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Since 1896, acid stimulation technology has been widely using in world's reservoirs. Temporary plugging agent (TPA) was one of the key materials for achieving uniform acidification of long wellbore in heterogeneous reservoirs. To solve the problems of uncontrollable crosslinking time, incomplete degradation, and weak acid resistance of existing polymer TPA, this study developed a novel TPA named SAXG using environmental-friendly materials. The formula of SAXG was optimized, and its performances were tested through a series of SEM, FT-IR, temporary plugging, core displacement, etc. Some interesting insights have been gained. First, SAXG, a type of hydrogel, was formed through calcium ion cross-linking and intermolecular forces. The optimal formula of SAXG was 0.7 wt% sodium alginate + 0.3 wt% sodium gluconate through orthogonal experiments, with deformation and gelation time as the objectives. Secondly, the gelation time of SAXG was controllable, from 14 min to 456 min. SAXG can be completely degraded in the ground or reservoir, and factors such as temperature and acid only affect its degradation rate. Finally, the core permeability after temporary plugging acidification increased by 2.79 times compared to that after traditional acidification. The breakthrough pressure of SAXG was 9.1 MPa, and the permeability recovery rate after SAXG degradation was as high as 98.6%. [ABSTRACT FROM AUTHOR]

The combustion of traditional pyrotechnics will pose great risks to the environment and human health. Although sulfur‐free pyrotechnics prepared from metals or expired military gunpowder have been used to solve this problem, the high sensitivity of them has resulted in insufficient safety. Therefore, new eco‐friendly and safe pyrotechnics are urgently needed. In this study, we prepared novel metal‐free pyrotechnic compositions for fireworks based on 5‐amino tetrazole. The optimized formulations are proposed by calculation. Particle size effects on thermal stability and kinetics are tested. Then, the sensitivity tests, moisture absorption, and burst temperature test were analyzed and compared. The combustion heat and specific volume were also measured. The Py‐GCMS and PM2.5 were used to clarify the composition of gas products and confirm their environmental‐friendly performance. The findings revealed that the novel pyrotechnics has a small amount of combustion residue, greater safety performance, and less PM2.5 concentration. The novel pyrotechnics could generate 564.9 mL/g clean and non‐toxic gas composed of 93.2% N2, H2O, and CO2 without any NOx or SO2 vapor. The test results suggest that the new pyrotechnics can effectively increase gas production and reduce the content of CO and PM2.5. So, it has great potential in application. [ABSTRACT FROM AUTHOR]

Bimetallic nickel-molybdenum nitride (NiMoN) catalysts have attracted great attention due to their remarkable similarity to group VIII noble metals in terms of electronic structure, good electron conductivity, and durability for the hydrogen evolution reaction (HER). However, the existing approaches for fabricating NiMoN catalysts usually entail a series of multiple steps and hazardous ammoniated ingredient. As a result, these methods are difficult to be scaled up for large-area fabrication towards industrial water splitting. Herein, a hierarchical composite NiMoN@Ni(OH) 2 @NF composite electrode with a sheet morphology was synthesized based on a rational combination of seawater etching and magnetron sputtering. This method is easily scalable for producing large-area electrodes with minimal pollution. The incorporation of Ni(OH) 2 @NF nanoarray carriers enhances the exposure of additional active sites on the NiMoN layer, thereby augmenting the electrochemically active specific surface area of the electrode.The as-synthesized NiMoN@Ni(OH) 2 @NF electrode demonstrates excellent HER activity, with an overpotential of 57 mV at 10 mA cm−2, and exhibits remarkable long-term catalytic stability for over 100 h at a current density of 100 mA cm−2.This study presents an eco-friendly and straightforward method for preparing large-scale transition metal nitride catalysts with high catalytic activity. Large-area NiMoN@Ni(OH) 2 @NF composite electrodes were prepared using a combination of environmentally friendly and cost-effective seawater etching, along with reactive magnetron sputtering methods. [Display omitted] • The NiMoN@Ni(OH) 2 @NF composite electrodes were fabricated utilizing a simple and eco-friendly method. • NiMoN@Ni(OH) 2 @NF demonstrates excellent electrocatalytic activity and stability for HER. • The technology demonstrates excellent potential for large-scale fabrication. [ABSTRACT FROM AUTHOR]

Shahbaz Ahmad,1 Shujaat Ahmad,2 Shujat Ali,3 Muhammad Esa,2 Ajmal Khan,1 Hai Yan1 1School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, People’s Republic of China; 2Department of Pharmacy, Shaheed Benazir Bhutto University, Sheringal Dir Upper Khyber Pakhtunkhwa, Pakistan; 3College of Electrical and Electronic Engineering, Wenzhou University, Wenzhou, 325035, People’s Republic of ChinaCorrespondence: Hai Yan, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, People’s Republic of China, Email haiyan@ustb.edu.cn Shujaat Ahmad, Department of Pharmacy, Shaheed Benazir Bhutto University, Sheringal Dir Upper Khyber Pakhtunkhwa, Pakistan, Email shujaat@sbbu.edu.pkAbstract: Green synthesis of silver (Ag) and gold (Au) nanoparticles (NPs) has acquired huge popularity owing to their potential applications in various fields. A large number of research articles exist in the literature describing the green synthesis of Ag and Au NPs for biomedical applications. However, these findings are scattered, making it time-consuming for researchers to locate promising advancements in Ag and Au NPs synthesis and their unexplored biomedical applications. Unlike other review articles, this systematic study not only highlights recent advancements in the green synthesis of Ag and Au NPs but also explores their potential unexplored biomedical applications. The article discusses the various synthesis approaches for the green synthesis of Ag and Au NPs highlighting the emerging developments and novel strategies. Then, the article reviews the important biomedical applications of green synthesized Ag and Au NPs by critically evaluating the expected advantages. To expose future research direction in the field, the article describes the unexplored biomedical applications of the NPs. Finally, the articles discuss the challenges and limitations in the green synthesis of Ag and Au NPs and their biomedical applications. This article will serve as a valuable reference for researchers, working on green synthesis of Ag and Au NPs for biomedical applications. Keywords: green synthesis of nanoparticles, silver and gold nanoparticles, environmental-friendly, biomedical applications, unexplored potentials

Ammonia leaching has been gained considerable attention for its ability to selectively extract nickel and cobalt from spent ternary cathode material. Despite its efficacy, the subsequent recovery of ammonia leachate remains challenging. Herein, a short-process and sustainable method for the synthesis of nickel-cobalt oxide via ammonia evaporation of ammonia leachate and heat treatment of the resultant precursor has been proposed. The ammonia evaporation process, conducted at an evaporation temperature of 130 °C with hydrazine hydrate as a reducing agent, facilitated the precipitation of ∼95% Ni and ∼99% Co as a precursor. Subsequently, the effect of precursor roasting temperature on electrode material synthesis was systematically studied. The precursor was roasted at 300 °C to successfully synthesize nickel-cobalt oxide. Physical and electrochemical characterizations revealed that the nickel-cobalt oxide possesses a significant specific surface area of 161.150 m2/g, and exhibits excellent oxygen evolution reaction performance, evidenced by an overpotential of 350.7 mV at 10 mA/cm2 and a Tafel slope of 159.8 mV/dec. Overall, the proposed method not only promotes the recycling and utilization of ammonia reagents and mother liquor, but also introduces an innovative approach for the synthesis of nickel-cobalt oxide as an electrode material. [Display omitted] • A sustainable process for recovering Ni and Co from ammonia leachate was proposed. • More than 95% of Ni and 99% of Co were precipitated by ammonia evaporation. • Nickel-cobalt oxide as electrode material was synthesized at 300 °C for 3.0 h. • The synthesized nickel-cobalt oxide exhibits excellent electrochemical properties. [ABSTRACT FROM AUTHOR]

Post-consumer soft plastics often face inadequate management practices, posing threats to both human life and the environment while also leading to the loss of valuable recyclable materials when not recycled. Traditional mechanical recycling methods are unsuitable for waste soft plastics due to their thin and flimsy nature. This study presents an effective, user-friendly process for converting waste soft plastics into new products, generating value, and expediting their collection and recycling without the need for pelletization. The outcome of this process was compared with products derived from traditional recycling and commercially available alternatives through various analytical techniques including tensile testing, Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffractometry, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The findings suggest that waste soft plastics can be transformed into flexible sheets without significant alterations to their properties. In particular, the ultimate tensile strength of samples recycled using the developed process in this study and traditional recycling were found to be 25.9 ± 0.4 and 25.2 ± 0.8 MPa, respectively, surpassing commercially available products by nearly 15 MPa. Additionally, a life cycle assessment revealed that producing flexible sheets from waste soft plastics using this innovative approach, rather than virgin polymer, could reduce fossil fuel depletion and global warming by 99.4% and 94.6%, respectively. This signifies the potential of the process to mitigate environmental pollution and produce high-quality products exclusively from 100% waste plastics. [ABSTRACT FROM AUTHOR]

Cyanide-based baths are generally used industrially to produce silver and gold coatings via electroplating. Baths containing ([Au(CN)2]−) and ([Ag(CN)2]−) are used for the deposition of gold and silver coatings, respectively. However, due to the severe toxicity, the technical personnel involved in work are at risk. Additionally, the disposal of cyanide-containing wastes poses a significant threat to the environment as they pollute various natural resources. The coatings produced from alkaline cyanide-based baths cause embrittlement of electronic circuit patterns. Due to these reasons, many cyanide-free baths have started to replace the existing cyanide-based baths. In the cyanide-free baths, the primary cyanide complexing agent is replaced with eco-friendly alternative compounds like sulphite, thiosulphate, thiourea, DMH, EDTA, and ionic liquids (ILs). This review article provides an overview of the various cyanide-free electroplating baths available for electroplating silver and gold that are either used for commercial practice or are developed for laboratory-scale use. [ABSTRACT FROM AUTHOR]

Aluminum dross produced from the smelting process of aluminum is a toxic solid waste that easily hydrolyzes and releases poisonous gases in contact with water, which contains large numbers of fine oxidized aluminum droplets. In this study, an environmental-friendly method for efficient recovery of aluminum droplets from aluminum dross was proposed through mechanical activation and super-gravity separation. Firstly, the aluminum dross with different particle sizes of 8.0–50.0 mm, 4.0–8.0 mm, and < 4.0 mm was mechanically activated, and the oxidized films of metallic aluminum droplets were greatly destructed via milling. However, the driving force of gravity was not sufficient to drive the molten aluminum droplets to detach from the oxidized films at high temperatures. With the enhancement of the super-gravity field, almost all of the aluminum droplets efficiently escaped from the oxidized films and fully recovered from the aluminum dross within 5 min with a high recovery ratio of 97.14% and a high purity of 99.17 wt%. Compared to the conventional process of separating aluminum, this study provides an environmental-friendly method to efficiently recover aluminum droplets from aluminum dross without the problems of secondary aluminum dross production, dust pollution, and gas pollution. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrophobically-modified cellulose derivatives have been considered for improved oil recovery applications. However, the subsurface reservoir environment defined by combinations of brine salinity, temperature, and porous media-induced shear can pose an adverse challenge to the mobility control prospects of these materials. Previous studies have focused mostly on amphiphilic cellulose ethers. This study is based on a cellulose ester, herein, a novel polymeric surfactant derived from sodium cellulose sulfate is investigated. Rheological studies were carried out on the novel material under variable external reservoir conditions. From the results, the amphiphilic polymer was able to initiate associative behavior at a low concentration of 0.15 g/L. The biopolymeric surfactant exhibited tolerance to temperature and shear over the tested range of 35 °C to 75 °C, and 100 RPM to 250 RPM respectively by retaining its original rheological profile. The viscosity improved over a brine salinity range of 10,000ppm to 60,000ppm as it increased from 45.75 cp to 49.1 cp. From these findings, it can be inferred that the novel cellulose derivative is a good mobility control agent, and should be considered for oilfield applications that target cheap, cost-effective, and environmental-friendly operations. [ABSTRACT FROM AUTHOR]

Recently, the global warming and climate changes have aroused focus of attentions. Hence, there is an increased demand to capture, utilize, and sequestrate the greenhouse gas, i.e., carbon dioxide (CO2), for promising applications. Functionally cooperating mini‐generators are a kind of self‐propelled smart devices that can harvest environmental energy and convert it to electricity through Faraday's law. But traditional mini‐generators are based on an energy‐consuming process appealing for energy consumption from high‐grade state to low‐grade one. Herein, a mini‐generator based on photosynthesis with CO2 as the fuel is designed. The generator can convert the internal energy of O2 bubbles produced by photosynthesis to electricity. This is an energy conversion from the lowest energy state to the applicable energy. Based on the high‐efficiency photosynthesis of hydrophyte, spontaneously water‐dissolved CO2 can afford to induce regularly cycled surfacing‐diving motion, and the induced electrical output can simultaneously actuate multiple electronic components. Owing to the weather sensitivity of the photosynthesis, the system can be used to monitor weather through reading the changes of output electrical signals. By integrating the artificial smart device with natural plants, this research will promote the applications of miniaturized devices toward green development. [ABSTRACT FROM AUTHOR]

Abstract This study examines the relationship between pro-environmental attitudes, e-bike adoption motivations, and tourist green behavior (TGB). Environmental psychologists have increasingly focused on understanding “green” tourist behavior determinants. The TGB distinguishes tourists from pro-environmentalists for relatively everyday simple actions, and e-bike adoption motivations can serve as a mediator to better understand pro-environmental attitudes– tourist green behavior relationships. We tried to bridge this gap by conceptualizing TGB and investigating the mediating role of e-bike adoption motivations in the relationship between pro-environmental attitudes and TGB. Derived from an online survey-based sample of 682 e-bike users, the data were investigated using structural equation modeling analysis. Findings showed that directly and indirectly, pro-environmental attitudes significantly influenced TGB, and e-bike adoption motivations (e.g., cost-effective motivation, intrinsic motivation, technology motivation) mediate their concerned paths. Therefore, the stakeholders and marketing practitioners should emphasize the importance of pro-environmental attitudes and e-bike motivations within the TGB and e-bike adoption campaigns. [ABSTRACT FROM AUTHOR]

Oil and gas resources are one of the key energy sources in the world. The safety, environmental protection and production efficiency of oil and gas transportation are crucial. In view of the problems existing in the current oil and gas mixed transportation technology, the displacement model of oil and gas mixed transportation is established for the oil and gas mixed transportation process in this study. Through the upgrading of system program and the optimization of equipment, the flow law of oil and gas mixed transportation in the mixed transportation pipeline is studied. On this basis, the effects of different inclination angles on gas holdup, pipeline pressure drop and fluid migration velocity are analyzed. Then the application effect of the optimized process is analyzed. The results show that with the increase of the inclination between the pipeline and the ground, the gas volume at the top of the pipeline expands several times more than that at the bottom of the pipeline, resulting in a sharp increase in the gas holdup at the top of the pipeline and an increase in the fluid velocity. Meanwhile, with the increase of mixed transportation capacity, the pressure drop of the pipeline shows a decreasing trend as a whole. With the optimized integrated environmental monitoring system, the gas holdup during oil and gas transmission can reach 77.48%, the gas phase velocity can reach 6.98 m/s, and the pressure drop is 6.80 MPa under the process parameters of 90° mixed transmission pipeline inclination and 3000 m3/h mixed transmission capacity. This research is helpful to improve the environmental protection and efficiency of oil and gas mixed transportation technology, and has good economic prospects. [ABSTRACT FROM AUTHOR]

Preparation of nano-rod aluminosilicate Mazzit (MAZ) zeolite under low-cost and environmental-friendly route is attractive, but still challenging. Herein, we report a green route for synthesizing nano-rod MAZ zeolite (MAZ-N) using low-cost and environmental-friendly choline chloride as template. Various characterizations including powder X-ray diffraction (XRD), scanning electron microscope (SEM), N2 sorption, and thermogravimetry-differential thermal analysis (TG-DTA) show that MAZ-N samples have good crystallinity and uniform porous structures. Furthermore, the crystallization process and impact of synthesis conditions of MAZ-N samples have been investigated in detail. These results suggest the potential applications of MAZ-N zeolites as supporting catalyst compounds in industrial processes. [ABSTRACT FROM AUTHOR]

Wearable sensors for sweat biomarkers can provide facile analyte capability and monitoring for several diseases. In this work, a green wearable sensor for sweat absorption and chloride sensing is presented. In order to produce a sustainable device, polylactic acid (PLA) was used for both the substrate and the sweat absorption pad fabrication. The sensor material for chloride detection consisted of silver-based reference, working, and counter electrodes obtained from upcycled compact discs. The PLA substrates were prepared by thermal bonding of PLA sheets obtained via a flat die extruder, prototyped in single functional layers via CO2 laser cutting, and bonded via hot-press. The effect of cold plasma treatment on the transparency and bonding strength of PLA sheets was investigated. The PLA membrane, to act as a sweat absorption pad, was directly deposited onto the membrane holder layer by means of an electrolyte-assisted electrospinning technique. The membrane adhesion capacity was investigated by indentation tests in both dry and wet modes. The integrated device made of PLA and silver-based electrodes was used to quantify chloride ions. The calibration tests revealed that the proposed sensor platform could quantify chloride ions in a sensitive and reproducible way. The chloride ions were also quantified in a real sweat sample collected from a healthy volunteer. Therefore, we demonstrated the feasibility of a green and integrated sweat sensor that can be applied directly on human skin to quantify chloride ions. [ABSTRACT FROM AUTHOR]

In order to improve the high temperature stability, salt resistance performance and reduce the environmental pollution of the filtration reducer, a new organic/inorganic composite micro-nano environmental-friendly filtration reducer (EFR-1) was synthesized by grafting sodium vinyl sulfonate (SVS), N-vinylpyrrolidone (NVP), acrylamide (AM) and 2-acrylamide-2-methylpropanesulfonic acid (AMPS) onto the surface of nano calcium carbonate through inverse emulsion polymerization. Furthermore, the physical and chemical characteristics of EFR-1 were characterized by fourier transforms infrared spectroscopy, transmission electron microscopy, and particle size distribution tests. The new-synthesized EFR-1 is characterized by core-shell structure and high sphericity with D50 as well as Zeta potential absolute value above 40mV, which leads to good dispersion. EFR-1 also exhibited excellent filtration reduction performance in saturated salt water and high temperature resistance up to 200°C and API filtration volume of 11.2 mL. Besides, biological toxicity (EC50) of 96500 mg/L and biodegradability (BOD5/CODCr) of 18.56% proved an excellent environmental-friendly performance. The mechanism was clarified that the micro-nano particles easily absorb on the surface of the clay particles through hydrogen bonding, resulting in the colloidal stability of bentonite slurry under high temperature and high salt concentration, which is in favor of forming a thin and dense filter cake to effectively reduce the filtration volume of drilling fluids. [ABSTRACT FROM AUTHOR]

The utilization of polyvinyl chloride (PVC) coatings is pervasive across numerous industries and market applications. However, due to its highly flammable nature, PVC coatings generate a large amount of toxic smoke when burning. We developed a bio-derived flame retardant and smoke suppressant, PASn@BiOCl, utilizing interface assembly technology. Compared to pure PVC coating, the addition of only 15 phr BiOCl@PASn significantly enhanced its various properties. The limiting oxygen index of PVC coating improved from 23.4% to 29.2%. Additionally, the UL-94 vertical burning test rating of the PVC coating has been improved from NR (No Rating) to V-0. More importantly, the peak heat release rate and peak smoke production rate of the PVC coating decreased by 70.7% and 60.7%, respectively, demonstrating the effective suppression of combustion and smoke generation. We also analyzed the pyrolysis products at different temperatures and the combustion behavior at various stages using Py-GC/MS and TG-IR techniques. It was observed that the char layer generated by PVC/BiOCl@PASn exhibited greater stability and density. The decomposition products including bismuth oxides, tin oxides, and phosphorus oxides formed a stable insulating layer on the charcoal surface, which effectively acted as a cohesive phase flame retardant. This highly efficient flame retardant and smoke suppressant PVC coating has enormous application potential in the fields of building materials, automobiles, textiles, and electrics. [Display omitted] • A novel bio-based BiOCl@PASn was successfully designed and synthesized. • The flame retardant and smoke suppression properties of PVC coatings were significantly improved. • The mechanism of action of PVC/BiOCl@PASn was analyzed and summarized. • The research has broad applications in building materials, the automotive industry, and other fields. [ABSTRACT FROM AUTHOR]

• An environmental-friendly wellbore stabilizer was developed by modifying gelatin with polyvinyl alcohol and methacrylic acid. • Besides electrostatic interaction, the stabilizer forms films on Na-BT at high temperature, enhancing stability. • This environmental-friendly wellbore stabilizer has high temperature resistance and can withstand temperature up to 200 °C. In the development of deep shale oil and gas, the working temperature of the water-based drilling fluids is relatively high, which can cause wellbore instability due to the poor temperature resistance of the traditional environmental-friendly additives. To address this issue, this study presents a wellbore stabilizer called PMG, prepared by modifying gelatin (GT) with a resin synthesized by polyvinyl alcohol (PVA) and methacrylic acid (MA) through hydrothermal free radical polymerization, and it can withstand temperature up to 200 °C. The synthesis and thermal stability of PMG were confirmed by Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The wellbore stability performance of PMG was evaluated by linear swelling test, rolling recovery test, core immersion experiment and point load test and the wellbore stability mechanism was also investigated. The results reveal that the swelling height of sodium-based bentonite (Na-BT) in 2.0 % PMG solution at 150 °C is only 0.97 mm; the hot-rolling recovery rate in 2.0 % PMG solution at 200 °C is 72 %; the artificial core still maintains its original appearance after being immersed in 2.0 % PMG solution at 200 °C for 16 h, and the compressive strength increases by 12 %, effectively strengthening the wellbore. In addition, the EC 50 value of PMG is > 106 mg/L, and the BOD 5 /COD cr value is 31 %, indicating that it is non-toxic and biodegradable. PMG has excellent wellbore stability performance, in addition to being able to adsorb on the surface of Na-BT by electrostatic action and hydrogen bonding, the PMG micelles that precipitated from the aqueous solution due to the breaking of hydrogen bonds in the molecular chain at high temperature also form a film on the clay surface, aggregating and cementing the clay particles together, further enhancing the wellbore stability. [ABSTRACT FROM AUTHOR]

C4F7N/CO2 mixture has been widely studied as an environmental-friendly insulating gas expected to replace sulfur hexafluoride (SF6) in high-voltage equipment. In high-voltage power systems, the medium dielectric characteristics under switching impulse (SI) voltage are an important factor in insulation coordination. Nevertheless, few studies on this aspect of C4F7N/CO2 mixture have been reported. This article investigates the surface flashover of a cylindrical insulator in a C4F7N/CO2 mixture under switching voltage. The effects of molar fraction, gas pressure, creepage distance, and insulator materials on surface flashover voltage are studied in a uniform field. The result shows that the increase of flashover voltage indicates a saturation trend with the increase of C4F7N molar fraction and pressure, respectively. The dielectric strength of 13% C4F7N/87% CO2 relative to SF6 can reach at least 84%. The limiting factors of the flashover voltage increase under high pressure are preliminarily discussed. Additionally, the empirical formula on the critical flashover electrical field has been obtained, which can provide a reference for insulation design for environment-friendly gas insulation equipment. [ABSTRACT FROM AUTHOR]

In recent years, there has been much interest in developing advanced and innovative approaches for sensing applications in various fields, including agriculture and environmental remediation. The development of novel sensors for detecting heavy metals using nanomaterials has emerged as a rapidly developing research area due to its high availability and sustainability. This review emphasized the naturally derived and engineered nanomaterials that have the potential to be applied as sensing reagents to interact with metal ions or as reducing and stabilizing agents to synthesize metallic nanoparticles for the detection of heavy metal ions. This review also focused on the recent advancement of nanotechnology-based detection methods using naturally derived and engineered materials, with a summary of their sensitivity and selectivity towards heavy metals. This review paper covers the pros and cons of sensing applications with recent research published from 2015 to 2022. [ABSTRACT FROM AUTHOR]

Plastic has transformed the world; however, it generates a huge amount of waste plastics. It is well evident that, if urgent action is not undertaken on plastic pollution, it will pose threats to not only the environment, but also human life. Just simply discarding waste plastics will result in wasting a lot of valuable materials that could be recycled. Recently, the use of waste plastics has been considered for producing wood plastic composites (WPCs), which are superior to normal wood. Waste plastics are pelletized using an extruder and are then subjected to injection molding. In this study, investigations were carried out to determine the possibility of producing WPCs without the palletization of waste plastic to turn WPC production into a shorter, simple, and easy-to-achieve process. Here, a waste milk bottle, a familiar single-use plastic, was picked as a case study. Waste plastic granules and wood particles were mixed and directly injection molded to produce valuable WPCs. The water absorption of WPCs with 20% wood is 0.35%, and this increased to 0.37% when wood content was increased to 40%. The tensile strength at yield, elongation at break, and impact strength of WPCs with 20% wood content are 19.54 MPa, 5.21%, and 33.92 KJ/m2, respectively, whereas it was 17.23 MPa, 4.05%, and 26.61 KJ/m2 for the WPCs with 40% wood content. This process can be a potential solution for two problematic wastes at the same time. [ABSTRACT FROM AUTHOR]

In this experimental study on self-compacting concrete (SCC), the Manufactured sand (M-sand) and Fly ash (FA) were utilised for partial replacement of Natural sand (N-sand) and Ordinary Portland Cement (OPC), respectively. N-sand was partially replaced by M-sand at various percentage levels, after the dose of FA in the mix was optimised. In terms of compressive strength, the optimum replacement level of OPC by FA was 20%, whilst for replacement of N-sand by M-sand it was 50%. Two types of mixes were prepared to compare the macro and micro level properties of SCC, i.e., SCC-I (100%OPC + 100%N-sand) and SCC-II (80%OPC + 20%FA + 50%N-sand + 50%M-sand). The characteristics of fresh concrete mixes were determined using Slump flow, T50 time, V-funnel, L-box, U-box, and J-ring tests. After 28 days of curing in tap water, both types of specimens were exposed to a solution of ammonium sulphate [(NH4)2SO4] containing sulphate salt concentration of 2.0 g/l for 360 days to test their durability. Loss in compressive strength, weight change, sorptivity, and micro-structural changes (XRD, SEM, and EDS) all were evaluated for up to 360 days. It was found that the use of FA and M-sand in concrete makes it more environmental-friendly and durable, as well as have better performance in a sulphate environment. [ABSTRACT FROM AUTHOR]

To improve multiple heterointerface coupling efficiencies and efficiently engineer the pore structure of porous carbon, a kind of magnetic cobalt nanoparticles embedded porous carbon framework, derived from economical biomass, was designed in the present study. The resulting magnetic embedded porous carbon framework showed exceptional dielectric responses and a significant polarization effect because of the higher contact surface utilization than the ordinary loaded structure. The effective absorbing bandwidth covers 6.6 GHz with a thickness of 2.3 mm, indicating its capacity to address the increasingly problematic electromagnetic (EM) pollution issue. Meanwhile, the magnetic embedded structure with the carbon framework could protect the embedded particles from common corrosion issues, even after a long time environmental adaptability assessment in the lab and faintly acid condition. This work highlights a potential strategy for the design and synthesis of high-performance carbonaceous EM absorbers. [Display omitted] [ABSTRACT FROM AUTHOR]

The aim of this research is to determine the effectiveness of a mixture of neem (Azadirachta indica A. Juss.) and tobacco (Nicotiana tabacum L.) as bioinsecticides on the mortality of aphids (Toxoptera citricidus [Kirkaldy, 1907]) and the green scale (Coccus viridis [Green, 1889]). Data were analyze by variance and by Duncan Multiple Range Test (DMRT) at 5 % level of significance. The results showed that the bioinsecticide caused mortality of T. citricidus more than 50 % starting from 24 h after application (HAP) and at the 168 HAP the mortality 96 % to 100 %, not significantly different from the imidacloprid synthetic insecticide and significantly different from the control. The application of the bioinsecticide was less effective against C. viridis. The mortality of C. viridis is significantly different from the insecticide imidacloprid. The application of a bioinsecticide mixture of neem and tobacco extracts was effective against the brown citrus aphid T. citricidus, but less effective against the green scale C. viridis.

The application of conventional aqueous film-forming foam (AFFF) has been restricted due to the environmental hazards caused by long-chain fluorocarbon surfactants. Environmentally friendly firefighting foams are urgently needed. In this study, AFFFs based on a long-chain fluorocarbon surfactant and a short-chain fluorocarbon surfactant, and fluorine-free foams based on a silicone surfactant and a mixture of foam stabilizers are prepared. The critical properties, including film-forming ability, foam stability, and foam spreading property, of foams and a commercial AFFF are investigated systematically. The fire extinguishing and burn-back performances are evaluated by a small-scale test method. Results indicate that the removal of fluorocarbon surfactants from AFFF leads to an apparent decrease in film-forming ability, foam stability, foam spreading property, and corresponding fire extinguishing performance. AFFF based on short-chain fluorocarbon surfactant shows excellent extinguishing and burn-back performances even if its film-forming ability, foam stability, and foam spreading are slightly worse than those of conventional AFFF. Although FfreeF cannot form an aqueous film and exhibits poor foam spreading, it demonstrates satisfactory fire extinguishing performance and optimal burn-back performance depending on its superhigh stability. This study can provide guidance in the development of environmentally friendly firefighting foams. [ABSTRACT FROM AUTHOR]

The environmental–friendly synthesis of nanostructural aluminium nitride with high purity and good dispersity properites is regarded as a technical issue. In this paper, an arc discharge with assistance of direct nitridation has been put forward to synthesize aluminium nitride nanoparticles that simultaneously possess the high purity of more than 97%, the average particle size of 99.1 nm, and the specific surface area of 60.8 m2 g−1. Compared with the aluminium nitride prepared by direct nitridation of aluminium nanoparticles, the unique framework of the satellite structural and small-sized aluminium nanoparticles attached on larger-sized aluminium nitride nanoparticles is prepared by arc discharge, which can prevent effectively agglomeration and coalescence of aluminium nitride nanoparticles in the next nitridation process. In addition, the direct nitridation process requires a low temperature of 600 °C for 2 h, because the nonstructural aluminum particles are evenly distributed on the surface of aluminum nitride and process the low average diameter of 40 nm. The work provides an efficient technique to open up the possibility of technological advancement for preparing metal nitride nanoparticles with high purity and good dispersity. [ABSTRACT FROM AUTHOR]

An environmental friendly superabsorbent composite (SAC) based on rice, (Oriza sativa L.), husk was created by the scientific group at Faculty of Science, Tanta University, and City of Scientific Research and Technological Applications (SRTA-City), Egypt. SAC was tested for its ability to improve soil water retention, control the release of urea, and its biodegradability in soil. The effect of SAC on sweet pepper, Capsicum annuum, productivity under severe deficit irrigation conditions was studied. Doses of irrigation water representing percentage ∼16.7, 11.9, 7.1, and 2.4 of the actual crop water requirements (CWR) were tested in soil treated with 0.25, 0.50, 0.75, and 1.00 wt% SAC. The tested SAC lost ∼60% of its weight in 150 days. Soil water retention and urea release rates were improved plant growth in response to the addition of SAC. Application of ∼11.9% of CWR with 1.00 wt% SAC resulted in significantly better crop production than other treatments without SAC. This could annually save about 154.44 million cubic meters (MCM) to be directed for horizontal expansion and improve food security. [ABSTRACT FROM AUTHOR]

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A hyperbranched polyester with carboxyl end group (HPC) was synthesized by using trimellitic anhydride and neopentyl glycol as raw materials via A2 + B3 polycondensation. Then, waterborne hyperbranched polyester acrylate (WHPC) was synthesized by partially modifying the carboxylic groups of HPC with glycidyl methacrylate. In order to explore the influence of molecular weight, acrylate groups content, and ion groups content on performances, a series of WHPC films with different molecular weight, acrylate groups content, and ion groups content were prepared. The dynamic light scattering spectrometer analysis shows that the higher ionic groups content and the lower molecular weight cause the smaller particle size. The ionic group content has a positive effect on the solubility. The smaller molecular weight and particle size cause the lower viscosity. The Fourier-transform IR spectrophotometer reveals that the double bond final conversion increased with increasing acrylate groups content. The final conversion is between 69 and 86%. The curing speed is fast, and the curing time is about 70 s due to the numerous end groups owned by the hyperbranched structure. The dynamic mechanical thermal analysis coupled with end-use mechanical property tests illustrates that the crosslink density has a positive effect on the storage modulus and a negative effect on the flexibility. It is also found that glass transition temperature and pencil hardness are determined by the balance between crosslink segment and hyperbranched polyester segment. The thermogravimetric analysis proves that increased crosslink density and molecular weight promote the heat resistance of films. This work utilizes a novel hyperbranched structure that excels in viscosity, flexibility, and water solubility. Furthermore, the preparation process is convenient. [ABSTRACT FROM AUTHOR]

Environmental-friendly and highly efficient combustion suppression performance is the requirement for extinguishant. Dry water extinguishant integrates the advantages and characteristics of both dry powder and water mist extinguishant, so it has better fire extinguishing efficiency. Moreover, dry water extinguishant has less residue, no fugitive settling, non-toxic and harmless advantages after fire extinguishing. This work focus on producing dry water extinguishant powder by high-speed shearing. Then, the influence of the proportion of each component in the extinguishant formula on the coating effect was analyzed. The extinguishing effect of the optimized four dry extinguishing agents was tested by a portable spray device. Experiment results show that optimized four extinguishing agents are effective in extinguishing n-heptane fire and anhydrous ethanol fire. Among them, ammonium dihydrogen phosphate dry water extinguishant has the highest extinguishing efficiency to n-heptane fire, and potassium oxalate dry water extinguishant has the highest extinguishing efficiency to anhydrous ethanol fire. [ABSTRACT FROM AUTHOR]

The application of conventional aqueous film-forming foam (AFFF) has been severely restricted due to the serious environmental hazard caused by the key component, fluorocarbon surfactants. Environmental-friendly fluorine-free firefighting foams need to be developed urgently. In this study, five silicone surfactants are chosen as key component to prepare fluorine-free firefighting foams. The aqueous solution properties of the fluorine-free firefighting foams are studied in details, including surface tension, interfacial tension, spreading property, viscosity and foaming ability. Foam drainage and foam spread on heptane surface are analyzed. Fire extinguishing and burn-back performance of fluorine-free foams is evaluated based on a small-scale standard method. Particularly, fire extinguishing and burn-back performance of a commercial AFFF is also evaluated as a comparison. Results show that fluorine-free foams cannot form aqueous film on cyclohexane surface, no matter whether spreading coefficient is greater than zero or not. Fluorine-free foams exhibit much better foam stability but worse foam spread property than commercial AFFF. Not all the fluorine-free foams containing silicone surfactant performed as well as AFFF containing fluorocarbon surfactant. Only fluorine-free foam containing silicone surfactant of OFX-5211 shows better fire extinguishing and burn-back performance than AFFF. The higher efficiency of fluorine-free foam in fire extinguishing and burn-back should be attributed to the stronger foam stability. [ABSTRACT FROM AUTHOR]

This research demonstrates the effectiveness of environmental-friendly modified cellulose to replace synthetic polymer as the rheology modifier in enhancing the environmental-friendly performance of clay-free water-based drilling fluids. This paper first introduces the long-chain hydrophobic groups into hydroxyethyl cellulose (HEC) molecules to synthesize the hydrophobic ally modified hydroxyethyl cellulose (HMHEC). The evaluation results indicate that after the HMHEC concentration exceeds its critical associating concentration (CAC), H:tvIHEC exhibits excellent viscosity, salt and shear resistance due to hydrophobic modification. Compared with the synthetic polymer PAM, HMHEC presents better environmental-friendly performance, with the ECso value being 60000mg/L and the BOD5/CODer ratio being 18.21 %. Furthermore, this paper performs rheological and filtration measurements to investigate the feasibility or compatibility of HMHEC as the rheology modifier for clay-free water-based drilling fluids. The results demonstrate that HMHEC has better rheological behavior, higher temperature stability and greater salt resistance than PAM and XC, and that it can be an environmental-friendly alternative to conventional rheology modifier in clay-free water-based drilling fluids. [ABSTRACT FROM AUTHOR]

In this investigation, we have prepared an environmental‐friendly waterborne coil coating primer. Waterborne saturated polyester resin and waterborne epoxy ester resin were selected as the binder resins, and methylated melamine resin and waterborne blocked isocyanate were selected as crosslinking resins. ZnMoO4, Zn3(PO4)2, Zn3Al(PO4)3, and AlH2P3O10 were selected as the anti‐corrosion pigments, and modified nano‐TiO2 particles and other fillers were also employed to further enhance the primer performance. It was found that when polyester/epoxy ester equals to 7/3; binder resins/curing agent equals to 5/1; pigments/binder resin is in range of 1.4–1.6; additives of each is in amount of 0.5 wt.%–1.5 wt.%, the obtained primer has ideal properties, such as T‐bend performance and qualified adhesion, and the salt spray resistance test can reach 360 h with the primer film thickness in range of 6 μm–7 μm after baking at 224 °C for 45 s. As to the coil coating primer film formation mechanism, Fourier transform infrared spectrum analysis indicates that both the amino resin and blocked isocyanate may react with the binder resin, and such chemical reactions can make them crosslinked to form a stereo‐network film, giving birth to a good overall performance of the obtained primer. [ABSTRACT FROM AUTHOR]

Featured Application: Thin-film materials with degradability and recyclability for the fabrication of degradable, dissolvable, resorbable, and/or compatible electronic devices, especially transient resistive switching devices for security information storage and neuromorphic computing as well as environmental-friendly applications. The environmental pollution generated by electronic waste (e-waste), waste-gas, and wastewater restricts the sustainable development of society. Environmental-friendly electronics made of degradable, resorbable, and compatible thin-film materials were utilized and explored, which was beneficial for e-waste dissolution and sustainable development. In this paper, we present a literature review about the development of various degradable and disposable thin-films for electronic applications. The corresponding preparation methods were simply reviewed and one of the most exciting and promising methods was discussed: Printing electronics technology. After a short introduction, detailed applications in the environment sensors and eco-friendly devices based on these degradable and compatible thin-films were mainly reviewed, finalizing with the main conclusions and promising perspectives. Furthermore, the future on these upcoming environmental-friendly electronic devices are proposed and prospected, especially on resistive switching devices, showing great potential applications in artificial intelligence (AI) and the Internet of Thing (IoT). These resistive switching devices combine the functions of storage and computations, which can complement the off-shelf computing based on the von Neumann architecture and advance the development of the AI. [ABSTRACT FROM AUTHOR]

In this paper, the environmental-friendly compound modified starch was introduced as the filtrate reducer in water-based drilling fluids. Firstly, a kind of compound modified starch (GCMS) was synthesized through both etherification modification and crosslinking modification. Then from the aspect of improve colloidal stability and filter cake quality of water-based drilling fluids, the filtration reduction mechanism of compound modified starch (GCMS) in water-based drilling fluids was detailedly investigated using infrared scanning dynamic stability analysis, CT scan characterization, particle size distribution analysis and permeability and compression coefficient measurement of filter cakes. It was concluded that complex network structure of GCMS formed by moderate cross-linking could significantly improve its high temperature stability, and enhancing the colloidal stability to improve particle size gradation of clay particles and the compressibility of filtrate cake is one of the filtrate reduction mechanisms of GCMS. This research demonstrates its feasibility or compatibility of compound modified starch (GCMS) as a filtrate reducer in water-based drilling fluids. [ABSTRACT FROM AUTHOR]

A type of multifunctional periodic mesoporous organosilica supported dual imidazolium ionic liquids PMO-IL-anion have been designed and prepared, characterized and evaluated as heterogeneous catalysts for the Knoevenagel condensation. The as-fabricated supported ionic liquids show good catalytic performances in the Knoevenagel condensation at room temperature, especially the supported ionic liquids PMO-IL-NTf 2 and PMO-IL-PF 6 , based on a synergetic effect between the Lewis-base-type sites of dual functionalized imidazolium ionic liquids and active sites of periodic mesoporous organosilica. The best catalytic performance over PMO-IL-NTf 2 was observed with excellent yields of 93∼99% in a short time of 20∼30 min. In addition, the heterogeneous catalyst offers simple operation for recovery and the recycling test showed that it could be reused for five times without significant loss of catalytic activity, thus making this process economical and environmental-friendly. [ABSTRACT FROM AUTHOR]

• The environmental-friendly and safe unpacking powder without sulfur, magnesium and aluminum was proposed firstly. • The new unpacking powder releases lower PM2.5 and PM10 and is more environmental-friendly during the actual firing process. • The new unpacking powder is safer, and more stable in the process of preparation, transportation and storage. • The new unpacking powder has a good discharge performance. • The new unpacking powder has the potential to replace the ordinary unpacking powder and apply to export in the fireworks. A novel environmental-friendly unpacking powder for fireworks which has no sulfur, no magnesium, no aluminum or their alloys has been prepared in this study: potassium perchlorate (75%), potassium hydrogen terephthalate (13%), micronano porous silicon (9%), carbon (2%), ferrocene (1%). The PM2.5 and PM10 were collected by the ambient air particulate sampler, and the gas product was tested with a smoke analyzer and gas chromatograph to investigate its environmental-friendly performance. The detonation radius was measured by similar triangulation method, and p–t curves were measured in a closed bomb to investigate its practicality. The heat of combustion, sensitivity and hygroscopicity of the formula were measured according to China fireworks industry standard to verify the safety of the novel unpacking powder. The test results suggest that new unpacking powder using micronano porous silicon can effectively reduce the PM content and the product does not contain SO 2 , so it can be applied to export. [ABSTRACT FROM AUTHOR]

Basalt fiber (BF) is an environmentally friendly material which can reduce environmental problem. In this study, CF/BF composite materials that can reduce the volume of carbon fiber (CF) by hybridizing BF and CF were studied. BF was specially laminated on the surface of CF so that the CF does not come into contact with the external environment. Basalt fibers were designed based on the arrangement angles and volume fraction. Evaluation by tensile, bending and intermittent shear tests, showed that the volume fraction of BF was more influential than the arrangement angles. When the volume fraction of BF was approximately 27%, high mechanical properties were obtained at all arrangement angles used in this experiment. [ABSTRACT FROM AUTHOR]