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951.
952.
Takemitsu Kunio Jr. Tomoki Nishino Eiji Ohta Makoto Sakata 《Solid-state electronics》1981,24(12):1087-1091
The energy levels and the degeneracy ratios for chromium in silicon have been determined by the Hall coefficients which were measured by the van der Pauw method. Using the curve fitting method for carrier concentration based on the charge balance equation with the root mean square deviation, the analysis shows that chromium in silicon gives rise to two donor levels. The energy levels of the upper and lower donors are located at Ec-0.226(±0.010)eV and Ev+0.128(±0.005)eV, and their degeneracy ratios are 1/3 and 1/4, respectivel 相似文献
953.
Satoh K Takizawa R Sarai M Sato N Takahashi R Tokuyama T 《Journal of Bioscience and Bioengineering》2004,98(3):207-210
Two kinds of ammonia-oxidizing bacteria isolated from biologically deodorizing plants in cold districts in Japan were identified as Nitrosomonas sp. IWT202 and Nitrosomonas sp. IWT514. The optimum pHs for growth were 8.0 (IWT202) and 7.5 (IWT514). Although rockwool samples for isolation were collected from the same plants, the optimum temperature for growth of strain IWT202 (37 degrees C) differed from that of strain IWT514 (30 degrees C). The bacteria had a higher (IWT202, 37 degrees C) and lower (IWT514, 20 degrees C) growth temperature than is usually the case. Both strains were shown to differ completely in regard to the effect of the ammonium sulfate concentration in the medium for a 20 degrees C culture and 30 degrees C culture. The inoculation of these bacteria provides the possibility of recovering ammonia-oxidizing activity, when the ammonia-oxidizing activity is lowered in biological deodorizing plants in cold districts. It seems that these strains are suitable for application to deodorization. 相似文献
954.
Haruhiko Ohta Shigenori Yamaguchi Yoshihiko Ito Yasuhisa Shinmoto Yoshiyuki Abe 《Microgravity science and technology》2007,19(3-4):141-143
To develop high-performance space thermal management systems using boiling phenomena, the heat transfer characteristics of low concentration alcohol aqueous solutions were investigated on ground. For mixtures of 1-Propanol/Water, 2-Propanol/Water and Water/1-Butanol, i.e. substantially positive mixtures at very low concentration range of alcohol, heat transfer enhancement was observed, while only heat transfer deterioration was reported in most of existing studies for nucleate boiling of mixtures. A concept of coexisting heat transfer enhancement due to Marangoni effect additionally to the heat transfer deterioration due to mass transfer resistance was emphasized. The concept seems to be true for mixture nucleate boiling independent of gravity level. 相似文献
955.
Claudio Naoto Fuzitaki Paulo Blauth Menezes Júlio Pereira Machado Fernando D’Andrea 《The Journal of supercomputing》2006,36(1):51-81
Nautilus is a high-level specification and programming language having abstraction mechanisms not commonly found in other
programming languages inspired by its semantic domain (a categorial model named Nonsequential Automata). It constitutes an
elegant solution for concurrency and non-determinism as well as for synchronization of concurrent systems. The role as specification
language highlights the diagrammatic syntax (it was originally text based).The diagrammatic syntax for Nautilus allows complete
programs to be written using symbols and graphical diagrams. The graphical notation was elaborated in order to be able to
express all the structures in the language, yet trying to improve the visualization of written programs. A brief comparison
with UML is included. To support Nautilus as a programming language, a mapping to Java is constructed, setting the basis for
an execution environment of Nautilus specifications. 相似文献
956.
Naoto Abe Mineichi Kudo Jun Toyama Masaru Shimbo 《Pattern Analysis & Applications》2006,9(2-3):127-137
Feature selection aims to choose a feature subset that has the most discriminative information from the original feature set. In practical cases, it is preferable to select a feature subset that is universally effective for any kind of classifier because there is no underlying information about a given dataset. Such a trial is called classifier-independent feature selection. We took notice of Novovičová et al.’s study as a classifier-independent feature selection method. However, the number of features have to be selected beforehand in their method. It is more desirable to determine a feature subset size automatically so as to remove only garbage features. In this study, we propose a divergence criterion on the basis of Novovičová et al.’s method. 相似文献
957.
Catalysis Letters - Two tungstates containing platinum nanoparticles (Pt Npts) were obtained by air-calcining α-Keggin-type diplatinum(II)-coordinated polyoxotungstates,... 相似文献
958.
Hui-Li Li Rong-Jun Xie Naoto Hirosaki Takashi Takeda Guo-Hong Zhou 《International Journal of Applied Ceramic Technology》2009,6(4):459-464
Eu2+ -doped M2 Si5 N8 (M=Ca, Sr, Ba) orange–red phosphors were successfully prepared by a simple, direct, and efficient solid-state reaction using air-stable MSi2 , Eu2 O3 , and α-Si3 N4 as the starting materials under N2 –H2 (5%) atmosphere. The influence of the type of the alkaline-earth ion on the phase structure and luminescence properties has been investigated. The results show that the synthesized powders have a single-phase crystal structure of M2 Si5 N8 for M=Ca, Sr, and a little amount of BaSi7 N10 impurity phase for M=Ba. Under the blue light excitation, M2 Si5 N8 :Eu2+ shows a typical broad band emission of Eu2+ ranging from orange to red (585–620 nm) depending on the type of M ion. The emission intensity, conversion efficiency, and thermal stability increase with the sequence of Ca2 Si5 N8 :Eu2+ has the highest application potential as a red conversion phosphor for white light-emitting diodes. 相似文献
959.
Kazuhisa Inaba Kouji Saida Pradip Ghosh Ken Matsubara Munisamy Subramanian Akari Hayashi Yasuhiko Hayashi Masaki Tanemura Masashi Kitazawa Ryo Ohta 《Carbon》2011,49(13):4191-4196
A single amorphous carbon nanofiber (CNF) was grown on a commercial Si cantilever by the argon ion (Ar+) bombardment of carbon coated silicon cantilever. The CNF probe was mounted on a piezo controlled arm opposing a soft cantilever to measure the axial force acting on the CNF in a scanning electron microscope (SEM). The buckling force was measured while observing the buckling behavior. The CNF probes have an elliptical cross section with short and long axis of 20–29 and 25–59 nm, respectively, and a length of 350–760 nm. The Young’s modulus was determined from Euler’s formula using the measured buckling force and had a value of 38–48 GPa, almost independent of the CNF size. The Young’s modulus was lower than that of high quality carbon nanotubes (CNTs) and higher than that of defective CNTs. It was also demonstrated that the CNF probes were elastic, similar to the CNT probes. Thus CNF probes produced by Ar+ ion bombardment are quite promising as practical nanocarbon probes. 相似文献
960.
Tomohisa Kinami Naoto Horii Bhaskar Narayan Shingo Arato Masashi Hosokawa Kazuo Miyashita Hironori Negishi Junichi Ikuina Ryuji Noda Seiichi Shirasawa 《Journal of the American Oil Chemists' Society》2007,84(1):23-29
A high-performance liquid chromatographic (HPLC) method is described for the determination of conjugated linoleic acids (CLA)
and conjugated linolenic acids (CLN). Methyl esters prepared from purified lipid fractions of soybean oil were analyzed using
an HPLC system equipped with photodiode-array detector to detect peaks having maximum absorption around 233 and 275 nm. These
peaks were concentrated by AgNO3-silicic acid column chromatography and reversed-phase HPLC. The structural analysis, of dimethyloxazoline (DMOX) derivatized
methyl esters, using gas chromatography–mass spectrometry (GC–MS) showed the occurrence of 9,11- and 10,12-CLA and 8,10,13-,
8,10,12-, and 9,11,13-CLN. The comparison of these conjugated fatty acids with authentic isomers by HPLC revealed the presence
of isomeric mixtures of CLA [cis (c),trans(t) or t,c and t,t] and CLN (c,t,t or t,t,c and t,t,t). Traces of 9,11- and 10,12-CLA (c,t or t,c) were found in crude oil.
CLN isomers (8,10,12-18:3 and 9,11,13-18:3) were found to be forming during the bleaching phase of soybean oil processing.
8,10,13-CLN and 9,11- and 10,12-CLA (t,t) were only found in soybean oil after the deodorization step. CLN contents in commercial
soybean oil varied from 387 to 1,316 mg/kg oil. A decreased level of bleaching earth and temperature resulted in a reduced
CLN content. It is possible that CLN would be derived from the linoleate hydroperoxides formed during the processing and storage
of soybean oil. 相似文献