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951.
We studied T cell responses to four glutathione S transferase (GST)-fused mite antigens prepared in our laboratory using peripheral blood lymphocytes from mite-sensitive patients with bronchial asthma. Of the four recombinant antigens, purified GST-Mag3 had the strongest ability to cause patients' lymphocytes to proliferate, and its potency was almost comparable to that of crude mite bodies (Dfb) and faeces (Dff) antigens and a purified major antigen, Der f 2. The responder lymphocytes were mainly T cells, because the proliferative response was depleted by the treatment of lymphocytes with anti-CD3 antibody and complement, but not with anti-CD20 antibody and complement. The responsiveness of lymphocytes to GST-Mag3 correlated with that to Der f 2, but GST-Mag3 displayed slightly higher activity to stimulate lymphocytes than Der f 2. Simultaneously, the levels of Dff- and GST-Mag3-specific IgE antibodies correlated with the responsiveness of lymphocytes to GST-Mag3. These results suggest that Mag3 is a new valuable antigen for the response of T cell proliferation in mite-sensitive patients. 相似文献
952.
Miyatake S. Miyamoto M. Ishida K. Morimoto T. Masaki Y. Tanabe H. 《Electron Devices, IEEE Transactions on》2003,50(1):121-129
Novel architecture for CMOS active pixel image sensors (APSs), which eliminates the vertically striped fixed pattern noise (FPN), is presented. There are two kinds of FPN for CMOS APSs. One originates from the pixel-to-pixel variation in dark current and source-follower threshold voltage, and the other from the column-to-column variation in column readout structures. The former may become invisible in the future due to process improvements. However, the latter, which results in a vertically striped FPN, is and will be conspicuous without some subtraction because of the correlation in the vertical direction. The pixel consists of a photodiode, a row- and column-reset transistor, a source-follower input transistor, and a column-select transistor instead of the row-select transistor found in conventional CMOS APSs. The column-select transistor is connected to a signal line that runs horizontally instead of vertically. An experimentally fabricated 320/spl times/240-pixel CMOS APS employing the transversal-readout architecture exhibited neither vertically nor horizontally striped FPN. A buried-photodiode device with the transversal-readout architecture is also proposed. 相似文献
953.
INTRoDUCTI0NTheCoandaeffectthatisanimportamconsequence0fthepressurevariati0nperpendiculart0curvdStreanilines,isthetendencyofafiuldjettoattaChitSelftoaconvexsolidb0dyoranadacentsurface.Inrec6Dtyears,theusefulnessoftheCoandaeffectisencowteredinawiderangeofaPplicationfromfiuldicdevicetoaircraftwingSandfiaPdevices[1~22l.Horiietal.I`-s]shOWdthatafocusedandhiglilystablesPiralfiowwasobtainedusinganozzlewithanannularslitconnectedtoaconicalcylinder.Toimprovthrustvectoring,Bevilaquaetal.[16jin… 相似文献
954.
M Maruyama M Ebuchi N Sugano S Takamatsu T Kudo 《Canadian Metallurgical Quarterly》1997,21(4):238-240
Clinical aspects of leg ulcers are reviewed. Among the most important factors to be kept in mind are: localisation, features of the ulcers and surrounding skin, clinical history and general physical examination. Leg ulcers are most frequently caused by vascular diseases. 相似文献
955.
Carbon beads have been prepared by the carbonization of naphthalene sulfonate formaldehyde (NSF) resin. The procedures for the preparation have been described in detail. The electrochemical performance of NSF carbon beads as an anode material for lithium batteries has been correlated with some carbonization factors such as the molecular weight of the precursor, the ramp rate, and final temperature, etc. 相似文献
956.
Carbon KVV Auger electron emission from highly oriented pyrolytic graphite bombarded by fast protons
Hiroshi Kudo Katsuhiro Haruyama Takao Kinoshita Seiji Seki Kazumasa Narumi Hiroshi Naramoto 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2002,190(1-4):160-163
We have studied carbon KVV Auger electron emission from highly oriented pyrolytic graphite (HOPG) by ion-induced 180° electron spectroscopy. In obliquely emitting directions across the HOPG (0 0 0 1) surface, the Auger peak yield induced by MeV protons becomes lower than in the surface normal direction. An analysis based on mean free path for inelastic scattering indicates that the observed reduction of the Auger yield can be explained by increased inelastic collisions with valence electrons above the surface. The experimental results provide information about the production sites of the KVV Auger electrons in the layer structure. 相似文献
957.
Yoshihiro Hirata Kazunori Hayata Tomoyuki Maeda Masaki Shibuya 《Journal of the American Ceramic Society》2004,87(6):996-1001
A polytitanocarbosilane (PTC, 20–50 mass%)–xylene solution was infiltrated into a porous, laminated woven fabric of 21–33 vol% Si-Ti-C-O fibers including 26–46 vol% mullite powder (filler) and decomposed at 1000°C in an argon atmosphere. This polymer impregnation and pyrolysis method (PIP) was repeated eight times to produce a laminated composite of 68%–85% of theoretical density. The effects of the polymer concentration and the fraction of mullite filler on the densification rate and microstructure of the layered composite were studied. The pseudoductility of the densified composite, as measured using four-point flexural testing, was caused by buckling after the elastic deformation and was followed by delamination along the direction of the layered fabric. The strength and the energy of fracture were enhanced by controlling the incorporation of mullite filler in the filament yarn (formation of a narrow pore-size distribution) and densification with a low-viscosity PTC solution. The composite with a higher strength provided a higher energy of fracture. The maximum energy of fracture reached 22 kJ/m2 in the composite with 330 MPa of strength in four-point flexure. 相似文献
958.
Mutoh N. Kaneko S. Miyazaki T. Masaki R. Obara S. 《Industrial Electronics, IEEE Transactions on》1997,44(1):54-63
A torque controller suitable for electric vehicles is studied. The controller ensures that an induction motor generates motor torque efficiently, stably and accurately. The torque control system feeds back an assumed motor torque calculated using the secondary magnetic flux and the torque current detected from current sensors of the primary currents. The motor torque is controlled by using the torque current reference determined from the generated secondary magnetic flux and the magnetizing current reference. The magnetizing current reference is determined on the basis of the torque current reference so that motor torque generation efficiency is always optimal. The magnetizing current regulator is operated according to the magnetizing current reference. This ensures the motor generates the motor torque stably even in transient states. Fundamental performance characteristics, such as response, accuracy and efficiency of the motor torque are verified by simulation and experiments. The torque controller is judged suitable for the drive system of electric vehicles 相似文献
959.
When rat serosal connective tissue mast cells (CTMC) were stimulated with nerve growth factor (NGF), the immediate prostaglandin D2 (PGD2) generation was followed by delayed PGD2 generation that occurred between 2 and 24 h, reaching levels as high as 50 ng and 260 ng/10(6) cells in the absence or presence of lysophosphatidylserine (lysoPS), respectively. This delayed PGD2 generation was accompanied by de novo induction of cyclooxygenase (COX)-2, with NGF and lysoPS acting as inducer and enhancer, respectively. COX-2 induction and the attendant delayed PGD2 generation in CTMC were modestly induced by c-kit ligand, but not by Fc epsilonRI cross-linking. This indicated that the stimulus specificity differed from that observed in the immediate phase, in which NGF, c-kit ligand, and Fc epsilonRI cross-linking, either in combination with each other or with lysoPS as a cofactor, elicited comparable levels of PGD2 generation within 10 min, reaching 10 to 20 ng/10(6) cells. Addition of type II secretory phospholipase A2 (sPLA2), a PLA2 isoform that is detected in microg/ml levels in inflammatory exudates, to NGF-stimulated CTMC significantly augmented delayed, but not immediate, PGD2 generation, and this augmentative effect was mediated in part by the enhancement of COX-2 expression by sPLA2. These results suggest that CTMC have the capacity to produce PGD2 over a prolonged period in the presence of tissue-derived cytokines and sPLA2 in a COX-2-dependent manner. 相似文献
960.
Y Osuga M Hayashi M Kudo M Conti B Kobilka AJ Hsueh 《Canadian Metallurgical Quarterly》1997,272(40):25006-25012
Gonadotropin receptors are unique members of the seven-transmembrane (TM), G protein-coupled receptor family with a large extracellular (EC) sequence forming the high-affinity ligand binding domain. In a patient with Leydig cell hypoplasia, we identified a mutant LH receptor that is truncated at TM5. This protein retains limited ligand binding ability but cannot mediate cAMP responses. To study interactions between receptor fragments defective in either ligand binding or signal transduction, we co-expressed this truncated receptor together with a chimeric receptor containing the EC region of the FSH receptor and the TM region of the LH receptor. Although the chimeric receptor could not respond to human chorionic gonadotropin in producing cAMP, co-expression with the truncated LH receptor allowed partial restoration of ligand signaling through intermolecular interactions. In addition, co-expression of the same truncated LH receptor with an N-terminally truncated LH receptor that lacked the EC ligand binding domain also partially restored ligand signaling. Further shortening of the TM region in the mutant receptor found in the patient indicated that the EC domain and TM1 were sufficient for interactions with the N terminally truncated receptor. In contrast, co-expression of the N terminally truncated receptor together with cell-associated or soluble EC region of the LH receptor did not allow ligand signaling. Unlike thrombin receptors, co-expression of the anchored EC region of the LH receptor together with the N-terminally truncated receptor did not allow ligand signaling despite moderate levels of human chorionic gonadotropin binding in transfected cells. These studies demonstrate that the co-expression of binding (+)/signaling (-) and binding (-)/signaling (+) receptor fragments partially restores ligand-induced signal generation and indicate the importance of TM1 of the LH receptor in the proper orientation of the EC ligand binding domain. 相似文献