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1.
Zenan Yu Julian Moore Jean Calderon Lei Zhai Jayan Thomas 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(39):5289-5295
Cable‐shaped supercapacitors (SCs) have recently aroused significant attention due to their attractive properties such as small size, lightweight, and bendability. Current cable‐shaped SCs have symmetric device configuration. However, if an asymmetric design is used in cable‐shaped supercapacitors, they would become more attractive due to broader cell operation voltages, which results in higher energy densities. Here, a novel coil‐type asymmetric supercapacitor electrical cable (CASEC) is reported with enhanced cell operation voltage and extraordinary mechanical‐electrochemical stability. The CASECs show excellent charge–discharge profiles, extraordinary rate capability (95.4%), high energy density (0.85 mWh cm−3), remarkable flexibility and bendability, and superior bending cycle stability (≈93.0% after 4000 cycles at different bending states). In addition, the CASECs not only exhibit the capability to store energy but also to transmit electricity simultaneously and independently. The integrated electrical conduction and storage capability of CASECS offer many potential applications in solar energy storage and electronic gadgets. 相似文献
2.
A first‐principles‐based effective Hamiltonian is developed and employed to investigate finite‐temperature structural properties of a prototype of perovskite halides, that is CsPbI3. Such simulations, when using first‐principles‐extracted coefficients, successfully reproduce the existence of an orthorhombic Pnma state and its iodine octahedral tilting angles around room temperature. However, they also yield a direct transformation from Pnma to cubic upon heating, unlike measurements that reported the occurrence of an intermediate long‐range‐tilted tetragonal P4/mbm phase in‐between the orthorhombic and cubic phases. Such disagreement, which may cast some doubts about the extent to which first‐principle methods can be trusted to mimic hybrid perovskites, can be resolved by “only” changing one short‐range tilting parameter in the whole set of effective Hamiltonian coefficients. In such a case, some reasonable values of this specific parameter result in the predictions that i) the intermediate P4/mbm state originates from fluctuations over many different tilted states; and ii) the cubic phase is highly locally distorted and develops strong transverse antiphase correlation between first‐nearest neighbor iodine octahedral tiltings, before undergoing a phase transition to P4/mbm under cooling. 相似文献
3.
M. R. Thompson 《Drug development and industrial pharmacy》2015,41(8):1223-1231
Twin screw granulation (TSG) is a new process of interest to the pharmaceutical community that can continuously wet granulate powders, doing so at lower liquid concentrations and with better product consistency than found by a high shear batch mixer. A considerable body of research has evolved over the short time since this process was introduced but generally with little comparison of results. A certain degree of confidence has been developed through these studies related to how process variables and many attributes of machinery configuration will affect granulation but some major challenges still lay ahead related to scalability, variations in the processing regimes related to degree of channel fill and the impact of wetting and granulation of complex powder formulations. This review examines the current literature for wet granulation processes studied in twin screw extrusion machinery, summarizing the influences of operational and system parameters affecting granule properties as well as strives to provide some practical observations to newly interested users of the technique. 相似文献
4.
通过制备不同晶相结构〔单斜相(m-ZrO_2)、四方相(t-ZrO_2)和无定型(a-ZrO_2)〕ZrO_2载体,再通过沉积沉淀法制得Cu/m-ZrO_2、Cu/t-ZrO_2和Cu/a-ZrO_2催化剂,分别用于催化二乙醇胺脱氢合成亚氨基二乙酸反应。采用XRD、氮气物理吸附脱附、XPS、H_2-TPR、CO_2-TPD对催化剂的结构进行了表征。结果表明,Cu/m-ZrO_2催化剂界面更加有利于Cu~+/Cu~0稳定存在,具有更多的碱性位点,且抗氧化性较好。在二乙醇胺脱氢反应中,Cu/m-ZrO_2催化剂性能最好,反应时间为2.5 h,亚氨基二乙酸收率为97.64%。 相似文献
5.
《Ceramics International》2020,46(5):6129-6135
The design of functional anti-wetting ceramic coatings is always a bottleneck restricting the development of ceramic techniques. This study proposes a liquid phase synthesis method to fabricate α-Fe2O3 (III) ceramic powders with promising applications and introduces a facile electrophoretic deposition (EPD) technique to construct the corresponding functionalized hydrophobic films – superhydrophobic functionalized α-Fe2O3 ceramic films (SFOFS) with roughly even distribution and a high water contact angle (CA) of 169°±1° – followed by heat posttreatments. The microtopography and crystalline structures of the product were investigated by FESEM, EDX, and XRD techniques. The EPD controllability of SFOFS was studied by adjusting the EPD time and the applied field strengths. In addition, the SFOFS show excellent long-term anti-wetting properties for twenty-four months after undergoing a series of tests, including soaking, water droplet impacting, immersion by droplets with different surface tensions and exposure to different gases and relative humidity conditions, etc. This study substantially helps the design of other kinds of functional anti-wetting films through the proposed convenient method beyond the oxide limit. 相似文献
6.
《Displays》2015
Modern liquid crystal displays (LCDs) require novel technologies, such as new alignment methods to eliminate alignment layers, fast response and long operation time. To this end, we report an overview of recent efforts in LCD technologies devoted to realize more display modes having no alignment layer, faster switching time and low battery consumption. In particular, we overview recent advances on the liquid crystals (LCs) alignment for display applications, which includes superfine nanostructures, polymeric microchannels and polymer stabilized LCs. Furthermore, we analyze the main optical and electro-optical properties of new generation LCDs displays addressing a particular attention to LCs blue phase hosting gold nanoparticles. Moreover, we focus on the progress of electrofluidic displays, which demonstrates characteristics that are similar to LCDs, with attention on various pixel designs, operation principles and possible future trends of the technology. 相似文献
7.
《Food Control》2015
In this work a multicommuted flow system employing copper–4,4′- dipyridyl coordination compound as the solid-phase reagent for the spectrophotometric determination of reducing sugar was developed. The coordination compound was synthesized through a reaction of the 4,4′-dipyridyl and copper (II) nitrate, under hydrothermal conditions. The complex was characterized by infrared spectroscopy (FTIR), power X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and thermogravimetric analysis (TGA). Based on the characterization, a multicommuted spectrophotometric procedure for the determination of reducing sugar using copper (II) complex as solid reagent is proposed. The proposed method was based on the redox reaction between a monosaccharide, such as fructose and glucose (reducing sugar) and Cu(II). This reaction, mediated in an alkaline medium, produces a yellow compound that can be determined by absorption electronic spectroscopy (λABS = 420 nm). Under optimum experimental conditions, a linear response ranging from 1.0 to 20.0 g L−1 (R = 0.9978 and n = 5), a detection (3σ criterion) and quantification (10σ criterion) limit estimated at 0.23 and 0.75 g L−1, respectively, a standard deviation relative of 4.7% (n = 7), for a reference solution of 10.0 g L−1 reducing sugar, and a sampling rate of 75 determinations per hour were achieved. The proposed system was applied to the determination of reducing sugars in coconut water and juices. The analysis of ten samples and the application of the t-test to the results found, and those obtained using reference procedures (AOAC), provided no significant differences at a 95% confidence level. This system enabled the analysis of reducing sugar with ease and simplicity, providing a significant economy of the solid reagent (600 μg per determination) and reducing effluent generation. 相似文献
8.
9.
Weigang Liang Beibei Wang Guofeng Shen Suzhen Cao Bertrand Mcswain Ning Qin Liyun Zhao Dongmei Yu Jicheng Gong Shanshan Zhao Yawei Zhang Xiaoli Duan 《Indoor air》2020,30(2):264-274
Stunting adversely affects physical and mental outcomes of children. It has not been examined whether household air pollution from solid fuel combustion is a risk factor for stunting in children. In a total of 41,439 children aged 6-17 across China, height was measured using a unified protocol. Multivariable linear regression models and logistic regression models were used to assess the associations of solid fuel use for cooking/heating with stunting in children. Adjusted for covariates, cooking/heating with solid fuel was significantly associated with a lower z-score for height for age and sex (β = −0.21 [−0.32 to −0.09] and −0.17 [−0.31 to −0.03], respectively) and an increased risk of stunting with an estimated ORs of 1.34 [1.07~1.68] and 1.37 [1.02~1.83], respectively. The risk of stunting associated with solid fuel use was statistically significant in high-age children. And the effect was greater on girls than on boys, though the difference was not statistically significant. Our study suggested that Chinese children living in households using solid fuel had a significantly higher risk of stunting than those living in households using cleaner fuel. 相似文献
10.
随着我国石油需求量不断增加,致密油藏的开发也愈发重要。如何高效开发致密油藏是一项重点难点,其中致密油藏注天然气提高采收率是一个极具潜力的研究方向。因此,本文着重介绍以天然气作为能量补充介质在国内外的研究现状和应用现状,并且从两相特征等方面总结了理论研究中的一些机理,对致密油藏注天然气提高采收率的发展前景进行了一定的展望。 相似文献