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91.
Maly Rose C.; Stein Judith A.; Umezawa Yoshiko; Leake Barbara; Anglin M. Douglas 《Canadian Metallurgical Quarterly》2008,27(6):728
Objectives: To examine racial/ethnic disparities in older women's health-related quality of life (QoL) and type of breast cancer treatment as mediated by physician-level and individual-level variables. Methods: A cross-sectional survey of a population-based, consecutive sample identified through the Los Angeles Cancer Surveillance Program of Latina (n = 99), African American (n = 66), and White (n = 92) women aged 55 years or older (N = 257) between 3 and 9 months after primary breast cancer diagnosis and at least 1 month posttreatment. An exploratory, empirically developed latent variable model tested the relationships among demographic and physician-related variables, patient attitudes, and health-related outcomes. Health-related outcomes included QoL measures and receipt of breast conserving surgery (BCS). Results: Latinas reported less BCS and poorer QoL compared with Whites. Physician communication that can empower patients, in terms of patient efficacy in patient?physician interactions and breast cancer knowledge, mitigated racial/ethnic disparities in receipt of BCS. Physician emotional support was not related to patient cognitive empowerment and treatment outcomes. Medical mistrust in minority women was related to less self-efficacy and less positive coping, as well as, both directly and indirectly, to reduced QoL. Latinas reported poorer QoL in the tested model. Conclusion: Physician communication style, specifically information giving and participatory decision making, may empower older women with breast cancer and help mitigate racial/ethnic disparities in surgical treatment received. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Akinori Saeki Shin-ichi Ohsaki Yoshiko Koizumi Shu Seki Seiichi Tagawa 《Synthetic Metals》2009,159(17-18):1800-1803
The charge carrier mobility in films of regioregular polythiophenes substituted by n-alkyl side-chains, of butyl, hexyl, octyl, decyl, and dodecyl, was investigated by flash-photolysis time-resolved microwave conductivity (FP-TRMC), and transient photoabsorption spectroscopy excited at 355 nm. The charge carrier concentration was estimated from inspecting radical anions of perylenecarboxydiimide (PDI), which also acts as an efficient electron acceptor to improve the yield of photocarrier generation. We discuss the dependence of side-chain length in terms of decay dynamics, quantum yield of charge carrier generation, and alternating current (ca. 9 GHz) mobility, which exceeded 0.12 cm2/(V s). 相似文献
93.
Ken Sugawara Kazuhide Yokota Jiro Takemoto Yoshiko Tanokura Tomoyuki Sekine 《Journal of Low Temperature Physics》1993,91(1-2):39-47
The zero-field critical temperature and the coherence length in the layered superconductor 2H-NbSe2−x
S
x
(x = 0–2.0) were investigated. The zero-field critical temperature decreases with increasing the residual resistivity. This
result can be explained in terms of the three-dimensional Anderson localization with the mobility edge below the Fermi level.
The coherence length as a function ofx can be explained by the theory of the anisotropic three-dimensional dirty superconductor. However it shows anomalous behavior
whenx = 0.6. This may be relevant to the change of the crystal structure or the disappearance of the CDW. The effective mass ratio
does not depend onx whenx ≤ 0.4. 相似文献
94.
Toshinobu Shigematsu Yoshiko Fujii Toyoichiro Shigi 《Journal of Low Temperature Physics》1997,108(1-2):87-102
The specific heat of copper potassium tutton salt has been measured down to 1 mK in order to investigate the hyperfine interaction
of this copper compound. The magnetic ordering of the electronic system occurs at 29.5 mK in zero field. Below the transition
temperature the electronic heat capacity decreases and the copper nuclear heat capacity of hyperfine splitting becomes dominant
in the heat capacity of the compound. The nuclear heat capacity has a broad peak around 3.5 mK. The entropy of copper nuclear
spin, which was calculated from the specific heat data, remains at 40% of ln(2I+1) at 1 mK. 相似文献
95.
Yoshiko Miyagawa Soji Miyagawa 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2002,190(1-4):256-260
In the surface analysis methods such as X-ray photoelectron spectroscopy, Auger electron spectroscopy, or secondary-ion mass spectroscopy, sputtering processes are used for depth profiling. However, ion beam bombardment changes the surface composition and the surface structure, which deteriorates the accuracy of the surface analysis and the depth resolution. We studied the preferential sputtering in some materials consisting of two components with different mass ratio by using the dynamic Monte Carlo simulation. Dose dependence of the depth profile of composition is presented. By Ar sputtering, the surface compositions of Au0.25Cu0.75, Au0.67Al0.33, and Ni0.5Cu0.5 alloys changed to Au0.28Cu0.72, Au0.76Al0.24, and Ni0.67Cu0.33, respectively. These results agreed with the experimental data. In order to compare the effect of mass ratio on the preferential sputtering, B–C, Si–C, and W–C systems were investigated. In B–C system, preferential sputtering by 1 and 3 keV Ar ion was negligible. In W–C system, a significant preferential sputtering occurred. In Si–C system, carbon was enriched in the outermost surface layer at a fluence lower than 3×1016 ions/cm2. At higher fluence, the partiality in concentration recovers because of the balance between the enrichment and the preferential sputtering. 相似文献
96.
Akiyama H Watanabe T Wakui C Chiba Y Shibuya M Goda Y Toyoda M 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(5):301-305
A detection method using the polymerase chain reaction (PCR) was developed to detect genetically modified (GM) potato (NewLeaf Y potato; NL-Y), of which the mandatory assessment has not yet been completed in Japan. The potato sucrose synthase gene was used as an internal control. We designed a primer pair to specifically detect NL-Y without false-positive results in processed potato foods infected with the potato virus Y (PVY). The DNA introduced into NL-Y using the primer pair could be detected from potato powder samples containing 0.05% NL-Y. In addition, we designed primer pairs for recognizing the CryIIIA gene to detect the NewLeaf potato (NL), NewLeaf Plus potato (NL-P) and NL-Y and for recognizing p-FMV in order to detect NL-P and NL-Y. The proposed method was applied to the detection of NL-Y in 26 processed potato foods and NL-Y was not detected in any samples. 相似文献
97.
Vinicius Romero Gonçales Elaine Yoshiko Matsubara José Maurício Rosolen Susana Inés Córdoba de Torresi 《Carbon》2011,49(9):3039-3047
A carbon micro/nanostructured composite based on cup-stacked carbon nanotubes (CSCNTs) grown onto a carbon felt has been found to be an efficient matrix for enzyme immobilization and chemical signal transduction. The obtained CSCNT/felt was modified with a copper hexacyanoferrate/polypyrrole (CuHCNFe/Ppy) hybrid mediator, and the resulting composite electrode was applied to H2O2 detection, achieving a sensitivity of 194 ± 15 μA mmol−1 L. The results showed that the CSCNT/felt matrix significantly increased the sensitivity of CuHCNFe/Ppy-based sensors compared to those prepared on a felt unrecovered by CSCNTs. Our data revealed that the improved sensitivity of the as-prepared CuHCNFe/Ppy–CSCNT/felt composite electrode can be attributed to the electronic interactions taking place among the CuHCNFe nanocrystals, Ppy layer and CSCNTs. In addition, the presence of CSCNTs also seemed to favor the dispersion of CuHCNFe nanocrystals over the Ppy matrix, even though the CSCNTs were buried under the conducting polymer layer. The CSCNT/felt matrix also enabled the preparation of a glucose biosensor whose sensitivity could be tuned as a function of the number of glucose oxidase (GOx) layers deposited through a Layer-by-Layer technique with an sensitivity of 11 ± 2 μA mmol−1 L achieved at 15 poly(diallyldimethylammoniumchloride)/GOx bilayers. 相似文献
98.
S.F. MahmudS.A. Pahlovy Yoshiko SatoIwao Miyamoto 《Diamond and Related Materials》2011,20(7):1056-1060
In this paper, we have studied the facet and ripple formation on a hemispherical diamond stylus by low energy (0.3-3.0 keV) oxygen ion beam bombardment at different ion incidence angle. The sputtered stylus was observed by SEM. From SEM image, we measured the ion incidence angle θmax where the etching rate is maximum and compared them with the theoretical values of θmax derived from Witcomb formula. From experimentally and theoretically obtained values of θmax, we measured the facet angles of the processed hemispherical diamond stylus. Our result shows increasing discrepancy between theoretical and experimental values of both θmax and facet angle towards lower ion energy (< 2 keV) due to dominance of chemical sputtering over physical sputtering. From our observation we found a diamond stylus can be sharpened at 3 keV ion energy if the original apex angle is > 70°. We also observed surface morphology of the processed hemispherical diamond stylus machined by 0.3-3 keV oxygen ion beam at different tilted conditions. Our observation confirms the formation of ripple on the processed diamond stylus at higher angles of ion incidence. The ripple orientation at ion incidence 40°-60° processed by 3 keV oxygen ion beam is in well agreement with the predictions of linear BH model. However, ripples were not observed at near normal incidence and grazing incidence in contrast to BH model. In order to avoid ripple formation, the diamond stylus needs to be processed within the region of low ion incidence angles. The smoothing region is broader in the low ion energy range but some etch pits are seen to form in this region due to chemical sputtering of the impurities present in the diamond stylus. 相似文献
99.
We studied the formation dynamics of low-molecular-weight organic semiconducting molecules of N,N′-bis[4-[bis(3-methylphenyl)amino]phenyl]-N,N′-diphenylbenzidine (DNTPD) during solvent evaporation. We dropped the DNTPD–toluene solution on a glass substrate and performed in situ measurements of mass, temperature, scattered light intensity, and photoluminescence (PL). We found that both light scattering and PL measurements were able to detect the onset of solid film formation from dissolved organic semiconducting materials. When a solid thin film forms during drying, sudden changes in scattered light and PL are observed. Furthermore, we also found that a period of time after the onset was necessary for completion of thin solid film formation. Observations and in situ PL measurement during thin-film formation by spin coating revealed that this period of time affected the optical properties of the film. This result indicates that quantitative information on the film formation process is quite important to obtain thin films with desired properties by coating and drying. Our in situ measurements were simple and practical approaches to monitor the formation dynamics of organic thin films during drying. 相似文献
100.
Watanabe M Yonezawa T Lee K Kumagai S Sugita-Konishi Y Goto K Hara-Kudo Y 《Journal of the science of food and agriculture》2011,91(13):2500-2504
BACKGROUND: Members of the genus Fusarium are well known as one of the most important plant pathogens causing food spoilage and loss worldwide. Moreover, they are associated with human and animal diseases through contaminated foods because they produce mycotoxins. To control fungal hazards of plants, animals and humans, there is a need for a rapid, easy and accurate identification system of Fusarium isolates with molecular methods. RESULTS: To specify genes appropriate for identifying isolates of various Fusarium species, we sequenced the 18S rRNA gene (rDNA), internal transcribed spacer region 1, 5.8S rDNA, 28S rDNA, β‐tubulin gene (β‐tub), and aminoadipate reductase gene (lys2), and subsequently calculated the nucleotide sequence homology with pair‐wise comparison of all tested strains and inferred the ratio of the nucleotide substitution rates of each gene. Inter‐species nucleotide sequence homology of β‐tub and lys2 ranged from 83.5 to 99.4% and 56.5 to 99.0%, respectively. The result indicated that sequence homologies of these genes against reference sequences in a database have a high possibility of identifying unknown Fusarium isolates when it is more than 99.0%, because these genes had no inter‐species pair‐wise combinations that had 100% homologies. Other markers often showed 100% homology in inter‐species pair‐wise combinations. The nucleotide substitution rate of lys2 was the highest among the six genes. CONCLUSION: The lys2 is the most appropriate genetic marker with high resolution for identifying isolates of the genus Fusarium among the six genes we examined in this study. Copyright © 2011 Society of Chemical Industry 相似文献