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A triglyceride of hydroxy fatty acids, lesquerella oil (LO), was structurally modified and used for the first time in the design, synthesis and evaluation of UV cured coatings. The results demonstrate that LO derivatives improved adhesion to metal substrates. For instance, methacrylated LO significantly improved adhesion to steel, and hydroxyethylmethacrylated LO improved adhesion to steel and aluminum substrates. The use of LO derivatives slightly lowered crosslink density and solvent resistance, and increased flexibility at the expense of Tg.  相似文献   
13.
Impedance spectroscopy has been shown to be a powerful tool to investigate the dielectric characteristics of powders suspended in suitable liquids. The electrical and dielectrical contributions of different components of the slurry can be extracted from the impedance spectra through measurement of frequency‐dependent relaxations. However, for ferroelectric powders that possess innate surface conductivity, such as BaTiO3, nanoparticles have sufficient conductivity to exclude low‐frequency fields that preclude impedance characterization of the particle core. In this work, the slurry technique is shown to be effective for dielectric characterization of not only micrometer‐sized particles through equivalent circuit modeling but also applicable to nanometer size dielectric particles upon remediating the conductive surface defect. Application of a self‐assembled monolayer (SAM) onto the nanoparticle as a surface passivation layer reduces the surface conductivity, stabilizes the nanoparticles to dissolution, and allows a reproducible measurement and modeling of the nanoparticle dielectric characteristics including nanoparticle permittivity. The dielectric permittivity of surface passivated, ~40 nm diameter barium titanate particles was measured to be εr ~ 135.  相似文献   
14.
It is now widely recognized that sulfur dioxide pollution of the atmosphere can no longer be tolerated. Thus, widespread attention has been given to removing sulfur from the fuels that we now burn. Solution of this problem is quite simple for natural gas; at the opposite extreme, for the case of coal, the problem has not yet been solved. This review describes efforts to desulfurize petroleum products, efforts which have been successful to a large extent but which have not achieved the degree of success ultimately required by society. As will be seen, such success presents a catalysis problem which is by no means simple and on which only evolutionary developments have been made to date. Here, then, is an excellent opportunity to exploit years of effort on catalytic theory in a way which will benefit mankind.  相似文献   
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A clarification.     
Claims that M. Rokeach and S. J. Ball-Rokeach (see record 1989-25677-001) noted an isolated trend in their research data on the ranking of equality in national samples and pulled 1 supporting indicator from research on changes in White racial attitudes (H. Schuman et al, 1985) without examining the larger body of evidence. Trend data and incomparable data sets contradict Rokeach and Ball-Rokeach's conclusions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
16.
In the Tri-State Leukemia Survey, the history of diseases in 605 adult male leukemia cases 15 years and older and in 668 adult male population controls was examined. These diseases occurred at least 1 year before leukemia was diagnosed. The data were based on respondents' answers that the disease was diagnosed by a physician; the respondent was either the subject or his spouse. Of 30 diseases studied, 7 showed an excess among the patients with leukemia: infectious hepatitis, eczema, psoriasis, diabetes, arthritis and rheumatism, heart disease, and ankylosing spondylitis. Mumps had a lower reported occurrence among the cases, whereas pneumonia was less frequent in acute lymphatic cases than in population controls. Three diseases occurred significantly less in controls than in persons with specific histologic types of leukemia. Our data revealed a more frequent history of herpes zoster (shingles) in chronic lymphatic leukemia, more hives in acute chronic myeloid cases, and meningitis in acute myeloid leukemia. When we only considered the patients' responses, more of them admitted having had acne than did our controls. The remaining diseases--childhood viral diseases, infectious mononucleosis, smallpox, typhoid fever, dysentery, scarlet fever, tuberculosis, asthma, hay fever, and goiter did not occur more frequently in cases than in controls. The findings were consistent with evidence from previous laboratory and clinical studies. The increased occurrence of infectious hepatitis in our case series is consistent with the findings of other studies showing an increased frequency of Australia antigen in patients with hepatitis, leukemia, and Down's syndrome.  相似文献   
17.
Computational procedures have recently been developed which accurately determine the excitation (including mutual coupling effects) at each element of a closely spaced array enabling it to perform in some desired manner. A procedure for designing a transmission-line feed network capable of realizing these required excitations is described. The result is a narrow-band feed system composed simply of a transmission line together with a small number of stubs. A comparison between theoretical and experimental results is given.  相似文献   
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The chromosomal inducible Tcr determinant from Proteus mirabilis was cloned and the nucleotide sequence of both the structural and repressor genes determined. The deduced amino acid sequence of the structural protein shows the highest similarity to TetA(H) from Pasteurella multocida (78.4%), followed by TetA(B) from Tn10 (50.9%). Based on this analysis, we suggest that this new determinant can be assigned to a new class, TetJ.  相似文献   
20.
Moisture in polymerization of a cationically cured silicone epoxy monomer blend is an important parameter that affects the resulting polymer properties. We report the kinetics of the cationic polymerization of epoxy monomers as a function of water concentration, directly quantified using Karl Fischer (KF) titration that was characterized using Fourier transform infrared (FTIR) spectroscopy and also the mechanical strength of resulting polymers via diametral tensile strength measurements. Methodology and results for a silicone epoxy monomer material were compared with the same methodology applied to a “control” monomer, 3,4‐epoxycyclohexylmethyl 3,4‐epoxycyclohexyane carboxylate, for which moisture effects have been previously studied. Initially, an increase in moisture during cationic polymerization of epoxy caused increased rate (ROC) and degree of conversion (DOC) that for the silicone epoxy was followed by decreased DOCs for water contents approaching saturation, i.e., [H2O]∼0.19 wt %. Further, the rate of conversion was also affected by the presence of moisture with a trend analogous to the DOC. Diametral tensile strength measurements found that small amounts of water present during polymerization caused small changes in tensile strength but found polymer strengths to be significantly decreased if initial water concentrations approached saturation or were in excess of saturation. Lower strengths corresponded with reduced rates of conversion and DOCs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41831.  相似文献   
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