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131.
A series of new amphoteric surfactants, having a quaternary ammonium group and a phosphoric acid group, 2-(N-alkyl-N,N-dimethylammonio)ethyl
hydrogen phosphates (alkyl: dodecyl, tetradecyl, hexadecyl), were prepared by introducing a phosphoric acid group into N-alkyl-N,N-dimethyl-(N-2-hydroxyethyl)
ammoniumiodide, followed by neutralization with sodium hydroxide and removal of inorganic salts. By the evaluation of the
physicochemical properties, it was found that the phosphobetaines behave like “nonionic” surfactant in the zwitterionic region,
having very small CMC values in comparison with sodium 2-(N-alkyl-N-methylamino)ethyl hydrogen phosphates. Additionally, similar
trends were also observed in the experiments from the point of the effect of electrolyte and temperature on CMC, respectively.
It should be considered that the hydrophobicity of the surfactant molecule is increased by the electronic interaction between
the quaternary ammonium group and a phosphoric acid group. On the other hand, the phosphobetaines gave the smaller values
of the occupied area per molecule at the air/water interface than sodium 2-(N-alkyl-N-methylamino)ethyl hydrogen phosphates.
Therefore, it is clear that the phosphobetaines have higher surface-active properties than the amphoteric surfactants. 相似文献
132.
Satoshi Sakoda Noriko Nakao Ikuya Watanabe 《Journal of materials science. Materials in medicine》2018,29(3):34
The aim was to investigate the effect of machining instruments on machinability of dental ceramics. Four dental ceramics, including two zirconia ceramics were machined by three types (SiC, diamond vitrified, and diamond sintered) of wheels with a hand-piece engine and two types (diamond and carbide) of burs with a high-speed air turbine. The machining conditions used were abrading speeds of 10,000 and 15,000?r.p.m. with abrading force of 100?gf for the hand-piece engine, and a pressure of 200?kPa and a cutting force of 80?gf for the air-turbine hand-piece. The machinability efficiency was evaluated by volume losses after machining the ceramics. A high-abrading speed had high-abrading efficiency (high-volume loss) compared to low-abrading speed in all abrading instruments used. The diamond vitrified wheels demonstrated higher volume loss for two zirconia ceramics than those of SiC and diamond sintered wheels. When the high-speed air-turbine instruments were used, the diamond points showed higher volume losses compared to the carbide burs for one ceramic and two zirconia ceramics with high-mechanical properties. The results of this study indicated that the machinability of dental ceramics depends on the mechanical and physical properties of dental ceramics and machining instruments. 相似文献
133.
134.
High‐resolution OLED display with remarkably low power consumption using blue/yellow tandem structure and RGBY subpixels 下载免费PDF全文
Ryohei Yamaoka Toshiki Sasaki Riho Kataishi Noriko Miyairi Koji Kusunoki Makoto Kaneyasu Hiroyuki Miyake Nobuharu Ohsawa Satoshi Seo Yoshiharu Hirakata Shunpei Yamazaki Koji Ono Takayuki Cho Hidenori Mori 《Journal of the Society for Information Display》2015,23(10):451-456
A top‐emission organic light‐emitting diode (OLED) with a microcavity structure combined with a blue/yellow tandem structure was developed. A high‐resolution active‐matrix OLED display with the world's lowest level of power consumption using the tandem OLED with red, green, blue, and yellow subpixels was fabricated. 相似文献
135.
Shiro Urano Midori Hoshi-Hashizume Noriko Tochigi Mitsuyoshi Matsuo Masataka Shiraki Hideki Ito 《Lipids》1991,26(1):58-61
A remarkable increase in the permeability of erythrocyte ghosts and liposomal membranes composed of erythrocyte lipids from
aged diabetics was revealed by measuring [14C]glucose leakage. There were no significant differences in the contents of free cholesterol or phospholipids, or in the cholesterol/phospholipid
ratio between diabetic and normal erythrocyte membranes, but significantly higher amounts of unsaturated fatty acids, arachidonic
acid and docosahexaenoic acid were observed in the erythrocyte membranes of diabetics. Reconstituted liposomes prepared from
aged diabetic erythrocyte lipids were highly susceptible to superoxide-induced oxidative stress. Vitamin E was highly effective
in suppressing the peroxidative lysis of liposomes composed of diabetic erythrocyte lipids. The effect of superoxide dismutase
(SOD) on the inhibition of peroxidation of unsaturated lipids within liposomal membranes was less than that of vitamin E. 相似文献
136.
We investigated the influence of various substrates on the uptake of long-chain fatty acid into IEC-6, rat intestinal epithelial
cell line. The uptake of [3H]oleic acid into IEC-6 cells was a saturable function of the oleic acid concentration. Long-chain fatty acids significantly
inhibited the oleic acid uptake into IEC-6 cells and shorter-chain fatty acids had little or no effect. Various fatty acid
esters suppressed the oleic acid uptake into IEC-6. Fatty alcohols also inhibited oleic acid uptake into IEC-6 and the length
of the carbon chain played an important role. These results suggest that long-chain fatty acid uptake was inhibited by the
substrates which had a structure similar to long-chain fatty acids, especially those with a long carbon chain. At least two
molecules, fatty acid translocase and fatty acid transport protein type 4, which are considered to be involved in the long-chain
fatty acid transport into the cell, were expressed on IEC-6 cells, supporting the existence of the carrier-mediated system
of long-chain fatty acid transport on IEC-6 cells. 相似文献
137.
Waichiro Tsuji Tokie Nakao Kyoko Ohigashi Kinuyo Maegawa Noriko Kobayashi Satomi Shukri Sadako Kasai Kyoko Miyanaga 《应用聚合物科学杂志》1986,32(5):5175-5192
By impregnating cotton fiber with alkaline swelling agents and reacting with some chemical agents which can be substituted for the hydroxyl groups on cellulose molecules in the presence of alkali, highly accessible or decrystallized cotton fibers can be obtained. As the effective substitution reactions, acetylation by acetic anhydride and cyanoethylation by acrylonitrile were applied. The cotton fibers modified by these chemical treatments showed no decrease of tensile strength, and had moisture regain higher than the untreated cotton though the degrees of substitution were as high as 20–30 mol %. The resistance to heat or acid and the soil removal were improved. Dyeability for direct dye was increased, and dyeability for disperse or cationic dye was also given. Benzoylation and oleoylation were also investigated. Crease recovery of the cotton fabrics was somewhat improved and dyeability for disperse dye was given. The cotton fabrics oleoylated after decrystallizing by alkali–acrylonitrile treatment had moisture regain almost the same as the untreated cotton, while high water repellency was given. 相似文献
138.
Toshie Kanayasu Ikuo Morita Junko Nakao-Hayashi Noriko Asuwa Chiho Fujisawa Toshiharu Ishii Hideki Ito Sei-itsu Murota 《Lipids》1991,26(4):271-276
We previously have described a quantitative angiogenesisin vitro model, in which endothelial cells are cultured between two layers of type I collagen gel and become organized into tube-like
structures. Using this model, the effect of eicosapentaenoic acid (20∶5n−3) on tube formation was investigated. When the endothelial
cells isolated from bovine carotid artery were treated for 2 days with 5 μg/mL of arachidonic acid (20∶4n−6), eicosapentaenoic
acid or docosahexaenoic acid (22∶6n−3), these polyunsaturated fatty acids were extensively incorporated into cellular phospholipids.
The content of arachidonic, eicosapentaenoic and docosahexaenoic acid increased from 9.58% to 23.29%, from 0.98% to 11.76%
and from 6.88% to 18.40%, respectively. When the eicosapentaenoic acid-treated cells were cultured between collagen gels,
the tube-forming ability of the cells was markedly inhibited. The inhibition was dose-dependent between 1.0 and 5.0 μg/mL
of eicosapentaenoic acid. At 5.0 μg/mL of eicosapentaenoic acid the inhibition reached 76%. By contrast, arachidonic acid
increased tube formation, and docosahexaenoic acid had no effect. To elucidate the mechanism of eicosapentaenoic acid induced
inhibition ofin vitro tube formation, we examined the effect of the acid on the proliferation of endothelial cells. Eicosapentaenoic acid at any
dose (<5.0 μg/mL) had no effect on the proliferation of endothelial cells cultured on plastic plates without collagen gel.
However, when the cells were cultured between collagen gels, eicosapentaenoic acid inhibited cell growth in a dose-dependent
manner with maximum inhibition being observed at 2.5 μg/mL. These data suggest that eicosapentaenoic acid suppresses tube
formation of endothelial cells, at least in part,via its inhibitory effect on cellular proliferation. Thus eicosapentaenoic acid may act as an endogenous inhibitor of angiogenesis
under various pathological conditions, including tumor growth and chronic inflammation. 相似文献
139.
140.
Hong-Tao Sun Minoru Fujii Noriko Nitta Minoru Mizuhata Hidehiro Yasuda Shigehito Deki Shinji Hayashi 《Journal of the American Ceramic Society》2009,92(4):962-966
Nickel-doped forsterite (Ni2+ :Mg2 SiO4 ) nanocrystals have been synthesized by a facile molten-salt approach in the presence of NaCl and a surfactant (NP-7.5). The products were characterized by X-ray diffraction, transmission electron microscopy (TEM), high-resolution TEM, selected area electron diffraction (SAED), and luminescence spectra measurements. The crystal size could be controlled by tailoring the synthesis parameters. TEM, high-resolution TEM, and SAED results revealed the single crystalline character of Mg2 SiO4 nanoparticles. A possible model for the growth of Ni2+ :Mg2 SiO4 nanocrystals was postulated. The obtained Ni2+ :Mg2 SiO4 nanocrystals show strong, super broad, near-infrared luminescence at room temperature. These doped Mg2 SiO4 nanocrystals are promising gain mediums for super broadband optical amplification. 相似文献