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排序方式: 共有228条查询结果,搜索用时 15 毫秒
61.
A Kinoshita R Shigemoto H Ohishi H van der Putten N Mizuno 《Canadian Metallurgical Quarterly》1998,393(3):332-352
The distributions of two alternative splicing variants of metabotropic glutamate receptor mGluR7, mGluR7a and mGluR7b, were examined immunohistochemically in the rat and mouse by using variant-specific antibodies raised against C-terminal portions of rat mGluR7a and human mGluR7b. Many regions throughout the central nervous system (CNS) showed mGluR7-like immunoreactivities (LI). The distribution patterns of mGluR7-LI in the rat were substantially the same as those in the mouse, although some species differences were observed in a few regions. Intense mGluR7a-LI was seen in the main and accessory olfactory bulbs, anterior olfactory nucleus, islands of Calleja, superficial layers of the olfactory tubercle, piriform cortex and entorhinal cortex, periamygdaloid cortex, amygdalohippocampal area, hippocampus, layer I of the neocortical regions, globus pallidus, superficial layers of the superior colliculus, locus coeruleus, and superficial layers of the medullary and spinal dorsal horns. The distribution of mGluR7b was more restricted. It was intense in the islands of Calleja, substantia innominata, hippocampus, ventral pallidum, and globus pallidus. The medial habenular nucleus also showed intense mGluR7a-LI in the rat but not in the mouse. For both mGluR7a- and mGluR7b-LI, localization in the active zones of presynaptic axon terminals was confirmed electron microscopically at synapses of both the asymmetrical and symmetrical types. It is noteworthy that mGluR7a-LI is seen preferentially in relay nuclei of the sensory pathways and that both mGluR7a- and mGluR7b-LI are observed not only in presumed glutamatergic axon terminals, but also in non-glutamatergic axon terminals including presumed inhibitory ones. Thus, mGluR7 may play roles not only as an autoreceptor in glutamatergic axon terminals, but also as a presynaptic heteroreceptor in non-glutamatergic axon terminals in various CNS regions. 相似文献
62.
Mamoru Mitomo Yoh-ichiro Sato Nobuo Ayuzawa Isamu Yashima 《Journal of the American Ceramic Society》1991,74(4):856-858
Plasma etching of β-Si3 N4 , α-sialon/β-Si3 N4 and α-sialon ceramics were performed with hydrogen glow plasma at 600°C for 10 h. The preferential etching of β-Si3 N4 grains was observed. The etching rate of α-sialon grains and of the grain-boundary glassy phase was distinctly lower than that of β-Si3 N4 grains. The size, shape, and distribution of β-Si3 N4 grains in the α-sialon/β-Si3 N4 composite ceramics were revealed by the present method. 相似文献
63.
Tomo Osawa Atsushi Sogabe Masayuki Shirao Shuji Nishihama Isamu Kaneda† Shin-ichi Yusa‡ 《International journal of cosmetic science》2009,31(6):479-479
IFSCC Magazines , 12 (2009) (1) 3–7
It is generally well known that the surface of an inorganic UV-protective powder used in a sunscreen formula is treated with a fatty acid or other hydrophobic chemicals to obtain a high water resistance. Due to the resulting strongly hydrophobic surface, the treatment has a clear drawback in that it allows the sunscreen to leave its base components on the skin after washing with regular soap. Therefore, in this study to develop an intelligent sunscreen formula that has a high water resistance and can be washed away easily with regular soap, we focused on a pH-responsive polymer as the surface-treatment agent for a UV-protective powder. Numerous experiments led to the synthesis of the 2-acrylamido-2-methyl-1-propanesulfonic acid/11-methacrylamidoundecanoic acid (AMPS/MAU) copolymer, which is hydrophobic in acidic to neutral solution and hydrophilic in basic solution. Titanium dioxide subjected to surface treatment was treated with the AMPS/MAU copolymer showed a high pH-responsiveness that was similar to that of the polymer. A W/O-type sunscreen containing the pH-responsive titanium dioxide showed a high water resistance as well as a high washability with regular soap.
Keywords: Detergent-washable, pH-responsive polymer, pH-responsive powder, sun care product, water-resistant 相似文献
It is generally well known that the surface of an inorganic UV-protective powder used in a sunscreen formula is treated with a fatty acid or other hydrophobic chemicals to obtain a high water resistance. Due to the resulting strongly hydrophobic surface, the treatment has a clear drawback in that it allows the sunscreen to leave its base components on the skin after washing with regular soap. Therefore, in this study to develop an intelligent sunscreen formula that has a high water resistance and can be washed away easily with regular soap, we focused on a pH-responsive polymer as the surface-treatment agent for a UV-protective powder. Numerous experiments led to the synthesis of the 2-acrylamido-2-methyl-1-propanesulfonic acid/11-methacrylamidoundecanoic acid (AMPS/MAU) copolymer, which is hydrophobic in acidic to neutral solution and hydrophilic in basic solution. Titanium dioxide subjected to surface treatment was treated with the AMPS/MAU copolymer showed a high pH-responsiveness that was similar to that of the polymer. A W/O-type sunscreen containing the pH-responsive titanium dioxide showed a high water resistance as well as a high washability with regular soap.
Keywords: Detergent-washable, pH-responsive polymer, pH-responsive powder, sun care product, water-resistant 相似文献
64.
Isamu Saito 《Water research》1984,18(3):319-323
The removal of iron cyano-complex ions [hexacyanoferrate(II) and (III) ions] in a dilute aqueous solution by activated carbon was investigated. The maximum adsorption of iron cyano-complex ions on activated carbon occurred at pH around 3. The hexacyanoferrate(III) ion was more adsorbable than the hexacyanoferrate(II) ion. Activated carbon promoted the oxidation of hexacyanoferrate(II) ion to (III) ion with dissolved oxygen in an acidic solution and the reduction of hexacyanoferrate(III) ion to (II) ion in an alkaline solution. The iron cyano-complex ion adsorbed on activated carbon could be eluted with higher concentrated acidic and alkaline solutions. The degree of elution decreased with an increase in potassium hydroxide concentration, since parts of the iron cyano-complexes on activated carbon were decomposed to form the iron hydroxide and the hexacyanoferrate(II) ion with an alkaline solution. The behavior of iron cyano-complexes in the presence of activated carbon, in the lower pH range (pH < 1) and at higher temperatures (80°C), was discussed. 相似文献
65.
Ouji Y Yoshida-Terakura A Hayashi Y Maeda I Kawase M Yamato E Miyazaki J Yagi K 《Journal of Bioscience and Bioengineering》2002,94(1):81-83
In search of an efficient nonviral vector, polyethyleneimine (PEI)-based vectors were examined. In general, the transfection efficiency of nonviral vectors is suppressed by serum. Here we show that PEI based vectors, particularly, the chitosan hexamer-PEI vector, could perform efficient gene transfection into intestinal epithelial cells (IEC-6) in the presence of serum. The conjugation order of the two polymers with a plasmid (first, chitosan hexamer; second, PEI) was found to be an important factor in enhancing transfection efficiency. 相似文献
66.
Toshitaka Idehara Kosuke Kosuga La Agusu Ryosuke Ikeda Isamu Ogawa Teruo Saito Yoh Matsuki Keisuke Ueda Toshimichi Fujiwara 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(7):775-790
A high frequency gyrotron with a 15 T superconducting magnet named Gyrotron FU CW VI has achieved continuous frequency tuning through the relatively wide range of 1.5 GHz near 400 GHz. The operation is at the fundamental cyclotron resonance of the TE06 cavity mode with many higher order axial modes. The output power measured at the end of the circular waveguide system ranges from 10 to 50 watts at the low acceleration voltage of 12 kV for beam electrons. The beam current is also low. It is around 250 mA. This gyrotron is designed as a demountable radiation source for the 600 MHz DNP-NMR spectroscopy. The design and operation results of the gyrotron FU CW VI are presented. 相似文献
67.
We performed a series of molecular dynamics (MD) simulations on Nafion® membranes containing various quantities of H2O and CH3OH. The simulations afforded diverse nanoscale phase-separated structures, such as clusters, channels, and cluster–channels. The calculated cluster–channel structure qualitatively agrees with the experimental results of X-ray diffraction studies. We also investigated the diffusion mechanisms for H2O, protons, CH3OH, H2, and O2 in these membranes. To reproduce the hopping transfer of protons, we employed a semi-classical MD approach using the empirical valence bond method. The estimated diffusion coefficients of H2O and proton in the membranes significantly depended on the H2O content, and these values showed qualitatively good agreement with the experimental results. The diffusion coefficient of proton in H2O-rich membranes was much larger than that of H2O, and the proton mainly formed H5O2+ complex. Furthermore, the simulation results indicate that the majority of CH3OH permeates through the H2O clusters, and the majority of H2 and O2 permeates through the hydrophobic region of the membrane. 相似文献
68.
Characterization of Na-X,Na-A,and coal fly ash zeolites and their amorphous precursors by IR,MAS NMR and XPS 总被引:7,自引:0,他引:7
By fusion with sodium hydroxide followed by a hydrothermal reaction, fly ash and Alenriched fly ash were converted into Na-X and Na-A zeolites, respectively. The authentic Na-X, Na-A and fly ash zeolites as well as their amorphous precursors have been characterized by IR, 29Si and 27Al MAS NMR, XPS/AES, TG, and comparative ion-exchange studies of Cs and K with Na in zeolite samples. It appears that the same structural unit with a terminal OH, such as a sodalite unit, was formed in the induction period of the hydrothermal reaction for Na-X and Na-A, and then cross-linked through D4R and D6R external linkages to build up the zeolite framework of Na-A and Na-X, respectively. 相似文献
69.
The nuisance species Limnoperna fortunei is a freshwater mussel whose infestations have harmed water intake facilities, such as water supply systems. We investigated the changes in the drift and the settlement of L. fortunei along a headrace channel. The densities of the drift and the settlement both decreased dramatically with the downstream distance from the L. fortunei source (a reservoir). In comparison with larval densities in the reservoir, drift densities decreased by 10 to 25% at 0.5 km downstream from the reservoir, and were less than 2% at sites more than 4.8 km downstream. Although larval densities at midnight (0:00-2:00) were approximately 1.5 times higher than those at noon (12:00-14:00) in a shallow layer (3 m depth) of the reservoir, we found no diurnal variation of drift densities in the headrace channel. Settlement densities at the site nearest the intake gate were much higher than those of the other sites further downstream in the headrace channel. The L. fortunei adult population in the channel could reduce drift individuals by attracting the larva. The attraction probably induces the massive aggregation at the location of the channel immediately below the drift source, resulting in biofouling. 相似文献
70.
Saburo Akiyama Nikako Tsukiji Isamu Akiba Minoru Inoue Yoshihisa Kano 《Polymer International》2001,50(6):659-662
The relationship between the surface composition and the rate of solvent evaporation (R) in blend films of poly(vinylidene fluoride‐co‐hexafluoroacetone) (P(VDF‐HFA)) and poly(2‐ethylhexyl acrylate‐co‐acrylic acid‐co‐vinyl acetate) (P(2EHA‐AA‐VAc)) has been investigated. P(VDF‐HFA), a low‐surface tension component, was concentrated on the surface when R was relatively high. In contrast, when R was relatively low, P(2EHA‐AA‐VAc), a low‐density component, was concentrated on the surface. Therefore, it is speculated that the factors dominating surface enrichment in polymer blends were changed from surface tension differences to density differences between the components when R was decreased. In addition, the affinity between components and substrate strongly affects the dominant factors determining the surface composition. © 2001 Society of Chemical Industry 相似文献