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The possibility of preparing bone substitutes in clinic is demonstrated in this study. With the addition of a small amount of water, the relative density of the calcium sulfate specimen prepared at room temperature became higher than 92%. This value is close to the density of the specimen prepared through conventional sintering at 1100 °C for 1 h. The biaxial strength of the specimen disc can reach 120 MPa. Densification is assisted by the hydration of calcium sulfate hemihydrate to dihydrate wherein coarse hemihydrate particles transformed to fine dihydrate dendrites. Strength is conferred by the entanglement of dendrites and microstructure refinement. The densified calcium sulfate disc remains degradable; its degradation rate in a phosphate buffer saline solution is ~1.6 wt%/day, and the rate remains steady for 28 days.

The energy density of a flexible all-solid-state supercapacitor (ASC) requires new electrode material with special structure and morphology as a prerequisite for its secured improvement. In this paper, a new morphological exploration of chicken nuggets-like core/shell NiCo2O4/MnO2 (NCM) nanosheet arrays on Ni foam was employed. The application of this special morphology aims to greatly improve the electrochemical performance of the cathode electrode. Additionally, Buckwheat Biochar (BBC) is utilized as the anode while the PVA/KOH thin film is prepared as the separator. The chicken nuggets-like core/shell NCM nanosheet arrays were obtained by a two-step hydrothermal method. A series of characterization methods were carried out to further support the core/shell's well-designed structure and precise composition. The tests exhibited excellent specific capacitance of 593.3 F g−1 at 5 mA cm−2 and outstanding cycling stability with a retention of 90% after 10000 cycles. Furthermore, the assembled NCM//BBC ASC device indicated a high specific capacitance (239 F g−1 at the current density of 5 mA cm−2), this is in due part of the unique architecture of NCM nanosheet arrays and interconnected special porous structure of the BBC and the thin film PVA/KOH. Hence, the assembled ASC device exhibited high energy density (an energy density of 58 Wh·kg−1 at 3263 W kg−1) and remarkable cycling stability.

There is limited knowledge on the potential impacts of electric vehicle (EV) deployment in developing countries to date. India is a rapidly industrializing country with a national policy to promote EVs, but does not have the waste management infrastructure to process battery waste. Through a model analysis for India, we projected that the sale of two-wheeler EVs will peak in 2030 at around 20 million units while the sale of four-wheeler EVs will steadily increase to 10 million units in 2050. Meanwhile, the volume of lead-acid battery waste is projected to peak in 2027, and lithium-ion battery waste from two-wheelers and four-wheelers will exceed 500 kilotons in 2044 and 1000 kilotons in 2050, respectively. Given these projections, it is imperative to create a safe environment for workers and surrounding communities, an extended producer responsibility (EPR) system and a national mechanism to track waste crimes related to batteries in the future.

Ciguatera poisoning (CP), arising from ciguatoxins produced by toxic dinoflagellate Gambierdiscus, is one of the most common food-borne diseases in the South Pacific. Climate change as well as its related events have been hypothesized to a higher abundance and wider presence of toxic dinoflagellates, hence a higher risk of the disease. Yet existing studies assessing the relationship between climate factors and CP are limited or based on old data. In this study, we used prewhitened cross-correlation analysis and auto-regressive integrated moving-average (ARIMA) modeling to develop predictive models of monthly CP incidence in Cook Islands and French Polynesia, two ciguatera-endemic regions in the South Pacific, utilizing the latest epidemiological data. Results reveal the significant time-lagged associations between the monthly CP incidence rate and several indicators relating to sea surface temperature (SST). In particular, SST anomaly is proven to be a strong positive predictor of an increased ciguatera incidence for both countries. If these time-lags can be supported by more investigations, it will allow health authorities to take appropriate actions, to limit or avoid an epidemic risk, especially on high-risk climate scenarios.

A self-assembled mesoporous silica sphere templating process was developed to create hierarchical continuous porous coral reef like N-doped carbon nanostructures on stainless steel meshes as bifunctional electrodes for ultrahigh performance lithium ion based energy storage devices. The coral reef like carbon nanostructure achieved a high specific surface area of 1229 m2 g−1 and a large specific pore volume of 2.21 cm3 g−1, without application of chemical activations. The electrode, when serving as an anode for lithium ion batteries (LIB) or lithium ion capacitors (LIC), delivered an ultrahigh specific capacity of 2058 mAh g−1 at 0.2 A g−1. If used as a cathode for LICs, it generated a high specific capacity of 125 mAh g−1 at 0.1 A g−1. The LICs assembled from using the electrode as both the cathode and anode, exhibited a high energy density of 145 Wh kg−1 at a power density of 1.4 kW kg−1 and maintained an energy density of 58 Wh kg−1 under an ultrahigh power density of 27.3 kW kg−1, among the top tie of the state-of-the-art LICs. The cycling stability of the LIC was outstanding with a 85% capacity retention after 5000 cycle operations at 5 A g−1. The hierarchical continuous porous coral reef like N-doped carbonaceous nanostructure provides micropores as micro-reservoirs of Li ions for local and fast Li ion intercalation/de-intercalation, edge N-doping for additional redox pseudo-capacitances, and large pore volumes to accommodate the volume expansion/shrinkage at the charge/discharge cycles and to offer fast mass transfer path for electrolyte ions, altogether leading to the successful applications as bifunctional electrodes for Li ion based energy storage devices.

A novel optical active fiber sensing technique based on the lasing wavelength demodulation for monitoring the human pulse and respiration is firstly proposed and experimentally demonstrated in this work. A section of no core fiber (NCF) with optimal length is selected to act as a sensing head, as well as a filter in a ring cavity to construct a kind of fiber laser. The respiration rate (RR) and pulse rate (PR) signals are obtained by measuring the shifts of lasing wavelength that caused by respiration-induced body tremor and pulse vibration. The experimental results show that the corresponding RR and PR parameters can be sensitively measured. The suitable wavelet transform is adopted to acquire the respiration and pulse signals in detail. Our proposed technique has the advantages of high sensitivity, compact sensing head, stable response, and capability to simultaneously achieve the information of multiple parameters related to the human health monitoring.

Although nonionic surfactants are relatively eco-friendly compared with cationic and anionic surfactants, few studies have investigated their application in modified clay. Herein we prepared organo-clay composites (OCCs) by mixing bentonite-enriched clay (BEC) with nonionic surfactants (Brij 30 and Igepal CO-890) and determined if these modifications would enable chickens to detoxify aflatoxin B1 (AFB1). For the first time, in situ three-dimensional (3-D) microstructures of modified BEC was characterized in suspension using transmission X-ray microscopy. Although X-ray diffraction patterns indicated the expansion in the spacing between planes of atoms (basal spacing) of surfactant-modified BEC, 3-D images indicated shrinkage in its microscale porous framework with increasing surfactant additions from 1 to 30 wt%. Such declining trends in porous dimensions caused by the dehydration in interlayer galleries of clays positively correlated with sorption amounts of AFB1 on OCCs. After chickens had consumed amended feeds for 11 weeks, AFB1 concentrations in liver, kidney, and plasma were significantly lower than in the control treatment. Thus, we suggest using BEC with 1 wt% surfactant addition, an amendment to chicken feeds, to detoxify AFB1. Modifying BEC with nonionic surfactants show the promise in mitigating AFB1 accumulation in chickens, which should improve food safety and reduce environmental contamination.

Nickel nanoparticles embedded nanoporous carbon (NPC/Ni) was fabricated via thermal treatment of metal organic framework precursors. Nickel particles were uniformly dispersed in the nanoporous carbon network under certain sintering temperature. Meanwhile, the obtained magnetic metal Ni could improve the electrical conductivity of carbon due to its graphitization catalysis on amorphous carbon. The obtained multiple interfaces, porous structures as well as tunable electrical conduction are all beneficial to the enhanced microwave absorption. The sample prepared at 700 °C exhibits nice microwave absorption capacity with the maximum reflection loss (RL) value of −39.4 dB and effective bandwidth of 4.2 GHz. In addition, the prepared sample exhibit huge potential as light absorber. When sample loading content decreases from 30 wt% to 25 wt%, its maximum RL value reaches −39.4 dB with an effective bandwidth of 4.2 GHz. This work not only demonstrates that the NPC/Ni composites are excellent absorbers with wide bandwidth, strong absorption, thin thickness and light weight, but also initiates a new pathway for artificially designed magnetic metal/dielectrics composites nanostructures with objective functionalities.

The liquid level fiber sensor with a measurement range of about 50 cm is fabricated through a kind of single-no-core-single mode (SNS) structure. It is found that the change of liquid level will only induce the wavelength shifts of the whole interference spectrum. The liquid level monitoring with sub-millimeter resolution can be achieved by the proposed discrete wavelength sampling method. In the experiment, the transmit interference spectrum is sampled by a tunable laser with a step of 0.5 nm, then constructed by cubic spline interpolation algorithm. The wavelength shifts can be obtained through a minimum variance demodulation algorithm. Experiment results exhibit an excellent linear response (R2 = 0.99993) and the high sensitivity response to different liquid refractive index (RI). And the sensitivity of the sensor is 23.38 pm/mm with the liquid RI of 1.3505. In particular, the sensing resolution of the liquid level can reach 0.5 mm. This anti-electromagnetic interference technique with such high resolution and large sensing range can find the promising applications of monitoring the left fuel in the aircraft tanker, the surface evaporation in the water resource cycle, etc.

Hierarchical automatic voltage control (AVC), which enables a secure and economic grid operation, has attracted a lot of global interest. This paper presents a novel control algorithm to address the wide-area AVC problem in modern power grids. The proposed approach is based on the recent advanced wide-area measurement system (WAMS) technologies. It aims to provide a reliable and effective coordinated voltage regulation (CVR) to support system security and avoid voltage fluctuation. An improved CVR model which can consider voltage stability margin (VSM) is proposed, in which a global indicator L is chosen as the constraint for the quantitative voltage stability index. An efficient iterative solving algorithm combining sequential linear programming (SLP) with fast-decoupled iteration is developed to solve the nonlinear optimization model. The new approach is capable of providing an effective voltage regulation over system reactive power sources. The efficacy of the proposed control strategy is validated by extensive simulation studies on several IEEE benchmark systems. The results demonstrate the superior system voltage profile/stability control performance of the proposed approach.

The emerging occurrence of thallium (Tl) in environments arouses the imposition of effective technology for its remediation. Due to the low solubility of Tl(III), the oxidation-precipitation of Tl(I) is considered as an promising removal method. Here, we recycled Al beverage can powder (AlCP) as the substitute for zero-valent Al to conduct the Fenton-like reaction for Tl(I) oxidation and subsequently induced the Tl(III) precipitation via the alkalinization at pH 9.5. The Tl(I) removal mechanisms in AlCP systems with amendments of Fe(III) or Fe(II) were determined in relation to its speciation for both dissolved and solid phases. Results showed that although additions of Fe(III)/Fe(II) prompted the Tl(I) oxidation as compared with the pure AlCP system, they were detrimental to the Tl removal upon the alkalinization. While the greatest removal efficiency was ~ 92% in AlCP/Fe(III)/Fe(II) systems, up to 99.8% of total Tl could be removed from the pure AlCP system. The Tl-XANES data indicated that although Tl(III) dominated the Tl inventory (92 – 95%) on all solids collected upon the alkalinization, it preferred to precipitate as stable Tl2O3 in pure AlCP system but as labile Tl(III) in AlCP/Fe(III)/Fe(II) systems, which might sorb on precipitated Al (hydr)oxides. Such sorbed Tl(III) is subject to reduction and the further dissolution, accounting for the lower removal efficiency for Tl in the presence of Fe(III)/Fe(II). This study corroborated the comparable Tl(I) removal efficiency of AlCP to that of state-of-the-art (nano)composites, providing a niche opportunity to give consideration to both interests in hazard remediation and the waste reduction/reuse.

We developed a model dual-light-responsive luminescent lanthanide supramolecular switch. A poly[2]pseudorotaxane was firstly constructed from a dilanthanide metal supramolecular assembly (EuTb· 1 EPO ) and an asymmetric diarylperfluorocyclopentene ( 2 ), in which EuTb· 1 EPO exhibits a satisfactory and tunable lanthanide luminescence, while the 2 moiety in the poly[2]pseudorotaxane displays a reversible photochromic process upon light irradiation with an excellent resistance to fatigue. By switching between closed-form and open-form states of 2 using ultraviolet and visible light irradiation alternately, the lanthanide luminescence of poly[2]pseudorotaxane can be quenched and rapidly recovered, that is, the poly[2]pseudorotaxane can be used as switchable controlling unit.

The anode configuration and gas management strategy are two of factors that affect the energy efficiency of a proton exchange membrane fuel cell. In order to improve the hydrogen utilization, unused hydrogen can be recirculated to the inlet using a pump. However, impurities diffusing from the cathode to the anode may cause the dilution of hydrogen in the anode. As a result, a gas management strategy is required for the anode recirculation configuration. In this preliminary study, a novel configuration for anode recirculation and a gas management strategy are proposed and verified by experiments. Two valves are installed in the recirculation line. The anode is operated in four modes (dead-end, recirculation, compression, and purge), and the real-time local current density (LCD) is monitored for gas management purposes. The results show that the LCD distribution is uniform during the recirculation mode and nonuniform during the dead-end and compression modes. With this configuration and gas management strategy, the cycle duration is increased by a factor of 6.5.

This study contributes to construct the mathematical model of hybrid dynamic economic emission dispatch (HDEED) considering renewable energy generation and propose a novel solving approach based on enhanced moth-flame optimization algorithm. Renewable energy power generation technology has an important impact on reducing pollutant emissions and promoting sustainable development. Therefore, this study aims to investigate the HDEED problem in consideration of renewable energy generation and improve the economic and environmental benefits of the power system. First, a moth-flame optimization algorithm based on position disturbance updating strategy (MFO_PDU) was proposed aiming at the non-convex, non-linear and high-dimensional characteristics of HDEED problem. Second, the mathematical model of HDEED on the basis of Wind-Solar-Thermal integrated energy was constructed, while taking into account the valve point effect, equality constraints and inequality constraints. Finally, three cases including test systems of different scales were formulated and employed to verify the proposed approach, and the compromise solution was determined through membership function. The results revealed that the fuel cost obtained by the MFO_PDU algorithm was 11.31%, 4.01% and 5.27% smaller than those of HHO, TSA and MFO algorithms for small-scale test system. Accordingly, the research outcomes contribute in reducing the fuel cost and pollutant emissions of power generation system, and further improving the utilization and penetration rate of renewable energy.