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81.
T Tanaka S Komatsubara I Miyoshi S Hiraki S Tada 《Canadian Metallurgical Quarterly》1976,26(5):619-628
Non-African Burkitt's lymphoma is presented in a 29-year-old, unmarried woman, who developed tumors in both breats and ovaries, ascites and pleural effusion. Assessment of B cells in the tumor cells, derived from ascites, pleural effusion and tumor tissue is 90%, surface IgM being consisted of 86%, in an average. Histologically, the tumor tissue demonstrates prominent, socalled starry-sky effect, and cytologically, tumor cells are poorly-differentiated lymphocytoid cells in their feautures. 相似文献
82.
Phytochelatins (PCs) are heavy metal-binding peptides that play important roles in the detoxification of toxic heavy metals and the regulation of intracellular concentrations of essential metals in eukaryotes, including higher plants, fungi, and microalgae. Recently, PC synthase genes in higher plants and fission yeast have been identified and characterized, enabling molecular biological studies to unravel the mechanisms underlying PC synthesis. Moreover, recent routine database searches have unexpectedly identified genes that are similar to plant PC synthase genes in the genomes of worms and some prokaryotes. In this review, we introduce these recent advances in our understanding of the molecular mechanisms for PC biosynthesis and functions in order to supply basic information about the unique and attractive peptides applicable to various fields. 相似文献
83.
Ishihara K Matsunaga A Miyoshi T Nakamura K Nakayama T Ito S Koga H 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2005,46(2):33-39
Acrylamide (AAm) is formed from asparagine (Asn) and reducing sugar during cooking of foods at high temperature. We examined the formation of AAm in a model system using a glass fiber filter paper, and looked for suitable conditions for inhibiting AAm formation. In frying, the formation rate was about 10 times that in a moistureless oven. Increase of frying temperature and frying time increased AAm formation when the residual moisture was 5% or less. AAm increased with increasing amount of glucose (Glc) addition up to 1:1 with respect to Asn, but then decreased. On the other hand, in the case of fructose, as the amount added was increased, AAm increased accordingly. The AAm formation rate with respect to Asn increased when valine (Val) was co-present in a Glc and Asn reaction system. Cysteine and lysine inhibited the AAm formation rate. Pathways for the formation of AAm are proposed. 相似文献
84.
Y. Nakashima K. Yatsu K. Tsuchiya K. Ohtoshi M. Shoji N. Yamaguchi M. Ichimura M. Inutake T. Tamano S. Miyoshi 《Journal of Nuclear Materials》1993,200(3):351-354
A method for evaluating wall condition by using plasma impact desorption (PID) technique has been developed and successfully applied to the tandem mirror GAMMA 10 as a monitor for wall conditioning. A magnetically shielded quadrupole mass spectrometer was installed in the vacuum chamber of the GAMMA 10 central cell. The behaviour of the partial pressure of various gas molecules desorbed by ICRF-heated plasma discharges were analyzed. The predominant increase of the partial pressure due to PID (ΔPPID) was hydrogen (M = 2) and a small amount of impurity as CO (M = 28), CH3 (M = 15), H2O (M = 18) and CO2 (M = 44) was observed in the wall-conditioning discharges. The reduction of hydrogen pressure as well as ΔPPID of the above impurities was observed with the progress of wall conditioning. This behavior has a good correlation with the increase of partial pressures due to electron-impact desorption measured at the same period. The relation between ΔPPID and the charge-exchange flux was investigated. 相似文献
85.
The reaction of isobutene (IB) with its dimers (IB2) catalyzed by CF3SO3H yielded isobutene trimers (IB3) in high yield in nonpolar solvents at 0°C. The initial feed of isobutene, in the presence of equimolar IB2 or more, was selectively converted into IB3 without loss or accumulation of IB2. After complete consumption of the isobutene, however, the remaining IB2 rapidly dimerized to isobutene tetramers (IB4). 13C-NMR analysis of the products showed that the IB3 was formed via addition of the t-butyl cation (protonated isobutene to 2,4,4-trimethyl-1-pentene (an IB2 isomer); the trimer fraction was free from isomers arising from addition of the t-butyl cation to 2,4,4-trimethyl-2-pentene (another IB2 isomer) or addition of the IB2 cation to isobutene. The IB3 thus obtained was further oligomerized with CF3SO3H catalyst in nonpolar media in the range of 0 to ?25°C to give a mixture of IB5, IB6, and IB7 in high yield. With EtAlCl2 as catalyst, reaction of isobutene with IB2 and oligomerization of IB3 both resulted in products with a broad molecular weight distribution containing higher oligomers and complex hydrocarbons formed via cracking of the intermediate carbocations. 相似文献
86.
Timothy L. Kelly Yuri Yamada Celine Schneider Kazuhisa Yano Michael O. Wolf 《Advanced functional materials》2009,19(23):3737-3745
A new poly(p‐phenylenevinylene) (PPV) composite material has been developed by the incorporation of insoluble PPV polymer chains in the pores of monodisperse mesoporous silica spheres through an ion‐exchange and in situ polymerization method. The polymer distribution within the resultant colloidal particles is characterized by electron microscopy, energy dispersive X‐ray microanalysis, powder X‐ray diffraction, and nitrogen adsorption. It was found that the polymer was selectively incorporated into the mesopores of the silica host and was well distributed throughout the body of the particles. This confinement of the polymer influences the optical properties of the composite; these were examined by UV–vis and fluorescence spectroscopy and time‐correlated single‐photon counting. The results show a material that exhibits an extremely high fluorescence quantum yield (approaching 85%), and an improved resistance to oxidative photobleaching compared to PPV. These enhanced optical properties are further complemented by the overall processability of the colloidal material. In marked contrast to the insolubility of PPV, the material can be processed as a stable colloidal dispersion, and the individual composite spheres can be self‐assembled into opaline films using the vertical deposition method. The bandgap of the opal can be engineered to overlap with the emission band of the polymer, which has significant ramifications for lasing. 相似文献
87.
Yoshinobu Murakami Hiroki Kitani Jotaro Shirai Masayuki Nagao Norikazu Naito Kazuhisa Hatano Hirotoshi Kawamura 《Electrical Engineering in Japan》2012,180(3):9-17
This paper reports a study on the possibility of an aerial flashover between a coil conductor and a casing in rotating machines under the application of a lower voltage than Paschen's voltage, even when enough insulation distance is secured. The time lag to aerial flashover originating from surface flashover was measured. To understand the aerial flashover influenced by the parameters of the voltage application circuit, the aerial flashover distance was measured using a cable which had a simulated pore to confirm the above issue. The surface flashover characteristic was also measured using a photomultiplier tube (PMT). It became clear that aerial flashover occurred a few milliseconds after surface flashover generation. After showing the peak, the aerial flashover distance decreased with increasing time constant. The surface flashover time estimated by the PMT output exhibited different values with change of capacitance when the time constant is larger. On the other hand, the average surface flashover current was almost the same in spite of the change of capacitance. From these results, it was concluded that the aerial flashover distance was influenced by the time constant of the circuit. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(3): 9–17, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21295 相似文献
88.
Shin-ichi Miyoshi Naomi Okubo Satoko Mitsumori 《Journal of surfactants and detergents》2022,25(4):521-525
Linear alkylbenzene sulfonate (LAS) and polyoxyethylene lauryl ether (POLE) are the major surfactants in washing detergents. In the present study, we isolated surfactant-resistant bacteria from soil samples collected from a sports ground and a farm field. The samples were treated with 2.0% LAS or POLE at 25°C for 30 min and cultivated on agar plates at 25°C for several days, after which manifold bacterial colonies were isolated. Thereafter, we tested the ability of each bacterial isolate to resist the antibacterial activity of the surfactant. Ten LAS-resistant strains were isolated, and all were found to be Gram-negative bacteria such as Enterobacter and Pseudomonas. On the other hand, 18 POLE-resistant strains were isolated, of which 14 were Gram-positive bacteria including Bacillus and Microbacterium. Notably, one POLE-resistant strain was identified as Bacillus cereus, a potential causative agent for foodborne illness. The genera of LAS- and POLE-resistant bacteria did not overlap. Therefore, the combination of LAS and POLE could be more effective to eliminate soil bacteria from clothes and/or daily necessities. 相似文献
89.
Applicability of vacuum‐microwave drying for tomato fruit based on evaluations of energy cost,color, functional components,and sensory qualities
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90.