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[en] The fascinating capability of manipulating light using metamaterials (MMs) has inspired a significant amount of studies of using MMs for energy related applications. In this work we investigate MM-based perfect absorbers for enhancing near field radiative heat transfer, which is described by the fluctuation dissipation theorem. MM structures designed at two wavelengths are analyzed, corresponding to two working temperatures. Both electric and magnetic surface polaritons are found to contribute to heat transfer, while natural materials support only electric polaritons. The near-perfect absorption is demonstrated to be related to the modification of effective optical properties, which is important for enhancing radiative heat transfer efficiently. By comparing different designs, the bandwidth of the heat flux spectrum is found to increase with the absorption bandwidth, which is originated from the spatial field distributions. This study will contribute to the understanding of surface polaritons in near field radiative heat transfer and facilitate the optimization of MMs for near field heat transfer applications.
[en] Using Monte-Carlo method, the electron transport and energy deposition in material are calculated. Combining with the elastic-plastic hydrodynamic equations, numerical results cover the thermal-mechanical effect and the blow-off impulse on Ly-12 Al induced by irradiating of the impulsive electro-beam which caused by 'FLASH II-an impulsator of relativistic electron beams. These results are compared with the experimental data
[en] Aims: This paper aims to evaluate local enforcement of China's mandatory appliance and equipment energy efficiency standards and labeling programs, two increasingly important policies for meeting national energy and carbon reduction targets. The expected energy savings of efficiency standards and labels can be fully realized only with strong enforcement to ensure compliance for all products sold. This paper provides comprehensive retrospective evaluation of the methodologies, results, progress and remaining challenges in pilot enforcement projects initiated in the absence of consistent national check-testing focused on energy efficiency. Scope: This paper's scope is focused on 2006–2009 pilot local check-tests conducted to verify appliance and equipment compliance with China's mandatory energy label and efficiency standards. Conclusions: This paper finds both improvement and some backsliding in compliance rates over time. Compared to earlier efforts, 2009 check-tests covered a wider regional and product scope but demonstrated greater variation in compliance rates. Labeling display and energy efficiency compliance was generally high across regions and most products, but lower compliance rates were observed in less economically developed regions and for lighting and industrial products. Based on these findings, areas for improvement in local awareness, product sampling methodology, check-testing tools and procedures are identified. - Highlights: • China's mandatory standards and labeling crucial to national energy saving goals. • China's 2006–2009 pilot efficiency check-testing for standards and labeling evaluated. • Wider geographic and product scope in 2009, but greater variation in compliance. • Generally high compliance, but lower rates for less economically developed region. • Local check-test capacity improving but methodological challenges remain
[en] This paper restudies the method of direct chelatometric titration of V(IV) with N-benzoyl-N-phenylhydroxylamine (BPHA) as indicator. The indicator functions entirely differently from indicators hitherto used in chelatometry. The solution contains two independent systems - the indicator and the titrand-titrant system - without any color changing species. The BPHA-V(V) chelate once formed as the result of aerial oxidation constitutes the indicator system and does not react with EDTA. Its color therefore remains unchanged throughout titration. It is not a metallochromic indicator. Its function is that of color-screening. The color of the titrant system deepens during titration, but does not change. The end-point is indicated by one color completely covering up the other. Hence, this method is of purely empirical nature. Refs. 12 (author)
[en] The thermal-mechanical effects generated by the pulse ion beam with different energy are numerically studied using ITSW code. The characteristics of the effects, such as energy deposition, ablation, blow-off impulse and thermal shock wave, are obtained
[en] Chronic hypertension induces vascular remodeling. The most important factor for hypertension treatment is reducing the risk of cardiovascular disease. OW1 is a novel imperatorin derivative that exhibits vasodilative activity and antihypertensive effects in two-kidney one-clip (2K1C) renovascular hypertensive rats. It also inhibited vascular remodeling of the thoracic aorta in a previous study. Here, the inhibitory effects and mechanisms of OW1 on arterial vascular remodeling were investigated in vitro and in 2K1C hypertensive rats in vivo. OW1 (20 μM, 10 μM, 5 μM) inhibited Ang II-induced vascular smooth muscle cells (VSMCs) proliferation and ROS generation in vitro. OW1 also reversed the Ang II-mediated inhibition of α-SMA levels and stimulation of OPN levels. Histology results showed that treatment of 2K1C hypertensive rats with OW1 (20, 40, and 80 mg/kg per day, respectively for 5 weeks) in vivo significantly decreased the number of VSMCs, the aortic cross-sectional area (CSA), the media to lumen (M/L) ratio, and the content of collagen I and III in the mesenteric artery. Western blot results also revealed that OW1 stimulated the expression of α-SMA and inhibited the expression of collagen I and III on the thoracic aorta of 2K1C hypertensive rats. In mechanistic studies, OW1 acted as an ACE inhibitor and affected calcium channels. The suppression of MMP expression and the MAPK pathway may account for the effects of OW1 on vascular remodeling. OW1 attenuated vascular remodeling in vitro and in vivo. It could be a novel candidate for hypertension intervention. - Highlights: • OW1, an imperatorin derivative, attenuates vascular remodeling caused by hypertension. • OW1 inhibits VSMC proliferation and media layer hypertrophy. • OW1 acts as an ACE inhibitor and affects calcium channels. • Suppression of MMPs expression and MAPK pathway may account for the effects of OW1 on vascular remodeling
[en] A gas atomization process has been explored to enhance the microstructure and grain refining performance of Al-5Ti-1B master alloy. The results indicate that a gas atomization process has evidently alleviated the aggregation tendency of TiB particles and refined TiAl particles, resulting in a fine uniform dispersion of TiB and TiAl particles. Grain refining performance tests showed that the gas atomized Al-5Ti-1B master alloy effectively refined the average grain size of commercial purity Al from 2500 μm to 183 μm after 2 min of its inoculation, and the average grain size remained at 229 μm after inoculation for 180 min. The gas atomized Al-5Ti-1B master alloy demonstrated a much better grain refining efficiency and higher anti-fading ability than that of the as-cast Al-5Ti-1B master alloy.
[en] We investigate the dynamics of entanglement between two remote, macroscopic, mechanical modes in a model consisting of two cavities, with each cavity containing a two-level atom and having one movable mirror. The results show that the time evolution of entanglement exhibits periodic behavior that does not depend on the atomic coherent angles and that the amount of entanglement increases with increasing atomic coherent angle. A maximally entangled state between mechanical modes can be prepared. We find a simple method for inferring the entanglement properties between two mechanical modes. We propose a potential way to control and manipulate the entanglement.
[en] By carefully controlling the experimental parameters, large-scale nanosponges of group II-B metal (Zn and Cd) on Si substrates are fabricated through a vacuum vapor deposition route (VVD). The as-prepared products are systematically characterized by the techniques of powder x-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It is shown that nanosponges are composed of network nanowires, which are 20-250 nm in diameter and hundreds of micrometers in length. On the basis of the time-dependent experimental findings, the nucleation and growth of the nanowires have been elucidated. Moreover, the melting behavior of a single ultrathin zinc nanowire was observed in situ under the irradiation of an electron beam during the TEM measurement for the first time, showing that the melting point of the ultrathin zinc nanowire is significantly lower than that of the bulk.
[en] This study uses bottom-up modeling framework in order to quantify potential energy savings and emission reduction impacts from the implementation of energy efficiency programs in the building sector in China. Policies considered include (1) accelerated building codes in residential and commercial buildings, (2) increased penetration of district heat metering and controls, (3) district heating efficiency improvement, (4) building energy efficiency labeling programs and (5) retrofits of existing commercial buildings. Among these programs, we found that the implementation of building codes provide by far the largest savings opportunity, leading to an overall 17% reduction in overall space heating and cooling demand relative to the baseline. Second are energy efficiency labels with 6%, followed by reductions of losses associated with district heating representing 4% reduction and finally, retrofits representing only about a 1% savings. - Highlights: • We use a bottom-up modeling approach to quantify emission reduction from efficiency programs. • Heating and cooling are the main focus of this study. • We find that building codes lead to 17% reduction compare to the baseline. • Other programs analyzed concern district heat, building labeling and retrofits of buildings.