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Abstract As energy consumption in residential areas is rising, rooftop PV and small wind turbines have been widely deployed in residential areas to save energy cost. How to achieve efficient use of distributed energy has become the current focus. This paper proposes a home energy management system based on an Energy Router. The Energy Router with plug-and-play and load switching functionality can make maximum use of renewable energy. With the novel design of switch array within the energy router, operation of the home appliances can be scheduled to minimize the total cost of energy consumption. Based on the above system design, a hardware experiment platform was built. The experimental results show that the Energy Router enables seamless switching of the loads between different energy sources, according to their priorities and their requirements on power quality. The switching of the loads between different power sources make it possible to take full use of the renewable energy within the HEMS, and the process of switching is seamless so that the operation of the loads will not be affected. [ABSTRACT FROM AUTHOR]

Abstract A novel energy router with multiple operation modes is presented for energy prosumers with distributed energy sources and battery units. The energy router has two alternating current (AC) buses, one of them is connected to the renewable energy sources and battery unit, the other is connected to the grid. The novel feature of the energy router is facilitated by a "switch array" between the two AC buses. Besides the grid-connected and islanded modes, the energy prosumer can also operate under a "parallel mode", in which the loads are enabled to be connected to different AC buses and can even be switched between the two AC buses, through proper operation of the switch array. The MATLAB/Simulink model of an energy router with multiple operation modes for a residential energy prosumer is established, and a hierarchical control scheme is proposed for the energy router. A fuzzy logic strategy is designed to control the switch array. Simulation results show that the parallel mode has ensured: 1) The AC loads can be chosen to be connected to either of the two buses according to their power quality requirements; 2) Renewable energy can be consumed within the energy prosumer itself, so the negative effects of harmonic components caused by power electronics devices and fluctuation of renewable energy to the power grid can be reduced as much as possible. [ABSTRACT FROM AUTHOR]

Adsorptive removal of the predominant polycyclic aromatic hydrocarbons (PAHs), represented by phenanthrene, from hot gases using mesoporous adsorbents (mesosilicas MCM-41 and SBA-15, and mesocarbon CMK-3) has been studied through tests of column adsorption and temperature programmed desorption (TPD). Adsorption equilibria on MCM-41 and CMK-3, and on SBA-15 were well described by Langmuir and Freundlich models, respectively, showing the order of adsorption capacity of CMK-3 > SBA-15 > MCM-41 originated from different geometrical structures and texture properties. Adsorption dynamics based on breakthrough fitting by the constant-pattern wave propagation model showed that mesoporosity contributed to fast overall adsorption kinetics by reducing the internal resistance as being the predominant mass-transfer step, particularly on SBA-15 with a 2-D cross-linked structure. The TPD tests revealed the order of ease of desorption of SBA-15 ≈ MCM-41 > CMK-3, where the structural advantage on SBA-15 dominated the strong site binding as indicated by the intrinsic activation energy and exponential factor obtained by TPD models. Results from different TPD models showed that re-adsorption effect during desorption increased with decreasing dimension of adsorbent structure and that the utilization of the simplified linear TPD model could be violated by the strong sorbate-sorbent binding. Comparisons with traditional adsorbents and with the removal of naphthalene by these mesoporous adsorbents were made, showing higher applicability of CMK-3 for phenanthrene regarding stronger adsorption affinity and capacity as well as decreased disadvantages in regenerability relative to mesosilicas. [ABSTRACT FROM AUTHOR]

Adsorption is a promising technology for capturing nitrogen oxides (NO x) from humid flue gases, for which as the preferred NO x adsorbent, zeolite with an appropriate silica to alumina (Si/Al) ratio provides the key step for success in practical applications. In this work, the effects of Si/Al ratio, temperature, relative humidity (RH), and feed gas (NO x -H 2 O(g)–CO 2 –O 2 -N 2) compositions on NO x sorption behavior on HZSM-5 zeolites were systematically investigated, based on a series of characterizations, fixed-bed adsorption and temperature programmed desorption (TPD) tests. The low-silica HZSM-5(25) showed the best performance (326.6 μmol/g and 39.2 μmol/g at dry and 90%RH) as compared to others with higher Si/Al ratios at each RH, in which the roll-up effect was positively correlated with the Si/Al ratios and humidity. O 2 enhanced NO x adsorption and reached an optimal adsorption capacity at the concentration of 14%, while CO 2 had little effect on NO x adsorption. The decrease in temperature increased NO x adsorption capacity on HZSM-5(25), benefitting from NO 2 physisorption as well as satisfactory NO oxidation within the active adsorbent structure. The facile thermal desorption of NO x and significant NO–NO 2 conversion on HZSM-5(25) was exhibited by bimodal TPD peaks at 343–353K and 533–543K respective for NO and NO 2 , in contrast to those on Silicalite-1. A potential "water-resistant" strategy via the enhancement of NO x adsorption competitiveness was revealed, providing a theoretical guideline for NO x adsorbent screening in industrial applications. [Display omitted] • Influential rules of multiple factors on NO x adsorption are systematically explored. • Low-silica HZSM-5 shows the best NO x adsorption performance at each condition. • Contributions of NO oxidation and NO 2 physisorption at varying temperatures are shown. • Greater regenerability of NO x from NO x -H 2 O(g)–CO 2 –O 2 -N 2 feed on HZSM-5 is demonstrated. • A "water-resistant" strategy for enhancing NO x adsorption competitiveness is proposed. [ABSTRACT FROM AUTHOR]

Huge numbers of residential energy prosumers (EPs) will be widely deployed in the next generation power system which is dominated by renewable energies. The intermittent and non-dispatchable natures of the renewable energies will inevitably bring sporadic and unpredictable disturbances to the power system, making "grid friendliness" an essential requirement for the EPs. To tackle this problem, this paper focuses on the hardware implementation of the energy router (ER) and corresponsive coordinated energy management strategy for grid friendly EPs. The coordinated energy management strategy, combined with a fuzzy logic controller (FLC) for energy storage (ES) unit control and an improved discrete binary particle swarm optimization (DBPSO) algorithm for load scheduling, is elaborated for embedded control of the ER by maintaining balance of the accuracy, efficiency and cost considerations. Built as the energy interface between the EP and the power system, the ER is facilitated with plug-and-play source/load/ES connections, intelligent monitor and control interfaces as well as a load switching module, enabling the functionalities of the coordinated energy management strategy to be implemented. Experimental verification shows that, the developed ER enhances the energy management flexibilities for the EP, and the presented FLC + DBPSO algorithm enables coordinated operation of the EP and potential benefits in renewable DG utilization by improving the performances of PV self-use ratio, load rate and energy cost of the EP system by about 20 %, 50 % and 20 %, respectively, while at the same time maintaining the EP system reliability and consumer comfort, as well as meeting the grid friendly requirements. [ABSTRACT FROM AUTHOR]

• A visualization experimental system for NO 2 gas condensation is designed. • Fog, droplet-streamlet-film (DSF), and freezing condensation modes are revealed. • Formations of DSF mode divided into 4 periods at varying conditions are quantified. • Relationship between mode evolution and heat transfer performance is demonstrated. • Insight into evolution of each mode regarding NO 2 -N 2 O 4 dimerization effect is gained. Pure nitrogen dioxide (NO 2) is a profitable feedstock for production of various chemicals. The condensation technology plays an essential role in NO 2 enrichment during production or resource recovery from industrial exhausts, which, however, remains challenging in process optimization due to the lack of thorough comprehension on NO 2 condensation behavior. In this work, the visualization experiments of NO 2 condensation on the vertical SS316 surface at varying temperatures, NO 2 mole fractions and volume flow rates in the absence and presence of non-condensable gas (NCG) were conducted. Three major NO 2 condensation modes, the fog mode, the droplet-streamlet-film (DSF) coexistence mode, and the freezing mode, have been identified. The formation process of NO 2 gas-fog-droplet-DSF mode as well as the occurrence frequency of streamlets (OFS) was quantified under different conditions. The higher OFS was found to contribute to greater overall heat transfer coefficient and condensate amount, showing the optimal parameters at each condition. Deeper insights into gas-fog, gas-liquid, and gas-ice phase transformations for NO 2 were gained, revealing the unique effects of dimerization of NO 2 to N 2 O 4 on condensation. The dimerization triggers the facile formation (< 10 s) of N 2 O 4 fog with increased intermolecular forces, the heterogeneity of heat and mass transfer in DSF mode with complex heat resistance network and condensate states, and the melting-thickening cycle of ice layer in the freezing process along with the release of dimerization reaction heat. The findings render a microscopic view of favorable heat and mass transfer towards optimal NO 2 condensation strategies in practical uses. [Display omitted]. [ABSTRACT FROM AUTHOR]

Abstract: In order to solve hypoxic problems in high altitude area and ensure workers life safety, a new cycle named as Low Pressure Swing Adsorption for oxygen concentration was proposed. In this cycle, the high efficiency liking Vacuum Pressure Swing Adsorption was obtained but the vacuum was not used. The relationship between oxygen concentration and oxygen flux was revealed. And the matching air content curve in different altitudes was acquired. Basing on the experiment data, the life safety system with oxygen supplied for workers was suggested. After using this system, the oxygen partial pressure of the tunnel face could be enhanced by 2 – 3kPa and the incidence of AMS in the workers decreased significantly, blood oxygen saturation increased, pulse rate and breaths per minute decreased. [Copyright &y& Elsevier]

Abstract: Carbon dioxide is one of greenhouse gases. The development and application of carbon dioxide capture storage technology can not only alleviate the current pressure on the environment of global warming, but also can bring huge economic benefits. At present, the commonly methods of carbon dioxide separation are chemical absorption, physical absorption, membrane separation and adsorption separation. These Separation methods all have own characteristics in economy, selectivity and applicability. But Chemical Absorption Method and PSA are used more widely in industry. So several capture methods by chemical absorption or PSA were suggested for carbon dioxide emission form flue gas in coal-fired power plant, exhaust gas of industrial furnace or biogas. [Copyright &y& Elsevier]

Capturing and recovering naphthalene as a profitable chemical from hot flue gas are of significance in terms of environmental protection with economic benefits, for which the adsorption technology using high-performance sorbents provides the key step for success in practical applications. Carbonaceous materials with hydrophobic natures have been shown to render high affinities with non-polar naphthalene, but remain challenging due to difficulties in tackling the trade-off between adsorption and desorption. This work reports a systematic investigation with deeper insights into adsorption equilibria, kinetics and regenerabilities of gaseous naphthalene on typical carbonaceous sorbents originated from different texture properties, including ordered mesoporous carbons (CMK-3, CMK-5 and FDU-15), carbon nanotubes (SWCNT and MWCNT) and a coconut-shell-based activated carbon (AC). The adsorption isotherm and breakthrough curves at wide feed concentration ranges and temperature programmed desorption curves for each sorbent were obtained along with series of theoretical model fitting. FDU-15 and CMK-5 were demonstrated as superior sorbents with high maximum adsorption capacities (1.13 and 1.735 mmol/g) and low desorption activation energy (62.66 and 72.68 kJ/mol), respectively exhibiting advantages of the 3-dimensional diffusion-controlled desorption upon a hexagonal pore arrangement and the efficient adsorption upon a reasonable mesopore-micropore hierarchical structure, in contrast to poor kinetics on pure microporosity (AC) and 1-dimensional topologies (CNTs). Deeper insights into the morphology-affinity relationship revealed advantageous naphthalene transport behaviors over 3-dimensional ordered mesoporosities with appropriate coexisting microporosities and narrower primary size (2–5 nm) or diverse forms of mesopore, which contribute toward reaching comprehensive balances of sorption performances. [Display omitted] • Adsorption equilibria of gaseous naphthalene on carbonaceous sorbents are obtained. • Regenerability with desorption kinetic triplet for each sorbent is quantified. • Ordered mesoporous carbons, FDU-15 and CMK-5, are demonstrated as superior sorbents. • 3-dimensional ordered mesoporosities with narrower primary size (2–5 nm) are favored. • Micropore-mesopore hierarchical structure gives high adsorption/desorption kinetics. [ABSTRACT FROM AUTHOR]

Li-LSX (low silica type-X) zeolite is the sorbent of choice for air separation by adsorption today. Li-LSX is obtained by ion exchange of Na-LSX. The occupancy of Site III (SIII, which is the open site in the supercage) by Li + is crucially important for N 2 adsorption. In this work, mixed-cation LiNa-LSX zeolites were prepared and N 2 adsorption isotherms were measured. The isosteric heats of adsorption of N 2 were obtained from the temperature dependence. The heats of adsorption remained at approximately 17.7 kJ/mol (i.e., that for pure Na-LSX) at Li + exchange below approximately 70%, and increased upon further increase in Li + exchange, to 22.6 kJ/mol (i.e., that for pure Li-LSX). The increase was not linear (i.e., concave shaped), however, which indicated that one N 2 molecule could likely adsorb on two adjacent cation sites. The relationship between heat of adsorption and Li ion occupancy on site SIII was obtained. It is suggested that this relationship may be used to estimate the occupancy by Li + on SIII of faujasite type of zeolites. [ABSTRACT FROM AUTHOR]

High-volume production of oxygen and nitrogen from atmospheric air is accomplished by cryogenic distillation. Prior to feeding to the air separation unit, the ambient air must be pre-purified by the removal of trace impurities such as CO 2, H 2 O vapor, and light hydrocarbons (e.g., CH 4 ) to their tolerable limits of 1.0 ppm, 0.1 ppm, and to a few ppb, respectively. In this study, the adsorption characteristics of a synthetic zeolite, Li-LSX (where LSX denotes low-silica type-X zeolite where Si/Al=1), for the removal of trace amounts of CO 2 , CH 4 , and H 2 O vapor impurities were analyzed and compared with the conventional synthetic 13X zeolite that has been used for air prepurification as well as the ion-exchanged K-LSX and Ca-LSX zeolites. Isotherms to very low partial pressures (to a few ppm of 1 atm) were measured. The Tὸth, Langmuir–Freundlich (L–F), and the Dubinin–Astakhov (D–A) isotherm models were used to correlate the low pressure experimental data and the Tὸth model was found to be the better fit especially in the low pressure range. The superior adsorption properties of Li-LSX for air prepurification are demonstrated in this work. [ABSTRACT FROM AUTHOR]

Highlights • LSX containing minimum Li and Ag were prepared and evaluated for air separation. • ion exchange procedures were designed to miniemize Li+ on inaccessible sites. • The mixed-cation LSX were compared against pure Li-LSX for air separation by PSA. • The mixed cation zeolites show promising performance for replacing Li-LSX. Abstract Mixed-cation LiSr-LSX, AgCa-LSX and AgSr-LSX containing minimum lithium and silver were prepared by exchanging small fractions of Li+ into Sr-LSX and Ag+ into Sr-LSX and Ca-LSX. To avoid diffusion of the Li+ into the inaccessible sites, the LiSr-LSX sample was exposed to a specifically derived dehydration condition. Similarly, the mixed-silver cation samples were treated to the selected condition post-ion-exchange to allow the Ag+ to migrate into SII*. Strong evidences were provided that significant fractions of the exchanged Li+ and Ag+ remained in SIII and SII* respectively after comparisons of the N 2 /O 2 adsorption isotherms and isosteric heats of adsorption of the mixed-cation and single-cation samples. Furthermore, the mixed-cation LiSr-LSX, AgCa-LSX and AgSr-LSX samples were compared against the single-cation Li-LSX sample based on their O 2 productivity performance via a PSA simulation model. [ABSTRACT FROM AUTHOR]

Abstract The removal characteristics of sub-25 nm ultrafine particles (UFPs) by different porous nanomaterials with different morphologies were studied based on efficiency curves obtained with specially designed filtration system. The material morphological effects on UFPs collection were investigated. The results demonstrate a complex and synergic mechanism of material structural framework, pore size distribution, and porosity order in terms of diffusion and interception dependent on flow velocity. Both porosity and fiber-like tubular structures promoted the UFPs removal. Microporosity and disordered mesoporosity could enhance the roughness of the internal surface and intensify the interaction with UFPs. Specifically, the large and ordered mesoporosity was able to render selectivity for UFPs at certain sizes and exhibited the best particle collection performance which can be largely associated with significant pore size and volume. The dependence of the ratio of diffusion to interception on flow velocity and the comparison of different pores in terms of the matching sizes with particles derived from single sphere efficiency model fitting results were also discussed. This work is significant to deeper understanding of interactions between airborne nanoparticles and porous surfaces. Graphical abstract Unlabelled Image Highlights • UFPs removal by porous materials with different morphologies was explored. • Effects of structure, pore size and order on particle collection was studied. • Relationship between diffusional collection and mesoporsity was addressed in theory. [ABSTRACT FROM AUTHOR]

Airborne ultrafine nanoparticle (UFNP) is a key factor causing heavy haze pollution in Beijing-Tianjin-Hebei, which is very harmful to human health and the environment. Removal of environmental UFNPs by porous material is an important method of air purification treatment. However, the specific mechanism by which porous material filters UFNPs is not clear. In this study, UFNPs with 2–10 nm diameter were removed by SBA-15 mesoporous silica molecular sieves with different pore sizes, and the filtration mechanism was analyzed using transmission electron microscopy (TEM), specific surface area tests (BET), and X-ray photoelectron spectroscopy (XPS). The analyses showed a distinctive filtration of UFNPs over the interior mesopore channels. The removal efficiencies of SBA-15 with different pore sizes were also compared, demonstrating the influence of the pore size and structure on most penetrating particle size (MPPS). The UFNP filtration efficiency of SBA-15 increased with the increase of pore size. Moreover, SBA-15-14.6 could effectively purify UFNPs, and it had the highest fractional diffusive filtration efficiency of 98.79% and a total efficiency of 92.58% for UFNPs. This study provides a technical basis for the filtration of UFNPs using mesoporous materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Separation mechanisms for CO2/CO mixture were studied systematically by experiments and simulations. • The NaX zeolites showed low adsorption heat and high separation coefficients on CO2/CO. • The CaA zeolites showed excellent separation stability under different ratios for CO2/CO mixture. • The above separation performances were revealed by the number, distribution and charge of cations and characteristics of gas adsorption complexes. Adsorption and recovery of CO 2 from industrial gases are of great environmental significance in the field of environmental protection with reducing greenhouse gas emissions and increasing CO concentration. A comprehensive investigation with thermodynamics and kinetics experiments of CO 2 and CO on NaX and CaA zeolites were studied and the separation mechanism explained by molecular simulation methods. The experiments show that the NaX zeolites have significant differences on CO 2 and CO adsorption amounts leading the high CO 2 /CO selectivity, while the CaA zeolites exhibit separation stability under various partial pressures of mixed gas, which is supported by the standard deviation results. The theoretical simulations verify the above-mentioned experimental phenomena and provide a visual mechanism explanation for adsorption selectivity from the aspect of systematic interaction between cations and gas molecules. Compared with NaX, the same number and homogeneous distributions of Ca2+ and Na+ in the CaA provide stable separation performance. The strong electrostatic interactions between divalent Ca2+ and gas molecules especially CO make differences in the order of adsorption capacity and adsorption heat. Deeper insights into the cations-gas adsorption complexes revealed that the significant differences in the types of adsorption complexes for CO and CO 2 in NaX contribute to the improvement of the adsorption selectivity. [ABSTRACT FROM AUTHOR]

Three acute hepatic injury models (a CCl 4 -induced model, APAP-induced model and ethanol-induced model) in mice were used to study the importance of GSTA1 in acute hepatic injury by comparison with a standard enzyme marker, alanine aminotransferase (ALT). GSTA1 release was demonstrated to be an earlier and more sensitive indicator of hepatotoxicity than was ALT. Significant increases in GSTA1 were detected at 2 h after CCl 4 exposure, while ALT was undetected at this time. GSTA1 was also a more sensitive indicator of hepatotoxicity than ALT after 6 h. In the APAP and ethanol models, GSTA1 was markedly increased earlier than ALT, at 2 h post exposure. The release of GSTA1 was significantly increased at a dose of 12.5 mg/kg (CCl 4 model), 100 mg/kg (APAP model) and 10 ml/kg (ethanol model), the lowest exposure concentration for each model. In contrast, AST release was not statistically significant. These results suggest that GSTA1 can be detected at low concentrations during the early stages of acute hepatic injury and that GSTA1 is a more sensitive and more accurate indicator than ALT. [ABSTRACT FROM AUTHOR]