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61.
Various reactions take place between compounds of milk during heat treatment including denaturation and aggregation of whey proteins, and formation of new complexes. In this study, the antioxidant capacities of raw, pasteurised and sterilised milk were determined both before and after an enzymatic in vitro digestion process, using a radical cation decolorisation assay. The mean values of raw, pasteurised and sterilised milk before simulated digestion were 4.02, 4.47 and 4.18 mM trolox/g, respectively, and these did not differ significantly. The antioxidant capacity of all milk types increased significantly at the end of the simulated gastrointestinal digestion, being 11.13, 12.33, 11.88 mM trolox/g for raw, pasteurised and sterilised milk, respectively.  相似文献   
62.
Electrodeposition (ED) technique has been used to deposit thin-film cadmium telluride (CdTe) on glass-/fluorine-doped tin oxide substrates using a two-electrode system from acidic, aqueous medium containing Cd(NO3)2 4H2O, TeO2 and CdF2 as dopants. Photoelectrochemical cell measurement, DC conductivity measurement, X-ray diffraction, optical absorption, thickness measurement and atomic force microscopy were carried out to study the electrical, structural, optical, compositional and morphological properties of the as-grown, heat-treated and CdCl2-treated ED-CdTe layers, respectively. The characterization data obtained signified 1370 mV as the best growth potential and CdCl2 treatment at 400 °C for 15 min as the best post-growth treatment to achieve an optimal result.  相似文献   
63.
Adsorption and thermal desorption dynamics of acetone in fixed-bed silica gel were studied experimentally and theoretically. The effect of process factors on adsorption and desorption performances was established. Acetone adsorption from air stream was performed by the dynamic (flowing gas) method in a laboratory setup at two levels of air superficial velocity (0.7 and 1.7 cm s?1), temperature (30 and 40°C), and adsorbent particle diameter (0.21 and 0.54 cm). The values of saturation adsorption capacity (0.147–0.270 g g?1) increased up to 78% and 36%, respectively, with a decrease in air velocity and adsorption temperature. Acetone thermal desorption from spent silica gel was studied in a thermobalance at three levels of process temperature (60, 70, and 80°C) and two values of particle size (0.21 and 0.54 cm). Equilibrium desorption efficiency (63–81%) was up to 14% larger for finer particles and increased with the desorption temperature. Kinetic models with relevant parameters adjusted based on experimental data were adopted to predict the dynamics of acetone adsorption and thermal desorption. The models simulated well the real conditions and could be applied to scale up and operate the adsorption columns used for air remediation.  相似文献   
64.
This study compared the phenolic compositions of common green leafy vegetable extracts from Vernonia amygdalina (VA), Telfairia occidentalis (TO), Talinium triangulare (TT), and Amaranthus hybridus (AH) and their effects on the angiotensin-I-converting enzyme (ACE) and cisplatin-induced malonylaldehyde (MDA) production in an isolated rat kidney homogenate. HPLC confirmed the presence of phenolic compounds in the extracts. Furthermore, all extracts inhibited ACE activity dosedependently; however, the extract from VA exhibited the highest ACE activity while TT exhibited the least. Incubation of the kidney homogenate with 1mM cisplatin caused an increase in MDA production; however, all the extracts inhibited the level of MDA produced. Nevertheless, VA extract exhibited the highest inhibition. These activities of the vegetable extracts could be attributed to their phenolic compositions and may suggest some possible mechanism of the actions. However, VA appeared to be the most potent among the vegetables tested.  相似文献   
65.
Medicinal plants are widely utilised by the African population since they have no harmful side effects and low cost compared with different treatments. The field of nanotechnology is the most active part of research in modern material''s science. Though there are several chemicals as well as physical methods, however, green synthesis of nanomaterials is the most emerging method of synthesis. Conventionally, chemical reduction is the most often applied approach for the preparation of metallic nanoparticle''s however, in most of the synthesis protocols it cannot avoid the utilisation of toxic chemicals. Hence, the authors report an environmentally friendly, cost effective and green approach for synthesis of 1 mM AgNO3 solution using the polyphenolic‐rich leaf extracts of Syzygium cumini (S. cumini) (L.) Skeels as a reducing and capping agent. The synthesised AgNPs are characterised by UV‐Vis spectroscopy and Fourier transform infrared (FTIR) spectroscopy. FTIR analysis revealed that the AgNPs were stable due to eugenols, terpenes, and other different aromatic compounds present in the extract. The green biosynthesised S. cumini AgNPs significantly inhibited the growth of human pathogenic both gram‐positive Staphylococcus aureus (1.40 mm) and gram‐negative bacteria Escherichia coli (2.75 mm) and Salmonella typhimurium (1.45 mm) showing promising antimicrobial activity.Inspec keywords: silver, nanoparticles, nanofabrication, nanomedicine, antibacterial activity, biomedical materials, visible spectra, ultraviolet spectra, Fourier transform infrared spectra, microorganismsOther keywords: green‐route mediated synthesis, silver nanoparticles, Syzygium cumini, Skeels polyphenolic‐rich leaf extracts, antimicrobial activity, medicinal plants, African population, nanotechnology, physical methods, nanomaterials, metallic nanoparticles, AgNO3 solution, polyphenolic‐rich leaf extracts, capping agent, UV‐visible spectroscopy, Fourier transform infrared spectroscopy, FTIR, eugenols, terpenes, aromatic compounds, green biosynthesis, human pathogenic growth, gram‐positive Staphylococcus aureus, gram‐negative bacteria Escherichia coli, Salmonella typhimurium, antimicrobial activity, size 2.75 mm, size 1.45 mm, size 1.40 mm, Ag  相似文献   
66.
Peripheral artery disease (PAD) is characterized by impaired blood flow to the lower extremities, resulting in ischemic limb injuries. Individuals with diabetes and PAD typically have more severe ischemic limb injuries and limb amputations, but the mechanisms involved are poorly understood. Previously, we identified BAG3 as a gene within a mouse genetic locus termed limb salvage QTL1 on mouse chromosome 7 that determined the extent of limb necrosis following ischemic injury in C57Bl/6 mice. Whether BAG3 deficiency plays a role in the severe ischemic injury observed in diabetic PAD is not known. In vitro, we found simulated ischemia enhanced BAG3 expression in primary human skeletal muscle cells, whereas BAG3 knockdown increased necroptosis markers and decreased cell viability. In vivo, ischemic skeletal muscles from hind limbs of high-fat diet (HFD)-fed mice showed poor BAG3 expression compared to normal chow diet (NCD)-fed mice, and this was associated with increased limb amputations. BAG3 overexpression in ischemic skeletal muscles from hind limbs of HFD mice rescued limb amputation and improved autophagy, necroptosis, skeletal muscle function and regeneration. Therefore, BAG3 deficiency in ischemic skeletal muscles contributes to the severity of ischemic limb injury in diabetic PAD, likely through autophagy and necroptosis pathways.  相似文献   
67.
The required steam for steam-assisted gravity drainage (SAGD) oil sands operations is generated using a once-through steam generator (OTSG) that is fed with relatively poor quality process water. Industries have reported possible solid particle erosion-related failure in the OTSG boiler tubes because of the transport of precipitated dense inorganic particles. However, the presence of other damage mechanisms, e.g. corrosion, flow accelerated corrosion (FAC), often masks the evidence of erosive wear. Also, industries set an upper limit operating velocity for the OTSG using the API RP 14E guideline, which provides no quantitative erosion rates to determine an operating envelope. This study presents a computational fluid dynamics (CFD) analysis of erosion damage in a SAGD OTSG boiler tube. The results revealed that API RP 14E may not be an effective decision-making tool for operating the OTSG system. For example, a 10% increase in velocity, even at conditions below the API RP 14E threshold, showed a decrease in the failure time of the boiler tubes by 40%–50%.  相似文献   
68.
Silicon - This research evaluated the ternary blend of agricultural waste in cow bone ash, industrial waste glass powder and cement in improving the Geotechnical properties of tropical lateritic...  相似文献   
69.
The development of an effective powder utilization is key to maximizing the potential of polyamide 12 (PA 12) for commercial laser-based powder bed fusion of polymers (PBF-LB/P). This requires an extensive study of relationships between the powder reuse extent, macroscopic properties of the powder, and mechanical properties of sintered parts. This work investigates the effects of the extent of PA 12 powder reuse during PBF-LB/P on the powder's degradation degree and mechanical properties of the sintered parts. Powder reuse extent was expressed in terms of cumulative build time while degradation degree was assessed in terms of deviations in the properties of the reused powders from those of virgin powder. Increase in the powder reuse extent led to increased thickness of crystallite, melting temperature, and sintering window of the powder while the crystallization temperature, crystallinity degree, and melt flow rate decreased with increased reuse extent. The mechanical strength and modulus of the sintered parts initially decreased with an increase in number of build cycles to reach a minimum at the sixth build cycle, after which it increased. This study is a step further towards achieving an efficient PA 12 powder management and a systematic control of quality of sintered parts.  相似文献   
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