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Redefining selectivity paradigms in electrochemical nitrogen reduction reaction on confined dual-atom catalysts
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作者 Nana Hu Xingshuai Lv +2 位作者 Guobo Chen Thomas Frauenheim Liangzhi Kou 《Science China Materials》 2026年第3期1719-1728,共10页
The premature decay of electrochemical nitrogen reduction reaction(eNRR)performance at low electrode potentials remains a major obstacle to practical applications,which is primarily attributed to the competition from ... The premature decay of electrochemical nitrogen reduction reaction(eNRR)performance at low electrode potentials remains a major obstacle to practical applications,which is primarily attributed to the competition from the hydrogen evolution reaction(HER).A new paradigm capable of transcending current selectivity constraints is urgently required to advance eNRR toward industrial implementation.In this work,we propose two practical selectivity descriptors(ΔΔG andΔU)based on a systematic investigation of the potential-dependent competition between eNRR and HER on confined dual-atom catalysts.The descriptorΔΔG(G_(N_(2))-ΔG_(H))identifies the potential range where N_(2)adsorption dominates over H adsorption,whileΔU(U_(cross)-U_(eNRR))specifies the potential range to trigger direct eNRR,offering a quantitative benchmark for rational catalyst design.Ideal catalysts should maintain N_(2)-preferential adsorption across a broad potential window to facilitate direct eNRR.Guided by this insight,we demonstrate that confined dual-atom configurations with optimized interatomic distances can simultaneously achieve both overwhelming N_(2)adsorption and sufficient activation,thereby overcoming the conventional selectivity limitations.This strategy enables ammonia synthesis with industrially relevant production rates and current density even at elevated potentials.Our mechanistic insights not only elucidate the root causes of performance limitations in eNRR but also offer a rational design framework for developing high-performance catalysts across a broad range of electrochemical transformations. 展开更多
关键词 electrochemical nitrogen reduction selectivity confined dual-atom catalysts diporphyrins constant-potential/solvation model
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Enhanced selectivity of catalytic hydrogenation of halogenated nitroaromatics by interfacial effects
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作者 HUANG Rui LIU Shengjie +1 位作者 WU Qingyuan ZHENG Nanfeng 《无机化学学报》 北大核心 2025年第1期201-212,共12页
The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts c... The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts contained Pd species in mixed valence states,with high valence Pd at the metal‑support interface and zero valence Pd at the metal surface.While the strong coordination of triphenylphosphine(PPh3)to Pd0 on the Pd surface prevents the adsorption of halogenated nitroaromatics and thus dehalogenation,the coordination of sodium metavanadate(NaVO3)to high‑valence Pd sites at the interface helps to activate H2 in a heterolytic pathway for the selective hydrogenation of nitro‑groups.The excellent catalytic performance of the interfacial active sites enables the selective hydrogenation of a wide range of halogenated nitroaromatics. 展开更多
关键词 halogenated nitroaromatic heterogeneous catalysis HYDROGENATION selectivity control interfacial effect
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Confined electric field in nano-sized channels of ionic porous framework towards unique adsorption selectivity
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作者 Congyan Liu Xueyao Zhou +2 位作者 Fei Ye Bin Jiang Bo Liu 《Chinese Chemical Letters》 2025年第2期437-441,共5页
Efficient selective adsorption and separation using porous frameworks are critical in many industrial processes,where adsorption energy and dynamic diffusion rate are predominant factors governing selectivity.They are... Efficient selective adsorption and separation using porous frameworks are critical in many industrial processes,where adsorption energy and dynamic diffusion rate are predominant factors governing selectivity.They are highly susceptible to framework charge,which plays a significant role in selective adsorption.Currently,ionic porous frameworks can be divided into two types.One of them is composed of a charged backbone and counter ions.The framework with zwitterionic channels is another type.It is composed of regular and alternating arrangements of cationic and anionic building units.Herein,we report a hydrogen-bonded ionic framework(HIF)of{(CN_(3)H_(6))_(2)[Ti(μ_(2)-O)(SO_(4))_(2)]}_nwith 1D channel exhibits unique adsorption selectivity for Ar against N_(2)and CO_(2).Density functional theory(DFT)results suggest that CO_(2)cannot be adsorbed by HIF at the experimental temperature due to a positive adsorption free energy.In addition,due to a relatively large diffusion barrier at 77 K,N_(2)molecules hardly diffuse in HIF channels,while Ar has a negligible diffusion barrier.The unique net positively-charged space in the channel is the key to the unusual phenomena,based on DFT simulations and structural analysis.The findings in this work proposes the new adsorption mechanism and provides unique perspective for special separation applications,such as isotope and noble gasses separations. 展开更多
关键词 Adsorption selectivity Channel Positive electric field GUANIDINIUM
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Improved N_(2)selectivity for low-temperature NO_(x)reduction over etched ZSM-5 supported MnCe oxide catalysts
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作者 Shanyuan Bi Jin Zhang +4 位作者 Dengchao Peng Danhong Cheng Jianping Zhang Lupeng Han Dengsong Zhang 《Chinese Chemical Letters》 2025年第5期639-644,共6页
Developing a high-efficiency catalyst with both superior low-temperature activity and good N_(2)selectivity is still challenging for the NH_(3)selective catalytic reduction(SCR)of NO_(x)from mobile sources.Herein,we d... Developing a high-efficiency catalyst with both superior low-temperature activity and good N_(2)selectivity is still challenging for the NH_(3)selective catalytic reduction(SCR)of NO_(x)from mobile sources.Herein,we demonstrate the improved low-temperature activity and N_(2)selectivity by regulating the redox and acidic properties of MnCe oxides supported on etched ZSM-5 supports.The etched ZSM-5 enables the highly dispersed state of MnCeOx species and strong interaction between Mn and Ce species,which promotes the reduction of CeO2,facilitates electron transfer from Mn to Ce,and generates more Mn^(4+)and Ce^(3+)species.The strong redox capacity contributes to forming the reactive nitrate species and-NH_(2)species from oxidative dehydrogenation of NH_(3).Moreover,the adsorbed NH_(3)and-NH_(2)species are the reactive intermediates that promote the formation of N_(2).This work demonstrates an effective strategy to enhance the low-temperature activity and N_(2)selectivity of SCR catalysts,contributing to the NO_(x)control for the low-temperature exhaust gas during the cold-start of diesel vehicles. 展开更多
关键词 NO_(x) Selective catalytic reduction Mn-based catalyst Low-temperature activity N_(2)selectivity
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Food selectivity and autism:A systematic review
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作者 Rosaria Ferrara Leonardo Iovino +3 位作者 Lidia Ricci Angiola Avallone Roberto Latina Pasquale Ricci 《World Journal of Clinical Pediatrics》 2025年第3期272-280,共9页
BACKGROUND Autism spectrum disorder(ASD)is a neurodevelopmental disorder that manifests in the first years of life,with a complex pathogenesis influenced by biological,genetic and epigenetic factors.Many children with... BACKGROUND Autism spectrum disorder(ASD)is a neurodevelopmental disorder that manifests in the first years of life,with a complex pathogenesis influenced by biological,genetic and epigenetic factors.Many children with ASD display marked food selectivity,often restricting themselves to a narrow range of foods.The problems associated with feeding children with ASD can vary widely,from mild cases that pose no immediate health risks,to more severe situations with a risk of mal-nutrition or,conversely,overeating.This scoping review aims to provide an in-depth overview of the frequency,nature and factors related to food selectivity in children with autism.AIM To comprehensively review the literature on food selectivity in ASD.METHODS A systematic review of the literature was conducted using the PubMed,Web of Science and EBSCO databases,to identify articles published in English from 2014 until 2024.Studies on a sample diagnosed with ASD and food selectivity were included.The selected databases were chosen for their broad coverage of the scientific literature.These databases represent reliable sources of high-quality articles,ensuring a comprehensive and up-to-date search.RESULTS We evaluated 222 studies on food selectivity in autism,from which duplicates were removed and unrelated titles were filtered out.Finally,9 articles were included in the review.Five articles provide a general overview of the phenomenon,analysing its nature and factors.Two studies delve into sensory sensitivity,in particular the impact of food textures,tastes and smells.Finally,two studies focus on problem behaviour during mealtimes.CONCLUSION Children with ASD have greater food selectivity than the neurotypical population.The diet should contain a greater variety of fruit,vegetables,yoghurt,while reducing the consumption of rice and pasta. 展开更多
关键词 Food selectivity AUTISM DEVELOPMENT Autism spectrum disorder CHILDREN
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Breaking the selectivity barrier in glycerol electrooxidation to glyceraldehyde via redox mediation
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作者 Zhenghao Mao Wenjing Xu +1 位作者 Na Han Yanguang Li 《Chinese Journal of Catalysis》 2025年第11期336-342,共7页
Aldehydes are valuable intermediates with widespread industrial applications,and their traditional synthesis relies on chemical oxidation that is often hazardous and environmentally unfriendly.Electrochemical oxidatio... Aldehydes are valuable intermediates with widespread industrial applications,and their traditional synthesis relies on chemical oxidation that is often hazardous and environmentally unfriendly.Electrochemical oxidation offers a more sustainable and milder alternative;however,it faces challenges such as aldehyde overoxidation and susceptibility to base-catalyzed Cannizzaro disproportionation.Electrochemical glycerol oxidation to glyceraldehyde is a representative example,which typically requires precious metal-based electrocatalysts but still suffers from low selectivity and activity.Here,we report a metal-free oxidation strategy mediated by 2,2,6,6-tetramethylpiperidine-1-oxyl.By systematically investigating the redox thermodynamics and kinetics of TEMPO across a broad pH range,we construct a Pourbaix diagram and elucidate the relative kinetics of each reaction step.These insights allow us to explain the anomalously high apparent Faradaic efficiency(~200%)observed under acidic conditions,and identify neutral media as the optimal environment for selective glyceraldehyde production.Under optimized conditions,our system achieves a glyceraldehyde Faradaic efficiency exceeding 93%and a partial current density of 23.3 mA cm^(-2)at 0.57 V—more than doubling the performance of the best reported precious metal-based systems.Furthermore,the versatility of this strategy extends to the selective oxidation of other primary alcohols to their corresponding aldehydes with near-unity selectivity. 展开更多
关键词 Electrochemical glycerol oxidation GLYCERALDEHYDE Redox mediator selectivity Pourbaix diagram
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Indium-captured zirconium-porphyrin frameworks displaying rare multi-selectivity for catalytic transfer hydrogenation of aldehydes and ketones
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作者 Hua Liu Jian Zhao +5 位作者 Qi Li Xiang-Yu Zhang Zhi-Wei Zheng Kun Huang Da-Bin Qin Bin Zhao 《Chinese Chemical Letters》 2025年第6期648-656,共9页
Selective catalytic transfer hydrogenation(CTH)of carbonyl compounds to obtain specific alcohols holds significant importance across various fields.Achieving multiple selectivity in CTH is particularly crucial,but ful... Selective catalytic transfer hydrogenation(CTH)of carbonyl compounds to obtain specific alcohols holds significant importance across various fields.Achieving multiple selectivity in CTH is particularly crucial,but full of great challenge.Herein,a cationic In-captured Zr-porphyrin framework(1)with nanosized pores/cages was successfully constructed and showed high structure stability.Catalytic investigations revealed that 1 displayed highly multi-selective CTH of aldehydes and ketones containing both chemo-and size selectivity for the first time.The CTH of aldehydes and ketones exhibited remarkable reductive selectivity of 99%towards C=O bonds into CH–OH in the presence of-NO_(2),-CN and C=C groups.Through tuning the reaction conditions,1 also exhibited highly selective reduction of 97%for-CHO groups in the simultaneous presence of-CHO and-COCH3groups in intra-and intermolecular settings.Remarkably,reductive selectivity towards-CHO group remained prominent among five concurrent unsaturated groups mentioned above.Additionally,the definite pore size of 1 facilitated volume control of substrates,enabling size selectivity.1 as a heterogeneous catalyst was further confirmed by leaching tests,and maintained high activity even after being used for at least six cycles.Mechanistic studies have revealed that Zr6O8clusters served as the catalytic centers and the observed chemoselectivity mainly results from the synergistic effect of distinct metal sites within 1.The heightened selectivity towards-CHO over-COCH_(3)can be attributed to the easier realization of transfer hydrogenation processes for-CHO compared to-COCH_(3). 展开更多
关键词 Metal-organic framework Heterogeneous catalysis Transfer hydrogenation Multiple selectivity Synergistic effect
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Biosorption selectivity of rare earth elements onto Euglena mutabilis suspensions and biofilms and the effect of divalent metal ions
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作者 Mitchell T.E.Zak Vladimiros G.Papangelakis D.Grant Allen 《Journal of Rare Earths》 2025年第10期2269-2275,I0007,共8页
The increasing demand for electronics has led to a desire to recover rare earth elements(REEs) from nonconventional sources,including mining and liquid waste effluents.Biosorption could be a promising method for adsor... The increasing demand for electronics has led to a desire to recover rare earth elements(REEs) from nonconventional sources,including mining and liquid waste effluents.Biosorption could be a promising method for adsorbing REEs onto microalgae,but biomass immobilization and light delivery challenges remain.It was recently shown that REEs biosorb 160% more on algal biofilms than suspended biomass due to the extracellular polymeric substance(EPS) matrix that grows abundantly in biofilms.In this work,we present findings on biosorption selectivity for different REEs in sulfate solutions.The maximum adsorption capacities of Euglena mutabilis suspensions and biofilms were determined for a mixed REE sulfate solution at an equimolar initial concentration range of 0.1-1 mol/L of each REE ion.The highest adsorption capacities for the suspension are for Sm and Eu which are 57% and 46% higher,respectively,compared to the average REE adsorption capacity.The biofilms also preferentially adsorb Sm,Eu,Yb and Lu at 0.035,0.033,0.033,and 0.031 mmol/g,respectively.The impact of dissolved divalent ions of Ca,Mg,and Fe on REE adsorption was also assessed.When Ca and Mg are added in equimolar amounts to0.1-1 mmol/L solutions of equimolar La,Eu,and Yb sulfate,the amount of REEs adsorbed onto suspensions increases by 30% while when Fe is added,it decreases by 10%.No change is observed in biofilms except when Fe is added resulting in a reduction of the adsorption capacity by 40%.A possible explanation for the role of Fe is attributed to the formation of stronger bonds at the binding sites compared to Ca and Mg. 展开更多
关键词 Algal biofilm BIOSORPTION Extracellular polymeric substances Rare earth element selectivity
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Surface oxygen vacancies of BiOBr regulating piezoelectricity for enhancing efficiency and selectivity of photocatalytic CO_(2) reduction
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作者 Cunjun Li Jie He +4 位作者 Tianle Cai Xianlei Chen Hengcong Tao Yingtang Zhou Mingshan Zhu 《Chinese Journal of Catalysis》 2025年第7期130-143,共14页
Although defect engineering has been widely used to boost catalytic CO_(2) photoreduction,the piezoelectric polarized properties induced by structure changes through introducing defects are always ignored.Here we repo... Although defect engineering has been widely used to boost catalytic CO_(2) photoreduction,the piezoelectric polarized properties induced by structure changes through introducing defects are always ignored.Here we report a new kind of bismuth oxybromide(BiOBr,BOB)with piezoelectric property regulated by oxygen vacancies(OVs).Compared with pure BOB,BOB with OVs(BOB-OV)could enhance photocatalytic CO_(2) reduction efficiency under the ultrasonic force,achieving durable CO_(2) reduction process to superior production rates of CO(54.4μmol g^(-1) h^(-1))with a high selectivity(92%).Moderate OVs concentration changed the degree of Bi-Br stretching in the BOB-OV to produce strong dipole moments,which endowed BOB-OV with strong spontaneous piezoelectric polarization ability under external force.Ultrasonic piezoelectric effects were innovatively integrated into the photocatalytic reaction,which not only provided an alternating force field to modulate the spontaneous polarization of BOB-OV,thereby maintaining efficient photogenerated charge separation,but also lowered the reaction energy barrier of CO_(2) by high stress,ultimately improving CO product selectivity.This study is the first to leverage OVs-induced piezoelectric polarization effects to enhance the performance and product selectivity of photocatalytic CO_(2) reduction,providing new directions and insights for defect engineering to contribute to photocatalysis. 展开更多
关键词 BiOBr Oxygen vacancy PIEZOELECTRICITY High selectivity Photocatlytic CO_(2)reduction
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2D copper-iron bimetallic metal-organic frameworks for reduction of nitrate with boosted efficiency and ammonia selectivity
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作者 Qian Ma Yinghao Xue +4 位作者 Chuning Zhang Yanyan Chen Wei Teng Hua Zhang Jianwei Fan 《Journal of Environmental Sciences》 2025年第3期374-385,共12页
Electrocatalytic reduction of nitrate to ammonia has been considered a promising and sustainable pathway for pollutant treatment and ammonia has significant potential as a clean energy.Therefore,the method has receive... Electrocatalytic reduction of nitrate to ammonia has been considered a promising and sustainable pathway for pollutant treatment and ammonia has significant potential as a clean energy.Therefore,the method has received much attention.In this work,Cu/Fe 2D bimetallic metal-organic frameworks were synthesized by a facile method applied as cathode materials without high-temperature carbonization.Bimetallic centers(Cu,Fe)with enhanced intrinsic activity demonstrated higher removal efficiency.Meanwhile,the 2D nanosheet reduced themass transfer barrier between the catalyst and nitrate and increased the reaction kinetics.Therefore,the catalysts with a 2D structure showed much better removal efficiency than other structures(3D MOFs and BulkMOFs).Under optimal conditions,Cu/Fe-2D MOF exhibited high nitrate removal efficiency(87.8%)and ammonium selectivity(89.3%)simultaneously.The ammonium yielded up to significantly 907.2μg/(hr·mg_(cat))(7793.8μg/(hr·mg_(metal)))with Faradaic efficiency of 62.8%at an initial 100 mg N/L.The catalyst was proved to have good stability and was recycled 15 times with excellent effect.DFT simulations confirm the reduced Gibbs free energy of Cu/Fe-2D MOF.This study demonstrates the promising application of Cu/Fe-2D MOF in nitrate reduction to ammonia and provides new insights for the design of efficient electrode materials. 展开更多
关键词 Metal-organic frameworks Electrochemical denitrification Ammonium selectivity 2D bimetal materials
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A stable scandium(III) metal-organic framework with introduced nitrate ions for enhancing C_(2)H_(6)/C_(2)H_(4) selectivity in the separation of MTO products
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作者 Yajun Gao Xinyu Yang +1 位作者 Jian Su Zhizhong Li 《Chinese Journal of Structural Chemistry》 2025年第6期18-25,共8页
Based upon the thiophene-2,5-dicarboxylic acid(H_(2)Tdc),a novel[Sc_(3)(μ_(2)-OH)_(3)(CO_(2))_(4)O_(6)]n inorganic chain-based Sc-MOF with decorated nitrate ions,{[Sc_(3)(OH)_(2)(Tdc)_(3)(NO_(3))]⋅H_(2)O}_(∞)(AEU-1;... Based upon the thiophene-2,5-dicarboxylic acid(H_(2)Tdc),a novel[Sc_(3)(μ_(2)-OH)_(3)(CO_(2))_(4)O_(6)]n inorganic chain-based Sc-MOF with decorated nitrate ions,{[Sc_(3)(OH)_(2)(Tdc)_(3)(NO_(3))]⋅H_(2)O}_(∞)(AEU-1;AEU for Army Engineering University of PLA),was synthesized,which shows good water and chemical stabilities.Significantly,due to channel constriction accompanied by the polar window caused by introducing nitrate ions,AEU-1 exhibits high C_(2)H_(6)/C_(2)H_(4)adsorption selectivity comparable to many famous C_(2)H_(6)-selective MOFs,making it a promising candidate for the purification of methanol-to-olefin(MTO)products.Furthermore,theoretical investigations reveal that the introduced nitrate ions in AEU-1 as the main adsorption sites could provide strong interactions between the framework and C2H6/C3H6 in the full-contacting mode,leading to an increase in the adsorption enthalpies(Qst)of C_(2)H_(6)and C_(3)H_(6),and thus further improving the C_(2)H_(6)/C_(2)H_(4)and C_(3)H_(6)/C_(2)H_(4)adsorption selectivity.Our work could open up a new avenue for constructing MOFs with inorganic polar moieties as adsorption sites for one-step C_(2)H_(4)purification and C3H6 recovery from MTO mixtures with high selectivity. 展开更多
关键词 Scandium(III)metal-organic framework Nitrate ions selectivity MTO product separation
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Vibrational Mode Selectivity in Dissociative Ionization of 2-Ethoxyethanol:An IR-VUV NRIFD-IR Spectroscopic Study
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作者 Licheng Zhong Ende Huang +3 位作者 Guosheng Wang Jingning Xue Wenrui Dong Xueming Yang 《Chinese Journal of Chemical Physics》 2025年第2期156-163,I0002-I0006,I0039,共14页
In the current work,we studied the infrared spectroscopy of neutral and cationic 2-ethoxyethanol(CH_(3)CH_(2)O CH_(2)CH_(2)OH,2-EE)using the infrared(IR)-vacuum-ultraviolet(VUV)non-resonant ionization and fragmenta-ti... In the current work,we studied the infrared spectroscopy of neutral and cationic 2-ethoxyethanol(CH_(3)CH_(2)O CH_(2)CH_(2)OH,2-EE)using the infrared(IR)-vacuum-ultraviolet(VUV)non-resonant ionization and fragmenta-tion detected IR spectroscopy(NRIFD-IR)technique.The spectral range was from 2700 cm^(−1)to 7250 cm^(−1).Upon radiation with a 118 nm laser,signals corresponding to the cationic 2-EE(m/z=90)and dissociative ioniza-tion products(m/z=72,59,46,and 45)were detected.The action IR spectra,derived from the signal variations of 2-EE and its fragments upon IR radiation,display differences,suggest-ing vibrational mode selectivity in the dissociative ionization process.To complement the ex-perimental findings,we performed density functional theory calculations at the B3LYP-D3(BJ)/def2-TZVPP level to determine the structures and anharmonic IR spectra of neutral and cationic 2-EE.The computed spectra showed good agreement with the experimental re-sults. 展开更多
关键词 Gas phase infrared spectroscopy Neutral and cationic molecular structure Vi-brational mode selectivity
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MOF encapsulation derived slow-release oxygen species to enhance the activity and selectivity of methane selective oxidation:A transient DRIFTs Study
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作者 Ke-Xin Li Hao Yuan +1 位作者 Ralph T.Yang Zhun Hu 《Chinese Journal of Catalysis》 2025年第11期202-214,共13页
The methane selective oxidation was a"holy grail"reaction.However,peroxidation and low selectivity limited the application.Herein,we combined three Au contents with TiO_(2)in both encapsulation(xAu@TiO_(2))a... The methane selective oxidation was a"holy grail"reaction.However,peroxidation and low selectivity limited the application.Herein,we combined three Au contents with TiO_(2)in both encapsulation(xAu@TiO_(2))and surface-loaded(xAu/TiO_(2))ways by MOF derivation strategy,reported a catalyst 0.5Au@TiO_(2)exhibited a CH_(3)OH yield of 32.5μmol·g^(-1)·h^(-1)and a CH_(3)OH selectivity of 80.6%under catalytic conditions of only CH_(4),O_(2),and H_(2)O.Mechanically speaking,the catalytic activity was controlled by both electron-hole separation efficiency and core-shell structure.The interfacial contact between Au nanoparticles and TiO_(2)in xAu@TiO_(2)and xAu/TiO_(2)induced the formation of oxygen vacancies,with 0.5 Au content showing the highest oxygen vacancy concentration.At the same Au content,xAu@TiO_(2)generated more oxygen vacancies than xAu/TiO_(2).The oxygen vacancy acted as an effective electron cold trap,which enhanced the photogenerated carrier separation efficiency and thereby improved the catalytic activity.In-situ DRIFTs revealed that the isolated OH(non-hydrogen bond adsorption)were key species for the methane selective oxidation,playing a role in the activation of CH_(4)to^(*)CH_(3).However,an overabundance of isolated OH led to severe overoxidation.Fortunately,the core-shell structure over xAu@TiO_(2)provided a slow-release environment for isolated OH through the intermediate state of^(*)OH(hydrogen bond adsorption)to balance the formation rate and consumption rate of isolated OH,doubling the methanol yield and increasing the>29%selectivity.These results showed a new strategy for the control of the overoxidation rate via a strategy of MOF encapsulation followed by pyrolytic derivation for methane selective oxidation. 展开更多
关键词 Methane selective oxidation Metal-organic framework derived Reactive oxygen species modulation Hydrogen bonded adsoprotion hydroxyl groups
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踝关节有限元模型的特性及临床应用 被引量:1
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作者 张楠 孟庆华 鲍春雨 《中国组织工程研究》 北大核心 2026年第9期2343-2349,共7页
背景:踝关节是人体中最复杂的关节之一,包括腓骨、胫骨及距骨等骨性结构,以及韧带、肌肉和肌腱等软组织。有限元模型作为一种重要的工程分析技术,已广泛应用于生物工程研究的各个领域。然而,很少有文献介绍踝关节有限元模型的每个解剖... 背景:踝关节是人体中最复杂的关节之一,包括腓骨、胫骨及距骨等骨性结构,以及韧带、肌肉和肌腱等软组织。有限元模型作为一种重要的工程分析技术,已广泛应用于生物工程研究的各个领域。然而,很少有文献介绍踝关节有限元模型的每个解剖结构应选择什么样的材料性能,以满足不同的研究目的。目的:在前人踝关节有限元研究的基础上,总结踝关节有限元模型建模方法、材料特性、模型验证以及临床和康复应用。方法:检索PubMed数据库、中国知网,检索时限为2000-2024年,英文检索词为“ankle joint,finite elements,material selection,ligament injury,osteoarthritis等”;中文检索词为“踝关节,有限元,材料选择,韧带损伤,骨关节炎等”,对入选的71篇文献进行归纳总结。结果与结论:①踝关节结构复杂,准确的解剖结构和材料是建立仿真模型的基础;②踝关节的有限元建模可以深入了解踝关节的生物力学特性,开发新的置入材料,预测踝关节疾病,改进手术技术,并指导康复锻炼;③过去的研究大多没有考虑体温和关节液对模型的影响,未来需要解决这个问题;此外,踝关节作为下肢重要的负重关节,还可以进行屈曲、伸展和旋转活动,踝关节有限元模型模拟复杂运动将是未来研究的重点。 展开更多
关键词 踝关节 有限元 生物力学 材料选择 韧带损伤 骨关节炎
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“十四五”我国大白菜遗传育种研究进展 被引量:1
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作者 张凤兰 张斌 +7 位作者 苏同兵 于拴仓 余阳俊 张德双 赵岫云 汪维红 李佩荣 辛晓云 《中国蔬菜》 北大核心 2026年第1期1-13,共13页
“十四五”期间我国在大白菜远缘杂交、泛基因组和驯化演变等相关基础研究取得重大突破,对重要农艺性状的基因进行了定位、克隆和调控机制分析,开发了可用于辅助选择的分子标记;在大白菜种质资源搜集、鉴定、挖掘和创新利用上取得显著进... “十四五”期间我国在大白菜远缘杂交、泛基因组和驯化演变等相关基础研究取得重大突破,对重要农艺性状的基因进行了定位、克隆和调控机制分析,开发了可用于辅助选择的分子标记;在大白菜种质资源搜集、鉴定、挖掘和创新利用上取得显著进展,创制和培育出一批优异新种质和优质多抗新品种。本文对近5年我国在大白菜遗传育种领域取得的进展进行了梳理和总结,讨论分析了目前大白菜育种中存在的主要问题和未来的攻关方向。 展开更多
关键词 大白菜 遗传育种 种质创新 基因克隆/QTL定位 新品种选育 综述
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中国医疗机构药品评价与遴选快速指南(第三版)
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作者 赵志刚 董占军 刘建平 《医药导报》 北大核心 2026年第1期1-9,共9页
随着中国医药卫生行业不断发展,医疗机构药品评价与遴选的科学性、合规性要求显著提升。基于近年药学领域发展成果与国家药品政策调整方向,《中国医疗机构药品评价与遴选快速指南(第三版)》(简称《指南》)在第一、二版基础上,对药品的... 随着中国医药卫生行业不断发展,医疗机构药品评价与遴选的科学性、合规性要求显著提升。基于近年药学领域发展成果与国家药品政策调整方向,《中国医疗机构药品评价与遴选快速指南(第三版)》(简称《指南》)在第一、二版基础上,对药品的评价指标进行了修订与细化,一方面通过量化评分体系强化药品在医疗机构内的优先级区分度,确保评价标准与国家政策导向深度契合;另一方面进一步细化评分条目表述,更便于操作,降低临床应用中的执行难度。《指南》通过有效性(28分)、安全性(27分)、药学特性(27分)、经济性(10分)和其他属性(8分)5个维度对药品进行量化评分,促进药品评价重心回归临床价值,有助于医疗机构对药品进行客观遴选与评价。 展开更多
关键词 医疗机构 药品评价 药品遴选 快速指南
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一种高效安全的联邦学习隐私保护方案
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作者 宋成 樊源龙 《重庆邮电大学学报(自然科学版)》 北大核心 2026年第1期12-19,共8页
针对联邦学习过程中设备的地理位置、网络状态、存储能力、计算能力、参数交换等多方面差异导致通信效率低、安全性能得不到保障的问题,提出了一种高效的联邦学习数据聚合隐私保护方案。方案通过参与客户端分组并选取组长减少与服务器... 针对联邦学习过程中设备的地理位置、网络状态、存储能力、计算能力、参数交换等多方面差异导致通信效率低、安全性能得不到保障的问题,提出了一种高效的联邦学习数据聚合隐私保护方案。方案通过参与客户端分组并选取组长减少与服务器之间的直接交互次数,运用梯度压缩技术减少客户端上传的参数量,提高通信效率;引入可信第三方并设计高效的密钥协议对参与方上传的参数进行加密来确保隐私安全,每个用户能够独立验证服务器返回的聚合结果。安全性分析表明,提出的方案满足不可区分、数据隐私等安全性能;实验结果显示,方案的准确率较高并且通信开销与对比算法相比也有明显优势。 展开更多
关键词 联邦学习 隐私保护 组长选取 梯度选择 可验证聚合
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育种新时代水稻杂交育种技术与策略探讨
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作者 吕文彦 程海涛 +1 位作者 马兆惠 田淑华 《中国农业科学》 北大核心 2026年第2期233-238,共6页
随着时间与技术的发展,作物育种经历了1.0到4.0世代,正向育种5.0世代发展。目前,虽然育种3.0世代和育种4.0世代得到广泛重视,但只有育种2.0世代的杂交育种才能够使亲本实现全基因组重组,出现基因内和基因间大量的、复杂的和不可预见的互... 随着时间与技术的发展,作物育种经历了1.0到4.0世代,正向育种5.0世代发展。目前,虽然育种3.0世代和育种4.0世代得到广泛重视,但只有育种2.0世代的杂交育种才能够使亲本实现全基因组重组,出现基因内和基因间大量的、复杂的和不可预见的互作,可能这才是导致突破性性状产生的基础,因此,在育种新时代背景下,杂交育种依然占有重要地位。但目前,以水稻为例,在科学性和有效性方面,广大育种工作者在杂交育种操作上仍然存在提高的空间。为选育高产、优质、多抗品种,克服品种的同质化,水稻杂交育种应注意以下几点:(1)育种目标要结合当地的自然条件,协调有利性状组配,使高产、优质、多抗的目标性状与具体品种相结合,避免品种同质化。(2)由于F_(1)综合双亲优良性状且具有一定的杂种优势,可能是同一组合表现最好的世代,F_(1)综合表现不良,其后代很难出现符合育种目标的期望类型。因此,此世代应作为一个重点选择世代,有利于提高育种效率。(3)在育种早代,因为主要是进行世代的促进,为提高育种效能,应采取直播形式,从而节省土地和资源。而育种中代应与早代测验相结合,以增强预见性,进一步筛选组合,提高育种效率。(4)高世代选择时,应在田间筛选后,进一步在室内比较组合间的穗部性状,选出最优组合,以实现优中选优。(5)育种5.0世代的智能型品种就是能够适应广域环境的生态与生物因子,并能满足生产需要的广适性品种,由于作物生长环境条件的复杂性,为实现广适性育种目标,应对品种进行多年、多点的广泛鉴定。总之,通过优化杂交育种的田间操作和选择技术,会大大提高育种效率,为选育出突破性品种奠定基础。 展开更多
关键词 水稻 杂交育种 育种目标 选择技术 世代促进 广适性
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鸡粪菌移植关键技术研究进展
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作者 施寿荣 黎智华 张倩雲 《中国家禽》 北大核心 2026年第2期1-10,共10页
粪菌移植是指通过提取健康供体的肠道或粪便中的微生物,移植到受体肠道,重新构建受体肠道微生物群,从而改善受体的机体健康水平(如肠道健康、机体免疫力等),达到治疗疾病或提高受体生产性能的目的。移植供体的生长阶段、菌液的采集和处... 粪菌移植是指通过提取健康供体的肠道或粪便中的微生物,移植到受体肠道,重新构建受体肠道微生物群,从而改善受体的机体健康水平(如肠道健康、机体免疫力等),达到治疗疾病或提高受体生产性能的目的。移植供体的生长阶段、菌液的采集和处理方法(如微生物来源的选择、菌液稀释比例、滤过孔径、离心转速和保存方法)、受体的日龄以及是否进行抗生素预处理等指标均影响粪菌移植的效率。近年来,粪菌移植技术在鸡上已开展探索性的应用,但未形成较为统一的技术标准。文章对影响鸡粪菌移植效果的关键技术(供体和受体选择、粪菌来源、粪菌液的制备、粪菌移植方法、剂量和周期等)进行归纳总结,为建立鸡粪菌移植的标准化操作流程提供参考依据。 展开更多
关键词 粪菌移植 供体鸡选择 受体鸡选择 移植方法
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面向高光谱遥感图像的MMRI-Boruta特征选择算法
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作者 张婧 孔霄 +2 位作者 曹峰 张超 李德玉 《郑州大学学报(理学版)》 北大核心 2026年第1期72-77,共6页
高光谱遥感图像特征选择旨在从高维光谱特征集中选择最优光谱特征子集,以消除冗余光谱特征来提高高光谱遥感图像分析的效率和精度。由此提出了一种混合型特征选择算法MMRI-Boruta,该算法首先对过滤式MRI特征选择算法进行改进,通过引入... 高光谱遥感图像特征选择旨在从高维光谱特征集中选择最优光谱特征子集,以消除冗余光谱特征来提高高光谱遥感图像分析的效率和精度。由此提出了一种混合型特征选择算法MMRI-Boruta,该算法首先对过滤式MRI特征选择算法进行改进,通过引入方差定义新的特征重要性评价指标,然后利用封装式的Boruta算法实现特征子集的进一步优化。所提算法结合了过滤式和封装式两种特征选择算法的优点,更易于获取最优特征子集。为了验证该算法的有效性,使用了两个经典的高光谱遥感图像数据集Indian Pines和Salinas对算法的性能进行了测试,实验结果表明该算法优于对比算法。 展开更多
关键词 高光谱遥感图像 特征选择 互信息 相关性
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