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排序方式: 共有278条查询结果,搜索用时 171 毫秒
1.
Situated within a critical, feminist approach to development communication, this study examines the role of television advertising among unskilled female factory laborers in Bangalore, India. Ethnographic fieldwork spanning the summers of 1997 and 2000 showed that factory labor awards the female worker a degree of autonomy and purchasing power in the short term, but denies her long-term empowerment because her labor is fragmented and made dispensable by the very nature of capitalist discipline. Through a discussion of gender, labor, and television in the global city, the analysis concludes that participatory communication and further ethnographic analyses are essential for long-lasting policy and social action.  相似文献   
2.
In real world, the automatic detection of liver disease is a challenging problem among medical practitioners. The intent of this work is to propose an intelligent hybrid approach for the diagnosis of hepatitis disease. The diagnosis is performed with the combination of k‐means clustering and improved ensemble‐driven learning. To avoid clinical experience and to reduce the evaluation time, ensemble learning is deployed, which constructs a set of hypotheses by using multiple learners to solve a liver disease problem. The performance analysis of the proposed integrated hybrid system is compared in terms of accuracy, true positive rate, precision, f‐measure, kappa statistic, mean absolute error, and root mean squared error. Simulation results showed that the enhanced k‐means clustering and improved ensemble learning with enhanced adaptive boosting, bagged decision tree, and J48 decision tree‐based intelligent hybrid approach achieved better prediction outcomes than other existing individual and integrated methods.  相似文献   
3.
Suresha  B.  Divya  G. S.  Hemanth  G.  Somashekar  H. M. 《SILICON》2021,13(7):2319-2335
Silicon - This research article describes the results of nano-silica (nSiO2) filled epoxy (Ep) mono composites with different contents (0.5, 1.0, 1.5, 3, and 5 wt.%) and carbon...  相似文献   
4.
Formation of spinel phases in ZnO–Sb2O3and ZnO–Sb2O3–Bi2O3systems is studied by the use of X-ray diffraction. The formation of nonstoichiometric Zn2.33Sb0.67O4phase is observed in both the systems at ∼900°C. However, in these systems, at higher temperatures ( T ≥ 1100°C), formation of the inverse spinel phase Zn7Sb2O12is observed. The study has been extended to understand the effect of CrO3doping on the stability of the different spinel phases in the previously mentioned systems. Interestingly, in both the systems, samples doped with CrO3, displayed the presence of Zn2.33Sb0.67O4phase <1200°C, indicating the stabilization of the spinel phase by CrO3.  相似文献   
5.
Synthesis of Biodiesel from Canola Oil Using Heterogeneous Base Catalyst   总被引:1,自引:0,他引:1  
A series of alkali metal (Li, Na, K) promoted alkali earth oxides (CaO, BaO, MgO), as well as K2CO3 supported on alumina (Al2O3), were prepared and used as catalysts for transesterification of canola oil with methanol. Four catalysts such as K2CO3/Al2O3 and alkali metal (Li, Na, K) promoted BaO were effective for transesterification with >85 wt% of methyl esters. ICP-MS analysis revealed that leaching of barium in ester phase was too high (~1,000 ppm) when BaO based catalysts were used. As barium is highly toxic, these catalysts were not used further for transesterification of canola oil. Optimization of reaction conditions such as molar ratio of alcohol to oil (6:1–12:1), reaction temperature (40–60 °C) and catalyst loading (1–3 wt%) was performed for most efficient and environmentally friendly K2CO3/Al2O3 catalyst to maximize ester yield using response surface methodology (RSM). The RSM suggested that a molar ratio of alcohol to oil 11.48:1, a reaction temperature of 60 °C, and catalyst loading 3.16 wt% were optimum for the production of ester from canola oil. The predicted value of ester yield was 96.3 wt% in 2 h, which was in agreement with the experimental results within 1.28%.  相似文献   
6.
ABSTRACT

Ozone processing is one of the encouraging non-thermal and bio-friendly techniques in the food processing sector. The applicability of ozone technology in food industry is increasing due to its antimicrobial action and modification of functional properties of the foods. The structural modifications of starches have major applications in the food and bakery industry for producing products with increased shelf life, improved texture, and retention of moisture content. The positive response of ozonation in carboxyl and carbonyl group alters the viscosity of starch molecules. Rheological characteristics like low viscosity even at an increased concentration, desirable binding properties, and film-forming ability have increased its use in the food processing industry. The influence of ozonation in the physicochemical properties is mainly retrogradation and cross-linking of amylose and amylopectin molecules and enzymatic modifications. Ozonation cause change in crystallinity, viscosity, expansion ratio, and gelatinization temperatures. Finally, ozonation induces many possible changes in native starches for the effective utilization in the processing sectors. In this review, starch modifications utilizing ozone and various research achievements and scientific reports focusing on the effect of ozonation in terms of physical, chemical, and thermal properties of native starches and on the possible modifications have been summarized and discussed. In conclusion, ozone is a green technology that can be effectively used as an alternative oxidation technique for starch modification.  相似文献   
7.
Evans  Michael G.  Al-Shakli  Arwa  Jenkins  Stuart I.  Chari  Divya M. 《Nano Research》2017,10(8):2881-2890
The development of safe technologies to genetically modify neurons is of great interest in regenerative neurology,for both translational and basic science applications.Such approaches have conventionally been heavily reliant on viral transduction methods,which have safety and production limitations.Magnetofection (magnet-assisted gene transfer using iron oxide nanoparticles as vectors) has emerged as a highly promising non-viral alternative for safe and reproducible genetic modification of neurons.Despite the high potential of this technology,there is an important gap in our knowledge of the safety of this approach,namely,whether it alters neuronal function in adverse ways,such as by altering neuronal excitability and signaling.We have investigated the effects of magnetofection in primary cortical neurons by examining neuronal excitability using the whole cell patch clamp technique.We found no evidence that magnetofection alters the voltage-dependent sodium and potassium ionic currents that underpin excitability.Our study provides important new data supporting magnetofection as a safe technology for bioengineering of neuronal cell populations.  相似文献   
8.
This paper reports the sensing response characteristics of rf-sputtered SnO2 thin films (90 nm thick) loaded with platinum catalyst cluster of varying thickness (2-20 nm) for LPG detection. The enhanced response (5 × 103) was obtained for 200 ppm LPG with the presence of 10 nm thin and uniformly distributed Pt catalyst clusters on the surface of SnO2 thin film at a relatively low operating temperature (220 °C). The high response for LPG is shown to be primarily due to the enhanced catalytic activity for adsorbed oxygen on the surface of SnO2 thin film besides the spill over mechanism at elevated temperature.  相似文献   
9.
ECAP is an effective process to improve the mechanical strength and wear resistance along with mechanical and microstructural properties. AA2014 solutionized at 495 °C and aged at 195 °C was subjected to Equal Channel Angular Pressed (ECAP) through route A and Bc at room temperature. It was well proved that the mechanical strength increased due to ECAP in AA2014. In order to investigate their wear behavior after ECAP, dry sliding wear tests were conducted using vacuum tribometer at nominal loads of 10N and 30N with constant speed of 2 m/s for sliding distance of 2000 m. The co-efficient of friction and loss in volume were decreased after ECAP both in route A and Bc. The dominant wear mechanisms observed were adhesive, delamination and stick slip process. In addition to these wear mechanisms, abrasive wear also appeared along with transfer of iron particles from the counter surface to the AA2014 pin. Presence of black powder and oxide formation were observed using EDAX analysis on wear debris. Routes A and Bc showed similar wear mechanisms and characteristics which were better than in unECAPed specimens.  相似文献   
10.
Multimedia Tools and Applications - Images are widely accepted as a record of events even when images are prone to easy manipulations. It is difficult to identify image alterations by the human...  相似文献   
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