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11.
A rapid 5'-labeling method of single-stranded DNA/RNA was developed, which is based on the utilization of an adenylated intermediate in the reaction of T4 RNA ligase. This method is commonly useful for fluorescence-, isotope- or biotin-labeling of the 5'-ends of both oligo- and polynucleotides.  相似文献   
12.
Long terminal repeats of feline leukemia viruses cloned from feline acute myeloid leukemias frequently contained direct repeats of 40 to 74 bp in the upstream region of the enhancer (URE). The repetitive URE conferred an enhancer function upon gene expression in myeloid cells, suggesting its association with tumorigenic potential in myeloid cells.  相似文献   
13.
In this paper, a new method for secure remote biometric authentication preventing the vulnerability of compromised biometrics is presented. The idea is based on a public-key cryptographical protocol, referred as zero-knowledge proof, which allows a user to prove that she has surely a valid biometric data without revealing the data. Hence, the scheme is free from the risk of disclosure of biometric data. Even if a malicious administrator has a privilege access to the private database, it is infeasible for him to learn the private template. This paper studies two well-known definitions, the cosine correlation and the Euclidean distance as similarities of given two feature vectors. Both similarities are defined with some multiplications and additions, which can be performed in privacy-preserving way because of the useful property of public-key commitment scheme, additive homomorphism. The estimation based on the experimental implementation shows that the private Euclidean distance scheme archives better accuracy in terms of false acceptance and rejection than the private cosine coloration scheme, but it requires about $5/2 n \ell$ overhead to evaluate $n$ -dimension feature vectors consisting of $\ell$ -bit integers.  相似文献   
14.
The flow control of NaCl aqueous solution was examined by applying gas-liquid interface deformation induced by magnetic fields. Detailed studies of the dependence of flow velocity and concentration on the change in flow rate were carried out. In this experiment, with a flow on the order of 100 ml/min, the change in flow rate was measured under magnetic fields of up to 10 T. The flow rate decreased due to gas-liquid interface deformation at magnetic fields of about 6 T or more; the decrease in flow rate was approximately 23% at most. The change in flow rate was dependent on the flow velocity but not on the concentration. In addition, the possibility of using gas-liquid interface deformation induced by magnetic fields as a new means of controlling the flow of NaCl solution without contact was discussed.  相似文献   
15.
Laboratory Rainfall-Induced Slope Failure with Moisture Content Measurement   总被引:5,自引:0,他引:5  
The development of a physically based warning system for rainfall-induced slope failures requires a comprehensive understanding of the failure process. A set of laboratory-scale soil slopes was subjected to instability, through three different modes of raising water level, to clarify the process of failure initiation. Hydrologic responses of the model slopes to the saturation process were recorded by volumetric soil moisture content sensors. The results of model tests show that failures of the model slopes were essentially initiated by the development of an unstable area near the slope toe, upon the formation of the seepage area, with shallow noncircular sliding being the dominant failure mode. The volumetric moisture content of the slope region where localized failures initiated was noted to reach a nearly saturated value. However, the major portion of soil slopes involved in overall instability was still in an unsaturated condition. Based on the observed moisture content response of the model slopes, a concept for prediction methodology of rainfall-induced slope failures is introduced.  相似文献   
16.
Transmissive fractures or rock discontinuities (micro and macro) are mostly encountered when shafts and tunnels are excavated during the construction stage of underground space development or repositories for high level radioactive waste (HLW) disposal. These fractures may become flow paths to groundwater seepage and affect the stability of the excavated structure. For safe, effective construction and operation of such facilities, these fractures need to be sealed. In this study, the effect of ethanol on the injection characteristics of bentonite slurry as an effective grouting material is investigated. Various levels of ethanol concentrations (60%, 50% and 40%) were mixed with bentonite at liquid/solid ratios L/S (10, 8 and 6) by weight, w/w and injected into synthetic fracture of aperture sizes 100, 80 and 60 µm to investigate the penetrability of various concentrations of ethanol/bentonite slurries (EBS) into fractures of small aperture. Viscosity tests were also carried out to characterize the effect of ethanol on the rheological characteristics of the slurries. The results indicate that EBS is an effective grouting material capable of penetrating fractures of aperture sizes (100 µm–60 µm) and effectively sealing them for seepage control in the construction and operation stages of HLW repository. The results also showed that dynamic injection is more effective than static injection as it was able to inject high dense slurry into fractures better than static injection.  相似文献   
17.
Floods are a common feature in rapidly urbanizing Dhaka and its adjoining areas. Though Greater Dhaka experiences flood almost in every year, flood management policies are mostly based on structural options including flood walls, dykes, embankments etc. Many shortcomings of the existing flood management systems are reported in numerous literatures. The objective of this paper is to assess flood hazard in Greater Dhaka for the historical flood event of 1998 using Synthetic Aperture Radar (SAR) data with GIS data. Flood-affected frequency and flood depth calculated from the multi-date SAR imageries were used as hydrologic parameters. Elevation heights, land cover classification, geomorphic division and drainage network data generated from optical remote sensing and analogue maps were used through GIS approach. Using a ranking matrix in three dimensional multiplication mode, flood hazard was assessed. All possible combination of flood hazard maps was prepared using land-cover, geomorphology and elevation heights for flood-affected frequency and floodwater depth. Using two hazard maps which produced the highest congruence for flood frequency and flood depth, a new flood hazard map was developed by considering the interactive effect of flood-affected frequency and floodwater depth, simultaneously. This new hazard map can provide more safety for flood countermeasures because pixels belonging to higher hazard degrees were increased due to the consideration of higher degrees of ranks. The estimation of flood hazard areas revealed that a major portion of Greater Dhaka comprised moderate to very high hazard zone. Only a little portion (8.04%) was found to be the least vulnerable to potential flood hazard. Conversely, 28.70% of Greater Dhaka was found within very high hazard zone. Based on this study, comprehensive flood hazard management strategies for land use planning decision were proposed for the efficient management of future flood disasters.  相似文献   
18.
19.
A method to analyze in vivo metabolites in blood obtained from the hepatic vein after the intraportal injection of a drug was established. This method includes cannulation into the portal vein, hepatic vein and bile duct, followed by TLC-autoradioluminography of a non-extracted sample. Either [14C]diazepam, L-3,4-dihydroxyphenyL[3-(14)C]alanine or [14C]inulin was administered on the day following the surgical operation to avoid the influence of anesthesia. Radioactive concentrations of [14C]DOPA decreased rapidly in the first 1 min, then decreased gradually. The concentrations of [14C]diazepam increased within the first 1 min and then decreased gradually. The concentration of [14C]inulin was approximately 10 times higher than that of [14C]DOPA, and both decreased gradually. These results show that the uptake levels of the drugs to the liver varied depending on the drugs. The metabolites of [14C]diazepam and [14C]DOPA were detected as early as 5 s after administration. These results suggest that the in vivo hepatic first pass effect of drugs in the early period of injection (5 s) can be studied using these techniques.  相似文献   
20.
Microwave ceramic resonators composed of BaO-TiO2-WO3 were developed. The effect of WO3 addition on the system of BaO·xTiO2·(1+x)yWO3 (x=4 and 4.5, y=0 to 0.04) was studied. The ceramics of this system are composed of crystallines including Ba2Ti9O20, BaTi4O9, BaWO4, and TiO2. At y=0.02, the BaO·4TiO2·0.1WO3 ceramic was found to have excellent microwave properties such as ε=35, Q=8400 at 6 GHz, and nearly 0 ppm/°C of τf.  相似文献   
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