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81.
A molecular valve, consisting of poly(acrylic acid) gel-coated Au mesh, was developed based on volume change of the gel in response to cation concentration. The valve closed when concentration of cations such as H+, Na+, K+, Ca2+, Cu2+, or Al3+ was low, whereas opened upon increase in its concentration. The valve re-closed when water was flowed. The concentration where the valve opens was found to increase in the order of Al3+, Ca2+, and Na+ (2 × 10−4, 5 × 10−4, and 6 × 10−3 M, respectively). The response to Cu2+ ion showed similar behaviour, but the opening concentration was ca. 2 × 10−4 M, which is lower than that of Ca2+ ion. The valve appeared to close over the pH range from 3 to 12, whereas to open below and above it. The fastest response time to open the valve (less than 1 min) was obtained for a solution of pH 1–2. The valve showed repeatability at least 25 cycles upon successive loading of a solution of pH 2 and water. Effects of anions and pressure were also studied. 相似文献
82.
Takano Masahito Iwashita Yuki Nagumo Kent Oiwa Kosuke Nozawa Akio 《Artificial Life and Robotics》2023,28(2):394-402
Artificial Life and Robotics - The amount of blood under the surface of skin is controlled by the autonomic nervous system and directly influences the facial skin temperature. Classification models... 相似文献
83.
Takahiro Kawashima Tsuyoshi Kimura Takayuki Shibata Akio Kishida Takashi Mineta Eiji Makino 《Microelectronic Engineering》2010,87(5-8):704-707
In order to realize cellular network analysis on a chip-based system, our group has been developing a patterned cell culture microdevice with pillars in an array for tapping cells into space surrounded by the pillars. The pillar structures has advantages to trap both adhesive and non-adhesive cells and to precisely control positions of cells and distances between cells for understanding effects of various cell patterns on functions of a cellular network such as cell proliferation, differentiation, and network formation. In this paper, HeLa cell cultivation with the patterned cell culture microdevice having a pillar array fabricated by dry film of thick negative photoresist SU-8 on a glass substrate was executed as a feasibility study on a cellular network analysis. The results revealed that the device performance was found to be enough to culture HeLa cells for more than 48 h. In addition, relative extensibility of blocks of multiple cells compared with single cells tapped on the device was observed. Thus, the patterned cell culture microdevice proposed here could be applicable to analysis of cellular functions. 相似文献
84.
Shigemitsu Hatanaka Eisuke Sakamoto Naoki Mishima Akio Muramatsu 《Materials and Structures》2008,41(7):1235-1249
The strength and hardness of concrete slab surface is considered significantly affected by bleeding of concrete. It has been
reported that dewatering by vacuum processing is quite effective to obtain high density of concrete. The method, however,
has not been successfully used for the concrete work in the field of building construction, compared with that of civil engineering
works in Japan. In the present study, firstly the state of the art concerning vacuum dewatering method is reviewed and the
newly improved vacuum dewatering method is introduced. Then the effect of the proposed method on concrete properties of slab
is examined by a series of experiments in order to find more reasonable and effective way in the application of the proposed
method. 相似文献
85.
Yuko Hamabe Ryoko Matsuura Akinori Jyo Masao Tamada Akio Katakai 《Reactive and Functional Polymers》2009,69(1):1-8
Bifunctional fibers containing phosphonate and sulfonate were derived from chloromethylstyrene grafted polyolefin fibers (PPPE-g-CMS) by phosphorylation and subsequent sulfonation reactions. It was clarified that phosphorylation of PPPE-g-CMS by Arbusov reaction is more suitable than one by the reaction with PCl3 in the presence of AlCl3, because the latter damaged fibers and gave phosphinate groups in addition to phosphonate ones. Then, bifunctional fibers containing phosphonate and sulfonate groups were prepared by sulfonation of monofunctional phosphonate fibers obtained via Arbusov reaction with chlorosulfonic acid. The metal ion selectivity of the bifunctional fibers was governed by both phosphonate and sulfonate groups. In addition, bifunctional fibers gave much more excellent kinetic performances in column-mode uptake of Cu(II) than the monofunctional phosphonate fibers and resin. 相似文献
86.
Masayuki Mizumoto Takeshi Ohgai Akio Kagawa 《Journal of Materials Processing Technology》2009,209(9):4264-4267
The SiCP/Al–4 mass%Cu alloy composites fabricated by a low-pressure infiltration process (LPI process) were remelted and separated by nozzle filtering method. In the separation process, the PRMMC specimen was placed in a container with a small nozzle at the bottom. The molten PRMMC was forced to flow out through the nozzle by applying a certain pressure of Ar gas. Most of the molten matrix alloy flowed out through the nozzle and the remainder in the container consisted of SiC particles and a part of the matrix alloy. The particle volume fraction of the remainder was higher than that of the original PRMMC and the remainder would work as a filter to separate SiC particles from the matrix alloy melt. When nozzle tip angle was ranged from 60° to 120°, about 80% of matrix alloy in the PRMMC was separated and few SiC particles were observed in the separated matrix alloy. The surface of recovered SiC particles became slightly roughened due to the reaction with the molten matrix during the separation process. However, this is not expected to affect their reuse. 相似文献
87.
Hajime Haneda Isao Sakaguchi Akio Watanabe Takamasa Ishigaki Junzo Tanaka 《Journal of Electroceramics》1999,4(1):41-48
18O diffusion coefficients were measured in zinc oxide ceramics using a secondary ion mass spectrometer. The results are interpreted as indicating extrinsic behavior. The values of the lattice diffusion coefficients with higher valence dopants compared with zinc ions are greater than lower valence dopant such as lithium ions. Using the data at deeper depth, the grain boundary diffusivity of oxide ions was also evaluated. Although the lattice diffusion coefficients varied by two orders of magnitude, the products of grain boundary width and grain boundary diffusion coefficient were less sensitive to the type of dopants. 相似文献
88.
Summary The binding of fibrinogen with heparin and dextran sulfates, and of antithrombin III with heparin and dextran sulfate were investigated by sedimentation velocity method. From the measurement of fibrinogen-acidic polysaccharide systems, it was confirmed that heparin and low molecular weight dextran sulfate(DSC) forms soluble complexes with fibrinogen, though the amount bound of the latter was rather small compared with high molecular weight dextran sulfate(DSD). Antithrombin III was also found to be bound by heparin and DSC. The numbers of heparin molecules bound to one molecule of fibrinogen and antithrombin III were estimated to be 4.2 and 0.3, respectively. 相似文献
89.
Two-fluid equilibria encompass more physics than the Grad–Shafranov (GS) equation for static equilibria, or even the flowing
MHD model. However the two-fluid system is more complicated, and, worse yet, is a singular perturbation problem. The latter
difficulty is overcome using the “nearby-fluids” ordering. A “1.5D” solution method has been used to interpret results from
the TCS experiment. These results, summarized here, exhibit trends indicative of the improved stability and transport observed
experimentally. An algorithm for solving 2D equilibria has been developed based on a relaxation method. The magnetic flux
function, governed by the extended GS equation, is updated by successive-overrelaxation, while the toroidal field and flow
components and the density are updated using a Newton–Raphson-like method. 相似文献
90.
Takeshi Kikuchi Makio Mogi Iichiro Okabe Kosuke Okada Hisashi Goto Yasuyuki Sasaki Takeki Fujimura Mitsuo Fukuda Akio Mitani 《International journal of molecular sciences》2015,16(10):24111-24126
Periodontal disease is caused by dental plaque biofilms, and the removal of these biofilms from the root surface of teeth plays a central part in its treatment. The conventional treatment for periodontal disease fails to remove periodontal infection in a subset of cases, such as those with complicated root morphology. Adjunctive antimicrobial photodynamic therapy (aPDT) has been proposed as an additional treatment for this infectious disease. Many periodontal pathogenic bacteria are susceptible to low-power lasers in the presence of dyes, such as methylene blue, toluidine blue O, malachite green, and indocyanine green. aPDT uses these light-activated photosensitizer that is incorporated selectively by bacteria and absorbs a low-power laser/light with an appropriate wavelength to induce singlet oxygen and free radicals, which are toxic to bacteria. While this technique has been evaluated by many clinical studies, some systematic reviews and meta-analyses have reported controversial results about the benefits of aPDT for periodontal treatment. In the light of these previous reports, the aim of this review is to provide comprehensive information about aPDT and help extend knowledge of advanced laser therapy. 相似文献