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81.
I Turkevych V Ryukhtin V Garamus S Kato T Takamasu G Kido M Kondo 《Nanotechnology》2012,23(32):325606
We performed studies of the self-organization processes in nanoporous alumina membranes at initial and late stages of aluminum anodization by using scanning electron microscopy (SEM) and small-angle neutron scattering (SANS). SEM observations indicated three stages in the self-organization of nanopores in alumina: (1) nucleation of random nanopores with a broad radius distribution, (2) narrowing the radius distribution and (3) slow evolution of the nanoporous structure towards ordering of nanopores into large domains. SANS studies revealed orientational correlation between ordered domains of nanopores, which is characterized by a small misorientation angle. For the samples with high aspect ratios of nanopores, the SANS patterns showed azimuthal smearing, which was attributed to the redistribution of nanopores between the domains during their growth. 相似文献
82.
For stroke-order free online multi-stroke character recognition, stroke-to-stroke correspondence search between an input pattern and a reference pattern plays an important role to deal with the stroke-order variation. Although various methods of stroke correspondence have been proposed, no comparative study for clarifying the relative superiority of those methods has been done before. In this paper, we firstly review the approaches for solving the stroke-order variation problem. Then, five representative methods of stroke correspondence proposed by different groups, including cube search (CS), bipartite weighted matching (BWM), individual correspondence decision (ICD), stable marriage (SM), and deviation-expansion model (DE), are experimentally compared, mainly in regard of recognition accuracy and efficiency. The experimental results on an online Kanji character dataset, showed that 99.17%, 99.17%, 96.37%, 98.54%, and 96.59% were attained by CS, BWM, ICD, SM, and DE, respectively as their recognition rates. Extensive discussions are made on their relative superiorities and practicalities. 相似文献
83.
Koki Ando Seiichi Yamamoto Keisuke Kurita Nobuo Suzui Yong-Gen Yin Satomi Ishii 《Journal of Nuclear Science and Technology》2017,54(9):933-939
Although a high-energy gamma camera can obtain images of 137Cs distribution by detecting the 662-keV gamma photons, its spatial resolution is reduced because high-energy gamma photons penetrate the edge of the pinhole collimator. To solve this problem, we developed a low-energy X-ray camera that detects the characteristic X-ray photons (32–37 keV) that are emitted from 137Cs to obtain high resolution images. We used a 45 × 45 × 1-mm-thick NaI(Tl) scintillator that was encapsulated in 0.1-mm-thick aluminum and optically coupled to a 2-inch square, position sensitive photomultiplier tube (Hamamatsu Photonics, PSPMT:H12700 MOD) as an imaging detector. The imaging detector was encased in a 2-cm-thick tungsten alloy container and a pinhole collimator was attached to its camera head. The spatial resolution and sensitivity were ~5 mm full-width at half-maximum and ~0.6 cps/MBq for the 1.5-mm pinhole collimator 10 cm from the collimator surface, respectively. We administered 5 MBq of 137Cs to a soybean seedling, imaged the distribution of radionuclides for six hours, and successfully obtained a high resolution image of it with our developed X-ray camera. We believe our camera will be a powerful tool for such 137Cs imaging in plants. 相似文献
84.
Yoshimasa Yamamoto Phan Trung Nghia Warunee Klinklai Takayuki Saito Seiichi Kawahara 《应用聚合物科学杂志》2008,107(4):2329-2332
The removal of proteins from natural rubber through a batch process was studied by the incubation of the rubber latex with urea in the presence of sodium dodecyl sulfate. Under suitable conditions, the total nitrogen content of deproteinized natural rubber (DPNR) decreased from 0.38 to 0.02 wt % after incubation for 10 min; this was similar to that of the rubber deproteinized with a proteolytic enzyme for 12 h. For applications, continuous incubation and centrifugation were individually investigated by the use of a semicircular channel and a continuous centrifuge, respectively, to scale up DPNR preparation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
85.
The effect of osmotic dehydrofreezing on the role of the cell membrane in carrot texture softening after freeze-thawing 总被引:1,自引:0,他引:1
Hiroko AndoKazuhito Kajiwara Seiichi OshitaToru Suzuki 《Journal of food engineering》2012,108(3):473-479
To understand the protective mechanism of the osmotic dehydrofreezing technique on carrot texture after freeze-thawing, two mechanical texture parameters, fracture stress related to the cell wall and initial modulus related to the cell membrane, as well as cell membrane water permeability using PFG-NMR were evaluated. In particular, to understand the role of the cell membrane in texture alteration, tissue in which the cell membrane was exposed to chloroform vapor was used. Although dehydrofreezing protected texture from freezing damage, the effect was only observed with respect to fracture stress, with exhibited values close to those for raw tissue. However, there was no protective effect on initial modulus and water permeability, in which values did not differ from those of cell membrane-free tissue. More specifically, osmotic dehydrofreezing had no effect on the cell membrane induced by freeze-thawing. 相似文献
86.
Watanabe Y Ichinomiya Y Shimada D Saika A Abe H Taguchi S Tsuge T 《Journal of Bioscience and Bioengineering》2012,113(3):286-292
A rapid and convenient method for the compositional analysis of polyhydroxyalkanoate (PHA) was developed using high-performance liquid chromatography (HPLC) and alkaline sample pretreatment in a 96-well plate format. The reliability of this system was confirmed by the fact that a mutant with a D171G mutation of Aeromonas caviae PHA synthase (PhaC(Ac)), which gained higher reactivity toward 3-hydroxyhexanoate (3HHx), was selected from the D171X mutant library. Together with D171G mutant, several single mutants showing high reactivity toward 3HHx were isolated by the HPLC assay. These new mutants and double mutants combined with an N149S mutation were used to synthesize P(3-hydroxybutyrate-co-3HHx) in Ralstonia eutropha PHB(-)4 from soybean oil as carbon source, achieving higher levels of 3HHx fraction than the wild-type enzyme. Based on these results, the high-throughput screening system will serve as a powerful tool for exploring new and beneficial mutations responsible for regulating copolymer composition of PHA. 相似文献
87.
Fumiya ShirakiTaeko Yoshikawa Akihiro Oshima Yuji OshimaYuya Takasawa Naoyuki FukutakeTomoko Gowa Oyama Tatsuya UrakawaHajime Fujita Tomohiro TakahashiToshitaka Oka Hisaaki KudoTakeshi Murakami Yoshimasa HamaMasakazu Washio 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(15):1777-1781
The graded energy deposition of heavy ion beam irradiation to polymeric materials was utilized to synthesize a novel proton exchange membrane (PEM) with the graded density of sulfonic acid groups toward the thickness direction. Stacked Poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) films were irradiated by Xe54+ ion beam with the energy of 6 MeV/u under a vacuum condition. The induced trapped radicals by the irradiation were measured by electron spin resonance (ESR) spectroscopy. Irradiated films were grafted with styrene monomer and then sulfonated. X-ray photo-electron spectroscopy (XPS) spectra showed that the densities of sulfonic acid groups were controlled for injection “Surface” and transmit “Back” sides of the fabricated PEM. The membrane electrode assembly (MEA) fabricated by the function-graded PEM showed improved fuel cell performance in terms of voltage stability. It was expected that the function-graded PEM could control the graded concentration of sulfonic acid groups in PEM. 相似文献
88.
Togashi T Yokoo N Umetsu M Ohara S Naka T Takami S Abe H Kumagai I Adschiri T 《Journal of Bioscience and Bioengineering》2011,111(2):140-145
Recently, a zinc oxide (ZnO)-binding peptide (ZnOBP) has been identified and has been used to assist the synthesis of unique crystalline ZnO particles. We analyzed the influence of ZnOBP on the crystal growth of ZnO structures formed from zinc hydroxide. The addition of ZnOBP in the hydrothermal synthesis of ZnO suppressed [0001] crystal growth in the ZnO particles, indicating that the specificity of the material-binding peptide for specific inorganic crystal faces controlled the crystal growth. Furthermore, the dipeptides with a partial sequence of ZnO-binding "hot spot" in ZnOBP were used to synthesize ZnO particles, and we found that the presence of these dipeptides more strictly suppressed (0001) growth in ZnO crystals than did the complete ZnOBP sequence. These results demonstrate the applicability of dipeptides selected from material-binding peptides to control inorganic crystal growth. 相似文献
89.
Seiichi Deguchi Toshinori Takeichi Shoji Shimasaki Muneaki Ogawa Norifumi Isu 《American Institute of Chemical Engineers》2011,57(8):2237-2243
To enhance photocatalytic water splitting, various oxidizing sacrifice agents (OSA) have been added to the system in order to scavenge the coproduced O2, and, thus, to hinder the reverse reactions. In the aim of achieving carbon‐neutral photocatalytic water splitting, nonfood hydrocarbons of castor‐ and jojoba‐oils were evaluated as OSA. Moreover, various surfactants were tested as emulsifiers for W/O binary solution for promoting photocatalytic water splitting rate. Among the OSA used, the castor‐oil was found to be more suitable candidate compared to jojoba‐oil, which was attributed to its smaller carbon chain numbers of mainly 18. Without surfactants, around 20 vol %‐castor‐oil aqueous binary solution with TiO2/Pt(0.10 wt %) provided the highest water splitting rate of about 30 mL‐H2/(m2·h). Among tested surfactants, liquid‐detergent was the best due to its optical transparency. 40 vol %‐ or 60 vol %‐castor‐oil emulsion with a drop of liquid‐detergent resulted in a water splitting rate of 125 mL‐H2/(m2·h), which was four times greater that the aforementioned highest value. © 2010 American Institute of Chemical Engineers AIChE J, 2011 相似文献
90.
Patjaree Suksawad Kenichiro Kosugi Yoshimasa Yamamoto Keiichi Akabori Hirofumi Kuroda Seiichi Kawahara 《应用聚合物科学杂志》2011,122(4):2403-2414
High‐proton‐conductive polymer electrolyte with a nanomatrix channel was prepared by graft copolymerization of styrene onto deproteinized natural rubber followed by sulfonation with chlorosulfonic acid. First, natural rubber latex was purified with urea in the presence of surfactant to remove almost all proteins present in the rubber. Second, graft copolymerization of styrene onto deproteinized natural rubber was carried out with tert‐butyl hydroperoxide/tetraethylenepentamine as an initiator at 30°C in latex stage. The graft‐copolymerized natural rubber (DPNR‐graft‐PS) was sulfonated with chlorosulfonic acid in chloroform solution at an ambient temperature. The resulting sulfonated DPNR‐graft‐PS was characterized by FTIR spectroscopy, solid state 13C CP/MAS NMR spectroscopy, elemental analysis, and transmission electron microscopy. High proton conductivity of about 0.1 S/cm, less water uptake of 24 wt % and comparatively good stress at break of 9 MPa were accomplished at suitable contents of styrene units and sulfur, i.e., 32 wt % and 75 mol %, respectively. The high proton conductivity, excellent stability, and good mechanical properties were associated with not only the formation of the nanomatrix channel but also a specific concentration of sulfuric acid group. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011. 相似文献