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排序方式: 共有356条查询结果,搜索用时 281 毫秒
51.
This paper presents initial information on the development and validation of three team task analysis scales. These scales were designed to quantitatively assess the extent to which a group of tasks or a job is team based. During a 2-week period, 52 male students working in 4-person teams were trained to perform a complex highly interdependent computer-simulated combat mission consisting of both individual- and team-based tasks. Our results indicated that the scales demonstrated high levels of interrater agreement. In addition, the scales differentiated between tasks that were predetermined to be individual versus team based. Finally, the results indicated that job-level ratings of team workflow were more strongly related to team performance than were aggregated task-level ratings of team-relatedness or team workflow. These results suggest that the scales presented here are an effective means of quantifying the extent to which tasks or jobs are team based. A research and practical implication of our findings is that the team task analysis scales could serve as criterion measures in the evaluation of team training interventions or predictors of team performance. 相似文献
52.
Vasanth Winston X. Sankar D. SenthilKannan K. Vimalan M. Rajesh Kumar T. 《Journal of Materials Science: Materials in Electronics》2022,33(26):20616-20630
Journal of Materials Science: Materials in Electronics - Nonlinear optical organometallic single crystal of manganese mercury thiocyanate (MMTC) has been grown by SR method in aqueous solution. The... 相似文献
53.
Ravishankar Sathyamurthy Abd Elnaby Kabeel El‐Sayed El‐Agouz DSilva Rufus Hitesh Panchal Thirugnanasambantham Arunkumar Athikesavan Muthu Manokar David Gnanaraj Prince Winston 《国际能源研究杂志》2019,43(8):3295-3305
This work aims at augmenting the amount of potable water using MgO and TiO2 in stepped solar still. Experiments were carried out for the climatic conditions of Chennai, India, with two different concentrations of nanofluids inside a stepped basin under three different cases. Results show that there is an improvement in yield of fresh water from stepped solar still by 33.18% and 41.05% using 0.1% and 0.2% volume concentration of TiO2 nanofluid, respectively, whereas the freshwater yield from stepped still with MgO nanofluids improved by 51.7% and 61.89%. Furthermore, the economic analysis revealed that the cost of potable water from the modified solar still reduced from 0.029 to 0.016 $/kg. Similarly, the useful annual energy, yearly cost per kilogram, and annual cost per kilowatt hour are significantly profitable with the use of MgO nanofluid in the stepped basin and found as 512.46 kWh, 0.025 $/kg, and 0.026 $/kWh, respectively. It is also found that the cost of potable water from the modified still significantly increases as the amount of fresh water produced is decreased with increased fabrication cost of the solar still. 相似文献
54.
Dechao Chen Shoucong Ning Jiao Lan Ming Peng Huigao Duan Anlian Pan Yongwen Tan 《Advanced materials (Deerfield Beach, Fla.)》2020,32(46):2004055
Although 2D layered metal compounds are widely exploited using various techniques such as exfoliation and vapor-phase-assisted growth, it is still challenging to construct the 2D materials in a 3D configuration with preservation of the unique physicochemical properties of the metal compounds. Herein, a general synthetic strategy is reported for a wide variety of 2D (atomic-scale thickness) metal compounds with 3D bicontinous nanoporous structure. 19 binary compounds including sulfides, selenides, tellurides, carbides, and nitrides, and five alloyed compounds, are successfully prepared via a surface alloy strategy, which are readily created by using a recyclable nanoporous gold assisted chemical vapor deposition process. These 3D nanoporous metal compounds with preserved 2D physicochemical properties, tunable pore sizes, and compositions for electrocatalytic applications, show excellent catalytic performance in the electrochemical N2 reduction reaction. This work opens up a promising avenue for fundamental studies and potential applications of a wide variety of nanoporous metal compounds. 相似文献
55.
Guanhua Zhang Jin Hu Yan Nie Yanli Zhao Lei Wang Yizhou Li Huaizhi Liu Lizhen Tang Xianan Zhang Du Li Ling Sun Huigao Duan 《Advanced functional materials》2021,31(24):2100290
Flexible and lightweight supercapacitors with superior mechanical flexibility and outstanding capacity are regarded as an ideal power source for wearable electronic devices. Meanwhile, incorporating additional novel characters such as transparency and electrochromism can further benefit the development of smart supercapacitors. Nevertheless, the application of the commonly used planar-structural current collectors is seriously restricted by their intrinsic properties such as poor rigidity, large thickness, and limited loading surface area. Flexible and ultralight current collectors with 3D architecture, high conductivity, and easy integration are believed to be the most appropriate alternatives to build high-performance supercapacitors. In this study, a novel and scalable manufacturing technique is developed to produce a flexible and ultralight 3D Ni micromesh (3D NM) current collector for supercapacitor. Flexible smart supercapacitor integrated by 3D NM and high active Ni–Co bimetallic hydroxide (3D NM@NiCo BH) delivers a considerable rate performance (60.6% capacity retention from 1 to 50 mA cm−2). Furthermore, the fabricated hybrid supercapacitor device integrated with electrochromic functionality can visually indicate the energy level by a color display. This flexible electrochromic supercapacitor based on ultralight 3D Ni micromesh provides a novel insight into multifunctional energy storage systems for smart wearable electronic devices. 相似文献
56.
Huaizhi Liu Jinhao Li Xianan Zhang Xiuxue Liu Yu Yan Fengjun Chen Guanhua Zhang Huigao Duan 《Advanced functional materials》2021,31(48):2106550
Ultraflexible and ultralight rechargeable aqueous Zn-ion batteries (ZIBs) with the merits of environmental benignity and high security arise as promising candidates for flexible electronic systems. Nowadays, the energy density and cyclical stability of ZIBs on metal-based rigid substrates reach a satisfactory level, while the inflexible substrates severely prevent them from widespread commercial adoption in portable electronics. Although flexible substrates-engineered devices burgeon, the development of flexible ZIBs with high specific energy still faces great challenges. Herein, a flexible ultrathin and ultralight Zn micromesh (thickness of 8 µm and areal density of 4.9 mg cm−2) with regularly aligned microholes is fabricated via combining photolithography with electrochemical machining. The unique microholes-engineered Zn micromesh presents excellent flexibility, enhanced mechanical strength, and better wettability. Moreover, numerical simulations in COMSOL and in situ microscopic observation system certify the induced spatial-selection deposition of Zn micromesh. Accordingly, aqueous ZIBs constructed with polyaniline-intercalated vanadium oxide cathode and Zn micromesh anode demonstrate exceptional high-rate capability (67.6% retention with 100 times current density expansion) and cyclical stability (maintaining 87.6% after 1000 cycles at 10.0 A g−1). Furthermore, the assembled pouch cell displays superb flexibility and durability under different scenarios, indicating great prospects in high-energy ZIBs and flexible electronics. 相似文献
57.
Oladapo A. Afolabi Mobolaji E. Aluko Gino C. Wang Winston A. Anderson Folahan O. Ayorinde 《Journal of the American Oil Chemists' Society》1989,66(7):983-985
This paper examines the synthesis of a toughened elastomer fromVernonia galamensis seed oil by reacting vernonia oil with vernonia oil-derived suberic acid (octanedioic acid), and cross-linking the pre-polymer
in the immediate presence of cross-linked polystyrene preparedin situ. The paper also demonstrates that the progress of reaction can be followed by monitoring the generation of hydroxyl groups
using infrared spectroscopy. Analysis of some crystalline material on the cooler parts of the reaction vessels revealed the
presence of component fatty acids of vernonia oil. Transmission electron microscopy characterization of the synthesized toughened
elastomer suggests that vernonia oil-suberic acid polyester and polystyrene polymer are interpenetrating. 相似文献
58.
Formation process of core‐shell microparticles by solute migration during drying of homogenous composite droplets 下载免费PDF全文
Nan Fu Winston Duo Wu Zhangxiong Wu Fei Tzhung Moo Meng Wai Woo Cordelia Selomulya Xiao Dong Chen 《American Institute of Chemical Engineers》2017,63(8):3297-3310
Particle formation process during spray drying profoundly impacts particle morphology and microstructure. This study experimentally investigated the formation of core‐shell‐structured microparticles by one‐step drying of composite droplets made of Eudragit® RS (a polycationic acrylic polymer in nanoparticle form) and silica sol. The formation of an incipient surface shell was monitored using single droplet drying technique, and the freshly formed shell was recovered for subsequent analyses. Adding silica to RS precursor increased the shell formation time and altered the properties of the incipient shell from water‐dispersible to nondispersible. The incipient shell formed from RS/silica droplets with mass ratios of 1.5%:1.5% and 0.5%:2.5% showed ingredient segregation with a preferential accumulation of RS, similar to the shell region of dried microparticles. After shell formation, excess silica sol in the liquid phase could flow inward, producing a dense core. This mobility‐governed solute migration would be useful for constructing core‐shell microparticles using other precursor systems. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3297–3310, 2017 相似文献
59.
Pierre‐Marie Nigay Ange Nzihou Claire E. White Winston O. Soboyejo 《Journal of the American Ceramic Society》2017,100(10):4748-4759
In this paper, the structure‐property relationships of a clay ceramic with organic additives (biomass and biochar) are investigated to develop an alternative material for thermal energy storage. The firing transformations were elucidated using X‐ray pair distribution function analysis, differential scanning calorimetry, and scanning electron microscopy. It was found that the biomass increased the porosity, which resulted in a decrease of the specific heat capacity. On the other hand, the biochar remained in the clay ceramic without any interaction with the clay matrix up to 950°C. The specific heat capacity of the clay ceramic increased from 1.20 to 1.49 kJ/kg·K for a 30 wt% addition of biochar. The clay ceramic with a 30 wt% addition of biochar also conserved a high flexural strength of 11.1 MPa compared to that of the clay ceramic without organic additives (i.e., 18.9 MPa). Furthermore, the flexural strength only decreased by 23% after 100 thermal cycles. The crack growth associated with the thermal fatigue was limited by crack bridging and crack trapping. Hence, the current results suggest that clay/biochar ceramics can be as efficient as molten salts in thermal energy storage with the added benefit of an ease of use in the physical form of bricks. 相似文献
60.
A. Muthu Manokar M. Vimala D. Prince Winston D. R. Rajendran Ravishankar Sathyamurthy A. E. Kabeel 《亚洲传热研究》2020,49(8):4394-4409
In this paper, an experimental study of the conventional solar still (CSS), the conventional solar still with glass cooling (CSSGC), the conventional solar still with basin heating (CSSBH), and the conventional solar still with glass cooling and basin heating (CSSGCBH) was carried out on the basis of the distilled water production, the energy efficiency (EnE), the exergy efficiency (ExE), and economic analysis. The CSSGC and CSSBH contain Peltier modules for cooling the glass and heating the basin. The evaporative heat transfer coefficient for all the experimental stills was calculated. The values of daily distilled water production from the CSSGCBH, CSSBH, CSSGC, and CSS were 4.56, 3.79, 2.49, and 1.89 kg/m2, respectively. The daily distilled yield of the CSSBH and CSSGCBH were increased by 58.55% and 50.13%, respectively, as compared with the CSS. Moreover, the daily EnE and ExE of the CSSGCBH were 27.03% and 3.5%, respectively, whereas the EnE and ExE of the CSS were 10.88% and 1.3%, respectively. Furthermore, the cost of distilled water production was found to be 0.26, 0.35, 0.53, and 0.64 $/day for the CSS, CSSGC, CSSBH, and CSSGCBH, respectively, if the selling price of the distilled water was Rs10. 相似文献