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Global Radicalization and the San Bernardino Attack―Evolving Extremist U.S.Domestic Threat
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作者 Thomas M.Fitzpatrick 《International Relations and Diplomacy》 2018年第9期500-506,共7页
The focus of this paper is the process of radicalization of the San Bernardino attackers and their source of inspiration and affiliations.The literature on the pathway to terrorism and jihad appears to agree that path... The focus of this paper is the process of radicalization of the San Bernardino attackers and their source of inspiration and affiliations.The literature on the pathway to terrorism and jihad appears to agree that pathways and triggers are varied and many with no clear set of traits that one can identify to predict individual paths to jihadism,in short,it is an idiosyncratic process.So,while the psychological profiling of high risk jihadist individuals has yet to be fruitful,the psycho/sociological behaviors associated with jihadism appear to offer greater promise.This paper will divide into four actions:their pathway to radicalization,affiliations/relations,source of inspiration,and the conclusion. 展开更多
关键词 SAN Bernadino ATTACK ISLAMIC TERRORISM JIHAD radicalization
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Mobilization and Radicalization Through Persuasion: Manipulative Techniques in ISIS' Propaganda
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作者 Noemi M. Rocca 《International Relations and Diplomacy》 2017年第11期660-670,共11页
This paper explores the recent findings of some empirical research concerning Islamic State of Iraq and al-Sham's (ISIS') communication and tries to synthesize them under the theoretical frame of propaganda's con... This paper explores the recent findings of some empirical research concerning Islamic State of Iraq and al-Sham's (ISIS') communication and tries to synthesize them under the theoretical frame of propaganda's concept and practices. Many authors demonstrated how ISIS propaganda campaigns, in particular those deployed on cyberspace, proved to be effective in recruiting new members in both western and Muslim countries. However, while most of the researches focused on ISIS's communication contents and narratives, few works considered other methods and techniques used for actually delivering them. This is a regrettable missing point given the fact that communication's and neurosciences' studies demonstrate that not only what is communicated but also the techniques adopted bear important consequences on the receiver's perceptions and behavior. Therefore, this article analyzes in particular the findings of researches carried out by communication scholars, social psychologists, and neuro-cognitive scientists on ISIS' persuasive communication techniques and demonstrates their importance for security studies' analysis of ISIS' propaganda. It argues that ISIS' success in mobilizing people and make them prone to violent action relies on-among other factors-its knowledge and exploitation of sophisticated methods of perceptions' manipulation and behavior's influence. This, in turn, demonstrates ISIS' possession of state-like soft power capabilities effectively deployed in propaganda campaigns and therefore calls for a more complex understanding of its agency. 展开更多
关键词 ISIS propaganda soft power persuasive communication radicalization
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Second-Generation Muslim Youth Between Perception and Change: A Case Study on the Prevention of Radicalization
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作者 Marilena Macaluso Giuseppina Tumminelli +1 位作者 Angelica Spampinato Andrea Volterrani 《Sociology Study》 2020年第3期103-122,共20页
The following article presents the results of a research-action and an online communication campaign on the prevention of radicalization of second-generation young Italian Muslims as a part of a project called“Oltre... The following article presents the results of a research-action and an online communication campaign on the prevention of radicalization of second-generation young Italian Muslims as a part of a project called“Oltre”(the Italian acronym means“Beyond”)financed by European Union.After a short presentation of the four steps of the prevention communication model PKIC,a deepening on the radicalization factors,and a focus on the research-action methodology,the results of the research on some fundamental issues like the relationship with family and the relation with media and social media of the young interviewees,are shown.Finally,in the last part of the article,the interventions carried out by the second-generation young moderators of the social media campaign carried on Facebook and Instagram,are presented in the framework of the online communication campaign born out of the research-action to discuss if and how a prevention process and consequent change with regard to the radicalization factors took place. 展开更多
关键词 PREVENTION radicalization second generation IDENTITY family media social media
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Thiophene-Derived Boron-Containing Dioxoborocyclic Blue-Luminescent Radicals
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作者 Lu Xinyuan Dong Xue +3 位作者 Sun Quanchun Wang Tao Lei Chuanhu Wang Xinping 《有机化学》 北大核心 2026年第2期664-669,共6页
Luminescent radicals have attracted extensive attention due to the unique emission properties from the doublet spin state.However,luminescent radicals are predominantly chloroarylmethyl radicals that emit light in the... Luminescent radicals have attracted extensive attention due to the unique emission properties from the doublet spin state.However,luminescent radicals are predominantly chloroarylmethyl radicals that emit light in the red and near-infrared spectral regions,and the blue emitting radicals remain scarcely reported.Herein,two novel boron-containing dioxoborocyclic blue-luminescent radicals were designed and synthesized by combining dioxoborocyclic radicals with thiophene units.They were characterized by single-crystal X-ray diffraction,UV-Vis spectroscopy,electron paramagnetic resonance(EPR)spectroscopy,and fluorescence spectroscopy in conjunction with theoretical calculations.Theoretical calculations demonstrate that both radicals 3a and 3b emit blue light from the anti-Kasha emission attributed to the effective suppression of IC pathways.Our work offers definitive proof that the boron-containing radical system functions as a highly efficient platform for expanding the diversity of short-wavelength emissive radicals. 展开更多
关键词 borocyclic radical blue-luminescent radicals thiophene-derived
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Photocatalytic Radical-Mediated Synthesis of Unnaturalα-Amino Acids from Heteroaryl Aldehydes
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作者 Ren Ke Zhang Guanglu +3 位作者 Niu Yifan Wang Xiaomeng Chen Canyu Jiang Min 《有机化学》 北大核心 2026年第1期215-224,共10页
Non-naturalα-amino acids(α-AAs)are pivotal in drug and catalysis,yet their synthesis remains challenges.A photocatalytic strategy for the direct construction of N-heteroaryl-containingα-AAs from heteroaryl aldehyde... Non-naturalα-amino acids(α-AAs)are pivotal in drug and catalysis,yet their synthesis remains challenges.A photocatalytic strategy for the direct construction of N-heteroaryl-containingα-AAs from heteroaryl aldehydes via acyl radical intermediates is reported.This method exhibits exceptional functional group tolerance and enables late-stage diversification of peptides and carbonyl-group derivatization.Mechanistic studies confirm a radical-based pathway,while applications in peptide modification highlight its utility in bioorganic chemistry. 展开更多
关键词 PHOTOCATALYTIC non-natural amino acids heteroaryl aldehydes acyl radical electron paramagnetic resonance
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Cul-Catalyzed C—C Bond Coupling Reaction for the Construction of 2-Carbonyl-1,4-diketones
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作者 Liu Yingjie Min Laisheng +3 位作者 Yang Ruirong Song Dongxue Peng Rui Liang Deqiang 《有机化学》 北大核心 2026年第2期603-611,共9页
Transition metal-catalyzed C—C coupling reactions are a core strategy for the construction of carbon-carbon bonds in organic synthesis.Their development has not only promoted the synthesis of drugs,materials,and natu... Transition metal-catalyzed C—C coupling reactions are a core strategy for the construction of carbon-carbon bonds in organic synthesis.Their development has not only promoted the synthesis of drugs,materials,and natural products,but also promoted the development of new synthetic methods,and has also made breakthroughs in mechanism innovation and catalyst design.On this basis,a copper-catalyzed radical reaction between ketones is reported,enabling the synthesis of 2-carbonyl-1,4-diones.The method exhibits excellent applicability to multiple structural types of ketones,including aliphatic ketones with diverse substituents,aromatic ketones,and various simple ketones not limited to acetone,with wide applications,easy implementation,low catalyst toxicity,and low cost,cost-effective,and the product is easy to separate and purify. 展开更多
关键词 transition metal catalysis C—C coupling radical reaction 2-carbonyl-1 4-dione
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Synergistic enhancement of visible-light photocatalytic methyl orange degradation via oxygen vacancy TiO_(2)/Sn_(3)O_(4) composites
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作者 Cailing Jia Zhanting Zhang +4 位作者 Fuwei Yan Fuyue Liu Yanni Wu Fen Wang Haijiao Xie 《日用化学工业(中英文)》 北大核心 2026年第2期191-200,共10页
The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsor... The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsorption and biological degradation,are often hampered by low efficiency and the risk of secondary pollution.Photocatalysis emerges as a promising sustainable alternative;however,the benchmark material titanium dioxide(TiO_(2))suffers from its intrinsic limitations,notably its wide bandgap energy(≥3.4 eV)restricting its activity to the region of the ultraviolet light and its rapid recombination of photogenerated charge carriers.To overcome these constraints,this research focused on synthesizing novel TiO_(2)/Sn_(3)O_(4) heterojunction composite photocatalysts via a solvothermal approach.Comprehensive characterization techniques confirmed the successful formation of the composite,which revealed that ultrathin Sn3O4 nanosheets uniformly coated TiO_(2) nanospheres.This unique architecture effectively reduced the overall crystallinity and introduced the beneficial oxygen vacancies.Under visible-light irradiation(λ≥420 nm),the optimized TiO_(2)/Sn3O4 composite exhibited the exceptional photocatalytic performance,which achieved 96%degradation of MO within just 60 minutes.The calculated apparent kinetic rate constant(0.103 min^(-1))was remarkably(5.15 times)higher than that of pristine TiO_(2).ESR experiments identified that hydroxyl radicals(·OH)was the predominant active species driving the degradation.Furthermore,cyclic degradation tests demonstrated its excellent material stability,with the composite retaining 85%of its initial efficiency after four consecutive reuse cycles.This work underscored the synergistic effects within the TiO_(2)/Sn_(3)O_(4) heterojunction,which significantly enhanced the visible-light absorption,charge separation,and photocatalytic activity,which provided the valuable insights for designing efficient,stable catalysts for the advanced environmental remediation applications. 展开更多
关键词 TiO_(2)/Sn_(3)O_(4)composite visible-light photocatalysis methyl orange degradation oxygen vacancies hydroxyl radicals
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Advances in radical Smiles rearrangement
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作者 Nianhua Luo Jiayi Jiang +5 位作者 Muhammad Suleman Zhaowen Liu Shuping Huang Wei Xiao Jie Wu Jiapian Huang 《Chinese Chemical Letters》 2026年第2期159-176,共18页
The Smiles rearrangement is an exceptionally versatile method in organic synthesis,providing a broad canvas for designing cascade reactions that construct new Csp^(2)-Y(Y=C,O,N,S,CO,etc.)bonds.Among the various types ... The Smiles rearrangement is an exceptionally versatile method in organic synthesis,providing a broad canvas for designing cascade reactions that construct new Csp^(2)-Y(Y=C,O,N,S,CO,etc.)bonds.Among the various types of Smiles rearrangement,the radical-type variant has emerged as a more powerful,mild,efficient,and modern synthetic technique compared to its traditional ionic counterpart.This approach excels in generating new(hetero)aromatic migration products,enabling significant advancements in recent years.This tutorial review focuses on the recent progress,since 2016,in the development and application of radical Smiles rearrangement in organic chemistry.Special attention is paid to novel transformations achieved through photochemical,electrochemical,and transition metal catalysis methods. 展开更多
关键词 Radical Smiles rearrangement Radical chemistry PHOTOCATALYSIS ELECTROCATALYSIS Transition metal-catalyzed
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Initial case series and perioperative outcomes of single-port robotic radical prostatectomy:the Italian experience
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作者 Gianluca Spena Francesco Passaro +10 位作者 Achille Aveta Roberto Contieri Alessandro Izzo Giuseppe Quarto Giovanni Grimaldi Luigi Castaldo Dario Franzese Raffaele Muscariello Savio Domenico Pandolfo Antonio Tufano Sisto Perdonà 《The Canadian Journal of Urology》 2026年第1期117-123,共7页
Background:The Da Vinci Single-Port Robotic System(Da Vinci-SP),introduced by Intuitive(CA,USA)in 2018 in the USA and in 2024 in Europe,integrates advanced features like a flexible camera and articulating instruments.... Background:The Da Vinci Single-Port Robotic System(Da Vinci-SP),introduced by Intuitive(CA,USA)in 2018 in the USA and in 2024 in Europe,integrates advanced features like a flexible camera and articulating instruments.It has garnered significant interest in urology.Our report presents the first described European series of Radical Prostatectomies using the Da Vinci SP at the leading Italian center,Istituto Nazionale Tumori di Napoli,IRCCS“G.Pascale”Foundation,detailing the technical differences and challenges faced by experienced multiport robotic surgeons.Methods:Sixteen patients have been enrolled and underwent Single-Port(SP)Robot-Assisted Radical Prostatectomy(SP-RARP).Baseline characteristics of the patients were collected.We provided a step-by-step description of the surgical technique.Oncological outcomes have been evaluated and compared with magnetic resonance imaging(MRI)and biopsy results.Intraoperative,perioperative,and postoperative complications,surgical outcomes,functional outcomes,and technical issues of the new system were also documented.Results:All surgeries were successfully performed without the need for conversion.An extraperitoneal approach was used for all patients.Median Console time was 110 min.No complications were reported.The estimated median blood loss was 175 cc.Discharge from the hospital was on the first post-operative day for all patients.Bladder catheter removal was on day 7 without the need for cystography.Conclusions:We presented the first European case series of SP-RARP,reporting our experience and confirming the procedure’s feasibility for a highly experienced robotic surgeon.Experience with an extraperitoneal approach using the multiport(MP)platform,combined with well-conducted training for the SP system,may facilitate the transition to SP surgery.Further procedures and studies are needed to evaluate the oncological and functional outcomes. 展开更多
关键词 single-port robotic surgery prostate cancer robot-assisted radical prostatectomy(RARP) radical prostatectomy
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Visible-light induced cascade sulfonation/cyclization reaction in water towards sulfonated dihydroisoquinolino[1,2-b]quinazolinones
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作者 Jun Huang Jiangping Qin +3 位作者 Caijin Ban Jingmei Yuan Jing Yang Guoping Yang 《Chinese Chemical Letters》 2026年第2期415-418,共4页
A visible-light induced cascade sulfonation/cyclization reaction of 3-allyl-2-arylquinazolinones employing water as an environmentally friendly solvent was revealed.This transition metal-free protocol,using 9-mesityl-... A visible-light induced cascade sulfonation/cyclization reaction of 3-allyl-2-arylquinazolinones employing water as an environmentally friendly solvent was revealed.This transition metal-free protocol,using 9-mesityl-10-methylacridinium perchlorate as the photocatalyst,represents a masterly tactic for the synthesis of sulfonated dihydroisoquinolino[1,2-b]quinazolinones featuring mild conditions,facile operation,and broad substrate scope. 展开更多
关键词 Environmentally friendly solvent SULFONATION Radical cascade cyclization VISIBLE-LIGHT QUINAZOLINONE
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Development and Evaluation of Mechanism for Air pollution compleX Version 1.0(MAX1)
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作者 Yanhui LIU Houhua ZHOU +12 位作者 Wenyu WEI Xueshun CHEN Ming ZHOU Yuehui LIU Xuefei MA Xinping YANG Huan SONG Xiaorui CHEN Haichao WANG Zhaofeng TAN Zifa WANG Yuanhang ZHANG Keding LU 《Advances in Atmospheric Sciences》 2026年第4期695-705,I0007-I0027,共32页
The Mechanism for Air pollution compleX version 1.0(MAX1),describing detailed tropospheric chemical processes,has been developed based on the latest knowledge.MAX1 contains 940 reactions,including photolysis,gaseous r... The Mechanism for Air pollution compleX version 1.0(MAX1),describing detailed tropospheric chemical processes,has been developed based on the latest knowledge.MAX1 contains 940 reactions,including photolysis,gaseous reactions,and heterogeneous reactions of 300 species,which is adequate for both box model and climate transport model(CTM)applications.Detailed chemical processes of chlorine chemistry,chemistry of Criegee intermediates,and heterogeneous uptake of HO_(2) and N_(2)O_(5) have been implemented and updated.With this level of explicitness,MAX1 can support investigations into the quantification of secondary pollutant productions and the chemical behavior of the crucial intermediates,such as organic peroxy radicals.Box model and CTM tests were conducted to evaluate the performance of MAX1 from different perspectives.Simulations of MAX1 successfully captured the variation of ozone in all cases tested.Meanwhile,significant improvement was made on predictions of radicals compared to other mechanisms,especially under the low NO_(x) environment,with good similarity to simulations of a nearly explicit chemical mechanism(i.e.,Master Chemical Mechanism)that contains over 17000 reactions.The computational expense of MAX1 is acceptable and it can be applied in atmospheric scientific research and air quality prediction.MAX1 introduces new dimensions in atmospheric chemistry modeling,and its potential application in policymaking is a promising yet exploratory step.It offers improved insights into air quality dynamics,which could assist policymakers in making more informed decisions.However,the translation of its detailed chemical understanding into practical strategies remains an area for further investigation.This model suggests a path towards more nuanced air pollution control methods,contributing to ongoing efforts in environmental management. 展开更多
关键词 chemical mechanism air pollution complex OZONE RADICAL tropospheric chemistry
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Radical-induced selective oxidation and depression of pyrite in copper flotation
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作者 Richard Li Jie Lee Wen-Da Oh +1 位作者 Zhiyong Gao Yongjun Peng 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期507-517,共11页
Selective depression of pyrite remains a major bottleneck in copper flotation,particularly when high-pyrite ores are processed and saline water is used.In such environments,conventional approaches using lime and inert... Selective depression of pyrite remains a major bottleneck in copper flotation,particularly when high-pyrite ores are processed and saline water is used.In such environments,conventional approaches using lime and inert grinding media often fail to discriminate ef-fectively between pyrite and valuable copper minerals due to strong copper activation on pyrite surfaces.This study introduced a novel approach using inorganic radicals generated from peroxymonosulfate(PMS)to selectively oxidize and depress pyrite.Flotation tests with synthetic high-pyrite ore blends showed that PMS significantly reduced pyrite recovery while maintaining or improving chalcopyrite flot-ation.Ethylenediaminetetraacetic acid(EDTA)extraction confirmed selective oxidation of pyrite,and electron paramagnetic resonance(EPR)spectroscopy identified hydroxyl(·OH)and sulfate(SO_(4)^(·-))radicals as the dominant reactive species.Iron ions from grinding me-dia and mineral surfaces were identified as key activators of PMS.A major insight was pyrite’s dual role,acting both as a radical scav-enger and an activator,which made it highly reactive and susceptible to radical-induced oxidation.This process converted surface copper-sulfur species into copper hydroxides,effectively suppressing pyrite flotation.While previous studies have applied EPR to detect radicals in simplified activator/precursor systems,this study provides the first direct mechanistic evidence of radical-driven selectivity in flotation by detecting inorganic radicals in a complex flotation slurry,thereby demonstrating their persistence under industrially relevant conditions and establishing a foundation for more effective and targeted flotation strategies. 展开更多
关键词 selective flotation radical oxidation PEROXYMONOSULFATE pyrite depression chalcopyrite recovery
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Photoreduction of Fe(Ⅲ)mediated by structurally different plant-related organic compounds:An EPR study
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作者 Qingchao Li Fengmin Ma +6 位作者 Pu Wang Yu Fu Jinhui Cao Chunxiao Xu Jialin Chen Lingli Wang Zhaohui Wang 《Chinese Chemical Letters》 2026年第2期662-665,共4页
Plant-related organic compound(PROC) may interact with redox-active metals like iron while they are present in soil or aquatic environment, but their effects on the photoreduction of Fe(Ⅲ) remain largely unexplored. ... Plant-related organic compound(PROC) may interact with redox-active metals like iron while they are present in soil or aquatic environment, but their effects on the photoreduction of Fe(Ⅲ) remain largely unexplored. This study investigates the photochemical behavior of Fe(Ⅲ)-PROC complexes using alkaline lignin(AL), betaine hydrochloride(BH), and phytic acid(PA) as representative proxies for PROC. The reductive agent AL demonstrated the ability to directly reduce Fe(Ⅲ) to Fe(Ⅱ). In contrast, BH, being unable to form strong complexes with Fe(Ⅲ), was able to quench·OH, thereby resulting in a shift of the redox equilibrium towards Fe(Ⅱ). PA exhibited a strong binding affinity for Fe(Ⅲ), effectively inhibiting its photoreduction. Electron paramagnetic resonance(EPR) analysis, utilizing 5,5-dimethyl-1-pyrroline-N-oxide(DMPO) as a spin trap, revealed that the DMPO-OH signal detected in photolyzed Fe(Ⅲ)-PROC solutions originated from various pathways. Specifically, uncomplexed Fe(Ⅲ) in AL or BH solutions was shown to oxidize DMPO directly, leading to the formation of a false DMPO-OH adduct. The addition of ethanol to the photolyzed Fe(Ⅲ)-AL and Fe(Ⅲ)-BH systems resulted in the generation of the DMPO-CH(CH_(3))OH adduct, thereby confirming the presence of authentic·OH in these systems. The photolysis of the Fe(Ⅲ)-PA complex may proceed via a photodissociation mechanism, where the resulting loosely bound Fe(Ⅲ)can oxidize DMPO, followed by a nucleophilic attack from water. This research highlights the multifaceted roles of PROC in facilitating the redox cycling of iron within soil and aquatic ecosystems. 展开更多
关键词 Alkaline lignin Hydrochloric betaine Phytic acid Free radical PHOTOCHEMISTRY
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La replaced Bi^(3+)in BiO_(2-x)for oxygen vacancies generation:degradation of antibiotics and biological toxicity elimination
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作者 Jiangtao Niu Jin Zhang +7 位作者 Xiaoxuan Song Naif Abdullah Al-Dhabi Wanhong He Guihua Huang Dujie Feng Wanngwang Tang Mingming Dang Yi Zhou 《Journal of Environmental Sciences》 2026年第2期93-104,共12页
La-BiO_(2-x)composite photocatalyst was successfully synthesized through a single-step hydrothermal strategy.The introduction of La3+into the BiO_(2-x)lattice replaces the Bi^(3+)in the BiO_(2-x)lattice,resulting in a... La-BiO_(2-x)composite photocatalyst was successfully synthesized through a single-step hydrothermal strategy.The introduction of La3+into the BiO_(2-x)lattice replaces the Bi^(3+)in the BiO_(2-x)lattice,resulting in a new defect level and oxygen vacancies(Vo)generation.The·O_(2)^(−)generated in the surface of Vo,which was converted into singlet oxygen(1O2)with the transformation of Bi^(5+)to Bi^(3+).Upon visible(near-infrared)light irradiation,the removal rates of tetracycline(TC),oxytetracycline(OTC),and levofloxacin(LEV)by trace 5%La-BiO_(2-x)(0.1 g/L)reached 84.18%(55.56%),78.85%and 70.12%,respectively.The Toxicity Estimation Software Tool(T.E.S.T)based on Quantitative Structure-Activity Relationship(QSAR)models illustrated that the biological toxicity of TC intermediates can be eliminated by 5%La-BiO_(2-x).The green bean germination rates in 5%La-BiO_(2-x)treated TC solution was close to that in the tap water(100.0%).The inorganic anion and humic acid(HA)exhibited almost no influence on the degradation of TC in lake water and river water.This study enhances the comprehension of biological toxicity elimination in antibiotics degradation process,providing the possibilities for actual applications of La-BiO_(2-x). 展开更多
关键词 PHOTOCATALYSIS LANTHANUM BiO_(2-x) Oxygen vacancy Superoxide radicals
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Asymmetric triple-atomic sites with modulated electronic structure toward boosted peroxymonosulfate activation
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作者 Jinxin Li Yifan Ren +4 位作者 Jianan Gao Nadeeshani Nanayakkara Xin Wang Meng Liu Yanbiao Liu 《Chinese Chemical Letters》 2026年第2期698-703,共6页
Peroxymonosulfate(PMS)-based advanced oxidation technology has been proven to be a viable option for the decontamination of organic pollutants from water bodies.Advanced catalyst design is essential to this technology... Peroxymonosulfate(PMS)-based advanced oxidation technology has been proven to be a viable option for the decontamination of organic pollutants from water bodies.Advanced catalyst design is essential to this technology.Herein,a vanadium-doped LaFeO_(3) perovskite(LFO-V)featuring asymmetric Fe-O-V sites was rationally designed.Thanks to orbital electron interaction between Fe and V atoms,the modified electronic structure elevated electron density near the Fermi energy level while reducing the energy barrier toward effective PMS activation.This facilitated concurrent PMS reduction at the Fe sites to generate SO_(4)^(·-)and·OH(57.7%),and PMS oxidation at V sites to produce ^(1)O_(2)(42.3%).The LFO-V/PMS system demonstrated excellent tetracycline(TC)degradation performance with a 2-fold enhancement in rate constant compared to that of pristine LFO.Further,the LFO-V maintained long-term stability,and the toxicity of degradation intermediates was evaluated through microbial metabolomics.This work establishes an effective route to regulate the PMS activation pathways through precise electronic structure modulation,advancing the rational design of advanced Fenton-like catalysts. 展开更多
关键词 Electric structure modulation Fe-O-V sites Reduction-oxidation Radical species Non-radical species
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Visible light photocatalytic enhanced heterogeneous cobalt catalyzed peroxymonosulfate synergistic process to degradation atrazine:Efficiency,influencing factors,by-products removal and mechanism
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作者 Qingkong Chen Jieyu Xia +3 位作者 Fengjun Liu Jianping Fan Peng Yan Mika Sillanpää 《Journal of Environmental Sciences》 2026年第1期166-177,共12页
This study developed a novel heterogeneous Vis-Photo+Fenton-like system by integrating visible-light-responsive Co_(3)O_(4)/TiO_(2) photocatalysis with peroxymonosulfate(PMS)activation for efficient atrazine(ATZ)degra... This study developed a novel heterogeneous Vis-Photo+Fenton-like system by integrating visible-light-responsive Co_(3)O_(4)/TiO_(2) photocatalysis with peroxymonosulfate(PMS)activation for efficient atrazine(ATZ)degradation.The synergistic process achieved complete ATZ removal within 60 min under near-neutral pH(6.9),outperform-ing individual Fenton-like(39%)and photocatalytic(24%)processes.Key factors influencing the degradation efficiency included light sources(UV>visible),pH(optimal at 6.9),catalyst dosage(0.01 g Co_(3)O_(4)/TiO_(2)),and PMS:ATZ molar ratio(1:2).The system exhibited a synergistic coefficient of 5.03(degradation)and 1.97(miner-alization),attributed to enhanced radical generation and accelerated Co^(3+)/Co^(2+)redox cycling through photoin-duced electron transfer.Intermediate analysis revealed dealkylation,dechlorination,and oxidation pathways,with reduced toxicity of by-products(e.g.,CEAT,CIAT)confirmed by ecotoxicity assessments.The mineralization efficiency(Vis-Photo+Fenton-like)reached 83.1%,significantly higher than that of standalone processes(Fenton-like:43.2%;photocatalysis:30.5%).The catalyst demonstrated excellent stability(nearly 90%recov-ery,<1μg/L Co leaching)and practical applicability.This study provides an efficient,sludge-free,and solar-compatible strategy for eliminating persistent herbicides in water treatment. 展开更多
关键词 Synergistic effect Sulfate radical FENTON-LIKE PHOTOCATALYSIS Visible light Atrazine(ATZ)
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Magnetic field mediated oxygen radical mechanism for enhanced water oxidation
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作者 Xiaoning Li Chongyan Hao +10 位作者 Songzhu Luo Anke Yu Peng Li Bing Xiong Zhengping Fu Justin Zhu Yeow Seow Yalin Lu Xiaolin Wang Tianyi Ma Zhichuan J.Xu Zhenxiang Cheng 《Journal of Energy Chemistry》 2026年第3期116-125,共10页
The spin-sensitive nature of redox reactions in energy conversion systems,such as the oxygen evolution reaction(OER),has attracted increasing attention due to its potential for enhancing catalytic efficiency.Magnetic ... The spin-sensitive nature of redox reactions in energy conversion systems,such as the oxygen evolution reaction(OER),has attracted increasing attention due to its potential for enhancing catalytic efficiency.Magnetic fields(MFs)have been proposed to enhance OER performance by influencing the spin states of oxygen intermediates.However,prior study has predominantly focused on MF effects mediated by the intrinsic magnetic properties of electrocatalysts or magnetohydrodynamics.In this work,we report a universal enhancement in OER activity,achieving over 150% increase in current density under a200 mT MF across diamagnetic,paramagnetic and magnetic electrocatalysts in 1 M KOH.Through systematic investigation of MF orientation and strength,pH,applied potentials,and the use of benzoquinone radical scavenger,we demonstrate that MF-driven performance improvements arise from direct modulation of oxygen radical spin states.Specifically,MFs promote the formation of spin-triplet oxygen intermediates(↑O–O↑),a critical step for O–O bond formation,independent of the catalyst's intrinsic magnetism.However,the local magnetic environment near the catalyst surface,governed by its magnetic properties,indirectly influences radical spin dynamics by alternating the effective field experienced by intermediates.These findings redefine the role of spin manipulation in electrocatalysis,advancing understanding of MF-driven spin effects in redox reactions. 展开更多
关键词 Oxygen evolution reaction Magnetic field Radical pair mechanism SPIN MAGNETISM
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Ultrasound-induced Activation of Tetravalent Platinum Polyglutamate Nanoprodrug Accelerated by Coumarin Derivatives
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作者 Chao-Ying Kong Chu-Wen Luo +2 位作者 Ya-Jun Xu Na Shen Zhao-Hui Tang 《Chinese Journal of Polymer Science》 2026年第1期44-56,I0009,共14页
Given that platinum-based drugs are widely used clinically as chemotherapeutic agents,their severe toxic side effects have attracted significant attention.Consequently,the development of novel nanoprodrugs based on lo... Given that platinum-based drugs are widely used clinically as chemotherapeutic agents,their severe toxic side effects have attracted significant attention.Consequently,the development of novel nanoprodrugs based on low-toxicity tetravalent platinum(Pt(Ⅳ))com plexes holds substantial research value.Herein,we discovered that coumarin derivatives exhibit inherent antitumor efficacy and significantly enhance superoxide anion radicals(·O_(2)^(-))generation in aqueous solutions under ultrasound(US)irradiation.Given that·O_(2)^(-)is known to mediate the reduction of Pt(Ⅳ)to divalent platinum(Pt(Ⅱ)),we engineered an US-responsive dual-drug nanoprodrug(P-cisPt(Ⅳ)@5-MOP).This nanoprodrug was prepared by covalently conjugating Pt(Ⅳ)and methoxy polyethylene glycol hydroxyl(m PEG-OH)to a poly(_(L)-glutamic acid)(PLG)carrier,followed by encapsulating coumarin derivatives.Under low-intensity US irradiation(1.5 W/cm^(2),1 MHz,10 min),P-cisPt(Ⅳ)@5-MOP achieved a Pt(Ⅳ)reduction rate of 91.4%.Furthermore,upon US exposure,its half-maximal inhibitory concentration(IC_(50))against 4T1 breast cancer cells decreased dramatically from 25.7μmol/L to 0.1μmol/L.Remarkably,this system combined with US therapy yielded a tumor inhibition rate of 90.9%,with 40%of tumor-bea ring mice achieving com plete eradication of tumors,while exhibiting low systemic toxicity.Collectively,this work not only identifies a novel sonosensitizer capable of generating·O_(2)^(-)but also develops a new class of ultrasound-activatable Pt(Ⅳ)nanoprodrug. 展开更多
关键词 Ultrasound activation Ultrasound chemistry Platinum drug COUMARIN Superoxide anion radical
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Study on the mechanism of temperature-responsive composite inhibitors in suppressing coal spontaneous combustion at different reaction stages
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作者 Yumo Wu Dan Zhao Jinzhang Jia 《International Journal of Mining Science and Technology》 2026年第3期635-649,共15页
Temperature is one of the main causes of spontaneous coal combustion.To improve the flame retardant performance,CaCl2,ammonium polyphosphate(APP),and calcium phosphate(CaHP)were compounded to control the temperature r... Temperature is one of the main causes of spontaneous coal combustion.To improve the flame retardant performance,CaCl2,ammonium polyphosphate(APP),and calcium phosphate(CaHP)were compounded to control the temperature response of different stages of coal spontaneous combustion through physical and chemical synergy.Simultaneous thermal analysis,thermogravimetric-Fourier infrared spectroscopy(TG-FTIR),in-situ FTIR and electron paramagnetic resonance(EPR)were used to study the multitemperature stage synergistic inhibition of coal spontaneous combustion.The results show that the proposed method is effective.By obtaining the characteristics of the spontaneous combustion reaction stage of coal in advance,the method of configuring an appropriate composite inhibitor can effectively realize the intelligent control of the temperature response of coal spontaneous combustion.The ignition point of long-flame coal increased by 37.15℃.The inhibition rate of the gas phase products was more than 20%,and the inhibition rate of the functional groups was more than 30%.It has a good quenching effect on free radicals and can effectively inhibit the oxidation activity of active free radicals such as H,HO,and O.The results provide experimental and theoretical support for the study of temperature-responsive composite flame retardants for coal with different metamorphic degrees. 展开更多
关键词 Coal spontaneous combustion Composite flame retardants Gas-phase product Free radical Temperature-response
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The Warburg Effect Beyond Cancer:Melatonin as a Metabolic Modulator in Non-Neoplastic Disorders
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作者 José A.Boga Ana Coto-Montes Russel J.Reiter 《BIOCELL》 2026年第1期28-45,共18页
Aerobic glycolysis,also known as the Warburg effect,and the accumulation of lactate that it causes,are increasingly recognized outside the field of oncology as triggers of chronic non-neoplastic disorders.This review ... Aerobic glycolysis,also known as the Warburg effect,and the accumulation of lactate that it causes,are increasingly recognized outside the field of oncology as triggers of chronic non-neoplastic disorders.This review integrates preclinical and clinical evidence to evaluate the ability of melatonin to reverseWarburg-effect-like metabolic reprogramming.Literature on neurodegeneration,age-related sarcopenia,type 2 diabetes,chronic kidney disease,heart failure and pulmonary arterial hypertension(PAH)has been reviewed and synthesised.In all of these conditions,hypoxia-inducible factor 1α(HIF-1α)and pyruvate dehydrogenase kinase 4(PDK4)inhibit the pyruvate dehydrogenase complex.This diverts pyruvate away fromthe tricarboxylic acid(TCA)cycle and promotes glycolysis.In cell and animal models,melatonin consistently inhibits PDK4,destabilizes HIF-1αunder normoxic conditions,activates SIRT1/3-dependentmitochondrial biogenesis andmitophagy,and eliminates reactive oxygen and nitrogen species.These actions reduce lactate production,restore oxidative phosphorylation and attenuate tissue damage.This appears to induce cognitive and synaptic improvements in Alzheimer’s and Parkinson’s disease models,increased muscle mass and function in ageing rodents,improved insulin sensitivity alongside suppression of hepatic gluconeogenesis in diabetic models,reduced fibrosis in nephropathy,and normalization of vascular remodeling in hypoxia-induced pulmonary arterial hypertension(PAH).Early-stage clinical trials corroborate a decrease in oxidative and inflammatorymarkers,improved sleep quality and modest cognitive benefits.However,they report conflicting effects on insulin sensitivity,which are largely related to the dose and timing of administration in relation to food intake.Overall,the current data suggest that melatonin is a pleiotropic metabolic modulator capable of counteracting the Warburg phenotype in multiple organs.However,human studies remain scarce,and well-designed randomised trials incorporating chronotherapy are needed before clinical adoption. 展开更多
关键词 Neurodegenerative diseases ageing-related conditions metabolic disorders pyruvate dehydrogenase free radicals glucose processing
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