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排序方式: 共有214条查询结果,搜索用时 15 毫秒
31.
中、日、欧的被试者对河川景观注视过程的比较研究 总被引:1,自引:0,他引:1
在景观认知·评价过程中,如果把眼球运动作为反映大脑所进行的视觉情报处理过程的外部参数,那么眼的运动方式就可能因评价者的生活经验、知识水平甚至价值观和思维方式的不同而产生差异。因此,可以设想被试者的社会文化背景的差异也有可能会从他们对景观的认知方式上得到体现。作为视觉认知中异域文化差异的比较研究之一,运用眼球运动跟踪仪对评价者的景观认知评价过程进行了跟踪测试,并试图通过对认知过程中的注视点分布、注视点数以及注视点的停留时间和注视内容的变化趋势这几个角度的分析比较来探讨社会文化背景的差异如何体现在人类视觉情报信息的收集整理的外部反应中,从而明确在地域特色景观的保留和营造上构成要素的布局方式的意义。 相似文献
32.
Preparation of Aragonite Whiskers 总被引:10,自引:0,他引:10
Yoshio Ota Saburo Inui† Tetsushi Iwashita† Toshihiro Kasuga† Yoshihiro Abe† 《Journal of the American Ceramic Society》1995,78(7):1983-1984
A simple synthetic method for preparing aragonite whiskers has been developed. A suspension of CaCl2 -MgCl2 -Mg(OH)2 with pH ∼9 has been prepared by adding Ca(OH)2 to MgCl2 aqueous solution. CaCO3 whiskers (aragonite phase) have been prepared easily by blowing CO2 -containing gas into the suspension. The whiskers have high aspect ratios ranging from 20 to 80 with diameters of 0.5–1 μm . 相似文献
33.
Yuhei Ogawa Hisao Matsunaga Junichiro Yamabe Michio Yoshikawa Saburo Matsuoka 《International Journal of Hydrogen Energy》2018,43(43):20133-20142
The fatigue limit properties of a carbon steel and a low-alloy CrMo steel were investigated via fully-reversed tension-compression tests, using smooth specimens in air and in 115-MPa hydrogen gas. With respect to the CrMo steel, specimens with sharp notches were also tested in order to investigate the threshold behavior of small cracks. The obtained SN data inferred that the fatigue limit was not negatively affected by hydrogen in either of the steels. Observation of fatigue cracks in the unbroken specimens revealed that non-propagating cracks can exist even in 115-MPa hydrogen gas, and that the crack growth threshold is not degraded by hydrogen. The experimental results provide justification for the fatigue limit design of components that are to be exposed to high-pressure hydrogen gas. 相似文献
34.
Saburo Hosokawa 《Materials Research Bulletin》2008,43(11):3140-3148
The reaction of yttrium acetate hydrate in 1,2-propanediol at 300 °C yielded a product containing acetate groups and glycol moieties. From this product, Y2O3 was directly crystallized at 400 °C without the formation of a carbonate oxide phase. The thus-obtained Y2O3 samples had a small crystallite size (2.2 nm) and significantly large surface area (280 m2/g). Other nanocrystalline rare earth (Gd-Yb) oxides were also obtained by this method. 相似文献
35.
The effect of water concentration on the foaming tendency of lubricating oil containing the detergent additives Ca-phenate and amide was investigated from a surface chemical standpoint. Foam volume, dynamic surface tension and surface viscosity were measured at various water concentrations. It was proved that the increase of surface viscosity with water content was the main factor affecting foaming in the case of Ca-phenate but, in contrast, the Marangoni effect played an essential role in the case of amide. 相似文献
36.
Sheet metal forming simulation in industry 总被引:32,自引:0,他引:32
A. Makinouchi 《Journal of Materials Processing Technology》1996,60(1-4):19-26
In order to see actual present situation of finite element simulation system introduced to industry to be utilized at the stamping tool design section, four different examples are introduced. It is clearly shown from the example that each industry has its own purpose to the simulation; prediction of wrinkle, prediction of surface deflection, study of tearing limit condition, determination of blank geometry, prediction of springback, evaluation of sheet thickness and residual stress, and so on. Present state of simulation systems integrated into CAD is also investigated. 相似文献
37.
Akira Yamamoto Kentaro Teramura Saburo Hosokawa Tsunehiro Tanaka 《Science and Technology of Advanced Materials》2015,16(2)
The effect of SO2 gas was investigated on the activity of the photo-assisted selective catalytic reduction of nitrogen monoxide (NO) with ammonia (NH3) over a TiO2 photocatalyst in the presence of excess oxygen (photo-SCR). The introduction of SO2 (300 ppm) greatly decreased the activity of the photo-SCR at 373 K. The increment of the reaction temperature enhanced the resistance to SO2 gas, and at 553 K the conversion of NO was stable for at least 300 min of the reaction. X-ray diffraction, FTIR spectroscopy, thermogravimetry and differential thermal analysis, x-ray photoelectron spectroscopy (XPS), elemental analysis and N2 adsorption measurement revealed that the ammonium sulfate species were generated after the reaction. There was a strong negative correlation between the deposition amount of the ammonium sulfate species and the specific surface area. Based on the above relationship, we concluded that the deposition of the ammonium sulfate species decreased the specific surface area by plugging the pore structure of the catalyst, and the decrease of the specific surface area resulted in the deactivation of the catalyst. 相似文献
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Mining frequent itemsets from large databases has played an essential role in many data mining tasks. It is also important to maintain the discovered frequent itemsets for these data mining tasks when the database is updated. All algorithms proposed so far for the maintenance of discovered frequent itemsets are only performed with a fixed minimum support,which is the same as that used to obtain the discovered frequent itemsets. That is, users cannot change the minimum support even if the new results are unsatisfactory to the users. In this paper two new complementary algorithms, FMP (First Maintaining Process) and RMP (Repeated Maintaining Process), are proposed to maintain discovered frequent itemsets in the case that new transaction data are added to a transaction database. Both algorithms allow users to change the minimum support for the maintenance processes. FMP is used for the first maintaining process, and when the result derived from the FMP is unsatisfactory, RMP will be performed repeatedly until satisfactory results are obtained. The proposed algorithms re-use the previous results to cut down the cost of maintenance. Extensive experiments have been conducted to assess the performance of the algorithms. The experimental results show that the proposed algorithms are very resultful compared with the previous mining and maintenance algorithms for maintenance of discovered frequent itemsets. 相似文献