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• A simple, large-scale fabrication of cooling paper via pulping and papermaking technology. • The cooling paper is facilely deconstructed and regenerated to architect the secondary cooler. • The cooling paper features a high solar reflectance of 94% and emissivity of 0.95. • The cooling paper shows the sub-ambient temperature drop of 6 ∼ 8.8 °C under directly solar radiation at daytime. Passive radiative cooling materials provide coldness without energy consumption for all-day thermal comfort by reflecting solar irradiation and emitting heat into the 3 K universe. However, the conventional radiative cooling materials involve complex multilayer structures and unsustainable polymers, showing the non-recyclable disadvantage, which induces resource waste and environmental issues. Herein, we reported a low-cost, scalable, and eco-friendly radiative cooling material (namely cooling paper), consisting of the delignified, fibrillated cellulose fibers and nano-sized hydroxyapatite (HA) via the mature pulping and papermaking process. The resulting cooled paper can be recycled, and it can be easily deconstructed to harvest cellulose fibers and HA, individually. The recovered source materials can be reused to prepare secondary products that show comparable performance to the original cooling paper, including a high solar reflectance of ∼94% and an infrared emissivity of ∼0.95 in the atmospheric transparency window. Such cooling paper enables superior cooling performance with the temperature drop of 6 ∼ 8.8 °C under directly solar radiation. Based on the EnergyPlus simulation, our cooling paper shows a average cooling energy saving of ∼29 % in buildings across China. The recyclable cooling paper with high cooling capability and scalability, as well as environmental friendliness, shows promising potential for sustainable energy-efficient buildings. [ABSTRACT FROM AUTHOR]

[Display omitted] • BCM-nZVI exhibit adsorption capacity of 134 mg·g−1 and Cd2+ removal rate of 99.96%. • Cd2+ in water treated by BCM-nZVI is below drinking water standards (5 μg·L-1). • BCM-nZVI can be stored stably for 120 days without loss of activity. • The adsorption mechanism by reducing toxic Cd2+ to non-toxic Cd0 is revealed. Cadmium (Cd2+) ions in drinking water are typical heavy metal contaminants, even trace amounts of Cd2+ can accumulate in the body, leading to serious irreversible damage to human bones and kidneys. Herein, we propose an effective and green strategy for the deep removal of trace Cd2+ from water by dispersed loading of nanoscale zero-valent iron (nZVI) onto bacterial cellulose membranes (BCM). BCM-nZVI can effectively remove Cd2+ from water in a wide pH range (5–8) with 99.96% removal rate. Freundlich isotherm model and the pseudo-second-order model reveal the adsorption process with a maximum adsorption capacity of 134.0 mg·g−1 at 30 °C. Impressively, the Cd2+ concentration in actual Cd2+ containing drinking water is below the target of 5 μg·L−1 (drinking water standard in China, USA and EU) after treated by the BCM-nZVI, and no additional pollutants are introduced. The excellent stability (stored stably for 120 days) and economic cost analysis ($75.6 m−3 for Cd2+ containing drinking water) of BCM-nZVI indicated they are viable for practical application in actual water treatment. Most importantly, the reduction reaction and mechanism study of BCM-nZVI revealed that the toxic Cd2+ is converted into non-toxic Cd0 assisted by the hydrated electrons and it has been systemically verified in our paper. This work sheds light on BCM-nZVI can be used as an ideal green material to removal Cd2+ in trace amounts of actual drinking water with high-efficiency, economical, environmentally friendly and has great potential for application in real environments. [ABSTRACT FROM AUTHOR]

• Microstructures of the outcrop/core kerogen were systematically characterized. • Differences in chemical structure between the outcrop/core kerogen were identified. • Realistic 2D/3D molecular models of the outcrop/core kerogen were constructed. • Validity of the proposed molecular models was verified by gravimetric adsorption. • Effect of the kerogen microstructure on CH 4 adsorption behavior was investigated. It has been known that adsorbed gas, mainly CH 4 , serves as the dominant source of shale gas yield in the middle and later stages of reservoir exploitation. Therefore, it is of great significance to study the microstructure of kerogen (organic matter rich in shale) and its effect on CH 4 adsorption characteristics. In this paper, for the first time, a comparative study was conducted to experimentally characterize the microstructure of both outcrop and core kerogen samples from Longmaxi Shale, Sichuan Basin, SW China, using 13C NMR, FTIR, and XPS. Great differences in the chemical structure such as carbon skeleton (e.g. , aromaticity, aliphatic branch) and heteroatoms (e.g. , distribution and proportion of various types of functional groups) between the two kerogen samples have been identified. Molecular models of the outcrop and core kerogen samples were constructed based on the experimental data, that is, C 237 H 219 O 21 N 5 S 4 for the former and C 239 H 175 O 27 N 5 S 4 for the latter. CH 4 adsorption isotherms obtained from gravimetric adsorption test and molecular simulation using proposed kerogen molecular models are in reasonable agreement with each other, especially at low-pressure range. Interestingly, the adsorption capacity of CH 4 in the core sample is found higher than that in the outcrop sample under the same condition, indicating the effect of kerogen microstructure on CH 4 adsorption behavior. As a result, to precisely evaluate the adsorbed gas content in shale gas reservoirs, it is strongly recommended to use a core sample rather than an outcrop sample. [ABSTRACT FROM AUTHOR]

[Display omitted] • A copolymer hydrogel was fabricated to harvest oceanic energy. • Ionic concentration was main driving force for continuous electricity generation. • This device produced a power density of 89.4 µW cm−2 in real seawater. • The series connection of six devices could power commercial electronic devices. Micro/nano fluidic electricity generation systems based on solid–liquid interface interaction to harvest energy from water in nature offer a potential green and clean electricity generation method. However, the performances of electricity generation were limited in salt solutions. In this paper, we prepared an extraordinary-performance hydrogel through ultraviolet polymerization for the access of ion concentration energy in seawater. This copolymer hydrogel made of AAm/AA (acrylamide/acrylic acid) provides a negatively charged three-dimensional transport network with micro/nano porous channels, which exhibits extraordinary ion selectivity in high ion concentration solutions. The experimental results show that this electricity generation device with intrinsic micro/nano pores can generate a continuous open-circuit voltage of 0.37 V, a short-circuit current of 116 μA, and a power density of 89.4 µW/cm2 from seawater (the Yellow Sea in China). The output current and power can be maximally more than 100 times and 50 times higher than the existing results. Through the series connection of six devices, the overall output is sufficient to supply stable power to directly light up small commercial electronic devices. Our study presents a new research idea for the development of low-cost, environmentally friendly, and self-powered devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ReaxFF MD simulation and experiments of amoxicillin SCWG were conducted. • The decomposition of amoxicillin in supercritical water includes three stages. • The detailed process of amoxicillin decomposition in SCW was revealed. • The dual effect of OH radicals on the amoxicillin decomposition in SCW was found. • Reaction networks for nitrogen and sulfur conversion in SCW were obtained. The abuse of antibiotics in China has aroused widespread concern, and the resistance genes of antibiotics in the natural environment seriously threaten human health. The supercritical water gasification (SCWG) technology is a clean and efficient technology for the treatment of antibiotic wastewater. In this paper, amoxicillin is selected as the representative antibiotic in wastewater, and the detailed mechanisms of amoxicillin decomposition in supercritical water (SCW) are studied by ReaxFF reactive molecular dynamics (MD) simulation. The results show that the decomposition process of amoxicillin in SCW includes carbon ring opening, carbon chain breaking and small molecular compounds conversion. The molecular vibration leads to the breaking of C N and C S bonds. The OH radical is vital to the ring opening of benzene ring and the breaking of carbon chain. However, the yield of NO increases with increasing OH radical concentrations. The ReacNetGenerator tool is used for the first time to analyze the migration path of nitrogen and sulfur in the SCWG system. It shows that H 2 has a great effect on the transformation of sulfur, and OH radicals dominate the transformation of nitrogen. Decreasing the reaction time and the concentration of OH radicals result in inhibiting the NO production. This study will provide a theoretical guidance for understanding SCWG process of antibiotic-containing wastewater. [ABSTRACT FROM AUTHOR]

Abstract: The effect of pH and coagulant dosage on the coagulation performance of aluminum sulphate and polyaluminum chloride (PAC) with respect to the treatment of Yellow River water was investigated in this paper. The separation and measurement of residual aluminum (Al) speciation were also conducted. The results indicated that PAC showed superior coagulation performance compared to that of Al2(SO4)3 in most cases during the Yellow River water treatment. At a dosage of 15mg/L as Al2O3, PAC achieved an optimum removal efficiency of turbidity, UV254 and DOC of 96.3, 57.1, 32.7%, respectively, and Al2(SO4)3 also achieved an optimum removal efficiency of turbidity, UV254 and DOC of 94.5, 53.5 34.8%, respectively. For PAC and Al2(SO4)3, the optimum pH during the treatment of Yellow River water could be determined at 6.0. Different residual Al speciation exhibited different trends with dosage and pH variation. For the two coagulants studied, no matter the dosage or pH, the majority of residual total Al existed most in the form of total dissolved Al, among which, dissolved organically bound Al was the predominant speciation. Most of the dissolved monomeric Al in the effluent was dissolved inorganically bound monomeric Al. PAC showed lower concentration for the several kinds of residual aluminum species, except the dissolved organically bound Al; and PAC could effectively reduce the concentration of dissolved monomeric Al. [Copyright &y& Elsevier]