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31.
This paper proposes a road-to-vehicle communication system based onfiber-radio extension link (FREx link). Since the proposedroad-to-vehicle communication system interconnects a cell controlstation with base stations by FREx link, optical fiber link noiseshould be taken into account to evaluate the system. This paperanalyzes the outage probability and frequency utilization efficiencyperformance of the fiber-radio road-to-vehicle communication systemwith macro-diversity. It also shows that the proposed system withmacro-diversity can improve performance, although it should bedesigned with the effect of optical fiber link noise in mind.  相似文献   
32.
Triple-negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes. Recently, the activation of NF-κB, which is involved in the growth and survival of malignant tumors, has been demonstrated in TNBC, suggesting that NF-κB may serve as a new therapeutic target. In the present study, we examined whether dimethyl fumarate (DMF), an NF-κB inhibitor, induces apoptosis in TNBC cells and enhances the apoptosis-inducing effect of paclitaxel and adriamycin. Cell survival was analyzed by the trypan blue assay and apoptosis assay. Protein detection was examined by immunoblotting. The activation of NF-κB p65 was correlated with poor prognosis in patients with TNBC. DMF induced apoptosis in MDA-MB-231 and BT-549 cells at concentrations that were non-cytotoxic to the normal mammary cell line MCF-10A. Furthermore, DMF inhibited NF-κB nuclear translocation and Survivin, XIAP, Bcl-xL, and Bcl-2 expression in MDA-MB-231 and BT-549 cells. Moreover, DMF enhanced the apoptosis-inducing effect of paclitaxel and adriamycin in MDA-MB-231 cells. These findings suggest that DMF may be an effective therapeutic agent for the treatment of TNBC, in which NF-κB is constitutively active. DMF may also be useful as an adjuvant therapy to conventional anticancer drugs.  相似文献   
33.
Properties and mechanisms of fast-setting calcium phosphate cements   总被引:4,自引:0,他引:4  
The setting time of a calcium phosphate cement consisting of tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA) was reduced from 30 to 5 min by use of a cement liquid that contained a phosphate concentration of 0.25 mol/l or higher. The diametral tensile strength and conversion of the cement ingredients to hydroxyapatite (OHAp) during the first 3 h were also significantly increased by the phosphate. However, the phosphate produced no significant effects on the properties of the 24-h cement samples. Results from additional experiments in a slurry system verified that the high phosphate concentration in the solution accelerated the formation of OHAp in the TTCP + DCPA system, and this reaction could explain the fast-setting properties of the cements.Certain commercial materials and equipment are identified in this paper to specify the experimental procedure. In no instance does such identification imply recommendation or endorsement by the American Dental Association or National Institute of Standards and Technology or that the materials or equipment identified is necessarily the best available for the purpose.  相似文献   
34.
The precipitation behavior of MnS after solidification was analyzed with low-carbon Fe−Si alloys. This system was chosen since it has a wide temperature range for the δ/γ transformation. Experimental results showed that the amount of MnS precipitates increased drastically between 1300°C and 1100°C, and MnS precipitates were segregated almost entirely in the δ phase. This result was interpreted quantitatively by a mathematical model, taking into account the diffusion and the redistribution of solute elements and also the solubility product limit of Mn and S in both phases. Mathematical analysis shows that the precipitation of MnS starts first in the γ phase, but its growth will be very limited because of slow diffusion of Mn in the γ phase. The effects of some factors such as cooling rate and Si content of alloys on the rate of precipitation were discussed, and the degree of contributions of diffusion of Mn and the redistribution of S were estimated.  相似文献   
35.
36.
Aphytis yanonensis De Bach & Rosen, a parasitic wasp of the arrowhead scale,Unaspis yanonensis (Kuwana), was introduced to Japan to controlU. yanonensis. A. yanonensis recognizes a host insect by antennal contact and deposits eggs on the insect body underneath the scale. Ovipositional behavior is induced by perceiving the cuticular wax of the host insect,U. yanonensis, and other coccoids. Chemical composition of the cuticular wax was analyzed and oviposition stimulants were isolated following a bioassay usingA. yanonensis.  相似文献   
37.
Females of the larval parasitoidApanteles kariyai (Watanabe) (Hymenoptera: Braconidae) are arrested on fecal pellets ofAcantholeucania loreyi (Duponchel) (Lepidoptera: Noctuidae) larvae. Upon subsequent antennal contact with anA. loreyi larva, females sting it with their ovipositor. However, such stinging did not result in any offspring. The allelochemical involved in feces has been identified and is identical to a kairomone of the hostPseudaletia separata (Lepidoptera: Noctuidae). In contrast toA. loreyi, P. separata is a suitable host forA. kariyai, and oviposition inP. separata results in offspring production. The allelochemical mediating the interaction betweenA. loreyi andA. kariyai is discussed in the context of current allelochemical terminology.  相似文献   
38.
Field emission properties from diamond particles (DPs) are studied. The DPs with thin chemically vapor deposited (CVD) diamond overcoat, dispersed onto metal substrate, essentially exhibit negative electron affinity (NEA). Field emission, approximately 1mA/cm(2) under a macroscopic electric field of 3.5kV/mm are observed. Microscopic electrical properties were studied by scanning tunneling microscopy/spectroscopy. Most parts of the DP surface exhibit narrow gap and p-type characteristics. The localized regions, which have wide gap like bulk diamond properties, are randomly distributed near the top of DP. The field emission current distribution depicted by scanning field emission microscopy (SFEM) show that the electron emission is originating from a localized region on the selected DPs. We found, through SFEM measurement, some favorable field emission spots ("hot spots") where measured emission current is several orders higher than that of the other DPs ("normal spots"). Field emission spectroscopy (FES) results suggest that a poorly conducting layer is present along the electron path from the metal electrode to vacuum.We propose two models for field emission from "hot spots", which involve two main mechanisms. One is electron injection from the metal substrate to the DP, which is attributed to the electric field enhancement at intrinsic non-doped diamond (i-diamond) layer sandwiched between the metal substrate and the surface conductive layer (p-diamond) of the CVD diamond overcoat on the DP. The other is electron emission at the top site of NEA DP through the local i-diamond region or the depletion region of the p-diamond, which is caused by the applied electric field.  相似文献   
39.
Probabilistic Latent Semantic Analysis (PLSA) is proven to be effective in the information retrieval and the speech recognition technique. In this paper, we modify the calculation procedure of estimation algorithm. It substantially reduces the memory requirements. And, parallelization approach enables making models in less time. Next, we examined data segmentation for PLSA adaptation. Most meetings have a number of topics. We divide the meeting automatically and fit PLSA models with them. The experiment showed recognition performance improvement.  相似文献   
40.
Novel luminescent material has been prepared by the reaction of Eu3+ and molybdate species in the matrix of faujasite (FAU) type zeolite X and successive calcination. Eu3+ exchanged FAU was reacted with MoO3 in the solid-state at 723 K, giving a precursor. By calcining it at 1073 K, different crystalline phases were derived depending on MoO3-loading levels. Scheelite type crystal of NaEu(MoO4)2 was formed at high MoO3-loading levels, whereas europium sodalite was formed at low loading levels. For the former sample, X-ray diffraction analysis and transmission electron microscopy revealed that the nanosized NaEu(MoO4)2 was dispersed homogeneously within amorphous aluminosilicate matrix originated from FAU. The amorphous particles containing NaEu(MoO4)2 maintained the original morphology, which the starting FAU particles possessed. The emission intensity of nanosized NaEu(MoO4)2 in the matrix was one order higher than that of europium sodalite. The emission lifetime of nanosized NaEu(MoO4)2 (0.39 ms) in the matrix was longer than that of bulk NaEu(MoO4)2 (0.35 ms) fabricated by conventional solid-state processes.  相似文献   
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