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11.
Some historical glasses (lead-wood ash glasses, lead-crystal glasses…) are silicate glasses with high content of lead and potassium. This work presents the evaluation of the chemical stability of high-lead glasses in a high relative humidity atmosphere and as result of aqueous immersion. In both situations, the alteration mechanism begins with the lixiviation of alkali metal and lead ions, followed by the hydrolytic attack of the silica glass network. According to the results, the glasses with a higher content of lead show the fastest degradation due to their higher hygroscopicity. Environmental CO2 can be dissolved in the adsorbed water and favor the formation of intermediate degradation compounds.  相似文献   
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The development of wearable, all‐in‐one sensors that can simultaneously monitor several hazard conditions in a real‐time fashion imposes the emergent requirement for a smart and stretchable hazard avoidance sensing platform that is stretchable and skin‐like. Multifunctional sensors with these features are problematic and challenging to accomplish. In this context, a multimodal ferrofluid‐based triboelectric nanogenerator (FO‐TENG), featuring sensing capabilities to a variety of hazard stimulus such as a strong magnetic field, noise level, and falling or drowning is reported. The FO‐TENG consists of a deformable elastomer tube filled with a ferrofluid, as a triboelectric layer, surrounded by a patterned copper wire, as an electrode, endowing the FO‐TENG with excellent waterproof ability, conformability, and stretchability (up to 300%). In addition, The FO‐TENG is highly flexible and sustains structural integrity and detection capability under repetitive deformations, including bending and twisting. This FO‐TENG represents a smart multifaceted sensing platform that has a unique capacity in diverse applications including hazard preventive wearables, and remote healthcare monitoring.  相似文献   
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Optical fiber was modified with 3-(methacryloxy)propyltrimethoxysilane and copolymerized with the vinyl end groups and methacrylic to graft a thin layer of molecular imprinted polymer on the surface of the fiber without surface controlling. The modified fiber with phenol-imprinted polymer was coupled with gas chromatograph for headspace solid-phase microextraction (HS-SPME) of phenol. The extraction properties were examined using the SPME device coupled with a gas chromatograph–flame ionization detector (FID). Effects of extraction parameters, namely pH, exposure time, sampling temperature, and salt concentration, on extraction efficiency were also studied.  相似文献   
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This paper introduces a new speech cryptosystem, which is based on permutation and masking of speech segments using multiple secret keys in both time and transform domains. The main key is generated, randomly, using a Pseudo Noise (PN) sequence generator, and two other keys are generated from the main key to be used in the subsequent rounds of encryption. Either the Discrete Cosine Transform (DCT) or the Discrete Sine Transform (DST) can be used in the proposed cryptosystem to remove the residual intelligibility resulting from permutation and masking in the time domain. In the proposed cryptosystem, the permutation process is performed with circular shifts calculated from the key bits. The utilized mask is also generated from the secret key by circular shifts. The proposed cryptosystem has a low complexity, small delay, and high degree of security. Simulation results prove that the proposed cryptosystem is robust to the presence of noise.  相似文献   
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The predominant impediments to cutaneous wound regeneration are hemorrhage and bacterial infections that lead to extensive inflammation with lethal impact. We thus developed a series of composite sponges based on polyvinyl alcohol (PVA) inspired by marjoram essential oil and kaolin (PVA/marjoram/kaolin), adopting a freeze–thaw method to treat irregular wounds by thwarting lethal bleeding and microbial infections. Microstructure analyses manifested three-dimensional interconnected porous structures for PVA/marjoram/kaolin. Additionally, upon increasing marjoram and kaolin concentrations, the pore diameters of the sponges significantly increased, recording a maximum of 34 ± 5.8 µm for PVA-M0.5-K0.1. Moreover, the porosity and degradation properties of PVA/marjoram/kaolin sponges were markedly enhanced compared with the PVA sponge with high swelling capacity. Furthermore, the PVA/marjoram/kaolin sponges exerted exceptional antibacterial performance against Escherichia coli and Bacillus cereus, along with remarkable antioxidant properties. Moreover, PVA/marjoram/kaolin sponges demonstrated significant thrombogenicity, developing high thrombus mass and hemocompatibility, in addition to their remarkable safety toward fibroblast cells. Notably, this is the first study to our knowledge investigating the effectiveness of marjoram in a polymeric carrier for prospective functioning as a wound dressing. Collectively, the findings suggest the prospective usage of the PVA-M0.5-K0.1 sponge in wound healing for hemorrhage and bacterial infection control.  相似文献   
18.
The present work highlights how the constructal law is implemented in the search for buildings' performance from a thermal lookout. The authors reviewed some of their research efforts through two applications: radiant cooling panels and thermochemical energy storage in buildings. In a deterministic approach, it was demonstrated that the overall performance of such systems could be anticipated. Under the same operating conditions, cooling panel with dendritic flow configurations exhibited better global performance compared to the design with a serpentine flow layout. Two configurations of elemental reactors for thermochemical energy storage were studied: reactive material in beds layers and impregnated within a tube. A theoretical approach allowed to predict the impact of the Bejan number on the sensible heat output for the first configuration, when numerical experiments allowed to determine how to morph the tube shape to increase thermal performances.  相似文献   
19.
In this study, an efficient multistep synthesis of novel aromatic tricyclic hybrids incorporating different biological active moieties, such as 1,3,4-thiadiazole and 1,2,4-triazole, was reported. These target scaffolds are characterized by having terminal lipophilic or hydrophilic parts, and their structures are confirmed by different spectroscopic methods. Further, the cytotoxic activities of the newly synthesized compounds were evaluated using in vitro MTT cytotoxicity screening assay against three different cell lines, including HepG-2, MCF-7, and HCT-116, compared with the reference drug Taxol. The results showed variable performance against cancer cell lines, exhibiting MCF-7 and HepG-2 selectivities by active analogs. Among these derivatives, 1,2,4-triazoles 11 and 13 and 1,3,4-thiadiazole 18 were found to be the most potent compounds against MCF-7 and HepG-2 cancer cells. Moreover, structure–activity relationship (SAR) studies led to the identification of some potent LSD1 inhibitors. The tested compounds showed good LSD1 inhibitory activities, with an IC50 range of 0.04–1.5 μM. Compounds 27, 23, and 22 were found to be the most active analogs with IC50 values of 0.046, 0.065, and 0.074 μM, respectively. In addition, they exhibited prominent selectivity against a MAO target with apparent cancer cell apoptosis, resulting in DNA fragmentation. This research provides some new aromatic-centered 1,2,4-triazole-3-thione and 1,3,4-thiadiazole analogs as highly effective anticancer agents with good LSD1 target selectivity.  相似文献   
20.
Abstract: Highway engineers face complicated problems that are influenced by various conditions during the construction of flexible highway pavements. Identifying such problems and recommending effective solutions demand considerable engineering expertise, which is difficult to obtain at all construction sites. Thus, the development of an expert system can effectively help engineers control and analyze such problems. In addition, an expert system can effectively archive the storage and distribution of expertise among pavement engineers. This article describes the development and evaluation of such an expert system. The first stage in the development of the proposed system was the elicitation of knowledge from written sources and from experts through literature reviews and interviews, respectively. The acquired knowledge was analyzed and classified and then represented in a form containing rules; the rules were subsequently coded as software. This article describes the development and evaluation of the Expert System for the Control of Construction Problems in Flexible Highway Pavements.  相似文献   
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