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31.
Kobayashi M Ohtsuka K Tamura Y Tomizawa S Kamijo K Iwakoshi K Kageyama Y Nagayama T Takano I 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2011,52(2):121-129
A survey of pesticide residues in 595 imported frozen products on the Tokyo market from April 1989 to March 2008 was carried out. Forty three kinds of pesticides, including organophosphorus, organochlorine, carbamate, pyrethroid and others, were detected between levels of trace (below 0.01 ppm) and 4.6 ppm from 162 samples. Chlorpyrifos, cypermethrin and omethoate were frequently detected in green vegetables (komatsuna leaf and spinach), cypermethrin and methamidophos were detected in pods and seeds (green soybean and string pea), chlorpropham (CIPC) was detected in potato, and captan and carbaryl were detected in berries (blueberry, raspberry and strawberry). The hydrophilic pesticide methamidophos was detected in flesh of lychee. Residue levels of these pesticides were calculated as between less than 0.5% and 30% of their ADI values according to the daily intake of frozen products. Therefore, these frozen products should be safe when they were eaten in customary amounts. 相似文献
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Yukari Totsuka Takashi Higuchi Toshio Imai Akiyoshi Nishikawa Takehiko Nohmi Tatsuya Kato Shuich Masuda Naohide Kinae Kyoko Hiyoshi Sayaka Ogo Masanobu Kawanishi Takashi Yagi Takamichi Ichinose Nobutaka Fukumori Masatoshi Watanabe Takashi Sugimura Keiji Wakabayashi 《Particle and fibre toxicology》2009,6(1):1-11
Background
Recently, manufactured nano/microparticles such as fullerenes (C60), carbon black (CB) and ceramic fiber are being widely used because of their desirable properties in industrial, medical and cosmetic fields. However, there are few data on these particles in mammalian mutagenesis and carcinogenesis. To examine genotoxic effects by C60, CB and kaolin, an in vitro micronuclei (MN) test was conducted with human lung cancer cell line, A549 cells. In addition, DNA damage and mutations were analyzed by in vivo assay systems using male C57BL/6J or gpt delta transgenic mice which were intratracheally instilled with single or multiple doses of 0.2 mg per animal of particles.Results
In in vitro genotoxic analysis, increased MN frequencies were observed in A549 cells treated with C60, CB and kaolin in a dose-dependent manner. These three nano/microparticles also induced DNA damage in the lungs of C57BL/6J mice measured by comet assay. Moreover, single or multiple instillations of C60 and kaolin, increased either or both of gpt and Spi- mutant frequencies in the lungs of gpt delta transgenic mice. Mutation spectra analysis showed transversions were predominant, and more than 60% of the base substitutions occurred at G:C base pairs in the gpt genes. The G:C to C:G transversion was commonly increased by these particle instillations.Conclusion
Manufactured nano/microparticles, CB, C60 and kaolin, were shown to be genotoxic in in vitro and in vivo assay systems. 相似文献36.
Kyoko Hori Masahiro Fukuta Hirokazu Shimooka Shigemi Kohiki Toetsu Shishido Masaoki Oku Masanori Mitome Yoshio Bando 《Journal of Alloys and Compounds》2005,390(1-2):261-264
β-Ga2O3 nanocolumns straightened and crossed perpendicularly each other were deposited on MgO (1 0 0) substrate by vapor phase transport method. Growth of the nanocolumns was examined at steps of 1000, 1050, and 1200 °C in elevation of source-boat temperature. We have drawn out the substrate from deposition-tube at each source-boat temperatures of 1000, 1050, and 1200 °C. Scanning electron microscopy of the sample with source-boat temperature of 1200 °C demonstrated that the straightened and elongated nanocolumns are crossing perpendicularly each other. Typical lengths of the nanocolumns were in the range of several hundreds nanometers below 1050 °C, and those of 1200 °C were in the range of ten to fifteen hundreds nanometers. Diameters of the nanocolumns stayed in the range of few hundreds nanometers, notwithstanding variation of the source temperature. X-ray diffraction and transmission electron microscopy with energy dispersive X-ray spectroscopy revealed that the nanocolumns are monoclinic β-Ga2O3 crystal, and the (4 0 0) plane of β-Ga2O3 nanocolumns is parallel to the (1 0 0) plane of MgO substrate. 相似文献
37.
Kawai T Chun WJ Asakura K Koike Y Nomura M Bando KK Ted Oyama S Sumiya H 《The Review of scientific instruments》2008,79(1):014101
The design and performance of a new high-pressure and high-temperature cell for measurement of x-ray absorption fine structure (XAFS) spectra of solid catalysts working in a flowing liquid are presented. The cell has flat, high-purity sintered cubic boron nitride (c-BN) windows which can tolerate high temperature (900 K) and high pressure (10 MPa). The c-BN is a new material which has the highest tensile strength, second only to diamond, and is also chemically and thermally stable. The use of the cell is demonstrated for measurements of PtPdAl(2)O(3) and Ni(2)PSiO(2) hydrodesulfurization catalysts at reaction conditions. A technique called delta chi (Deltachi), involving determining the difference between XAFS spectra of the sample at reaction conditions and the bare sample, is introduced. 相似文献
38.
Conventional verified methods for integration often rely on the verified bounding of analytically derived remainder formulas for popular integration rules. We show that using the approach of Taylor models, it is possible to devise new methods for verified integration of high order and in many variables. Different from conventional schemes, they do not require an a-priori derivation of analytical error bounds, but the rigorous bounds are calculated automatically in parallel to the computation of the integral.The performance of various schemes are compared for examples of up to order ten in up to eight variables. Computational expenses and tightness of the resulting bounds are compared with conventional methods. 相似文献
39.
Kyoko Shimizu Marie-Laure Abel Christopher Phanopoulos Servaas Holvoet John F. Watts 《Journal of Materials Science》2012,47(2):902-918
The interfacial interactions between a rigid polyurethane foam (RPUF) and aluminium have been studied to understand the mechanisms
of adhesion. Three different blowing systems are used in the production of the foam: chemical blowing, physical blowing and
a mix of chemical and physical blowing systems. In addition an unfoamed system has been examined for comparison of the catalysts
behaviour with and without blowing agents and the surfactant. Peeled failure surfaces have been examined by X-ray photoelectron
spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF–SIMS). To examine the intact interfacial regions
of the RPUFs cured against aluminium, samples have been sectioned by microtomy. The failure surfaces of the aluminium sides
exhibit relatively clean aluminium surfaces with RPUF residues observed for all three foamed systems; such thin RPUF layers
(ca. 1 nm) indicate good adhesion (and a cohesive failure) between foam and substrate and that the interfacial adhesion is
higher than the cohesive strength of the foam. The unfoamed system behaves in a similar manner but has a higher peel strength.
A fragment indicative of covalent bond formation between isocyanate and aluminium (nominal mass at 102 u: AlCHNO3
−) is observed on the failure surface of aluminium side, where RPUF/aluminium interface region is present, for all foams. The
catalyst used in these formulations, pentamethyldiethylenetriamine (PMDETA), is concentrated at the interface area. Whilst
examination of the sectioned specimens shows that the silicone surfactant is concentrated within the cell area fulfilling
its role on cell formation and stabilisation, and is not segregated at the RPUF/aluminium interface. 相似文献
40.
Aikawa K Murakami H Inomata K Maruyama T Fujisawa T Takahashi T Yamai S 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(3):178-184
Basal studies for the confirmation of sanitary rules in the kitchen were performed, focusing on preventing an outbreak of food poisoning due to eggs contaminated with Salmonella Enteritidis (SE), using hen and quail eggs. SE did not grow at 5 degrees C but grew markedly at 25 degrees C in eggs. The invasion and growth of SE were marked under very humid conditions regardless of whether the eggshell was damaged. The invasion of SE into egg also occurred when eggs were taken in and out of the refrigerator. Moreover, SE was spread immediately to all non-contaminated eggs when SE-contaminated eggs were cracked into a bowl with non-contaminated eggs. In homemade mayonnaise containing 15% vinegar, sterilization took several hours to occur. On a stainless-steel bowl, SE survived for 2 weeks or more. These findings suggest that it is necessary to pay attention to secondary contamination. 相似文献