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Correlation and pathways of behavioral activation systems mediating physical activity level and depressive symptoms among college students
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作者 Jiang-Hua Zhu Shu-Fan Li +4 位作者 Peng Wang Xin Xin Qun Zhao Si-Cheng Chen Xing Wang 《World Journal of Psychiatry》 SCIE 2023年第10期784-792,共9页
BACKGROUND Depression is a common mental disorder among college students.The main symptoms include being persistent low mood,sad emotional experiences,lack of pleasure,listlessness,and impaired cognitive function acco... BACKGROUND Depression is a common mental disorder among college students.The main symptoms include being persistent low mood,sad emotional experiences,lack of pleasure,listlessness,and impaired cognitive function accompanied by tendencies of self-harm and suicide.AIM To clarify the pathways and effects of the behavioral activation system between physical activity and depressive symptoms in college students with depressive symptoms.METHODS This cross-sectional research screened 3047 college students.Of these,472 had depressive symptoms,with a depression detection rate of 15.49%.Furthermore,442 college students with depressive symptoms were analyzed.A one-way analysis of variance and Pearson’s correlation,linear regression,and structural equation modeling analyses were used to explore the correlations and pathways of the interactions between the variables.RESULTS Depressive symptoms were significantly negatively correlated with physical activity(r=-0.175,P<0.001),the behavioral activation system(r=-0.197,P<0.001),and drive(r=-0.113,P=0.017).Furthermore,it was negatively correlated with fun-seeking(FS)(r=-0.055,P=0.251);however,it was not significant.Physical activity was significantly positively correlated with reward responsiveness(RR)(r=0.141,P=0.003)and drive(r=0.124,P=0.009)and not significantly positively correlated with FS(r=0.090,P=0.058).The mediating effect of RR between physical activity and depressive symptoms was significant[B=-0.025,95%confidence interval(95%CI):-0.051 to-0.008,P=0.001].The direct and total effects of physical activity on depressive symptoms and were significant(B=-0.150,95%CI:-0.233 to-0.073,P<0.001;B=-0.175,95%CI:-0.260 to-0.099,P<0.001),respectively.CONCLUSION As physical activity levels increased,depression scores among college students decreased.The mediating effect of RR between physical activity and depressive symptoms was significant.Therefore,colleges and universities should encourage college students with depression to increase their physical activity and improve their behavioral activation system.Particular attention should be paid to RR,which may reduce the prevalence of depressive symptoms. 展开更多
关键词 College students Physical activity Depressive symptoms Behavioral activation system Mediating role
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Inhibition in Action-Inhibitory Components in the Behavioral Activation System
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作者 Stefan Sutterlin Stein Andersson Claus Vogele 《Journal of Behavioral and Brain Science》 2011年第3期160-166,共7页
Over the past two decades, the neurobiological substrates of the reinforcement theory have been discussed in terms of a behavioral activation system (BAS) and a behavioral inhibition system (BIS). While the BAS has be... Over the past two decades, the neurobiological substrates of the reinforcement theory have been discussed in terms of a behavioral activation system (BAS) and a behavioral inhibition system (BIS). While the BAS has been conceptualized as both an activating system and an approach-related system, the empirical evidence for either approach remains inconclusive. In the current study we hypothesize that the inclusion of self-regulatory capacity contributes to a better understanding of the BAS. In a sample of 29 volunteers motor response inhibition elicited by a stop-signal task and heart rate variability (HRV) as a proxy of self-regulatory capacity were related to BAS scores (BIS/BAS scales [1]). Results show significant positive associations between inhibitory capacity and the sensitivity of the behavioral activation system, suggesting markers of self-regulation as components of the BAS. 展开更多
关键词 Behavioral activation system Heart Rate Variability Stop-Signal Task SELF-REGULATION
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Analysis of Environmental Endocrine Disrupting Activities in Wastewater Treatment Plant Effluents Using Recombinant Yeast Assays Incorporated with Exogenous Metabolic Activation System 被引量:2
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作者 LI Jian CHEN Ming +2 位作者 WANG ZiJian MA Mei PENG XianZhi 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第2期132-139,共8页
Objective To measure the endocrine disrupting chemicals (EDCs) in wastewater and evaluate the EDCs removal efficiencies in the municipal wastewater treatment plants (WWTP). Methods A battery of in vitro recombinan... Objective To measure the endocrine disrupting chemicals (EDCs) in wastewater and evaluate the EDCs removal efficiencies in the municipal wastewater treatment plants (WWTP). Methods A battery of in vitro recombinant yeast bioassays incorporated with exogenous metabolic activation system (rat liver preparation, S9 mix) was conducted to assess the estrogen receptor (ER), androgen receptor (AR), progesterone receptor (PR), and thyroid receptor (TR) ant/agonistic activities of effluents collected from Datansha WWTP. Results The indirect estrogenic, anti‐androgenic, anti‐progesteronic, and anti‐thyroidic activities were observed in the influent. The removal efficiencies of EDCs were above 74%, suggesting that the present wastewater treatment processes were good enough to remove most of these indirect endocrine disrupting chemicals. Conclusion The incorporation of exogenous metabolic capacity into the test system was valid for the study of indirect effects on ER, AR, PR, and TR. 展开更多
关键词 Recombinant yeast assay Endocrine disrupting chemicals Wastewater sample Metabolic activation
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Steadfast Energy Proficient Sensor Node Activation System in Wireless Networks Lifetime Enhancement
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作者 R. Saravanakumar Dr. N. Mohankumar 《Circuits and Systems》 2016年第4期402-416,共15页
The wireless sensor network (WSN) is one of the budding exploring areas and fast rising fields in wireless communications. The sensor nodes in the network are generally small-size, low-cost, low-power and multi-functi... The wireless sensor network (WSN) is one of the budding exploring areas and fast rising fields in wireless communications. The sensor nodes in the network are generally small-size, low-cost, low-power and multi-function capabilities. Wireless sensor networks (WSNs) are used for various applications;since numerous sensor nodes are usually deployed on remote and inaccessible places, the employment and preservation should be easy and scalable. Sensor nodes in the field being run out of energy quickly has been an issue and many energy efficient routing protocols have been proposed to solve this problem and preserve the long life of the network. This paper work proposes a hierarchical based node activation routing technique which shows energy efficiency. This technique selects cluster head with highest residual energy in each communication round of transmission to the base station from the cluster heads. Hierarchical based node activation routing technique with different levels of hierarchy simulation results prolongs the lifetime of the network compared to other clustering schemes and communication rounds of simulation increase significantly. 展开更多
关键词 Wireless Sensor Networks Hierarchical Routing Energy Efficiency CLUSTERING Node activation Scheme Network Lifespan
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Macrophage Activation Syndrome as the Primary Presentation of Pediatric Systemic Lupus Erythematosus: A Case Report and Review of the Literature
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作者 Hanane Hajaj Hanae Bahari +3 位作者 Aziza El Ouali Ayyad Ghanam Maria Rkain Abdeladim Babakhouya 《Open Journal of Pediatrics》 2024年第1期132-138,共7页
Macrophage activation syndrome (MAS), in its secondary form, often complicates rheumatic diseases but rarely constitutes a mode of revelation. Systemic lupus erythematosus (SLE) is a systemic autoimmune disease of unk... Macrophage activation syndrome (MAS), in its secondary form, often complicates rheumatic diseases but rarely constitutes a mode of revelation. Systemic lupus erythematosus (SLE) is a systemic autoimmune disease of unknown etiology that primarily affects women in adulthood. MAS is a serious condition that may be the first presentation of SLE. Here, we report the case of a 4-year-old female with MAS as the primary manifestation of Systemic Lupus Erythematosus (SLE). In this case, we outline the characteristics of a complex case of SLE that was initially accompanied with MAS, and also review the literature to discuss the clinical, biological, and therapeutic aspects of this condition. 展开更多
关键词 Macrophage activation Syndrome systemic Lupus Erythematosus CHILD
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Association between physical activity and risk of gastroesophageal reflux disease:A systematic review and meta-analysis 被引量:2
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作者 Chuting Yu Tinglu Wang +7 位作者 Ye Gao Yunfei Jiao Huishan Jiang Yan Bian Wei Wang Han Lin Lei Xin Luowei Wang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第5期687-698,共12页
Background:Lifestyle plays an important role in preventing and managing gastroesophageal reflux disease(GERD).In response to the conflicting results in previous studies,we performed a systematic review and meta-analys... Background:Lifestyle plays an important role in preventing and managing gastroesophageal reflux disease(GERD).In response to the conflicting results in previous studies,we performed a systematic review and meta-analysis to investigate this association.Methods:Relevant studies published until January 2023 were retrieved from 6 databases,and the prevalence of symptomatic gastroesophageal reflux(GER)or GERD was determined from the original studies.A random effects model was employed to meta-analyze the association by computing the pooled relative risk(RR)with 95%confidence intervals(95%CIs).Furthermore,subgroup and dose-response analyses were performed to explore subgroup differences and the association between cumulative physical activity(PA)time and GERD.Results:This meta-analysis included 33 studies comprising 242,850 participants.A significant negative association was observed between PA and the prevalence of symptomatic GER(RR=0.74,95%CI:0.66-0.83;p<0.01)or GERD(RR=0.80,95%CI:0.76-0.84;p<0.01),suggesting that engaging in PA might confer a protective benefit against GERD.Subgroup analyses consistently indicated the presence of this association across nearly all subgroups,particularly among the older individuals(RR_(<40 years):RR_(≥40 years)=0.85:0.69,p<0.01)and smokers(RR_(smoker):RR_(non-smoker)=0.67:0.82,p=0.03).Furthermore,a dose-response analysis revealed that individuals who engaged in 150 min of PA per week had a 72.09%lower risk of developing GERD.Conclusion:Maintaining high levels of PA decreased the risk of GERD,particularly among older adults and smokers.Meeting the recommended PA level of 150 min per week may significantly decrease the prevalence of GERD. 展开更多
关键词 Physical activity Gastroesophageal reflux disease PREVALENCE systematic review
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Alexa,let's train now!——A systematic review and classification approach to digital and home-based physical training interventions aiming to support healthy cognitive aging 被引量:1
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作者 Fabian Herold Paula Theobald +5 位作者 Thomas Gronwald Navin Kaushal Liye Zou Eling D.de Bruin Louis Bherer Notger GMüller 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期30-46,共17页
Background:There is mounting evidence that regular physical activity is an important prerequisite for healthy cognitive aging.Consequently,the finding that almost one-third of the adult population does not reach the r... Background:There is mounting evidence that regular physical activity is an important prerequisite for healthy cognitive aging.Consequently,the finding that almost one-third of the adult population does not reach the recommended level of regular physical activity calls for further public health actions.In this context,digital and home-based physical training interventions might be a promising alternative to center-based intervention programs.Thus,this systematic review aimed to summarize the current state of the literature on the effects of digital and home-based physical training interventions on adult cognitive performance.Methods:In this pre-registered systematic review(PROSPERO;ID:CRD42022320031),5 electronic databases(PubMed,Web of Science,Psyclnfo,SPORTDiscus,and Cochrane Library)were searched by 2 independent researchers(FH and PT)to identify eligible studies investigating the effects of digital and home-based physical training interventions on cognitive performance in adults.The systematic literature search yielded 8258 records(extra17 records from other sources),of which 27 controlled trials were considered relevant.Two reviewers(FH and PT)independently extracted data and assessed the risk of bias using a modified version of the Tool for the assEssment of Study qualiTy and reporting in EXercise(TESTEX scale).Results:Of the 27 reviewed studies,15 reported positive effects on cognitive and motor-cognitive outcomes(i.e.,performance improvements in measures of executive functions,working memory,and choice stepping reaction test),and a considerable heterogeneity concerning study-related,population-related,and intervention-related characteristics was noticed.A more detailed analysis suggests that,in particular,interventions using online classes and technology-based exercise devices(i.e.,step-based exergames)can improve cognitive performance in healthy older adults.Approximately one-half of the reviewed studies were rated as having a high risk of bias with respect to completion adherence(≤85%)and monitoring of the level of regular physical activity in the control group.Conclusion:The current state of evidence concerning the effectiveness of digital and home-based physical training interventions is mixed overall,though there is limited evidence that specific types of digital and home-based physical training interventions(e.g.,online classes and step-based exergames)can be an effective strategy for improving cognitive performance in older adults.However,due to the limited number of available studies,future high-quality studies are needed to buttress this assumption empirically and to allow for more solid and nuanced conclusions. 展开更多
关键词 Brain COGNITION Digital health Exercise-cognition Physical activity
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The Role of Trait Activation Theory in Occupational Behavior:A Systematic Review
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作者 Paraskevi Tasoula Michael Galanakis 《Psychology Research》 2023年第2期83-87,共5页
The Trait Activation Theory(TAT)is widely regarded as the most influential personality theory approach in psychology.The purpose of this study is to analyze the TAT’s role in the contemporary workplace.Which personal... The Trait Activation Theory(TAT)is widely regarded as the most influential personality theory approach in psychology.The purpose of this study is to analyze the TAT’s role in the contemporary workplace.Which personality traits are more likely to predict work success?Which characteristics should businesses prioritize throughout the recruiting and selection processes?According to the Trait Activation Theory,what is the significance of motivation in the workplace and how can employers find employees who can be more productive,efficient,and involved in the organization’s goals?A systematic review of past recent research was used to answer the questions raised above.Following the gathering and examination of multiple recent publications on the issue,it was determined that the use of this model had a favorable impact on individual and group performance,working relationships,manager job performance,and workplace creativity. 展开更多
关键词 Trait activation Theory Big Five Theory WORKPLACE personality traits work behavior job performance leadership group innovation core self-evaluation autonomy
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Experimental study on the activation of coal gasification fly ash from industrial CFB gasifiers
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作者 Qiyao Yang Xiaobin Qi +1 位作者 Qinggang Lyu Zhiping Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期8-18,共11页
Coal gasification fly ash(CGFA)is an industrial solid waste from the coal circulating fluidized bed(CFB)gasification process,and it needs to be effectively disposed to achieve sustainable development of the environmen... Coal gasification fly ash(CGFA)is an industrial solid waste from the coal circulating fluidized bed(CFB)gasification process,and it needs to be effectively disposed to achieve sustainable development of the environment.To realize the application of CGFA as a precursor of porous carbon materials,the physicochemical properties of three kinds of CGFA from industrial CFB gasifiers are analyzed.Then,the activation potential of CGFA is acquired via steam activation experiments in a tube furnace reactor.Finally,the fluidization activation technology of CGFA is practiced in a bench-scale CFB test rig,and its advantages are highlighted.The results show that CGFA is characterized by a high carbon content in the range of 54.06%–74.09%,an ultrafine particle size(d50:16.3–26.1 μm),and a relatively developed pore structure(specific surface area SSA:139.29–551.97 m^(2)·g^(-1)).The proportion of micropores in CGFA increases gradually with the coal rank.Steam activation experiments show that the pore development of CGFA mainly includes three stages:initial pore development,dynamic equilibrium between micropores and mesopores and pore collapse.The SSA of lignite fly ash(LFA),subbituminous fly ash(SBFA)and anthracite fly ash(AFA)is maximally increased by 105%,13%and 72%after steam activation;the order of the largest carbon reaction rate and decomposition ratio of steam among the three kinds of CGFA is SBFA>LFA>AFA.As the ratio of oxygen to carbon during the fluidization activation of LFA is from 0.09 to 0.19,the carbon conversion ratio increases from 14.4%to 26.8%and the cold gas efficiency increases from 6.8%to 10.2%.The SSA of LFA increases by up to 53.9%during the fluidization activation process,which is mainly due to the mesoporous development.Relative to steam activation in a tube furnace reactor,fluidization activation takes an extremely short time(seconds)to achieve the same activation effect.It is expected to further improve the activation effect of LFA by regulating the carbon conversion ratio range of 27%–35%to create pores in the initial development stage. 展开更多
关键词 Circulating fluidized bed Coal gasification fly ash Steam activation Pore structure evolution Fluidization activation
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Acid mine drainage activation mechanism on lime-depressed pyrite flotation from copper sulfide ore
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作者 Jia-qiao YUAN Zhan DING +3 位作者 Yun-xiao BI Jie LI Shu-ming WEN Shao-jun BAI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2987-3001,共15页
The lime-depressed pyrite from Cu differential flotation tailings with acid mine drainage(AMD)as a natural activator was recovered.The effect of AMD on lime-depressed pyrite flotation was investigated by a series of l... The lime-depressed pyrite from Cu differential flotation tailings with acid mine drainage(AMD)as a natural activator was recovered.The effect of AMD on lime-depressed pyrite flotation was investigated by a series of laboratory flotation tests and surface analytical techniques.Flotation test results indicated that AMD could effectively activate the pyrite flotation with a sodium butyl xanthate(SBX)collector,and a high-quality sulfur concentrate was obtained.Pulp ion concentration analysis results indicated that AMD facilitated desorption of Ca^(2+)and adsorption of Cu^(2+)on the depressed-pyrite surface.Adsorption measurements and contact angle analysis results confirmed that adding AMD improved the adsorption amount of SBX collector on the pyrite surface and increased the contact angle by 31°.Results of Raman spectroscopy and X-ray photoelectron spectroscopy analysis indicated that AMD treatment promoted the formation of hydrophobic species(S^(0) hydrophobic entity and copper sulfides)and the removal of hydrophilic calcium and iron species on the pyrite surface,which reinforced the adsorption of collector.The findings of the present research provide important theoretical basis and technical support for a cleaner production of copper sulfide ores. 展开更多
关键词 copper sulfur ore acid mine drainage lime-depressed pyrite FLOTATION natural activator activation mechanism
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Strategies to achieve effective nitrogen activation
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作者 Bin Chang Huabin Zhang +1 位作者 Shuhui Sun Gaixia Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期137-163,共27页
Ammonia serves as a crucial chemical raw material and hydrogen energy carrier.Aqueous electrocatalytic nitrogen reduction reaction(NRR),powered by renewable energy,has attracted tremendous interest during the past few... Ammonia serves as a crucial chemical raw material and hydrogen energy carrier.Aqueous electrocatalytic nitrogen reduction reaction(NRR),powered by renewable energy,has attracted tremendous interest during the past few years.Although some achievements have been revealed in aqueous NRR,significant challenges have also been identified.The activity and selectivity are fundamentally limited by nitrogen activation and competitive hydrogen evolution.This review focuses on the hurdles of nitrogen activation and delves into complementary strategies,including materials design and system optimization(reactor,electrolyte,and mediator).Then,it introduces advanced interdisciplinary technologies that have recently emerged for nitrogen activation using high-energy physics such as plasma and triboelectrification.With a better understanding of the corresponding reaction mechanisms in the coming years,these technologies have the potential to be extended in further applications.This review provides further insight into the reaction mechanisms of selectivity and stability of different reaction systems.We then recommend a rigorous and detailed protocol for investigating NRR performance and also highlight several potential research directions in this exciting field,coupling with advanced interdisciplinary applications,in situ/operando characterizations,and theoretical calculations. 展开更多
关键词 activation via mediators catalyst optimization electrochemical nitrogen fixation high-energy activation of nitrogen NITROGEN
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Thermal pretreatment of willow branches impacts yield and pore development of activated carbon in subsequent activation with ZnCl_(2) via modifying cellulose structure
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作者 Linghui Kong Chao Li +7 位作者 Runxing Sun Shu Zhang Yi Wang Jun Xiang Song Hu Dong Wang Chuanjun Leng Xun Hu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期227-237,共11页
Development of pore structures of activated carbon(AC)from activation of biomass with ZnCl_(2) relies on content and structure of cellulose/hemicellulose in the feedstock.Thermal pretreatment of biomass could induce d... Development of pore structures of activated carbon(AC)from activation of biomass with ZnCl_(2) relies on content and structure of cellulose/hemicellulose in the feedstock.Thermal pretreatment of biomass could induce dehydration and/or aromatization to change the structure of cellulose/hemicellulose.This might interfere with evolution of structures of AC,which was investigated herein via thermal pretreatment of willow branch(WB)from 200 to 360℃and the subsequent activation with ZnCl_(2) at 550℃.The results showed that thermal pretreatment at 360℃(WB-360)could lead to substantial pyrolysis to form biochar,with a yield of 31.9%,accompanying with nearly complete destruction of cellulose crystals and remarkably enhanced aromatic degree.However,cellulose residual in WB-360 could still be activated to form AC-360 with specific surface area of 1837.9 m~2·g^(-1),which was lower than that in AC from activation of untreated WB(AC-blank,2077.8 m~2·g^(-1)).Nonetheless,the AC-200 from activation of WB-200 had more developed pores(2113.9 m~2·g^(-1))and superior capability for adsorption of phenol,due to increased permeability of ZnCl_(2) to the largely intact cellulose structure in WB-200.The thermal pretreatment did increase diameters of micropores of AC but reduced the overall yield of AC(26.8%for AC-blank versus 18.0%for AC-360),resulting from accelerated cracking but reduced intensity of condensation.In-situ infrared characterization of the activation showed that ZnCl_(2) mainly catalyzed dehydration,dehydrogenation,condensation,and aromatization but not cracking,suppressing the formation of derivatives of cellulose and lignin in bio-oil.The thermal pretreatment formed phenolic-OH and C=O with higher chemical innerness,which changed the reaction network in activation,shifting morphology of fibrous structures in AC-blank to“melting surface”in AC-200 or AC-280. 展开更多
关键词 Thermal pretreatment activation with ZnCl_(2) Willow branch Activated carbon Biochar
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Mechanistic insights into stepwise activation of malachite for enhancing surface reactivity and flotation performance
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作者 Qicheng Feng Wanming Lu +1 位作者 Han Wang Qian Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2159-2172,共14页
Malachite is a common copper oxide mineral that is often enriched using the sulfidization-xanthate flotation method.Currently,the direct sulfidization method cannot yield copper concentrate products.Therefore,a new su... Malachite is a common copper oxide mineral that is often enriched using the sulfidization-xanthate flotation method.Currently,the direct sulfidization method cannot yield copper concentrate products.Therefore,a new sulfidization flotation process was developed to promote the efficient recovery of malachite.In this study,Cu^(2+) was used as an activator to interact with the sample surface and increase its reaction sites,thereby strengthening the mineral sulfidization process and reactivity.Compared to single copper ion activation,the flota-tion effect of malachite significantly increased after stepwise Cu^(2+) activation.Zeta potential,X-ray photoelectron spectroscopy(XPS),time-of-flight secondary ion mass spectroscopy(ToF-SIMS),scanning electron microscopy and energy dispersive spectrometry(SEM-EDS),and atomic force microscopy(AFM)analysis results indicated that the adsorption of S species was significantly enhanced on the mineral surface due to the increase in active Cu sites after Cu^(2+) stepwise activation.Meanwhile,the proportion of active Cu-S spe-cies also increased,further improving the reaction between the sample surface and subsequent collectors.Fourier-transform infrared spec-troscopy(FT-IR)and contact angle tests implied that the xanthate species were easily and stably adsorbed onto the mineral surface after Cu^(2+) stepwise activation,thereby improving the hydrophobicity of the mineral surface.Therefore,the copper sites on the malachite sur-face after Cu^(2+) stepwise activation promote the reactivity of the mineral surface and enhance sulfidization flotation of malachite. 展开更多
关键词 MALACHITE copper ions stepwise activation flotation mechanism enhanced sulfidization
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Fabrication of pollution-free coal gangue-based catalytic material utilizing ferrous chloride as activator for efficient peroxymonosulfate activation
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作者 Zhiming Sun Xinlin Wang +3 位作者 Shaoran Jia Jialin Liang Xiaotian Ning Chunquan Li 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期103-118,共16页
Novel coal gangue-based persulfate catalyst(CG-FeCl_(2))was successfully synthesized by the means of calcinating under nitrogen atmosphere with the addition of ferrous chloride tetrahydrate(FeCl_(2)·_(4)H_(2)O).T... Novel coal gangue-based persulfate catalyst(CG-FeCl_(2))was successfully synthesized by the means of calcinating under nitrogen atmosphere with the addition of ferrous chloride tetrahydrate(FeCl_(2)·_(4)H_(2)O).The phase transformation of the prepared materials and gas products during the heating process are thoroughly investigated.It is suggested that ferrous chloride participated in the phase transformation and formed Si-O-Fe bonds.And the main gaseous products are H_(2)O,H_(2),and HCl during the heating process.Besides,the ability of CG-FeCl_(2) to activate peroxymonosulfate(PMS)for catalytic degradation of polycyclic aromatic hydrocarbons(PAHs)and phenol was deeply studied.More than 95%of naphthyl,phenanthrene and phenol were removed under optimizied conditions.In addition,1O_(2),·OH,and SO_(4)·−were involved in the CG-FeCl_(2)/PMS system from the free radical scavenging experiment,where 1O_(2) played a major role during the oxidation process.Furthermore,CG-FeCl_(2)/PMS system exhibited superior stability in a relatively wide pH range and the presence of common anion from related degradation experiments.Overall,the novel CG-FeCl_(2) is an efficient and environmentally friendly catalyst,displaying potential application prospect in the field of PAHs and phenol-contaminated wastewater treatment. 展开更多
关键词 Coal gangue Persulfate activation Advanced oxidation processes Polycyclic aromatic hydrocarbons Phenol Ferrous chloride
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Zonal activation of molecular carbon dioxide and hydrogen over dual sites Ni-Co-MgO catalyst for CO_(2) methanation:Synergistic catalysis of Ni and Co species
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作者 Zonglin Li Jianjun Chen +8 位作者 Yu Xie Junjie Wen Huiling Weng Mingxue Wang Jingyi Zhang Jinyan Cao Guocai Tian Qiulin Zhang Ping Ning 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期213-225,共13页
An in-depth mechanism in zonal activation of CO_(2)and H2molecular over dual-active sites has not been revealed yet.Here,Ni-Co-MgO was rationally constructed to elucidate the CO_(2)methanation mechanism.The abundant s... An in-depth mechanism in zonal activation of CO_(2)and H2molecular over dual-active sites has not been revealed yet.Here,Ni-Co-MgO was rationally constructed to elucidate the CO_(2)methanation mechanism.The abundant surface nickel and cobalt components as active sites led to strong Ni-Co interaction with charge transfer from nickel to cobalt.Notably,electron-enriched Coδ-species participated in efficient chemisorption and activation of CO_(2)to generate monodentate carbonate.Simultaneously,plentiful available Ni0sites facilitated H2dissociation,thus CO_(2)and H2were smoothly activated at zones of Coδ-species and Ni0,respectively.Detailed in situ DRIFTS,quasi situ XPS,TPSR,and DFT calculations substantiated a new formate evolution mechanism via monodentate carbonate instead of traditional bidentate carbonate based on synergistic catalysis of Coδ-species and Ni0.The zonal activation of CO_(2)and H2by tuning electron behaviors of double-center catalysts can boost heterogeneous catalytic hydrogenation performance. 展开更多
关键词 Zonal activation CO_(2) methanation Dual active sites Synergistic effect
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Study of the reaction mechanism for preparing powdered activated coke with SO_(2)adsorption capability via one-step rapid activation method under flue gas atmosphere
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作者 Binxuan Zhou Jingcai Chang +5 位作者 Jun Li Jinglan Hong Tao Wang Liqiang Zhang Ping Zhou Chunyuan Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期158-168,共11页
In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction m... In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction mechanism is summarized.Results indicate that the reaction process of this method can be divided into three stages:stage I is the rapid release of volatiles and the rapid consumption of O_(2),primarily occurring within a reaction time range of 0-0.5 s;stage II is mainly the continuous release and diffusion of volatiles,which is the carbonization and activation coupling reaction stage,and the carbonization process is the main in this stage.This stage mainly occurs at the reaction time range of 0.5 -2.0 s when SL-coal is used as material,and that is 0.5-3.0 s when JJ-coal is used as material;stage III is mainly the activation stage,during which activated components diffuse to both the surface and interior of particles.This stage mainly involves the reaction stage of CO_(2)and H2O(g)activation,and it mainly occurs at the reaction time range of 2.0-4.0 s when SL-coal is used as material,and that is 3.0-4.0 s when JJ-coal is used as material.Besides,the main function of the first two stages is to provide more diffusion channels and contact surfaces/activation sites for the diffusion and activation of the activated components in the third stage.Mastering the reaction mechanism would serve as a crucial reference and foundation for designing the structure,size of the reactor,and optimal positioning of the activator nozzle in PAC preparation. 展开更多
关键词 Reaction mechanism Powdered activated coke preparation SO_(2)adsorption One-step rapid activation Flue gas atmosphere
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Activation Distance and Capacity Analysis for Ambient Backscatter Communications with Sensitivity Constraint and Beamforming
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作者 Mu Yunping Fan Dian +2 位作者 Wang Gongpu Xu Yongjun Kuang Lei 《China Communications》 SCIE CSCD 2024年第11期257-266,共10页
Circuit sensitivity of sensors or tags without battery is one practical constraint for ambient backscatter communication systems.This letter considers using beamforming to reduce the sensitivity constraint and evaluat... Circuit sensitivity of sensors or tags without battery is one practical constraint for ambient backscatter communication systems.This letter considers using beamforming to reduce the sensitivity constraint and evaluates the corresponding performance in terms of the tag activation distance and the system capacity.Specifically,we derive the activation probabilities of the tag in the case of single-antenna and multi-antenna transmitters.Besides,we obtain the capacity expressions for the ambient backscatter communication system with beamforming and illustrate the power allocation that maximizes the system capacity when the tag is activated.Finally,simulation results are provided to corroborate our proposed studies. 展开更多
关键词 activation distance ambient backscatter communications beamforming channel capacity power allocation sensitivity
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Description of martensitic transformation kinetics in Fe-C-X(X = Ni,Cr,Mn,Si) system by a modified model
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作者 Xiyuan Geng Hongcan Chen +3 位作者 Jingjing Wang Yu Zhang Qun Luo Qian Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1026-1036,共11页
Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformat... Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformation during the cooling process must be addressed.At present,frequently used semi-empirical kinetics models suffer from huge errors at the beginning of transformation,and most of them fail to exhibit the sigmoidal shape characteristic of transformation curves.To describe the martensitic transformation process accurately,based on the Magee model,we introduced the changes in the nucleation activation energy of martensite with temperature,which led to the varying nucleation rates of this model during martensitic transformation.According to the calculation results,the relative error of the modified model for the martensitic transformation kinetics curves of Fe-C-X(X = Ni,Cr,Mn,Si) alloys reached 9.5% compared with those measured via the thermal expansion method.The relative error was approximately reduced by two-thirds compared with that of the Magee model.The incorporation of nucleation activation energy into the kinetics model contributes to the improvement of its precision. 展开更多
关键词 Fe-C-X system martensitic transformation kinetics curve semi-empirical model nucleation activation energy
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Revealing the correlation between adsorption energy and activation energy to predict the catalytic activity of metal oxides for HMX using DFT
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作者 Xiurong Yang Chi Zhang +6 位作者 Wujing Jin Zhaoqi Guo Hongxu Gao Shiyao Niu Fengqi Zhao Bo Liu Haixia Ma 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期262-270,共9页
Traditional selection of combustion catalysis is time-consuming and labor-intensive.Theoretical calculation is expected to resolve this problem.The adsorption energy of HMX and O atoms on 13 metal oxides was calculate... Traditional selection of combustion catalysis is time-consuming and labor-intensive.Theoretical calculation is expected to resolve this problem.The adsorption energy of HMX and O atoms on 13 metal oxides was calculated using DMol3,since HMX and O are key substances in decomposition process.And the relationship between the adsorption energy of HMX,O on metal oxides(TiO_(2),Al_(2)O_(3),PbO,CuO,Fe_(2)O_(3),Co_(3)O_(4),Bi_(2)O_(3),NiO)and experimental T30 values(time required for the decomposition depth of HMX to reach 30%)was depicted as volcano plot.Thus,the T30 values of other metal oxides was predicted based on their adsorption energy on volcano plot and validated by previous experimental data.Further,the adsorption energy of HMX on ZrO_(2)and MnO_(2)was predicted based on the linear relationship between surface energy and adsorption energy,and T30 values were estimated based on volcano plot.The apparent activation energy data of HMX/MgO,HMX/SnO_(2),HMX/ZrO_(2),and HMX/MnO_(2)obtained from DSC experiments are basically consistent with our predicted T30 values,indicating that it is feasible to predict the catalytic activity based on the adsorption calculation,and it is expected that these simple structural properties can predict adsorption energy to reduce the large quantities of computation and experiment cost. 展开更多
关键词 Density functional theory HMX Metal oxides Adsorption energy activation energy
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Screening the optimal Co_(x)/CeO_(2)(110)(x=1–6)catalyst for methane activation in coalbed gas
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作者 Li’nan Huang Danyang Li +3 位作者 Lei Jiang Zhiqiang Li Dong Tian Kongzhai Li 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期256-271,共16页
The challenges posed by energy and environmental issues have forced mankind to explore and utilize unconventional energy sources.It is imperative to convert the abundant coalbed gas(CBG)into high value-added products,... The challenges posed by energy and environmental issues have forced mankind to explore and utilize unconventional energy sources.It is imperative to convert the abundant coalbed gas(CBG)into high value-added products,i.e.,selective and efficient conversion of methane from CBG.Methane activation,known as the“holy grail”,poses a challenge to the design and development of catalysts.The structural complexity of the active metal on the carrier is of particular concern.In this work,we have studied the nucleation growth of small Co clusters(up to Co_(6))on the surface of CeO_(2)(110)using density functional theory,from which a stable loaded Co/CeO_(2)(110)structure was selected to investigate the methane activation mechanism.Despite the relatively small size of the selected Co clusters,the obtained Co_(x)/CeO_(2)(110)exhibits interesting properties.The optimized Co_(5)/CeO_(2)(110)structure was selected as the optimal structure to study the activation mechanism of methane due to its competitive electronic structure,adsorption energy and binding energy.The energy barriers for the stepwise dissociation of methane to form CH3^(*),CH2^(*),CH^(*),and C^(*)radical fragments are 0.44,0.55,0.31,and 1.20 eV,respectively,indicating that CH^(*)dissociative dehydrogenation is the rate-determining step for the system under investigation here.This fundamental study of metal-support interactions based on Co growth on the CeO_(2)(110)surface contributes to the understanding of the essence of Co/CeO_(2) catalysts with promising catalytic behavior.It provides theoretical guidance for better designing the optimal Co/CeO_(2) catalyst for tailored catalytic reactions. 展开更多
关键词 Co cluster growth Ce-based catalysts Methane activation DFT
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