全文获取类型
收费全文 | 224篇 |
免费 | 6篇 |
专业分类
电工技术 | 14篇 |
化学工业 | 59篇 |
金属工艺 | 6篇 |
机械仪表 | 6篇 |
建筑科学 | 1篇 |
能源动力 | 12篇 |
轻工业 | 18篇 |
水利工程 | 1篇 |
无线电 | 21篇 |
一般工业技术 | 35篇 |
冶金工业 | 39篇 |
原子能技术 | 6篇 |
自动化技术 | 12篇 |
出版年
2022年 | 2篇 |
2021年 | 4篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 7篇 |
2015年 | 6篇 |
2014年 | 3篇 |
2013年 | 9篇 |
2012年 | 4篇 |
2011年 | 7篇 |
2010年 | 9篇 |
2009年 | 12篇 |
2008年 | 13篇 |
2007年 | 6篇 |
2006年 | 6篇 |
2005年 | 9篇 |
2004年 | 5篇 |
2003年 | 3篇 |
2002年 | 16篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 7篇 |
1998年 | 17篇 |
1997年 | 9篇 |
1996年 | 5篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 10篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 5篇 |
1976年 | 2篇 |
1972年 | 3篇 |
1969年 | 1篇 |
排序方式: 共有230条查询结果,搜索用时 109 毫秒
131.
Onoda S. Tsukamoto N. Ogino M. Yamashita K. Yumoto O. Inoue K. Komatsu Y. 《Photonics Technology Letters, IEEE》2008,20(9):688-690
A new temperature sensing system, which utilizes a thin-film bandpass filter deposited on an optical fiber end face and dual-wavelength push-pull reflectometry, is proposed. The system has the following advantages over the fiber Bragg grating sensor: it can observe the temperature in a localized small area and it gets rid of microcrack growth caused by stripping of cover coating from a fiber. The feasibility of the system has been verified by simulation. 相似文献
132.
Yosuke Yamazaki Yohei Abe Yukio Hioki Tomohiro Tanaka Mitsuyoshi Nakatani Akikazu Kitagawa 《Welding International》2017,31(1):38-47
The oscillation laser beam is considered to be effective as a heat source of narrow gap multi-layer welding because oscillation laser welding can control the penetration shape and prevent the lack of fusion. In this study, in order to establish a narrow gap welding process by oscillation laser beam, butt welding experiments of 50 mm thickness carbon steel plate were performed. By the appropriate control of the heat input area using the in-process sensor for recognizing the groove shape, narrow gap welding of a thick plate with groove which was cut by gas cutting was achieved. Properties of the welded joint had been confirmed by nondestructive testing, tensile test and side bend test. A two-dimensional numerical calculation model for welding deformation was developed. This calculation model was used for investigation of the optimal groove angle. The results of calculations were in quantitative agreement with the experimental results. Microstructure of the weld zone had multiple thermal histories. According to the hardness test results, maximum hardness of the heat affected zone of the upper layer has been lowered than that of the lower layer. 相似文献
133.
The electrophoretic deposition is a method useful to prepare conjugated polymer films for electronic devices. This method provides high material recovery rate on the substrate from the suspension, in contrast to the conventional spin-coating in which most of the material placed on the substrate is blown away. Although manual reprecipitation technique successfully yields suspensions of various conjugated polymers including polyfluorene derivatives, it is favorable to control the preparation process of suspensions. In this context, this paper reports preliminary results on the preparation of suspension of conjugated polymer by using an ultrasonic atomizer. While the resultant films do not show particular difference due to the preparation methods of the suspension, the electric current profiles during the electrophoretic deposition suggests that the ultrasonic atomization of polymer solution prior to be mixed with poor solvent results in smaller and less uniform colloidal particles than the conventional manual pouring method. 相似文献
134.
Maleic anhydride was grafted onto poly(propylene) (PP)‐type thermoplastic elastomer PER by reactive processing with a screw extruder and a maleated PER (MPER) was prepared. With the intent of ionic crosslinking, metal compounds such as aluminum stearate (AlSt), magnesium stearate (MgSt), calcium stearate (CaSt), zinc stearate (ZnSt), potassium stearate (KSt), sodium stearate (NaSt), magnesium hydroxide (MH), zinc oxide (ZnO), and zinc sulfide (ZnS) were added to the MPER and melt‐mixed with the screw extruder, and crosslinked compounds were obtained. The degree of crosslinking estimated from the gel fraction was in the order AlSt, MgSt, CaSt, ZnSt > NaSt, KSt > MH > ZnO, ZnS > MPER. The rheological properties, such as capillary flow properties and dynamic viscoelasticities, of the compounds were measured and their melt processabilities were evaluated. The viscosity increased with increasing the content of the metal compounds and the increase was higher at the lower shear rate. The increasing effect of the viscosity at low shear rates was AlSt > MgSt > ZnSt > NaSt > KSt > MH > ZnO > ZnS > MPER. Namely, the viscosity increasing effect of the metal salt of stearic acid is the higher for the larger ionic charge and the viscosity increasing effects of other compounds are lower than those of the metal salts of stearic acid. Accordingly, by changing the kind and content of the metal compounds, the viscosity can be freely controlled. Considering also other rheological characteristics, these ionically crosslinked compounds are assumed to show ideal flow processabilities except for the extrudate appearance. To improve the appearance, it is necessary to dilute the compound with unmodified PER, PP, or fillers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2887–2897, 2002 相似文献
135.
To develop new photoinduced electron-transfer (PET) reagents, we established a method for predicting the fluorescence quantum yields (phi) of the benzofurazan compounds bearing an aliphatic substituent group having an n-electron. The PET process occurred sufficiently to reduce the phi values in the benzofurazan compounds bearing an aliphatic moiety, which had a high quenching ability. The quenching ability was estimated by the molecular orbital calculation and Stern-Volmer plotting. The phi values of the benzofurazan compounds could be controlled by changing the quenching ability of a substituent group. We succeeded in designing a PET reagent for peroxyacetic acid (PAA), 4-ethylthioacetylamino-7-phenylsulfonyl-2,1,3-benzoxadiazole (EPB), using the established method for predicting the phi values. EPB and its oxidized derivative were separated by reversed-phase HPLC and fluorometrically detected at 479 nm with excitation at 362 nm. The attained detection limit for PAA was 105 fmol (S/N = 3) and the cross-reactivity toward hydrogen peroxide was very low, indicating EPB is a highly sensitive and selective reagent for PAA. 相似文献
136.
Takashi Kobayashi Sen'ichi Onoda Norihisa Komoda 《Information Technology and Management》2002,3(1-2):43-66
The reuse of business-process and information specifications can reduce the cost of business design by helping to alleviate bottlenecks in the development of workflow systems. Using a new concept we call workflow design pattern, we create a library of standard business-process and information specifications to be used as workflow business template. Business design and system design are done by customizing the standard specifications. New support tools are used to implement the design result. By using this proposed method, the cost of system development can be reduced. 相似文献
137.
Inaba Hiromi Onoda Yoshimitsu Shima Seiya Ando Takeki Kurosawa Toshiaki Sakai Yoshio Maekawa Toshiaki 《Industry Applications, IEEE Transactions on》1980,(2):179-185
A circuit with a unidirectional armature current and bidirectional field current was used in order to realize a high-reliability speed-control system for dc motors by simplifying the armature circuit construction in comparison with conventional Thyristor-Leonard speed-control systems. In making the new circuit feasible, we developed a system in which either armature current or field current is fixed and the other varies depending on the magnitude of the torque command; a high-reliability magnetically controlled three-phase thyristor amplifier; and minor feedback loops provided with a field current control circuit and armature current control circuit. By using these techniques, we developed a dc motor control system that features higher reliability and smaller power consumption than conventional control systems. The new system was applied to elevator control with good results. 相似文献
138.
目前,我国建筑策划类项目对"后评估"的研究已日臻成熟;但在实践方面,"前策划"仍较少介入设计项目,为科学、合理的建筑项目定位及其实现的全过程提供指导.仙台媒体中心自建成至今的20年内,始终作为地标性公共文化建筑为市民活动提供重要场所,为区域环境营造提供巨大助力.文章以仙台媒体中心策划项目实践全过程为研究对象,从其项目定位的内容、采取的策划举措、建成后使用测度及前馈三方面进行分析,对其如何进行科学定位、支持定位实现的有效策划途径进行总结,以期为我国的建筑策划实践提供借鉴. 相似文献
139.
High performance-anatase TiO2 films were successfully formed on metallic titanium by anodization in an acidic electrolyte composed of H2SO4, H3PO4 and H2O2 subsequent to pre-nitridation treatment. The pre-nitridation treatment was carried out by pre-annealing metallic titanium under a nitrogen atmosphere of 0.1 MPa. The anodized films showed photocatalytic activity in photooxidization of the iodide anion into the tri-iodide anion. The nitridation treatment had a significant effect not only on the formation of anatase TiO2 films but also on the photocatalytic activity of the anodized films. 相似文献
140.
Mitsuyoshi Onoda Daisuke Fujita Kenichiro Isaki Hiroshi Nakayama 《Electrical Engineering in Japan》1999,128(1):1-8
By exposing low‐density polyethylene to an atmosphere of fuming sulfuric acid, sulfonated low‐density polyethylenes (SPE) were prepared and the degree of surface sulfonation of the treated film was determined from the weight increase per unit area. Polypyrrole (PPy) films on the surface of SPE were grown by molecular self‐assembly and the properties of PPy/SPE composite films were investigated. Functional applications of PPy/SPE composite films are proposed, with particular attention to the movement properties of actuators using PPy/SPE composite films. © 1999 Scripta Technica, Electr Eng Jpn, 128(1): 1–8, 1999 相似文献