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Conventional Al-air battery has many disadvantages for miniwatt applications, such as the complex water management, bulky electrolyte storage and potential leakage hazard. Moreover, the self-corrosion of Al anode continues even when the electrolyte flow is stopped, leading to great Al waste. To tackle these issues, an innovative cotton-based aluminum-air battery is developed in this study. Instead of flowing alkaline solution, cotton substrate pre-deposited with solid alkaline is used, together with a small water reservoir to continuously wet the cotton and dissolve the alkaline in-situ. In this manner, the battery can be mechanically recharged by replacing the cotton substrate and refilling the water reservoir, while the thick aluminum anode can be reused for tens of times until complete consumption. The cotton substrate shows excellent ability for the storage and transportation of alkaline electrolyte, leading to a high peak power density of 73 mW cm−2 and a high specific energy of 930 mW h g−1. Moreover, the battery discharge capacity is found to be linear to the loading of pre-deposited alkaline, so that it can be precisely controlled according to the mission profile to avoid Al waste. Finally, a two-cell battery pack with common water reservoir is developed, which can provide a voltage of 2.7 V and a power output of 223.8 mW. With further scaling-up and stacking, this cotton-based Al-air battery system with low cost and high energy density is very promising for recharging miniwatt electronics in the outdoor environment.

Atmospheric CO2 concentrations are soaring due to the continued use of fossil fuels in energy production, an anthropogenic activity that is playing a leading role in global warming. Thus, research aimed at the capture and conversion of CO2 into value-added products, such as cyclic carbonates, is booming. While CO2 is an abundant, cheap, non-toxic, and readily accessible C1 feedstock, its thermodynamic stability necessitates the development of highly efficient catalysts that are able to promote chemical reactions under mild conditions. In this work, a novel mesoporous poly(ionic liquid) with dual active sites was synthesized through a facile method that involves co-polymerization, post-synthetic metalation, and supercritical CO2 drying. Due to a high density of nucleophilic and electrophilic sites, the as-prepared poly(ionic liquid), denoted as P2D-4BrBQA-Zn, offers excellent performance in a CO2 cycloaddition reaction using epichlorohydrin as the substrate (98.9% conversion and 96.9% selectivity). Moreover the reaction is carried out under mild, solvent-free, and additive-free conditions. Notably, P2D-4BrBQA-Zn also efficiently promotes the conversion of various other epoxide substrates into cyclic carbonates. Overall, the catalyst is found to have excellent substrate compatibility, stability, and recyclability.

Electrochemical CO2 reduction (CO2RR) over molecular catalysts is a paramount approach for CO2 conversion to CO. Herein, we report a novel phthalocyanine-derived catalyst synthesized by a two-step method with a much improved electroconductivity. Furthermore, the catalyst contains both Ni–N4 sites and highly dispersed metallic Ni nanoclusters, leading to an increased CO2RR currents by two folds. Isotope labelling study and in situ spectroscopic analysis demonstrate that the existence of metallic Ni nanoclusters is the key factor for the activity enhancement and can shift the CO2RR mechanism from being electron transfer (ET)-limited (forming ∗COO−) to concerted proton-electron transfer (CPET)-limited (forming CO).

In the conversion process of syngas-to-C2 species, the OH species are inevitably produced accompanying the production of key intermediates CHx(x = 1–3), traditionally, the function of surface OH species is generally accepted as the hydrogenating reactive species. This work for the first time proposed and confirmed the assisted catalytic mechanism of surface OH species that performed as the promoter for syngas-to-C2 species on Cu-based catalysts. DFT and microkinetic modeling results reveal that the produced OH species accompanying the intermediates CHx production on the MCu (M = Co, Fe, Rh) catalysts can stably exist to form OH/MCu catalysts, on which the presence of surface OH species as the promoter not only presented better activity and selectivity toward CHx(x = 1–3) compared to MCu catalysts, but also significantly suppressed CH3OH production, providing enough CHx sources to favor the production of C2 hydrocarbons and oxygenates. Correspondingly, the electronic properties analysis revealed the essential relationship between the electronic feature of OH/MCu catalysts and catalytic performance, attributing to the unique electronic micro−environment of the catalysts under the interaction of surface OH species. This new mechanism is called as OH-assisted catalytic mechanism, which may be applied in the reaction systems related to the generation of OH species.

Synthesizing nitrogen (N)-containing molecules from biomass derivatives is a new strategy for production of this kind of chemicals. Herein, for the first time we present the synthesis of N-substituted aryl pyrroles via reductive amination/cyclization of levulinic acid (LA) with primary aromatic amines and hydrosilanes (e.g., PMHS) over CsF, and a series of N-substituted aryl pyrroles could be obtained in good to excellent yields at 120 °C. The mechanism investigation indicates that the reaction proceeds in two steps: the cyclization between amine and LA occurs first to form intermediate 5-methyl-N-alkyl-1,3-dihydro-2H-pyrrolones and their isomeride (B), and then the chemo- and region-selective reduction of intermediates take place to produce the final products. This approach for synthesis of N-substituted aryl pyrroles can be performed under mild and green conditions, which may have promising applications.

Effective and robust electrocatalysts are mainly based on innovative materials and unique structures. Herein, we designed a flakelike cobalt phosphide-based catalyst supporting on NiCo2O4 nanorods array, which in-situ grew on the nickel foam (NF) current collector, referring as N–Co2P/NiCo2O4/NF electrode. By optimizing the microstructure and electronic structure through 3D hierarchy fabrication and nitrogen doping, the catalyst features with abundant electrochemical surface area, favorable surface wettability, excellent electron transport, as well as tailored d band center. Consequently, the as-prepared N–Co2P/NiCo2O4/NF electrode exhibits an impressive HER activity with a low overpotentials of 58 mV at 10 mA cm−2, a Tafel slop of 75 mV dec−1, as well as superior durability in alkaline medium. This work may provide a new pathway to effectively improve the hydrogen evolution performance of transition metal phosphides and to develop promising electrodes for practical electrocatalysis.

This work includes fabrication and electrical characterization of Metal/Interlayer/Semiconductor (MIS) structures with methyl violet organic film on p-InP wafer. Metal(Ag)/ Interlayer (methyl violet =MV)/Semiconductor(p-InP) MIS structure presents a rectifying contact behavior. The values of ideality factor (n) and barrier height (BH) for the Ag/MV/p-InP MIS diode by using the current-voltage (I-V) measurement have been extracted as 1.21 and 0.84 eV, respectively. It was seen that the BH value of 0.84 eV calculated for the Ag/MV/p-InP MIS structure was significantly higher than the value of 0.64 eV of Ag/p-InP control contact. This situation was ascribed to the fact that the MV organic interlayer increased the effective barrier height by influencing the space charge region of inorganic semiconductor. The values of diffusion potential and barrier height for the Ag/MV/p-InP MIS diode by using the capacitance-voltage (C-V) measurement have been extracted as 1.21 V and 0.84 eV, respectively. The interface-state density of the Ag/MV/p-InP structure was seen to change from 2.57×1013 eV-1cm-2 to 2.19×1012 eV-1cm-2.

Owing to the advantages of high operating voltage, environmental benignity, and low cost, potassium-based dual-ion batteries (KDIBs) have been considered as a potential candidate for large-scale energy storage. However, KDIBs generally suffer from poor cycling performance and unsatisfied capacity, and inactive components of conductive agents, binders, and current collector further lower their overall capacity. Herein, we prepare coral-like carbon nanowires (CCNWs) doped with nitrogen as a binder-free anode material for K+-ion storage, in which the unique coral-like porous nanostructure and amorphous/short-range-ordered composite feature are conducive to enhancing the structural stability, to facilitating the ion transfer and to boosting the full utilization of active sites during potassiation/de-potassiation process. As a result, the CCNW anode possesses a hybrid K+-storage mechanism of diffusive behavior and capacitive adsorption, and stably delivers a high capacity of 276 mAh g-1 at 50 mA g-1, good rate capability up to 2 A g-1, and long-term cycling stability with 93 % capacity retention after 2000 cycles at 1 A g-1. Further, assembling this CCNW anode with an environmentally benign expanded graphite (EG) cathode yields a proof-of-concept KDIB, which shows a high specific capacity of 134.4 mAh g-1 at 100 mA g-1, excellent rate capability of 106.5 mAh g-1 at 1 A g-1, and long-term cycling stability over 1000 cycles without negligible capacity loss. This study provides a feasible approach to developing high-performance anodes for potassium-based energy storage devices.

Co–N–C is a promising oxygen electrochemical catalyst due to its high stability and good durability. However, due to the limited adsorption ability improvement for oxygen-containing intermediates, it usually exhibits inadequate catalytic activity with 2-electron pathway and high selectivity of hydrogen peroxide. Herein, the adsorption of Co–N–C to these intermediates is modulated by constructing heterostructures using transition metals and their derivatives based on d-band theory. The heterostructured nanobelts with MoC core and pomegranate-like carbon shell consisting of Co nanoparticles and N dopant (MoC/Co–N–C) are engineered to successfully modulate the d band center of active Co–N–C sites, resulting in a remarkably enhanced electrocatalysis performance. The optimally performing MoC/Co–N–C exhibits outstanding bi-catalytic activity and stability for the oxygen electrochemistry, featuring a high wave-half potential of 0.865 V for the oxygen reduction reaction (ORR) and low overpotential of 370 mV for the oxygen evolution reaction (OER) at 10 mA cm−2. The zinc air batteries with the MoC/Co–N–C catalyst demonstrate a large power density of 180 mW cm−2 and a long cycling lifespan (2000 cycles). The density functional theory calculations with Hubbard correction (DFT + U) reveal the electron transferring from Co to Mo atoms that effectively modulate the d band center of the active Co sites and achieve optimum adsorption ability with “single site double adsorption” mode.

Plasma methods are given significant attention in the context of conditioning the producer gas derived from biomass gasification. The goal of this work is to present the impact of hydrogen on the other producer gas compounds during microwave plasma valorization. These compounds include main producer gas components (CO, CO2, CH4, N2) and minor impurities (tar compounds, H2S and NH3). The results prove a beneficial impact of hydrogen addition on the conversion of CH4 and toluene, increasing it from ca. 68%–95% and ca. 97%–100%, respectively. Additionally, the presence of hydrogen changes the distribution of the products, inhibiting soot and aromatics production and promoting C2 compounds. In the case of CO2, the conversion increases from ca. 18%–63% when compared to nitrogen plasma, with CO being the resulting product. The presence of hydrogen inhibits H2S conversion and does not affect CO and NH3

In molecular communications, the direct detection of signaling molecules may be challenging due to a lack of suitable sensors and interference in the environment. Motivated by research in molecular biology, we investigate an indirect detection mechanism using chemical reactions between the signaling molecules and a molecular probe to produce an easy-to-measure product at the receiver. We consider two implementations of the proposed detection mechanism, i.e., unrestricted probe movement and probes restricted to a volume around the receiver. The reaction-diffusion equations describing the concentrations of the reactant and product molecules in the system are non-linear and coupled, and cannot be solved in closed form. Therefore, we develop an efficient iterative algorithm by discretizing the time variable and solving for the space variables of the equations in each time step. Our results show that the concentrations of the product molecules and the signalling molecules share a similar characteristic over time, i.e., a single peak and a long tail. The peak and tail values of the product molecule concentration can be controlled by choosing probes with suitable parameters. By carefully choosing the molecular probe and optimizing the decision threshold, the BER can be improved significantly and outperform that of a direct detection system., 13 pages, 11 figures, 1 table. This journal version was submitted in April 2022 to the IEEE for possible publication. A part of this article was presented at the IEEE Wireless Communications and Networking Conference 2020 and stored in the previous version on arXiv

In this study, CO₂ conversion to acetate and CH₄ was achieved in a flow-through laboratory-scale microbial electrosynthesis (MES) cell composed of a 3D conductive polylactic acid (cPLA) lattice cathode with electrodeposited metal electrocatalyst coatings. The MES cell with a bare cPLA cathode showed the poorest performance with the lowest H₂ and CH₄ production rates and low Coulombic efficiency. This was ascribed to a poor electrocatalytic activity of cPLA towards H₂ production and high electrode resistivity. When the cPLA electrode was modified with metal coatings, the CH₄, acetate and H₂ production rate increased significantly, with the following trend: cPLA < Ni < NiFe < NiFeMn. The better performance of the metal-coated cPLA in terms of CH₄ production was attributed to the lower electrical resistance, enhanced H₂ production and enhanced electron transfer between the cathode and the biofilm. At the cell potential of 2.8 V, the best-performing NiFeMn cPLA cathode showed stable production of CH₄ (50 ± 6 mL d⁻¹), acetate (185 ± 27 mg d⁻¹), and H₂ (545 ± 175 mL d⁻¹) at close to 100% Coulombic efficiency.

Defect-engineered carbon materials have been emerged as promising electrocatalysts for oxygen reduction reaction (ORR) in metal-air batteries. Developing a facile strategy for the preparation of highly active nanocarbon electrocatalysts remains challenging. Herein, a low-cost and simple route is developed to synthesize defective graphene by pyrolyzing the mixture of glucose and carbon nitride. Molecular dynamics simulations reveal that the graphene formation is ascribed to two-dimensional layered feature of carbon nitride, and high compatibility of carbon nitride/glucose systems. Structural measurements suggest that the graphene possesses rich edge and topological defects. The graphene catalyst exhibits higher power density than commercial Pt/C catalyst in a primary Zn-air battery. Combining experimental results and theoretical thermodynamic analysis, it is identified that graphitic nitrogen-modified topological defects at carbon framework edges are responsible for the decent ORR performance. The strategy presented in this work can be can be scaled up readily to fabricate defective carbon materials.

Synthesizing ring structure aviation fuels from biomass-derived platform molecules is challenging, especially for bridged ring structure aviation fuels which are typically achieved from fossil-derived chemicals. Herein, we report the synthesis of a series of ring structure biofuels in two steps by a combination of a solvent-free Michael-cyclization reaction and a hydrodeoxygenation (HDO) reaction from lignocellulose-derived 5,5-dimethyl-1,3-cyclohexanedione. These biofuels are obtained with high overall yields up to 90%, which exhibit high densities of 0.81 g cm−3-0.88 g cm−3 and high volumetric neat heat of combustion (VNHOC) values of 36.0 MJ L−1-38.6 MJ L−1. More importantly, bridged-ring structure hydrocarbons can also be achieved in two steps by a combination of a Robinson annulation reaction and an HDO reaction to afford the final products at high overall yields up to 90%. The bridged-ring structure products have comparable high densities and high VNHOC values to the best artificial fuel JP-10 (0.94 g cm−3 and 39.6 MJ L−1). The results demonstrate a promising way for the synthesis of high-density aviation fuels with different fuel properties at high yields.

3D flower-like hierarchical mesoporous Bi4O5I2/MoS2 Z-scheme layered heterojunction photocatalyst was fabricated by oil bath and hydrothermal methods. The heterojunction with narrow band gap of ∼1.95 eV extended the photoresponse to near-infrared region, which showed obvious photothermal effect due to the introduction of MoS2 with broad spectrum response. MoS2 nanosheets were anchored onto the surface of flower-like hierarchical mesoporous Bi4O5I2 nanosheets, thereby forming efficient layered heterojunctions, the solar-driven photocatalytic efficiency in degradation of highly toxic dichlorophenol and reduction of hexavalent chromium was improved to 98.5% and 99.2%, which was ∼4 and 7 times higher than that of the pristine Bi4O5I2, respectively. In addition, the photocatalytic hydrogen production rate reached 496.78 μmol h-1 g-1, which was ∼6 times higher than that of the pristine Bi4O5I2. The excellent photocatalytic performance can be ascribed to the promoted photothermal effect, as well as, the formation of compact Z-scheme layered heterojunctions. The 3D flower-like hierarchical mesoporous structure provided adequate surface active-sites, which was conducive to the mass transfer. Moreover, the high stability of the prepared photocatalyst further promoted its potential practical application. This strategy also provides new insights for fabricating layered Z-scheme heterojunctions photocatalysts with highly photothermal-photocatalytic efficiency.

The Ru-catalyzed carbonylation of alkenes with CO2 as a C1 surrogate and imidazole chlorides as the promotor is investigated by a combination of computational and experimental study. The conversion rate of CO2 to CO is positively correlated with the efficiency of both hydroesterification and hydroformylation, which is found facilitated in the presence of chloride additives with a decreasing order of BmimCl ∼ B3MimCl > BmmimCl ∼ LiCl. Taking the hydroesterification with MeOH as a representative example, BmimCl bearing C–H functionality at the C2 site of the cation assists the reduction of CO2 to CO as a hydrogen donor medium, with the anion and cation acting in a synergistic fashion. Subsequent insertion of CO2 into the formed Ru–H bond with the assistance of chloride anion produces the Ru–COOH species, which ultimately accelerates the activation of CO2.

Energy conversion technologies like fuel cells and metal-air batteries require oxygen reduction reaction (ORR) electrocatalysts with low cost and high catalytic activity. Herein, N-doped carbon spheres (N-CS) with rich micropore structure have been synthesized by a facile two-step method, which includes the polymerization of pyrrole and formaldehyde and followed by a facile pyrolysis process. During the preparation, zinc chloride (ZnCl2) was utilized as a catalyst to promote polymerization and provide a hypersaline environment. In addition, the morphology, defect content and activity area of the resultant N-CS catalysts could be regulated by controlling the content of ZnCl2. The optimum N-CS-1 catalyst demonstrated much better catalytic activity and durability towards ORR in alkaline conditions than commercial 20 wt% Pt/C catalysts, of which the half-wave potential reached 0.844 V vs. RHE. When applied in the Zn-air batteries as cathode catalysts, N-CS-1 showed a maximum power density of 175 mW cm-2 and long-term discharging stability of over 150 h at 10 mA cm-2, which outperformed 20 wt% Pt/C. The excellent performance could be due to its ultrahigh specific surface area of 1757 m2 g-1 and rich micropore channels structure. Meanwhile, this work provides an efficient method to synthesize an ultrahigh surface porous carbon material, especially for catalyst application.

Activated red mud (RM) has been proved to be a promising base material for the selective catalysis reduction (SCR) of NOx. The inherent low reducibility and acidity limited its low–temperature activity. In this work, molybdenum oxide, tungsten oxide, and cerium oxide were used to reconfigure the redox sites and acid sites of red mud based catalyst. When activated red mud was reconfigured by cerium-tungsten oxide (Ce–W@RM), the NOx conversion kept above 90% at 219–480 °C. The existence of Ce3+/Ce4+ redox electron pairs provided more surface adsorbed oxygen (Oα) and served as a redox cycle. Positive interactions between Ce, W species and Fe oxide in red mud occurred, which led to the formation of unsaturated chemical bond and promoted the activation of adsorbed NH3 species. WO3 and Ce2(WO4)3 (formed by solid–state reaction between Ce and W species) could provide more Bronsted acid sites (W–O modes of WO3, W O or W–O–W modes of Ce2(WO4)3). CeO2 species could provide more Lewis acid sites. The Langmuir–Hinshelwood (L-H) routes and Eley-Rideal (E-R) routes occurred in the low-temperature SCR reaction on the Ce–W@RM surface. NH4+ species on Bronsted acid sites, NH3 species on Lewis acid sites, bidentate nitrate and bridging nitrate species were key active intermediates species.

A novel strategy was developed to fabricate FeNx-doped carbon quantum dots (Fe-N-CQDs) to detect Cu2+ ions selectively as a fluorescence probe. The Fe-N-CQDs were synthesized by an efficient electrolysis of a carbon cloth electrode, which was coated with monoatomic iron-anchored nitrogen-doped carbon (Fe-N-C). The obtained Fe-N-CQDs emitted blue fluorescence and possessed a quantum yield (QY) of 7.5%. An extremely wide linear relationship between the Cu2+ concentration and the fluorescence intensity was obtained in the range from 100 nM to 1000 nM (R2 = 0.997), and the detection limit was calculated as 59 nM. Moreover, the Fe-N-CQDs demonstrated wide range pH compatibility between 2 and 13 due to the coordination between pyridine nitrogen and Fe3+, which dramatically reduced the affection of the protonation and deprotonation process between H+ and Fe-N-CQDs. It is notable that the Fe-N-CQDs exhibited a rapid response in Cu2+ detection, where stable quenching can be completed in 7 s. The mechanism of excellent selective detection of Cu2+ was revealed by energy level simulation that the LUMO level of Fe-N-CQDs (−4.37 eV) was close to the redox potential of Cu2+, thus facilitating the electron transport from Fe-N-CQDs to Cu2+.

Biodegradable magnesium (Mg) and its alloy show huge potential as temporary bone substitute due to the favorable biocompatibility and mechanical compatibility. However, one issue deserves attention is the too fast degradation. In this work, mesoporous bioglass (MBG) with high pore volume (0.59 cc/g) and huge specific surface area (110.78 m2/g) was synthesized using improved sol-gel method, and introduced into Mg-based composite via laser additive manufacturing. Immersion tests showed that the incorporated MBG served as powerful adsorption sites, which promoted the in-situ deposition of apatite by successively adsorbing Ca2+ and HPO42−. Such dense apatite film acted as an efficient protection layer and enhanced the corrosion resistance of Mg matrix, which was proved by the electrochemical impedance spectroscopy measurements. Thereby, Mg based composite showed a significantly decreased degradation rate of 0.31 mm/year. Furthermore, MBG also improved the mechanical properties as well as cell behavior. This work highlighted the advantages of MBG in the fabrication of Mg-based implant with enhanced overall performance for orthopedic application.

Establishing highly effective charge transfer channels in carbon nitride (g-C3N4) to enhance its photocatalytic activity is still a challenging issue. Herein, the delaminated 2D Ti3C2 MXene nanosheets were employed to decorate the P-doped tubular g-C3N4 (PTCN) for engineering 1D/2D Schottky heterojunction (PTCN/TC) through electrostatic self-assembly. The optimized PTCN/TC exhibited the highest hydrogen evolution rate (565 μmol/h/g), which was 4.3 and 2.0 -fold higher than pristine bulk g-C3N4 and PTCN, respectively. Such enhancement may be primarily attributed to the phosphorus heteroatom doped and unique structure of 1D/2D g-C3N4/Ti3C2 Schottky heterojunction, enhancing the light-harvesting and charges’ separation. One-dimensional pathway of g-C3N4 tube and built-in electric field of interfacial Schottky effect can significantly facilitate the spatial separation of photogenerated charge carriers, simultaneously inhibit their recombination via Schottky barrier. In this composite, metallic Ti3C2 was served as electrons sink and photons collector. Moreover, ultrathin Ti3C2 flake with exposed terminal metal sites as a co-catalyst exhibited higher photocatalytic reactivity in H2 evolution compared to carbon materials (such as reduced graphene oxide). This work not only proposed the mechanism of tubular g-C3N4/Ti3C2 Schottky junction in photocatalysis, but also provided a feasible way to load ultrathin Ti3C2 as a co-catalyst for designing highly efficient photocatalysts.

Diphenyl carbonate (DPC) is one of the versatile carbonates, and is often used for the production of polycarbonates. In recent years, the catalytic synthesis of DPC has become an important topic but the development of a highly active metal-free catalyst is a great challenge. Herein, a series of ionic liquids-SBA-15 hybrid catalysts with different functional groups have been developed for the synthesis of DPC under solvent-free condition, which are effective and clean instead of the metal-containing catalysts. It is found that in the presence of [SBA-15-IL-OH]Br catalyst, methyl phenyl carbonate (MPC) conversion of 80.5% along with 99.6% DPC selectivity is achieved, the TOF value is thrice higher than the best value reported by using transition metal-based catalysts. Moreover, the catalyst displays remarkable stability and recyclability. This work provides a new idea to design and prepare eco-friendly catalysts in a broad range of applications for the green synthesis of carbonates.

Hydrogen energy has long been recognized as a clean alternative to conventional fossil fuels, which can be applied in a wide range of transportation and power generation applications. The rational design and engineering of high-performance and robust catalysts for hydrogen evolution reaction (HER) shows not a great significance but a challenge for efficient electrochemical water splitting. Herein, a new type of Ni-based Ni-ABDC precursor has been obtained, which leads to the formation of N-doped porous carbon nanomaterials uniformly coated with well-proportioned bimetallic AgNi alloys via a stepwise strategy. To their credit, all samples of AgNi/NC-X are structurally calcined from the pristine AgNi-ABDC-X by tuning the different concentration of AgNO3, which means all of them maintain the vermicelli-like morphology compared with Ni-ABDC. The series of AgNi/NC-X materials can be regarded as effective electrocatalysts for HER both in acidic and alkaline media, but an acid-leaching phenomenon is observed. Among them, the as-prepared AgNi/NC-2 exhibits a low overpotential of 103 mV at the current density of 10 mA cm−2 and decent durability with a high retention rate of 90.9% after 10 h in 1.0 M KOH electrolyte. The compelling HER properties of AgNi/NC-2 can be attributed to the synergistic effect between the hierarchical carbon materials, partial N-doping and abundant AgNi alloys. Meanwhile, this study provides a practicable method for the development of efficient HER electrocatalysts for energy applications, which can be conveniently prepared through the reasonable introduction of active components in the crystalline inorganic-organic precursors.

Along with the environmental pollution, the scarcity of clean water seriously threatens the sustainable development of human society. Recently, the rapid development of solar evaporators has injected new vitality into the field of water purification. However, the industry faces a considerable challenge of achieving comprehensive purification of ions, especially the efficient removal of mercury ions. In this work, we introduce an ideal mercury-removal platform based on facilely and cost-effectively synthesized polysulfide nanoparticles (PSNs). Further development of PSN-functionalized reduced graphene oxide (PSN-rGO) aerogel evaporator results in achieving a high evaporation rate of 1.55 kg m−2 h−1 with energy efficiency of 90.8% under 1 sun. With the merits of interconnected porous structure and adsorption ability, the photothermal aerogel presents overall purification of heavy metal ions from wastewater. During solar desalination, salt ions can be rejected with long-term stability. Compared with traditional water purification technologies, this highly efficient solar evaporator provides a new practical method to utilize clean energy for clean water production.

In this work, Ag/Bi5O7I nanocomposite was prepared and firstly applied in piezo/photocatalytic reduction of N2 to NH3 and methyl orange (MO) degradation. Bi5O7I was synthesized via a hydrothermal-calcination method and shows nanorods morphology. Ag nanoparticles (NPs) were photo deposited on the Bi5O7I nanorods as electron trappers to improve the spatial separation of charge carriers, which was confirmed via XPS, TEM, and electronic chemical analyses. The catalytic test indicates that Bi5O7I presents the piezoelectric-like behavior, while the loading of Ag NPs can strengthen the character. Under ultrasonic vibration, the optimal Ag/Bi5O7I presents high efficiency in MO degradation. The degradation rate is determined to be 0.033 min−1, which is 4.7 folds faster than that of Bi5O7I. The Ag/Bi5O7I also presents a high performance in piezocatalytic N2 fixation. The piezocatalytic NH3 generation rate reaches 65.4 μmol L−1 g−1 h−1 with water as a hole scavenger. The addition of methanol can hasten the piezoelectric catalytic reaction. Interestingly, when ultrasonic vibration and light irradiation simultaneously act on the Ag/Bi5O7I catalyst, higher performance in NH3 generation and MO degradation is observed. However, due to the weak adhesion of Ag NPs, some Ag NPs would fall off from the Bi5O7I surface under long-term ultrasonic vibration, which would greatly reduce the piezoelectric catalytic performance. This result indicates that a strong binding force is required when preparing the piezoelectric composite catalyst. The current work provides new insights for the development of highly efficient catalysts that can use multiple energies.

A series of CoPd/KIT-6 bimetallic catalysts with various Co:Pd molar ratios at different calcination temperatures were prepared and used for the direct synthesis of H2O2 from H2 and O2. These catalysts were characterized by nitrogen adsorption-desorption, low and wide-angle X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), elemental mapping and energy-dispersive X-ray (EDX) methods. It was found that the particle size, electronic interactions, morphology, and textural properties of these catalysts as well as their catalytic activity in the reaction of H2 with O2 were affected by Co addition and different calcination temperatures. Also, the results showed that while the H2O2 selectivity depends on Pd2+ species, the H2 conversion is related to Pd0 active sites. Among these catalysts, CoPd/KIT-6 calcined at 350 °C (CoPd/KIT-350 catalyst) showed the best catalytic activity with 50 % of H2O2 selectivity and 51 % conversion of H2.

The ability to correctly choose a suture material, appropriately suture a wound and ligate a structure are fundamental in any surgical speciality. These are index skills that a junior surgeon must master before progressing on to more complex procedures. This article discusses factors to consider when choosing suture material, techniques for closure of a wound, and knots used to ligate a structure. With use of minimally invasive techniques now widespread, the article also discusses laparoscopic methods for performing such tasks.

Adsorptive removal of heavy metal ions from wastewater is very important, and the key is the development of efficient sorbents. In this work, oxygenated alkynyl carbon materials (OACMs) were synthesized via mechanochemical reaction of CaC2 and a carbonate (CaCO3, Na2CO3, or NaHCO3) at ambient temperature. The resultant OACMs are micro mesoporous carbon nanomaterials with high specific area (>648 m2 g−1), highly crosslinked texture, and rich alkynyl and oxygenated groups. The OACMs exhibit excellent Hg(II) adsorption due to the soft acid-soft base interaction between alkynyl and Hg(II), and OACM-3 derived from CaC2 and NaHCO3 has the saturated Hg(II) adsorbance of 483.9 mg g−1 along with good selectivity and recyclability. The adsorption is mainly chemisorption following the Langmuir mode. OACM-3 also shows high adsorbance for other heavy metal ions, e.g. 256.6 mg g−1 for Pb(II), 232.4 mg g−1 for Zn(II), and 198.7 mg g−1 for Cu(II). This work expands the mechnochemical reaction of CaC2 with carbonates and possibly other oxyanionic salts, provides a new synthesis approach for functional alkynyl carbon materials with excellent adsorption performance for heavy metal ions, as well as a feasible approach for CO2 resource utilization.

Aqueous zinc-air battery (ZAB) has attractive features as the potential energy storage system such as high safety, low cost and good environmental compatibility. However, the issue of dendrite growth on zinc metal anodes has seriously hindered the development of ZAB. Herein, the N-doped carbon cloth (NC) prepared via magnetron sputtering is explored as the substrate to induce the uniform nucleation of zinc metal and suppress dendrite growth. Results show that the introduction of heteroatoms accelerates the migration and deposition kinetics of Zn2+ by boosting the desolvation process of Zn2+, eventually reducing the nucleation overpotential. Besides, theoretical calculation results confirm the zincophilicity of N-containing functional group (such as pyridine N and pyrrole N), which can guide the nucleation and growth of zinc uniformly on the electrode surface by both promoting the redistribution of Zn2+ in the vicinity of the surface and enhancing its interaction with zinc atoms. As a result, the half-cell assembled with magnetron sputtered carbon cloth achieves a high zinc stripping/plating coulombic efficiency of 98.8% and long-term stability of over 500 cycles at 0.2 mA cm-2. And the Coulombic efficiency reached about 99.5% at the 10th cycle and maintained for more than 210 cycles at a high current density of 5.0 mA cm-2. The assembled symmetrical battery can deliver 220 plating/stripping cycles with ultra-low voltage hysteresis of only 11 mV. In addition, the assembled zinc-air full battery with NC-Zn anode delivers a high special capacity of about 429 mAh gZn-1 and a long life of over 430 cycles. The effectiveness of surface functionalization in promoting the transfer and deposition kinetics of Zn2+ presented in this work shows enlightening significance in the development of metal anodes in aqueous electrolytes.

Covalent organic frameworks (COFs) are nanoporous crystalline polymers with densely conjugated structures. This work discovers that imine-linked COFs exhibit remarkable photodegradation efficiency to azo dyes dissolved in water. Visible light generates different types of radicals from COFs, and superoxide radicals break N N bonds in dye molecules, resulting in 100% degradation of azo dyes within 1 h. In contrast, these dyes cannot be degraded by conventionally used photocatalysts, for example, TiO2. Importantly, the COF photocatalysts can be recovered from the dye solutions and re-used to degrade azo dyes for multiple times without loss of degradation efficiency. This work provides an efficient strategy to degrade synthetic dyes, and we expect that COFs with designable structures may use as new photocatalysts for other important applications.

Graphene oxide (GO) is regarded as a promising candidate to construct solar absorbers for addressing freshwater crisis, but the easy delamination of GO in water poses a critical challenge for practical solar desalination. Herein, we improve the stability of GO membranes by a self-crosslinking poly (ionic liquid) (PIL) in a mild condition, which crosslinks neighbouring GO nanosheets without blemishing the hydrophilic structure of GO. By further adding carbon nanotubes (CNTs), the sandwiched GO/CNT@PIL (GCP) membrane displays a good stability in pH = 1 or 13 solution even for 270 days. The molecular dynamics simulation results indicate that the generation of water nanofluidics in nanochannels of GO nanosheets remarkably reduces the water evaporation enthalpy in GCP membrane, compared to bulk water. Consequently, the GCP membrane exhibits a high evaporation rate (1.87 kg m−2 h−1) and displays stable evaporation rates for 14 h under 1 kW m−2 irradiation. The GCP membrane additionally works very well when using different water sources (e.g., dye-polluted water) or even strong acidic solution (pH = 1) or basic solution (pH = 13). More importantly, through bundling pluralities of GCP membrane, an efficient solar desalination device is developed to produce drinkable water from seawater. The average daily drinkable water amount in sunny day is 10.1 kg m−2, which meets with the daily drinkable water needs of five adults. The high evaporation rate, long-time durability and good scalability make the GCP membrane an outstanding candidate for practical solar seawater desalination.

This study aimed to control lesser grain borer Rhizopertha dominica via using of Zingier officinale (ginger) and Helianthus annuus (sunflower) oils as protectant of Tritium spp. The inhibition rates were 38.00, 28.98, 22.67 and 4.60% respectively when the wheat treated by 0.5, 1, 1.5and 2% of sunflower oil while the inhibition rates were 35.50, 28.00, 7.25 and 3.25% respectively when the wheat treated by the same concentrations of Z. officinale oil. The damage assessments were decreased while increasing the concentration of the oils, the H. annuus oil is more protectant than Z . officinale oil in 2%. Approximately the two plant oils caused same damage percentage when the wheat treated by 1% during storage. To sum up, the results strengthen the possibility of using the plant oils for the management this insect. http://dx.doi.org/10.25130/tjps.23.2018.026

The objective of this work to review about interaction of different food additives with Haemoglobin (Hb) and Myoglobin (Mb) proteins. Food additives are the important components which are added in food to preserve its flavour, color, appearance along with its taste. Mb and Hb interacts with numerous food dyes at varying conditions. In this study we will use various spectroscopic techniques like fluorescence spectroscopy, UV–Visible spectroscopy, Rayleigh light scattering (RLS), fluorescence resonance energy transfer (FRET), circular dichroism (CD)alongwithtransmissionelectronmicroscopy (TEM)andmoleculardockingtocharacterize the binding consequences of Mb and Hb. Proteinaggregationisthedistinctivepropertyrelatedtohumanbody. Deformationofprotein along with its aggregation leads to vast conformational change in human body and leads to several blood related (anemia, leukemia) andneurodegenerativediseaseslikeParkinson’sandAlzheimer’s. Foodadditivesaretoxictohumansaswellastoenvironment. Sothe aim of this study to find out the methods for detection of such diseases along with its cure as well as methods to release these toxic dyes via interaction of additives with Hb & Mb.

The parsing of floorplans has been an issue for a long time in automated document processing and with algorithmic methods until recent years. This problem has also improved output with the emergence of convolutionary neural networks (CNN). The job here is to obtain spatial and geometrical data from floorplans as accurately as possible. The aim of this project is to extract the most information from a floor plan image around instance segmentation models like Cascade Mask R-CNN. A new style of key point CNN is being implemented to supplement the segmentation to find correct corner positions. Then the resulting segmentation is combined in a post-processing stage. With a mean IoU of 72.7 percent versus 57.5 percent, the resulting segmentation scores surpass the existing baseline of the CubiCasa5k floorplan data base. Moreover, for almost every class, the mean IoU for each class is increased. Cascade Mask R-CNN has also been shown to be better suited to this role than Mask R-CNN.

Gesture Recognition which is an inevitable part of human computer interaction is an ever evolving active research area. This has been in use under varied applications like smart home systems, sign language recognition, augment reality and in device controls. The acquisition of hand gestures are usually through optical sensors, in this work a radar based hand gesture data set is used for classifying the gestures. Micro doppler signatures were used as the input to the model. Radar dataset has fewer data samples compared to optical based data sets. The proposed work uses separable convolutional neural networks model which does depth wise convolution followed by point wise convolution to reduce overfitting effect of the training data. The proposed model was built in such a way that the model is capable of classifying any unseen data without exactly mimicking the training samples. The proposed model has achieved 94.56% as the testing accuracy which is certainly better than the previous work on this Dop Net data set. Moreover the model has also minimized the computational hours of the model using separable convolutions.

Gold was considered as universal remedies for diseases like inflammation, infections, etc in 19th century. Later in 20th century Robert Koch discovered Gold complex Potassiumdicyanidoaurate(I) showing activity against Mycobacterium tuberculosis, later the treatment was proved to be ineffective subsequently. Further in 1985 Auranofin (Gold salt) was introduced for the treatment of Rheumatoid Arthritis, which had to be taken orally and believed to be the major discovery till injectable gold came into existence. The function of drugs based on gold is majorly related to Rheumatoid arthritis but engrossment has bent towards the adequacy of Gold compounds for anti cancer activities. The review article summarizes the current research on Gold complexes and their biological activities against cancer as well as in case of RA.

The synthesis of metallic Nanoparticles (NPs) has gathered utmost interest over the past decades thank to their distinctive properties that build them applicable in several fields further as including science and technology. This main methods utilized in their synthesis are non-environmental friendly. This review paper describes the green methods within the synthesis of biogenic NPs further as their mechanisms involving various plant extracts which are non toxic, environment friendly and value effective. The natural plant extracts contains metabolites like flavonoids, terpenoids, polyphenols, alkaloids, etc which acts as both reduction and stabilization agents for synthesizing biogenic NPs with desired shape and size. During this review paper the employment of assorted plant extracts additionally the employment of bacteria, fungi, proteins within the biogenic synthesis of NPs has been delineated shortly. Ultimately the importance and applications of biogenic NPs has also been expressed.

Content Based Image Retrieval is ever growing technology for many applications such as medical, remote sensing, social media search engines and surveillance monitoring, etc,. Representing image content with appropriate features is tedious task using traditional low level feature extraction methods. Deep learning models achieved high precision in classification and object detection algorithms by extracting automated high level feature extraction process. This paper proposed a hybrid feature extraction technique by combining the high level features and low level features to improve the robustness of the feature vector. The proposed model used pre-trained Googlenet model as feature extractor and combined with Gabor multiscale texture features. The final feature vector will be used for retrieving the relevant image data from the large scale image dataset. It has achieved the precision of 91 percent which shows better than state of art methods.

The unconventional machining processes are popular in machining the difficult to cut type complex contour/ profile. The key parameters are to be machined with care as they directly affects the function and non key dimensions are machined with other than consideration of functional aspect, like design, passage. That means accuracy is less important in those dimensions but finish is to be good. So the machining of engineering materials does not always require optimizing parameters based on multiple responses. This investigation focuses on the sensitiveness of Wire EDM of 12X18H10T - Stainless Steel and identifying the parameters contribution and establish mathematical model to predict values without trial. An austenitic alloy 12X18H10T - Stainless Steel exhibits its inherent mechanical properties even when it expose to extremely high temperature. Ithas potential application in aerospace engine components manufacturing. This investigation utilized the Taguchi L9 experiential Design with factors of Pulse off Time, Wire Tension, Pulse on Time, and Wire Feed Rate. This study aims to examine Maximize the rate of machining with Taguchi approach in the process of Wire EDM of 12X18H10T - Stainless Steel and establish a mathematical model to predict the highly influencing parameter(s) for desired rate of machining.

Electric discharge machining (EDM) routehas capability of machining hard materials. Even intricate shapes can be machined by this process. Traditional machining routes develop machining issues like tool wear and pitiable surface finish. It can be overcome by the EDM process. The objective of this work is to prepare AA6351-10wt%Al2O3-5wt%Gr composites through stir casting process. The manufactured composites were machined via EDM route and their machining characteristics material removal rate (MRR) and surface roughness (SR) were studied via Taguchi process. The results display that for MRR current is the major influencing parameter and for SR voltage is the foremostpersuading parameter.

Prediction of the facts about any topic always sounds fascinating. It becomes more important and useful when it can predict the facts about healthcare information. In computer science, machine learning techniques/models can be used to predict important health care facts, further the study of the sentiments related to health care information can also play a significant role in the generation of important information. There are many international and national organizations like United States Centers for Disease Control and Prevention (CDC), World Health Organization (WHO), etc. that publish important healthcare data. These data sets can be used to predict important facts about the disease. Further, the datasets related to sentiments of the people like tweets on Twitter, posts on Facebook, and blogs are useful to study the sentiments of the people on a particular topic. Sentiments related to health care information, diseases, and epidemics are very useful. The study of these sentiments can help make better prediction systems and to generate fruitful health care facts. Further, the real datasets related to infectious diseases like COVID-19 can be used for regression analysis for making predictions regarding the upcoming cases. In this paper, we have presented a survey on the application of different machine learning techniques, that are used in the classification and regression analysis related to health care predictions and the study of sentiments. We have presented a review of major research studies related to healthcare between the years 2010 to 2020.

According to the latest news, the 3rd Generation cooperation Project has been taken the inventiveness of creating an interworking architecture involving cellular and WLAN as an additional feature to the cellular network requirements of 3GPP. This article provides an overview of an interworking infrastructure that allows mobile operators to provide the public WLAN dependent entrance service to various 3GPP network subscribers. The enabling features include 3GPP membership reuse, network availability, authentications relying on 3GPP systems, security keys agreement, USIM /SIM card authorization, user data service access and routing, as well as end-user paying. The function of interworking is accomplished without setting any particular 3GPP specifications for the new WLAN entrance networks, but instead by depend on existing features available in the traditional WLAN entrance networks centered on the IEEE 802.11 principles. In this paper, authors have focused on two key aspects of MTC devices, as currently discussed in 3GPP-Release 10. These are named as “the control of subscriptions” and the “congestion/overload control of the network”. A new solution is proposed for the latter one based on the handling of the bulk signals.

Chitosan (CS) is a natural and biopolymer that are suitable biomedical properties such as; biocompatibility, non-toxicity, biodegradability and bioactive polymer that’s reason with a very large application (fabrication of biomedical scaffolds, implants). Some of the biocompatible thermoplastic polymers (PLA, PEEK, PLGA, PE, PP, PMMA, PET and etc.) are most widely used in biomedical field as per their properties from last two decades. Poly-vinyl chloride (PVC) thermoplastic polymer are most widely used in medical field but there are some limitations of their uses. For enhancement of PVC thermoplastic polymers properties sometimes add some bioactive and biocompatible fillers or other bioactive thermoplastic polymers. In this review paper try to link and discussed about the possible reinforcement CS in PVC thermoplastic polymer for biomedical applications.

Many organizations view themselves as market driven in this digitalized society, where the decision making depends solely on the customer feedbacks and suggestions. This massive amount of unstructured data produced, affects query processing performance adding to the difficulty in managing or retrieving the data. Many organizations are progressively exploring ways to comprehend and analyse this huge unstructured data to infer operational insights from it. We could solve many of the storage issues of unstructured data using the document-based NoSQL databases. But applying artificial intelligence to make exact matching predictions with the text data is remaining as a challenge. With the new method proposed here, the intelligent processing of the textual data stored in document-based NoSQL databases is made possible, and it is really an added benefit to those, who opt or use NoSQL databases for unstructured data storage.

The data surveying this study mines methods for extracting informative and interesting knowledge from learning student datasets. The amount of data stored in education big databases is growing at an alarming rate. As such, data processing and knowledge discovery techniques can be used to discover interesting relationships between different characteristics and assessments of students. Initially to propose a novel self-analysis model which performs analysis about the different big data learning services. From the result provided by the user, the service will be ranked and analyze about the knowledge from daily activity gathered by the learner. The proposed model performs analysis to provide efficient Educational Data Mining (EDM) E-Learning system based on machine learning to ranking the users and performance evaluation in their activities. The existing method does not consider the learner activities, ranking and it focus on single feature based classification so the system doesn’t provide a better classification result. These issues to overcome introduce an Extended Multi-Labeled Gradient Boosting (XMGB) improve the classification performance both of imbalanced dataset. The method initial stage apply the Adaptive Expectation-Maximization Mixture (AEMM) method cluster the data various group and extract the E-learning multiple feature set. In this method to compute the classification time and memory provide an efficient result. Then introduce an academic activity based weight score analysis model to evaluate the learner daily activates and exam score its help to the ranking and cluster the data groups. In this proposed method analysis result to evaluate the following performance matrix: Recall, precision, F measure, classification accuracy. In this simulation analysis of the proposed method XMGB are provide an efficient classification with less time complexity compared to other existing methods.

The primary objective of university education is to provide students with the required information and skills to enable them to make a successful contribution to the national development effort. In order to evaluate the level of expertise and skill of students, this preparation includes frequent examination and appraisal in the form of tests. Manual exams are carried out by most universities; Post Graduate and Under Graduate in India. Due to multiple uses made of the outcomes of the students, these examinations have high stakes. Consequently, the experiments became subject to different types of malpractice. Test malpractice affects the success of students in exams and leaves the scores/grades earned inaccurate, hence a challenge to examination bodies and the nation's education system (India). These are all disturbing signs that pose a danger to the nation. Examination malpractice has eaten deep into the Indian culture of education. Therefore, the object of this paper is to explore the problem of examination malpractice in India. The paper covered relevant measures, procedure setting/implementation and suggestions for this action. And finally, a model is proposed to stop malpractices in the examination. This IoT based model is used for detecting any metallic object or object in a range more than normal IR proximity sensor range. The block diagram of proposed model and circuit diagram for that model discussed in detail. This proposed model may be used for any investigation in the universities examinations.

Chatbots are becoming increasingly popular as virtual assistants, many businesses are launching If-This-Then-That programs to help them get started. Such systems, on the other hand, often generate chatbots that are stagnant and difficult to handle. The market for chatbots is increasing. Computer systems are often required, and online connections are improved by allowing users to express their needs, desires, or questions naturally and clearly by speaking, tapping, and talking. They're easy to use, perfect for people of all ages, and have the most detailed responses to questions. The majority of today's education is distributed through e-learning. A chatbot is one of the most powerful ways for students to read, as it can answer questions at any time without the need for human interaction. This chatbot is highly capable of overcoming student uncertainty without the need for human interaction. The IF THIS Then THAT paradigm is used by the bulk of chatbots. Natural language processing and deep learning technologies were used to build this chatbot. As a consequence, the chatbot will comprehend questions at a higher level.

Surface water bodies are getting contaminated day by day. Pollutants like 2-Chloropyridine (a class of halogenated pyridine derivative which are widely used in pharmaceutical and agrochemical sector) is detected in surface water bodies. It is toxic and carcinogenic. One of the reason of its presence in water bodies can be attributed to effluents from sewage treatment and industrial waste treatment plants, which may be due to inefficient conventional treatment technologies. Use of Advanced Oxidation technologies like Fenton’s oxidation has proven to be a promising alternative to degrade these recalcitrant and non-biodegradable compounds. The Present study accesses the applicability of laterite soil as a source of iron catalyst in Fenton’s oxidation process to degrade2-chloropyridine (2-CP) at various concentrations. Parameters like pH, dosage of laterite iron, hydrogen peroxide are optimized. Effect of initial concentration of the target compound on degradation kinetics is also investigated. Up to 75% degradation was achieved in a total reaction time period of 10hrs corresponding to Laterite iron: H2O2 ratio of 1:50 at a pH of 3 for a sample containing 2-CP compound at 10 mg/L. Use of iron in Fenton’s oxidation process harnessed from the laterite soil can be a suitable alternative to treat polluted water bodies contaminated with pharmaceutical halopyridine compounds.

Carbon Reinforced Plastics/polymers are metamaterials, widely used for diversified purposes for their unique features. The bibliometric analysis had been conducted to understand the active authors, organizations, journals, and countries involved in the research domain of “Carbon Reinforced Plastics”. All published articles related to “Carbon Reinforced Plastics” from “Scopus”, were analyzed using the VOS viewer to develop analysis tables and visualization maps. This article had set the objective to consolidate the scientific literature regarding the “Carbon Reinforced Plastics” and also to find out the trends related to the same. The most active journals in this research domain were Mechanics of Composite Materials, Journal of Materials Processing Technology, and Applied Mechanics Reviews. The most active countries were China, Japan, Portugal, and the United Kingdom. The leading organizations engaged in the research regarding Carbon Reinforced Plastics were the University of Tokyo of Japan, the Russian Academy of Sciences of Russia, and the Ministry of Education of China. The most active authors who had made valuable contributions related to Carbon Reinforced Plastics were Yates B. Davim J.P. Reis P. and Ishikawa T.