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In present study, a high-efficiency CaO–SiO 2 –Al 2 O 3 –MgO slag was designed to dissolve alumina particles, and the in situ observation for alumina particles dissolution by CSLM instrument equipped with color fast CCD camera was conducted, which broke through the limitations of the original CSLM equipment. The dynamic measurements showed that the dissolution behavior of alumina particles was controlled by diffusion. Moreover, the mechanism of dissolution of alumina particles was illustrated by combining SEM-EDS detection and thermodynamic calculations. It was found that there was an about 3 μm distinct interface layer when alumina particles were dissolved in slag, and the formation order of products of the interface layer was closely related to its thermodynamics. In addition, the apparent activation energy of reaction between Al 2 O 3 and CaO was used to calculate the reaction time of alumina particles with different particle size, and the viscosity values of the all slags obtained by the Factsage 8.2 thermodynamic software and Stocks-Einstein theory were used to calculate the time required for diffusion of alumina particles with different particle sizes. Compared the total time of chemical reaction and the diffusion mass transfer, it is found that when the radius of alumina particles is greater than 2.5 μm, the dissolutions of alumina particles in all CaO–SiO 2 –Al 2 O 3 –MgO slag composition points are controlled by diffusion. [ABSTRACT FROM AUTHOR]

The soil environment is an important factor that affects the growth of maize. Our study discusses the effect of carbon-based fertilizer on the rhizosphere soil microenvironment. Xianyu 335 and Jingke 968 maize varieties were selected, and six treatments were set up as follows: no fertilizer, chemical fertilizer, or carbon-based fertilizer (3 t/hm2, 3.75 t/hm2, 4.5 t/hm2, and 5.25 t/hm2). The results showed that the carbon-based fertilizer significantly reduced the soil pH value in the late growth stage. Carbon-based fertilizer can significantly improve the conductivity of soil solution. On 8 July (jointing stage), the conductivity of the two varieties of soil was the highest at 3.75 t treatment, 259.38% and 169.26% higher than that of chemical fertilizer, respectively. Carbon-based fertilizer significantly increased the soil carbon flux. The soil carbon flux of Jingke 968 showed a trend of first rising and then falling with the increase in the application amount of carbon-based fertilizer. On 8 July (jointing stage) and 28 July (tasseling stage), the 4.5 t treatment reached the maximum value, and on 16 August (early filling stage) and 4 September (waxy stage), the 3.75 t treatment reached the maximum value. Carbon-based fertilizer significantly increased the content of nitrate nitrogen, ammonium nitrogen, available phosphorus, and available potassium in the topsoil. Carbon-based fertilizer had a significant effect on soil enzyme activity and significantly increased soil neutral phosphatase activity in the late growth stage. On 16 August (early stage of grouting), β-Glucosidase activity was significantly higher in 3 t and 3.75 t treatments than other treatments in Xianyu 335 and Jingke 968. The activity of α-Xylosidase reached the highest at 3.75 t. The activities of polyphenol oxidase and catalase reached their maximum at 5.25 t treatment on 4 September (waxy ripening) and 26 September (full ripening). Carbon-based fertilizer significantly increased the soil bacterial diversity index (Shannon index, ACE index and Chao1 index), but had no significant impact on the fungal diversity index, and significantly increased the abundance of soil bacterial and fungal populations. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) is the largest grain crop in Heilongjiang Province. Carbon-based fertilizer is a mixed fertilizer produced by adding a certain proportion of chemical fertilizer with biochar as the loading substrate. In this study, the effects of carbon-based fertilizer on the rhizosphere soil microenvironment and maize root system were discussed. Two maize varieties, Xianyu 335 and Jingke 968, were selected and six treatments were set as follows, including no fertilization (CK1), conventional fertilizer (CK2) and the amount of carbon-based fertilizer, which were 3 t/hm2, 3.75 t/hm2, 4.5 t/hm2 and 5.25 t/hm2, respectively. The results showed that carbon-based fertilizer increased the total root length, root volume, root area and root tip number of maize, and the root length, root volume, root area and root tip number of 4.5 t treatment performed better at all stages, which was significantly higher than that of chemical fertilizer. On 16 August (early filling stage), most of the root color changed from milky white to dark brown, the root clarity decreased, the number of roots decreased, the root volume significantly decreased and the root began to age, while the number and volume of roots treated with the carbon-based fertilizer remained stable, the root color was milky white, the morphological structure was clear and there was basically no aging. The carbon-based fertilizer treatment significantly increased the root biomass of 0–15 cm above the plant, 15–30 cm and 30–45 cm between the plants and 0–15 cm between the ridges, forming a wide and deep high-yield root system. The carbon-based fertilizer significantly increased the bleeding rate. On 8 July (jointing stage), Xianyu 335 and Jingke 968 reached the maximum value at the 3 t and 3.75 t treatments, respectively. The carbon-based fertilizer treatment had no significant effect on the amino acid content, but significantly increased the amino acid transport rate on 8 July (jointing stage) and 16 August (early filling stage). The transport rate of inorganic phosphorus gradually decreased with the advancement of the growth process. On 8 July (jointing stage), the ammonium nitrogen content and transport rate of the two varieties reached the maximum value at the treatment of 4.5 t and 3.75 t, which was significantly higher than the treatment of chemical fertilizer and no fertilizer, and showed a gradual downward trend with the advancement of the growth process. The soluble sugar content was relatively low in the early stage and increased rapidly on 4 September (waxy ripening stage). Both varieties reached the maximum value at 4.5 t treatment, and the transport rate reached the maximum value at 3.75 t treatment, which was significantly higher than that of the chemical fertilizer treatment. In conclusion, the carbon-based fertilizer significantly increased the yield of maize, and the yield of maize under the 4.5 t treatment reached the maximum, which was 15.02% and 18.24% higher than that of the chemical fertilizer treatment, respectively. [ABSTRACT FROM AUTHOR]

Long-term application of mineral fertilizers might have adverse effects on soil quality and crop yield, which can be alleviated by biochar-based organic fertilizer (BOF) amendment that has been considered a potential strategy for improving soil quality and crop yields. Therefore, this study was conducted to explore the effects of partial substitution of mineral fertilizer with BOF on the yield and sugar content of sugar beet and to investigate whether such effects are correlated with the changes in photosynthesis, nitrogen assimilation, and sucrose synthesis. Five treatments, including one mineral fertilizer (CK) and four different application rates of BOF + inorganic nitrogen fertilizer, assigned as (B1), (B2), (B3), and (B4) treatments, were used. The total N, P2O5, and K2O contents for each treatment were equal, and their deficiency in the converter was overcome by mineral fertilizers. Compared with BOF, mineral fertilizer promoted sugar beet growth at 60 days after sowing (DAS). After 85 DAS, however, BOF enhanced photosynthetic pigment synthesis and photosystem II (PSII) activity, caused the delayed leaf senescence, and increased the amount of nitrogen assimilated and the capacity for sucrose synthesis in sugar beet leaves. Moreover, the B4 treatment significantly increased the soil nitrate-nitrogen content at the 100–200 cm soil depth and also the risk of leaching. The recommended optimal fertilization treatment was 3.25 t ha–1 BOFs + 50 kg ha–1 N + 25 kg ha–1 P2O5 + 25 kg ha–1 K2O (the B3 treatment). [ABSTRACT FROM AUTHOR]

A coupled bio-chemo-hydro-mechanical model (BCHM) is developed to investigate the permeability reduction and stiffness improvement in soil by microbially induced calcite precipitation (MICP). Specifically, in our model based on the geometric method a link between the micro- and macroscopic features is generated. This allows the model to capture the macroscopic material property changes caused by variations in the microstructure during MICP. The developed model was calibrated and validated with the experimental data from different literature sources. Besides, the model was applied in a scenario simulation to predict the hydro-mechanical response of MICP-soil under continuous biochemical, hydraulic and mechanical treatments. Our modelling study indicates that for a reasonable prediction of the permeability reduction and stiffness improvement by MICP in both space and time, the coupled BCHM processes and the influences from the microstructural aspects should be considered. Due to its capability to capture the dynamic BCHM interactions in flexible settings, this model could potentially be adopted as a designing tool for real MICP applications. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) is the most important food crop in the world, with significant acreage and production across the globe. However, it is affected by low temperatures throughout its growth process, especially during germination. Therefore, it is important to identify more QTLs or genes associated with germination under low-temperature conditions. For the QTL analysis of traits related to low-temperature germination, we used a high-res genetic map of 213 lines of the intermated B73 × Mo17 (IBM) Syn10 doubled haploid (DH) population, which had 6618 bin markers. We detected 28 QTLs of eight phenotypic characteristics associated with low-temperature germination, while they explained the phenotypic contribution rate of 5.4 ~ 13.34%. Additionally, 14 overlapping QTLs produced six QTL clusters on every chromosome, except for 8 and 10. RNA-Seq found six genes related to low-temperature tolerance in these QTLs, while qRT-PCR analysis demonstrated that the expression trends of the Zm00001d045568 gene in the LT_BvsLT_M group and the CK_BvsCK_M group were highly significantly different at all four-time points (P < 0.01), and encoded the RING zinc finger protein. It was located on qRTL9-2 and qRSVI9-1 and is related to the total length and simple vitality index. These results provided potential candidate genes for further gene cloning and improving the low-temperature tolerance of maize. [ABSTRACT FROM AUTHOR]

Zeolite membranes are highly attractive in energy efficient, selective separation technologies. Their high selectivity originates from selective adsorption, diffusion and even molecular sieving. High flux zeolite membranes (> 1 mol s−1m−2) with a sub‐micrometer thickness are mechanically stabilized by a porous, often multilayer, support. Transport mechanisms in zeolite layer and support, however, are counteracting regarding selectivity, and a support may also act as a flux resistance. Several examples are analyzed quantifying the impact of the support on the observed performance, showing the effect of layer thickness, orientation of the asymmetric membrane and operational conditions, resulting in recommendations for the configuration of zeolite membrane modules. [ABSTRACT FROM AUTHOR]

Capture and storage of the long‐lived 85Kr is an efficient approach to mitigate the emission of volatile radionuclides from the spent nuclear fuel reprocessing facilities. However, it is challenging to separate krypton (Kr) from xenon (Xe) because of the chemical inertness and similar physical properties. Herein we prepared high‐silica CHA zeolite membranes with ultra‐high selectivity and irradiation stability for Kr/Xe separation. The suitable aperture size and rigid framework endures the membrane a strong size‐exclusion effect. The ultrahigh selectivity of 51–152 together with the Kr permeance of 0.7–1.3×10−8 mol m−2 s−1 Pa−1 of high‐silica CHA zeolite membranes far surpass the state‐of‐the‐art polymeric membranes. The membrane is among the most stable polycrystalline membranes for separation of humid Kr/Xe mixtures. Together with the excellent irradiation stability, high‐silica CHA zeolite membranes pave the way to separate radioactive Kr from Xe for a notable reduction of the volatile nuclear waste storage volume. [ABSTRACT FROM AUTHOR]

Capture and storage of the long‐lived 85Kr is an efficient approach to mitigate the emission of volatile radionuclides from the spent nuclear fuel reprocessing facilities. However, it is challenging to separate krypton (Kr) from xenon (Xe) because of the chemical inertness and similar physical properties. Herein we prepared high‐silica CHA zeolite membranes with ultra‐high selectivity and irradiation stability for Kr/Xe separation. The suitable aperture size and rigid framework endures the membrane a strong size‐exclusion effect. The ultrahigh selectivity of 51–152 together with the Kr permeance of 0.7–1.3×10−8 mol m−2 s−1 Pa−1 of high‐silica CHA zeolite membranes far surpass the state‐of‐the‐art polymeric membranes. The membrane is among the most stable polycrystalline membranes for separation of humid Kr/Xe mixtures. Together with the excellent irradiation stability, high‐silica CHA zeolite membranes pave the way to separate radioactive Kr from Xe for a notable reduction of the volatile nuclear waste storage volume. [ABSTRACT FROM AUTHOR]

Subsea Mudlift Drilling is a newly developed technology that provides a good solution to the problem of narrow pressure window in deep-water areas. However, current researches on Subsea Mudlift Drilling seldom focus on hydrate formation in a wellbore. Considering the shortcomings of current researches, a heat transfer model is established in this paper considering the specific flow path during Subsea Mudlift Drilling. A numerical model for the pressure profile during Subsea Mudlift Drilling is also established considering the lift force by the subsea pump. On basis of these models, a prediction method for the hydrate formation region is proposed, combining the hydrate phase equilibrium equation. In addition, a series of numerical simulations are conducted, which indicate that hydrate is easier to form during Subsea Mudlift Drilling than during conventional drilling. In order to reduce the hydrate formation region, a smaller head for the subsea pump, smaller diameter of the return line, larger displacement of the drilling fluid, and higher concentrations of inhibitors are suggested during Subsea Mudlift Drilling. On the basis of the numerical simulation results, an optimization method of hydraulic parameters for Subsea Mudlift Drilling is proposed. Conclusions and suggestions in this paper can help engineers to reduce hydrate formation during subsea Mudlift Drilling. [ABSTRACT FROM AUTHOR]

In order to further expand the flight envelope of quadrotors under actuator failures, we design a nonlinear sensor-based fault-tolerant controller to stabilize a quadrotor with failure of two opposing rotors in the high-speed flight condition (>8 m/s). The incremental nonlinear dynamic inversion approach which excels in handling model uncertainties is adopted to compensate for the significant unknown aerodynamic effects. The internal dynamics of such an underactuated system have been analyzed, and subsequently stabilized by redefining the control output. The proposed method can be generalized to control a quadrotor under single-rotor-failure and nominal conditions. For validation, flight tests have been carried out in a large-scale open jet wind tunnel. The position of a damaged quadrotor can be controlled in the presence of significant wind disturbances. A linear quadratic regulator approach from the literature has been compared to demonstrate the advantages of the proposed nonlinear method in the windy and high-speed flight condition. [ABSTRACT FROM AUTHOR]

• Experimental and numerical investigations are carried out to analyze the cement hydration in different temperature. • Coupled heat and mass transfer model between cement and hydrate layer is proposed. • Numerical study on multi-field coupling mechanisms between cement and hydrate layer is conducted. Exploitation of natural gas hydrates from horizontal wells can significantly improve the production rate and final recovery. However, the long interaction surfaces of horizontal wells may easily disturb the hydrate reservoir. Cement hydration in wellbore is an exothermic reaction, which may lead to the premature dissociation of hydrate, thereby threatening the wellbore integrity. In the present study, experimental and numerical investigations are carried out to analyze the cement hydration in a wide range of temperatures. Then, a coupled model is established considering the multi-field coupling mechanisms between horizontal wells and the hydrate reservoir during well cementing. In the proposed model, the cement hydration, phase change of hydrate, and the multiphase flow in porous hydrate layer are considered. The cement hydration process, transient temperature and pressure distributions, and the hydrate phase change are analyzed by numerical simulations. Results show that the temperature of wellbore and hydrate increases rapidly. The saturation of the hydrate layer within the region 3 times of wellbore diameter decreases significantly. The pressure at the wellbore-hydrate layer interface increases significantly, which may lead to gas penetration into the wellbore. Moreover, threats imposed by the premature dissociation of hydrate last even for a long period after well cementing. [ABSTRACT FROM AUTHOR]

The steep stepwise uptake of water vapor and easy release at low relative pressures and moderate temperatures together with high working capacities make metal-organic frameworks (MOFs) attractive, promising materials for energy efficient applications in adsorption devices for humidity control (evaporation and condensation processes) and heat reallocation (heating and cooling) by utilizing water as benign sorptive and low-grade renewable or waste heat. Emerging MOF-based process applications covered are desiccation, heat pumps/chillers, water harvesting, air conditioning, and desalination. Governing parameters of the intrinsic sorption properties and stability under humid conditions and cyclic operation are identified. Transport of mass and heat in MOF structures, at least as important, is still an underexposed topic. Essential engineering elements of operation and implementation are presented. An update on stability of MOFs in water vapor and liquid systems is provided, and a suite of 18 MOFs are identified for selective use in heat pumps and chillers, while several can be used for air conditioning, water harvesting, and desalination. Most applications with MOFs are still in an exploratory state. An outlook is given for further R&D to realize these applications, providing essential kinetic parameters, performing smart engineering in the design of systems, and conceptual process designs to benchmark them against existing technologies. A concerted effort bridging chemistry, materials science, and engineering is required. [ABSTRACT FROM AUTHOR]

Xe is only produced by cryogenic distillation of air, and its availability is limited by the extremely low abundance. Therefore, Xe recovery after usage is the only way to guarantee sufficient supply and broad application. Herein we demonstrate DD3R zeolite as a benchmark membrane material for CO2/Xe separation. The CO2 permeance after an optimized membrane synthesis is one order magnitude higher than for conventional membranes and is less susceptible to water vapour. The overall membrane performance is dominated by diffusivity selectivity of CO2 over Xe in DD3R zeolite membranes, whereby rigidity of the zeolite structure plays a key role. For relevant anaesthetic composition (<5 % CO2) and condition (humid), CO2 permeance and CO2/Xe selectivity stabilized at 2.0×10−8 mol m−2 s−1 Pa−1 and 67, respectively, during long‐term operation (>320 h). This endows DD3R zeolite membranes great potential for on‐stream CO2 removal from the Xe‐based closed‐circuit anesthesia system. The large cost reduction of up to 4 orders of magnitude by membrane Xe‐recycling (>99+%) allows the use of the precious Xe as anaesthetics gas a viable general option in surgery. [ABSTRACT FROM AUTHOR]

Xe is only produced by cryogenic distillation of air, and its availability is limited by the extremely low abundance. Therefore, Xe recovery after usage is the only way to guarantee sufficient supply and broad application. Herein we demonstrate DD3R zeolite as a benchmark membrane material for CO2/Xe separation. The CO2 permeance after an optimized membrane synthesis is one order magnitude higher than for conventional membranes and is less susceptible to water vapour. The overall membrane performance is dominated by diffusivity selectivity of CO2 over Xe in DD3R zeolite membranes, whereby rigidity of the zeolite structure plays a key role. For relevant anaesthetic composition (<5 % CO2) and condition (humid), CO2 permeance and CO2/Xe selectivity stabilized at 2.0×10−8 mol m−2 s−1 Pa−1 and 67, respectively, during long‐term operation (>320 h). This endows DD3R zeolite membranes great potential for on‐stream CO2 removal from the Xe‐based closed‐circuit anesthesia system. The large cost reduction of up to 4 orders of magnitude by membrane Xe‐recycling (>99+%) allows the use of the precious Xe as anaesthetics gas a viable general option in surgery. [ABSTRACT FROM AUTHOR]

A systematic approach is described for the fabrication of defect-free high-silica zeolite membranes with CHA (SSZ-13) topology. Home-made hydrothermally-synthesized CHA seeds were coated on porous α-alumina substrates with a pore diameter of 80 nm and by means of a further hydrothermal treatment a zeolite membrane layer was formed. In order to obtain a thin and defect-free zeolite layer, the influence on the final microstructure of seed concentration during coating, coating method (rubbing, dip- or spin-coating) and crystal growth time was investigated. The template removal procedure was optimized to avoid the formation of cracks or defects. For an optimal thermal treatment, using a step-wise temperature increase to 500 °C, the membranes exhibit CO 2 /CH 4 permselectivities of 25–30 with CO 2 permeances of around 2 x 10−7 mol m−2 s−1 Pa−1 at 22 °C and 2 bar of pressure difference. O 2 plasma pre-treatment prior to template removal increased the CO 2 /CH 4 permselectivity to 176, while maintaining the same CO 2 permeance values when no pre-treatment was used. The SF 6 permeances, both at low (22 °C) and high (200 °C) temperatures, were below the detection limit (2 x 10−10 mol m−2 s−1 Pa−1), which in return results in very high N 2 /SF 6 permselectivities of more than 700. • High-silica (SSZ-13) CHA zeolite membranes were fabricated by hydrothermal synthesis. • The optimized template removal method avoids the formation of defects. • Oxygen plasma, used as a pre-treatment, improves CO 2 /CH 4 permselectivity by 570%. • The membranes exhibit very high N 2 /SF 6 permselectivities of more than 700. [ABSTRACT FROM AUTHOR]

Catalytic hydrogenation presents a promising approach for converting CO2 into valuable chemicals and fuels, crucial for climate change mitigation. Iron-based catalysts have emerged as key contributors, particularly in driving the reverse water–gas shift and Fischer–Tropsch synthesis reactions. Recent research has focused on enhancing the efficiency and selectivity of these catalysts by incorporating alkali metal promoters or transition metal dopants, enabling precise adjustments to their composition and properties. This review synthesizes recent theoretical advancements in CO2 hydrogenation with iron-based catalysts, employing density functional theory and microkinetic modeling. By elucidating the underlying mechanisms involving metallic iron, iron oxides, and iron carbides, we address current challenges and provide insights for future sustainable CO2 hydrogenation developments. [ABSTRACT FROM AUTHOR]

Abstract Well cementing aids in enhancing wellbore stability and provides zonal isolation during the exploration of oil, gas, and hydrate energy. However, cementing a well through hydrate layer is problematic. The heat generation from cement hydration leads to the dissociation of the hydrate around the wellbore, resulting in cementing operation failure or serious safety accidents. Current studies seldom focused on the stability of the hydrate layer during well cementing. Therefore, a transient thermal model of cement column is established in this study on the basis of cement hydration kinetics model. On this foundation, a coupled model between the cement column and hydrate layer is established given the interactions between temperature field, hydrate layer, and cement hydration reaction. The transient thermal model of cement column is verified through a field test and the thermal model of hydrate layer is verified by an experiment, which exhibit good agreement. Based on the simulation results conducted in this paper, the total heat generation during cement hydration reaches 198,247 kJ/m, which leads to the dissociation of 9.84 × 10 4 k g hydrate. The hydrate dissociation is a significantly longer process when compared with the cement hydration process. Thus, the safety threats posed by hydrate dissociation exist during well cementing and also for a long time after well cementing. Additionally, the results suggest that the use of a casing with a higher diameter significantly reduces the hydrate dissociation. The conclusions and suggestions of the study can aid in troubleshooting problems and optimizing the cement operation in the hydrate layer. Highlights • Heat generation is quantitatively described based on cement kinetics model. • Thermal model of hydrate layer considering cement hydration heat is proposed. • A case study is conducted to study hydrate layer stability during well cementing. [ABSTRACT FROM AUTHOR]

Abstract This paper proposes an Incremental Sliding Mode Control driven by Sliding Mode Disturbance Observers (INDI-SMC/SMDO), with application to a quadrotor fault tolerant control problem. By designing the SMC/SMDO based on the control structure of the sensor-based Incremental Nonlinear Dynamic Inversion (INDI), instead of the model-based Nonlinear Dynamic Inversion (NDI) in the literature, the model dependency of the controller and the uncertainties in the closed-loop system are simultaneously reduced. This allows INDI-SMC/SMDO to passively resist a wider variety of faults and external disturbances using continuous control inputs with lower control and observer gains. When applied to a quadrotor, both numerical simulations and real-world flight tests demonstrate that INDI based SMC/SMDO has better performance and robustness over NDI based SMC/SMDO, in the presence of model uncertainties, wind disturbances, and sudden actuator faults. Moreover, the implementation process is simplified because of the reduced model dependency and smaller uncertainty variations of INDI-SMC/SMDO. Therefore, the proposed control method can be easily implemented to improve the performance and survivability of quadrotors in real life. [ABSTRACT FROM AUTHOR]

Ultrathin mixed matrix membranes (MMMs) containing two-dimensional (2D) fillers are highly sought recently due to their good performance in gas separations. Here we report the preparation of PIM-1 based ultrathin MMMs containing 2D metal-organic framework (MOF) nanosheets using spin coating method. The lamellar structure of the 2D layered MOF filler (copper 1,4-benzenedicarboxylate nanosheets, CuBDC-ns) enlarges the contacting area between fillers and the polymer matrix, leading to the formation of dense MMMs. The centrifugal force generated during the spin coating process helps to horizontally align these CuBDC-ns, increasing the gas diffusion resistance across the membrane. The influence of membrane thickness and filler content on the separation performance of CO 2 /CH 4 mixture is examined and discussed. Optimizing membrane thickness and filler content results in a 660 nm thick ultrathin MMM comprising 10 wt% CuBDC-ns, which exhibits a CO 2 /CH 4 selectivity of 15.6 and CO 2 permeance as high as 407 GPU, surpassing other PIM-1 based membranes. Besides, the long term stability test shows that the prepared ultrathin MMMs are stable up to 100 h. These results demonstrate that the ultrathin MMMs reported in this study are excellent candidates for CO 2 /CH 4 separation, with potential applications in natural gas purification and biogas upgrading. [ABSTRACT FROM AUTHOR]

CHA zeolite membranes have been successfully synthesized on thin yttria-stabilized zirconia (YSZ) hollow fiber (HF) substrates by secondary growth method. Prior to membrane synthesis, the outer surface of YSZ hollow fibers were planted with ball-milled submicron CHA zeolite seeds. Extensive investigations on batch-scale preparation of CHA zeolite membranes were carried out in terms of seeding method. Uniform and continuous seed layers were achieved by vacuum seeding with the addition of colloidal silica in seed suspension, which resulted in high reproducibility HF CHA zeolite membranes at crystallization temperature of 160 °C for 20 h. The membranes showed average water permeation flux of ca. 8.0 kg m −2 h −1 with separation factor of ca. 2500 in 90 wt% ethanol/water mixture at 75 °C. A HF CHA zeolite membrane module was fabricated for multi-cycle dehydration of iso-propanol/water mixture and acetic acid/isopropanol/water mixtures at 75 °C with high stability for over 100 h. [ABSTRACT FROM AUTHOR]

Saline–alkaline (SA) soil inhibits plant growth and development. A few plants have evolved strategies to combat SA stress, but the underlying mechanisms remain elusive. In the current study, we performed a combined proteome and metabolome profiling to capture the major pathways and specified metabolites involved in the sugar beet tolerance to SA stress. Protein abundance and metabolite accumulation in purine metabolism were altered to favour allantoin accumulation under SA stress. Exogenous allantoin alleviated the oxidative damage caused by SA stress, whereas inhibition of allantoin biosynthesis weakened SA tolerance. Transcriptome analysis revealed that allantoin altered the expression patterns of genes involved in jasmonic acid (JA) and nitric oxide (NO) biosynthesis to elevate their levels under SA stress. Inhibition of allantoin biosynthesis completely abolished the JA and NO accumulation. The application of JA and NO promoted the accumulation of each other, and both enhanced SA tolerance. Inhibition of JA biosynthesis completely abolished allantoin-induced SA tolerance and NO accumulation and weakened sodium nitroprusside (SNP, a donor of NO) -induced SA tolerance, whereas inhibition of NO biosynthesis only attenuated allantoin-induced SA tolerance and JA accumulation and JA-induced SA tolerance. Our results suggest that allantoin accumulation is assisted under SA stress, promoting JA accumulation and consequently NO biosynthesis. Subsequently, NO in turn assists JA biosynthesis, forming a self-amplifying feedback loop, in which JA and NO synergistically improve SA tolerance. The current study provides a novel insight into SA tolerance in sugar beet and preliminary reveals the regulatory role of allantoin in SA tolerance. • Purine metabolism was a key pathway for saline–alkaline tolerance in sugar beet. • Saline–alkaline stress induced changes of purine metabolism in the direction favoring allantoin accumulation. • Allantoin promoted the biosynthesis of jasmonic acid and nitric oxide under saline–alkaline stress. • Jasmonic acid and nitric oxide synergistically enhanced the saline–alkaline tolerance of sugar beet. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three phenolic hydroxyl-functionalized hyper-cross-linked polymers were produced. • These polymers contained abundant phenolic –OH (up to 17.95 wt%), high S BET and V total. • The polymers were promising for adsorptive removal of aniline with the q max of 210.9 mg/g. • Acid-base interaction and hydrogen bonding, especially the micropore-filling were the main driving forces. Herein, three phenolic hydroxyl-functionalized hyper-cross-linked polymers were synthesized according to two sequential Friedel-Crafts alkylation reactions at two different temperatures and they were used to adsorb aniline. The first reaction at 293 K brought abundant phenolic –OH (up to 17.95 wt%) to the intermediates, and the followed reaction at 353 K offered the resultant products with a hyper-cross-linked frameworks composed of plentiful rigid methylene bridges. The resulting polymers were promising for the adsorption of aniline, and the maximum capacities (q max) arrived at 210.9 mg/g. As the initial concentration of aniline was<100 mg/L, the adsorption efficiency reached>95 %, and the final concentration was lower than 0.1 mg/L, much lower than the emission concentration limit of aniline in China (1.0 mg/L). The adsorption mechanism discovered that acid-base interaction, electrostatic interaction and hydrogen bonding, especially the micropore-filling were important for the adsorption. [ABSTRACT FROM AUTHOR]

Stable and accurate prediction of crude oil prices is critical to national security, economic development, and even international relations, against the background of the COVID-19 and Russia–Ukraine war. Therefore, a memory-based hybrid forecasting system is established for point prediction and interval prediction of crude oil prices in this research, which more thoroughly separates the noise in the raw data and achieves superior prediction performance. There are five main steps in the proposed model: decomposing the raw data into intrinsic mode functions (IMFs) through our new data preprocessing technique complete ensemble extreme-point symmetric mode decomposition with adaptive noise (CEESMDAN), ensemble of IMFs based on memory features, prediction of reconstructed components, error correction via grey wolf optimizer (GWO) for final point prediction, obtaining interval prediction by multi-objective grey wolf optimizer (MOGWO). The empirical results prove that the proposed model has excellent accuracy, robustness, and generalization in both point prediction and interval prediction, compared with various baseline models. • A mature data preprocessing technique, CEESMDAN, is developed. • A memory-based data ensemble approach is proposed based on memory features of data. • We propose a novel point prediction framework for crude oil prices. • We design an interval prediction system based on two objective functions. • Our system can provide useful guidance for both investors and managers. [ABSTRACT FROM AUTHOR]

We report the intergrowth of ZIF-8 crystals on ultrathin graphene oxide (GO) membranes, which helps to reduce the non-selective pores of pristine GO membranes leading to gas selectivities as high as 406, 155, and 335 for H2/CO2, H2/N2, and H2/CH4 mixtures, respectively. [ABSTRACT FROM AUTHOR]

In a common, designed disposal system for high-level radioactive waste, bentonite is used worldwide as a buffer material due to its favorable thermodynamic properties. In-situ experiments at different scales are being conducted in several underground laboratories to investigate the long-term coupled thermo-hydro-mechanical (THM) and chemical behavior of bentonite. Simultaneously, numerous laboratory experiments under well-defined conditions were performed to determine the material properties of bentonite. Since 2012, a laboratory heating and hydration test on MX-80 bentonite has been performed by CIEMAT ( Centro de Investigaciones Energéticas , Medioambientales y Tecnológicas ). The obtained data during the test were analyzed by different research teams within the international DECOVALEX project in order to understand the coupled THM behavior of bentonite and furthermore to determine the thermal-mechanical properties of bentonite. This paper presents a numerical model for fully-coupled THM processes in bentonite based on the finite element method program OpenGeoSys (Kolditz et al., 2012a). In this model, the description of heat conduction is based on Fourier's law, and advection is also considered in the heat transfer. As an important coupling factor from hydraulic process to thermal process, the dependency of thermal conductivity on the water saturation is intensively analyzed. A multiphase flow model considering water evaporation and vapor diffusion is used to describe the hydraulic process. Special attention was also paid on the analysis of the water retention behavior. An elastic constitutive model based on generalized Hook's law was applied to describe the material's mechanical behavior complemented with consideration of the thermally induced strain and the swelling deformation. Good agreement between the calculated and measured data has been achieved concerning temperature, relative humidity, total stress, and water intake. The main coupling processes and bentonite behavior in the experiment could be captured and well analyzed in this model. However, further investigations are also needed, especially for the long-term THM process with respect to water intake. [ABSTRACT FROM AUTHOR]

CHA zeolite membranes were hydrothermally synthesized by secondary growth method. Original and ball-milled seeds were compared for induction of CHA zeolite membranes. The synthetic parameters were investigated extensively in terms of seed size, precursor composition and crystallization temperature. Impurity MER phase was readily generated in membrane layers when using original CHA seeds (average particle size ∼ 3.80 μm) in an individual K + -containing synthetic medium. Comparatively, pure phase CHA zeolite membranes could be obtained by induction of ball-milled seeds in a broad SiO 2 /Al 2 O 3 ratio and at a low K + concentration. The as-synthesized membranes showed better separation performance than those induced with original seeds. Typically, the CHA zeolite membrane synthesized at 433 K for 20 h in a synthesis gel of 11 SiO 2 :1 Al 2 O 3 :1 K 2 O:1 Na 2 O:550 H 2 O showed a water permeation flux of 2.5 kg m −2 h −1 and separation factor of 2980 for pervaporation dehydration of 90 wt.% ethanol solution at 348 K. The CHA zeolite membrane synthesized with ball-milled seeds was stable for dehydration of acidic ethanol solution (pH ∼3) at 348 K while the membrane induced with original seeds showed a declined separation behavior. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are superior sorbents for water adsorption‐based applications. The unique step‐like water isotherm at a MOF‐specific relative pressure allows easy loading and regeneration over a small range of temperature and pressure conditions. With good hydrothermal stability and cyclic durability, it stands out over classical sorbents used in applications for humidity control, water harvesting, and adsorption‐based heating and cooling. These are easily regenerated at moderate temperatures using “waste” heat or solar heating. The isotherm thermodynamics and adsorption mechanisms are described, and the presence of MOFs in the water–air system is explained. Based on six selection criteria ≈40 reported MOFs and one COF are identified for potential application. Trends and approaches in further synthesis optimization and production scale‐up are highlighted. No‐MOF‐fits‐all, each MOF has its own specific step location matching only with a certain application type. Most applications are technically feasible and demonstrated on the bench‐scale or small pilot. Their maturity is benchmarked by their technology readiness level. Retrofitting existing applications with MOFs replacing classical desiccants may lead to rapid demonstration. Studies on techno‐economic analysis and life cycle analysis are required for a rational evaluation of the feasibility of promising applications. [ABSTRACT FROM AUTHOR]

Quad-plane is a popular type of electric vertical and takeoff/landing (eVTOL) vehicle that hybridizes a quadrotor and a fixed-wing airplane. However, the mechanical simplicity of a quad-plane also makes it vulnerable to rotor failures. When a complete rotor fails, it becomes physically impossible to stop the quad-plane from fast yaw spinning, which further induces considerable abnormal aerodynamic forces and moments on the wing. In this paper, a novel incremental adaptive sliding mode control (I-ASMC) is proposed to address these challenges. First, by exploiting sensor measurements, it simultaneously reduces the control model dependency and the minimum possible sliding mode control/observer gains. Second, finite-time convergence is guaranteed in the Lyapunov sense. Third, the control gains are automatically adapted to their minimum possible values without prior-knowledge on the uncertainty bounds. The proposed I-ASMC method is verified on a high fidelity simulation platform with computational fluid dynamic (CFD) aerodynamic models. Simulation results demonstrate that I-ASMC can drive a quad-plane with a complete loss of a single rotor to follow a trajectory. Its robustness to aerodynamic model uncertainties and rotor faults is also better than the linear quadratic regulator (LQR) and the incremental nonlinear dynamic inversion (INDI) control. In conclusion, the reduced model dependency, implementation simplicity, and improved robustness make the proposed I-ASMC promising for enhancing quad-plane safety in real life. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations were performed to examine the substituent effects on the interconversion of silabenzenes and their monocyclic non-aromatic isomers. A previous study suggested that aromaticity is the driving force for this process. Interestingly, our systematic calculations reveal that the contribution from aromaticity can be evaluated quantitatively (ca. 30 kcal mol −1 ). Thus it is the interplay of aromaticity and Bent's rule that determines their relative stabilities. In addition, strong correlations of reaction energies as well as reaction barriers have been identified against the s character of Si in the Si-X bonds, providing an important guide to the synthesis of silabenzenes. [ABSTRACT FROM AUTHOR]

• The revised FSI models with cavitation and turbulent effects are proposed. • Effects of grooves types and locations towards the FSI behaviors are explored. • The mechanism of the separation effects of the grooves coupled with the rotation effects are revealed. • Stimulations are consistent with the literature and experimental data, indicating the correctness of the model. The work studies the fluid structure interaction (FSI) dynamic behaviors of water-lubricated bearing with axial asymmetric grooves. Revised FSI models with consideration of cavitation and turbulent effects are put forward. Stimulations are consistent with the literature and experimental data, indicating the correctness of the model. Effects of groove types, locations in ascending/descending zones towards the dynamic behaviors are explored in details systematically. The separation effects of the local asymmetric grooves coupled with the rotation effects further enhances the hydrodynamic effects, which will directly lead to the growth of maximum pressure values and the load carrying capacity (LCC). Research fruits have important guiding significances for the optimization design of the surface microstructures and micro-textures, especially the design of axial asymmetric grooves for such bearings. [ABSTRACT FROM AUTHOR]

Metallaaromatics have attracted considerableinterest from bothexperimentalists and theoreticians over the past three decades. However,most studies in this field have focused on metallabenzene, in whicha CH group is replaced by a transition metal fragment. In comparisonwith monocyclic metallabenzenes, bicyclic metallanaphthalenes arerather limited. Thus, it is urgent to explore more synthetic approachesto this less developed system. One of the difficulties in the synthesisof metallanaphthalenes could be due to its low thermodynamic stabilityrelative to the metal indenyl complexes. Here we present a thoroughtheoretical investigation by quantum chemical calculations to explorethe possibility of realizing traditionally “unstable”metallanaphthalenes by an isomerization of traditionally “stable”metal indenyl complexes. We systematically investigated how differentsubstituent(s) at different position(s) on the metallacycle affectsuch a rearrangement. Our results indicate that although indenyl complexesare known to be thermally robust, it should be possible to shift thethermodynamic and kinetic balance toward the metallanaphthalene complexesby choosing proper ancillary substituents on the metallabicycle, whichis in sharp contrast to the traditional facile isomerization of metallabenzenesto cyclopentadienyl (Cp) complexes. Therefore, our findings suggesta novel avenue to metallanaphthalenes. [ABSTRACT FROM AUTHOR]

Abstract: T-type zeolite membranes were prepared on thin yttria-stabilized zirconia (YSZ) hollow fiber substrates by secondary growth method. Prior to membrane synthesis, the outer surface of YSZ hollow fibers were planted with T-type zeolite seeds. Extensive investigation on membrane synthesis was carried out in terms of seeding method, synthesis temperature, crystallization time and precursor composition. High-quality hollow fiber T-type zeolite membranes were synthesized at 100°C for 40h using milk-like aluminosilicate gel (SiO2:Al2O3:Na2O:K2O:H2O=1:0.05:0.26:0.09:17 in mol) as a synthesis precursor. The as-synthesized membranes via the seeding approach of rubbing had well-intergrown zeolite layers with a thickness of ~12μm, which displayed high permeation flux for dehydration of organics. Typically, a water permeation flux of 7.36kgm−2 h−1 with separation factor of >10,000 was obtained for dehydration of 90wt% isopropanol solution at 75°C. The membrane synthesis via the seeding approach of vacuum-coating could produce hollow fiber T-type zeolite membranes in batch scale. High acid resistance for the membrane material was confirmed by dehydration of propanal solution with pH~4. Moreover, hollow fiber membrane modules with ca. 0.1m2 membrane area were fabricated and assembled for propanal dehydration to evaluate the technical feasibility. [Copyright &y& Elsevier]

In this paper, we establish an event-triggered intelligent control scheme with a single critic network, to cope with the optimal stabilization problem of nonlinear aeroelastic systems. The main contribution lies in the design of a novel triggering condition with input constraints, avoiding the Lipschitz assumption on the inverse hyperbolic tangent function. Based on an improved weight updating criterion that eliminates the requirement of initial admissible control, the control law is obtained approximately by online training of a single critic network. The Lyapunov stability and the Zeno phenomenon of the closed-loop system are analysed. The feasibility of the established algorithm is verified by applying it to an optimal stabilization task of a nonlinear aeroelastic system. The results reveal that the developed approach can handle input-constrained optimal control problems, with performance comparable to the time-based method that updates control inputs at each instant, while reducing the computational and communication's load. [ABSTRACT FROM AUTHOR]

A one-pot synthesis of pyrrolo[1,2- a]quinolin-1-ones has been developed from the reactions of 5-hydroxy-1-arylpyrrolidin-2-ones with 1,3-dicarbonyl compounds under the promotion of H3PO4/P2O5 or HOAc/H2SO4. The pyrrolo[1,2- a]quinolin-1-ones are formed by two-step reactions, that is, the coupling of N-acyliminium ion intermediates produced from 5-hydroxy-1-arylpyrrolidin-2-ones with 1,3-dicarbonyls and subsequent Friedel-Crafts reactions of the resulting ketone with the aryl ring. [ABSTRACT FROM AUTHOR]

Pure-silica MFI zeolite (silicalite-1) membranes exhibitgreat potential in the separation of an ethanol/water mixtures. Forsynthesis of silicalite membranes, however, conventional supportssuch as α-Al2O3and mullite have aluminumelement leaching out and entering into a zeolite structure, whichwould reduce the hydrophobicity of the zeolite layer and thus affectthe separation performance for ethanol selectivity. In this paper,we prepared silicalite membranes on hollow fiber substrates fabricatedwith yttria stabilized zirconia (YSZ) without aluminum. The influenceof seed size, synthesis parameters, and substrates was investigated.The as-synthesized membranes were characterized by scanning electronmicroscopy (SEM), electron probe microanalyzer (EPMA), infrared spectrumanalysis (IR), and X-ray diffraction (XRD). A thin MFI zeolite layerwith a thickness of about 3 μm could be formed on the support,which exhibited highly selective to ethanol over water. A high fluxof 7.4 kg m–2h–1with the separationfactor (ethanol/water) of 47 was achieved on the as-made membranefor separating 5 wt % ethanol/water at 60 °C. [ABSTRACT FROM AUTHOR]

Abstract: Photochemical and thermal cyclization of 4-(2-azidophenyl)-3,4-dihydropyrimidin-2-ones could afford fused indoles, such as 1,2,3a,9b-tetrahydro-4-methylenepyrimidino[5,4-b]indol-2-ones and 1,3,5,6,7a,12b-hexahydroquinazolino[9,4-b]indol-2,7-dione in high yields via nitrene electrophilic addition and rearrangement reactions. [ABSTRACT FROM AUTHOR]

Corrigendum: High-Silica CHA Zeolite Membrane with Ultra-High Selectivity and Irradiation Stability for Krypton/Xenon Separation The first sentence of the fourth paragraph in this section, "Herein we prepared high-silica CHA zeolite membranes on ceramic hollow fiber substrates for Kr/Xe separation." should be revised to read "Herein we prepared high-silica CHA zeolite membranes on ceramic disk substrates for Kr/Xe separation." Keywords: CHA zeolite; gas separation; krypton; membrane; xenon EN CHA zeolite gas separation krypton membrane xenon 21094 21094 1 09/16/21 20210920 NES 210920 In the Introduction section of this Research Article, the description on the membrane geometry was incorrect. [Extracted from the article]

Keywords: CHA zeolite; gas separation; krypton; membrane; xenon EN CHA zeolite gas separation krypton membrane xenon 21262 21262 1 09/16/21 20210920 NES 210920 In the Introduction section of this Research Article, the description on the membrane geometry was incorrect. The first sentence of the fourth paragraph in this section, "Herein we prepared high-silica CHA zeolite membranes on ceramic hollow fiber substrates for Kr/Xe separation." should be revised to read "Herein we prepared high-silica CHA zeolite membranes on ceramic disk substrates for Kr/Xe separation." Berichtigung: High-Silica CHA Zeolite Membrane with Ultra-High Selectivity and Irradiation Stability for Krypton/Xenon Separation. [Extracted from the article]

• Fast and cost-effective method developed for quantitative analysis of RAC. • A best performance for detecting RAC was achieved by PLSR and SGS-SIN-SDT. • Good predictive results were obtained for RAC in urine (R 2 = 0.997, RPD = 18.756). Ractopamine (RAC) is banned for use in swine to improve carcass leanness in the vast majority of countries and areas because its residue may pose health risks. This study investigated the feasibility of applying Fourier transform infrared (FT-IR) spectroscopy ranging from 4000 to 400 cm−1 for analysis of RAC concentration in swine urine. RAC of 0–0.20 μg/mL was added to urine samples collected from 15 swines to prepare a total of 110 samples, which were dried at 40 °C for 48 h before spectra acquisition. By using the whole spectra pretreated by Savitzky-Golay smoothing (SGS)-spectral intensity normalization (SIN)-second derivative transformation (SDT), an optimal partial least squares regression (PLSR) model was obtained with a determination coefficient (R 2) of 0.997 and a ratio of performance to deviation (RPD) of 18.756 for determining the RAC. Excitedly, 25 important wavenumbers could also be used to build a better PLSR model with R 2 of 0.924 and RPD of 3.68. Compounds in swine urine could cause the shifts of some vibration peaks of RAC such as N H and O H via intermolecular interactions. The satisfactory results indicated that FT-IR spectroscopy combined with sample drying and spectra pretreatment has a great potential for rapid analysis of ractopamine in swine urine. [ABSTRACT FROM AUTHOR]

• NXT ameliorates memory deficit in APP/PS1 mice. • NXT reduces p-Tau and Aβ plaques in APP/PS1 mouse brain. • NXT decreases inflammation levels in APP/PS1 mouse brain. • In vitro , NXT-EES reduces L-Glu-induced ROS and apoptosis. Alzheimer's disease (AD) is the most common neurodegenerative disease in aging population. Neuroinflammation, hyperphosphorylated Tau (p-Tau) and the imbalance between production and clearance of β-amyloid peptide (Aβ) are the major causes for AD development. NaoXinTong Capsule (NXT), a traditional Chinese medicine, is wildly used for treatment of cardiovascular and cerebrovascular diseases. Hence, we used the double transgenic mice expressing chimeric human amyloid precursor protein and mutant human presenilin 1 (APP/PS1) and HT-22 cells to determine the neuroprotective effects of NXT in AD development and the involved mechanisms. The 3-month-old APP/PS1 mice were randomly divided into 3 groups and received following treatment: Control group, mice were fed normal chow; NXT groups, mice were fed normal chow containing NXT at a normal and a high dose, respectively. While the age-matched C57BL/6J mice fed normal chow were used as the normal control. The NXT treatment was lasted for 5 months. We found that NXT treatment improved spatial memory impairment and cognitive decline in APP/PS1 mice by decreasing p-Tau levels and Aβ accumulation in the brain. Mechanistically, we observed that NXT inhibited neuron atrophy and apoptosis by downregulating inflammatory cytokines, interleukin 1β (IL-1β), IL-6 and tumor necrosis factor α (TNF-α), and inflammation mediators, nuclear factor κB (NF-κB) and toll-like receptor 4 (TLR4) in the brain. Consistently, NXT blocked l -glutamic acid-induced reactive oxygen species production, inflammation and apoptosis in HT-22 cells partially by inhibiting TLR4/NF-κB/IL-1β signaling pathway. Our study demonstrates that NXT ameliorates AD by reducing p-Tau, Aβ accumulation, inflammation and neuron apoptosis via regulation of TLR4-mediated inflammatory system. It also suggests the potential application of NXT for AD treatment. [ABSTRACT FROM AUTHOR]

• Transient cement kinetics model of different temperature and pressure is proposed. • Transient temperature model is established considering cement hydration reaction. • Transient pressure model is established considering cement hydration reaction. • The important hydration performances are analyzed by numerical simulation. Current researches on cement hydration reaction are based on the isothermal or isobaric condition in laboratory. Regarding practical applications, a new model of cement hydration performance under a wide range of temperature and pressure is established considering the complicated interactions among the temperature, pressure and cement hydration reaction. The interactions include: transient change of temperature and pressure under the effect of cement hydration; variations of cement hydration performances with positions due to the distribution of temperature and pressure; transient change of cement hydration performances under the effect of transient temperature and pressure. In addition, the new model was validated through a field application, which demonstrates good agreement. Through numerical simulations, some of the most important hydration performance are analyzed including the degree of hydration, temperature, pressure, gel strength and chemical shrinkage. The models and conclusions in this paper can help troubleshoot performance problems and provide safety guidance during cement design. [ABSTRACT FROM AUTHOR]

• An effective porosity approach was proposed for describing permeability variation during microbially induced calcite precipitation. • The performance of using different porosity-permeability relationships to simulate the permeability change during microbially induced calcite precipitation has been discussed. • The predictive ability of the model has been estimated through simulations of laboratory tests under different treatment strategies. • The effects of the reaction rate on the spatial and temporal evolution of the precipitated calcite were analyzed. Microbially induced calcite precipitation (MICP) provides the potential for developing innovative and environmentally friendly techniques to improve the engineering properties of soil through reduction of permeability in soil and increase of soil stiffness and strength. In the present research work, coupled bio-chemo-hydraulic modelling was developed to enhance the understanding of the coupled processes involved in MICP and to predict the MICP performance in permeability reduction. In the model, an overall kinetically controlled model is adopted to describe the biochemical reactions, where the reaction rate is dependent on the concentration of both bacteria and chemical reactants. Specifically, an effective porosity concept was proposed and implemented in the model to capture the effects of pore throat blockage on permeability reduction caused by precipitated calcite. Correspondingly, the Kozeny-Carman equation was modified to describe the permeability variation during MICP. This model has been applied to simulate two laboratory experiments. The observed changes in chemical components and hydraulic conductivity can be well reproduced in the model. Through comparisons of the effective porosity concept to other commonly used porosity-permeability relationships, it is estimated that effective porosity should be considered to simulate the permeability reduction observed in MICP. Furthermore, a sensitivity analysis of the reaction-related parameters was conducted. The results of the sensitivity analysis indicate that the maximum urease rate has a strong influence on the biochemical hydraulic responses in MICP. [ABSTRACT FROM AUTHOR]

Arsenic trioxide (ATO) has a significant effect on the treatment of acute promyelocytic leukemia (APL) and advanced primary liver cancer, but it still faces severe side effects. Considering these problems, red blood cell membrane-camouflaged ATO-loaded sodium alginate nanoparticles (RBCM-SA-ATO-NPs, RSANs) were developed to relieve the toxicity of ATO while maintaining its efficacy. ATO-loaded sodium alginate nanoparticles (SA-ATO-NPs, SANs) were prepared by the ion crosslinking method, and then RBCM was extruded onto the surface to obtain RSANs. The average particle size of RSANs was found to be 163.2 nm with a complete shell-core bilayer structure, and the average encapsulation efficiency was 14.31%. Compared with SANs, RAW 264.7 macrophages reduced the phagocytosis of RSANs by 51%, and the in vitro cumulative release rate of RSANs was 95% at 84 h, which revealed a prominent sustained release. Furthermore, it demonstrated that RSANs had lower cytotoxicity as compared to normal 293 cells and exhibited anti-tumor effects on both NB4 cells and 7721 cells. In vivo studies further showed that ATO could cause mild lesions of main organs while RSANs could reduce the toxicity and improve the anti-tumor effects. In brief, the developed RSANs system provides a promising alternative for ATO treatment safely and effectively. [ABSTRACT FROM AUTHOR]

This paper proposes incremental nonsingular terminal sliding mode control for a class of multi-input and multi-output nonlinear systems considering model uncertainties, external disturbances, and sudden actuator faults. This method is free from singularity because it does not involve any negative fractional power. The convergence time in both reaching and sliding phases are proved to be finite. Moreover, by fully exploiting sensor measurements, the proposed incremental control method simultaneously reduces model dependency and the uncertainty remaining in the closed-loop system. The reduction of model dependency simplifies the implementation process and reduces the computational load, while the reduction of uncertainty decreases the minimum possible sliding mode control gains, which is beneficial to chattering reduction. These merits are verified by a quadrotor trajectory tracking problem. Simulation results demonstrate that the proposed method has better robustness against model uncertainties, gusts, and actuator faults than the model-based nonsingular terminal sliding mode control in the literature. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive study based on multiphase-seepage and wellbore multiphase-flow theories. It establishes a model for calculating the rate of gas intrusion that considers various factors, including formation pore permeability, bottomhole pressure difference, rheology of the drilling fluid, and surface tension. Experiments were conducted to investigate the mechanism of gas intrusion under shut-in conditions, and the experimental results were employed to validate the reliability of the proposed method for calculating the gas intrusion rate. Furthermore, this research explores the transportation rates of single bubbles and bubble clusters in drilling fluid under shut-in conditions. Additionally, empirical expressions were derived for the drag coefficient for single bubbles and bubble clusters in the wellbore. These expressions can be used to calculate gas transportation rates for various equivalent radii of single bubbles and bubble clusters. The initial bubble size of intrusive gas, the transportation speed of intrusive gas in the wellbore, the rate of gas intrusion, and variations in the wellbore pressure after gas intrusion were analyzed. Additionally, a method was developed to calculate the rising velocity of bubble clusters in water based on experimental results. The study reveals that the average bubble size in the bubble cluster is significantly smaller than the size of single bubbles generated from the orifice. When the viscosity of the drilling fluid is low, the transportation velocity of the bubble cluster exhibits a positive correlation with the average bubble diameter. When the average bubble diameter exceeds 1 mm, the bubble velocity no longer varies with changes in the bubble-cluster diameter. The research results provide theoretical support for wellbore pressure prediction and pressure control under shutdown conditions. [ABSTRACT FROM AUTHOR]

Co‐hydrogenation of CO2/CO to produce ethanol presents an important way to utilize carbon‐neutralized biomass resources through gasification. By applying a water‐permselective membrane reactor, water, the byproduct of CO2/CO hydrogenation to ethanol, can be removed. Thus, ethanol formation can be promoted thermodynamically. Accordingly, herein, the thermodynamics of ethanol synthesis by CO2, CO, CO2/CO hydrogenation was investigated, as well as the promoting effects of water removal under various temperatures and pressures by Aspen Plus. It is found that, at medium reaction temperature (e.g., 250 °C), medium pressure (e.g., 10–50 bar), and medium CO fraction (e.g., 0.1–0.5) together with 1‐stage water removal, a CO2/CO equilibrium conversion higher than 80 % can be obtained. [ABSTRACT FROM AUTHOR]

Nitrite salts are widely presented in food and their hazardous effects have been well documented. In this study, we evaluated the protective capacity of chlorogenic acid (CGA) against sodium nitrite (NaNO2)‐induced damage to rat erythrocytes. Two dosing regimens of CGA were undertaken to alleviate the erythrocyte injury induced by NaNO2. We examined the cell fragility, the level of methemoglobin and oxidative stress parameters of each treated group. In result, as compared to the CGA post‐incubation, co‐incubation of CGA with NaNO2 decreased the content of advanced oxidation protein products. The protective capacity of CGA was superior to its remedial effect. We infer that the reaction of CGA and NaNO2 may suppress the cytotoxicity of nitrite on erythrocytes and avoid the generation of oxidative stress induced by NaNO2. Our results suggest a novel diet strategy for preventing the adverse effects of nitrite in those people with exposure to nitrite. Practical applications: Nitrite is ubiquitous in our environment and can also be formed from nitrogenous compounds by microorganisms which exist in the soil, water, and saliva. Several researches have been performed to explore the protection of natural products on the toxic effects of Nitrite. In this study, exogenous chlorogenic acid (CGA) is able to avert the membrane damage, lipid peroxidation, and morphology in nitrite‐induced erythrocytes. The protective capacity of CGA shows superior to the remediate effect of CGA against NaNO2 caused damage to erythrocytes. These results suggest a novel diet strategy for preventing the adverse effects of NaNO2 in those people with acute exposure to nitrite. [ABSTRACT FROM AUTHOR]

Detection of volatile organic compounds (VOCs) at parts-per-billion (ppb) level is one of the most challenging tasks for miniature gas sensors because of the high requirement on sensitivity and the possible interference from moisture. Herein, for the first time, we present a novel platform based on a hybrid photonic cavity with metal-organic framework (MOF) coatings for VOCs detection. We have fabricated a compact gas sensor with detection limitation ranging from 29 to 99 ppb for various VOCs including styrene, toluene, benzene, propylene and methanol. Compared to the photonic cavity without coating, the MOF-coated solution exhibits a sensitivity enhancement factor up to 1000. The present results have demonstrated great potential of MOF-coated photonic resonators in miniaturized gas sensing applications. [ABSTRACT FROM AUTHOR]

Abstract Hollow fiber supported CHA zeolite membranes with different Si/Al ratios in the framework were successfully synthesized by changing precursor compositions. The influence of precursor composition on the membrane composition, microstructure evolution and dehydration performances of CHA zeolite membranes, were extensively investigated. Pervaporation (PV) results indicated that the membrane separation performances were strongly influenced by both the framework Si/Al ratio and the microstructure of the membranes. The membranes with Si/Al ratio of ca. 2.7–2.8 composed of flake-like grains showed higher flux with relatively low selectivity, while the membrane with Si/Al ratio of >2.9 composed of block-shaped crystals exhibited higher separation factor of >10000. Both hydrothermal and acid stability of the membranes were dependent on the framework Si/Al ratio of CHA zeolite membranes. Graphical abstract Image 1 Highlights • CHA zeolite membranes with different Si/Al ratio were prepared. • Si/Al ratio affected the morphology of CHA zeolite membranes. • Si/Al ratio affected both hydrothermal and acid stability of the membrane. [ABSTRACT FROM AUTHOR]