No matter whether a system is operated manually or automatically controlled by computer, the system’s vulnerability always exists. Earthquake Disaster Reduction System (EDRS) belongs to the category of information sy...No matter whether a system is operated manually or automatically controlled by computer, the system’s vulnerability always exists. Earthquake Disaster Reduction System (EDRS) belongs to the category of information system. According to the features of security for EDRS, the steps and the methods on how to build the EDRS security were analyzed. The EDRS security features, security strategies and security measures were also given through a distributed EDRS skeleton that has been applied. Because there was still no appointed and authoritative agency or organization to certify and test EDRS security in China, a national information technology security certification center was introduced and suggested for the certification of the EDRS security. Finally, several discussions and tendencies for the EDRS development were presented.展开更多
Through investigation on the international development trend of earthquake disaster reduction system(EDRS)researches,a well finished Daqing Oilfield EDRS is introduced.Based on the PC System,redevelopment of the EDRS ...Through investigation on the international development trend of earthquake disaster reduction system(EDRS)researches,a well finished Daqing Oilfield EDRS is introduced.Based on the PC System,redevelopment of the EDRS skeleton is well discussed,including the technical skeleton,function composition,structures of software and hardware,redevelopment languages,database,and remote linking and calling of analysis modules.Meanwhile,it is pointed out that extending and utilizing the function of remote sensing information on the basis of the current distributed EDRS skeleton will become another study direction of EDRS.展开更多
Stannous chloride dihydrate is used as an efficient catalyst in reductive cyclization of 2-nitro-5- substituted aniline Schiff base leading to stable 2,5-disubstitued benzimidazole derivatives in excellent yields with...Stannous chloride dihydrate is used as an efficient catalyst in reductive cyclization of 2-nitro-5- substituted aniline Schiff base leading to stable 2,5-disubstitued benzimidazole derivatives in excellent yields with good purity. It provides a novel method of synthesis of 2,5-disubstitued benzimidazole under reductive system at room temperature.展开更多
s: Vinous aromatic nitro compounds could be selectively and rapidly reduced to the corresponding amines in excellent yields by potassium borohydride - bismuth chloride/ethanol-water, a new and facile reductive system.
Water scarcity is an escalating global crisis,posing a severe threat to populations worldwide.Consequently,exploring various materials to remove emerging contaminants from freshwater sources has garnered significant a...Water scarcity is an escalating global crisis,posing a severe threat to populations worldwide.Consequently,exploring various materials to remove emerging contaminants from freshwater sources has garnered significant attention.In this regard,single-atom catalysis(SACs) has emerged as a catalyst of scientific progress in water purification and treatment methodologies during recent decades.SACs exhibit exceptional catalytic activity,selectivity and stability,due to their near-perfect atom utilization,highly unsaturated coordination environment and uniform reaction centers.However,a comprehensive and critical review encompassing the successful integration of SACs into water purification processes needs to be completed.This review aims to accentuate recent trends by presenting the synthesis,structure,and environment and energy application-relevant properties of SACs.The results show that a comprehensive and multi-perspective summary of the advantages of SACs in environmental remediation can have significant benefits,such as fast kinetics,costeffectiveness,selectivity.The oxidation and reduction processes of SACs and functional SACs materials in water purification were emphasized.Furthermore,the last section is devoted to the current research gaps and further perspectives on the application of SACs in water treatment,which are summarized and analyzed.展开更多
Solid waste and air pollution are never ending environmental problems that can be partially solved by turning waste into useful bio-products. In this study, enzymatic solutions were developed by formulating enzymatic ...Solid waste and air pollution are never ending environmental problems that can be partially solved by turning waste into useful bio-products. In this study, enzymatic solutions were developed by formulating enzymatic solutions from fish intestines and fruit peels. This aimed to help in biodegradation of organic solid wastes. Organic waste samples were treated with formulated enzymatic solutions for 7 days in aerated set-up for aerobic degradation. Biodegradability and odor of the waste samples were compared with commercial enzymatic solution. Determination of evolved carbon dioxide (CO2) using gravimetric analysis (GA) was used to determine the percent biodegradability, Dt, of organic solid waste and odor-ranking method was used to determine the odor intensity of the organic waste samples. The result showed that the weight loss and percentage biodegradability of organic waste sample treated with formulated enzymatic solution is comparable with that of the commercial enzymatic solution. In terms of odor intensity, waste treated with the product, formulated enzymatic solution (FES) is also comparable to the waste treated with commercial enzymatic solution. Thus, implying that the developed FES is as efficient as that of the commercial enzymatic solution. These significant results will be helpful to future researchers in providing ways on improving the degradation of organic solid waste and mitigating the increasing glitches on our environment. Enzyme kinetics, physical and chemical properties studies of the solution were recommended for future researchers to accurately determine the effectiveness of the formulated enzymatic solution in the degradation of organic solid waste.展开更多
In this study,we present a self-driven photoelectrocatalytic(SD-PEC)system that effectively treats complex uranium-bearing wastewaters for both uranium recovery and organic matter decomposition while generating power....In this study,we present a self-driven photoelectrocatalytic(SD-PEC)system that effectively treats complex uranium-bearing wastewaters for both uranium recovery and organic matter decomposition while generating power.The system utilizes a titanium dioxide nanorod array(TNR)photoelectrode coupled with a silicon solar cell to optimize electron transport,while the cathode is composed of a carbon fiber coated with carboxylated carbon nanotubes(CCNT/CF),which efficiently reduce UO_(2)^(2+).The results demonstrate significant removal efficiency of uranium(complete removal in 25 min at a rate constant of~0.248 min^(-1)),as well as substantial degradation of organic impurities.Furthermore,the system generates sufficient power output to light an LED lamp and exhibits superior performance under various complex wastewater conditions,including simulated seawater and real uranium tailings wastewater.These findings underscore the potential of the SD-PEC system as a versatile approach for sustainable treatment and energy recovery of radioactive wastewater.The significance of this research extends to global environmental challenges,offering an innovative solution for managing radioactive wastewater while simultaneously contributing to renewable energy generation.展开更多
This study demonstrates the electrochemical reduction of carbon monoxide(COR)at high current densities in a zero-gap electrolyzer cell and cell stack.By systematically optimizing both the commercially available membra...This study demonstrates the electrochemical reduction of carbon monoxide(COR)at high current densities in a zero-gap electrolyzer cell and cell stack.By systematically optimizing both the commercially available membrane electrode assembly components(including binder content and gas diffusion layer)and the operating conditions,we could perform COR at current densities up to 1.4 A cm^(-2)with a maximum C2+selectivity of 90%.We demonstrated the scale-up to a 3×100 cm^(2)electrolyzer stack that can sustain stable operation at 1 A cm^(-2)for several hours without significant performance decay and with a total C2+selectivity of~80%and an ethylene selectivity of~40%.We provide critical insights into the holistic optimization of key system parameters,without using special catalysts or surface additives,which can pave the way for scalable and industrially viable COR processes.展开更多
Layered transition metal hydroxides show distinct advantages in separately co-catalyzing CO_(2)reduction and H_(2)O oxidation at the electron-accumulating and hole-accumulating sites of wrapped heterojunction photocat...Layered transition metal hydroxides show distinct advantages in separately co-catalyzing CO_(2)reduction and H_(2)O oxidation at the electron-accumulating and hole-accumulating sites of wrapped heterojunction photocatalysts,while concurrently preventing side reactions and photocorrosion on the semiconductor surface.Herein,Ni-Co bimetallic hydroxides with varying Ni/Co molar ratios(Ni_(x)Co_(1-x)(OH)_(2),x=1,0.75,0.5,0.25,and 0)were grown in situ on a model 2D/2D S-scheme heterojunction composed of Cu_(2)O nanosheets and Fe_(2)O_(3)nanoplates to form a series of Cu_(2)O/Fe_(2)O_(3)@Ni_(x)Co_(1-x)(OH)_(2)(CF@NiCo)photocatalysts.The combined experimental and theoretical investigation demonstrates that incorporating an appropriate amount of Co into Ni(OH)_(2)not only modulates the energy band structure of Ni_(x)Co_(1-x)(OH)_(2),balances the electron-and hole-trapping abilities of the bifunctional cocatalyst and maximizes the charge separation efficiency of the heterojunction,but also regulates the d-band center of Ni_(x)Co_(1-x)(OH)_(2),reinforcing the adsorption and activation of CO_(2)and H_(2)O on the cocatalyst surface and lowering the rate-limiting barriers in the CO_(2)-to-CO and H_(2)O-to-O_(2)conversion.Benefiting from the Ni-Co synergy,the redox reactions proceed stoichiometrically.The optimized CF@Ni_(0.75)Co_(0.25)achieves CO and O_(2)yields of 552.7 and 313.0μmol gcat^(-1)h^(-1),respectively,11.3/9.9,1.6/1.7,and 4.5/5.9-fold higher than those of CF,CF@Ni,and CF@Co.This study offers valuable insights into the design of bifunctional noble-metal-free cocatalysts for high-performance artificial photosynthesis.展开更多
Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespr...Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespread attention for CO_(2)RR due to their high catalytic activity,selectivity,excellent stability,and low cost.However,they still need to be further improved to meet the needs of industrial applications.This review article comprehensively summarizes the recent advances in regulation strategies of Bi-based catalysts and can be divided into six categories:(1)defect engineering,(2)atomic doping engineering,(3)organic framework engineering,(4)inorganic heterojunction engineering,(5)crystal face engineering,and(6)alloying and polarization engineering.Meanwhile,the corresponding catalytic mechanisms of each regulation strategy will also be discussed in detail,aiming to enable researchers to understand the structure-property relationship of the improved Bibased catalysts fundamentally.Finally,the challenges and future opportunities of the Bi-based catalysts in the photoelectrocatalytic CO_(2)RR application field will also be featured from the perspectives of the(1)combination or synergy of multiple regulatory strategies,(2)revealing formation mechanism and realizing controllable synthesis,and(3)in situ multiscale investigation of activation pathways and uncovering the catalytic mechanisms.On the one hand,through the comparative analysis and mechanism explanation of the six major regulatory strategies,a multidimensional knowledge framework of the structure-activity relationship of Bi-based catalysts can be constructed for researchers,which not only deepens the atomic-level understanding of catalytic active sites,charge transport paths,and the adsorption behavior of intermediate products,but also provides theoretical guiding principles for the controllable design of new catalysts;on the other hand,the promising collaborative regulation strategies,controllable synthetic paths,and the in situ multiscale characterization techniques presented in this work provides a paradigm reference for shortening the research and development cycle of high-performance catalysts,conducive to facilitating the transition of photoelectrocatalytic CO_(2)RR technology from the laboratory routes to industrial application.展开更多
Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when ta...Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when tackling high-dimensional optimization challenges.To effectively address these challenges,this study introduces cooperative metaheuristics integrating dynamic dimension reduction(DR).Building upon particle swarm optimization(PSO)and differential evolution(DE),the proposed cooperative methods C-PSO and C-DE are developed.In the proposed methods,the modified principal components analysis(PCA)is utilized to reduce the dimension of design variables,thereby decreasing computational costs.The dynamic DR strategy implements periodic execution of modified PCA after a fixed number of iterations,resulting in the important dimensions being dynamically identified.Compared with the static one,the dynamic DR strategy can achieve precise identification of important dimensions,thereby enabling accelerated convergence toward optimal solutions.Furthermore,the influence of cumulative contribution rate thresholds on optimization problems with different dimensions is investigated.Metaheuristic algorithms(PSO,DE)and cooperative metaheuristics(C-PSO,C-DE)are examined by 15 benchmark functions and two engineering design problems(speed reducer and composite pressure vessel).Comparative results demonstrate that the cooperative methods achieve significantly superior performance compared to standard methods in both solution accuracy and computational efficiency.Compared to standard metaheuristic algorithms,cooperative metaheuristics achieve a reduction in computational cost of at least 40%.The cooperative metaheuristics can be effectively used to tackle both high-dimensional unconstrained and constrained optimization problems.展开更多
NA novel smelting reduction process based on FeO-SiO2-Al2O3 slag system for spent lithium ion batteries with Al cans was developed, while using copper slag as the only slag former. The feasibility of the process and t...NA novel smelting reduction process based on FeO-SiO2-Al2O3 slag system for spent lithium ion batteries with Al cans was developed, while using copper slag as the only slag former. The feasibility of the process and the mechanism of copper loss in slag were investigated. 98.83% Co, 98.39% Ni and 93.57% Cu were recovered under the optimum conditions of slag former/battery mass ratio of 4.0：1, smelting temperature of 1723 K, and smelting mass ratio of time of 30 min. The FeO-SiO2-Al2O3 slag system for the smelting process is appropriate under the conditions of m（FeO）：m（SiO2）=0.58：1？1.03：1, and 17.19%？21.52% Al2O3 content. The obtained alloy was mainly composed of Fe-Co-Cu-Ni solid solution including small amounts of matte. The obtained slag mainly consisted of fayalite and hercynite. Meanwhile, the mechanism of copper loss is the mechanical entrainment from strip-like fayalite particles in the main form of copper sulfide and metallic copper.展开更多
The reduction behaviors and characteristics of products of the Fe-Cr-O system （FeCr2O4 and Fe2O3＋Cr2O3） and Fe-Cr-Ni-O system （Fe2O3＋Cr2O3＋NiO） under various conditions were studied. The results show that more ...The reduction behaviors and characteristics of products of the Fe-Cr-O system （FeCr2O4 and Fe2O3＋Cr2O3） and Fe-Cr-Ni-O system （Fe2O3＋Cr2O3＋NiO） under various conditions were studied. The results show that more Fe-Cr or Fe-Cr-Ni solution and less residual carbon content were obtained at higher temperatures and lower initial molar ratio of C to O （nC：nO）. The degree of reduction was highly dependent on both time and temperature, and the residual carbon content greatly increased with increasing nC：nO at each temperature. The products generated during the carbothermic reduction of the Fe-Cr-O system were examined using X-ray diffraction （XRD）. A scanning electron microscope （SEM） coupled with energy dispersive spectrometer was used to observe the microstructure and the distribution of elements in the various phases of the final reduction products of the Fe-Cr-O and Fe-Cr-Ni-O.展开更多
We explores Hamiltonian reduction in pulse-controlled finite-dimensional quantum systems with near-degenerate eigenstates. A quantum system with a non-degenerate ground state and several near-degenerate excited states...We explores Hamiltonian reduction in pulse-controlled finite-dimensional quantum systems with near-degenerate eigenstates. A quantum system with a non-degenerate ground state and several near-degenerate excited states is controlled by a short pulse, and the objective is to maximize the collective population on all excited states when we treat all of them as one level. Two cases of the systems are shown to be equivalent to effective two-level systems. When the pulse is weak, simple relations between the original systems and the reduced systems are obtained. When the pulse is strong, these relations are still available for pulses with only one frequency under the first-order approximation.展开更多
Refer to the Hamiltonian system, first integrals of the Birkhoffian system can be found by using of the perfect differential method. Through these first integrals, the order of the Birkhoffian system can be reduced. T...Refer to the Hamiltonian system, first integrals of the Birkhoffian system can be found by using of the perfect differential method. Through these first integrals, the order of the Birkhoffian system can be reduced. Then according to the alternate of the coordinate, a kind of new partial differential operator was defined in order to hold the Birkhoff form. The result shows that the Birkhoffian system has generalized energy integrals and cyclic integrals. Furthermore, each integral can reduce the order of equations two degrees.展开更多
As a global pollutant process, the reduction of mercury （Hg） is especially important. One pathway is through an abiotic reduction with humic acids （HAs）, which is controlled by different factors, including initial...As a global pollutant process, the reduction of mercury （Hg） is especially important. One pathway is through an abiotic reduction with humic acids （HAs）, which is controlled by different factors, including initial Hg and HA concentrations, pH, temperature and light. In this study, three humic acids were selected to illustrate the Hg2＋ abiotic reduction mechanisms by HAs, and to identify the key limiting factors for reduction rates and amounts. In addition, the initial status of the HAs as a solid or in an aqueous solution were also compared, to help explain why HAs show different dominant characteristics （e.g. complexation or reduction） in the reaction process with Hg. Results indicated that HAs were able to reduce Hg abiotically. Higher initial Hg, higher HA concentrations and either high （8.1） or low （3.6） solution pH decreased the HA reduction capacity. In addition, Hg~ production rates increased with increasing temperature, and the same trend was observed with light exposure. Humic acids added as an aqueous solution resulted in significantly greater HgO production than addition as a bulk solid. Finally, the Hg reduction rate and capacity varied significantly （P 〈 0.05） with HAs from different sources. These findings helped to explain why HAs showed different dominant characteristics （e.g. complexation or reduction） in the reaction process with of Hg2＋ reduction, which indicated that humic substances in sink or a source for Hg. Hg, and evidentially demonstrated the existence of a possible pathway natural environments, especially in water bodies, could act either as a展开更多
Selective catalytic reduction(SCR) denitration may increase the emission of NH4+and NH3.The removal and transformation characteristics of ammonium sulfate aerosols and ammonia slip during the wet flue gas desulfurizat...Selective catalytic reduction(SCR) denitration may increase the emission of NH4+and NH3.The removal and transformation characteristics of ammonium sulfate aerosols and ammonia slip during the wet flue gas desulfurization(WFGD) process, as well as the effect of desulfurization parameters, were investigated in an experimental system equipped with a simulated SCR flue gas generation system and a limestone-based WFGD system.The results indicate that the ammonium sulfate aerosols and ammonia slip in the flue gas from SCR can be partly removed by slurry scrubbing, while the entrainment and evaporation of desulfurization slurry with accumulated NH4+will generate new ammoniumcontaining particles and gaseous ammonia.The ammonium-containing particles formed by desulfurization are not only derived from the entrainment of slurry droplets, but also from the re-condensation of gaseous ammonia generated by slurry evaporation.Therefore,even if the concentration of NH4+in the desulfurization slurry is quite low, a high level of NH4+was still contained in the fine particles at the outlet of the scrubber.When the accumulated NH4+in the desulfurization slurry was high enough, the WFGD system promoted the conversion of NH3 to NH4+and increased the additional emission of primary NH4+aerosols.With the decline of the liquid/gas ratio and flue gas temperature, the removal efficiency of ammonia sulfate aerosols increased, and the NH4+emitted from entrainment and evaporation of the desulfurization slurry decreased.In addition, the volatile ammonia concentration after the WFGD system was reduced with the decrease of the NH4+concentration and p H values of the slurry.展开更多
Time delays in the feedback control often dete- riorate the control performance or even cause the instability of a dynamic system. This paper presents a control strategy for the dynamic system with a constant or a slo...Time delays in the feedback control often dete- riorate the control performance or even cause the instability of a dynamic system. This paper presents a control strategy for the dynamic system with a constant or a slowly time-varying input delay based on a transformation, which sire-plifies the time-delay system the relation is discussed for into a delay-free one. Firstly, two existing reduction-based linear quadratic controls. One is continuous and the other is discrete. By extending the relation, a new reduction-based control is then developed with a numerical algorithm presented for practical control implementation. The controller suggested by the proposed method has such a promising property that it can be used for the cases of different values of an input time delay without redesign of controller. This property provides the potential for stabilizing the dynamic system with a time-varying input delay. Consequently, the application of the proposed method to the dynamic system with a slowly time-varying delay is discussed. Finally, numerical simulations are given to show the efficacy and the applicability of the method.展开更多
The Routh and Whittaker methods of reduction for Lagrange system on time scales with nabla derivatives are studied.The equations of motion for Lagrange system on time scales are established, and their cyclic integrals...The Routh and Whittaker methods of reduction for Lagrange system on time scales with nabla derivatives are studied.The equations of motion for Lagrange system on time scales are established, and their cyclic integrals and generalized energy integrals are given. The Routh functions and Whittaker functions of Lagrange system are constructed, and the order of differential equations of motion for the system are reduced by using the cyclic integrals or the generalized energy integrals with nabla derivatives. The results show that the reduced Routh equations and Whittaker equations hold the form of Lagrnage equations with nabla derivatives. Finally, two examples are given to illustrate the application of the results.展开更多
Highways in mountainous areas are easy to be damaged by such natural disasters as debris flows and landslides and disaster reduction decision support system (DRDSS) is one of the important means to mitigate these disa...Highways in mountainous areas are easy to be damaged by such natural disasters as debris flows and landslides and disaster reduction decision support system (DRDSS) is one of the important means to mitigate these disasters. Guided by the theories and technologies of debris flow and landslide reduction and supported by geographical information system (GIS), remote sensing and database techniques, a DRDSS against debris flow and landslide along highways in mountainous areas has been established on the basis of such principles as pertinence, systematicness, effectiveness, easy to use, open and expandability. The system consists of database, disaster analysis models and decisions on reduction of debris flows and landslides, mainly functioning to zone disaster dangerous degree, analyze debris flow activity, simulate debris flow deposition and diffusion, analyze landslide stability, select optimal highway renovation scheme and plan disaster prevention and control engineering. This system has been applied successfully to the debris flow and landslide treatment works along Palongzangbu Section of Sichuan-Tibet Highway.展开更多
文摘No matter whether a system is operated manually or automatically controlled by computer, the system’s vulnerability always exists. Earthquake Disaster Reduction System (EDRS) belongs to the category of information system. According to the features of security for EDRS, the steps and the methods on how to build the EDRS security were analyzed. The EDRS security features, security strategies and security measures were also given through a distributed EDRS skeleton that has been applied. Because there was still no appointed and authoritative agency or organization to certify and test EDRS security in China, a national information technology security certification center was introduced and suggested for the certification of the EDRS security. Finally, several discussions and tendencies for the EDRS development were presented.
基金Sponsored by the National Project of Scientific and Technical Supporting Programs (Grant No. 2006BAC13B02)the Returned Study Overseas Foundation of Heilongjiang Province (Grant No. LC06C37)Institute of Engineering Mechanics, China Earthquake Administration Science Foundation (Grant No. 2006B04)
文摘Through investigation on the international development trend of earthquake disaster reduction system(EDRS)researches,a well finished Daqing Oilfield EDRS is introduced.Based on the PC System,redevelopment of the EDRS skeleton is well discussed,including the technical skeleton,function composition,structures of software and hardware,redevelopment languages,database,and remote linking and calling of analysis modules.Meanwhile,it is pointed out that extending and utilizing the function of remote sensing information on the basis of the current distributed EDRS skeleton will become another study direction of EDRS.
基金supported by Shanghai Municipal Natural Science Foundation(No.12ZR1434900)International Collabora-tion on Drugs and Diagnostics Innovation of Tropical Diseases in China(International S&T Cooperation 2010DFB73280)
文摘Stannous chloride dihydrate is used as an efficient catalyst in reductive cyclization of 2-nitro-5- substituted aniline Schiff base leading to stable 2,5-disubstitued benzimidazole derivatives in excellent yields with good purity. It provides a novel method of synthesis of 2,5-disubstitued benzimidazole under reductive system at room temperature.
文摘s: Vinous aromatic nitro compounds could be selectively and rapidly reduced to the corresponding amines in excellent yields by potassium borohydride - bismuth chloride/ethanol-water, a new and facile reductive system.
基金financially supported by the National Natural Science Foundation of China (No.52200055)the Natural Science Foundation of Jiangsu Province (No.BK20210483)+1 种基金China Postdoctoral Science Foundation (No.2022T150271)the Natural Science Research of Jiangsu Higher Education Institutions of China (No.23KJB610001)。
文摘Water scarcity is an escalating global crisis,posing a severe threat to populations worldwide.Consequently,exploring various materials to remove emerging contaminants from freshwater sources has garnered significant attention.In this regard,single-atom catalysis(SACs) has emerged as a catalyst of scientific progress in water purification and treatment methodologies during recent decades.SACs exhibit exceptional catalytic activity,selectivity and stability,due to their near-perfect atom utilization,highly unsaturated coordination environment and uniform reaction centers.However,a comprehensive and critical review encompassing the successful integration of SACs into water purification processes needs to be completed.This review aims to accentuate recent trends by presenting the synthesis,structure,and environment and energy application-relevant properties of SACs.The results show that a comprehensive and multi-perspective summary of the advantages of SACs in environmental remediation can have significant benefits,such as fast kinetics,costeffectiveness,selectivity.The oxidation and reduction processes of SACs and functional SACs materials in water purification were emphasized.Furthermore,the last section is devoted to the current research gaps and further perspectives on the application of SACs in water treatment,which are summarized and analyzed.
文摘Solid waste and air pollution are never ending environmental problems that can be partially solved by turning waste into useful bio-products. In this study, enzymatic solutions were developed by formulating enzymatic solutions from fish intestines and fruit peels. This aimed to help in biodegradation of organic solid wastes. Organic waste samples were treated with formulated enzymatic solutions for 7 days in aerated set-up for aerobic degradation. Biodegradability and odor of the waste samples were compared with commercial enzymatic solution. Determination of evolved carbon dioxide (CO2) using gravimetric analysis (GA) was used to determine the percent biodegradability, Dt, of organic solid waste and odor-ranking method was used to determine the odor intensity of the organic waste samples. The result showed that the weight loss and percentage biodegradability of organic waste sample treated with formulated enzymatic solution is comparable with that of the commercial enzymatic solution. In terms of odor intensity, waste treated with the product, formulated enzymatic solution (FES) is also comparable to the waste treated with commercial enzymatic solution. Thus, implying that the developed FES is as efficient as that of the commercial enzymatic solution. These significant results will be helpful to future researchers in providing ways on improving the degradation of organic solid waste and mitigating the increasing glitches on our environment. Enzyme kinetics, physical and chemical properties studies of the solution were recommended for future researchers to accurately determine the effectiveness of the formulated enzymatic solution in the degradation of organic solid waste.
基金supported by the National Natural Science Foundation of China(Nos.52170083,51808143)the Science and Technology Innovation Program of Hunan Province(No.2022RC1125)the Hunan Provincial Natural Science Foundation of China(No.2021JJ20007)。
文摘In this study,we present a self-driven photoelectrocatalytic(SD-PEC)system that effectively treats complex uranium-bearing wastewaters for both uranium recovery and organic matter decomposition while generating power.The system utilizes a titanium dioxide nanorod array(TNR)photoelectrode coupled with a silicon solar cell to optimize electron transport,while the cathode is composed of a carbon fiber coated with carboxylated carbon nanotubes(CCNT/CF),which efficiently reduce UO_(2)^(2+).The results demonstrate significant removal efficiency of uranium(complete removal in 25 min at a rate constant of~0.248 min^(-1)),as well as substantial degradation of organic impurities.Furthermore,the system generates sufficient power output to light an LED lamp and exhibits superior performance under various complex wastewater conditions,including simulated seawater and real uranium tailings wastewater.These findings underscore the potential of the SD-PEC system as a versatile approach for sustainable treatment and energy recovery of radioactive wastewater.The significance of this research extends to global environmental challenges,offering an innovative solution for managing radioactive wastewater while simultaneously contributing to renewable energy generation.
基金Nemzeti Kutatási Fejlesztésiés Innovációs Hivatal,Grant/Award Number:RRF-2.3.1-21-2022-00009Horizon 2020 Framework Programme,Grant/Award Number:862453。
文摘This study demonstrates the electrochemical reduction of carbon monoxide(COR)at high current densities in a zero-gap electrolyzer cell and cell stack.By systematically optimizing both the commercially available membrane electrode assembly components(including binder content and gas diffusion layer)and the operating conditions,we could perform COR at current densities up to 1.4 A cm^(-2)with a maximum C2+selectivity of 90%.We demonstrated the scale-up to a 3×100 cm^(2)electrolyzer stack that can sustain stable operation at 1 A cm^(-2)for several hours without significant performance decay and with a total C2+selectivity of~80%and an ethylene selectivity of~40%.We provide critical insights into the holistic optimization of key system parameters,without using special catalysts or surface additives,which can pave the way for scalable and industrially viable COR processes.
文摘Layered transition metal hydroxides show distinct advantages in separately co-catalyzing CO_(2)reduction and H_(2)O oxidation at the electron-accumulating and hole-accumulating sites of wrapped heterojunction photocatalysts,while concurrently preventing side reactions and photocorrosion on the semiconductor surface.Herein,Ni-Co bimetallic hydroxides with varying Ni/Co molar ratios(Ni_(x)Co_(1-x)(OH)_(2),x=1,0.75,0.5,0.25,and 0)were grown in situ on a model 2D/2D S-scheme heterojunction composed of Cu_(2)O nanosheets and Fe_(2)O_(3)nanoplates to form a series of Cu_(2)O/Fe_(2)O_(3)@Ni_(x)Co_(1-x)(OH)_(2)(CF@NiCo)photocatalysts.The combined experimental and theoretical investigation demonstrates that incorporating an appropriate amount of Co into Ni(OH)_(2)not only modulates the energy band structure of Ni_(x)Co_(1-x)(OH)_(2),balances the electron-and hole-trapping abilities of the bifunctional cocatalyst and maximizes the charge separation efficiency of the heterojunction,but also regulates the d-band center of Ni_(x)Co_(1-x)(OH)_(2),reinforcing the adsorption and activation of CO_(2)and H_(2)O on the cocatalyst surface and lowering the rate-limiting barriers in the CO_(2)-to-CO and H_(2)O-to-O_(2)conversion.Benefiting from the Ni-Co synergy,the redox reactions proceed stoichiometrically.The optimized CF@Ni_(0.75)Co_(0.25)achieves CO and O_(2)yields of 552.7 and 313.0μmol gcat^(-1)h^(-1),respectively,11.3/9.9,1.6/1.7,and 4.5/5.9-fold higher than those of CF,CF@Ni,and CF@Co.This study offers valuable insights into the design of bifunctional noble-metal-free cocatalysts for high-performance artificial photosynthesis.
基金supports from the National Natural Science Foundation of China(Grant Nos.12305372 and 22376217)the National Key Research&Development Program of China(Grant Nos.2022YFA1603802 and 2022YFB3504100)+1 种基金the projects of the key laboratory of advanced energy materials chemistry,ministry of education(Nankai University)key laboratory of Jiangxi Province for persistent pollutants prevention control and resource reuse(2023SSY02061)are gratefully acknowledged.
文摘Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespread attention for CO_(2)RR due to their high catalytic activity,selectivity,excellent stability,and low cost.However,they still need to be further improved to meet the needs of industrial applications.This review article comprehensively summarizes the recent advances in regulation strategies of Bi-based catalysts and can be divided into six categories:(1)defect engineering,(2)atomic doping engineering,(3)organic framework engineering,(4)inorganic heterojunction engineering,(5)crystal face engineering,and(6)alloying and polarization engineering.Meanwhile,the corresponding catalytic mechanisms of each regulation strategy will also be discussed in detail,aiming to enable researchers to understand the structure-property relationship of the improved Bibased catalysts fundamentally.Finally,the challenges and future opportunities of the Bi-based catalysts in the photoelectrocatalytic CO_(2)RR application field will also be featured from the perspectives of the(1)combination or synergy of multiple regulatory strategies,(2)revealing formation mechanism and realizing controllable synthesis,and(3)in situ multiscale investigation of activation pathways and uncovering the catalytic mechanisms.On the one hand,through the comparative analysis and mechanism explanation of the six major regulatory strategies,a multidimensional knowledge framework of the structure-activity relationship of Bi-based catalysts can be constructed for researchers,which not only deepens the atomic-level understanding of catalytic active sites,charge transport paths,and the adsorption behavior of intermediate products,but also provides theoretical guiding principles for the controllable design of new catalysts;on the other hand,the promising collaborative regulation strategies,controllable synthetic paths,and the in situ multiscale characterization techniques presented in this work provides a paradigm reference for shortening the research and development cycle of high-performance catalysts,conducive to facilitating the transition of photoelectrocatalytic CO_(2)RR technology from the laboratory routes to industrial application.
基金funded by National Natural Science Foundation of China(Nos.12402142,11832013 and 11572134)Natural Science Foundation of Hubei Province(No.2024AFB235)+1 种基金Hubei Provincial Department of Education Science and Technology Research Project(No.Q20221714)the Opening Foundation of Hubei Key Laboratory of Digital Textile Equipment(Nos.DTL2023019 and DTL2022012).
文摘Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when tackling high-dimensional optimization challenges.To effectively address these challenges,this study introduces cooperative metaheuristics integrating dynamic dimension reduction(DR).Building upon particle swarm optimization(PSO)and differential evolution(DE),the proposed cooperative methods C-PSO and C-DE are developed.In the proposed methods,the modified principal components analysis(PCA)is utilized to reduce the dimension of design variables,thereby decreasing computational costs.The dynamic DR strategy implements periodic execution of modified PCA after a fixed number of iterations,resulting in the important dimensions being dynamically identified.Compared with the static one,the dynamic DR strategy can achieve precise identification of important dimensions,thereby enabling accelerated convergence toward optimal solutions.Furthermore,the influence of cumulative contribution rate thresholds on optimization problems with different dimensions is investigated.Metaheuristic algorithms(PSO,DE)and cooperative metaheuristics(C-PSO,C-DE)are examined by 15 benchmark functions and two engineering design problems(speed reducer and composite pressure vessel).Comparative results demonstrate that the cooperative methods achieve significantly superior performance compared to standard methods in both solution accuracy and computational efficiency.Compared to standard metaheuristic algorithms,cooperative metaheuristics achieve a reduction in computational cost of at least 40%.The cooperative metaheuristics can be effectively used to tackle both high-dimensional unconstrained and constrained optimization problems.
基金Project(JS-211)supported by the State-Owned Enterprise Electric Vehicle Industry Alliance,China
文摘NA novel smelting reduction process based on FeO-SiO2-Al2O3 slag system for spent lithium ion batteries with Al cans was developed, while using copper slag as the only slag former. The feasibility of the process and the mechanism of copper loss in slag were investigated. 98.83% Co, 98.39% Ni and 93.57% Cu were recovered under the optimum conditions of slag former/battery mass ratio of 4.0：1, smelting temperature of 1723 K, and smelting mass ratio of time of 30 min. The FeO-SiO2-Al2O3 slag system for the smelting process is appropriate under the conditions of m（FeO）：m（SiO2）=0.58：1？1.03：1, and 17.19%？21.52% Al2O3 content. The obtained alloy was mainly composed of Fe-Co-Cu-Ni solid solution including small amounts of matte. The obtained slag mainly consisted of fayalite and hercynite. Meanwhile, the mechanism of copper loss is the mechanical entrainment from strip-like fayalite particles in the main form of copper sulfide and metallic copper.
基金Project (51074025) supported by the National Natural Science Foundation of ChinaProject (FRF-SD-12-009A) supported by the Fundamental Research Funds for the Central Universities,China
文摘The reduction behaviors and characteristics of products of the Fe-Cr-O system （FeCr2O4 and Fe2O3＋Cr2O3） and Fe-Cr-Ni-O system （Fe2O3＋Cr2O3＋NiO） under various conditions were studied. The results show that more Fe-Cr or Fe-Cr-Ni solution and less residual carbon content were obtained at higher temperatures and lower initial molar ratio of C to O （nC：nO）. The degree of reduction was highly dependent on both time and temperature, and the residual carbon content greatly increased with increasing nC：nO at each temperature. The products generated during the carbothermic reduction of the Fe-Cr-O system were examined using X-ray diffraction （XRD）. A scanning electron microscope （SEM） coupled with energy dispersive spectrometer was used to observe the microstructure and the distribution of elements in the various phases of the final reduction products of the Fe-Cr-O and Fe-Cr-Ni-O.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.61074052 and No.61072032）. Herschel Rabitz acknowledges the support from Army Research Office （ARO）.
文摘We explores Hamiltonian reduction in pulse-controlled finite-dimensional quantum systems with near-degenerate eigenstates. A quantum system with a non-degenerate ground state and several near-degenerate excited states is controlled by a short pulse, and the objective is to maximize the collective population on all excited states when we treat all of them as one level. Two cases of the systems are shown to be equivalent to effective two-level systems. When the pulse is weak, simple relations between the original systems and the reduced systems are obtained. When the pulse is strong, these relations are still available for pulses with only one frequency under the first-order approximation.
文摘Refer to the Hamiltonian system, first integrals of the Birkhoffian system can be found by using of the perfect differential method. Through these first integrals, the order of the Birkhoffian system can be reduced. Then according to the alternate of the coordinate, a kind of new partial differential operator was defined in order to hold the Birkhoff form. The result shows that the Birkhoffian system has generalized energy integrals and cyclic integrals. Furthermore, each integral can reduce the order of equations two degrees.
基金Supported by the National Natural Science Foundation of China(No.40971147/D010503)the China Postdoctoral Science Foundation(No.2013M542238)+1 种基金the Fundamental Research Funds for The Central Universities,China(No.XDJK2013C151)the Ph.D.Initiation Fund of Southwest University,China(No.SWU112098)
文摘As a global pollutant process, the reduction of mercury （Hg） is especially important. One pathway is through an abiotic reduction with humic acids （HAs）, which is controlled by different factors, including initial Hg and HA concentrations, pH, temperature and light. In this study, three humic acids were selected to illustrate the Hg2＋ abiotic reduction mechanisms by HAs, and to identify the key limiting factors for reduction rates and amounts. In addition, the initial status of the HAs as a solid or in an aqueous solution were also compared, to help explain why HAs show different dominant characteristics （e.g. complexation or reduction） in the reaction process with Hg. Results indicated that HAs were able to reduce Hg abiotically. Higher initial Hg, higher HA concentrations and either high （8.1） or low （3.6） solution pH decreased the HA reduction capacity. In addition, Hg~ production rates increased with increasing temperature, and the same trend was observed with light exposure. Humic acids added as an aqueous solution resulted in significantly greater HgO production than addition as a bulk solid. Finally, the Hg reduction rate and capacity varied significantly （P 〈 0.05） with HAs from different sources. These findings helped to explain why HAs showed different dominant characteristics （e.g. complexation or reduction） in the reaction process with of Hg2＋ reduction, which indicated that humic substances in sink or a source for Hg. Hg, and evidentially demonstrated the existence of a possible pathway natural environments, especially in water bodies, could act either as a
基金supported by the National Natural Science Foundation of China(Nos.51576039 and 51576039).
文摘Selective catalytic reduction(SCR) denitration may increase the emission of NH4+and NH3.The removal and transformation characteristics of ammonium sulfate aerosols and ammonia slip during the wet flue gas desulfurization(WFGD) process, as well as the effect of desulfurization parameters, were investigated in an experimental system equipped with a simulated SCR flue gas generation system and a limestone-based WFGD system.The results indicate that the ammonium sulfate aerosols and ammonia slip in the flue gas from SCR can be partly removed by slurry scrubbing, while the entrainment and evaporation of desulfurization slurry with accumulated NH4+will generate new ammoniumcontaining particles and gaseous ammonia.The ammonium-containing particles formed by desulfurization are not only derived from the entrainment of slurry droplets, but also from the re-condensation of gaseous ammonia generated by slurry evaporation.Therefore,even if the concentration of NH4+in the desulfurization slurry is quite low, a high level of NH4+was still contained in the fine particles at the outlet of the scrubber.When the accumulated NH4+in the desulfurization slurry was high enough, the WFGD system promoted the conversion of NH3 to NH4+and increased the additional emission of primary NH4+aerosols.With the decline of the liquid/gas ratio and flue gas temperature, the removal efficiency of ammonia sulfate aerosols increased, and the NH4+emitted from entrainment and evaporation of the desulfurization slurry decreased.In addition, the volatile ammonia concentration after the WFGD system was reduced with the decrease of the NH4+concentration and p H values of the slurry.
基金supported by the National Natural Science Foundation of China ( 10532050, 10702024 and 10702025) the Doctoral Fund of MOE of China (20070287029)
文摘Time delays in the feedback control often dete- riorate the control performance or even cause the instability of a dynamic system. This paper presents a control strategy for the dynamic system with a constant or a slowly time-varying input delay based on a transformation, which sire-plifies the time-delay system the relation is discussed for into a delay-free one. Firstly, two existing reduction-based linear quadratic controls. One is continuous and the other is discrete. By extending the relation, a new reduction-based control is then developed with a numerical algorithm presented for practical control implementation. The controller suggested by the proposed method has such a promising property that it can be used for the cases of different values of an input time delay without redesign of controller. This property provides the potential for stabilizing the dynamic system with a time-varying input delay. Consequently, the application of the proposed method to the dynamic system with a slowly time-varying delay is discussed. Finally, numerical simulations are given to show the efficacy and the applicability of the method.
基金supported by the National Natural Science Foundation of China(Grant Nos.11572212 and 11272227)the Innovation Program for Graduate Student of Jiangsu Province,China(Grant No.KYLX16-0414)
文摘The Routh and Whittaker methods of reduction for Lagrange system on time scales with nabla derivatives are studied.The equations of motion for Lagrange system on time scales are established, and their cyclic integrals and generalized energy integrals are given. The Routh functions and Whittaker functions of Lagrange system are constructed, and the order of differential equations of motion for the system are reduced by using the cyclic integrals or the generalized energy integrals with nabla derivatives. The results show that the reduced Routh equations and Whittaker equations hold the form of Lagrnage equations with nabla derivatives. Finally, two examples are given to illustrate the application of the results.
基金Supported by the Knowledge Innovation Program of Chinese Academy of Sciences(KZCX2-306)the National Natural Science Foundation of China(90202007)
文摘Highways in mountainous areas are easy to be damaged by such natural disasters as debris flows and landslides and disaster reduction decision support system (DRDSS) is one of the important means to mitigate these disasters. Guided by the theories and technologies of debris flow and landslide reduction and supported by geographical information system (GIS), remote sensing and database techniques, a DRDSS against debris flow and landslide along highways in mountainous areas has been established on the basis of such principles as pertinence, systematicness, effectiveness, easy to use, open and expandability. The system consists of database, disaster analysis models and decisions on reduction of debris flows and landslides, mainly functioning to zone disaster dangerous degree, analyze debris flow activity, simulate debris flow deposition and diffusion, analyze landslide stability, select optimal highway renovation scheme and plan disaster prevention and control engineering. This system has been applied successfully to the debris flow and landslide treatment works along Palongzangbu Section of Sichuan-Tibet Highway.
