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101.
Takahito Itoh Takahiro Sakakibara Masashi Tamura Masataka Kubo 《Electrochimica acta》2010,55(4):1419-1424
The hyperbranched polymers (HBP-SA-Acs) with both a sulfonic acid group as a functional group and an acryloyl group as a cross-linker at terminals in different ratios of sulfonic acid group/acryloyl group (SO3H/Ac) were successfully synthesized as a new thermally stable proton-conducting electrolyte. The cross-linked hyperbranched polymer electrolyte membranes (CL-HBP-SAs) were prepared by thermal polymerizations of the HBP-SA-Acs using benzoyl peroxide, and their ionic conductivities under dry condition and thermal properties were investigated. The ionic conductivities of the CL-HBP-SAs were found to be in the range of 2.2 × 10−4 to 3.3 × 10−6 S/cm, depending upon the SO3H unit contents, at 150 °C under dry condition, and showed the Vogel-Tamman-Fulcher (VTF) type temperature dependence, indicating that proton transfer is cooperated by local polymer chain motion. All CL-HBP-SAs were thermally stable up to 260 °C, and they had suitable thermal stability as electrolyte membranes for the high-temperature fuel cells under dry condition. Fuel cell measurement using a single membrane electrode assembly cell with a cross-linked electrolyte membrane was successfully performed under non-humidified condition. It was demonstrated that applying the concept of dry polymer system to proton conduction is one possible approach toward high-temperature fuel cells. 相似文献
102.
Y. Morisada T. Nagaoka M. Fukusumi Y. Kashiwagi M. Yamamoto M. Nakamoto 《Journal of Electronic Materials》2010,39(8):1283-1288
A low-temperature bonding process to form joints with high strength and ionic migration resistance using mixed Cu–Ag nanoparticles
was studied. Although it was difficult to obtain strong joints using Cu nanoparticles, with the addition of Ag nanoparticles
to the Cu nanoparticles the bonding strength of the Cu-to-Cu joints increased. The joints formed by the mixed Cu–Ag nanoparticles
at 350°C exhibited a high bonding strength of ~50 MPa. Counterelectrodes made of the mixed Cu–Ag nanoparticles had four times
higher ionic migration resistance compared with counterelectrodes made only of Ag nanoparticles. 相似文献
103.
Shinya Higashimoto Kohei Okada Tomoki Morisugi Masashi Azuma Hiroyoshi Ohue Tae-Ho Kim Masaya Matsuoka Masakazu Anpo 《Topics in Catalysis》2010,53(7-10):578-583
The photocatalytic oxidation of benzyl alcohol into benzaldehyde proceeded with high conversion and selectivity on a TiO2 photocatalyst by O2 under visible light irradiation. Surface complex formed by the interaction of benzyl alcohol with the Ti sites and/or surface OH groups of TiO2 play an important role in the absorption of visible light and unique selective photocatalytic reaction. 相似文献
104.
Yasuda K Nakamoto T Yasuhara M Okada H Nakajima T Kanzaki H Hori M Ozaki H 《Reproduction (Cambridge, England)》2007,133(4):797-806
To assess the role of protein kinase Cbeta (PKCbeta) in human myometrial contractions during pregnancy, we evaluated the effect of a PKCbeta inhibitor (LY333531) on the pregnant and nonpregnant myometrial contractions and compared the level of PKCbeta in the pregnant myometrium with that in the nonpregnant myometrium. The effects of LY333531 on the myometrial contractions were examined by measuring contractile activity (frequency and amplitude). PKCbeta in human myometrium was assessed at mRNA level using real-time PCR method. The characteristics of contractile activity were different between the pregnant and the nonpregnant myometrium. The amplitude of rhythmic contractions in the preterm and term myometrium was increased 2- to 2.5-fold when compared with that in the nonpregnant myometrium, but the frequency of rhythmic contractions was decreased by about half. LY333531 (10(-6) M) reduced the increased amplitude in the preterm and term myometrium by about 50%, and the inhibitory effects of LY333531 in the pregnant myometrium were significantly greater than that in the nonpregnant myometrium (about 50 vs 25%). However, the frequency in the pregnant and nonpregnant myometrium was not influenced by LY333531. Real-time PCR revealed a significant, five- to sevenfold increase in the expression of PKCbeta mRNA in the preterm and term myometrium when compared with the nonpregnant myometrium. These findings suggest that the increased amplitude of human myometrial contractions during pregnancy is related to the increased level of PKCbeta. A PKCbeta inhibitor may reduce preterm uterine contractions and prevent preterm delivery. 相似文献
105.
Yamamoto T Mukai K Yamashita H Kubota M Fukuda S Kurimoto M Tsujisaka Y 《Journal of Bioscience and Bioengineering》2005,100(2):212-215
Random mutation by error-prone PCR was introduced into kojibiose phosphorylase from Thermoanaerobacter brockii ATCC35047. One thermostable mutant enzyme, D513N, was isolated. The D513N mutant enzyme showed an optimum temperature of 67.5-70 degrees C (the wild type, 65 degrees C), and thermostability up to 67.5 degrees C (the wild type, up to 60 degrees C). The half-lives of D513N were estimated to be 135 h at 60 degrees C, 110 min at 70 degrees C and 6 min at 75 degrees C, respectively. They were about 1.6-fold, 7-fold and 6-fold longer than those of the wild-type enzyme, respectively. 相似文献
106.
Shimizu M Miyashita K Kitagaki H Ito K Shimoi H 《Journal of Bioscience and Bioengineering》2005,100(6):678-680
Sake yeasts are used for sake brewing and have a crucial role in the quality of sake, since they produce not only ethanol but also various compounds that provide sake flavors. Therefore, the appropriate selection and monitoring of a strain used in sake mash is important. However, the identification of specific sake yeast strains has been difficult, because sake yeasts have similar characteristics in taxonomic and physiological analyses. We found amplified fragment length polymorphisms (AFLPs) in the PCR products of the AWA1 gene of sake yeast strains. The AWA1 gene encodes a cell wall protein that is responsible for foam formation in sake mash. This polymorphism of the AWA1 gene can be used for the identification of sake yeast strains. 相似文献
107.
108.
Masashi Ohno Fumiakira Mori Yasuhiro Minamikawa R. M. Thushara Damayanthi Hiroyuki Takahashi Hiromi Sato Hidenori Toyokawa 《Journal of Low Temperature Physics》2008,151(1-2):229-233
To realize new TES imaging for high energy X-ray or gamma-ray spectrometer with a large pixel array and high count rate, we
will try to develop a new radiation absorber self-adjusting the operating temperature and adopting an original reading out
method of large pixel array using parallel biasing scheme. Our first prototype TES pixel using Au/Ti/Au tri-layer which consists
of the small heat sensors and the radiation absorption area, and these are biased in serial. In this device, the current pulse
with the decay time constant of less than 20 microseconds of incident X-rays from 55Fe source were observed.
相似文献
109.
Mizuki Tsuta Yasuhiko Sasaki Ikuo Takeuchi Hideki Nakamoto Jun Ishikawa Susumu Kawasaki Junichi Sugiyama Kaori Fujita Masatoshi Yoshimura Mario Shibata Mito Kokawa 《LWT》2014
Flow cytometry (FCM) and aerobic plate count (APC) by the culture method were performed on green tea samples spiked with Escherichia coli type strain NCTC9001 (ATCC11775) solutions of different concentrations. In FCM, fluorescence signals from multiple stained bacteria and other fluorophores are detected using detector channels, and recorded as events with a voltage at each channel. FCM data were analyzed in two ways: conventional and multivariate analysis. In the former, the number of events with voltages larger than the defined threshold values was regarded as the predicted APC. In the latter, voltage histograms of all channels were obtained and merged horizontally to serve as explanatory variables. Then a partial least squares regression (PLSR) model was built to predict APC from the histogram data. The coefficient of determination (R2) and the root mean square error (RMSE) between APC by the culture method and that predicted by conventional FCM were 0.916 and 1.08 cfu/ml2. The APC values predicted by the PLSR model and those measured were in good agreement with R2 of 0.982 and RMSE of 0.417 cfu/ml, which verified the potential of the proposed method for improving APC prediction accuracy by FCM. 相似文献
110.