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61.
Lake whitefish (Coregonus clupeaformis) within the waters of Green Bay, Lake Michigan have recently shown a substantial increase in abundance. Furthermore, after over 100 years of extirpation, adult lake whitefish are found spawning within major Wisconsin tributaries to Green Bay. Many knowledge gaps still exist with respect to the chronology of adult river migrations, including the physical characteristics of upstream habitats selected for reproduction and the extent of larval production by these riverine ecotypes. Here, we use hydroacoustic imaging along with egg and larval surveys to evaluate this novel riverine spawning in 2017 and 2018. Highest abundance of adults was observed in the month of November as temperatures declined below 8 °C. Spawning areas consisted of cobble substrates, and site-specific fish densities were primarily correlated with river flows between 0.3 and 1.0 m/s, with specific values varying by tributary and year. Locations of egg deposition mirrored areas of high observed fish densities. Larval production was documented on each tributary using active trawl ichthyoplankton sampling, and larvae were observed outmigrating to open water environments. We estimated tributaries produced 452,000 larvae in 2017 and 721,000 larvae in 2018. To our knowledge, this represents the first documentation of successful lake whitefish larval production from Green Bay tributaries and suggests tributary spawning populations contribute to the greater abundance of lake whitefish observed in recent years.  相似文献   
62.
We demonstrate a low-loss 16-band dynamic gain equalization filter consisting of two perfectly sampled waveguide grating routers (WGRs) and an array of thermooptic attenuators. This integrated silica waveguide filter has <2.8-dB fiber-to-fiber insertion loss, <0.2-dB polarization-dependent loss at minimum attenuation and <0.7-dB at 10-dB extra attenuation, and <5.0-W electrical power consumption over the C-band. We also demonstrate a new technique for reducing the loss of WGRs  相似文献   
63.
The influence of cytomegalovirus (CMV) infection on the HLA expression on cultured biliary epithelial cells (BEC) was investigated. CMV-infection augmented expression of HLA class I but not of HLA class II. CMV reduced the IFN-gamma-mediated induction of the de novo expression of HLA class II while the stimulated expression of HLA class I was not impaired. Autologous but not allogeneic PBL responded to CMV-infected BEC. This response resulted in upregulation of HLA class I on BEC which was significantly higher compared with the expression on infected BEC alone or on uninfected BEC cocultured with autologous PBL. The results suggest that CMV modulates the immunogenic potential of BEC, which is important for the HLA and CMV-mediated pathomechanisms in vivo.  相似文献   
64.
A radioimmunoassay (RIA) for oestrone (Oe1) in plasma was developed using an ether extraction, a partition between NaOH and light petroleum, and a TLC as sample purification and an antiserum cross-reacting with Oe2 for the final assay (Method A1). The reliability criteria are given in detail. In order to simplify this method a highly specific antiserum was developed by using Oe1-3-hemisuccinate-BSA as an antigen. Using this antiserum for the final assay but omitting the TLC (Method B) the Oe1 concentration in male plasma was 76% overestimated (Method B compared with Method A1). In pregnancy plasma Oe1 could specifically be determined after a simple ether extraction (Method C). It was concluded that the use of a highly specific antiserum (as determined by cross-reaction studies) for the final assay does not necessarily imply that a chromatographic sample purification can be omitted without loss in assay specificity. This appears to be true mainly in cases where the steroid concentration of the sample is low. Normal values of Oe1 from 80 healthy adult males were ascertained by Method A1. Age group I (22-61 years, n = 48) ranged from 1.22-5.60 ng/100 ml, median 2.81; age group II (67-90 years, n = 32) from 1.55-6.40, 100 median 3.41. The small increase of Oe1 with age was highly significant.  相似文献   
65.
All-Optical Network Consortium-ultrafast TDM networks   总被引:3,自引:0,他引:3  
We describe recent results of the Advanced Research Projects Agency (ARPA) sponsored Consortium on Wideband All-Optical Networks which is developing architectures, technology components, and applications for ultrafast 100 Gb/s time-division multiplexing (TDM) optical networks. The shared-media ultrafast networks we envision are appropriate for providing low-access-delay bandwidth on demand to both future high-burst rate (100 Gb/s) users as well aggregates of lower-rate users (i.e., a heterogeneous user population). To realize these goals we are developing ultrafast network architectures such as HLAN, described here, that operate well in high-latency environments and require only limited processing capability at the ultrafast bit rates. We also describe results on 80-Gb/s, 90-km soliton transmission, 100-Gb/s soliton compression laser source technology, picosecond short-pulse fiber ring lasers, picosecond-accuracy optical bit-phase sensing and clock recovery, all-optical injection-locked fiber figure-eight laser clock recovery, short-pulse fiber loop storage, and all-optical pulse width and wavelength conversion  相似文献   
66.
Exploring the connections between successive phases and overlapping layers from different ages in an ancient building is paramount for its understanding and study. Archaeologists and cultural heritage experts are always eager to unveil the hidden relations of an archaeological building to reconstruct its history and for its interpretation. This paper presents CRMba, a CIDOC CRM extension developed to facilitate the discovery and the interpretation of archaeological resources through the definition of new concepts required to describe the complexity of historic buildings. The CRMba contributes to solving the datasets interoperability issue by exploiting the use of the CIDOC CRM to overcome data fragmentation, to investigate the semantics of building components, of functional spaces and of the construction phases of historic buildings and complexes, making explicit their physical and topological relations through time and space. The approach used for the development of the CRMba makes the model valid for the documentation of different kinds of buildings, across periods, styles and conservation state.  相似文献   
67.
Previous experiences during earthquake events emphasize the need for new technologies for real-time monitoring and assessment of facilities with high-value nonstructural contents. Moreover, there is a substantial limitation in our ability to rapidly evaluate and identify potential hazard zones within a structure, exposing rescue workers, society, and the environment to unnecessary risks. A real-time image-based monitoring system, which is integrated with warning systems, would allow for improved channeling of resources and informed decision making for rescue workers and building owners. In recognition of these issues, in this paper, we describe a methodology for image-based tracking of seismically induced motions. The methodology includes the acquisition, calibration, and processing of image sequences to detect and track object features under seismic-event conditions. We address the issue of providing a reliable feature/object-detection and object-tracking methodology for an image sequence from a single camera view. In addition, we introduce an extension to the 2-D tracking approach by providing a 3-D feature tracking methodology when the camera array itself is affected by the seismic event. The methods presented are demonstrated using the data collected during the full-scale field vibration tests conducted on a vacant building that was damaged during the 1994 Northridge earthquake (presented in a companion paper). We present experimental tracking results of the implemented algorithms for a variety of objects and discuss additional challenges that emerge when image-based systems are used under these extreme conditions.  相似文献   
68.
A novel 107-Gbit/s optoelectronic receiver has been designed using hybrid integration of a photodiode and electronic demultiplexer. Using an ETDM transmitter, we achieve the lowest reported required OSNR for 107-Gbit/s CSRZ-OOK, 21 dB for 10-3 BER and a 231-1pattern length. Design methodology and performance data are presented.  相似文献   
69.
Head direction (HD) cells have been speculated to be part of a network mediating navigational behavior. Previous work has shown that combined administration of serotonergic and muscarinic antagonists eliminates hippocampal theta activity and produces navigational deficits more severe than blockade of either neurotransmitter system alone. The authors sought to assess this effect on the directional characteristics of HD cells. HD cells were recorded from the anterior dorsal thalamus of Long-Evans rats before and after administration of the serotonergic antagonist methiothepin, the muscarinic antagonist scopolamine, both drugs, or saline. Combined drug administration produced HD cells with preferred directions that drifted within recording sessions. In addition, cells showed shifts in the preferred directions at the start of a session relative to the position of the major landmarks, suggesting that combined drug administration led to deficits in landmark control of the HD system. Single drug exposures to methiothepin or scopolamine did not noticeably affect the directional characteristics of HD cells. This finding that navigation-impairing drugs can disrupt the HD signal provides further evidence that this network plays an important role in navigational behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.
OBJECTIVE: To assess whether alterations in preoperative fatty acid oxidation and gluconeogenesis induced by fasting will affect survival and liver regeneration following 90% hepatectomy in the rat. DESIGN: In a randomized, controlled trial, Wistar rats (N = 157) were separated into two groups. Rats in the first group fasted for 24 hours. Rats in the second group were allowed to eat ad libitum until the time of operation. These groups were further randomized to receive either 20% glucose or tap water ad libitum postoperatively. INTERVENTIONS: Ninety percent hepatectomy; 24-hour fast; 5% glucose feeding. MAIN OUTCOME MEASURES: Survival, DNA synthesis in the hepatic remnant along with glucokinase activity (GKA) and glycogen content, serum ketone bodies (KB), free fatty acid (FFA), glucose, and ad libitum glucose consumption (GC) were serially quantified. RESULTS: Fasting rats that were offered glucose (fasted/glucose) after hepatectomy demonstrated better survival at 48 hours than the rats that were fed before the procedure and given glucose following hepatectomy (fed/glucose), 95% vs 52% (P < .05). The fasted/glucose group also had a greater peak rate of DNA synthesis (550 +/- 110 vs 275 +/- 40 disintegrations per minute per 0.001 mg of DNA, P < .05). Survival was poor in both groups when only tap water was offered to the animals after hepatectomy (31% vs 12%). In the fasted/glucose group, GC 1 hour after hepatectomy was greater than that for fed rats (1.3 +/- 0.175 vs 0.73 +/- 0.176 g/h, P < .05), yet GKA was suppressed (3.4 +/- 0.42 vs 8.05 +/- 2.77 nmol/min per milligrams of protein, P < .05). Fasting before hepatectomy and consuming glucose after causes elevations in both FFA (1.26 +/- 0.19 vs 0.82 +/- 0.13 mol/mL., P < .05) and KB (18.96 +/- 2.82 vs 11.4 +/- 3.94 mmol/mL, P < .05). Normal glucose was maintained in the fasted/glucose group, but fell to 63 +/- 14 mg/dL at 8 hours after hepatectomy in the fed/glucose group. CONCLUSIONS: Fasting before hepatectomy shifts energy utilization to fat oxidation and gluconeogenesis, which appears to ameliorate liver failure after hepatectomy in this severe model of hepatic resection.  相似文献   
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