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231.
This paper proposes a visualization method of news distribution in Blog space. Recently, Blog is becoming one of the important
information resources on the Web, from which trend information can be obtained. On the other hand, online news site is another
information resource, which reports latest events in the world. This paper focuses on the combination of both resources, and
proposes a method for visualizing news distribution in Blog space, which indicates various access patterns to news articles
in Blog space. The types of objects that are to be visualized as well as their relationships are defined, based on which interactive
information visualization system is proposed. Experiments with test subjects are performed to investigate the viewpoints they
employ for examining news distribution in Blog space. The results show that test subjects can examine news distribution in
Blog space from various viewpoints, which affects their estimation of the impacts of news articles.
相似文献
Yasufumi TakamaEmail: |
232.
N. Ogata T. Tanaka T. Ogihara K. Yoshida Y. Kondou K. Hayashi N. Yoshida 《应用聚合物科学杂志》1993,48(3):383-391
Blending of polystyrenes (PS) with a thermotropic liquid crystalline polymer (LCP) was performed by using a continuous corotating twin screw extruder. The influence of LCP content on the blending process was studied by changing the barrel heater temperature and the screw speed. The torque of screw shafts, generated during the blending process, was influenced by LCP content and its influence was not simple. The torque generated during the blending process was not directly related to the apparent melt viscosity of blends. Further, the effects of the matrix viscosity on the morphology and mechanical properties of the PS/LCP blends were studied using three grades of PS as matrix resins. It was found that the size of the LCP dispersed phase decreased with increasing matrix viscosity. Consequently, the mechanical properties of the PS/LCP blend were improved. © 1993 John Wiley & Sons, Inc. 相似文献
233.
Hydrogenation of 1,3-butadiene and of crotonaldehyde over highly dispersed Au catalysts 总被引:4,自引:0,他引:4
When Au is deposited as nano-particles on select metal oxides, it exhibits surprisingly high catalytic activity for many oxidation reactions. Therefore, there is also the possibility to improve the activities of Au catalysts for hydrogenation using the appropriate preparation methods like the gas-phase grafting method (GG) and the deposition precipitation method (DP). In this work, we investigated the hydrogenation of 1,3-butadiene and of crotonaldehyde over Au catalysts prepared by GG and DP and discussed the structure sensitivity of these reactions. From these experiments, it was found that the catalytic activities for the hydrogenation of 1,3-butadiene over Au catalysts was almost structure insensitive in terms of the size effect of Au particles and the influence of metal oxides supports and the crotonaldehyde hydrogenation over Au catalysts was slightly sensitive to the selection of the support in the view point of the product selectivity. 相似文献
234.
Fine particles ofphotocatalytic anatase TiO2 prepared through hydrolysis of titanium tetraisopropoxide were coated by carbon. A reduced phase, Ti4O7, was formed through interaction between TiO2 and the coating carbon. EXAFS analysis on this Ti4O7 phase showed an intermediate Ti-Ti distance between those in anatase and rutile, which agreed with the structure composed of two-dimensional slabs of Ti-O octahedra separated by a shear plane. This carbon-coated Ti4O7 was confirmed to have photocatalytic activity, even though a little lower than anatase, examining the decomposition of methylene blue in water under LTV irradiation. 相似文献
235.
Biotransporting Self‐Assembled Nanofactories Using Polymer Vesicles with Molecular Permeability for Enzyme Prodrug Cancer Therapy
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Tomoki Nishimura Yoshihiro Sasaki Kazunari Akiyoshi 《Advanced materials (Deerfield Beach, Fla.)》2017,29(36)
As “biotransporting nanofactories”, in vivo therapeutic biocatalyst nanoreactors would enable encapsulated enzymes to transform inert prodrugs or neutralize toxic compounds at target disease sites. This would offer outstanding potential for next‐generation therapeutic platforms, such as enzyme prodrug therapy. Designing such advanced materials has, however, proven challenging. Here, it is shown that self‐assembled nanofactories formulate with polymeric vesicles with an intrinsically permeable membrane. The vesicles, CAPsomes, are composed of carbohydrate‐b‐poly(propylene glycol) and show molecular‐weight‐depended permeability. This property enables CAPsomes to act as biocatalyst nanoreactors, protecting encapsulated enzymes from degradation while acting on low‐molecular‐weight substrates. In tumor bearing mice, combined treatment with enzyme‐loaded CAPsomes and doxorubicin prodrug inhibit tumor growth in these mice without any observable toxicity. The results demonstrate, for the first time, in vivo therapeutic efficacy of CAPsomes as nanofactories for enzyme prodrug cancer therapy. 相似文献
236.
Sedimentation pinched-flow fractionation for size- and density-based particle sorting in microchannels 总被引:1,自引:1,他引:0
Tomoki Morijiri Satoshi Sunahiro Masashi Senaha Masumi Yamada Minoru Seki 《Microfluidics and nanofluidics》2011,11(1):105-110
A simple and efficient device for density-based particle sorting is in high demand for the purification of specific cells, bacterium, or environmental particles for medical, biochemical, and industrial applications. Here we present microfluidic systems to achieve size- and density-based particle separation by adopting the sedimentation effect for a size-based particle sorting technique utilizing microscale hydrodynamics, called ??pinched-flow fractionation (PFF).?? Two schemes are presented: (a) the particle inertia scheme, which utilizes the inertial force of particle movement induced by the momentum change in the curved microchannel, and (b) the device rotation scheme, in which rotation of the microdevice exerts centrifugal force on the flowing particles. In the experiments, we successfully demonstrated continuous sorting of microparticles according to size and density by using these two schemes, and showed that the observed particle movements were in good agreement with the theoretical estimations. The presented schemes could potentially become one of the functional components for integrated bioanalysis systems that can manipulate/separate small amount of precious biological samples. 相似文献
237.
Takeshi A. Yamamoto Takayuki Kondou Yasuhiro Kodera Takashi Ishii Manshi Ohyanagi Zuhair A. Munir 《Journal of Materials Engineering and Performance》2005,14(4):460-466
The consolidation of SiC nanopowder synthesized by the mechanical alloying method was subsequently accomplished by spark plasma
sintering of 1700 °C for 10 min under an applied pressure of 40 MPa. The SiC sintered compact with relative density of 98%
consisted of nano-sized particles smaller than 100 nm. This phenomenon resulted in the ordering process of stacking disordered
structure formed by mechanical alloying. In this work, the effect of grain size and relative density on the mechanical properties
were studied. The mechanical properties of sintered compacts were evaluated and compared with the reference samples fabricated
from the commercial SiC powder (β-SiC, 0.3 μm, IBIDEN Co., Gifu, Japan) with sintering additive (B–C mixture). The Vickers
hardness and bending strength of those sintered compacts increased with the increment of the density. However, the mechanical
properties were lower than those of reference samples in case of lower density, even though the mechanical property was close
to that of reference sample in case of higher density. This phenomenon was considered for the difference of bond strength
between grains because those sintered compacts were fabricated without any sintering additives, while those reference samples
were fabricated by accelerating the grain bonding with a sintering additive of B–C mixture. In other words, those results
indicated that the effect of sintering additive affected on mechanical properties directly.
This paper was presented at the International Symposium on Manufacturing, Properties, and Applications of Nanocrystalline
Materials sponsored by the ASM International Nanotechnology Task Force and TMS Powder Materials Committee on October 18–20,
2004 in Columbus, OH. 相似文献
238.
Ternary intercalation compounds of carbon fiber (ICCF) were successfully synthesized by soaking pitch-based carbon fibers in solvents such as 1,2-dimethoxyethane (DME) or tetrahydrofuran (THF) containing dissolved alkali metals (lithium, sodium, or potassium). ICCF with stage-1 and random stage was synthesized in alkali metal–DME and potassium–THF systems using different types of carbon fibers. However, ICCF with stage-1 could not be synthesized in lithium– or sodium–THF systems using carbon fibers with a low graphitization degree. Furthermore, the influence of the graphitization degree in the synthesis of ICCF was discussed. The graphitization degree of the host carbon fiber, in addition to the dimensions and steric structure of the intercalated complex affected the formation of TICCF. 相似文献
239.
The structure changes of Au nano-particles supported on CeO2 were observed by using an analytical transmission electron microscope (TEM) with a specimen heating holder. The disintegration and growth of Au particles on CeO2 were successfully observed in the atomic scale. In situ observation of Au particles at elevated temperature reveals that the Au particles on CeO2 grow by Ostwald ripening process through surface diffusion. Iridium particles on CeO2 were also observed during the heating process for comparison. The growth mode of Au particles is quite different from that of Ir. 相似文献
240.