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In this paper, in order to reduce the preparation cost of high-performance ceramic membrane, coal fly ash-based tubular ceramic membrane for flue gas moisture recovery was prepared, and its properties were optimized from two aspects: pore-forming agent (dextrin) content and sintering temperature. The results show that the ceramic membrane with dextrin content of 3 wt.% and sintering temperature of 1150 ℃ has the best performance. Through characterization, the ceramic membrane exhibits an open porosity of 42.0 %, mechanical strength of 26.6 MPa, average pore size of 0.49 μm, pure water flux of 5616 L/(m2 barh). And, it has excellent corrosion resistance in acid and alkali. In addition, the flue gas moisture recovery performance of coal fly ash-based tubular ceramic membrane was studied experimentally. The highest water recovery ratio and the highest recovered water flux is 87.7 % and 6.01 kg/(m2 h, respectively.

Concentrated photovoltaic (CPV) is raised because of the high cost of solar cells. However, the commercial solar cell is designed with 1 sun. The electrical power will not have the consistent ratio with the increase of concentration ratio. This paper proposes the slicing solar cell to connect commercial cell and CPV. And the experimental research of slicing cells with variable-controlling approach is carried out with different concentration ratio. The results show that slicing design can reduce the output current and power loss caused by series resistance, and remove the upper limit of output current caused by thin grid line. The slicing cell is more suitable for concentrated light condition than normal cell. The power difference between the slicing cell and the normal cell can reach 40 W with 4 suns. Slicing crystalline silicon solar cells have great potential in concentrated photovoltaics.

This paper presents a low concentrating photovoltaic/thermal (LCPV/T) collector with thermoelectric generator (TEG) which is connected in series. LCPV/T produces heat and electricity while TEG transforms low-grade heat which is gained from LCPV/T into high-grade electricity. In this paper, the mathematical model is built, and the test rig is established to validity the numerical model. The performance of the proposed system under different ambient conditions is studied by test rig with biaxial tracking system. Besides, the effects of environmental parameters, the economic analysis and energy saving of the system in different seasons are also analyzed. The study result shows that the PV/T collector produces the maximum temperature of domestic hot water about 52.96 °C and a daily average electric power of 436.13W with daily average electrical efficiency of 14.34% in summer. By using the TEG module, another 1.68W (2.85‰ of the 436.13W) is generated in summer. In addition, the performance between LCPV/T in series and in parallel is researched. Moreover, the system have the potential of reducing the use of primary energy.

The combination of photovoltaic and photothermal, often abbreviated as PV/T, is a promising approach that has been increasingly studied to improve solar energy conversion efficiencies. In this paper, a low-concentration bifacial PV/T system (LC-BiPV/T) which uses double-axis tracking module and direct-contact glass-channel was built. The electric and thermal performances of this system are studied experimentally. When the series and parallel waterflow configuration is compared, the result shows that the average electric efficiency of the direct contact glass-channel LC-BiPV/T system is 13% and the average thermal efficiency is 48.13% when running at series configuration. When the average electric efficiency is 14.90% and the average thermal efficiency is 58.69% at parallel configuration. In general, the thermal and electric performance of this system are excellent, and the series configuration can further improve both efficiencies of the system. This experimental result can aid on the improvement of future energy-using.

Inorganic ceramic membrane has the advantages of excellent thermal stability, mechanical strength, chemical resistance and fouling resistance. And it has been widely studied and applied in flue gas moisture recovery, gas purification and wastewater treatment. The support is the basis of preparation and application of inorganic ceramic membrane, and its performance determines the performance of the ceramic membrane to a certain extent. At present, extrusion is a common method used in the ceramic industry to prepare supports, which has the advantages of high production efficiency and good product uniformity. In this paper, the processes of preparing support by extrusion including mixing, vacuum pugging, aging, extruding and sintering are introduced in detail. In preparing support by extrusion, the product performance is easily affected by many factors, including the type of raw materials, raw material particles, extrusion parameters, pore-forming agents, sintering temperature, and sintering aids. Therefore, this paper also conducts a comparative and comprehensive study on the process parameters and influencing factors in the process of preparing ceramic membrane support by extrusion to obtain the support with the best performance. The main influencing factors that this paper focuses on are the types of raw materials, powder particles, water content, pore-forming agents, binders, sintering temperature, and sintering aids. The trends and mechanisms of these factors affecting the performance of the support are analyzed in detail.

In the present study, a novel low-concentrating photovoltaic/thermal solar assisted water source heat pump (LCPV/T-WWHP) system is developed to satisfy both electricity and thermal demand of a university building. This system comprises of low-concentrating photovoltaic/thermal (LCPV/T) modules, a water-to-water heat pump (WWHP), storage tanks, and capillary network. The performance of this system is theoretically investigated by the mathematical model of exergy. Conclusion can be drawn from the experiment that the tracking radiation and the inlet temperature of the evaporator play a crucial role of the system. The maximum electrical efficiency is 15.2%, with an average of 9.4%. In addition, the maximum thermal efficiency is 86.7%, with an average of 54.8%. The WWHP operates stably, with the coefficient of performance greater than 4. The exergy efficiency of LCPV/T and the WWHP system are 11.8% and 73%, respectively. Consequently, the combination of LCPV/T and WWHP system can not only improve the performance of each subsystem, but also provides a new proposal to popularize such a system in remote regions or reconstruction project in rural districts.

The nanofiber electrodes have been considered as promising candidates for commercial proton exchange membrane fuel cells due to their high catalyst utilization and enhanced mass transport efficiency. However, for the first time our research determined that the nanofiber electrodes were restricted by the poor chemical stability of the polymer carriers. To gain further insight into the durability of nanofiber electrodes, both cyclic voltammetry aging tests and Fenton's tests were conducted. Similar to previous reports, our research demonstrated that nanofiber electrodes showed remarkable stability in the cyclic voltammetry aging process. However, Fenton's tests indicated that nanofibers in the electrodes would decompose easily while being attacked by reactive oxygen species such as HO• or HOO•, which greatly limits their practicability and reliability. The different performances under the two tests also demonstrated that the cyclic voltammetry aging protocols, which have been applied extensively, cannot well mirror the real operating conditions of fuel cells.

As a form of solar energy utilization, photovoltaic/thermal (PV/T) modules generate heat and electricity at the same time. Relative to individual photovoltaic or photothermal, it has a higher efficiency. In this paper, a simulation process coupling optical, electrical and thermal models for a water based low-concentration photovoltaic/thermal module is established. The optical characteristics of the module are simulated by Monte Carlo method. The electrical and thermal characteristics are numerically simulated using the finite volume method. The simulated values of outlet water temperature, output current and output power are fit well with experimental values, which verifies the reliability of the simulation process. The effects of water inlet velocity, solar irradiation, water inlet temperature, ambient temperature and wind speed on the energy and exergy performances of the module are analyzed. Results show that the direct contact of the HTF with the backside of the solar panel and the use of bifacial solar cells give the module good electrical efficiency and an overall efficiency of over 65% in all simulations. By connecting modules in series, and the application scenario can be extended.

Many studies on the moisture recovery of flue gas by the membrane method use a single ceramic membrane tube to recover the simulated flue gas. In this paper, a membrane module array containing 46 ceramic membrane tubes was constructed to recover moisture and heat in real flue gas produced by a gas-fired boiler. The maximum recovered water flux was 15.77 kg/(m2·h), and the maximum heat flux was 14.83 MJ/(m2·h). Based on the experimental results, applying membrane module array in the thermal power plants could recover a considerable amount of water and heat. Recovering moisture could solve the water shortage problem of some thermal power plants, and decrease overall humidity in the lower atmosphere, which is conducive to the spread of pollutants in the lower atmosphere. Furthermore, the optimal boundary conditions of the experiments are discussed for guiding the actual production in the future. According to the results, the optimal operation temperatures of flue gas and cooling water are about 50 °C and 25 °C, respectively.

Micro-porous ceramic membrane tube is a new type of condensation material which can synchronously recover both water vapor and its accompanied latent heat from exhausted flue gas. The recovery outcome is helpful to reduce amount of make-up water and enhance boiler efficiency of thermal power plant. In this study, an experiment has been carried out to investigate condensation heat-transfer, water-recovery, and flow-resistance performance of micro-porous ceramic membrane tube bundle (CMTB), respectively. In addition, real exhausted flue gas with inlet flow rate ranging from 390 to 750 m3/h, temperature ranging from 323 K to 373 K was used as experimental feed gas. Results showed that the condensation heat-transfer process got more apparently with increasing of flue gas inlet temperature (from 335.3 K to 364.8 K). In addition, both cooling water flow rate and heat-transfer temperature difference had a remarkable influence on the water-recovery performance of the CMTB, and maximal water-recovery mass flow rate could reach 0.0336 × 103 kg/h. Most of all, velocity drop of flue gas was controlled within an appropriate range (from 28.94 m3/h to 178.78 m3/h). The application analysis on the CMTB gives a good perspective for designing high efficiency membrane-type condenser to recover water vapor from exhausted flue gas and make good use of its latent heat in the thermodynamic system of power plant.

Photovoltaic/thermal (PV/T) technologies are used to comprehensively utilize photovoltaic and solar thermal, among which concentrating PV/T technology can enhance the performance of a PV/T system. To analyze the performance of a LCPV/T system with a geometric concentration ratio of 4, the LCPV/T system and a conventional flat-plate PV/T system were fabricated and experimentally studied under a constant flow rate condition. The results show that the electrical power and thermal power of the LCPV/T system were 3 and 1.9–2 times more than those of the flat-plate system. The comparative experimental study indicates that the electrical performance of LCPV/T system is significantly greater than the flat-plate system, and the thermal performance of LCPV/T system slightly improved and should be optimized because of the heat transfer factor.

In this work, the controllable Ag/TiO2 SERS composites were successfully synthesized based on Ti foils with hydro-thermal treatment method. Flexible Ag/TiO2 SERS substrates could be pasted onto the surface of object with arbitrary shape to detect organic pollutants. Using R6G as probe molecule, Ag/TiO2 nonabelts could detect SERS signal up to 10−7 M. TiO2 can be used not only as the template of SERS substrate, but also as photo-catalytic material, which played a decisive role in photo-catalytic activity. The result of cycling experiment for the as-prepared SERS substrates indicated that it maintained good detection performance after 10 cycles.

Heat and water trans-membrane condenser (HWTMC) consisted of ceramic membrane tube bundles and cooling pathway is a functional apparatus to recover heat and water from flue gas in thermal power plants. In this study, the water and heat-recovery performance of 2 μm HWTMC on a gas-fired power plant was studied theoretically and experimentally. The simultaneous drop-wise/film-wise condensation heat transfer process was proposed in this study, and we investigated them by installing several temperature sensors within the HWTMC. In addition, the heat and water-recovery performance of HWTMC was evaluated respectively under different operational conditions, and the velocity loss of flue gas was also measured to verify its practicability. The experimental results showed that flue gas temperatures change significantly in the first 2/3 of the HWTMC unit, while barely change at end, especially when they are higher than 103.5°C. Compared with other operational conditions, moreover, a moderate cooling water inlet flow rate (0.3 m3/h) would result in a remarkable heat and water-recovery performance. To guarantee the efficiency of the experimental HWTMC with total membrane area of 0.145 m2, flue gas flow rate should be set under 500 m3/h. This paper is useful for membrane type waste heat and water-recovery installation design.

We carry out a systematic study of polarized- and temperature-dependent Raman scattering of layered Weyl semimetal NbIrTe4 on the (002) crystal surface, under parallel and perpendicular polarization Raman spectroscopy geometry in back scattering way, the angle-dependent Raman peaks intensity is recorded by rotating the single crystal from 0° to 360°, in combination with group theory analysis, all the prominent Raman peaks are assigned to A1 and B1 vibrational modes, moreover, we show that the angular dependence of Raman peak intensity of A1 mode is rather unusual and can be explained by complex values for Raman tensor elements, which is traced back to electron-phonon interaction in this material. Meanwhile, lattice anharmonic vibrational behavior is studied by investigating the temperature-dependent Raman scattering spectra, it is observed that all the Raman peaks show linear stiffening behavior as the temperature decreased from 293 K to 83 K, the temperature coefficients of four prominent Raman peaks suggest the anharmonicity of the lattice in layered NbIrTe4 crystal.

As a form of solar energy utilization, photovoltaic/thermal (PV/T) modules generate heat and electricity at the same time. Relative to individual photovoltaic or photothermal, it has a higher efficiency. In this paper, a simulation process coupling optical, electrical and thermal models for a novel double-axis tracking low-concentrating photovoltaic/thermal module is established. The optical characteristics of the module are simulated by Monte Carlo method. The electrical and thermal characteristics are numerically simulated using the finite volume method. The simulated values of outlet water temperature, output current and output power are fit well with experimental values, which verifies the reliability of the simulation process. Besides, the effects of gravity vector direction, water inlet velocity, solar irradiation, water inlet temperature, ambient temperature and wind speed on the energy and exergy performances of the module are studied. Relevant results can provide an effective basis for the proposal of module’s operation strategies.

Herein, a ternary Nb–Cr–C film is successfully prepared by arc ion plating for surface modification of titanium using as proton exchange membrane fuel cell (PEMFC) bipolar plates. Film morphology, composition as well as corrosion behavior, conductivity and performance of single cell are investigated. As results revealed, the Nb–Cr–C film is about 500 nm thick without obvious defects. Compared with the bare titanium, the corrosion current density of Nb–Cr–C coated titanium lowered to 0.022 μA/cm2 and -0.051 μA/cm2 in simulated PEMFC cathode and anode environments, respectively, accompanied with the interfacial contact resistance lowered to 1.15 mΩ cm2, indicating outstanding anti-corrosion and conductivity performance. The single cell with Nb–Cr–C coated titanium bipolar plates reaches its peak power density 1.167 W/cm2 at 2.2 A/cm2, which is comparable with that of graphite bipolar plates and apparently better than that of bare titanium bipolar plates. The remarkable improvements in both ex-situ tests and single cell tests suggest that the Nb–Cr–C coated titanium might be a proper material for PEMFC bipolar plates.

Water recovery from flue gas with transport membrane condenser (TMC) has gained much attention in recent years. It has great potential in water conservation and air pollution control. However, effects of porosity and pore size variation of macroporous membranes on TMC application have not been revealed. Coal fly ash (CFA) is used as main raw material to prepare various tubular macroporous ceramic membranes for TMC application. The extrusion method is adopted. Characterization of membranes are conducted for structural parameters evaluation. Prepared membranes were used for TMC application to experimentally study the water and heat recovery performance. Influences of temperatures and flowrates of flue gas and cooling water on recovery performance have been investigated. Increasing cooling water flowrate and flue gas temperature, as well as decreasing cooling water temperature can promote water and heat recovery performance of TMC. The highest water recovery efficiency is 79.21%. Although membrane pore size increasing improves water and recovery, the average pore size should be less than 2 μm to avoid transmembrane gas permeation. Results indicate that CFA membrane is suitable for TMC application and provides investment reduction.

Background: Uto now, COVID-19 has infected more than 60 thousand of people in China and is gradually spread globally The disease was named as Novel coronavir

We present a generalized three-mode cavity optomechanical system, where two cavity modes with strong control fields and weak signal fields are coupled to a common mechanical resonator. We find that the weak input signal fields will be entirely absorbed by the system without generating any energy output from each of the cavity modes termed coherent perfect absorption (CPA), and the two cavity modes and mechanical mode will share the input probe fields energy when CPA occurs under parameter regimes. With changing the parameter conditions, a weak input signal field will transmit from one cavity to the other cavity without undergoing any energy loss termed coherent perfect transmission (CPT). Moreover, the above phenomena are dependent on the coupling strength between the two cavity modes in this optomechanical systems. The origin and conditions that enable these phenomena to achieve are analyzed, and potential applications in quantum information may be realized in all-optical domain based on such phenomena.

This paper has made an active attempt on recovering water from flue gas using membranes. The properties of SPEEK/PES, a hydrophilic composite hollow fiber membrane, are studied in the present paper using experimental analyses of thermal gravimetric, differential scanning calorimetry and scanning electron micrograph. Experimental results show that SPEEK/PES composite hollow fiber membranes have excellent thermal stability and mechanical properties in flue gas. An experiment with using simulated flue gas (N2/water vapor mixed) is carried out to study the impact of sweep gas flow rate and feed gas temperature on the membrane module properties. The results indicate that the water recovery rate increases with the temperature increasing from 40 °C to 70 °C. The application of capturing the water in flue gas is very attractive, and it will provide a new way of saving energy and alleviating the haze.

A new method of water recovery from flue gas with hollow micro–nano porous ceramic composite membranes has been put forward in order to deal with the evaporated wastewater from thermal power plants. The feasibility of this method has been investigated in theory, and ceramic membranes of different pore sizes in selective layer have been prepared for experiments. The achieved results indicate that the ceramic membrane with selective layer of 20 nm pore size is appropriate for different flue gas conditions. The amount of recovered water augments with the increasing relative humidity of gas. When the temperature of flue gas reaches 70 °C, the amount of recovered water is above 1 L/m 2 h and the recovery ratio can be up to 55%. This method has great potentiality in the application of water recovery from flue gas in thermal power plants.

At present, the use of domestic and industrial solar energy is commonly divided into two parts: Photovoltaic and solar thermal utilization, but due to the high cost and long recovery cycle, are limited in their respective development in this field. As a high-efficiency solar energy utilization technology, photovoltaic/thermal attracts more and more attention. In this paper, a novel low concentration photovoltaic/thermal (LCPV/T) system with micro-channel heat pipe array was proposed. The environmental parameters and the inlet and the outlet temperature and output power were tested in this study. The efficiency of the system was up to 12.68% while at the same time thermal, electric and heat efficiency reached a value of 54.48%, 14.49% and 2.1% respectively, at the inlet temperature of 31 °C.

Herein, a nanotrough-like catalyst layer (NTCL) with low Pt loading and enhanced durability was developed directly as the cathode for proton-exchange membrane fuel cells (PEMFCs). Benefiting from the biomimetic architecture and ultrathin thickness, the mass transport of reactants and water management in the cathode are significantly enhanced. A peak power density of 0.936 W cm−2 is achieved with a Pt loading of 42 μg cm−2 in the cathode. Besides, the in-situ observation of water formation on the NTCL by the environmental scanning electron microscopy (ESEM) verified the efficient water management. Importantly, the Pt NTCL cathode is far more stable than the conventional electrode during the accelerated stress tests. The enhanced durability may be attributed to a self-healing mechanism, which involves Pt dissolution and re-deposition, endowing the NTCL with outstanding robustness. This work highlights a new approach to preparing and understanding nanostructured Pt electrodes with enhanced performance and durability for PEMFCs.

Backgroud : The outbreak of COVID-19 has brought unprecedented perils to human health and raised public health concerns in more than two hundred countries. Safe and effective treatment scheme is needed urgently. Objective : To evaluate the effects of integrated TCM and western medicine treatment scheme on COVID-19. Methods : A single-armed clinical trial was carried out in Hangzhou Xixi Hospital, an affiliated hospital with Zhejiang Chinese Medical University. 102 confirmed cases were screened out from 725 suspected cases and 93 of them were treated with integrated TCM and western medicine treatment scheme. Results : 83 cases were cured, 5 cases deteriorated, and 5 cases withdrew from the study. No deaths were reported. The mean relief time of fever, cough, diarrhea, and fatigue were (4.78±4.61) days, (7.22±4.99) days, (5.28± 3.39) days, and (5.28± 3.39) days, respectively. It took (14.84±5.50) days for SARS-CoV-2 by nucleic acid amplification-based testing to turn negative. Multivariable cox regression analysis revealed that age, BMI, PISCT, BPC, AST, CK, BS, and UPRO were independent risk factors for COVID-19 treatment. Conclusion : Our study suggested that integrated TCM and western medicine treatment scheme was effective for COVID-19., Graphical Abstract Image, graphical abstract