•The phosphate recovery process from wastewater was used as a material modification method.•HAP/C-S-H can remove Pb(II) from aqueous solution effectively at a wider pH range compared with ...C-S-H.•HAP/C-S-H provides a doubleenvironmental benefit for resource recovery and pollution control.•The compound mechanism of Pb(II) adsorption on HAP/C-S-H is proposed.
In this study, phosphate was recovered from wastewater by C-S-H, and its phosphate-rich product HAP/C-S-H was reused as a composite adsorbent to remove Pb(II) from aqueous solution. The samples were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), zeta potential and specific surface areas analysis. The adsorption of Pb(II) on C-S-H and HAP/C-S-H were investigated at different pH, ionic strength, contact time, initial concentration and temperature. The results showed that the adsorption capacities of Pb(II) were heavily dependent on pH and slightly dependent on ionic strength. The adsorption kinetics and adsorption isotherms were well described by pseudo-second-order model and Langmuir model, respectively, and the thermodynamic parameters indicated that the adsorption process was endothermic and spontaneous. The adsorption capacities of Pb(II) on C-S-H and HAP/C-S-H could reach 543.5 mg/g and 946.7 mg/g, respectively, when the pH was 5.0, the temperature was 298 K and the ionic strength was 0.01 M. All the results indicate that HAP/C-S-H, recovered from phosphate wastewater, is an effective material for Pb(II) removal from aqueous solution, providing double environmental benefits for resource recovery and pollution control.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Lead halide perovskite solar cells (PSCs) have shown unprecedented development in efficiency and progressed relentlessly in improving stability. All the achievements have been accompanied by diverse ...passivation strategies to circumvent the pervasive defects in perovskite materials, which play crucial roles in the process of charge recombination, ion migration, and component degradation. Among the tremendous efforts made to solve these issues and achieve high-performance PSCs, we classify and review both well-established and burgeoning passivation strategies to provide further guidance for the passivation protocols in PSCs, including chemical passivation to eliminate defects by the formation of chemical bonds, physical passivation to eliminate defects by strain relaxation or physical treatments, energetic passivation to improve the stability toward light and oxygen, and field-effect passivation to regulate the interfacial carrier behavior. The subtle but non-trivial consequences from various passivation strategies need advanced characterization techniques combining synchrotron-based X-ray analysis, capacitance-based measurements, spatially resolved imaging, fluorescent molecular probe, Kelvin probe force microscope,
etc.
, to scrutinize the mechanisms. In the end, challenges and prospective research directions on advancing these passivation strategies are proposed. Judicious combinations among chemical, physical, energetic, and field-effect passivation deserve more attention for future high-efficiency and stable perovskite photovoltaics.
This review systematically outlines chemical, physical, energetic and field-effect passivation for perovskite solar cells with their corresponding advanced characterization techniques.
The characterization of graphene oxide (GO) is a critical component of any GO based investigation. In this review, we attempt to highlight both the consistencies and inconsistencies of current ...approaches. Reviewing all of the GO literature would be an impossible task, so recent articles in two research areas are sampled: GO as a dispersant and GO as an emulsion stabilizer. Our goal is to summarize the current state of GO characterization and advocate for the development of more standard approaches to characterization.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Hybrid electrode materials are key for electrochemical performances of supercapacitors. In this work, vanadium pentoxide (V2O5) is grown on graphene by a microwave synthetic method, which is simple, ...rapid, energy-saving and efficient. Benefiting from the microwave synthetic method, uniform V2O5 nanoparticles with an approximately size of 20 nm are evenly dispersed on graphene. The resultant V2O5/graphene composites are assembled into symmetrical supercapacitors, exhibiting specific capacitances of 673.2 and 474.6 F g−1 at 1 and 10 A g−1, respectively, and 96.8% of capacitance retention after 10,000 cycles at 1 A g−1. Additionally, the assembled devices show outstanding energy density and power density characteristics (46.8 Wh kg−1 at 499.4 W kg−1 and 32.9 Wh kg−1 at 4746.0 W kg−1), which are superior than many similar devices. Furthermore, capacitive performances of V2O5/graphene composites with five different component ratios are thoroughly investigated and the charge storage mechanism is discussed.
Uniform V2O5 nanoparticles were grown on graphene by a rapid, energy-saving and efficient microwave synthetic method, which exhibited superior capacitive performances. Display omitted
•V2O5 was grown on graphene by a simple, rapid and efficient microwave synthetic method.•A series of V2O5/graphene composites with various component ratios were synthesized.•The V2O5/graphene composites exhibited excellent electrochemical performances.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The recent and ongoing outbreak of coronavirus disease (COVID‐19) is a huge global challenge. The outbreak, which first occurred in Wuhan City, Hubei Province, China and then rapidly spread to other ...provinces and to more than 200 countries abroad, has been declared a global pandemic by the World Health Organization. Those with compromised immune systems and/or existing respiratory, metabolic or cardiac problems are more susceptible to the infection and are at higher risk of serious illness or even death. The present review was designed to report important functional food plants with immunomodulatory and anti‐viral properties. Data on medicinal food plants were retrieved and downloaded from English‐language journals using online search engines. The functional food plants herein documented might not only enhance the immune system and cure respiratory tract infections but can also greatly impact the overall health of the general public. As many people in the world are now confined to their homes, inclusion of these easily accessible plants in the daily diet may help to strengthen the immune system and guard against infection by SARS‐CoV‐2. This might reduce the risk of COVID‐19 and initiate a rapid recovery in cases of SARS‐CoV‐2 infection.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Obstacle avoidance path planning is considered an essential requirement for unmanned aerial vehicle (UAV) to reach its designated mission area and perform its tasks. This study established a motion ...model and obstacle threat model for UAVs, and defined the cost coefficients for evading and crossing threat areas. To solve the problem of obstacle avoidance path planning with full coverage of threats, the cost coefficients were incorporated into the objective optimization function and solved by a combination of Sequential Quadratic Programming and Nonlinear Programming Solver. The problem of path planning under threat full coverage with no solution was resolved by improving the Bézier curve algorithm. By introducing the dynamic threat velocity obstacle model and calculating the relative and absolute collision cones, a path planning algorithm under multiple dynamic threats was proposed to solve the difficulties of dynamic obstacle prediction and avoidance. Simulation results revealed that the proposed Through-out method was more effective in handling full threat coverage and dynamic threats than traditional path planning methods namely, Detour or Cross Gaps. Our study offers valuable insights into autonomous path planning for UAVs that operate under complex threat conditions. This work is anticipated to contribute to the future development of more advanced and intelligent UAV systems.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•An effective hybrid system was applied for the successful treatment of key pollutants (HPG) in fracturing flowback fluid, and the synergistic index of the hybrid system was 20.45.•Various impacts of ...the decomposition rate by addition of scavengers had followed the order of EDTA-2Na < BQ < t-BuOH, therefore OH radicals had a dominant role in destructing the HPG.•A possible degradation pathway was proposed as the first report for the treatment of HPG by sono-Fenton system based on GC–MS product analysis.
An effective hybrid system was applied as the first report for the successful treatment of key pollutants (hydroxypropyl guar gum, HPG) in fracturing flowback fluid, and the synergistic index of the hybrid system was 20.45. In this regard, chemical oxygen demand (COD) removal ratio was evaluated with various influencing operating factors including reaction time, H2O2 concentration, Fe2+ concentration, ultrasonic power, initial pH, and temperature. The optimal operating parameters by single-factor analysis method were: the pH of 3.0, the H2O2 concentration of 80 mM, the Fe2+ concentration of 5 mM, the ultrasonic power of 180 W, the ultrasonic frequency of 20–25 kHz, the temperature of 39 ℃, the reaction time of 30 min, and the COD removal rate reached 81.15 %, which was permissible to discharge surface water sources based on the environmental standards. A possible mechanism for HPG degradation and the generation of reactive species was proposed. Results of quenching tests showed that various impacts of the decomposition rate by addition of scavengers had followed the order of EDTA-2Na < BQ < t-BuOH, therefore OH radicals had a dominant role in destructing the HPG. Based on the kinetic study, it was concluded that Chan Kinetic Model was more appropriate to describe the degradation of HPG. Identification of intermediates by GC–MS showed that a wide range of recalcitrant compounds was removed and/or degraded into small molecular compounds effectively after treatment. Under the optimal conditions, the sono-Fenton system was used to treat the fracturing flowback fluid with the initial COD value of 675.21 mg/L, and the COD value decreased to 80.83 mg/L after 60 min treatment, which was in line with the marine sewage discharge standard. In conclusion, sono-Fenton system can be introduced as a successful advanced treatment process for the efficient remediation of fracture flowback fluid.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
ObjectiveTo evaluate the sleep quality by self-reported questionnaires and polysomnography (PSG) among early kidney transplant recipients (KTRs) and to further explore their correlation.DesignThis ...was a prospective and cross-sectional analysis of the sleep characteristics among early kidney transplant recipients through an objective and subjective measurement.ParticipantsPatients with end stage renal disease on the transplant waiting list and after kidney transplantation were from a major organ transplantation center in Southern China (n = 83).Primary and secondary outcome measurementsObjective outcomes: PSG, noise and light. Subjective outcomes: demographic and clinical questionnaires, self-reported pain and Richards Campbell sleep questionnaire (RCSQ). After agreement with the informed consent, participants first completed demographic and clinical questionnaires, then worn the PSG within 5-10 days after kidney transplantation. Both noise, light and self-reported pain were monitored during sleep. After completion of PSG, the RCSQs were filled out next morning.ResultsA total of 298 patients were recruited and 83 participants were finally analyzed. The total RCSQ mean score was 51.0±18.9mm. The prevalence of poor sleep quality among early KTRs was 45.1%. Most of PSG characteristics were significantly correlated with their corresponding RCSQ items. And the total RCSQ scores were significantly correlated with the number of awakenings, the N2 percentage and the total sleep time (r = 0.79, 0.47 and 0.40, P<0.05) respectively. Noise was a statistically significant factor affecting the subjective sleep quality.ConclusionsThe sleep quality in early KTRs measured by both PSG and RCSQ exhibits consistency with each other. Sleep disruption always remains a substantial problem and is affected by self-reported noise among early KTRs. The RCSQ is easily applicable and interpretable so that it can be used for future daily clinical practice.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Phosphorus (P) deficiency in desert ecosystems is widespread. Generally, desert species may allocate an enormous proportion of photosynthetic carbon to their root systems to adjust their ...P-acquisition strategies. However, root P-acquisition strategies of deep-rooted desert species and the coordination response of root traits at different growth stages to differing soil P availability remains unclear. In this study, a two-year pot experiment was performed with four soil P-supply treatments (0, 0.9, 2.8, and 4.7 mg P kg
y
for the control, low-, intermediate-, and high-P supply, respectively). Root morphological and physiological traits of one- and two-year-old Alhagi sparsifolia seedlings were measured.
For two-year-old seedlings, control or low-P supply significantly increased their leaf Mn concentration, coarse and fine roots' specific root length (SRL), specific root surface area (SRSA), and acid phosphatase activity (APase), but SRL and SRSA of one-year-old seedlings were higher under intermediate-P supply treatment. Root morphological traits were closely correlated with root APase activity and leaf Mn concentration. One-year-old seedlings had higher root APase activity, leaf Mn concentration, and root tissue density (RTD), but lower SRL and SRSA. Two-year-old seedlings had higher root APase activity, leaf Mn concentration, SRL and SRSA, but a lower RTD. Root APase activity was significantly positively correlated with the leaf Mn concentration, regardless of coarse or fine roots. Furthermore, root P concentrations of coarse and fine roots were driven by different root traits, with root biomass and carboxylates secretion particularly crucial root traits for the root P-acquisition of one- and two-year-old seedlings.
Variation of root traits at different growth stages are coordinated with root P concentrations, indicating a trade-off between root traits and P-acquisition strategies. Alhagi sparsifolia developed two P-activation strategies, increasing P-mobilizing phosphatase activity and carboxylates secretion, to acclimate P-impoverished in soil. The adaptive variation of root traits at different growth stages and diversified P-activation strategies are conducive to maintaining the desert ecosystem productivity.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This letter presents a 5–6‐GHz dual‐mode power amplifier (PA) realized for further enhanced licensed assisted access application of downlink transmission. The output matching network with multiple ...harmonic traps and the wideband AM‐PM compensation technique are used in the design. To achieve high linear output power with less variation in the wide frequency range, different bias voltages of the first stage PA are set for dual‐mode operation. In the range 5–6 GHz, the PA delivers > 30 dBm saturated output power and reaches 24.4–24.8 dBm linear power at −35 dBc adjacent channel leakage ratio.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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