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X-ray mirrors with high focusing performance are extensively used in the synchrotron radiation field. Especially for vertical reflecting bendable mirrors, many elements such as gravity, extended parts used for the bending mechanism, etc., usually affect the surface shape precision. There are no effective methods to remove all these errors at this point. However, an iteration method can be adopted to solve this problem. In this paper, a novel, to the best of our knowledge, iteration method on decreasing the error between the practice surface shape and the desired one is proposed. Not only can the precision of the surface shape be realized by this method, but also computational efficiency. Errors induced by gravity can be compensated for by an analytical method, while errors caused by the extended parts should be eliminated by a numerical method. Therefore, two main kinds of errors—gravity and parts of clamping—can be removed by iteration. Some examples are presented to illustrate the advantages of this method by comparison with the regular one.

Silicon (Si) is considered to be the most promising anode material to replace graphite due to its higher theoretical capacity. Nanotechnology has played an important role in addressing the serious volume changes that occur during the lithium process of Si anode removal. However, the development of Si anodes has not yet reached the industry standard for the next generation of commercial lithium-ion batteries. Nowadays, with the increasing requirements for battery energy density in diverse industries, the use of silicon anode materials to increase energy density, co-utilization of Si, graphite, new binders, and electrolytes has become a commercially viable method to achieve high energy. Therefore, in this review, we emphasize the necessity of using Si/graphite anodes, new binders, and electrolytes at the same time in commercialization and carefully review the development of Si/graphite anodes. The typical Si anode mixed graphite electrode is discussed, and various strategies for constructing Si/graphite composite materials are organized according to their synthesis method. It is particularly noteworthy that we systematically introduce the key factors for the co-utilization of Si/graphite anodes, new binders, and electrolytes. Finally, some suggestions on the practical application of Si/graphite anodes are given.

To relieve the volume expansion of silicon during the lithium insertion/desertion process, we designed fluffy rice carbon/nano-Si@C (FRC/NP-Si@C) composites with a stable structure via spray drying, a large-scale produced low-cost approach. Nanosilicon particles are fixed in robust microspheres assembled from FRC and pitch carbon while forming three-dimensional (3D) conducting nanosized porous channels. FRC/NP-Si@C composites, as anodes for lithium-ion batteries, display outstanding cycling and rate performances at room temperature owing to their special structure. They exhibit a reversible capacity of 600 mAh g–1at 0.1 A g–1after 200 cycles as well as stable capacities of 1688.2 and 579.8 mAh g–1at current densities of 0.1 and 1.6 A g–1, respectively, indicating their use as alternative anode materials for lithium-ion batteries (LIBs).

Lithium–sulfur (Li–S) batteries have been attracting great attention as promising rechargeable batteries because of their large specific capacity and high energy density. However, some technical problems still limit the commercialization value of Li–S batteries such as poor electrical conductivity, shuttle effects, and volume expansion. To overcome the aforementioned issues, N-doped carbon composites were synthesized via a one-step hydrothermal method. To obtain different N-doping configurations, a carbon precursor was annealed at different heating rates, resulting in different N-containing properties. The cell with the most content of pyridinic-N delivered the highest initial discharge capacity of ∼1121 mAh g–1, and the specific capacity still retained 605 mAh g–1at 200 mA g–1after 100 cycles. It was concluded that pyridinic-N has the most significant effect on immobilizing the soluble lithium polysulfides, which stabilized the cycle of Li–S batteries.

Bismuth nanoparticles were synthesized in three-dimensional (3D) network carbon nanofibers by the electrospinning and carbonization method. The bionic structures with cucumber-shaped carbon nanofibers@Bi nanoparticles (CCNs@BiNs) have flexibility and a self-supporting backbone, which can directly be used as anode materials for lithium-ion batteries (LIBs). The carbon shells that wrap bismuth nanoparticles can effectively buffer the volume expansion during the lithiation process. Owing to the special structure and pseudocapacitive effect, the CCNs@BiNs electrodes can deliver a superb cycling capacity of 322 mAh g–1at 0.25 A g–1after 500 cycles. The rate capability with high recoverability demonstrates a capacity of 450 mAh g–1when the current density returns to 0.1 A g–1. The binder-free and foldable CCNs@BiNs will have potential for use in energy storage devices with high demand and requirement of flexibility and long cycling.

Efficiently storing electricity generated from renewable resources and desalinating brackish water are both critical for realizing a sustainable society. Previously reported desalination batteries need to work in alternate desalination/salination modes and also require external energy inputs during desalination. Here, we demonstrate a novel zinc–air battery-based desalination device (ZABD), which can desalinate brackish water and supply energy simultaneously. The ZABD consists of a zinc anode with a flowing ZnCl2anolyte stream, a brackish water stream, and an air cathode with a flowing NaCl catholyte stream, separated by an anion-exchange membrane and a cation-exchange membrane, respectively. During the discharging, ions in brackish water move to the anolyte and catholyte, and they return to the feed steam during charging. The ZABD can desalt brackish water from 3000 ppm to the drinking water level at 120.1 ppm in one step and concurrently provide an energy output up to 80.1 kJ mol–1under a discharge current density of 0.25 mA cm–2. Further, the ZABD can be charged/discharged over 20 cycles without significant performance deterioration, demonstrating its reversibility. Moreover, the desalination performances can be adjusted by varying current densities and are also influenced by the initial concentration of salt feeds. Besides, two ZABD devices were connected in series to drive 60 light-emitting diodes during the salt removal process without external power supply over 2000 min. Overall, this ZABD system demonstrates the potential for simultaneous water desalination and energy supply, which is suitable for many urgent situations.

Gypsum is the most common sulfate mineral on Earth’s surface and is the dominant solid byproduct in a wide variety of mining and industrial processes, thus representing a major source for heavy metal(loid) contamination, including selenium. Gypsum crystals grown from the gel diffusion technique in 0.02 M Na2SeO4solution at pH 7.5 and 0.02 M Na2SeO3solutions at pH 7.5 and 9.0 contain 828, 5198, and 5955 ppm Se, respectively. Synchrotron Se K-edge X-ray absorption spectroscopic analyses show that selenite and selenate are the dominant species in Se4+- and Se6+-doped gypsum, respectively. The single-crystal EPR spectra of Se4+- and Se6+-doped gypsum after gamma-ray irradiation reveal five selenium-centered oxyradicals: SeO2–(I), SeO2–(II), SeO2–(III), SeO3–, and HSeO42–. The former three radicals provide unequivocal evidence for the substitution of their paramagnetic precursor SeO32–for SO42–in the gypsum structure, while the latter two confirm the replacement of SeO42–for SO42–. These results demonstrate that gypsum has a significant capacity for sequestrating both selenite and selenate in the structure but has a marked preference for the former, thus confirming important controls on the mobility and bioavailability of selenium oxyanions and pointing to optimal applications of gypsum for remediating selenium contamination under neutral to alkaline conditions.

The separations of quaternary reversible reactions with the most unfavorable ranking of relative volatilities (i.e., the two reactants are the lightest and heaviest components and the two products in between) require a reactive distillation column, followed by one or two conventional distillation columns. The multiple-column structure reflects not only a high energy intensity in the reaction operation and separation operation involved but also a great potential of process intensification in process development. With reference to a two-column system involving a reactive distillation column with an external recycle and a conventional distillation column (ER-RDC + CDC), a kind of reactive double dividing-wall distillation column (R-DDWDC) is derived via careful coordination and mass and thermal coupling between the ER-RDC and CDC. Closely dependent upon the magnitude of the reaction thermal effect, the left dividing wall is located either at the top or at the bottom. In addition to allowing the mass and thermal coupling between the ER-RDC and CDC, it facilitates primarily the reaction operation in the reactive section. The right dividing wall is located at the middle to fully strengthen the mass and thermal coupling not only between the ER-RDC and CDC but also between the separation operations included. The derived R-DDWDC features essentially the greatest degree of process intensification and becomes consequently the most thermodynamically efficient scheme in the separations of quaternary reversible reactions with the most unfavorable ranking of relative volatilities. The derived R-DDWDC is evaluated in terms of two examples, involving, respectively, the separations of ideal exothermic and endothermic quaternary reversible reactions with the most unfavorable ranking of relative volatilities. The derived R-DDWDC is found to be much more energy efficient than the ER-RDC + CDC, the reactive single dividing-wall distillation column, and those R-DDWDCs with different configurations. These outcomes demonstrate that the derived R-DDWDC is a much competitive alternative for the separations of quaternary reversible reactions with the most unfavorable ranking of relative volatilities. They also highlight the feasibility and effectiveness of the proposed strategy for process synthesis and design, that is, when the reaction processed is exothermic, the optimum R-DDWDC must come from one of R-DDWDC2 and R-DDWDC4; otherwise, the R-DDWDC4 remains to be the only possibility.

Due to the topological structure of double columns and multiple separating sections in dividing-wall distillation columns (DWDCs), the development of vapor recompressed dividing-wall distillation columns (DWDC-VRHPs) represents a challenging issue with great complexities and tediousness. For the separations of light-component dominated and wide boiling-point ternary mixtures, because the purification of the light-component from the intermediate- and heavy-components incurs the primary energy dissipation, the application of vapor recompressed heat pumps (VRHP) should be aimed to reduce the irreversibility and this leads to the generation of the optimum topological structures of the DWDC-VRHPs, i.e., a DWDC plus a two-stage VRHP. The first-stage VRHP is to preheat feed, not only taking the advantages of the small temperature elevation available but also favoring the mass transfer between the vapor and liquid phases through feed splitting. The second-stage VRHP is to reduce further separation irreversibility. The philosophy can be applied to any DWDCs no matter where the dividing wall locates. Two case studies on the separations of ternary mixtures of benzene, toluene, and o-xylene and n-pentane, n-hexane, and n-heptane demonstrate the economic optimality of the proposed DWDC-VRHPs and reveal the inherent interplay between internal and external process integration.

In our recent work, the arrangement of multiple reactive sections is found to greatly enhance the steady-state performance of reactive distillation columns disproportionating trichlorosilane to silane. In the current research, process dynamics and controllability are studied through in-depth comparative analysis of open-loop and closed-loop behaviors between three reactive distillation columns with, respectively, a single reactive section (RDC-SRS), double reactive sections (RDC-DRS), and triple reactive sections (RDC-TRS). In the regulation path, although the arrangement of double and triple reactive sections reduces slightly the process gains between the bottom product composition and reboiler heat duty in the RDC-DRS and RDC-TRS, it helps to alleviate the coupling between the bottom product composition and reflux flow rate, thereby gaining increases in process controllability as compared with the RDC-SRS. In the disturbance path, the arrangement of double and triple reactive sections results in no intensified sensitivities to the disturbances from feed flow rate and composition. The closed-loop operation tests coincide with the open-loop analysis and demonstrate that the RDC-TRS and RDC-DRS exhibit substantially improved antidisturbance and set-point tracking capabilities as compared with the RDC-SRS. These outcomes highlight evidently the great importance of arranging multiple reactive sections to the dynamics and controllability of reactive distillation columns separating reacting mixtures with unfavorable and complicated reaction kinetics.

The conventional method for configuring double temperature difference control (DTDC) schemes relies on sensitivity analysis (SA) and singular value decomposition (SVD) analysis, respectively, to determine sensitive and reference stages. Since no considerations are given at all to the interactions between the synthesized double temperature differences (DTDs) and to the coordination between the upper and lower temperature differences (TDs) subtracted in each synthesized DTD, the conventional method may lead to DTDC schemes that fail to secure tight product quality control of distillation columns. In this article, a novel method is proposed that employs a newly defined metric in our recent work, the averaged absolute variation magnitudes (ASVM), to determine the two reference stages in each DTDC loop. The ASVM measures the variations of TDs between the sensitive stage and the remaining ones with the assumption of complete rejection of all disturbances concerned and can thus reflect the inherent characteristics of coupling between the controlled product qualities. For each DTDC loop, while the first reference stage should be chosen to cope with its coupling with the other control loops, the second reference stage should be to coordinate the two TDs involved, thereby yielding a favorable effect to the inference of the controlled product qualities. Four example systems, including one conventional distillation column separating a binary mixture of ethanol and butanol, two conventional distillation columns separating a ternary mixture of ethanol, propanol, and butanol, and one dividing-wall distillation column separating a ternary mixture of ethanol, propanol, and butanol, are used to assess the proposed method by means of in-depth comparison with the conventional method. While they display comparable dynamic performances, the former leads to considerably smaller steady-state deviations in the controlled product qualities than the latter. These striking outcomes demonstrate evidently that the proposed method can be a promising alternative for the pursuit of tight temperature inferential control of various distillation columns.

As an efficient alternative copper (Cu) source, copper nanoparticles (nano-Cu) have been widely supplemented into animal-producing food. Therefore, it is necessary to assess the effect of nano-Cu exposure on the biological health risk. Recently, the toxic effects of nano-Cu have been confirmed but the underlying mechanism remains unclear. This study reveals the impact of nano-Cu on endoplasmic reticulum autophagy (ER-phagy) in chicken hepatocytes and further identifies Drp1 and its downstream gene FAM134B as crucial regulators of nano-Cu-induced hepatotoxicity. Nano-Cu exposure can induce Cu ion overaccumulation and pathological injury in the liver, trigger excessive mitochondrial fission and mitochondria-associated membrane (MAM) integrity damage, and activate ER-phagy in vivo and in vitro. Interestingly, the knockdown of Drp1 markedly decreases the expression of FAM134B induced by nano-Cu. Furthermore, the expression levels of ATL3, CCPG1, SEC62, TEX264, and LC3II/LC3I induced by nano-Cu exposure are decreased by inhibiting the expression of Drp1. Simultaneously, the inhibition of FAM134B effectively alleviates nano-Cu-induced ER-phagy by downregulating the expression of ATL3, CCPG1, SEC62, TEX264, and LC3II/LC3I. Overall, these results suggest that Drp1-mediated impairment of MAM integrity leads to ER-phagy as a novel molecular mechanism involved in the regulation of nano-Cu-induced hepatotoxicity. These findings provide new ideas for future research on the mechanism of nano-Cu-induced hepatotoxicity.

Diverse microorganisms live as biofilm in the mouth accounts for oral diseases and treatment failure. For decades, the prevention and treatment of oral biofilm is a global challenge. Antimicrobial photodynamic therapy (aPDT) holds promise for oral biofilm elimination due to its several traits, including broad-spectrum antimicrobial capacity, lower possibility of resistance and low cytotoxicity. However, the physicochemical properties of photosensitizers and the biological barrier of oral biofilm have limited the efficiency of aPDT. Nanomaterials has been used to fabricate nanocarriers to improve photosensitizer properties and thus enhance antimicrobial effect. In this review, we have discussed the challenges of aPDT used in dentistry, categorized the nanomaterial-delivery system and listed the possible mechanisms involved in nanomaterials when enhancing aPDT effect.

Pollutants contained in wastewater pose serious harm to the environment. Graphene-based water treatment materials show significant advantages in wastewater treatment. However, with the development of graphene-based materials, its progress in water treatment has reached a bottleneck. The challenge lies in effectively enhancing its performance in water treatment and ensuring its practicality. By employing biomimetic approaches, some exceptional properties and structures found in nature can be mimicked in graphene materials, effectively enhancing graphene's adsorption and mechanical properties. Current biomimetic methods include biomimetic mineralization, self-assembly, and templating. unfortunately, all of the above methods suffer from the disadvantages of complexity and poor bionic effect. Nevertheless, 3D printing, a form of additive manufacturing (AM) technology, offers integrated molding and excellent biomimetic performance in creating biomimetic materials. This paper will cover the following aspects: (1) an overview of objects suitable for bionics in terms of functional and structural aspects, along with their properties, and a discussion of various bionic objects combined with graphene materials in water treatment and related research; (2) a comparison of different methods for preparing graphene-based bionic materials; (3) an examination of the current drawbacks and limitations of graphene-based biomimetic materials; and (4) a conclusion and future prospects, exploring the potential of using 3D printing technology to produce graphene biomimetic materials. This review aims to serve as a guide for effectively leveraging natural inspirations to create graphene-based biomimetic materials and enhance graphene properties.

The solid–liquid phase equilibrium data of theophylline and isonicotinamide in selected solvents (isopropanol, N,N-dimethylformamide, and n-pentanol) were determined by using the static method at 298.15 and 308.15 K under 101.325 kPa. The ternary phase diagram was plotted, and it was concluded that it is an asymmetric phase diagram. The mechanism of solid-phase formation of cocrystals during the determination of the ternary phase diagram is discussed. Excessive amounts of THE and INA cause the system to become supersaturated. As the cocrystal forms, the solubility of THE and INA decreases. When the system is on the solvation curve of the cocrystal, the activity coefficients of THE and INA drop to critical values and cocrystal formation stops. Based on the analysis of phase solubility diagrams for cocrystals, two routes for obtaining the cocrystal of THE-INA from solution have been proposed and validated. For route 1, concentrations of THE and INA in the solution are adjusted to the appropriate concentrations, and then, solvent evaporation is performed to achieve crystallization. For route 2, an amount of THE was added to a highly concentrated INA solution. The variation of the main constitutive forces of cocrystal formation is explored by molecular simulation simulations. The types of interaction forces and their interaction energies in ternary systems are identified. In addition, the melting temperature and enthalpy of fusion of the THE-INA cocrystal obtained during ternary phase diagram determination were determined to be 462.26 K (onset) and 131.69 J/g, respectively.

Rock cuttability has great influence on the rock excavation efficiency of TBM (tunnel boring machine). In order to evaluate rock cuttability in real time, quickly, accurately and efficiently during TBM excavating, the relevant excavation parameters of Zagros, Kerman and Bazideraz tunnels were first collected. Then, the regression analyses between excavation parameters and rock cuttability were carried out. The two-dimensional regression analyses studied the relationship between operating parameters (thrust Fand rotation speed RPM) and the characterization parameters (torque Tand penetration rate PR). The three-dimensional regression analyses were utilized to create the PRand specific energy SEmodels based on operating parameters. The result shows that the established three-dimensional regression models have good prediction performance, and its performance is superior to two-dimensional models. Moreover, the prediction model of uniaxial compressive strength UCSand the classification model of rock cuttability were founded based on SE. The rock cuttability is divided into three levels, namely, easy (level 1), medium (level 2), and poor (level 3), in which the corresponding SEranges are 0 to 6, 6 to 10 and exceeds 10 kWh·m−3, respectively. Finally, the intelligent algorithms, combined with excavation parameters, were introduced to establish UCSprediction model and rock cuttability classification model, and the good prediction performance was achieved. The above studies can provide necessary references and ideas for real-time, rapid, accurate and effective evaluation of rock cuttability based on TBM excavation parameters, and has certain guiding significance for engineering application.

With the large-scale mining of coal resources, the huge economic losses and environmental problems caused by underground coal fires have become increasingly prominent, and the research on the status quo and response strategies of underground coal fires is of great significance to accelerate the green prevention and control of coal fires, energy conservation and emission reduction. In this paper, we summarized and sorted out the research status of underground coal fires, focused on the theoretical and technical issues such as underground coal fire combustion mechanism, multiphysics coupling effect of coal fire combustion, fire prevention and extinguishing technology for underground coal fires, and beneficial utilization technology, and described the latest research progress of the prevention and control for underground coal fire hazards. Finally, the key research problems in the field of underground coal fire hazards prevention and control were proposed in the direction of the basic theory, technology research, comprehensive management and utilization, with a view to providing ideas and solutions for the management of underground coal fires.

A comprehensive evaluation method is proposed to analyze dust pollution generated in the production process of mines. The method employs an optimized image-processing and deep learning framework to characterize the gray and fractal features in dust images. The research reveals both linear and logarithmic correlations between the gray features, fractal dimension, and dust mass, while employing Chauvenel criteria and arithmetic averaging to minimize data discreteness. An integrated hazardous index is developed, including a logarithmic correlation between the index and dust mass, and a four-category dataset is subsequently prepared for the deep learning framework. Based on the range of the hazardous index, the dust images are divided into four categories. Subsequently, a dust risk classification system is established using the deep learning model, which exhibits a high degree of performance after the training process. Notably, the model achieves a testing accuracy of 95.3%, indicating its effectiveness in classifying different levels of dust pollution, and the precision, recall, and F1-score of the system confirm its reliability in analyzing dust pollution. Overall, the proposed method provides a reliable and efficient way to monitor and analyze dust pollution in mines.

Arsenic is ubiquitous in many natural systems and poses great risk to human health. Coal fly ash is a waste by-product of thermal power plants that may cause serious environmental problems. To reduce environmental hazards and realize high-value utilization of coal fly ash, it was characterized using the scanning electron microscopy, Brunauer–Emmet–Teller, and powder X-ray diffraction methods, and the arsenate (As(V)) and arsenite (As(III)) removal performance of coal fly ash used as an adsorbent from aqueous solutions was investigated using batch experiments. Adsorption kinetics study revealed that the adsorption of As(V) and As(III) by fly ash was fast in the first 4 h and equilibrium was achieved within 48 h at pH 5.0 with an initial arsenic concentration of 1 mg/L and an adsorbent dose of 4 g/L. The adsorption kinetics are well described by the pseudo-second-order rate equation model, with high coefficients of determination (R2) of 0.9991 and 0.9925 for As(V) and As(III) adsorption, respectively. The Langmuir adsorption isotherms of arsenic adsorption indicated that the highest adsorption capacities of As(V) and As(III) at pH 5.0 were 666.67 and 232.56 mg/kg, respectively. The results of the arsenic adsorption edges conducted at different pH values from 3 to 11 with initial arsenic concentration of 1 mg/L and adsorbent dose of 4 g/L revealed that the removal of As(V) was obviously more than that of As(III) under the same conditions, with respect to the same pH. Different from the sharp maximum adsorption at pH around 5.0 on the As(V) adsorption edge, the As(III) adsorption maximum is broad, occurred in the pH range of approximately 5.0 to 7.0. The significant differences in the adsorption of As(V) and As(III) on fly ash could be due to the discrepant electrostatic interaction between Al-based hydroxyl groups on the surface of fly ash and arsenic species in aqueous solution. Furthermore, this approach provides a possible method for treating arsenic wastewater and potential application for the reuse of coal fly ash generated by other industrial activities.

Temperature inferential control (TIC) is studied for a reactive distillation column with double reactive sections (RDC-DRSs) processing a hypothetical two-stage consecutive reversible reaction (A + B ↔ C + D, C + B ↔ E + D with αD > αB > αC > αA > αE). Because of the complicated dynamic behaviors, the controlled stages by sensitivity analysis lead to great steady-state deviations (SSDs) in top and bottom product purities. Since TIC involves considerably reduced settling times in comparison with direct composition control, small SSDs in product qualities correspond generally to small transient deviations (TDs) in product qualities. An objective function that measures SSDs in product qualities is formulated to represent the performance of a TIC system and an iterative procedure is devised to search for the best control configuration. The application of the procedure to the RDC-DRS gives considerably suppressed TDs and SSDs in top and bottom product qualities as compared with the one by sensitivity analysis. The method is simpler in principle and less computationally intensive than the current practice. These striking outcomes show the effectiveness of the proposed principle for the development of TIC systems for complicated reactive distillation columns.

Although dividing wall technology is very effective for process intensification of distillation, the resultant dividing-wall distillation columns (DWDCs) exhibit strongly interactive and highly nonlinear behaviors, which may pose great challenges to process operations. Proportional–integral (PI) controllers can stabilize the operation of the DWDC, but their performances are frequently far from satisfactory. Model predictive control (MPC) can potentially improve performance sharply, but the stringent requirements on the qualities of the embedded model considerably lower its robustness. To suppress these two deficiencies, in this work a cascaded control structure by combining the MPC and PI controllers is proposed for the DWDC. The PI controllers regulate the stage temperature in the inner layer, serving to quickly stabilize the DWDC, while the MPC directly controls the product compositions in the outer layer, addressing the strongly interactive and highly nonlinear behaviors of the DWDC. Two typical cases, that is, a three-product Petlyuk DWDC and a four-product Kaibel DWDC, and five control schemes, that is, two impurity composition controls (PI-ICC and MPC-ICC), two purity composition controls (PI-PCC and MPC-PCC), and one pure temperature control PI-TC (which represents the case wherein MPC in the outer layer fails to work), are studied to evaluate the feasibility and effectiveness of the proposed control structure. It is found that the cascaded MPC/PI controllers (i.e., MPC-ICC and MPC-PCC) substantially outperform the pure PI controllers (i.e., PI-ICC and PI-PCC), with lower maximum and steady-state deviations, shortened settling times, and suppressed oscillations. In the case of failure of the MPC, the cascaded MPC/PI controller can still maintain stable operation of the DWDC. These outcomes highlight that the combination of MPC and PI controllers can be a potential method for the operation of highly interactive and complicated DWDCs.

Chloride-ion battery is considered as the promising electrochemical system due to its high energy density in theory. However, aqueous chloride-ion redox materials are limitedly reported owing to their instability or dissolution in aqueous electrolyte. Here, we synthetize a new electrochemical chloride-ion material, Sb4O5Cl2, investigate its electrochemical performance in aqueous NaCl electrolyte, and assemble into aqueous chloride-ion battery with silver as cathode. During the battery charge process, Sb4O5Cl2anode electrochemically releases chloride ions, which are captured by Ag cathode with the formation of silver chloride while the discharging reverses the process. The battery demonstrates favorable electrochemical performance. With current density of 600 mA g–1, the battery discharge capacity of 34.6 mAh g–1can be maintained for 50 cycles. This work is greatly significant for the development of anion electrochemical energy storage.

Genetic variants near the tumor necrosis factor-α-induced protein 3 gene (TNFAIP3) at the chromosomal region 6q23 demonstrated significant associations with multiple autoimmune diseases. The signals of associations have been explained to the TNFAIP3gene, the most likely causal gene. In this study, we employed CRISPR/cas9 genome-editing tool to generate cell lines with deletions including a candidate causal variant, rs6927172, at 140 kb upstream of the TNFAIP3gene. Interestingly, we observed alterations of multiple genes including IL-20RAencoding a subunit of the receptor for interleukin 20. Using Electrophoretic mobility shift assay (EMSA), Western blotting, and chromatin conformation capture we characterized the molecular mechanism that the DNA element carrying the variant rs6927172 influences expression of IL-20RAand TNFAIP3genes. Additionally, we developed a new use of the transcription activator-like effector (TALE) to study the role of the variant in regulating expressions of its target genes. In summary, we generated deletion knockouts that included the candidate causal variant rs6927172 in HEK293T cells provided new evidence and mechanism for IL-20RAgene as a risk factor for multiple autoimmune diseases.

Sulfidization of nano-ferrihydrite (nano-Fhy) by S(−ii) plays an important role in Fe and As biogeochemistry in wetland soils, sediments, and aquifers. However, during early stages, the changes in speciation and redistribution of adsorbed As remain unclear. This study investigated the reduction and transformation of As-bearing nano-Fhy and subsequent As repartitioning among secondary phases induced by an environmentally relevant concentration of sulfide (S(−ii)) (Fe/S ratio = 80, S(−ii) concentration = 0.5 mM) at pH 7. Chemical analysis indicated that the mobility of As associated with iron oxyhydroxide minerals was greatly reduced during the transformation of nano-Fhy. The initially adsorbed As was partially (60–90%) transformed to a phosphate-unextractable phase and approximately 50–90% of As(iii) was oxidized to As(v) during recrystallization of nano-Fhy to lepidocrocite and goethite. The intermediate Fe species formed during electron (e−) transfer from S(−ii) to Fe(iii) and subsequent e−transfer between Fe(ii) and Fe(iii) may be responsible for oxidization of As(iii). The S K-edge X-ray absorption near edge structure (XANES) results showed that S(−ii) could be oxidized to multiple valence states and its evolution was strongly affected by the concentration and speciation of As. As(iii) can inhibit the oxidation of S(−ii) to sulfate, whereas the presence of As(v) may promote the oxidation of S(−ii) to sulfate compared with the system without As. These findings have important environmental implications for As, Fe, and S redox cycling during early stage sulfidization of nano-Fhy.

The adsorption and desorption behavior of arsenate (As(v)) at the ferrihydrite/water interface in nature is determined by its complexation structure. However, current understanding of the coordination environment of As(v)–ferrihydrite complexes obtained from synchrotron extended X-ray absorption fine structure (EXAFS) fitting is still controversial due to the lack of precise Debye–Waller (DW) factors. We computed the DW factors of bidentate binuclear (BB) and monodentate mononuclear (MM) As(v)–ferrihydrite complexation models by using ab initiodensity functional theory (DFT) calculations. Using the ab initioDW factors, the EXAFS spectra of the As–ferrihydrite samples synthesized at pH 8 and 9 were better fitted with MM models than with BB models. Specifically, the BB model significantly overestimated the amplitude of the As–Fe shell in R-space, whereas the MM model perfectly simulated it. Our results supported that ferrihydrite adsorbs As(v) dominantly through MM complexes at weakly alkaline pH values. These findings are of significance for understanding the adsorption/desorption processes of As(v) at the ferrihydrite/water interface and have far-reaching implications for the geochemical behavior of As in aqueous environments.

The exact solution of the generalized Peierls equation is presented and proved for arbitrary n-fold screw dislocation. The displacement field, stress field and the energy of the n-fold dislocation are also evaluated explicitly. It is found that the solution defined on each individual fold is given by the tail cut from the original Peierls solution. In viewpoint of energetics, a screw dislocation has a tendency to spread the distribution on all possible slip planes which are contained in the dislocation line zone. Based on the exact solution, the approximated solution of the improved Peierls equation is proposed for the modified γ -surface. [ABSTRACT FROM AUTHOR]

This work is focused on the relationship between electrochemical performance and morphology of LiNi1/3Co1/3Mn1/3O2(NCM) in an aqueous rechargeable lithium battery, and provides a reference for the selection of novel battery materials. In this work, NCM microrods, microspheres, and nanoblocks were successfully synthesized by solvothermal, coprecipitation, and sol–gel methods, respectively. Of the three samples, NCM nanoblocks, which are formed by agglomeration of a large number of nanoparticles, show the best electrochemical performance. During cycling, the NCM nanoblock exhibits an initial discharge capacity of 137.4 mAh g−1and an impressive capacity of 130.8 mAh g−1after 20 cycles at a current density of 1C (=160 mA g−1). Even at a high current density of 50C, this NCM nanoblock provides a capacity of 50.1 mAh g−1, which shows the great potential of the nanoblock as a cathode in aqueous rechargeable lithium‐ion batteries. Nano versus micro: A study on the relationship between the structure and performance of LiNi1/3Co1/3Mn1/3O2(NCM) in aqueous rechargeable lithium batteries (ARLBs) is reported. Nanoblocks of NCM as a cathode material exhibit the best cycling and rate performance, when compared with NCM microrods and microspheres.

Arsenic (As), barium (Ba), and sulfate (SO42−$\begin{array}{} \displaystyle \rm SO_4^{2-} \end{array} $), coexisting in natural and mining impacted environments, possibly lead to As-barite coprecipitation. This work investigated the coprecipitation of Ba2+, SO42−$\begin{array}{} \displaystyle \rm SO_4^{2-} \end{array} $, and AsO43−$\begin{array}{} \displaystyle \rm AsO_4^{3-} \end{array} $[As(V)] and the incorporation of As(V) into the barite structure. The As(V) content in the coprecipitates increased with pH and the initial aqueous As(V) concentration. At pH ≤ 5, As(V) was dominantly fixed through isomorphic substitution for SO42−$\begin{array}{} \displaystyle \rm SO_4^{2-} \end{array} $in the barite structure (<0.32 wt%). At pH > 5, barium (hydrogen) arsenate constituted an appreciable fraction of As(V)-bearing species in addition to the incorporated As(V). FTIR spectroscopy indicated that As(V) in the coprecipitate occurred as mixed phases and the As(V) species incorporated into the barite structure was dominated by HAsO42−$\begin{array}{} \displaystyle \rm HAsO_4^{2-} \end{array} $species. EXAFS analysis gave As-O and As-OH bond lengths of 1.67 and 1.75 Å for HAsO42−$\begin{array}{} \displaystyle \rm HAsO_4^{2-} \end{array} $in barite structure, respectively. The FPMS structural refinement reproduced well the As K-edge XANES spectrum and gave bond lengths of As-O at 1.63, 1.64, 1.68, and 1.75 Å with an average bond length of 1.68 ± 0.05 Å in HAsO42−$\begin{array}{} \displaystyle \rm HAsO_4^{2-} \end{array} $doped barite structure. The findings are of significance for understanding the geochemical cycle of As in As(V), Ba2+, and SO42−$\begin{array}{} \displaystyle \rm SO_4^{2-} \end{array} $coexisting systems.

When acid phosphogypsum (APG) is recycled as aggregate of cemented backfill in mines, pretreatment is usually needed to reduce its adverse impact on the backfill. In this study, a new approach of using a neutral salt (CaCO3) to pretreat APG has been proposed to enhance the strength development of the cemented PG backfill. The role of CaCO3in cemented PG backfill acting as a reactant is explored. In the pretreatment stage, CaCO3reacted with the residual acid in PG, and the generated calcium ions could solidify the impurities, such as soluble phosphate and fluoride, with solidification rates reaching 90% and 99%, respectively. This neutral modifier buffered pH values of PG aggregate from 1.8 to about 5.0, and excess dosage of CaCO3did not adjust the pH value of aggregate to an excessively high level. Hence, there was no interference with the hydration reaction of the binder (cement). Using PG pretreated with CaCO3as aggregate for cemented backfill effectively accelerated the setting process of backfill and increased the unconfined compressive strength (UCS) of the backfill matrix from 0.14 MPa to 2.27 MPa at 28-day age. The present results suggest that CaCO3pretreatment is an effective way to improve the accessibility of PG as aggregate, thus significantly increasing the utilization rate of PG and enhancing the backfill performance.

Hierarchical CoMn2O4microspheres assembled by nanoparticles have been successfully synthesized by a facile hydrothermal method and a subsequent annealing treatment. XRD detection indicate the crystal structure. SEM and TEM results reveal the 3-dimensional porous and micro-/nanostructural microsphere assembled by nanoparticles with a size of 20-100 nm. The CoMn2O4electrode show initial specific discharge capacity of approximately 1546 mAh/g at the current rates 100 mA/g with a coulombic efficiency of 66.7% and remarkable specific capacities (1029-485 mAh/g) at various current rates (100-2800 mA/g).

Because of the complicated interplay between the prefractionator and main distillation column involved, the black-hole problem might occur and prohibit the assignment of four specifications to dividing-wall distillation columns (DWDCs) (e.g., the three main product compositions plus an impurity ratio in the intermediate product), which lowers terribly process flexibility and operability. In this paper, a feed thermal condition adjustment strategy, achieved by the installation of a pre-heater in feed pipeline, is employed to eliminate the black-hole problem and serve to enhance process flexibility and operability. Through the strong influence to the overall mass and energy balance of the DWDC, the feed thermal condition adjustment can alter the interlinking flows between the thermally coupled prefractionator and main distillation column and work effectively to coordinate their relationship. A DWDC separating a benzene, toluene, and o-xylene mixture is chosen to ascertain the feasibility of the philosophy proposed. The static and dynamic studies demonstrate that the feed thermal condition adjustment is an effective way to refine process design and can completely eliminate the black-hole problem and elevate consequently process flexibility and operability.

In this work, the dynamics and operation of the totally reboiled reactive distillation columns are visualized in terms of transfer function based process models. This kind of processes is found to be characterized by under-damped step responses due to the special topological configuration and the intricate interplay between the reaction operation and the separation operation involved. The under-dampness can be substantially alleviated through the tight inventory control of bottom reboiler and this presents beneficial effects to process dynamics and operation. Two totally reboiled reactive distillation columns, separating, respectively, a hypothetical synthesis reaction from reactants A and B to product C, and a real decomposition reaction from 1, 4-butanediol to tetrahydrofuran and water, are employed to demonstrate these uncommon behaviors. The results obtained give full support to the above qualitative interpretation. Despite the strong influences of reaction kinetics and thermodynamic properties of the reacting mixtures, the totally reboiled reactive distillation columns are generally considered to present such unique behaviors and require tight inventory control of bottom reboiler to facilitate their control system development.

In this work, the impact of internal heat integration upon process dynamics and controllability by superposing reactive section onto stripping section, relocating feed locations, and redistributing catalyst within the reactive section is explored based on a hypothetical ideal reactive distillation system containing an exothermic reaction: A+B↔C+D. Steady state operation analysis and closed-loop controllability evaluation are carried out by comparing the process designs with and without the consideration of internal heat integration. For superposing reactive section onto stripping section, favorable effect is aroused due to its low sensitivities to the changes in operating condition. For ascending the lower feed stage, somewhat detrimental effect occurs because of the accompanied adverse internal heat integration and strong sensitivity to the changes in operating condition. For descending the upper feed stage, serious detrimental effect happens because of the introduced adverse internal heat integration and strong sensitivity to the changes in operating condition. For redistributing catalyst in the reactive section, fairly small negative influence is aroused by the sensitivity to the changes in operating condition. When reinforcing internal heat integration with a combinatorial use of these three strategies, the decent of the upper feed stage should be avoided in process development. Although the conclusions are derived based on the hypothetical ideal reactive distillation column studied, they are considered to be of general significance to the design and operation of other reactive distillation columns.