The development of catalytic materials for the recycling CO_(2) through a myriad of available processes is an attractive field,especially given the current climate change.While there is increasing publication in this ...The development of catalytic materials for the recycling CO_(2) through a myriad of available processes is an attractive field,especially given the current climate change.While there is increasing publication in this field,the reported catalysts rarely deviate from the traditionally supported metal nanoparticle morphology,with the most simplistic method of enhancement being the addition of more metals to an already complex composition.Encapsulated catalysts,especially yolk@shell catalysts with hollow voids,offer answers to the most prominent issues faced by this field,coking and sintering,and further potential for more advanced phenomena,for example,the confinement effect,to promote selectivity or offer greater protection against coking and sintering.This work serves to demonstrate the current position of catalyst development in the fields of thermal CO_(2) reforming and hydrogenation,summarizing the most recent work available and most common metals used for these reactions,and how yolk@shell catalysts can offer superior performance and survivability in thermal CO_(2) reforming and hydrogenation to the more traditional structure.Furthermore,this work will briefly demonstrate the bespoke nature and highly variable yolk@shell structure.Moreover,this review aims to illuminate the spatial confinement effect and how it enhances yolk@shell structured nanoreactors is presented.展开更多
Data-driven process monitoring is an effective approach to assure safe operation of modern manufacturing and energy systems,such as thermal power plants being studied in this work.Industrial processes are inherently d...Data-driven process monitoring is an effective approach to assure safe operation of modern manufacturing and energy systems,such as thermal power plants being studied in this work.Industrial processes are inherently dynamic and need to be monitored using dynamic algorithms.Mainstream dynamic algorithms rely on concatenating current measurement with past data.This work proposes a new,alternative dynamic process monitoring algorithm,using dot product feature analysis(DPFA).DPFA computes the dot product of consecutive samples,thus naturally capturing the process dynamics through temporal correlation.At the same time,DPFA's online computational complexity is lower than not just existing dynamic algorithms,but also classical static algorithms(e.g.,principal component analysis and slow feature analysis).The detectability of the new algorithm is analyzed for three types of faults typically seen in process systems:sensor bias,process fault and gain change fault.Through experiments with a numerical example and real data from a thermal power plant,the DPFA algorithm is shown to be superior to the state-of-the-art methods,in terms of better monitoring performance(fault detection rate and false alarm rate)and lower computational complexity.展开更多
The chemical looping gasification uses an oxygen carrier for solid fuel gasification by supplying insufficient lattice oxygen. The effect of gasifying medium on the coal chemical looping gasification with Ca SO4 as ox...The chemical looping gasification uses an oxygen carrier for solid fuel gasification by supplying insufficient lattice oxygen. The effect of gasifying medium on the coal chemical looping gasification with Ca SO4 as oxygen carrier is investigated in this paper. The thermodynamical analysis indicates that the addition of steam and CO2 into the system can reduce the reaction temperature, at which the concentration of syngas reaches its maximum value.Experimental result in thermogravimetric analyzer and a fixed-bed reactor shows that the mixture sample goes through three stages, drying stage, pyrolysis stage and chemical looping gasification stage, with the temperature for three different gaseous media. The peak fitting and isoconversional methods are used to determine the reaction mechanism of the complex reactions in the chemical looping gasification process. It demonstrates that the gasifying medium(steam or CO2) boosts the chemical looping process by reducing the activation energy in the overall reaction and gasification reactions of coal char. However, the mechanism using steam as the gasifying medium differs from that using CO2. With steam as the gasifying medium, parallel reactions occur in the beginning stage, followed by a limiting stage shifting from a kinetic to a diffusion regime. It is opposite to the reaction mechanism with CO2 as the gasifying medium.展开更多
The inhibition ability of 4-amino-5-phenyl-4H-1, 2, 4-trizole-3-thiol （APTT）, ethylenediaminetetra-acetic acid （EDTA） and thiourea （TU） for mild steel corrosion in 1.0 moFL HC1 solution at 30 ℃ was investigated...The inhibition ability of 4-amino-5-phenyl-4H-1, 2, 4-trizole-3-thiol （APTT）, ethylenediaminetetra-acetic acid （EDTA） and thiourea （TU） for mild steel corrosion in 1.0 moFL HC1 solution at 30 ℃ was investigated. Tafel polarization and electrochemical impedance spectroscopy （EIS） were used to investigate the influence of these organic compounds as corrosion inhibitors of mild steel in 1.0 mol/L HC1 solution at 30 ℃. The inhibition mechanism was discussed in terms of Langrnuir isotherm model. Results obtained from Tafel polarization and impedance measurements are in a good agreement. The inhibition efficiency increases with the increase of the inhibitor concentration. The adsorption of the inhibitors on the mild steel surface follows Langmuir adsorption isotherm and the free energy of adsorption AGads indicates that the adsorption of APTT, EDTA, and TU molecules is a spontaneous process and a typical chemisorption.展开更多
In this paper, an efficient methodology for synthesizing the indirect work exchange networks(WEN) considering isothermal process and adiabatic process respectively based on transshipment model is first proposed. In co...In this paper, an efficient methodology for synthesizing the indirect work exchange networks(WEN) considering isothermal process and adiabatic process respectively based on transshipment model is first proposed. In contrast with superstructure method, the transshipment model is easier to obtain the minimum utility consumption taken as the objective function and more convenient for us to attain the optimal network configuration for further minimizing the number of units. Different from division of temperature intervals in heat exchange networks,different pressure intervals are gained according to the maximum compression/expansion ratio in consideration of operating principles of indirect work exchangers and the characteristics of no pressure constraints for stream matches. The presented approach for WEN synthesis is a linear programming model applied to the isothermal process, but for indirect work exchange networks with adiabatic process, a nonlinear programming model needs establishing. Additionally, temperatures should be regarded as decision variables limited to the range between inlet and outlet temperatures in each sub-network. The constructed transshipment model can be solved first to get the minimum utility consumption and further to determine the minimum number of units by merging the adjacent pressure intervals on the basis of the proposed merging methods, which is proved to be effective through exergy analysis at the level of units structures. Finally, two cases are calculated to confirm it is dramatically feasible and effective that the optimal WEN configuration can be gained by the proposed method.展开更多
By the virtue of their olfactory,physicochemical,and biological characteristics,essential oils(EOs)have drawn wide attention as additives in daily chemicals like perfume or personal care products.Nevertheless,they are...By the virtue of their olfactory,physicochemical,and biological characteristics,essential oils(EOs)have drawn wide attention as additives in daily chemicals like perfume or personal care products.Nevertheless,they are physicochemically unstable and susceptible to degradation or loss.Microencapsulation offers a feasible strategy to stabilize and prolong release of EO.This review summarizes the recognized benefits and functional properties of various preparation and characterization methods,wherein innovative fabrication strategies and their formation mechanisms are especially emphasized.Progress in combining detecting/measuring technologies with kinetic modelling are discussed,to give an integral approach of controlling the dynamic release of encapsulated EOs.Moreover,new development trends of EOs capsules are also highlighted.展开更多
The catalytic performance is highly related to the catalyst structure.Herein,a series of Ni nanoparticles supported on Y_(2)O_(3) with different morphologies were successfully synthesized via hydrothermal process scre...The catalytic performance is highly related to the catalyst structure.Herein,a series of Ni nanoparticles supported on Y_(2)O_(3) with different morphologies were successfully synthesized via hydrothermal process screening different pH environments.These Ni/Y_(2)O_(3)catalysts were applied to efficiently produce CO_(x)-free H2through ammonia decomposition.We identify a significant impact of Y_(2)O_(3)supports on nickel nanoclusters sizes and dispersion.The experimental results show that Ni/Y11 catalyst achieves 100% ammonia decomposition conversion under a gas hour space velocity(GHSV) of 12,000 ml·h^(-1)·gcat^(-1) and temperature of 650℃.Such a high level of activity over Ni/Y11 catalyst was attributed to a large specific surface area,appropriate alkalinity,and small Ni nanoparticles diameter with high dispersion.展开更多
Experimental results are presented which allow comparison of the electrochemical performance of RuO 2/Ti, Ru 0 3 Sn 0 7 O 2/Ti and Ru 0 3 V 0 7 O 2/Ti catalysts prepared on a titanium substrate by thermal decompositio...Experimental results are presented which allow comparison of the electrochemical performance of RuO 2/Ti, Ru 0 3 Sn 0 7 O 2/Ti and Ru 0 3 V 0 7 O 2/Ti catalysts prepared on a titanium substrate by thermal decomposition from respective precursors. The highest activity for chlorine evolution is observed on the Ru 0 3 V 0 7 O 2/Ti electrode, lower on Ru 0 3 Sn 0 7 O 2/Ti and least on RuO 2/Ti. Voltammograms obtained in the polarisable region are used to characterize the different electrodes. Further more an analysis of the catalytic activity and reaction kinetics of the developed electrodes in NaCl are presented.展开更多
The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions ad...The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions addition are presented. Continuous reaction crystallization of struvite MgNH4PO4 × 6H2O ran both under stoichiometric conditions and at 20% excess of magnesium ions (pH 9, t 900 s). It was concluded, that presence of copper (II) ions in a process system influenced product quality moderately advantageously. Mean size of struvite crystals enlarged by ca. 6% only. Lower concentration of phosphate (V) ions and excess of magnesium ions caused, that products of ca. 9% - 13% larger crystal mean size (up to ca.40mm) were removed from the crystallizer. Presence of struvite crystals and copper (II) hydroxide were detected analytically in the products (Cu in a product varied from 6 to 90 mg/kg). Presence of copper (II) ions favored crystallization of struvite in the form of tubular crystals.展开更多
The sonochemical decolorization of Methylene Orange was studied using a 24 kHz Ultrasound device with a 1.4 cm diameter horn. pH, power density, the effects of pH and power density on decolorization were discussed. Th...The sonochemical decolorization of Methylene Orange was studied using a 24 kHz Ultrasound device with a 1.4 cm diameter horn. pH, power density, the effects of pH and power density on decolorization were discussed. The combined effect of radiate time, the initial concentration of dyes and the addition of Fe^2＋ on the decolorization was studied using response surface methodology. The results showed that the factorial central composite design was successfully employed for experimental design and predication of the results. AtpH = 2.8, T=30℃, power denstity= 300 W/L and Fe^2＋ of 2 mg/L, the decolorization percentage of 5 mg/L dye solution reached 96% after 60 mill ultreatment. The rate of decolorization of the dye was greatly improved in the presence of Fe^2＋. The sonolysis of the dye followed first-order kinetics.展开更多
Low-temperature thermal energy conversions down to exergy zero to electric power must contribute energy sustainability. That is to say, reinforcements of power harvesting technologies from extremely low temperatures l...Low-temperature thermal energy conversions down to exergy zero to electric power must contribute energy sustainability. That is to say, reinforcements of power harvesting technologies from extremely low temperatures less than 373 K might be at least one of minimum roles for the current generations. Then, piezoelectric power harvesting process for recovering low-temperature heats was invented by using a unique biphasic operating medium of an underlying water-insoluble/low-boiling-point medium (i.e. NOVEC manufactured by 3M Japan Ltd.) in small quantity and upper-layered water in large quantity. The higher piezoelectric power harvesting densities were naturally revealed with an increase in heating temperatures. Excessive cooling of the operating medium deteriorated the power harvesting efficiency. The denser operating medium was surpassingly helpful to the higher piezoelectric power harvesting density. Concretely, only about 5% density increase of main operating medium (i.e. water with dissolving alum at 0.10 mol/dm3) came to the champion piezoelectric power harvesting density of 92.6 pW/dm2 in this study, which was about 1.4 times compared to that with the original biphasic medium of pure water together with a small quantity of NOVEC.展开更多
Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystall...Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystallizer with liquid jet pump device in 298 K assuming stoichiometric conditions. Struvite crystals of mean size Lm 5.2-23.0 μm were produced depending on pH (9-11) and mean residence time of suspension in a crystallizer τ (900-3600 s). Under these conditions linear growth rate of struvite crystals (SIG MSMPR kinetic model) decreased 2-time with the increase in pH and 3-time with the elongation of mean residence time of crystal suspension from 7.11×10-9 m/s (pH 9, τ900 s) to 1.65×10-9 m/s (pH 11, τ3600 s). Nucleation rate varied within the 7.9×108-1.8×1010 1/(sm3) limits. Struvite product of maximal linear size exceeded 100 μm with 10 vol. % of < 3 μm fraction corresponded to pH 9 and τ3600 s.展开更多
In this paper,the property degradation micromechanism of Al-5.10Cu-0.65 Mg-0.8Mn(wt%)alloy induced by 0.5 wt%Fe minor addition was revealed by atomic-scale scanning transmission electron microscopy and energy-dispersi...In this paper,the property degradation micromechanism of Al-5.10Cu-0.65 Mg-0.8Mn(wt%)alloy induced by 0.5 wt%Fe minor addition was revealed by atomic-scale scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy coupled with first-principles calculations.The results show that the Fe minor addition to the Al-Cu-Mg-Mn alloy leads to a slight reduction of grain size and the formation of coarse Al7Cu2Fe constituent particles.Fe tends to segregate into the T-phase dispersoids,θ'-,and S-phase precipitates by preferentially occupying Cu or Mn sites in these phase structures.The apparent Fe segregation contributes to an increase in stiffness of the T-phase and S-phase but decreased stiffness of theθ'phase.Formation of the coarse Al7Cu2Fe constituent particles and decreased stiffness of main precipitatesθ'containing Fe result in the degraded strength of the Al-Cu-Mg-Mn-Fe alloy.Further study reveals that corrosion resistance degradation of the Al-Cu-Mg-Mn-Fe alloy is associated with the increased width of precipitation free zones and consecutive grain boundary precipitates.The obtained results have significant implications for the usage of recycled Al alloys and the potential design strategies of high-performance alloys containing Fe.展开更多
Revealing the structure evolution of interfacial active species during a dynamic catalytic process is a challenging but pivotal issue for the rational design of high-performance catalysts.Here,we successfully prepare ...Revealing the structure evolution of interfacial active species during a dynamic catalytic process is a challenging but pivotal issue for the rational design of high-performance catalysts.Here,we successfully prepare sub-nanometric Pt clusters(~0.8 nm)encapsulated within the defects of CeO_(2)nanorods via an in-situ defect engineering methodology.The as-prepared Pt@d-CeO_(2)catalyst significantly boosts the activity and stability in the water-gas shift(WGS)reaction compared to other analogs.Based on controlled experiments and complementary(in-situ)spectroscopic studies,a reversible encapsulation induced by active site transformation between the Pt^(2+)-terminal hydroxyl and Pt^(δ+)-O vacancy species at the interface is revealed,which enables to evoke the enhanced performance.Our findings not only offer practical guidance for the design of high-efficiency catalysts but also bring a new understanding of the exceptional performance of WGS in a holistic view,which shows a great application potential in materials and catalysis.展开更多
Excessive nitrogen emission caused by human activities has significantly disrupted the global nitrogen cycle,adversely affecting ecosystems and human health.Electrocatalytic nitrate reduction to valuable ammonia(eNRA)...Excessive nitrogen emission caused by human activities has significantly disrupted the global nitrogen cycle,adversely affecting ecosystems and human health.Electrocatalytic nitrate reduction to valuable ammonia(eNRA)presents an encouraging alternative marked by mild reaction conditions,rapid reaction rates,and minimal byproduct pollution,successfully overcoming the challenges of the energy-intensive Haber-Bosch process.Recent innovations in two-dimensional(2D)electrocatalysts have emerged as a promising approach to enhance the efficiency and selectivity of this transformation.This review systematically examines the latest advancements in2D materials,including metals,metal compounds,nonmetallic elements,and organic frameworks,highlighting their unique electronic properties and high surface area that facilitate the electrocatalytic reactions.We explore strategies to optimize these catalysts,such as doping,heterostructure,and surface functionalization,which have shown significant improvements in catalytic performance.Furthermore,the role of in situ/operando characterization techniques in understanding the reaction mechanisms is highlighted,aiming to provide both theoretical and practical insights for the research and development of 2D nanoelectrocatalysts during eNRA.Additionally,future perspectives and ongoing challenges are discussed to offer insights for transitioning from experimental investigations to real-world applications.展开更多
Herein,a tandem electrocatalytic-catalytic method is employed to produce valuable alanine from nitrate and waste polylactic acid(PLA).Initially,two strategies are proposed to enhance the performance of electrocatalyti...Herein,a tandem electrocatalytic-catalytic method is employed to produce valuable alanine from nitrate and waste polylactic acid(PLA).Initially,two strategies are proposed to enhance the performance of electrocatalytic NO_(3)^(-)reduction reaction(NO_(3)^(-)RR):optimizing NO_(3)^(-)adsorption and accelerating water dissociation by modulating the cathode electrocatalyst.Fe-regulated Co nanosheets(Fe_(0.33)-Co(OH)_(2)NSs)have been developed as an efficient electrocatalyst,which demonstrate a remarkable Faradaic efficiency(FE)of 98.2%,with a corresponding yield rate of 10.7 mg h^(-1)cm^(-2)for NO_(3)RR to NH_(3)at-0.1 V vs.RHE.Additionally,~95%FEs of NH_(3)at-200 mA cm^(-2)have been maintained for>430 h in the alkaline solution.Subsequently,in situ technologies have been utilized to elucidate the NO_(3)^(-)RR pathways,the structure transformation of the electrocatalysts,and the effects of Fe-induced work function reduction and electron enrichment at Co sites on electrocatalytic activity.Finally,alanine is synthesized by using PLA and the generated NH_(3)as the raw reactants on the Ru/TiO_(2)catalyst,achieving maximum yield and selectivity of 81.3%and 91.8%,respectively,which provides a novel approach to utilize the nitrogen resource and mitigate plastic pollution.展开更多
G protein coupled receptor kinase 2 (GRK2) is a kinase that regulates cardiac signaling activity. Inhibiting GRK2 is a promising mechanism for the treatment of heart failure (HF). Further development and optimization ...G protein coupled receptor kinase 2 (GRK2) is a kinase that regulates cardiac signaling activity. Inhibiting GRK2 is a promising mechanism for the treatment of heart failure (HF). Further development and optimization of inhibitors targeting GRK2 are highly meaningful. Therefore, in order to design GRK2 inhibitors with better performance, the most active molecule was selected as a reference compound from a data set containing 4-pyridylhydrazone derivatives and triazole derivatives, and its scaffold was extracted as the initial scaffold. Then, a powerful optimization-based framework for de novo drug design, guided by binding affinity, was used to generate a virtual molecular library targeting GRK2. The binding affinity of each virtual compound in this dataset was predicted by our developed deep learning model, and the designed potential compound with high binding affinity was selected for molecular docking and molecular dynamics simulation. It was found that the designed potential molecule binds to the ATP site of GRK2, which consists of key amino acids including Arg199, Gly200, Phe202, Val205, Lys220, Met274 and Asp335. The scaffold of the molecule is stabilized mainly by H-bonding and hydrophobic contacts. Concurrently, the reference compound in the dataset was also simulated by docking. It was found that this molecule also binds to the ATP site of GRK2. In addition, its scaffold is stabilized mainly by H-bonding and π-cation stacking interactions with Lys220, as well as hydrophobic contacts. The above results show that the designed potential molecule has similar binding modes to the reference compound, supporting the effectiveness of our framework for activity-focused molecular design. Finally, we summarized the interaction characteristics of general GRK2 inhibitors and gained insight into their molecule-target binding mechanisms, thereby facilitating the expansion of lead to hit compound.展开更多
Rechargeable aqueous zinc(Zn)-metal batteries hold great promise for next-generation energy storage systems.However,their practical application is hindered by several challenges,including dendrite formation,corrosion,...Rechargeable aqueous zinc(Zn)-metal batteries hold great promise for next-generation energy storage systems.However,their practical application is hindered by several challenges,including dendrite formation,corrosion,and the competing hydrogen evolution reaction.To address these issues,we designed and fabricated a composite protective layer for Zn anodes by integrating carbon nanotubes(CNTs)with chitosan through a simple and scalable scraping process.The CNTs ensure uniform electric field distribution due to their high electrical conductivity,while protonated chitosan regulates ion transport and suppresses dendrite formation at the anode interface.The chitosan/CNTs composite layer also facilitates smooth Zn^(2+)deposition,enhancing the stability and reversibility of the Zn anode.As a result,the chitosan/CNTs@Zn anode demonstrates exceptional cycling stability,achieving over 3000 h of plating/stripping with minimal degradation.When paired with a V_(2)O_(5)cathode,the composite-protected anode significantly improves the cycle stability and energy density of the full cell.Techno-economic analysis confirms that batteries incorporating the chitosan/CNTs protective layer outperform those with bare Zn anodes in terms of energy density and overall performance under optimized conditions.This work provides a scalable and sustainable strategy to overcome the critical challenges of aqueous Zn-metal batteries,paving the way for their practical application in next-generation energy storage systems.展开更多
基金Financial support was provided by the Chinese Academy of Sciences–The World Academy of Sciences(CAS-TWAS)president fellowship。
文摘The development of catalytic materials for the recycling CO_(2) through a myriad of available processes is an attractive field,especially given the current climate change.While there is increasing publication in this field,the reported catalysts rarely deviate from the traditionally supported metal nanoparticle morphology,with the most simplistic method of enhancement being the addition of more metals to an already complex composition.Encapsulated catalysts,especially yolk@shell catalysts with hollow voids,offer answers to the most prominent issues faced by this field,coking and sintering,and further potential for more advanced phenomena,for example,the confinement effect,to promote selectivity or offer greater protection against coking and sintering.This work serves to demonstrate the current position of catalyst development in the fields of thermal CO_(2) reforming and hydrogenation,summarizing the most recent work available and most common metals used for these reactions,and how yolk@shell catalysts can offer superior performance and survivability in thermal CO_(2) reforming and hydrogenation to the more traditional structure.Furthermore,this work will briefly demonstrate the bespoke nature and highly variable yolk@shell structure.Moreover,this review aims to illuminate the spatial confinement effect and how it enhances yolk@shell structured nanoreactors is presented.
基金supported in part by the National Science Fund for Distinguished Young Scholars of China(62225303)the National Natural Science Fundation of China(62303039,62433004)+2 种基金the China Postdoctoral Science Foundation(BX20230034,2023M730190)the Fundamental Research Funds for the Central Universities(buctrc202201,QNTD2023-01)the High Performance Computing Platform,College of Information Science and Technology,Beijing University of Chemical Technology
文摘Data-driven process monitoring is an effective approach to assure safe operation of modern manufacturing and energy systems,such as thermal power plants being studied in this work.Industrial processes are inherently dynamic and need to be monitored using dynamic algorithms.Mainstream dynamic algorithms rely on concatenating current measurement with past data.This work proposes a new,alternative dynamic process monitoring algorithm,using dot product feature analysis(DPFA).DPFA computes the dot product of consecutive samples,thus naturally capturing the process dynamics through temporal correlation.At the same time,DPFA's online computational complexity is lower than not just existing dynamic algorithms,but also classical static algorithms(e.g.,principal component analysis and slow feature analysis).The detectability of the new algorithm is analyzed for three types of faults typically seen in process systems:sensor bias,process fault and gain change fault.Through experiments with a numerical example and real data from a thermal power plant,the DPFA algorithm is shown to be superior to the state-of-the-art methods,in terms of better monitoring performance(fault detection rate and false alarm rate)and lower computational complexity.
基金Supported by the Research and Development Program of the Korea Institute of Energy Research(KIER)(B4-2431-04)the National Natural Science Foundation of China(21276129,20876079)the Natural Science Funds for Distinguished Young Scholar in Shandong Province(JQ200904)
文摘The chemical looping gasification uses an oxygen carrier for solid fuel gasification by supplying insufficient lattice oxygen. The effect of gasifying medium on the coal chemical looping gasification with Ca SO4 as oxygen carrier is investigated in this paper. The thermodynamical analysis indicates that the addition of steam and CO2 into the system can reduce the reaction temperature, at which the concentration of syngas reaches its maximum value.Experimental result in thermogravimetric analyzer and a fixed-bed reactor shows that the mixture sample goes through three stages, drying stage, pyrolysis stage and chemical looping gasification stage, with the temperature for three different gaseous media. The peak fitting and isoconversional methods are used to determine the reaction mechanism of the complex reactions in the chemical looping gasification process. It demonstrates that the gasifying medium(steam or CO2) boosts the chemical looping process by reducing the activation energy in the overall reaction and gasification reactions of coal char. However, the mechanism using steam as the gasifying medium differs from that using CO2. With steam as the gasifying medium, parallel reactions occur in the beginning stage, followed by a limiting stage shifting from a kinetic to a diffusion regime. It is opposite to the reaction mechanism with CO2 as the gasifying medium.
基金Project(UKM-GUP-BTT-07-25-170) supported by Universiti Kebangsaan Malaysia
文摘The inhibition ability of 4-amino-5-phenyl-4H-1, 2, 4-trizole-3-thiol （APTT）, ethylenediaminetetra-acetic acid （EDTA） and thiourea （TU） for mild steel corrosion in 1.0 moFL HC1 solution at 30 ℃ was investigated. Tafel polarization and electrochemical impedance spectroscopy （EIS） were used to investigate the influence of these organic compounds as corrosion inhibitors of mild steel in 1.0 mol/L HC1 solution at 30 ℃. The inhibition mechanism was discussed in terms of Langrnuir isotherm model. Results obtained from Tafel polarization and impedance measurements are in a good agreement. The inhibition efficiency increases with the increase of the inhibitor concentration. The adsorption of the inhibitors on the mild steel surface follows Langmuir adsorption isotherm and the free energy of adsorption AGads indicates that the adsorption of APTT, EDTA, and TU molecules is a spontaneous process and a typical chemisorption.
基金Supported by the National Natural Science Foundation of China(21576036 and 21776035)
文摘In this paper, an efficient methodology for synthesizing the indirect work exchange networks(WEN) considering isothermal process and adiabatic process respectively based on transshipment model is first proposed. In contrast with superstructure method, the transshipment model is easier to obtain the minimum utility consumption taken as the objective function and more convenient for us to attain the optimal network configuration for further minimizing the number of units. Different from division of temperature intervals in heat exchange networks,different pressure intervals are gained according to the maximum compression/expansion ratio in consideration of operating principles of indirect work exchangers and the characteristics of no pressure constraints for stream matches. The presented approach for WEN synthesis is a linear programming model applied to the isothermal process, but for indirect work exchange networks with adiabatic process, a nonlinear programming model needs establishing. Additionally, temperatures should be regarded as decision variables limited to the range between inlet and outlet temperatures in each sub-network. The constructed transshipment model can be solved first to get the minimum utility consumption and further to determine the minimum number of units by merging the adjacent pressure intervals on the basis of the proposed merging methods, which is proved to be effective through exergy analysis at the level of units structures. Finally, two cases are calculated to confirm it is dramatically feasible and effective that the optimal WEN configuration can be gained by the proposed method.
基金This work is supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA16020405)National Natural Science Foundation of China(Nos.21821005,81772417,and 21902160)。
文摘By the virtue of their olfactory,physicochemical,and biological characteristics,essential oils(EOs)have drawn wide attention as additives in daily chemicals like perfume or personal care products.Nevertheless,they are physicochemically unstable and susceptible to degradation or loss.Microencapsulation offers a feasible strategy to stabilize and prolong release of EO.This review summarizes the recognized benefits and functional properties of various preparation and characterization methods,wherein innovative fabrication strategies and their formation mechanisms are especially emphasized.Progress in combining detecting/measuring technologies with kinetic modelling are discussed,to give an integral approach of controlling the dynamic release of encapsulated EOs.Moreover,new development trends of EOs capsules are also highlighted.
基金financially supported by the National Natural Science Foundation of China (Nos.21868016, 21763018,22005296 and 21875096)the Key Laboratory for Environment and Energy Catalysis of Jiangxi Province (No. 20181BCD40004)+1 种基金the Natural Science Foundation of Jiangxi Province (No.20181BAB203016)the Graduate Students Innovation Special Foundation of Jiangxi Province (No.YC2021-B014)。
文摘The catalytic performance is highly related to the catalyst structure.Herein,a series of Ni nanoparticles supported on Y_(2)O_(3) with different morphologies were successfully synthesized via hydrothermal process screening different pH environments.These Ni/Y_(2)O_(3)catalysts were applied to efficiently produce CO_(x)-free H2through ammonia decomposition.We identify a significant impact of Y_(2)O_(3)supports on nickel nanoclusters sizes and dispersion.The experimental results show that Ni/Y11 catalyst achieves 100% ammonia decomposition conversion under a gas hour space velocity(GHSV) of 12,000 ml·h^(-1)·gcat^(-1) and temperature of 650℃.Such a high level of activity over Ni/Y11 catalyst was attributed to a large specific surface area,appropriate alkalinity,and small Ni nanoparticles diameter with high dispersion.
文摘Experimental results are presented which allow comparison of the electrochemical performance of RuO 2/Ti, Ru 0 3 Sn 0 7 O 2/Ti and Ru 0 3 V 0 7 O 2/Ti catalysts prepared on a titanium substrate by thermal decomposition from respective precursors. The highest activity for chlorine evolution is observed on the Ru 0 3 V 0 7 O 2/Ti electrode, lower on Ru 0 3 Sn 0 7 O 2/Ti and least on RuO 2/Ti. Voltammograms obtained in the polarisable region are used to characterize the different electrodes. Further more an analysis of the catalytic activity and reaction kinetics of the developed electrodes in NaCl are presented.
文摘The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions addition are presented. Continuous reaction crystallization of struvite MgNH4PO4 × 6H2O ran both under stoichiometric conditions and at 20% excess of magnesium ions (pH 9, t 900 s). It was concluded, that presence of copper (II) ions in a process system influenced product quality moderately advantageously. Mean size of struvite crystals enlarged by ca. 6% only. Lower concentration of phosphate (V) ions and excess of magnesium ions caused, that products of ca. 9% - 13% larger crystal mean size (up to ca.40mm) were removed from the crystallizer. Presence of struvite crystals and copper (II) hydroxide were detected analytically in the products (Cu in a product varied from 6 to 90 mg/kg). Presence of copper (II) ions favored crystallization of struvite in the form of tubular crystals.
文摘The sonochemical decolorization of Methylene Orange was studied using a 24 kHz Ultrasound device with a 1.4 cm diameter horn. pH, power density, the effects of pH and power density on decolorization were discussed. The combined effect of radiate time, the initial concentration of dyes and the addition of Fe^2＋ on the decolorization was studied using response surface methodology. The results showed that the factorial central composite design was successfully employed for experimental design and predication of the results. AtpH = 2.8, T=30℃, power denstity= 300 W/L and Fe^2＋ of 2 mg/L, the decolorization percentage of 5 mg/L dye solution reached 96% after 60 mill ultreatment. The rate of decolorization of the dye was greatly improved in the presence of Fe^2＋. The sonolysis of the dye followed first-order kinetics.
文摘Low-temperature thermal energy conversions down to exergy zero to electric power must contribute energy sustainability. That is to say, reinforcements of power harvesting technologies from extremely low temperatures less than 373 K might be at least one of minimum roles for the current generations. Then, piezoelectric power harvesting process for recovering low-temperature heats was invented by using a unique biphasic operating medium of an underlying water-insoluble/low-boiling-point medium (i.e. NOVEC manufactured by 3M Japan Ltd.) in small quantity and upper-layered water in large quantity. The higher piezoelectric power harvesting densities were naturally revealed with an increase in heating temperatures. Excessive cooling of the operating medium deteriorated the power harvesting efficiency. The denser operating medium was surpassingly helpful to the higher piezoelectric power harvesting density. Concretely, only about 5% density increase of main operating medium (i.e. water with dissolving alum at 0.10 mol/dm3) came to the champion piezoelectric power harvesting density of 92.6 pW/dm2 in this study, which was about 1.4 times compared to that with the original biphasic medium of pure water together with a small quantity of NOVEC.
文摘Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystallizer with liquid jet pump device in 298 K assuming stoichiometric conditions. Struvite crystals of mean size Lm 5.2-23.0 μm were produced depending on pH (9-11) and mean residence time of suspension in a crystallizer τ (900-3600 s). Under these conditions linear growth rate of struvite crystals (SIG MSMPR kinetic model) decreased 2-time with the increase in pH and 3-time with the elongation of mean residence time of crystal suspension from 7.11×10-9 m/s (pH 9, τ900 s) to 1.65×10-9 m/s (pH 11, τ3600 s). Nucleation rate varied within the 7.9×108-1.8×1010 1/(sm3) limits. Struvite product of maximal linear size exceeded 100 μm with 10 vol. % of < 3 μm fraction corresponded to pH 9 and τ3600 s.
基金supported by the National Natural Science Foundation of China(Nos.U20A20274 and 52061003)the Natural Science Foundation of Yunnan Province(No.202301AT070209)the Science and Technology Major Project of Yunnan Province(No.202102AG050017).
文摘In this paper,the property degradation micromechanism of Al-5.10Cu-0.65 Mg-0.8Mn(wt%)alloy induced by 0.5 wt%Fe minor addition was revealed by atomic-scale scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy coupled with first-principles calculations.The results show that the Fe minor addition to the Al-Cu-Mg-Mn alloy leads to a slight reduction of grain size and the formation of coarse Al7Cu2Fe constituent particles.Fe tends to segregate into the T-phase dispersoids,θ'-,and S-phase precipitates by preferentially occupying Cu or Mn sites in these phase structures.The apparent Fe segregation contributes to an increase in stiffness of the T-phase and S-phase but decreased stiffness of theθ'phase.Formation of the coarse Al7Cu2Fe constituent particles and decreased stiffness of main precipitatesθ'containing Fe result in the degraded strength of the Al-Cu-Mg-Mn-Fe alloy.Further study reveals that corrosion resistance degradation of the Al-Cu-Mg-Mn-Fe alloy is associated with the increased width of precipitation free zones and consecutive grain boundary precipitates.The obtained results have significant implications for the usage of recycled Al alloys and the potential design strategies of high-performance alloys containing Fe.
文摘Revealing the structure evolution of interfacial active species during a dynamic catalytic process is a challenging but pivotal issue for the rational design of high-performance catalysts.Here,we successfully prepare sub-nanometric Pt clusters(~0.8 nm)encapsulated within the defects of CeO_(2)nanorods via an in-situ defect engineering methodology.The as-prepared Pt@d-CeO_(2)catalyst significantly boosts the activity and stability in the water-gas shift(WGS)reaction compared to other analogs.Based on controlled experiments and complementary(in-situ)spectroscopic studies,a reversible encapsulation induced by active site transformation between the Pt^(2+)-terminal hydroxyl and Pt^(δ+)-O vacancy species at the interface is revealed,which enables to evoke the enhanced performance.Our findings not only offer practical guidance for the design of high-efficiency catalysts but also bring a new understanding of the exceptional performance of WGS in a holistic view,which shows a great application potential in materials and catalysis.
基金supported by the National Natural Science Foundation of China(Nos.52172291,52122312,and 52473294)'Shuguang Program'supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.22SG31)the State Key Laboratory for Advanced Fiber Materials,Donghua University
文摘Excessive nitrogen emission caused by human activities has significantly disrupted the global nitrogen cycle,adversely affecting ecosystems and human health.Electrocatalytic nitrate reduction to valuable ammonia(eNRA)presents an encouraging alternative marked by mild reaction conditions,rapid reaction rates,and minimal byproduct pollution,successfully overcoming the challenges of the energy-intensive Haber-Bosch process.Recent innovations in two-dimensional(2D)electrocatalysts have emerged as a promising approach to enhance the efficiency and selectivity of this transformation.This review systematically examines the latest advancements in2D materials,including metals,metal compounds,nonmetallic elements,and organic frameworks,highlighting their unique electronic properties and high surface area that facilitate the electrocatalytic reactions.We explore strategies to optimize these catalysts,such as doping,heterostructure,and surface functionalization,which have shown significant improvements in catalytic performance.Furthermore,the role of in situ/operando characterization techniques in understanding the reaction mechanisms is highlighted,aiming to provide both theoretical and practical insights for the research and development of 2D nanoelectrocatalysts during eNRA.Additionally,future perspectives and ongoing challenges are discussed to offer insights for transitioning from experimental investigations to real-world applications.
基金supported by the National Key R&D Program of China(2022YFB4002700)the National Natural Science Foundation of China(22475071)the Shanghai Science and Technology Committee Rising-Star Program(22QA1403400)。
文摘Herein,a tandem electrocatalytic-catalytic method is employed to produce valuable alanine from nitrate and waste polylactic acid(PLA).Initially,two strategies are proposed to enhance the performance of electrocatalytic NO_(3)^(-)reduction reaction(NO_(3)^(-)RR):optimizing NO_(3)^(-)adsorption and accelerating water dissociation by modulating the cathode electrocatalyst.Fe-regulated Co nanosheets(Fe_(0.33)-Co(OH)_(2)NSs)have been developed as an efficient electrocatalyst,which demonstrate a remarkable Faradaic efficiency(FE)of 98.2%,with a corresponding yield rate of 10.7 mg h^(-1)cm^(-2)for NO_(3)RR to NH_(3)at-0.1 V vs.RHE.Additionally,~95%FEs of NH_(3)at-200 mA cm^(-2)have been maintained for>430 h in the alkaline solution.Subsequently,in situ technologies have been utilized to elucidate the NO_(3)^(-)RR pathways,the structure transformation of the electrocatalysts,and the effects of Fe-induced work function reduction and electron enrichment at Co sites on electrocatalytic activity.Finally,alanine is synthesized by using PLA and the generated NH_(3)as the raw reactants on the Ru/TiO_(2)catalyst,achieving maximum yield and selectivity of 81.3%and 91.8%,respectively,which provides a novel approach to utilize the nitrogen resource and mitigate plastic pollution.
基金supported by the National Natural Science Foundation of China Excellent Young Scientist Fund(22422801)the National Natural Science Foundation of China General Project(22278053)+1 种基金the National Natural Science Foundation of China General Project(22078041)Dalian High-level Talents Innovation Support Program(2023RQ059).
文摘G protein coupled receptor kinase 2 (GRK2) is a kinase that regulates cardiac signaling activity. Inhibiting GRK2 is a promising mechanism for the treatment of heart failure (HF). Further development and optimization of inhibitors targeting GRK2 are highly meaningful. Therefore, in order to design GRK2 inhibitors with better performance, the most active molecule was selected as a reference compound from a data set containing 4-pyridylhydrazone derivatives and triazole derivatives, and its scaffold was extracted as the initial scaffold. Then, a powerful optimization-based framework for de novo drug design, guided by binding affinity, was used to generate a virtual molecular library targeting GRK2. The binding affinity of each virtual compound in this dataset was predicted by our developed deep learning model, and the designed potential compound with high binding affinity was selected for molecular docking and molecular dynamics simulation. It was found that the designed potential molecule binds to the ATP site of GRK2, which consists of key amino acids including Arg199, Gly200, Phe202, Val205, Lys220, Met274 and Asp335. The scaffold of the molecule is stabilized mainly by H-bonding and hydrophobic contacts. Concurrently, the reference compound in the dataset was also simulated by docking. It was found that this molecule also binds to the ATP site of GRK2. In addition, its scaffold is stabilized mainly by H-bonding and π-cation stacking interactions with Lys220, as well as hydrophobic contacts. The above results show that the designed potential molecule has similar binding modes to the reference compound, supporting the effectiveness of our framework for activity-focused molecular design. Finally, we summarized the interaction characteristics of general GRK2 inhibitors and gained insight into their molecule-target binding mechanisms, thereby facilitating the expansion of lead to hit compound.
基金supported by the National Natural Science Foundation of China(22279139,62227815,22465026,22469015)the National Key R&D Program of China(2022YFA1504500)+1 种基金the Natural Science Foundation of Inner Mongolia Autonomous Region of China(2024JQ06,2022MS2010,2024MS05005)Inner Mongolia University Postgraduate Scientific Research Innovation Project(11200-5223737)。
文摘Rechargeable aqueous zinc(Zn)-metal batteries hold great promise for next-generation energy storage systems.However,their practical application is hindered by several challenges,including dendrite formation,corrosion,and the competing hydrogen evolution reaction.To address these issues,we designed and fabricated a composite protective layer for Zn anodes by integrating carbon nanotubes(CNTs)with chitosan through a simple and scalable scraping process.The CNTs ensure uniform electric field distribution due to their high electrical conductivity,while protonated chitosan regulates ion transport and suppresses dendrite formation at the anode interface.The chitosan/CNTs composite layer also facilitates smooth Zn^(2+)deposition,enhancing the stability and reversibility of the Zn anode.As a result,the chitosan/CNTs@Zn anode demonstrates exceptional cycling stability,achieving over 3000 h of plating/stripping with minimal degradation.When paired with a V_(2)O_(5)cathode,the composite-protected anode significantly improves the cycle stability and energy density of the full cell.Techno-economic analysis confirms that batteries incorporating the chitosan/CNTs protective layer outperform those with bare Zn anodes in terms of energy density and overall performance under optimized conditions.This work provides a scalable and sustainable strategy to overcome the critical challenges of aqueous Zn-metal batteries,paving the way for their practical application in next-generation energy storage systems.
