid heating   总被引:1,自引:0,他引:1  
This study investigates local out-of-plane deformation of a carbon fiber reinforced phenolic polymer ablator subjected to very rapid heating. Local out-of-plane deformation was measured using a three-dimensional digital image correlation technique at high temperatures. This was achieved by attaching high temperature resistant random patterns on the specimen surface using a ceramic bond. Additionally, blue filters intended for cutting strong infrared radiation from the specimen were also used. This study then discusses the mechanisms of the local out-of-plane deformation under rapid heating conditions in terms of carbonization, pyrolysis gas occurrence, gas pressure storage, and interlaminar debonding due to gas pressure.  相似文献   
116.
This study examined the processing and mechanical properties of cross-ply and quasi-isotropic composite laminates processed using aligned multi-walled carbon nanotube/epoxy prepreg sheets. Three kinds of CNT/epoxy laminates, ([0°/90°]s, [60°/0°/?60°]s, [0°/45°/90°/?45°]s) were successfully fabricated using aligned CNT/epoxy prepreg sheets. The CNT volume fraction was approximately 10%. No visible void or delamination was observed in composite laminates, and the thickness of each layer was almost equal to that of the prepreg. To evaluate the elastic moduli, E11, E22, and G12, of each ply in the laminates, on-axis and off-axis tensile tests (0°, 45°, 90°) were conducted of aligned CNT/epoxy lamina specimens. The Young’s modulus of CNT/epoxy cross-ply and quasi-isotropic laminates agreed with the theoretical values, which were calculated using classical laminate theory and elastic moduli of CNT/epoxy lamina. The respective failure strains of [0°/90°]s, [60°/0°/?60°]s, and [0°/45°/90°/?45°]s laminates are 0.65, 0.92, 0.63%, which are higher than that of 0° composite lamina (0.5%). Results suggest that the failure strain of 0° layer in composite laminates is improved because of the other layers.  相似文献   
117.
Microsystem Technologies - The interaction stresses (pressure and shear stress) for the (001) surface between a half-space consisting of a homogeneous material and a half-space with a spatially...  相似文献   
118.
The effect of microtexture on diamond transition was examined for graphite starting materials under shock compressions of 50 to 60 GPa and 80 to 90 GPa. Each of the starting materials used in the present study possessed a fully homogeneous microtexture. To distinguish the effect of microtexture from that of other experimental parameters, the shock conditions were standardized for all specimens tested. Three graphite materials—a glassy carbon, a carbon black, and a natural graphite—were selected and shock compressed using a quenching technique to generate conditions common to all samples. Detailed characterization by transmission electron microscopy and electron energy-loss spectroscopy revealed a clear tendency: The lower the crystallinity and crystallite size of the starting graphite, the more easily the graphite transformed to diamond when the transition mechanism was reconstructive.  相似文献   
119.
Supported Co3O4 catalysts were prepared via the calcination of Co-containing hydrogarnet, (Ca3-x Co x )Al2(SiO4)3- y (OH)4y , at 400 °C. Such precursors with various extents of substitution were synthesized from the hydrothermal reaction of a stoichiometric mixture of calcium oxide, amorphous silica, alumina sol, and cobalt hydroxide at 200 °C. It was found that the catalyst consisted of Co3O4, CaO, and mayenite and exhibited a high activity for the combustion of propylene, benzene, and toluene at temperatures below 300 °C.  相似文献   
120.
Previous studies showed that the stable β‐form of molecular compound (MC) crystals having a double‐chain‐length structure is formed in a binary mixture system of 1,3‐dioleoyl‐2‐palmitoyl‐sn‐glycerol (OPO) and 1,3‐dipalmitoyl‐2‐oleoyl‐sn‐glycerol (POP) with a 1:1 concentration ratio of OPO and POP. The use of MC crystals made of POP and OPO for edible applications, such as margarine, is advantageous due to no‐trans, low‐saturated, and high‐oleic fats. Industrial manufacturing technology involves rapid cooling processes, and the kinetic properties of crystallization of MC of OPO and POP are required. In this study, we clarified the crystallization of MC of OPO and POP under rapid cooling at rates of 1–150 °C min?1, using synchrotron radiation time‐resolved X‐ray diffraction and differential scanning calorimetry methods. The main results are as follows: (1) POP and OPO crystallized in separate manners without the formation of MC crystals under rapid cooling (>40 °C min?1), while MC crystals started to form with decreasing rates of cooling in addition to the POP and OPO crystals (<30 °C min?1); (2) metastable and stable forms sub‐α, α, β′, and β of POP and OPO were formed, whereas the MC crystals of β were formed during the cooling processes; and (3) the heating processes after crystallization by rapid cooling caused separate melting of the metastable and stable forms of POP and OPO crystals and the formation of MC crystals of β made of POP and OPO, as well as melting of the MC crystals alone.  相似文献   
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