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排序方式: 共有587条查询结果,搜索用时 15 毫秒
1.
Kazuki Hirose Miho Kuwahara Eiji Nakata Tomonori Tetsunaga Kazuki Yamada Kenta Saiga Masaharu Takigawa Toshifumi Ozaki Satoshi Kubota Takako Hattori 《International journal of molecular sciences》2022,23(23)
Osteoarthritis (OA) occurs not only in the knee but also in peripheral joints throughout the whole body. Previously, we have shown that the expression of cellular communication network factor 3 (CCN3), a matricellular protein, increases with age in knee articular cartilage, and the misexpression of CCN3 in cartilage induces senescence-associated secretory phenotype (SASP) factors, indicating that CCN3 promotes cartilage senescence. Here, we investigated the correlation between CCN3 expression and OA degenerative changes, principally in human femoral head cartilage. Human femoral heads obtained from patients who received total hip arthroplasty were categorized into OA and femoral neck fracture (normal) groups without significant age differences. Gene expression analysis of RNA obtained from femoral head cartilage revealed that CCN3 and MMP-13 expression in the non-weight-bearing part was significantly higher in the OA group than in the normal group, whereas the weight-bearing OA parts and normal cartilage showed no significant differences in the expression of these genes. The expression of COL10A1, however, was significantly higher in weight-bearing OA parts compared with normal weight-bearing parts, and was also higher in weight-bearing parts compared with non-weight-bearing parts in the OA group. In contrast, OA primary chondrocytes from weight-bearing parts showed higher expression of CCN3, p16, ADAMTS4, and IL-1β than chondrocytes from the corresponding normal group, and higher ADAMTS4 and IL-1β in the non-weight-bearing part compared with the corresponding normal group. Acan expression was significantly lower in the non-weight-bearing group in OA primary chondrocytes than in the corresponding normal chondrocytes. The expression level of CCN3 did not show significant differences between the weight-bearing part and non-weight-bearing part in both OA and normal primary chondrocytes. Immunohistochemical analysis showed accumulated CCN3 and aggrecan neoepitope staining in both the weight-bearing part and non-weight-bearing part in the OA group compared with the normal group. The CCN3 expression level in cartilage had a positive correlation with the Mankin score. X-ray analysis of cartilage-specific CCN3 overexpression mice (Tg) revealed deformation of the femoral and humeral head in the early stage, and immunohistochemical analysis showed accumulated aggrecan neoepitope staining as well as CCN3 staining and the roughening of the joint surface in Tg femoral and humeral heads. Primary chondrocytes from the Tg femoral head showed enhanced expression of Ccn3, Adamts5, p16, Il-6, and Tnfα, and decreased expression of Col2a1 and -an. These findings indicate a correlation between OA degenerative changes and the expression of CCN3, irrespective of age and mechanical loading. Furthermore, the Mankin score indicates that the expression level of Ccn3 correlates with the progression of OA. 相似文献
2.
Extension of the applicable range of the implicit curve-fitting method for refrigerant thermodynamic properties to critical pressure 总被引:2,自引:1,他引:2
Guo Liang Ding Zhigang Wu Kaijian Wang Masaharu Fukaya 《International Journal of Refrigeration》2007,30(3):418-432
The method of implicit curve-fitting and explicit-calculation has been used for fast and stable calculations of thermodynamic properties of subcritical refrigerants. In order to extend that method to the critical pressure, a method of sectional implicit curve-fitting and explicit-calculation for refrigerant thermodynamic properties is introduced in this paper. The whole data range is divided into several subsections. The requirements on the continuity of thermodynamic properties and the first order derivative of thermodynamic properties in the intersection points of subsections are indicated, and the methods to meet the requirements are presented. Quadric equations are constructed instead of curve-fitting when no data can be given. With the source data obtained from REFPROP 7.1, explicit fast calculation formulae for thermodynamic properties of R410A, covering the saturated temperature of 213.15–344.51 K and superheat of 0–65 K, are given as an example. The calculation speeds of the formulae of R410A are more than 7000 times faster than those of REFPROP 7.1 while the total mean relative deviation of the fast calculation formulae from REFPROP 7.1 is only 0.04%. 相似文献
3.
Yosuke Kimura Masaharu Asano Ryoichi Katakai 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,263(2):463-467
Poly(ethylene-co-tetrafluoroethylene) (ETFE) films were irradiated by swift heavy ion-beams of 129Xe23+ with fluences of 0, 3 × 106, 3 × 107, 3 × 108 and 3 × 109 ions/cm2, followed by γ-ray pre-irradiation for radiation grafting of styrene onto the ETFE films and sulfonation of the grafted ETFE films to prepare highly anisotropic proton-conducting membranes. The fluence of Xe ions and the addition of water in the grafting solvent were examined to determine their effect on the proton conductivity of the resultant membranes. It was found that the polymer electrolyte membrane prepared by grafting the styrene monomer in a mixture of 67% isopropanol and 33% water to the ETFE film with an ion-beam irradiation fluence of 3.0 × 106 ions/cm2 was a highly anisotropic proton-conducting material, as the proton conductivity was three or more times higher in the thickness direction than in the surface direction of the membrane. 相似文献
4.
Using the instrumented fuel assemblies (IFA) installed in the Japan Power Demonstration Reactor (JPDR)-II core, fluctuations of the inlet and outlet channel flow rates were observed under both conditions of at-power operation and cold core flow circulation. The correlation analysis revealed that the flow fluctuations in any IFA channel showed almost uncorrelated cross-covariance function with other IFA channel flow. To explain the mechanism of the channel flow fluctuations, some hypothetical idea is introduced. 相似文献
5.
Susumu Onaka Satoshi Soeta Masaharu Kato Ryohei Tanaka 《Journal of Materials Science》1988,23(2):577-582
Bicrystals of CU-SiO2 dispersion-hardened alloys and of pure copper were tensile tested at various temperatures between 450 and 1050 K at a strain rate of 1.5 x 10–4 sec–1. In the case of pure copper bicrystals, elongation to fracture did not depend significantly on temperature and the fracture mode was invariably transgranular up to 850 K. On the other hand, the ductility of CU-SiO2 bicrystals decreased with increase in temperature and the transition in the fracture mode from transgranular to intergranular occurred at around 450 K. SiO2 particles on grain boundaries play an important role on intergranular fracture by suppressing grain-boundary sliding and also on the retardation of recrystallization during deformation. Two types of Cu-SiO2 bicrystals having different crystal orientation relationships show quite different deformation and fracture behaviour. This can be explained in terms of the contribution of lattice dislocations to the grain-boundary sliding. 相似文献
6.
Masaharu Kamei Sumiko Ohgaki Tamotsu Kanbe Isao Niiya Haruo Mizutani Isao Matsui-Yuasa Shuzo Otani Shigeru Morita 《Lipids》1995,30(6):533-539
We investigated the relationship between dietary highly hydrogenated soybean oil (HSO) and cholesterol transport in rats.
In the first study, to examine the effects of cholesterol transport of different concentrations of HSO in dietary oil, rats
were given one of the three diets containing 0, 25, or 50% HSO in dietary oil with cholesterol (5 g/kg diet) or a diet without
HSO and cholesterol for 22 d. Feeding the high concentration of HSO prevented the increase in plasma total cholesterol, hepatic
total lipids, and cholesterol and the decrease in high-density lipoprotein-cholesterol, which were caused by dietary cholesterol.
Moreover, HSO increased the fecal excretion, fecal lipids, and steroids in a dose-dependent manner. In the second study, to
examine the effects on cholesterol transport of redistribution of stearic acid in the triacylglycerol species contained in
HSO, rats were given one of the six diets containing HSO (distearoylmonoacylglycerol and tristearoylglycerol)-rich, monostearoylglycerol-rich,
or palmitic acid-rich oil with/without cholesterol (5 g/kg diet), for 30 d. Whereas the accumulation of cholesterol in the
body was reduced, cholesterol excretion was enhanced effectively in rats given the HSO-rich diet compared with rats given
the monostearoylglycerol-rich diet. These results suggested that not only the high concentration of stearic acid but also
its uneven distribution in HSO-triacylglycerol contributed to the reduction in intestinal cholesterol absorption in rats. 相似文献
7.
町屋是日本传统的联排别墅形式,从江户时代起盛行,目前京都还保留了一些町屋.京都町屋的特征之一是狭窄的正面和被称为"鳗鱼床"(Unaginonedoko)的深处.京都现在的町屋经常被改造成商店或旅馆. 相似文献
8.
Yoshihiko Hibi Katsuyuki Fujinawa Seiji Nishizaki Kazuo Okamura Masaharu Tasaki 《Soils and Foundations》2010,50(1):143-159
Diffusion, dispersion, and advection are important processes in multi-gas systems in soils. To date, both Fick's model and the Dusty Gas (DG) model have been used to model the movement of gases in these systems. Dispersion is included in the dispersion-advection equation with Fick's Model for the movement of gases in gas-phase of soil, yet the movement of gases in multi-component gas-soil systems is considered to be expressed more accurately by the DG model than by Fick's model. However to date, no study has investigated the necessity of considering dispersion in the Dusty Gas (DG) model. We carried out column experiments for nitrogen-methane, nitrogen-carbon dioxide, and carbon dioxide-methane binary gas systems in sandy soil, and also did simulations on the same systems using both Fick's model and the DG model. A comparison of the results of the column experiments with our simulations confirmed that there was no need to consider the dispersion in the advection-diffusion equations with the DG model when the velocity of gas was 0.05-0.4 cm/s in Toyoura sand. Furthermore, our experiments and simulations with the DG model showed that, rather than dispersion, tortuosity should be taken into account in application of the DG model to the above condition. 相似文献
9.
10.
In this study, microbial precipitation of carbonate was observed using high microbial urease activity, and it was found that the ratio of Mg/Ca affected the types of crystals produced. Without Mg2+, calcite was produced using only CaCl2, while the presence of Mg produced Mg-calcite, magnesite and/or possibly dolomite of round, spherical or fibrous shapes, depending on reaction time, pH and Mg/Ca ratio. The carbonate produced contributed to the development of cementation for sands. The presence of Mg showed a relatively strong cementation of the carbonate. 相似文献