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Glass is a widely used material in key fields such as Micro-Electro-Mechanical Systems (MEMS) due to its excellent properties. The existing non-traditional glass machining methods have problems such as high pollution, difficult operation, and poor sustainability, this article utilizes the effective combination of electrochemical discharge machining and grinding (named electrochemical discharge grinding, ECDG), by using NaHCO 3 solution as electrolyte to achieve green machining. Utilizing ultrasonic vibration and multi-hole tube electrode to achieve precise and stable machining. Modeling and simulation analysis were conducted on the material removal rate and grinding force during the machining process, which profoundly revealed the joint improvement mechanism of spark discharge and ultrasonic vibration on grinding quality. First, a single factor experiment was used to preliminarily determine the machining threshold. Second, the Plackett-Burman experiment was used to screen key machining parameters. Then, Box-Behnken experiment was conducted on key machining parameters, and multi-objective and multi-factor optimization was performed to obtain the optimal combination of machining parameters. Compared with normal ECDG with cylindrical grinding electrode, the overcut is reduced by 8.3 %, the edge damage is reduced by 17.5 % and the surface roughness value is reduced by 70.6 %. Finally, by using the optimized combination of machining parameters, high-quality and stable machining of typical microchannel structures was achieved. The milling depth of the microchannel is 400 µm. The machining width is 1175 ± 5 µm. The surface roughness of the measurement area is 0.375 µm. The green, high-quality and stable machining of micro glass micro components further demonstrates the potential application of this compound technology. [Display omitted] [ABSTRACT FROM AUTHOR]

Converting natural forests to managed ecosystems generally increases soil nitrous oxide (N 2 O) emission. However, the pattern and underlying mechanisms of N 2 O emissions after converting tropical forests to managed plantations remain elusive. Hence, a laboratory incubation study was investigated to determine soil N 2 O emissions of four land uses including forest, eucalyptus, rubber, and paddy field plantations in a tropical region of China. The effect of soil carbon (C) and nitrogen (N) fractions on soil N 2 O emissions and related functional genes was also estimated. We found that the conversion of natural forests to managed forests significantly decreased soil N 2 O emissions, but the conversion to paddy field had no effect. Soil N 2 O emissions were controlled by both nitrifying and denitrifying genes in tropical natural forest, but only by nitrifying genes in managed forests and by denitrifying genes in paddy field. Soil total N, extractable nitrate, particulate organic C (POC), and hydrolyzable ammonium N showed positive relationship with soil N 2 O emission. The easily oxidizable organic C (EOC), POC, and light fraction organic C (LFOC) had positive linear correlation with the abundance of AOA– amoA , AOB– amoA , nirK , and nirS genes. The ratios of dissolved organic C, EOC, POC, and LFOC to total N rather than soil C/N ratio control soil N 2 O emissions with a quadratic function relationship, and the local maximum values were 0.16, 0.22, 1.5, and 0.55, respectively. Our results provided a new evidence of the role of soil C and N fractions and their ratios in controlling soil N 2 O emissions and nitrifying and denitrifying genes in tropical soils. [Display omitted] • Converting natural forest to managed plantation decreased soil N 2 O emissions. • The higher particulate organic C and hydrolyzable ammonium N increased soil N 2 O emission. • Soil carbon and nitrogen fraction ratios are more accurate than the total ratios in predicting soil N 2 O emission. • Nitrifying genes dominated in managed forest ecosystems while denitrifying genes dominated in paddy soils. [ABSTRACT FROM AUTHOR]

Abstract In this article we study the Borel probability measures that can be associated to the time averaged observation of the process generated by the non-autonomous long-wave-short-wave resonance equations on infinite lattices, via the notion of generalized Banach limit. We establish that the generated process possesses a pullback- D attractor, and further prove that there exists a unique family of invariant Borel probability measures carried by the pullback attractor. [ABSTRACT FROM AUTHOR]

Abstract With the increasing demand for clean and renewable energy, high-energy and power-density energy storage devices with the environmental and sustainable merits are highly needed. Herein, a convenient and sustainable approach was developed to construct 3D porous multi-component composites. The 3D Fe/Fe 3 O 4 /carbon composites were successfully derived from daily-used wet wipes. Such composites exhibited superior cycling and rate performance when evaluated as anode materials for lithium ion batteries. A highly reversible capacity of 814.0 mA h g−1 at 180th cycle was delivered at the rate of 0.2 A g−1. Moreover, a high capacity of 648.1 mA h g−1 was retained after long-life cycling (435 cycles) at the high rate of 1.0 A g−1. The work provided a prospective guidance for developing eco-friendly, sustainable, high-performance electrode materials for electrochemical energy storage applications. [ABSTRACT FROM AUTHOR]

High standards and urgent demands have been proposed for electrode materials because of the increasing market of rapid electrical power supply systems. Pseudocapacitance could provide an effective way for the development of electrode materials with both high energy and power densities. 3D graphene/α-Fe 2 O 3 nanocrystal composites have been inspired by the combination of facet engineering and composite construction. The materials are evaluated as anode materials for secondary lithium ion batteries. Compared with the pristine α-Fe 2 O 3 nanocrystal with oriented facet, the composites render evidently enhanced rate capability and long life span. Reversible capacities of 674 mA h g −1 (420 th cycle) and 336 mA h g −1 (750 th cycle) can be retained at relatively high rates of 1.0 A g −1 , and 5.0 A g −1 , respectively. Further investigations reveal that this outstanding performance is attributed to the enhanced pseudocapacitive contribution. The highly interconnected graphene matrix in the 3D composites provide fast electron transport pathways, and facilitate rapid ion diffusion, which eventually promote the pseudocapacitive lithium storage. The composite proves to be a promising candidate as a high-rate electrode material for lithium ion batteries. [ABSTRACT FROM AUTHOR]

The surface engineering strategy has exhibited unique advantages in photocatalysis, electrocatalysis, sensing, etc. Here in this work, NiO nano octahedron aggregates with exposure of active {111} facets are synthesized through a facile and scalable way. When evaluated as anode materials for Li ion batteries (LIBs), the NiO nano octahedron aggregates exhibit excellent rate performance and long-life cycling performance with high reversible capability. A reversible capability of as high as 793 mA h g −1 is retained after 200 cycles at 0.2C. Moreover, the excellent rate performance is achieved. The exceeding lithium storage performance is attributed to the synergy effect of nano size and exposed (111) surface of the NiO octahedra improving kinetics of charge transportation and Li ion diffusion. The NiO octahedron aggregates can be used as prospective host materials for investigation of surface effect on catalysis, sensing, switching, supercapacitors and electrodes for sodium batteries, fuel cells, etc. [ABSTRACT FROM AUTHOR]

• Attentional function altered in lowlanders at altitude after acute aerobic exercise. • Enhanced reactive control of attentional functions through physiological arousal. • Intensity and duration of exercise may affect the exercise-cognition interaction. Human attentional function is sensitive to hypoxia. However, little is known about whether and how attentional function is altered after acute aerobic exercise at high altitude, especially for acclimatized lowlanders. In this study, we used the Attention Network Test (ANT) to measure alerting, orienting, and executive control functions and the Stroop Color and Word Test (SCWT) with a different proportion of incongruent trials to investigate proactive and reactive control of executive function. We randomly divided the sample of 160 Tibetan lowlanders who had lived in the highlands for more than two years into four groups. Each of three groups performed 20 min of low-, moderate-, or high-intensity acute aerobic exercise, separately, and a control group watched a 20-min documentary. The ANT and SCWT were conducted before and after exercise or watching the documentary. The results indicated that the executive control effects of the three experimental groups significantly decreased and, in the posttest, the executive control effects of the high-intensity group were lower than those of the low-intensity group. Furthermore, the accuracy of the moderate- and high-intensity groups was increased significantly in the blocks containing 25% incongruent trials of SCWT task. These results suggest that the acute aerobic exercise at high altitude will improve the reactive control of attentional functions in acclimatized lowlanders, and the intensity may play an important role in the exercise-cognition interaction at high altitude. [ABSTRACT FROM AUTHOR]

A hierarchically photocatalytic microbial fuel cell system (PMFC) coupled with TiO 2 photoanode and bioanode was established to enhance the power generation based on single-chamber MFC. Compared with the conventional anaerobic mode, oxygen in the solution could be utilized by the photoanode of PMFC to improve the removal of o-chlorophenol (2-CP). The maximum power densities were increasing from 261 (MFC) to 301 mW/m2 (PMFC). The removal efficiency of 2-CP (5 mg/L) in PMFC was 76.20% and higher than that in MFC (19.33%) and by photocatalysis (49.23%). The electron-hole separation efficiencies were decreasing with the increasing of dissolved oxygen, causing a low efficiency of photocatalysis, due to the reduction of the current density of the systems. The abundance of Geobacter sp., PHOS-HE36 fam., and Pseudomonas sp. was increased with illumination, contributing to improve the electricity production and 2-CP degradation. The only detective intermediate of 1,2-dichlorobenzene in PMFC indicated that the microbes could regulate the degradation pathway of 2-CP in the coupling system. These findings provided an feasible method for the effective degradation of refractory organic compounds and simultaneous energy recovery by combining photocatalysis and microbial power generation. [Display omitted] • A photocatalysis and MFC coupled system, utilizing dissolved oxygen, was established. • There was a synergistic effect between photocatalysis and bioelectrochemistry. • The abundance of PHOS-HE36 fam. and Pseudomonas sp. was enhanced with illumination. • The behavior of microbes regulated the degradation pathways of the coupled system. [ABSTRACT FROM AUTHOR]

MnCeOx/NF, Co/MnCeOx/NF and HMoP/Co/MnCeOx/NF catalysts were optimized step by step and used for the selective catalytic reduction (SCR) of NOx with NH 3. The catalytic performance, water/sulfur resistances and N 2 selectivity of the overall catalyst were significantly improved and maintained during above continuous optimization processes. Firstly, MnCeOx loaded 3D monolithic Ni-foam (MnCeOx/NF) catalysts were investigated using response surface methodology (RSM) method with central composite design (CCD). Regression equations and 3D response surface graphs showed that the model-predicted value was highly in line with experiment-actual result for the catalytic performances synchronously corresponding to load and calcination temperature, calcination and reaction temperature, which obtained 95.7% NOx conversion with 76.7% N 2 -selectivity at 179.5 °C over the optimal 16.5%MnCeOx/NF catalyst calcinated at 432 °C. Calcination temperature has a great influence on SCR activity that a suitable one increased the surface Mn4+, Ce3+ and chemical adsorption oxygen, while a high one visibly decreased NOx conversion due to the rapid weakened oxygen absorption and lattice oxygen content. The coexistence of typical Eley–Rideal and Fast -SCR reaction mechanisms were found over MnCeOx/NF, while the reaction rate of intermediates changed significantly but also reduced N 2 -selectivity due to the increased rate of side reactions as reaction temperature increasing. Secondly, among Co-, Ni- or Fe-modified catalysts, the optimized Co/MnCeOx/NF obtain an acceptable H 2 O and SO 2 resistance with stable NOx conversion above 72% within 10 h at 175 °C. Furthermore, phosphomolybdic acid modified Co/MnCeOx/NF catalyst maintained more than 80% N 2 -selectivity at 275 °C along with almost 100% NOx conversion within 175 °C–275 °C. These advantages synergistically accelerate the overall SCR performances of activity, selectivity and resistance of the optimized HMoP/Co/MnCeOx/NF catalyst. MnCeOx/NF (monolithic nickel foam) catalyst was optimized by response surface methodology (RSM) method using central composite design (CCD), and further improved the resistances to H 2 O and SO 2 by Co-doping and enhanced N 2 -selectivity by phosphomolybdic acid (HMoP) modification. [Display omitted] • Novel RSM method using CCD was adopted to analyse catalytic performances. • Model-predicted values was highly in line with the experiment-actual results. • Typical Eley–Rideal and Fast -SCR mechanisms coexisted on MnCeOx/NF surface. • HMoP greatly improved the capacities of medium-temperature redox and NH 3 adsorption. • Strong electron interaction with abundant adsorbed-oxygen resulted in good activity. [ABSTRACT FROM AUTHOR]

The instability and high resistance of metallic Na/solid-state electrolyte (especially oxide-based electrolyte) interface are still challenges for all-solid-state sodium batteries. Herein, we propose a grain-boundary engineering strategy to stabilize the Na/Na 3 Zr 2 Si 2 PO 12 interface and improve the capability of sodium ion transfer at the interface. The chemical composition at the grain boundary of Na 3 Zr 2 Si 2 PO 12 is mediated via the addition of sintering additive Na 2 B 4 O 7 to facilitate the densification sintering at relatively low temperature and boost sodium ion migration across the grain boundary. Na 3 Zr 2 Si 2 PO 12 -10 wt% Na 2 B 4 O 7 demonstrates an optimized conductivity of 1.72 mS cm−1 at room temperature and the corresponding symmetric sodium cells exhibit ultra-stable sodium plating/stripping cycling under a current density of 0.3 mA cm−2 for over 2500 h at room temperature. Analysis reveals that a kinetically stable interphase forms between electrolyte and metallic Na, reducing the interfacial resistance from 90 Ω cm2 for Na 3 Zr 2 Si 2 PO 12 to 36 Ω cm2 for Na 3 Zr 2 Si 2 PO 12 -10 wt% Na 2 B 4 O 7. Cycling at stepwise changing temperature reconfirms the super stability of Na/Na 3 Zr 2 Si 2 PO 12 -10 wt% Na 2 B 4 O 7 interface. All solid-state batteries based on the Na 3 Zr 2 Si 2 PO 12 -10 wt% Na 2 B 4 O 7 demonstrates excellent cycling performance for over 200 cycles with limited capacity degradation. Our findings here open up a fertile avenue of exploration for all-solid-state sodium batteries utilizing NASICON-type electrolytes. [Display omitted] We put forward a grain boundary engineering strategy to regulate the grain boundary composition of Na 3 Zr 2 Si 2 PO 12 ceramic electrolytes and enhance the compatibility between metallic Na anode and Na 3 Zr 2 Si 2 PO 12. All solid-state sodium batteries based on the engineered electrolyte demonstrate superior cycling stability for over 200 cycles with limited capacity degradation. • We put forward a grain boundary engineering strategy to regulate grain boundary composition of electrolyte. • A kinetically stable interphase was formed between Na and ceramic electrolyte. • All solid-state sodium metal batteries are constructed. [ABSTRACT FROM AUTHOR]

Minban (“people-managed”) schooling was used as a very important instrument to deliver educational and political values in China in Mao''s era. Originating in the Yan''an Period in the middle 1940s, minban education experienced radicalized and hyperpoliticized development during the Great Leap Forward in 1958 and the Cultural Revolution during 1966–1976. In the reform era since 1979, since China''s national development policies required education to target educational quality and economic modernization, the Chinese government planned to eliminate minban schools and minban teachers by the year 2000. The elimination of minban schools was achieved easily through closing and merging schools. However, the minban-teacher elimination policies, including differentiating minban teachers'' payroll, admitting a very small proportion of them into the public teacher force and dismissing the majority, have created a variety of problems in rural basic education expansion. The elimination of minban teachers has been a drawn out and painstaking process, which continues into the new millennium. [Copyright &y& Elsevier]

• miR-194-5p inhibited the growth of pancreatic cancer by down-regulating PD-L1. • Restoring of miR-194-5p promoted the infiltration of CD8+ T cells into tumor tissues. • miR-194-5p promoted the secretion of IFN-γ of CD8+ T cells in pancreatic cancer. • miR-194-5p enhanced anti-tumor immunity in pancreatic cancer. • miR-194-5p may serve as a therapeutic target for pancreatic cancer. Pancreatic cancer is a highly malignant cancer of the digestive tract. Studies have shown that in some types of cancer, a high level of microRNA-194-5p (miR-194-5p) is beneficial for controlling tumor progression, while in other cancers it plays a completely opposite role. However, how miR-194-5p affects anti-tumor immunity of pancreatic cancer remains unclear. In this study, we found that high expression of miR-194-5p in human pancreatic cancer patients is associated with a better survival rate, while increased expression of programmed cell death ligand 1 (PD-L1) in human pancreatic cancer patients is associated with a worse survival rate. In pancreatic cancer, the expression level of PD-L1 is negatively correlated with the expression level of miR-194-5p, and we identified that PD-L1 was target gene of miR-194-5p. In addition, we found that overexpression of miR-194-5p inhibited the migration, invasion and proliferation of pancreatic cancer cells in vitro. The orthotopic mouse model of pancreatic cancer shown that miR-194-5p suppressed the progression of pancreatic cancer, promoted the infiltration of CD8+ T cells in tumor immune microenvironments, and enhanced the IFN-γ production of CD8+ T cells. Consistently, the co-culture experiments showed that overexpression of miR-194-5p in tumor cell enhanced IFN-γ production by CD8+ T cells. In conclusion, miR-194-5p may serve as a novel immunotherapeutic target for pancreatic ductal adenocarcinoma (PDAC) by inhibiting the expression of PD-L1, and play important roles in inhibiting the progression of pancreatic cancer and boosting the anti-tumor effect of CD8+ T cells. [ABSTRACT FROM AUTHOR]

• Ce-modified Mn-Fe catalysts showed higher SCR performance and SO 2 tolerance. • Good SCR activity might be attributed to more (Mn3++Mn4+) and Fe3+. • NO and NH 3 could be adsorbed on the catalyst surface in different forms. • The SCR reaction route mainly followed the Eley-Rideal mechanism. A series of metals doped Mn-Me-M x (Me = Fe, Cu, Ce; M x = Ce, Mg, Co, Ni, W) catalyst were synthesized by a co-precipitation method for low-temperature selective catalytic reduction of NO x with NH 3. The results showed that among the binary oxides catalysts, the Mn-Fe catalyst exhibited the best low-temperature activity, and more than 80 % NO x conversion in a reaction temperature range of 150−200 °C. and the ternary oxide catalysts Mn-Fe-Ce (0.1) prepared on this basis can reach about 95 % NO x conversion and excellent the tolerance of SO 2 and H 2 O at the same condition. The activity test results indicate that Ce-modification has a clear promoting effects on low temperature activity and resistance to SO 2 and/or H 2 O of the Mn-Fe catalyst. The effect of element doping on physiochemical properties of catalyst were investigated by XRD, BET, XPS, NH 3 -TPD and H 2 -TPR. The results show that there is a strong interaction between Ce, Co or Ni and Mn, Fe oxides, resulting in high dispersibility and reduced crystallinity of these oxides. In addition, the results always prove doping Ce could not only prominently modify and optimize the structure of mixed metal oxides, but also increase the relative content of Mn4+, Mn3+, Fe3+ and surface oxygen (O α) of Mn-Fe catalyst. Moreover, The specific surface area of the catalyst was increased and its surface acidity was strengthened after Ce doping, which is beneficial to increase the adsorption of NH 3. Finally, The typical Eley-Rideal mechanism over Mn-Fe-Ce (0.1) were proposed via the in situ DRIFTs experiments. [ABSTRACT FROM AUTHOR]

In order to study the effects of nanostructure configurations on surface electrocatalytic activity, a facile way for the design of hollow Co 3 O 4 prisms with different configurations and sizes via controlling the reaction kinetics is developed. And their electrocatalytic performance is evaluated by a series of electrochemistry test. It reveals that open configuration for oxygen evolution reaction (OER) electrocatalysis possess conducive influence for charge transfer and oxygen desorption, endowing the optimal electrocatalytic activity. Accordingly, the optimal electrocatalytic activities of Co 3 O 4 is demonstrated by optimizing microstructure, which with a small overpotential of 358 mV at a current density of 10 mA cm−2 and a lower Tafel slope of 56 mV dec−1. Comparable performance against noble metal-based electrocatalysts has been achieved. Image 1 • Hollow Co 3 O 4 prisms with different configurations and sizes were synthesized. • Optimal OER activity was demonstrated by optimizing microstructure. • Comparable performance Vs noble metal-based catalysts were achieved. [ABSTRACT FROM AUTHOR]

The conductive polyurethane/polypyrrole/graphene (CPU/PPy/Gr) particle electrode was prepared by an in-situ oxidative polymerization method and used as particle electrodes to degrade levofloxacin (LEV) in a three-dimensional electrode reactor. The prepared CPU/PPy/Gr electrode was characterized systematically and the effects of initial pH, initial LEV concentration, aeration volume, voltage, and electrolyte concentration on the degradation efficiency were investigated. Results showed that more than 90% LEV was degraded and the energy consumption was 20.12 kWh/g LEV under conditions of pH 7, 6 V voltage, 2.0 L/min aeration volume, 20 mg/L initial LEV concentration, and 7 mM concentration of electrolyte (Na 2 SO 4). A possible electrochemical oxidation pathway of LEV by the CPU/PPy/Gr electrode was proposed. In addition, the biotoxicity of LEV and its oxidation products was calculated using ECOSAR (Ecological Structure Activity Relationships) program in EPISuite. Toxicity evaluation using luminescent bacteria showed that the toxicities of some intermediates were higher than the parent compound. But the toxicity of degradation processes for LEV was effective decreasing. A possible reactive mechanism in the three-dimensional reactor was also recommended. In brief, the prepared CPU/PPy/Gr particle electrode constitutes an insight into the promising practical application in the wastewater treatment. Image 1 • CPU/PPy/Gr 3D particle electrode was prepared by in-situ oxidative polymerization. • Hydroxyl radical played an important role in the degradation process of LEV. • The hybrid toxicity showed an initial increase and later decrease trend over time. • The overall toxicity of LEV degradation system was effectively reduced. [ABSTRACT FROM AUTHOR]

There is an ongoing search to develop techniques for measurement of rhodamine B (RhB), an organic pollutant widely applied in many fields and presenting a serious threat to human health. In this study, a miniature electrochemical system was constructed to sensitively analyze for RhB by integrating a carboxylated multi-walled carbon nanotube and ionic liquid modified pencil-graphite electrode (MWCNTs-COOH/IL/PGE), an Ag/AgCl electrode, and a platinum wire all into a pipette tip. One distinct feature of this system was the small samples volumes from milliliter to microliter size needed for the analysis, which is critical when only small amounts of sample are available. Another advantage was the disposability of MWCNTs-COOH/IL/PGE and the pipette tip, which facilitated a practical in-situ measurement. The synergistic coupling effect between MWCNTs-COOH and IL fostered a high electrocatalytic activity of the sensor for RhB. Under optimum conditions, the oxidation peak current was linear with the concentration of RhB in the range of 0.005–2.0 μΜ and 2.0–60.0 μΜ. The lowest detection limit was found to be 1.0 nM. This study resulted in the development of a novel platform for the micro and ultra-sensitive measurement of RhB and provided great potential to simplify real-time environmental monitoring. [ABSTRACT FROM AUTHOR]

• 10-ethylphenoxazine (EPA) is used as redox mediator in the lithium-oxygen battery. • EPA reduces the charging-discharging overpotential to a record low value of 0.3 V. • A high energy efficiency of 90.4% is achieved for the lithium-oxygen battery. • EPA promotes uniform Li plating/stripping and prevents the formation of dendrites. • Tailorable lithium-oxygen batteries with low overpotentials are also demonstrated. Rechargeable lithium-Oxygen batteries (LOBs) are attractive alternatives to lithium ion batteries due to their high theoretical energy density. However, a large charge-discharge overpotential is usually accompanied, which reduces the energy efficiency and the cycling life. Redox mediators can be introduced in LOBs to reduce the overpotential by effectively decomposing the discharged product, lithium peroxide. Here, we propose 10-ethylphenoxazine as an active additive in the electrolyte to reduce the overpotential to 0.3 V and increase the energy efficiency to 90.4%. The 10-ethylphenoxazine is believed to favor the formation of stable solid electrolyte interface layer on the lithium anode, which benefits the even accumulation of the Li+ on the anode surface to prevent the formation of dendrite and improve the stability of Li foil against the attack of soluble species in the electrolyte. In addition, by utilizing a self-supporting graphene aerogel as the cathode, the LOB can be tailored to different sizes and shapes. The tailorable LOB features the low charging-discharging overpotential of 0.3 V and can be stably cycled for 93 times. With its excellent tailorability and stable electrochemical performance, the current LOB holds a promising future to power portable electronic devices with individualized sizes and shapes. The lithium-oxygen battery with 10-ethylphenoxazine (LOB-EPA) as redox mediator reduces the over-potential to 0.3 V, and benefits the even accumulation of Li+ on the anode surface. Meanwhile, this LOB-EPA has tailorable function for wide applications. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel B–Si–Zr hybridized ceramicizable resin(BSZ-PR) was fabricated by chemical reaction of boric acid, zirconium hydroxyl-containing polyhedral oligomeric silsesquioxane(Zr-POSS) and phenolic. The incorporation of boric acid and Zr-POSS improved the thermal stability of the resin effectively, and the residual carbon rate increased to 72.63% at 800 °C under nitrogen atmosphere. The flexural strength of carbon fiber/BSZ-PR and high silica fiber/BSZ-PR composites were increased by 25.7% and 175.5%, and linear ablation rates were reduced by 37% and 44.75%, respectively. It was discovered that the ceramic structures such as SiO 2 , ZrO 2 and SiC can be formed at high temperatures as well as under extreme ablative conditions from both BSZ-PR and its fiber-reinforced composites, which may be the key to the improved thermal, ablative properties. [ABSTRACT FROM AUTHOR]

• Low-dimensional multi-oxides nanosheet were synthesized successfully by one-step synthesis. • Co-Mn-SnO 2 solid solution promoted the efficient electron interaction for catalysis. • Increased adsorbed oxygen, Mn3++Mn4+, Sn4+ and more acidity on Lewis acid sites were obtained. • E-R and l -H mechanisms co-existed on Co-Mn-SnO 2 surface in SCR reaction process. • L-NH 3 species and bidntate nitrate were the main active species at high temperatures. NH 3 -SCR performances were explored to the relationship between structure morphology and physio-chemical properties over low-dimensional ternary Mn-based catalysts prepared by one-step synthesis method. Due to its strong oxidation performance, Sn-MnOx was prone to side reactions between NO, NH 3 and O 2 , resulting in the generation of more NO 2 and N 2 O, here most of N 2 O was driven from the non-selective oxidation of NH 3 , while a small part generated from the side reaction between NH 3 and NO 2. Co or Ni doping into Sn-MnOx as solid solution components obviously stronged the electronic interaction for actively mobilization and weakened the oxidation performance for signally reducing the selective tendency of side reactions to N 2 O. The optimal modification resulted in improving the surface area and enhancing the strong interaction between polyvalent cations in Co/Ni-Mn-SnO 2 to provide more surface adsorbed oxygen, active sites of Mn3+ and Mn4+, high-content Sn4+ and plentiful Lewis-acidity for more active intermediates, which significantly broadened the activity window of Sn-MnOx, improved the N 2 selectivity by inhibiting N 2 O formation, and also contributed to an acceptable resistances to water and sulfur. At low reaction temperatures, the SCR reactions over three catalysts mainly obeyed the typical Elye-rideal (E-R) routs via the reactions of adsorbed l -NH x (x = 3, 2, 1) and B-NH 4 + with the gaseous NO to generate N 2 but also N 2 O by-products. Except for the above basic E-R reactions, as increasing the reaction temperature, the main adsorbed NO x -species were bidentate nitrates that were also active in the Langmuir-Hinshelwood reactions with adsorbed l -NH x species over Co/Ni modified Mn-SnO 2 catalyst. Probable surface SCR reaction pathways over Ni/Co-modified Mn-SnO 2 were put forward to follow the basic Elye-Rideal reactions between gaseous NO with adsorbed l -NH x on Lewis acid sites at low temperature while also obey the Langmuir-Hinshelwood routes of main active bidentate nitrates with l -NHx as increasing the reaction temperature. [Display omitted] [ABSTRACT FROM AUTHOR]

Arsenic is highly toxic and therefore represents a potential threat to the environment and human health. The mobility and fixation of arsenic in natural environment is significantly affected by co-occurring dissolved natural organic acids, which are widely present in soils and sediments due to the decomposition of natural organic matters and the metabolism of plant roots and microorganisms. It was reported recently that at lower pH, citrate decreased arsenate adsorption on metal oxides as the result of competitive adsorption. This study examined the relationship between citrate-promoted goethite dissolution and citrate-suppressed arsenate adsorption in the equilibrated goethite–arsenate–citrate systems with different contact orders. The results indicated that there is obvious correlation between the suppression of arsenate adsorption and dissolution of goethite. Arsenate adsorption and goethite dissolution in the presence of citrate (1.0mM), oxalate (1.5mM) and acetate (3.0mM) were compared. The results showed that arsenate adsorption was most significantly inhibited by citrate among the three organic acids. Although oxalate dissolved goethite more significantly, it inhibited arsenate adsorption much less than citrate. Hence it is proposed that the competition for binding sites rather than citrate-promoted goethite dissolution played a key role in the reduction of arsenate adsorption by citrate at lower pH. [Copyright &y& Elsevier]