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1.
Many occupations require workers to stand for long periods of time without proper interventions, which causes discomfort in the back and lower limbs. Therefore, this study aims to assess the effectiveness in alleviating body muscle discomfort during prolonged standing through the use of a calf massager. This study was conducted among male workers at a manufacturer with production line workers and the list was obtained from the HR Department and simple random sampling was done by number categorization. A total of 100 respondents (50 respondents for both the control and the experimental groups) participated in this study. The experiment took place in a room with a similar setup for the production line. Each respondent was requested to perform the simulated task for 2 hr. For the experimental group, the calf massager was turned on every 15 min. At every 15‐min interval after turning on the calf massager, respondents from both groups were required to evaluate their discomfort level on a Borg's scale CR‐10 questionnaire. The results showed that the level of body discomfort among respondents in the experimental group reduced (20–30%) compared with that of the control group. Multivariate analysis results revealed that the discomfort rating for the lower back, knees, thighs, calves, and feet was significantly lower (p < .05) among the experimental group compared with the control group. For lower body parts, the lower back region was statistically significant (p < .05) at the 90th, 105th, and 120th min; the thigh region was statistically significant (p < .05) at the 120th min; the knee region was statistically significant (p < .05) at the 105th and 120th min; the calf region was statistically significant (p < .05) at all minute intervals except the 15th and 45th min, while the feet region, was statistically significant at the 105th and 120th min. Therefore, this study indicates that calf massage treatment is capable of reducing body muscle discomfort during prolonged standing and highlights the significance of calf massage.  相似文献   
2.
The series of compounds La2–xSrxNiO4±y (0.0 x 1.0) crystallising in tetragonal K2NiF4 structure were prepared and catalytic activity have been investigated using isopropanol decomposition as model reaction. All the catalyst compositions catalyse only the dehydrogenation of isopropanol reaction. The composition La1.5Sr0.5NiO4 showed high activity compared to other compositions in the series. The composition is unique not only in catalytic property but also in other physical properties like structural characteristics, electrical resistivity and metal to semiconductor transition.  相似文献   
3.
Thin films of copper aluminum oxide (CuAlO2) were prepared on glass substrates by dc magnetron sputtering at a substrate temperature of 523 K under various oxygen partial pressures in the range 1 × 10−4–3 × 10−3 mbar. The dependence of cathode potential on the oxygen partial pressure was explained in terms of oxidation of the sputtering target. The influence of oxygen partial pressure on the structural, electrical and optical properties was systematically studied. p-Type CuAlO2 films with polycrystalline nature, electrical resistivity of 3.1 Ω cm, Hall mobility of 13.1 cm2 V−1 s−1 and optical band gap of 3.54 eV were obtained at an oxygen partial pressure of 6 × 10−4 mbar.  相似文献   
4.
During microbial enhanced oil recovery (MEOR) processes, the interaction between injection water (IW) and formation water (FW) salinity causes in-situ salinity variation which affects the final oil recovery. The present study explicitly quantifies the Original Oil in Place (OOIP) recovered for different IW and FW salinity conditions through numerical simulation. Based on simulation results, user-friendly empirical correlations were deduced to quickly estimate the OOIP. The results suggest that the OOIP increases drastically in all reservoirs with any initial FW salinity as the adopted salinity of IW is lowered. The study would serve as a tool for making reservoir management decisions.  相似文献   
5.
La0.7Ba0.3MnO3 (LBMO) thin films with different thicknesses were deposited on Si substrates using an electron beam evaporation technique for bolometer applications. To evaluate the influence of the thickness on their structural, compositional, morphological, and electrical properties, the LBMO thin films were characterized by x-ray diffraction (XRD), energy-dispersive spectroscopy, atomic force microscopy, and a four-probe method. XRD measurements showed that the crystal quality of the LBMO films improved with increasing thickness. The surface morphology revealed that the grain size and surface roughness of the films increased with increasing thickness. The resistivity increased with increasing thickness of the film. The temperature coefficient of resistance of the LBMO films decreased from 5.15%/K to 4.12%/K with increase of the film thickness from 20 nm to 100 nm.  相似文献   
6.
Nickel oxide (NiO) thin films were prepared on glass substrates at various bias voltages using dc reactive magnetron sputtering technique. The influence of substrate bias voltage on structural, optical and electrical properties was systematically investigated using X-ray diffraction (XRD), SEM, EDS, spectrophotometer and Hall effect studies. The NiO films are crystalline with preferential growth along (2 0 0) plane. The NiO films exhibit optical transmittance of 55% and direct band gap of 3.78 eV at the substrate bias voltage of −75 V. The electrical resistivity decreases as substrate bias voltage increases from 0 to −75 V thereafter it was slightly increased.  相似文献   
7.
CuCl residue is a hazardous waste from the hydrometallurgical zinc recovery plant. It is very difficult to recycle due to complicated composition, highly corrosive nature, and refractory characteristics. Recently, a new process of microwave drying and roasting was successfully developed to produce both CuO solid and HCl gas products from the CuCl residue. In this paper, the dielectric property of the CuCl residue was measured under different moisture contents. The microwave absorption characteristics of the CuCl residue improved considerably as its moisture content increased. Laboratory-scale drying tests were conducted to evaluate the kinetics of microwave drying and to optimize the operation parameters. The efficiency of microwave drying was further demonstrated in industrial-scale level by microwave dryer developed in in-house. Finally, the drying mechanism of microwave heating of the sticky material was discussed and several measurements were optimized/implemented to intensify the drying process.  相似文献   
8.
Sivasankar S  Chu S 《Nano letters》2007,7(10):3031-3034
A simple method is described to bond optical components using silica nanoparticle sol-gel chemistry. The silica nanoparticles polymerize into highly branched networks that link the surfaces together. The nanoparticle mediated bonding has several advantages to currently used optical joining technologies. The bonding is a room-temperature process and does not require any clean room facilities. The bonded interface has a high mechanical strength and low scattering. The bonding is resistant to organic solvents on silylation with hydrophobic surface groups. This method achieves 100% successful bonding rates between soda-lime glass slides. The bond-setting time can be tailored to allow time for precision optical alignment.  相似文献   
9.
Transparent and high conductive molybdenum doped indium oxide (IMO) thin films have been deposited on glass substrates by activated reactive evaporation. The effect of substrate temperature on the structure, surface morphology, electrical, optical and photoluminescence properties of these films were systematically examined and it was found that crystallinity and growth orientation of the films were significantly influenced by substrate temperature. In addition the films exhibited a low electrical resistivity of 5.2 × 10−4 Ω cm with an optical transmittance 90% in the visible region of the solar spectrum at a substrate temperature of 573 K. Intensive blue PL bands at 415 and 440 nm were observed in the photoluminescence spectrum at room temperature.  相似文献   
10.
Multimedia Tools and Applications - The Recommender System (RS) plays an important role in information retrieval techniques in a bid to handle massive online data effectively. It gives suggestions...  相似文献   
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