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101.
Radio frequency identification (RFID) provides a more convenient and automatic approach for object identification than traditional universal product code-based barcode technology. However, radio communications are naturally unreliable and inevitably lead to unreliable object identification, which in turn encumber some special applications demanding large-scale deployment of RFID, even though many RFID applications have been emerging recent years. This paper discusses object identification reliability. We first list factors that could cause false readings and lead to unreliable object identification. Then we provide five definitions that directly and formally define object identification reliability. Based on these reliability-related definitions, a general framework for guaranteeing object identification reliability is proposed in this paper. Existing schemes for reliability improved are briefly compared within this framework.  相似文献   
102.
Biologically treated newsprint mill effluent containing 57 mg L−1 DOC and 1430 TDS was used in a screening study of nine commercial NF membranes for use as pretreatment for reverse osmosis in an end of pipe water recycling application. A salt-organic-separation (SOS) efficiency factor was developed to help rank the performance of the membranes. The SOS measures the ratio of the sum of the percentage rejection of organics and divalent cations over the percentage rejection of monvalents. It can be used to discriminate between NF membranes that are not too permeable to divalent cations or organics in which case the NF permeate will have a high chlorine demand due to the carryover of organics, or too retentive in which case all the material in the effluent will be retained and fouling problems are likely to occur. The optimum SOS efficiently for this study appeared to range from 3.5 to 5.6 for six membranes, DK, HPA-150, ESNA1-LF2, DL, TFC-SR2 and NF-270, which were categorised as membranes with an intermediate rejection. Out of these membranes ESNA1-LF2, TFC-SR2 and NF-270 were capable of operating up to 90% recovery with high permeabilities ranging from 17.7 to 22.3 L m−2 h−1 bar−1.  相似文献   
103.
We describe the use of readily available crosslinked poly(4-vinylpyridine) supported sodium thiobenzoate, [P4VP]SCOPh, in the suspended solution phase synthesis of S-alkyl thiobenzoate at room temperature in high yields. The spent polymeric reagent can be removed quantitatively by filtration and pure products can be obtained by evaporation of the solvent. The spent polymeric reagent can be regenerated and reused for several times. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
104.
Predicting the dynamic response of submerged vehicles subjected to hydrostatic pressure and underwater shock loading is of great interest to many structural designers and engineers for improving material and configuration design in recent years. In this paper, the finite element method is used to evaluate the dynamic response of a submerged cylindrical foam core sandwich panel subjected to shock loading. The sandwich panel consists of a foam core surrounded by fiber-reinforced laminates. The effect of fluid–structure coupling is included in the finite element analysis whereas the fluid is assumed to be compressible and inviscid. Time histories of circumferential stress for different composite plies are presented in graphical form and the effects of core type on circumferential stress and velocity of stand-off point are also investigated. Additionally, the distribution of pressure in fluid domain and the deformation of cylindrical foam core sandwich panel are estimated. To the best of the authors’ knowledge, the specialized literature addressing the dynamic response of submerged cylindrical foam core sandwich panel to underwater shock loading is rather scanty. This work is likely to fill a gap in the specialized literature on this topic.  相似文献   
105.
Wetted rice particles were dried in a fluidized bed and the corresponding passive acoustic emissions signals (AES) were recorded at a given frequency to study the drying phenomena and bed hydrodynamic changes as well. The results show that the end time of the constant rate zone and the end of the falling rate can be determined from the variation of standard deviation and kurtosis of AES, respectively. Frequency domain analysis was also used to quantify the moisture content of solids. For this end, the original signal was decomposed into ten sub-signals, and it was found that the energy of the 4th sub-signal can be correlated with the moisture content. The results show that the acoustic emission measurement is applicable as a practical method for on-line condition monitoring of drying process in fluidized bed dryers.  相似文献   
106.
RNA interference (RNAi) is an emerging technology in which the introduction of double-stranded RNA (dsRNA) into a diverse range of organisms and cell types causes degradation of the complementary mRNA. It offers a broad spectrum of applications in both biological and medical research. Small interference RNA (siRNA) was recently explored for its therapeutical potential. However, the drug delivery of siRNA oligos is very novel and is in great need of future research. To this end, a biodegradable poly(D,L-lactide-co-glycolide) (PLGA) nanoparticle drug carrier system was prepared to load siRNA oligos with desired physicochemical properties. The nanoparticles were characterized by scanning electron microscopy and laser diffraction particle sizer. The delivery of siRNA into the targeted 293T cells was observed using fluorescent-labeled double-stranded Cy3-oligos. The model siRNA oligos, si-GFP-RNA, were also successfully loaded into PLGA nanoparticles and delivered in 293T cells. The gene silencing effect and the inhibition of GFP expression were investigated using fluorescent microscopy. Both positive and negative controls were used to compare with the new siRNA nanoparticle delivery system. It was found that nanoparticles offered both effective delivery of siRNA and prominent GFP gene silencing effect. Compared to conventional carrier systems, the new biodegradable polymeric nanoparticle system may also offer improved formulation stability, which is practically beneficial and may be used in the future clinical studies of siRNA therapeutics.  相似文献   
107.

Lingering droughts and shortage of water sources signify the importance of optimal utilization of water reservoirs such as multi-reservoir systems. These systems could be employed not only as a storage system to manage the water utilization but also as a power generation system. To rise the generated power besides the management of water utilization, an optimization algorithm should be used. In this study, the kidney algorithm in three different scenarios, namely the wet, normal, and dry years is employed to fulfill such an engineering operation in a four-reservoir system in China. Simulations show well compatibility of the water level inside the reservoir with real statistical indices in terms of RMSE and MAE. Results also reveal that using the kidney algorithm not only reduces the required calculation but also increases the convergence pace with respect to other algorithms that have been used (bat, shark, abundance of particles, and genetic algorithms). Moreover, it increases the amount of the generated energy by a factor of 2.2–3.2 with respect to the aforementioned algorithms. Results indicate the capability of the kidney algorithm in the management of water sources and engineering operations.

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108.
This paper reports the design and fabrication of bulk mode micromechanical disc resonators operating in radial and wine-glass modes of excitation. The reported structures are fabricated utilizing a single crystal SOI wafer through micromachining processes. Both resonators are fabricated on a device layer with a thickness of 20 µm and a gap size of 1.75 µm between the resonant beam and surrounding electrodes. Four anchors support the resonant disc using a T-shaped connection stem. The designed structures resonate at 2.87 and 3.99 MHz, in wine glass and radial modes respectively, and are electrostatically actuated by a DC voltage of 110 V between the disc and electrodes. The designed resonators show high quality factors while operating in air, 1,1876.2 for wine-glass and 7380 for radial. In addition, the resonators are used for distributed and point mass measurements of a sputtered gold metal layer. The wine glass resonator shows a frequency down shift of 1 kHz for a 44 ngr gold point mass, and a frequency shift of 22 kHz for a distributed mass of 83 µgr. Same test is performed on radial mode resonator and a resonance frequency shift of 1.24 and 25.54 kHz was observed for point and distributed mass, respectively in air and at room temperature.  相似文献   
109.
This paper introduces a workload characterization study of the most popular short video sharing service of Web 2.0, YouTube. Based on a vast amount of data gathered in a five-month period, we analyzed characteristics of around 250,000 YouTube popular and regular videos. In particular, we collected lists of related videos for each video clip recursively and analyzed their statistical behavior. Understanding YouTube traffic and similar Web 2.0 video sharing sites is crucial to develop synthetic workload generators. Workload simulators are required for evaluating the methods addressing the problems of high bandwidth usage and scalability of Web 2.0 sites such as YouTube. The distribution models, in particular Zipf-like behavior of YouTube popular video files suggests proxy caching of YouTube popular videos can reduce network traffic and increase scalability of YouTube Web site. YouTube workload characteristics provided in this work enabled us to develop a workload generator to evaluate the effectiveness of this approach.  相似文献   
110.
The focus of this study is on a rapid and cost‐effective approach for the synthesis of silver nanoparticles (AgNPs) using Artemisia quttensis Podlech aerial parts extract and assessment of their antioxidant, antibacterial and anticancer activities. The prepared AgNPs were determined by ultraviolet–visible spectroscopy, X‐ray diffraction, Fourier transform infra‐red spectroscopy, transmission electron microscopy, scanning electron microscopy, energy‐dispersive spectroscopy, and dynamic light scattering and zeta‐potential analysis. The AgNPs and A. quttensis extract were evaluated for their antiradical scavenging activity by 2, 2‐diphenyl, 1‐picryl hydrazyl assay and anticancer activity against colon cancer (human colorectal adenocarcinoma cell line 29) compared with normal human embryonic kidney (HEK293) cells. Also, the prepared AgNPs were studied for its antibacterial activity. The AgNPs revealed a higher antioxidant activity compared with A. quttensis extract alone. The phyto‐synthesised AgNPs and A. quttensis extract showed a dose–response cytotoxicity effect against HT29 and HEK293 cells. As evidenced by Annexin V/propidium iodide staining, the number of apoptotic HT29 cells was significantly enhanced, following treatment with AgNPs as compared with untreated cells. Besides, the antibacterial property of the AgNPs indicated a significant effect against the selected pathogenic bacteria. These present obtained results show the potential applications of phyto‐synthesised AgNPs using A. quttensis aerial parts extract.Inspec keywords: nanoparticles, silver, nanomedicine, cancer, transmission electron microscopy, ultraviolet spectroscopy, visible spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, electrokinetic effects, kidney, cellular biophysics, antibacterial activity, toxicology, patient treatmentOther keywords: anticancer properties, antibacterial properties, antioxidant properties, phytosynthesised Artemisia quttensis Podlech extract mediated AgNP, ultraviolet‐visible spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, energy‐dispersive spectroscopy, dynamic light scattering, zeta‐potential analysis, antiradical scavenging activity, 2,2‐diphenyl, 1‐picryl hydrazyl assay, anticancer activity, HT29 colon cancer, human embryonic kidney cells, HEK293 cells, A. quttensis extract, dose‐response cytotoxicity effect, Annexin V staining, apoptotic HT29 cells, pathogenic bacteria, propidium iodide staining, Ag  相似文献   
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