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51.
Antigen coating on polystyrene is prevented by detergent. We present here a simple procedure to coat detergent-solubilized antigen for subsequent panning selection of single-chain Fv (scFv), the target antigen of which was the hepatitis C virus (HCV) non-structural protein (NS) 4B, an integral membrane protein.  相似文献   
52.
Aimed at providing small high‐power motors with excellent efficiency, a motor stator with rectangular‐wire lap windings and an automatic process for its production were developed. The structure of the windings, namely, two continuous “α‐shaped” coils, and the coil‐production method (involving simultaneous coil forming and coil insertion) enable mass production of this stator. The slot‐fill rate for a prototype stator was 80.5%, and the total height of the coil ends was 60 mm to 72 mm. On the basis of the ratio of the sectional areas of two types of the motors, its efficiency was estimated to be 3.7% higher than the efficiencies of motor stators with round‐wire concentric windings (at a rotation speed of 1000/min). In addition, the number of coil parts and the number of welding points were greatly reduced compared to those of a stator with segmented‐coil wave windings.  相似文献   
53.
The tracer monitored titration (TMT) technique is evaluated for measurement of dissolved oxygen. The TMT developed in this work uses a simple apparatus consisting of a low-precision pump for titrant delivery and an optical detector based on a white LED and two photodiodes with interference filters. It is shown that the classic Winkler method can be made free of routine volumetric and gravimetric measurements by application of TMT theory, which allows tracking the amounts of titrant and sample using a chemical tracer. The measurement precision of the prototype setup was 0.3% RSD.  相似文献   
54.
The science and an overview of the Soft X-ray Spectrometer onboard the STRO-H mission are presented. The SXS consists of X-ray focusing mirrors and a microcalorimeter array and is developed by international collaboration lead by JAXA and NASA with European participation. The detector is a 6×6 format microcalorimeter array operated at a cryogenic temperature of 50 mK and covers a 3′×3′ field of view of the X-ray telescope of 5.6 m focal length. We expect an energy resolution better than 7 eV (FWHM, requirement) with a goal of 4 eV. The effective area of the instrument will be 225 cm2 at 7 keV; by a factor of about two larger than that of the X-ray microcalorimeter on board Suzaku. One of the main scientific objectives of the SXS is to investigate turbulent and/or macroscopic motions of hot gas in clusters of galaxies.  相似文献   
55.
Quorum sensing (QS) is a process by which bacteria communicate using secreted chemical signaling molecules called autoinducers (AIs). By this process, many bacterial species modulate the expression of a wide variety of physiological functions in response to changes in population density. In this study, the periodontal pathogen Eikenella corrodens was observed to secrete type 2 signaling molecules. An ortholog of luxS, the gene required for AI-2 synthesis in Vibrio harveyi, was isolated from the E. corrodens genome. A V. harveyi bioassay showed luxS functionality in E. corrodens and the ability of luxS to complement the luxS-negative phenotype of Escherichia coli DH5alpha. AI activity was detected in the supernatant, and the maximum expression of AI-2 was observed during the late exponential phase. To determine the potential role of luxS in the colonization processes, an E. corrodens luxS mutant was constructed and tested for its capacity to form an in vitro biofilm on a polystyrene surface. The biofilm forming efficiency of the luxS mutant was approximately 1.3-fold greater than that of the wild type. These data suggest that a LuxS-dependent signal plays a role in the biofilm formation by E. corrodens.  相似文献   
56.
The paper deals with simultaneous optimization of path planning of mobile robots and flow shop scheduling problem. The goal of the path planning problem is to determine an optimal collision-free path between a start and a target point for a mobile robot in an environment surrounded by obstacles. The objective is to minimize the path length without colliding with an obstacle. On the other hand, shop scheduling problems deal with processing a given set of jobs on a given number of machines. Each operation has an associated machine on which it has to be processed for a given length of time. The problem is to minimize the overall time demand of the whole process. In this paper, we deal with two robots carrying items between the machines. Bacterial memetic algorithm is proposed for solving this combined problem. The algorithm is verified by experimental simulations and compared to classical techniques.  相似文献   
57.
Alzheimer’s disease is a chronic neurodegenerative disorder and represents the main cause of dementia globally. Currently, the world is suffering from the coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a virus that uses angiotensin-converting enzyme 2 (ACE2) as a receptor to enter the host cells. In COVID-19, neurological manifestations have been reported to occur. The present study demonstrates that the protein expression level of ACE2 is upregulated in the brain of patients with Alzheimer’s disease. The increased ACE2 expression is not age-dependent, suggesting the direct relationship between Alzheimer’s disease and ACE2 expression. Oxidative stress has been implicated in the pathogenesis of Alzheimer’s disease, and brains with the disease examined in this study also exhibited higher carbonylated proteins, as well as an increased thiol oxidation state of peroxiredoxin 6 (Prx6). A moderate positive correlation was found between the increased ACE2 protein expression and oxidative stress in brains with Alzheimer’s disease. In summary, the present study reveals the relationships between Alzheimer’s disease and ACE2, the receptor for SARS-CoV-2. These results suggest the importance of carefully monitoring patients with both Alzheimer’s disease and COVID-19 in order to identify higher viral loads in the brain and long-term adverse neurological consequences.  相似文献   
58.
59.
The through-plane water content distribution in a polymer electrolyte membrane (PEM) and in catalyst coated membranes (CCMs) and the flux of water through these membranes were determined under water permeation conditions by means of magnetic resonance imaging and dew point measurements. The PEM or CCM was placed in an experimental cell and subjected to water permeation conditions with various water activities across the membrane. A comparison of the water content distribution and the water flux in the various samples showed that the PEM and CCMs have different water transport properties. These differences suggested that diffusion through the membrane and interfacial transport across the membrane-gas interface, which are the rate determining processes for water transport through the membrane, change depending on whether the membrane has a catalyst coating.  相似文献   
60.
The phase separation behavior in a layer of an isobutyric acid (IBA)-water binary mixture was observed from the bottom and side of the layer, where the layer was subjected to a vertical temperature gradient spanning the critical temperature. As a result, the following conclusions were obtained. (1) Patterns characterized by a polygonal cell including one droplet, similar to those observed by Assenheimer et al. (Physica A 208 (1994) 373), were formed in a relatively thick liquid layer, e.g., thick, in a limited range of the temperature gradient, although the patterns ultimately disappeared. (2) The growth and extinction rates of the phase-separated droplets increased with ΔT/d, and increased particularly rapidly at high ΔT/d. (3) The formation of the pattern of polygonal cells each with a droplet is considered to be due to thermocapillary motion along the droplet. (4) The concentration-driven buoyancy convection affects the growth rate of the phase-separated droplets. (5) The extinction rate of the phase-separated droplets at the late stage is affected by the thermocapillary motion along the droplet surface.  相似文献   
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