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41.
Curing catalyst for epoxy resins was newly found. The catalyst consists of aluminum complex and silanol. Lack of one component of the pair does not cure epoxy resins. The epoxy resins cured with the catalyst are characterized by excellent electrical properties, especially at high temperature, due to the absence of strong acid species in the cured epoxy resin matrix. Heat-resistant property of the resin was also excellent. These properties were compared with those of epoxy resin cured with commonly used BF3 complex. 相似文献
42.
Ichiro Kudo Shoshichi Nojima Hyeun Wook Chang Ryohei Yanoshita Hidetoshi Hayashi Eri Kondo Hiroaki Nomura Keizo Inoue 《Lipids》1987,22(11):862-867
1-O-Octadecyl-2-O-methyl-sn-glycero-3-phosphocholine (ET-18-OMe) has been reported to possess definite antitumor activity in vivo. Twenty-two alkyl lysophospholipid analogs were chemically synthesized, and their antitumor activity against mouse experimental tumors (Sarcoma 180, MM46, P388) was examined. Among them, 1-O-octadecyl-2-O-acetoacetyl-rac-glycerol-3-phosphocholine was found to show antitumor activity similar to ET-18-OMe with less acute toxicity. Intravenous injection of the ET-18-OMe withsn-3 configuration retarded the subcutaneous growth of Sarcoma 180 cells effectively, while the growth inhibition by thesn-1 isomer was much less effective. This stereospecificity was similar to that observed in their activities as platelet-activating factor (PAF) agonists. The acetoacetyl compound, another PAF agonist, showed similar stereospecific antitumor action in vivo. These findings suggest that some alkyl lysophospholipids may activate host cells to a cytostatic stage against tumor cells in vivo through binding to a PAF receptor. Our preliminary results indicated that the responsible cells under these conditions might be primarily immature macrophages present in the bone marrow. No appreciable or even adverse stereospecificity was observed in the different sets of experiments where the activity of ET-18-OMe against MM46 tumor cells in vivo or the direct cytotoxicity against human promyelocytic leukemia HL-60 cells in vitro was examined. Under, some conditions, the antitumor activity of ET-18-OMe in vivo may be revealed through direct cytotoxicity and/or modulation of the host defense system by “nonspecific” mechanisms. Some alkylphospholipids without PAF activity may also show antitumor activity through similar, “nonspecific” mechanisms. 相似文献
43.
Hai -Hang Li Masafumi Inoue Hiroyuki Nishimura Junya Mizutani Eiji Tsuzuki 《Journal of chemical ecology》1993,19(8):1775-1787
Phenolic compounds have been identified as the most common allelochemicals produced by higher plants. Inhibitions of cinnamic acid, its related phenolic derivatives, and abscisic acid (ABA) on seedling growth and seed germination of lettuce were studied.trans-Cinnamic acid, ando-,m-, andp-coumaric acids inhibited the growth of etiolated seedlings of lettuce at concentrations higher than 10–4 M and seed germination above 10–3 M. Coumarin inhibited seedling growth and seed germination at 10–5 M or above. Chlorogenic acid inhibited seedling growth above 10–4 M, but did not inhibit seed germination at 10–5–5×10–3 M. Low concentrations (below 10–3 M) of caffeic and ferulic acids promoted the elongation of hypocotyls, but higher concentrations (over 10–3 M) inhibited seedling growth and seed germination. These phenolic compounds and abscisic acid had additive inhibitory effects both on seedling growth and seed germination. The inhibition on lettuce was reversed by caffeic and ferulic acids at concentrations lower than 10–3 M except for the inhibition of germination by coumarin. These results suggest that in naturetrans-cinnamic acid,o-, m-, p-coumaric acids, coumarin, and chlorogenic acid inhibit plant growth regardless of their concentration. However, caffeic and ferulic acids can either promote or inhibit plant growth according to their concentration. 相似文献
44.
Ichiro Kudo Toshiyuki Kato Hidetoshi Hayashi Ryohei Yanoshita Koichi Ikizawa Hiroko Uda Keizo Inoue 《Lipids》1991,26(12):1065-1070
We have previously reported that platelet-activating factor (PAF) induces proliferation and microbicidal activity of guinea
pig bone marrow cells. In the present study, we have found that the conditioned medium of PAF- or nonmetabolizable PAF agonist-treated
guinea pig bone marrow cells augmented DNA synthesis and induced microbicial activity of bone marrow cells. A PAF specific
antagonist, CV-6209, inhibited generation of the active conditioned medium by PAF. Addition of the PAF antagonist only partially
suppressed the augmentative effect of the active conditioned medium on DNA synthesis; this is consistent with the fact that,
because of the rapid breakdown, no appreciable amount of PAF remained in the conditioned medium of PAF-treated cells. Although
mouse bone marrow cells did not respond to PAF unlike guinea pig cells, their DNA synthesis was significantly enhanced by
the conditioned medium of PAF-treated guinea pig bone marrow cells. Thus, some newly generated factor(s) distinct from the
originally inoculated PAF seemed to modulate the bioactions of PAF on bone marrow cells. An appreciable amount of PAF was
produced by calcium ionophore-treated guinea pig bone marrow cells. These findings indicate that PAF synthesized in guinea
pig bone marrow cells induces generation in the cells of some factor(s) which affects proliferation or microbicidal activity.
Presented at The Third International Conference on Platelet-Activating Factor and Structurally Related Ether Lipids, Tokyo,
Japan, May 1989. 相似文献
45.
Two problems were solved theoretically on the heat transfer to circular tube flow with internal heat source. The one problem is to maintain the mixed-mean temperature of fluid at the inlet temperature. The other is a conjugated problem with a uniformly specified temperature at the outside surface of the wall, accounting for the wall conduction. From the numerical example for the former, it is shown that the mixed-mean temperature can be controlled within 15% error under the estimated condition. From the numerical results for the latter, it is concluded that the influence of wall conduction is more serious than the case without heat generation. 相似文献
46.
Recently, we revealed a standard pattern of a macroscopic molecular network for controlling morphogenetic processes such as the development of organs, including blast, mesoderm, heart, and hands during about sevenfold cell divisions and a standard bio-chemical clock like the circadian one (Naitoh in Artif Life Robot 13, 2008; Japan J Ind Appl Math 28(1), 2011; J Phys Conf Ser 344, 2012; Artif Life Robot 17, 2012) A network model derived logically based on experimental observations is described by a nonlinear differential equation for predicting time evolutions of six macroscopic molecular groups: three gene groups and three enzyme groups, which include promoting and suppressing factors. Here, the macroscopic model extended for also describing aging processes shows various types of cycles and reveals the physical condition for determining whether or not living beings such as humans can survive after getting ill. It is stressed that, after becoming ill, living systems with overly fast generation of information molecules such as various genes end in death, whereas relatively fast production of enzymes leads to recovery. This may also explain an essential feature underlying carcinogenic processes. 相似文献
47.
Hamid Noori Farhad Mehdipour Kazuaki Murakami Koji Inoue Morteza Saheb Zamani 《The Journal of supercomputing》2008,45(3):313-340
To improve the performance of embedded processors, an effective technique is collapsing critical computation subgraphs as
application-specific instruction set extensions and executing them on custom functional units. The problem with this approach
is the immense cost and the long times required to design a new processor for each application. As a solution to this issue,
we propose an adaptive extensible processor in which custom instructions (CIs) are generated and added after chip-fabrication.
To support this feature, custom functional units are replaced by a reconfigurable matrix of functional units (FUs). A systematic
quantitative approach is used for determining the appropriate structure of the reconfigurable functional unit (RFU). We also
introduce an integrated framework for generating mappable CIs on the RFU. Using this architecture, performance is improved
by up to 1.33, with an average improvement of 1.16, compared to a 4-issue in-order RISC processor. By partitioning the configuration
memory, detecting similar/subset CIs and merging small CIs, the size of the configuration memory is reduced by 40%. 相似文献
48.
Kenichi Mori Michiaki Sakamoto Jin Matsushima Daisuke Inoue Kenichirou Naka Ken Sumiyoshi 《Journal of the Society for Information Display》2009,17(6):513-518
Abstract— In order to improve the reflective contrast ratio of transflective IPS‐LCDs, a novel pixel design for a normally white reflective IPS has been proposed. In this design, the large‐inter‐electrode‐spacing layout using a novel driving method and a double‐layered electrode have effectively reduced the light leakage. By applying these two technologies, a transflective IPS‐LCD has been successfully demonstrated with a high contrast ratio (15:1) in the reflective mode and a wide‐viewing‐angle characteristic in the transmissive mode. 相似文献
49.
Yuichi Ogawa Nobuyuki Inoue Jifang Wang Takashi Yamamoto Kunihiko Okano 《Journal of Fusion Energy》1995,14(4):353-359
Based on scientific databases adopted for designing ITER plasmas and on the advancement of fusion nuclear technology from the recent R&D program, a low wall-loading DEMO fusion reactor has been designed, where high priority has been given to the early and reliable realization of a tokamak fusion plasma over the cost performance. Since the major radius of this DEMO reactor is chosen to be 10 m, plasma ignition is achievable with a low fusion power of 0.8 GW and an operation period of 4–5 hours is available only with inductive current drive. The low ignition power makes it possible to adopt a first wall with an austenitic stainless steel, for which significant databases and operating experience exists, due to its use in the presence of neutron irradiation in fission reactors. In step with development of advanced materials, a step-wise increase of the fusion power seems to be feasible and realistic, because this DEMO reactor has the potential to produce a fusion power of 5 GW. 相似文献
50.
Pouliquen M. Denoual M. Jorel C. Radu C. Robbes D. Grand J. Awala H. Mintova S. Harnois M. Sagazan O. de Inoue S. Lebrasseur E. Yamada K. Okamoto Y. Mita-Tixier A. Mita Y. 《Microsystem Technologies》2022,28(6):1313-1319
Microsystem Technologies - We demonstrate a new operation mode of thermal gas sensor based on thermal capacity extraction with identification algorithm. The system is a silicon microstructure... 相似文献