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The fabrication of poly(vinylidene fluoride) (PVDF) based foam with complicated three-dimensional (3D) geometry and excellent piezoelectric property remains great challenge worldwide. In this study, microcellular PVDF/multiwalled carbon nanotube (MWCNT) nanocomposite foaming part was fabricated by supercritical carbon dioxide (scCO 2) bead foaming technology. With the assistance of the ball milling, the good dispersion of MWCNT particles in PVDF matrix was achieved, which promoted the heterogeneous nucleation and enhancement effects of MWCNT on PVDF, resulting in the formation of more unique and denser cells, e.g. from 3.4 × 105 cells/cm3 of pure foam to 1.7 × 106 cells/cm3 of the composite foam when MWCNT content was 1.5%, and high compression strength, i.e. 3.1 MPa with 1.5% MWCNT at 10% compressive strain, about 1.1 MPa higher than that of pure foam. During the bead foaming process, the induced crystallization effect of MWCNT as well as the plasticizing and squeezing effect of scCO 2 on PVDF matrix contributed to the increase of the β-phase crystal in PVDF matrix, thus endowing the composite foaming part with good piezoelectric property, i.e. 6.5 V of output voltage under periodic compression, which lightened 4 LEDs and made the foaming part had wide potential application in smart electronic field. [ABSTRACT FROM AUTHOR]

In this paper, we study an on-line scheduling problem that is motivated by applications such as carpooling. The ride requests arrive on-line over-list and specify the service locations (among m locations). The goal is to determine a schedule that maximizes the number of satisfied requests using k servers. We consider two variants of the problem with respect to constraints on the service location: in the monotone service direction variant, the service locations of the requests assigned to a server must be monotonic; in the strict monotone service direction variant, the service locations must be strictly monotonic. We present lower bounds on the competitive ratio for both variants. For the monotone service direction variant, we give an optimal straightforward algorithm if k ≥ m and we prove that no deterministic on-line algorithm can achieve a constant competitive ratio if k < m. For the strict monotone service direction variant, we give a lower bound max ⁡ { 2 (m − 1) m , 1 } on the competitive ratio of barely deterministic algorithms if k > 2 , and a lower bound of max ⁡ { m 2 , 1 } if k ≤ 2. We propose a Balanced Interval Algorithm for the strict monotone service direction variant if k > 2 and report some numerical experiments to evaluate the efficiency of this algorithm. • We introduce two on-line algorithm problems with monotone service direction constraints which are applied for carpooling system. • We discuss the lower bounds and upper bounds of these two problems. • We propose a balanced interval algorithm and measure the algorithm performance with numerical experiments. [ABSTRACT FROM AUTHOR]

In this study, the effects of dicyclohexylcarbodiimide (DCC) and disodium succinate (DS) treatments on the pericarp browning (PB) development in postharvest longan were elucidated by measuring PB-related phenotypes and the metabolisms of antioxidants, membrane lipids, and phenolics. Compared to the control, DCC-treated longan displayed the higher levels of PB index, CMP, ROS, PA, DAG, and SFAs, the higher activities of POD, PPO, and MLMEs including PLD, PC-PLC, PI-PLC, lipase, and LOX, and the higher expression levels of DlPPO1 , DlPOD1 , and genes encoding MLMEs. In contrast, the lower levels of chromaticity values, pigments, TP, PC, PI, and USFAs, the lower activities of RSEs including SOD, CAT, and APX, the lower expression levels of genes encoding RSEs, and a lower non-enzymatic antioxidant capacity were also noted in DCC-treated longan. These results imply that the exacerbated PB induced by DCC was associated with the activation of MLMEs by up-regulating the expression of genes encoding MLMEs, which expedited the damage of cell membrane. This membrane damage was also regulated by the accelerated accumulation of ROS triggered by DCC. The increased membrane permeability after the damage prompted an enzymatic oxidation between phenol oxidase and phenolics. However, the opposite effect occurred in the DS-treated longan. • DCC accelerated pericarp browning, but DS delayed pericarp browning in fresh longan. • DCC lowed antioxidant ability, but DS raised antioxidant ability in longan pericarp. • DCC induced ROS accumulation in longan pericarp, but DS showed the reverse effects. • DCC promoted cell membrane damage of longan pericarp, but DS retarded this damage. • DCC raised phenolics oxidation in longan pericarp, but DS delayed this process. [ABSTRACT FROM AUTHOR]

• Cr,Er:YSGG crystal with thermal bonding and concave end-face is pumped by Xenon lamp. • Thermal distribution simulation shows thermal bonding can improve heat dissipation capability. • Thermal focal length indicates concave end-face can compensate thermal lens effect. • High single pulse energy of 3.48 J obtained for the concave thermal bonding Cr,Er:YSGG at 5 Hz. • Maximum energy of 1.155 J and slope efficiency of 3.65 % are achieved for the concave thermal bonding Cr,Er:YSGG at 20 Hz. We demonstrate the influence of thermal bonding and concave end-face on the 2.79 μm laser performance of Cr,Er:YSGG crystal. The simulation results of temperature distribution suggest that the two pure YSGG crystals bonded on the Cr,Er:YSGG as end-caps are beneficial to improve the heat dissipation capability. The experimental results of thermal focal length show that the thermal effects of un-bonding, planar thermal bonding, and concave thermal bonding Cr,Er:YSGG crystals are in descending tendency. The maximum output energies and slope efficiencies for concave thermal bonding Cr,Er:YSGG crystal are 3.480 J, 3.33 %@5 Hz; 2.126 J, 3.65 %@10 Hz; 1.384 J, 3.63 %@15 Hz; 1.155 J, 3.65 %@20 Hz, respectively, and the beam quality factors M x 2/ M y 2 are determined to be 7.68/8.63. The result is much better than the previous work, indicating that the xenon lamp pumped concave thermal bonding Cr,Er:YSGG crystal is a promising method to realize high energy laser output. All the results indicate that the thermal bonding and concave end-faces are promising methods to reduce the thermal effect and improve the laser performance of Cr,Er:YSGG crystal pumped by the xenon lamp. [ABSTRACT FROM AUTHOR]

We describe the epidemiology of 2 outbreaks of norovirus (GII) gastroenteritis in elementary schools in a city in eastern China using data from field investigations, pathogen testing, and face-to-face interviews. The transmission shows a point source type. In a case-control study, we identified airborne and person-to-person transmission as the source of the outbreaks. [Copyright &y& Elsevier]

The efficient removal of oil droplets and particles from volumes of a stable emulsified oil-contaminated polymer-flooding wastewater has been an interesting yet challenging research topic within the oilfield. In this work, a highly efficient composite flocculant (PAC-PSi-PDMDAAC) was prepared by modifying activated silicic acid onto polyaluminium chloride (PAC) through Si-O-Al bond firstly and then combined with polydimethyldiallyl ammonium chloride (PDMDAAC) by physical blending, the preparation conditions and the flocculation parameters that influence of the turbidity removal and oil removal were experimentally investigated. The optimal conditions are shown as follows: pH= 3.04, PAC/PSi = 5:1, PAC/PDMDAAC = 1:0.3. The characterization of composites were analyzed by Fourier infrared (FTIR), Thermogravimetry (Tg) and Static light scattering (SLS). The results revealed that PAC underwent the addition of PSi and PDMDAAC to form high-polymeric species. In addition, the formation of more denser flocs in wastewater treatment was affirmed with scanning electron microscope (SEM) analysis. The flocculation experiments results showed that the maximum turbidity removal rate and oil removal efficiency for polymer-flooding wastewater could reached 98.3% and 91.3% at dosage of 120 mg/L, respectively, and its flocculation efficiency was much better than that of flocculants (PAC, PAC-PSi and PAC-PDMDAAC), which confirmed the synergistic enhancement of performance of PAC by PSi and PDMDAAC. However, the Zeta potential results indicated that the maximum Zeta potential value of PAC-PDMDAAC treatment was not beneficial for oil and particles removal, which indicated the adsorption bridging effect of lager aggregates played a most significant role in the flocculation process. And this newly synthesized PAC-PSi-PDMDAAC would be a promising flocculant for polymer-flooding oily wastewater treatment to reduce oil and particulate matters. [Display omitted] [ABSTRACT FROM AUTHOR]

• High-quality Ho:YAP crystal was fabricated by the Czochralski method. • The structure, spectroscopy and J-O parameters of Ho:YAP were discussed. • For the first time, ∼3 μm CW laser was realized in single Ho-doped crystal host. • Maximum power of 176 mW and slope efficiency of 3.36% was obtained. We demonstrate the spectroscopy and mid-infrared laser performance on the Ho:YAP oxide crystal grown by the Czochralski method in detail. The crystal belongs to orthorhombic system of Pnmb (62) space group and shows high crystalline quality. The lifetimes of 5I 6 and 5I 7 levels are 0.412 and 4.485 ms, respectively. Particularly, under 1150 nm Raman fiber laser pumping, a 3.01 μm CW laser with a maximum power of 181 mW and slope-efficiency of 3.35% is achieved. The M2 factor of 1.35/1.37 indicates that the yield laser has excellent beam quality. The results reveal that the Ho:YAP crystal possesses great potential for developing efficient 3.0 μm mid-infrared lasers. [ABSTRACT FROM AUTHOR]

• Cascade Er:YSGG crystal pulsed lasers near 1.6 and 2.8 μm are realized at room temperature. • The slope efficiency of MIR laser increases to 4.2 % from 1.9 % by cascade process. • Four laser wavelengths of 2.793, 2.821, ∼2.860, 2.917 μm in Er:YSGG laser are discovered. • The cascade process can improve the MIR laser performance based on the Er:YSGG crystal. We demonstrate a pulsed cascade laser on LD end-pumped Er:YSGG crystal near 1.6 and 2.8 μm at room temperature for the first time. The slope efficiency of mid-infrared laser with the assistance of cascade process is significantly improved. Under the working frequency of 100 Hz and pump pulse width of 6 ms, a maximum power of 243 mW centered at 2.79 μm is achieved with increasing slope efficiency of 4.2 %, while the slope efficiency of non-cascade is only 1.9 %. Under high pump power, four laser wavelengths of 2.793, 2.821, ∼2.860, and 2.918 μm are discovered and the phenomenon is explained according to the Boltzmann factors. This work would be conducive to the exploration of pulsed cascade laser based on the Er:YSGG crystal. [ABSTRACT FROM AUTHOR]

This paper proposes an color image encryption algorithm using alternate chaotic mapping structure. Initially, we use the R, G and B components to form a matrix. Then one-dimension logistic and two-dimension logistic mapping is used to generate a chaotic matrix, then iterate two chaotic mappings alternately to permute the matrix. For every iteration, XOR operation is adopted to encrypt plain-image matrix, then make further transformation to diffuse the matrix. At last, the encrypted color image is obtained from the confused matrix. Theoretical analysis and experimental results has proved the cryptosystem is secure and practical, and it is suitable for encrypting color images. [ABSTRACT FROM AUTHOR]

Highlights: [•] We reprogrammed ICH patient's skin cells into iPSCs. [•] The iPSCs can differentiate into NES cells and neural cells in vitro. [•] Therapeutic effects of iPSC-derived NES cells in rat ICH model were observed. [•] The grafted NES cells differentiated into neural cells in the brain of ICH rats. [•] Functional improvement of ICH rat is partially due to neuronal replacement. [ABSTRACT FROM AUTHOR]

• Laser performance of LD side-pumped YSGG/Er:YSGG with concave end-faces is studied. • The laser rods with negative curvature radii of 250, 500 and 1000 mm are employed. • Highest power of 20.92 W with slope efficiency of 26.18% at 150 Hz is achieved. • 15.59 W at 500 Hz is obtained in rod with negative curvature radius of 500 mm. • Thermal bonding and concave end-faces can effectively improve laser performance. We demonstrate the laser performance of 970 nm LD side-pumped YSGG/Er:YSGG/YSGG thermal bonding crystal rods with negative curvature radii of 250, 500, and 1000 mm, respectively. The maximum average output powers of 20.04, 20.92, 17.02 W are achieved, corresponding to the slope efficiencies of 26.28%, 26.18%, 21.28%, and optical–optical efficiencies of 18.56%, 19.37%, 15.76%, respectively. The results of the laser performance and thermal focal length indicate that the negative curvature of 500 mm has an optimal effect on thermal lensing compensation. At the high repetition rate of 500 Hz, the average output power of 15.59 W is obtained. The beam quality factors of M x 2/M y 2 are calculated to be 3.37/3.34. These results can provide valuable references for promoting the development of 2.7–3 μm lasers. [ABSTRACT FROM AUTHOR]

• Raw soybean flour could be an alternative nitrogen source for economical production of Menaquinone-7 (MK-7) by a novel Bacillus velezensis ND strain (ND).was used as an economical nitrogen source for Menaquinone-7 (MK-7) production by a novel Bacillus velezensis ND strain (ND). • Liquid-state fermentation (LSF), biofilm-based fermentation (BF) and solid-state fermentation (SSF) for production of MK-7 were compared. • The expression level of genes involved in MK-7 biosynthesis were determined. In this study, a novel MK-7 producing bacterial strain, Bacillus velezensis ND, was isolated and characterized. Multiple low-cost substrates were used in Bacillus velezensis ND culture medium to reduce the MK-7 production cost, MK-7 concentration of 43.8 ± 2.8 mg/L was obtained using raw soybean flour by liquid-state fermentation (LSF). To improve the MK-7 production, LSF, biofilm-based fermentation (BF), and the solid-state fermentation (SSF) were compared. The highest MK-7 yield was achieved by SSF is 150.0 ± 4.9 mg/kg. The associated synthetic gene expressions under these three fermentation processes were investigated as well. The result indicated that the key genes menF , menH , and menG in the MK synthesis pathway are positively correlated with the increase of MK-7 biosynthesis. [ABSTRACT FROM AUTHOR]

The bio-waste slow pyrolysis process is assessed by four indicators to determine its energetic, exergetic, economic and environmental performance. The influence of the pyrolysis temperature (300–800 °C) on these parameters, but also on the biochar, bio-oil and gas production, is analysed. The biochar yield decreased 10.5% and the gas yield increased 17.2% between 300 and 800 °C. The bio-oil yield increased about 2.1% between 300 and 500 °C and decreased about 8% between 500 and 800 °C. Within the temperature range 300–800 °C, the H 2 , CO and CH 4 molar fractions increased 51.4, 6.6 and 0.3%, respectively. CO 2 content decreased about 58.3%. The exergy efficiency varied between 81.16 and 85.33% in this temperature range. The exergy-based economic factor revealed that 15.38–19.16% of the total cost was associated with the exergy destruction. The environmental impact was lower at higher temperatures. The recommended temperature range is 300–400 °C to produce biochar, and temperatures of over 700 °C to produce gas. When the interest focus is on the bio-oil, it is recommended to work close to 500 °C. Image 1 • Thermodynamic equilibrium model was applied to predict biochar, bio-oil and gas yields. • The bio-oil yield showed a maximum at 500 °C. • H 2 , CO and CH 4 contents in the pyrolysis gas increased with the pyrolysis temperature. • The exergy efficiency varied between 81.16 and 85.33%. • 15.38–19.16% of the total cost is associated with exergy destruction. [ABSTRACT FROM AUTHOR]

Substantial contact heat resistance exists among granules in traditional Moving Bed Indirect Heat Exchanger (MBIHE), leading to poor heat transfer. To address that issue, a novel MBIHE with embedded agitator is developed, where the agitation can induce granule migration. The migrating granule serves as heat carrier to "carry" its heat directly to heat transfer surface, which accordingly enhances the heat efficiency. Through simulating the agitating process based on Discrete Element Method, horizontal migrations of granules are observed. Migrativity (0 ≤ σ ≤ 1) is defined to describe the horizontal mixing intensity of granules, which in turn represents the ability of heat transfer enhancement by the granule migration. σ increases with the agitator's rotational number N r and approaches to 1 when N r > 60. Due to the granule migration, poor contact between granules and the lower part of heat transfer tube in a stagnant bed is addressed, and the heat transfer area is increased by ∼20%. A pilot-scale MBIHE with granule capacity of 60–120 kg/h is built to conduct heat recovery experiments. The heat transfer coefficient is enhanced by 2–3 times owing to the granule mixing in MBIHE, and the heat recovery efficiency is up to 60–80%. • Heat can be carried to the heat transfer surface directly by granule migration. • Heat transfer coefficient is enhanced by 2–3 times via embedded agitation. • Heat transfer area in granule side is increased by around 20% due to the agitation. • 60–80% of waste heat in high-temperature industrial granules can be recovered. [ABSTRACT FROM AUTHOR]

• The different fluidization modes in a 4 m long tube are experimentally investigated. • Fluidization phenomena differ with the tube length (from freely bubbling to slugging). • Results are used to validate a 3D simulation approach by the NEPTUNE_CFD code. • The effect of mesh refinement on the slugging behavior prediction is discussed. • It is demonstrated that experiments and simulation predictions are in good agreement. Long tubes with small internal diameter find increasing applications in indirect concentrated solar receivers using an Upflow Bubbling Fluidized Bed of Geldart-A powders as heat carrier. Although successfully demonstrated for tubes of 0.5 to 1 m length, longer tubes are required to increase the solar energy capture efficiency and capacity. The fluidization phenomena differ with the tube length, and freely bubbling fluidization will be transformed into slugging, thus hampering the heat transfer. The behavior of Geldart-A powders in tall tubes of small I.D. has not been extensively studied. The research experimentally investigated the different fluidization modes in a 4 m long tube, and demonstrated the occurrence of freely bubbling at the bottom section of the bed, and slugging from a bed depth in excess of about 1.25 m. Slug characteristics (frequency, length, velocity) were measured and correlated. The results were used to validate 3D numerical simulations based on an Euler-Euler approach in the NEPTUNE_CFD code applied to a fine mesh of 15,000,000 cells. A positive match between experimental and simulation results concerning frequency and velocity of large bubble structures was obtained. The effect of mesh refinement on the slugging behavior prediction was discussed. [ABSTRACT FROM AUTHOR]

In this study, ultrasound (US) disintegration was evaluated as a digestate treatment strategy. Digestate treatment is the physical, chemical or biological treatment and recirculation AD of the effluents of the anaerobic digesters (i.e., digestate) to the digester as supplementary feed to increase their utilization potential for energy conversion or green chemical production in post-valorization pathways. In this scope, semi-continuous small pilot scale manure digesters were operated in parallel with various operational settings. One of the digesters was fed by adding disintegrated digestate to an equal volume of fresh manure feed (recycle ratio of 1). The obtained results showed that US-assisted digestate treatment at 1500 kJ/kg TS specific energy input with 30 days of hydraulic retention time increased the methane production rate by 18%. The increased methane production rate was found to be related to the applied specific energy and organic loading rate. A basic cost-benefit analysis showed that the energy demand of the US disintegration at lab scale was higher than the energy that can be recovered from the additional biogas produced. • Ultrasound-assisted digestate treatment increases soluble COD of the digestate. • Higher methane production is correlated with the specific energy input of treatment. • Digestate treatment with lower intensity is favored for increased methane production. • Energy consumption of the US reactor exceeds energy gain from extra produced biogas. [ABSTRACT FROM AUTHOR]

Highlights • Four Cr,Er:YSGG crystal were processed with the size of Ø 3–6 mm × 105 mm. • A maximum pulse energy 1261 mJ operated at 5 Hz and 2.79 μm. • The formula of the thermal focal length is modified further. • Simulation results of the thermal focal lengths consist with the experiments well. Abstract We demonstrate the laser and thermal properties on the four Cr,Er:YSGG crystal rods with different diameters from 3 to 6 mm. A maximum pulse energy 1261 mJ operated at 5 Hz and 2.79 μm is obtained on the rod of 4 mm diameter, corresponding to electrical-to-optical efficiency of 1.53% and slope efficiency 1.82%, respectively. Combining with the electrical-to-optical efficiency and thermal distribution, the formula of the thermal focal length is modified further. The simulation results of the thermal focal length for four crystals with different diameters are in good consistence with the measurement values, suggesting the revised formula is accurate and effective to calculate the thermal focal length. [ABSTRACT FROM AUTHOR]

Gas-solid, gas-catalytic and physical applications in a fluidized bed require a strict control of the solids residence time and a limited back-mixing for a required conversion. Since conversion proceeds with residence time, this residence time and its distribution (RTD) are essential design parameters in fluidized bed modeling. The experiments of the present research investigate the use of a shallow cross-flow bubbling fluidized bed as reactor. A tracer stimulus response technique was used to determine the RTD, in a fluidized bed with and without internals. Experimental results were compared with fittings from several models. Although a cascade of perfectly mixed reactors or a plug flow with dispersion model can be applied, the latter is preferred, and the dispersion parameter, expressed as Peclet number, exceeds ∼25. The results are moreover used in a test case design of hexane devolatilization from rice bran cake. With the RTD model of the horizontal fluidized bed, and with batch kinetic experiments, the size of the desolventizer can be designed on the basis of the required residence time. The superficial fluidization velocity applied is normally 3–4 times U mf . A similar RTD-approach can be used for alternative physical processes (e.g. drying) and for chemical reactions (e.g. calcination of dolomite) provided kinetic data from batch experiments are known. [ABSTRACT FROM AUTHOR]

The key to achieve an economically more attractive concentrated solar power plant is to work at higher operating temperatures, allowing both higher power conversion efficiencies resulting in a smaller heliostat field for a given energy output, and higher temperature ranges in the storage tanks, with increased energy storage density and smaller size, hence less expensive. This fostered the development of using particle suspensions as heat transfer media. This paper presents a theoretical framework for the energy analysis of a particle-in-tube solar power plant, hybridized, with topping air-Brayton cycle turbine, and bottoming steam block. From studying the effects of essential design parameters on the energy efficiency, the heat transfer efficiency of the turbine air preheater is of paramount importance to increase the solar contribution within the hybrid concept, while the energy efficiency moreover increases by an optimum air-Brayton cycle turbine operation (mostly through the pressure ratio, less by the operating temperature). The overall efficiency of the concept varies from about 40% when using combined low and high pressure Brayton cycle turbines only, to over 48% in a fully combined air-steam concept. Energy efficiency findings are in agreement with the literature data. [ABSTRACT FROM AUTHOR]

Catalytic steam reforming of ethanol (CSRE) is an attractive mode of producing hydrogen as an environmentally-friendly energy carrier. Ethanol can be produced from first-generation fermenting of cheap carbohydrates (e.g. non-food cassava and agricultural residues), and second-generation fermenting of biomass. The catalytic conversion of ethanol requires an appropriate catalyst, operating temperature, and reaction time. Supported noble metal catalysts were previously used. The present work uses novel non-noble catalysts. The most efficient catalysts were impregnated in α-Al 2 O 3 and fully characterized. The catalytic experiments were conducted between 500 °C and 600 °C in either electrically-heated fixed bed reactors, or in a solar-heated fluidized bed reactor. The main reaction products were H 2 (approximately 5.5 mol H 2 /mol ethanol), CO, CO 2 and CH 4. Deactivation of the Co/α-Al 2 O 3 catalyst was not observed. Negligible amounts of acetone and acetaldehyde were detected. A maximum hydrogen yield of over 95% was achieved. Pilot-scale investigations were started. [Display omitted] • New perspectives for renewable energy-based hydrogen production by catalytically converting bio-ethanol in the presence of steam (CSRE). • Test the most promising catalysts in isothermal electrically heated furnaces, and in a concentrated solar reactor. • Over 30 successive hours of CSRE were assessed with approximately 5.5 mol H 2 /mol ethanol produced. • Further scale-up with maximum heat recovery, H 2 upgrading, and H 2 use in a solid oxide fuel cell (SOFC) and a 1 kg/h H 2 pilot facility. [ABSTRACT FROM AUTHOR]

Nanocelluloses, derived from various plants or specific bacteria, represent the renewable and sophisticated nano building blocks for emerging functional materials. Especially, the assembly of nanocelluloses as fibrous materials can mimic the structural organization of their natural counterparts to integrate various functions, thus holding great promise for potential applications in various fields, such as electrical device, fire retardance, sensing, medical antibiosis, and drug release. Due to the advantages of nanocelluloses, a variety of fibrous materials have been fabricated with the assistance of advanced techniques, and their applications have attracted great interest in the past decade. This review begins with an overview of nanocellulose properties followed by the historical development of assembling processes. There will be a focus on assembling techniques, including traditional methods (wet spinning, dry spinning, and electrostatic spinning) and advanced methods (self-assembly, microfluidic, and 3D printing). In particular, the design rules and various influencing factors of assembling processes related to the structure and function of fibrous materials are introduced and discussed in detail. Then, the emerging applications of these nanocellulose-based fibrous materials are highlighted. Finally, some perspectives, key opportunities, and critical challenges on future research trends within this field are proposed. [Display omitted] [ABSTRACT FROM AUTHOR]

• Concentrated Solar Power (CSP) is an electricity generation technology with high potential. • Gas/solid suspensions as heat transfer fluid can be used throughout the full CSP plant. • A novel Upflow Bubbling Fluidized Bed (UBFB) receiver concept is presented and assessed. • Hot particulate heat carriers foster the use of advanced thermodynamic cycles in the power block. • Some scale-up challenges must be resolved, but prospects and economy of the system are positive. Concentrated Solar Power (CSP) is an electricity generation technology that concentrates solar irradiance through heliostats onto a small area, the receiver, where a heat transfer medium, currently a fluid (HTF), is used as heat carrier towards the heat storage and power block. It has been under the spotlight for a decade as one of the potential or promising renewable and sustainable energy technologies. Using gas/solid suspensions as heat transfer medium in CSP has been advocated for the first time in the 1980′s and this novel concept relies on its possible application throughout the full CSP plant, i.e., in heat harvesting, conveying, storage and re-use, where it offers major advantages in comparison with the common heat transfer fluids such as water/steam, thermal fluids or molten salt. Although the particle suspension has a lower heat capacity than molten salts, the particle-driven system can operate without temperature limitation (except for the maximum allowable wall temperature of the receiver tubes), and it can also operate with higher hot-cold temperature gradients. Suspension temperatures of over 800 °C can be tolerated and achieved, with additional high efficiency thermodynamic systems being applicable. The application of high temperature particulate heat carriers moreover expands the possible thermodynamic cycles from Rankine steam cycles to Brayton gas cycles and even to combined electricity generating cycles. This review paper deals with the development of the particle-driven CSP and assesses both its background fundamentals and its energy efficiency. Among the cited systems, batch and continuous operations with particle conveying loops are discussed. A short summary of relevant particle-related properties, and their use as heat transfer medium is included. Recent pilot plant experiments have demonstrated that a novel bubbling fluidized bed concept, the upflow bubbling fluidized bed (UBFB), recently adapted to use bubble rupture promoters and called dense upflow fluidized bed (DUFB), offers a considerable potential for use in a solar power tower plant for its excellent heat transfer at moderate to high receiver capacities. For all CSP applications with particle circulation, a major challenge remains the transfer of hot and colder particles among the different constituents of the CSP system (receiver to storage, power block and return loop to the top of the solar tower). Potential conveying modes are discussed and compared. Whereas in solar heat capture, bubbling fluidized beds, particle falling films, vortex and rotary furnaces, among others, seem appropriate, both moving beds and bubbling fluidized beds are recommended in the heat storage and re-use, and examined in the review. Common to all CSP applications are the thermodynamic cycles in the power block, where different secondary working fluids can be used to feed the turbines. These thermodynamic cycles are discussed in detail and the current or future most likely selections are presented. Since the use of a back up fuel is recommended for all CSP systems, the hybrid operation with the use of alternative fuel back-up is also included in the review. The review research is concluded by scale-up data and challenges, and provides a preliminary view into the prospects and the overall economy of the system. Market prospects for both novel concentrated solar power are expected to be excellent. Although the research provided lab- and pilot-scale based design methods and equations for the key unit operations of the novel solar power tower CSP concept, there is ample scope for future development of several topics, as finally recommended. [ABSTRACT FROM AUTHOR]

The utilization of a large amount of anionic polyacrylamide (APAM) and sodium alkyl benzene sulfonate can induce the emulsified oil to acquire a stable emulsified colloid system in polymer flooding oily wastewater. However, for the traditional inorganic coagulants, such as polyaluminum, polyiron, etc., a relatively large number of bacteria will breed after oily sewage is treated for a specific period of time. Along these lines, in work, a new type of antibacterial polymeric aluminum silicate sulfate/sepiolite coagulant (PASS-H) was synthesized by using grafting hydrophobic antibacterial monomers in combination with coagulants composed of sepiolite as the base material for improving oily sewage purification. The structure and the surface morphology of the copolymer were systematically characterized, indicating that PASS-H was successfully synthesized. In addition, the coagulation performance of the polyaluminum silicate sulfate (PASS), modified sepiolite, and PASS-H during the treatment of polymer-containing oily wastewater was compared. In the coagulation experiments, PASS-H exhibited excellent turbidity, oil removal, and antibacterial properties. At 60 mg/L, the turbidity, oil removal rate, Zeta potentialand maximum floc size were 98%, 95%, 1.59 mv, and 26 μm, respectively. The mechanism of coagulation was thoroughly investigated based on the order of dosing, the tested water pH, Zeta potential, floc size, and the impact of the floc morphology on the coagulation. The coagulation behavior of the separate addition of the modified sepiolite and PASS was weaker than that induced by the one-time addition of PASS-H. Moreover, the enhanced charge neutralization, bridging adsorption, sweeping, and adsorption played a synergistic role in reducing the total amount of PASS-H and improving the coagulation ability. The introduction of antimicrobial monomers in PASS-H can also effectively inhibit the regeneration of sulfate-reducing bacteria (SRB) in the water. Finally, the residual turbidity and oil removal rate of the different coagulants were statistically analyzed. The extracted results have practical significance for both cost reduction and efficiency increase in large-scale applications. [Display omitted] [ABSTRACT FROM AUTHOR]

CaO and MgO are important industrial raw materials commonly produced by either the decomposition of calcium carbonate at about 900 °C, or the calcination of dolomite, a mixed calcium and magnesium carbonate, calcined either to MgO.CaCO 3 at about 750 °C, or to MgO.CaO at 900 °C. ln this research, the decomposition reaction of 104–147 μm dolomite and limestone particles was investigated, both without and with steam added to the reaction. A series of experiments was performed in terms of relevant parameters such as time, temperature and amount of H 2 O added. Reactants and reaction products were fully characterized and demonstrate the different morphology and specific surface area of the raw carbonate ores and the calcined oxides. Adding H 2 O during calcination has a significant positive effect. The calcination shows that steam can significantly accelerate the reaction rate, and reduce the decomposition temperature by ∼100 °C, thus reducing the cost of the decomposition by increasing the yield for a given reaction time, while also reducing the required sensible heat of the feedstock and combustion air. This ultimately reduces the amount of fossil fuel or alternative energy carriers, thus reducing the CO 2 footprint of the system. The improved operating conditions foster the use of concentrated solar calcination. The CO 2 footprint of the carbonate decomposition can be reduced by ∼4% in traditional kilns, and by as much as 20% if concentrated solar kilns are used. Both applications are currently investigated in pilot-scale operations. • Calcination of dolomite and limestone particles was studied, without and with adding steam. • Steam accelerates the reaction rate and reduces the calcination temperature by ∼100 °C. • Adding steam reduces the energy requirement, thus reducing the CO 2 footprint of the system. • CO 2 emissions are reduced by ∼4% in conventional kilns, and by ∼20% in solar kilns applications. [ABSTRACT FROM AUTHOR]

Background aims: Bone marrow-derived mesenchymal stromal cells (BMSCs) are a promising therapeutic option for treating Duchenne muscular dystrophy (DMD). Myogenic differentiation occurs in the skeletal muscle of the mdx mouse (a mouse model of DMD) after BMSC transplantation. The transcription factor bone morphogenic protein 4 (BMP4) plays a crucial role in growth regulation, differentiation and survival of many cell types, including BMSCs. We treated BMSCs with BMP4 or the BMP antagonist noggin to examine the effects of BMP signaling on the myogenic potential of BMSCs in mdx mice. Methods: We added BMP4 or noggin to cultured BMSCs under myogenic differentiation conditions. We then injected BMP4- or noggin-treated BMSCs into the muscles of mdx mice to determine their mvogenic potential. Results: We found that the expression levels of desmin and myosin heavy chain decreased after treating BMSCs with BMP4, whereas the expression levels of phosphorylated Smad, a downstream target of BMP4, were higher in these BMSCs than in the controls. Mdx mouse muscles injected with BMSCs pretreated with BMP4 showed decreased dystrophin expression and increased phosphorylated Smad levels compared with muscles injected with non-treated BMSCs. The opposite effects were seen after pretreatment with noggin, as expected. Conclusions: Our results identified BMP/Smad signaling as an essential negative regulator of promyogenic BMSC activity; inhibition of this pathway improved the efficiency of BMSC myogenic differentiation, which suggests that this pathway might serve as a target to regulate BMSC function for better myogenic differentiation during treatment of DMD and degenerative skeletal muscle diseases. [ABSTRACT FROM AUTHOR]

Highlights: [•] We assessed the therapeutic effect of iPSCs in experimental ICH rat. [•] Therapeutic effects of iPSCs in rat ICH model were observed. [•] The grafted iPSCs exhibited neural cell-specific biomarkers in the brain of ICH rats. [•] The levels of BDNF and VEGF were enhanced in the surrounding region of hematoma. [•] Functional improvement is partially due to neuronal replacement and neurophic factors. [ABSTRACT FROM AUTHOR]

Abstract: The anti-hyperlipidemic and antioxidant effects of haw pectic oligosaccharide (HPOS) were investigated using a model of hyperlipidemia induced by a high-fat diet in mice. HPOS significantly lowered the serum levels of total cholesterol (p <0.01) and triglycerides (p <0.05) and inhibited the accumulation of body fat in this model. It significantly enhanced the activity of superoxide dismutase to suppress oxidative reactions (p <0.01) and inhibited the synthesis and accumulation of malondialdehyde in serum (p <0.05). Thus, HPOS could be valuable in the development of nutritional and drug therapies to combat cardiovascular diseases. [Copyright &y& Elsevier]

Abstract: The biological collection efficiencies of the portable BioStage impactor and the Reuter centrifugal sampler (RCS) High Flow were investigated when measuring bacteria and fungi concentrations in five different environments in Shanghai, China. The devices were operated simultaneously at flow rates of 28.3 and 100L/min, respectively, in the same environment for 5min. Air samples were taken three times (morning, afternoon and evening) for culturable microorganisms and the entire experiments were repeated three times. In addition, the efficiencies of collecting the total bacteria by each of the samplers using different sampling time were quantified by quantitative polymerase chain reaction (qPCR). Gel electrophoresis was used to analyze the resulting qPCR products. The results indicate that, in general, the portable BioStage impactor yielded higher culturable bacterial and fungal concentrations than the RCS High Flow. Paired t-tests indicate that the differences were statistically significant in most cases. The qPCR tests show that the efficiencies of the two samplers depend on the sampling time and the environment. Among other factors, the particle bounce, the sampling time, and the desiccation play major roles in the observed sampling differences between the samplers. [Copyright &y& Elsevier]

• Discovery of a novel ω-transaminase with a large S pocket. • Regulation of RBS strength from the substrate side to ease the inhibition of key enzymes by intermediate products. • Comparison of catalytic preparation of l -ABA by different amino donor decomposition systems. ω-transaminase can mediate the asymmetric synthesis of chiral amines from aldehydes and ketones, which has important value in the synthesis of pharmaceutical intermediates. A novel ω-transaminase derived from Paracoccus pantotrophus (Pp TA) was obtained and cloned in E. coli BL21(DE3) for expression. The enzyme has high activity for 2-ketobutyric acid and benzylamine, as well as for aromatic compounds with side chains longer than ethyl aliphatic hydrocarbons. Molecular simulation showed that the S-pocket in the active center is larger than those of other ω-transaminases. Thereafter, a whole-cell catalytic system was designed to prepare l -2-aminobutyric acid by cascading Pp TA and other enzymes. By using several strategies (regulation of RBS intensity, by-product decomposition and cofactor self-sufficiency), whole-cell cascade biocatalysis showed a high ee value (> 99%) and high yield (71%) in one pot reaction. This study therefore proposes an efficient biocatalyst for the synthesis of unnatural amino acids with the participation of ω-transaminase. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of de-dusting hot gases is of increasing importance and growing interest, especially in advanced power generation systems and (petro-)chemical processes. High temperature de-dusting has advantages of exceeding dew points, enhancing energy recovery at higher temperatures, protecting the downstream heat recovery equipment from fouling or erosion, and potentially simplifying the overall process. Additional benefits are a reduced power consumption and the possibility to simultaneously capture gaseous pollutants (SO 2 , HCl) by the gas-solid reaction with injected alkali or by integrating catalysts to abate NO x , VOC (volatile organic compounds) and PCDD/F (polychlorinated dioxins and furans). Both porous ceramic and porous metal fiber filters have been proposed, with a growing preference for the rigid metal fibre filters. Either surface or depth filters are applied. The operation parameters of hot gas de-dusting by rigid fibre filters include the applied face velocity, the porosity of the filter fleece, its construction and the pulse jet cleaning performance. These parameters will be integrated into design equations to determine the operational pressure drop and filtration efficiency for a given gas flow rate, operating temperature, dust characteristics and pulse-jet cleaning mode. The broad range of potential applications of the filters prior to an energy recovery stage will be illustrated for petrochemical/chemical processes and for combustion and gasification. The expected durability and long-term successful operation necessitate a proper design of the filter media (porosity, pore size, thermal, mechanical and corrosion resistance). The appropriate fabrication materials will be evaluated, with stainless steel or high grade metal alloys recommended for use in the extreme conditions at high temperatures and pressures. Finally prospects and challenges are summarized. • Hot gas cleaning offers efficient pollutant control at a fair cost and fosters high efficiency energy recovery. • The design parameters and procedure using rigid filters will be presented. • Applications of such in petrochemical/chemical processes, and in the power generation are illustrated. • Various metal alloys such as Inconel®, Fecralloy® and Alloy HR can be used in extreme filtration conditions. [ABSTRACT FROM AUTHOR]

• The 25 at. % Er:YSGG crystal with higher homogeneity was grown by Cz method. • A maximum power of 11.81 W with slope efficiency of 10.49% is realized at 500 Hz. • The laser center wavelength is located at 2794 nm and M2 x /M2 y are 7.01/7.10. • The Er:YSGG rod with concave end faces could be operated at high repetition rate. We demonstrate the laser performance of high repetition frequency on a 970 nm laser diode (LD) side-pumped Er:YSGG crystal rod with concave end faces. The laser performance under different repetition rates and pulse widths was studied with an optimal cavity length. The maximum average output power of 11.81 W operated at a repetition frequency of 500 Hz and 2.794 μm was achieved, corresponding to the slope efficiency of 10.49%. In addition, the beam quality factors M2 x /M2 y of 7.01/7.10 and far-field divergences Θ x /Θ y of 9.15/9.18 mrad were also obtained under the high repetition frequency of 500 Hz. These results show that the LD side-pumped Er:YSGG laser crystal rod with concave end faces has the potential of being operated under high repetition frequency. [ABSTRACT FROM AUTHOR]

In this study, a novel, highly efficient and environmentally friendly ternary composites flocculant, namely, cationic starch-grafted-cationic polyacrylamide/graphene oxide (CS-g-CPAM/GO), was synthesized by ammonium persulfate initiation polymerization and condensation reaction. First, CS-g-CPAM was polymerized with cationic starch (CS), acrylamide (AM) and diallyl dimethyl ammonium chloride (DMDAAC), and CS-g-CPAM/GO was then synthesized by condensation reaction. The influence factors of graft polymerization were investigated, including total monomer concentration, initiator dosage, monomer mass ratio of m AM : m CS : m DMDAAC , post-polymerization temperature and post-polymerization time. The chemical structures and morphologies of the samples were characterized by Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermo-gravimetric and differential scanning calorimetry (TG-DSC), and scanning electron microscope (SEM). The CS-g-CPAM/GO was used to flocculate the oil sludge suspension, the effects of CS-g-CPAM/GO dosage, temperature and pH value on the flocculation performance were investigated, and the flocculation mechanism of CS-g-CPAM/GO was also analyzed. The results show that CS-g-CPAM/GO has outstanding flocculation effect, and CS-g-CPAM/GO flocculates oil sludge particles by adsorption bridging and charge neutralization in acidic and alkaline conditions. Image 1 • Novel CS-g-CPAM/GO flocculants were synthesized. • Chemical structures were characterized and analyzed. • Flocculation mechanism were summarized. [ABSTRACT FROM AUTHOR]