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31.
Plasma spraying is one of the potential manufacturing technologies widely used in tubular solid oxide fuel cells (SOFC) fabrication. The plasma spray technology requires powders with good flowability and large particle size (5-200 μm). A simple, low temperature assisted chemical process was used for the preparation of plasma grade yttria stabilized zirconia powder without any agglomeration process. The powder was characterized by X-ray diffractometry, particle size analysis, scanning electron microscopy and Raman spectroscopy. The powder exhibited cubic phase, good flowability and blocky angular shape. The 8YSZ powder was plasma sprayed and the coatings after sintering showed gas tightness (gas leak rate ∼ 1 × 10−6 mbar l s−1 cm2). This was substantiated by the presence of densely packed grains as seen in the surface FESEM image of the sintered plasma sprayed 8YSZ free form. Conductivity values in par with the values reported in literature were obtained for plasma sprayed 8YSZ coating.  相似文献   
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BACKGROUND : Propionic acid is widely used in chemical and allied industries and can be produced by biocultivation in a clean and environmentally friendly route. Recovery of the acid from the dilute stream from the bioreactor is an economic problem. Reactive extraction is a promising method of recovering the acid but suffers from toxicity problems of the solvent employed. There is thus a need for a non‐toxic solvent or a combination of less toxic extractants in a non‐toxic diluent that can recover acid efficiently. RESULTS: The effect of different extractants (tri‐n‐butylphosphate (TBP), tri‐n‐octylamine (TOA) and Aliquat 336) and their mixed binary solutions in sunflower oil diluent was studied to find the best extractant‐sunflower oil combination. Equilibrium complexation constant, KE, values of 4.02, 3.13 and 1.87 m3 kmol?1 were obtained for propionic acid extraction using Aliquat 336, TOA and TBP, respectively, in sunflower oil. The effect of different modifiers (1‐decanol, methylisobutyl ketone, butyl acetate and dodecanol) on the extraction was also studied and it was found that modifiers enhance extraction, with 1‐decanol found to be the best. CONCLUSION: The problem of toxicity in reactive extraction can be reduced by using a non‐toxic diluent (sunflower oil) or a modifier in a non‐toxic solvent, with the extractant. The addition of modifiers was found to improve the extraction. Copyright © 2008 Society of Chemical Industry  相似文献   
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This paper reports the characteristics and performance evaluation of a pressed plastic bonded explosive (PBX) composition based on hexanitrohexaazaisowurtzitane (HNIW, CL‐20) and polyurethane (PU) in comparison with PU‐coated cyclotetramethylene tetranitramine (HMX). PU‐coated compositions were prepared by slurry method. The processed CL‐20‐based composition exhibited a relatively higher sensitivity compared to that of the HMX composition. The measured velocity of detonation (VOD) of the CL‐20‐based composition was found to be higher than predicted. A theoretical approach was applied to assess the penetration capability of the CL‐20 formulation. Shaped charges of 32 mm caliber were prepared and penetration experiments were carried out at 37 mm standoff distance on mild steel blocks. The results established high penetration capability of CL‐20‐based formulation. An attempt was made to explain the trends obtained.  相似文献   
34.
Intratracheal administration of the anticancer drug bleomycin to hamsters produced an increase in the uptake and incorporation of [14C] choline into phospholipids of lung slicesin vitro. The stimulatory effect is opposite to the results obtained previously using [14C] acetate and would appear to occur distal to cytidine diphosphocholine. Although alternate explanations are possible, the results are consistent with morphological evidence, published by others, indicating an increase in lung phospholipid following bleomycin treatment, and illustrate the significance of precursor selection when evaluating the effects of xenobiotics on phospholipid synthesis.  相似文献   
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Recent epidemiological studies have shown a relationship between swimming in recreational waters meeting bacteriological standards and gastroenteritis with a suggested viral etiology. No previous studies have been conducted in the United States on the occurrence of human pathogenic enteric viruses in freshwater recreational areas. The presence of enteroviruses and rotaviruses was investigated in Oak Creek, Arizona, a heavily used recreational area. Water samples were filtered through positively charged filters (168–1555 I.), eluted with beef extract, and assayed for human enteroviruses and rotaviruses. Eighteen of the 41 recreational water samples were positive for enterovirus or rotavirus. Of these, nine samples exceeded the Arizona State recommended limit of 1 PFU 40 l−1 for full body contact in effluent dominated recreational waters. Several virus positive samples met the recommended fecal coliform standards (200 CFU 100 ml−1) for recreational waters indicating the inadequacy of bacterial standards for monitoring viral water quality. The isolation of the pathogenic enteric viruses (i.e., poliovirus 1, echovirus 1, coxsackievirus B1 and B6 and rotavirus) from this popular recreational water demonstrates the potential for transmission of viral disease.  相似文献   
37.
With the emergence of the Internet of things (IoT), embedded systems have now changed its dimensionality and it is applied in various domains such as healthcare, home automation and mainly Industry 4.0. These Embedded IoT devices are mostly battery-driven. It has been analyzed that usage of Dynamic Random-Access Memory (DRAM) centered core memory is considered the most significant source of high energy utility in Embedded IoT devices. For achieving the low power consumption in these devices, Non-volatile memory (NVM) devices such as Parameter Random Access Memory (PRAM) and Spin-Transfer Torque Magnetic Random-Access Memory (STT-RAM) are becoming popular among main memory alternatives in embedded IoT devices because of their features such as high thickness, byte addressability, high scalability and low power intake. Additionally, Non-volatile Random-Access Memory (NVRAM) is widely adopted to save the data in the embedded IoT devices. NVM, flash memories have a limited lifetime, so it is mandatory to adopt intelligent optimization in managing the NVRAM-based embedded devices using an intelligent controller while considering the endurance issue. To address this challenge, the paper proposes a powerful, lightweight machine learning-based workload-adaptive write schemes of the NVRAM, which can increase the lifetime and reduce the energy consumption of the processors. The proposed system consists of three phases like Workload Characterization, Intelligent Compression and Memory Allocators. These phases are used for distributing the write-cycles to NVRAM, following the energy-time consumption and number of data bytes. The extensive experimentations are carried out using the IoMT (Internet of Medical things) benchmark in which the different endurance factors such as application delay, energy and write-time factors were evaluated and compared with the different existing algorithms.  相似文献   
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The effects of five different biomass species and their chemical composition on the overall process efficiency and economic performance considering feedstock availability and feedstock costs to manufacture ethanol from lignocellulose were studied. First is a comparison of ethanol production and excess electricity generated between different biomass species. Results show that, at the same feedstock rate of 2000 Mg day?1, aspen wood has larger ethanol production than switchgrass, hybrid poplar and corn stover, while the excess electricity generated is as follows in increasing order: aspen < corn stover < hybrid poplar/switchgrass. Second, our results show that the ethanol production is largely linear with holocellulose (cellulose plus hemicellulose) composition of the various biomass species. However, the relationship between excess electricity generated and non-holocellulose combustible component is nonlinear. Last, on environmental performance, it is found that the water losses per unit ethanol production are in the following order: aspen wood < corn stover < hybrid poplar < switchgrass. While corn stover is a potential feedstock to produce cellulosic ethanol with the lowest ethanol production cost at the present time, hybrid poplar and switchgrass are the two promising future energy crops.The effects of plant size analysis showed that the estimated feedstock delivered costs, ethanol production, excess electricity generated and solid and gaseous waste emissions all increase with plant size for the various biomass species. The ethanol production costs decrease with the increase in plant size with optimal plant sizes for corn stover in the range from 2000 dry Mg day?1 to 4000 dry Mg day?1.  相似文献   
40.
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