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51.
Improved heat and solvent resistance of a pressure‐sensitive adhesive thermally processable by isocyanate dimer dissociation 下载免费PDF全文
Methods that do not involve use of an organic solvent are being considered for manufacturing environmental‐friendly pressure‐sensitive adhesive tapes. Among these methods, the hot‐melt method exhibits high productivity but is somewhat limited in terms of performance. Hot‐melt‐fabricated pressure‐sensitive adhesives require heating fluidization and cooling solidification, and it is extremely difficult to improve their heat resistance. We examine thermally processable pressure‐sensitive adhesives with a completely new structure, fabricated based on the thermal dissociation of the isocyanate dimer. This enables thermal processing of materials softened by thermal dissociation. Fabrication of crosslinkable pressure‐sensitive adhesive becomes possible through a reaction of isocyanate caused by dissociation of its dimer. It is found that improving thermal and solvent resistances, which are disadvantages associated with conventional hot‐melt pressure‐sensitive adhesives, is potentially possible with the pressure‐sensitive adhesive reported here. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41444. 相似文献
52.
Synthesis of Succinic Gemini Surfactants and the Effect of Stereochemistry on Their Monolayer Behaviors 下载免费PDF全文
Tokuzo Kawase Maiko Kagawa-Ohara Tsunetomo Aisaka Tatsuo Oida 《Journal of surfactants and detergents》2015,18(4):615-627
In this work, succinic gemini surfactants, dl‐ and meso‐2,3‐bis(alkyl)succinic acids (alkyl: C6H13–C13H27), were successfully synthesized by oxidative coupling of enolates of fatty acid tert‐butyl esters with copper(II) bromide followed by treatment with CF3COOH. Focusing on the influence of stereochemistry (dl‐ and meso‐) of succinic geminis, their monolayer behaviors at the air–water interface were explored using surface pressure–area (Π–A) isotherms, the compression modulus of monolayers (εs), and Brewster angle microscope (BAM) analysis. meso‐2,3‐Bis(undecyl)succinic acid showed a unique isotherm where the surface pressure drastically decreased at A = ~0.56 nm2 (Π = 21.9 mN m?1) regardless of compression rates and subphase temperatures, while dl‐isomer showed the common isotherm of gas → liquid‐expanded → liquid‐condensed phase transitions. BAM analysis on meso‐2,3‐bis(undecyl)succinic acid films at the air–water interface showed that small islands of aggregates appear just after the maximum pressure (A = ~0.56 nm2), and on further compression needle‐shaped assemblies appear that can grow in size. It was reasonably concluded that hydrophobic interactions can operate more effectively in meso‐isomers than in dl‐isomers, and that meso‐molecules can “jump up” to cause a transition from monolayer to bilayer. This is the first finding of the “jumping‐up” phenomenon of gemini surfactants having meso‐stereochemistry. 相似文献
53.
Takahiro Mise Shin Tajima Tatsuo Fukano Kazuo Higuchi Tsukasa Washio Kazuo Jimbo Hironori Katagiri 《Progress in Photovoltaics: Research and Applications》2016,24(7):1009-1015
We have investigated the influence of sodium (Na) on the properties of co‐evaporated Cu2ZnSnS4 (CZTS) layer microstructures and solar cells. The photovoltaic performance and diode properties were improved by incorporating Na from NaF layers into the CZTS layers, while Na had a negligible effect on the microstructural properties of the layer. The best cell fabricated by using an optimal CZTS layer (Cu/(Zn + Sn) = 0.70, Zn/Sn = 1.8) yielded an active area efficiency of 5.23%. The analysis of device properties suggests that charge‐carrier recombination at CZTS/CdS interface is suppressed by intentional Na incorporation from NaF layers. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
54.
55.
Sejoon Oh Tatsuya Miyashita Tatsuo Uchida 《Journal of the Society for Information Display》2011,19(1):106-109
Abstract— The adsorption strength of liquid‐crystal molecules on the alignment‐layer (polymer) surface was judged measuring temperature dependence of birefringence of an absorbed liquid‐crystal layer above the nematic—isotropic transition temperature. The relationship between the surface‐order parameter and the adsorption strength of liquid‐crystal molecules on the non‐rubbed polymer surface was also discussed. 相似文献
56.
Tatsuo Sakamoto Katsutoshi Kuribayashi Kousei Murakami 《Artificial Life and Robotics》2000,4(3):167-170
In a die-casting operation, the die spray is the key to quality and productivity, but the die-spray operation depends on parameter
settings such as the spray volume and the operator's experience, even when a robot sprayer is used. The purpose of this study
was to establish an intelligent system to control the surface temperature of a die with a water-based mist spray. A fuzzy
model was applied to determine the optimum mist spray volume. The results generated show a good match with the actual measurements
of the rate of the temperature drop versus the spray-mist volume. After the fuzzy analysis, the spray parameters calculated
were used to control an actual die temperature experiment conducted on a heated plate model. The fuzzy model constructed by
using fundamental experiments allowed the die spray operation to maintain a predetermined spray volume.
This work was presented in part at the Fourth International Symposium on Artificial Life and Robotics, Oita, Japan, January
19–22, 1999 相似文献
57.
Norihito Mayama Hiroyuki Yoshida Tatsuo Iwata Kaoru Sasakawa Atsushi Suzuki Yuya Hanaoka Yoshihiro Morita Akito Kuroda Masanori Owari 《Diamond and Related Materials》2010,19(7-9):946-949
In this study, we report the characterization of carbonaceous films deposited on metal substrates by liquid-phase electrodeposition in methanol. The characterization of carbonaceous films by electrodeposition was examined by means of Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), electron energy loss spectroscopy (EELS), secondary ion mass spectrometry (SIMS), atom probe (AP) and high resolution-elastic recoil detection analysis (HR-ERDA). From these results, it was found that the films deposited on the metal substrates were composed of the sp2 and sp3 carbon contents, of which the ratio was about 7:3. Furthermore, the films by electrodeposition contained much hydrogen. The hydrogen contents in the surface were about 60 at.% and those in the subsurface were a few 10 at.%. 相似文献
58.
59.
Mitomi O. Kasaya K. Tohmori Y. Suzaki Y. Fukano H. Sakai Y. Okamoto M. Matsumoto S. 《Lightwave Technology, Journal of》1996,14(7):1714-1720
Structures of spot size converters that allow low loss and easy coupling between an optical semiconductor device and a fiber are proposed and designed theoretically. These spot-size converters have a tapered small core for expanding the mode field. They also have a double cladding region which consists of an n+-doped InP substrate as the outer cladding and a p-doped or nondoped InP layer as the inner cladding with a ridge structure. This double cladding utilizes the plasma effect of a carrier which makes the refractive index of highly doped n-InP lower than that of p-doped or nondoped InP. The double-cladding structure can tightly confine an expanded mode field in the inner cladding, and results in low radiation loss at the tapered waveguide, in addition, this structure reforms the mode field shape into a Gaussian-like shape and achieves a low loss coupling of less than 1 dB with a large misalignment tolerance for fiber coupling. These spot-size converters are easily fabricated and applicable to all types of optical semiconductor devices 相似文献
60.
Tatsuo Yamauchi 《应用聚合物科学杂志》2006,100(4):2895-2900
The local heat generation that accompanied tensile drawing of polymer films was successfully observed by infrared thermography as a series of temperature distribution images. These images showed that the high temperature part where rearrangements of molecular orientation and microcrystallines occurred was located mainly at the end of the necked part for the polymers that exhibited necking or appeared uniformly throughout films for the polymers that did not exhibit necking. The generated heat could be roughly estimated, and the relation between the estimated heat and mechanical work led to the thermodynamic investigation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2895–2900, 2006 相似文献