Base-catalyzed nucleophilic substitution reactions ofβ-ketonitrile with azodicarboxylates have been developed.A series of disubstituted C—N coupling products were obtained in good to excellent yields under Et_(3)N c...Base-catalyzed nucleophilic substitution reactions ofβ-ketonitrile with azodicarboxylates have been developed.A series of disubstituted C—N coupling products were obtained in good to excellent yields under Et_(3)N catalysis.Monosubstitu-tion C—N bond formation reaction catalyzed by K_(2)CO_(3) also gave novel enol-based target products.This method is simple and mild,with good chemoselectivity,excellent substrate compatibility and tolerance for various functional groups,and achieves gram-scale synthesis.The reaction is a nucleophilic substitution process without the involvement of free radicals.展开更多
The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively red...The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively reduce C=C or C=O bonds while preserving other functional groups within the molecule.This approach serves as a critical strategy for the directional synthesis of high-value molecules.However,achieving such selectivity remains challenging due to the thermodynamic equilibrium and kinetic competition between C=O and C=C bonds inα,β-unsaturated systems.Consequently,constructing precisely targeted catalytic systems is essential to overcome these limitations,offering both fundamental scientific significance and industrial application potential.Metal-organic frameworks(MOFs)and their derivatives have emerged as innovative platforms for designing such systems,owing to their programmable topology,tunable pore microenvironments,spatially controllable active sites,and modifiable electronic structures.This review systematically summarizes the research progress of MOF-based catalysts for selec-tive hydrogenation ofα,β-unsaturated aldehydes/ketones in the last decade,with emphasis on the design strategy,conformational relationship,and catalytic mechanism,aiming to provide new ideas for the design of targeted catalyt-ic systems for the selective hydrogenation ofα,β-unsaturated aldehydes/ketones.展开更多
ZGH401 alloy was prepared under varying laser power levels and scanning speeds by the orthogonal test method using selective laser melting(SLM).The effect of different energy densities on microstructure and mechanical...ZGH401 alloy was prepared under varying laser power levels and scanning speeds by the orthogonal test method using selective laser melting(SLM).The effect of different energy densities on microstructure and mechanical properties of the formed alloy was investigated.The microstructure of ZGH401 was analyzed by scanning electron microscope,electron back-scattered diffraction,and electron probe microanalysis.The results show that the defects of the as-built ZGH401 are gradually reduced,the relative density is correspondingly enhanced with increasing the energy density,and the ultimate density can reach 99.6%.An increase in laser power leads to a corresponding rise in hardness of ZGH401,while a faster scanning speed reduces the residual stress in asbuilt ZGH401 samples.In addition,better tensile properties are achieved at room temperature due to more grain boundaries perpendicular to the build direction than parallel to the build direction.The precipitated phases are identified as carbides and Laves phases via chemical composition analysis,with fewer carbides observed at the molten pool boundaries than within the molten pools.展开更多
We report a robust pillar-layered metal-organic framework,Zn‑tfbdc‑dabco(tfbdc:tetrafluoroterephthal-ate,dabco:1,4-diazabicyclo[2.2.2]octane),featuring the fluorinated pore environment,for the preferential binding of ...We report a robust pillar-layered metal-organic framework,Zn‑tfbdc‑dabco(tfbdc:tetrafluoroterephthal-ate,dabco:1,4-diazabicyclo[2.2.2]octane),featuring the fluorinated pore environment,for the preferential binding of propane over propylene and thus highly inverse selective separation of propane/propylene mixture.The inverse propane-selective performance of Zn‑tfbdc‑dabco for the propane/propylene separation was validated by single-component gas adsorption isotherms,isosteric enthalpy of adsorption calculations,ideal adsorbed solution theory calculations,along with the breakthrough experiment.The customized fluorinated networks served as a propane-trap to form more interactions with the exposed hydrogen atoms of propane,as unveiled by the simulation studies at the molecular level.With the advantage of inverse propane-selective adsorption behavior,high adsorption capacity,good cycling stability,and low isosteric enthalpy of adsorption,Zn‑tfbdc‑dabco can be a promising candidate adsorbent for the challenging propane/propylene separation to realize one-step purification of the target propylene substance.展开更多
Bisphenol A(BPA)has threatened ecological safety and human health due to its endocrine disrupting effect and widely diffused in the environment.Peroxymonosulfate(PMS)based on oxidation technology exhibits good potenti...Bisphenol A(BPA)has threatened ecological safety and human health due to its endocrine disrupting effect and widely diffused in the environment.Peroxymonosulfate(PMS)based on oxidation technology exhibits good potential for environmental remediation whereas the highly efficient activator needs to be developed.Herein,the Bi OBr(BOB)was synthesized to efficiently activate PMS to remove 95.6%of BPA within 60 min.The observed rate constant of BPA removal in BOB/PMS system is 0.049 min^(-1),which is 60 and 148 times to that of the BOB and PMS processes separately and 129 times to the compared Bi OCl(BOC)/PMS system,respectively.Comparison experiments and analytic methods demonstrate that BOB with a larger content of oxygen vacancies(Ov)can act as the bridge of electron transfer between Bi^(3+)/Bi^(4+)with PMS to enhance the activation ability for PMS,resulting in the production of abundant reactive oxygen species(O_(2)^(·-)and ^(1)O_(2)).Additionally,the breakdown processes of BPA and the toxicity of its byproducts were uncovered,and the potential for actual water treatment was evaluated to confirm the detoxification,efficiency,stability and practical use of the BOB/PMS system for eliminating BPA.This study may widen the application of traditional semiconductors and develop the cost-effective PMS activation methods for environmental remediation.展开更多
Europe’s shift toward selective protectionism,particularly targeting China,undermines its commitment to free trade,threatens its industrial competitiveness,and ultimately jeopardizes European prosperity.
Iron-Vanadium(FeV)catalyst showed a unique catalytic activity for the selective oxidation of methanol to formaldehyde;however,due to its complex compositions,the identification of catalytic active sites still remains ...Iron-Vanadium(FeV)catalyst showed a unique catalytic activity for the selective oxidation of methanol to formaldehyde;however,due to its complex compositions,the identification of catalytic active sites still remains challenging,inhibiting the rational design of excellent FeV-based catalysts.Here,in this work,a series of FeV catalysts with various compositions,including FeVO_(4),isolated VO_(x),low-polymerized V_(n)O_(x),and crystalline V_(2)O_(5) were prepared by controlling the preparation conditions,and were applied to methanol oxidation to formaldehyde reaction.A FeV_(1.1) catalyst,which consisted of FeVO_(4) and low-polymerized V_(n)O_(x) species showed an excellent catalytic performance with a methanol conversion of 92.3%and a formaldehyde selectivity of 90.6%,which was comparable to that of conventional iron-molybdate catalyst.The results of CH_(3)OH-IR,O_(2) pulse and control experiments revealed a crucial synergistic effect between FeVO_(4) and low-polymerized V_(n)O_(x).It enhanced the oxygen supply capacity and suitable binding and adsorption strengths for formaldehyde intermediates,contributing to the high catalytic activity and formaldehyde selectivity.This study not only advances the understanding of FeV structure but also offers valuable guidelines for selective methanol oxidation to formaldehyde.展开更多
As the density of wireless networks increases globally, the vulnerability of overlapped dense wireless communications to interference by hidden nodes and denial-of-service (DoS) attacks is becoming more apparent. Ther...As the density of wireless networks increases globally, the vulnerability of overlapped dense wireless communications to interference by hidden nodes and denial-of-service (DoS) attacks is becoming more apparent. There exists a gap in research on the detection and response to attacks on Medium Access Control (MAC) mechanisms themselves, which would lead to service outages between nodes. Classifying exploitation and deceptive jamming attacks on control mechanisms is particularly challengingdue to their resemblance to normal heavy communication patterns. Accordingly, this paper proposes a machine learning-based selective attack mitigation model that detects DoS attacks on wireless networks by monitoring packet log data. Based on the type of detected attack, it implements effective corresponding mitigation techniques to restore performance to nodes whose availability has been compromised. Experimental results reveal that the accuracy of the proposed model is 14% higher than that of a baseline anomaly detection model. Further, the appropriate mitigation techniques selected by the proposed system based on the attack type improve the average throughput by more than 440% compared to the case without a response.展开更多
The efficient catalytic conversion of fossil-based low-carbon small molecules to oxygen-containing chemicals is an attractive research topic in the fields of energy and chemical engineering.The selective oxidation of ...The efficient catalytic conversion of fossil-based low-carbon small molecules to oxygen-containing chemicals is an attractive research topic in the fields of energy and chemical engineering.The selective oxidation of dimethyl ether(DME),which is derived from fossil resources,represents a promising approach to producing high-concentration formaldehyde with low energy consumption.However,there is still a lack of catalysts achieving satisfactory conversion of DME with high selectivity for formaldehyde under mild conditions.In this work,an efficient iron-molybdate(FeMo)catalyst was developed for the selective oxidation of DME to formaldehyde.The DME conversion of 84% was achieved with a superior formaldehyde selectivity(77%)at 300℃,a performance that is superior to all previously reported results.In an approximately 550 h continuous reaction,the catalyst maintained a conversion of 64% and a formaldehyde selectivity of 79%.Combined X-ray diffraction(XRD),Transmission electron microscope(TEM),Ultraviolet-visible spectroscopy(UV-Vis),Hydrogen temperature-programmed reduction(H_(2)-TPR),Fourier transform infrared(FT-IR)analyses,along with density functional theory(DFT)calculations,demonstrated that the excellent FeMo catalyst was composed of active Fe_(2)(MoO_(4))_(3)and MoO_(3)phases,and there was an interaction between them,which contributed to the efficient DME dissociation and smooth hydrogen spillover,leading to a superior DME conversion.With the support of DME/O_(2)pulse experiments,in-situ Raman,in-situ Dimethyl ether infrared spectroscopy(DME-IR)and DFT calculation results,a Mars-van Krevelen(MvK)reaction mechanism was proposed:DME was dissociated on the interface between Fe_(2)(MoO_(4))_(3)and MoO_(3)phases to form active methoxy species firstly,and it dehydrogenated to give hydrogen species;the generated hydrogen species smoothly spilled over from Fe_(2)(MoO_(4))_(3)to MoO_(3)enhanced by the interaction between Fe_(2)(MoO_(4))_(3)and MoO_(3);then the hydrogen species was consumed by MoO_(3),leading to a reduction of MoO_(3),and finally,the reduced MoO_(3)was re-oxidized by O_(2),returning to the initial state.These findings offer valuable insights not only for the development of efficient FeMo catalysts but also for elucidating the reaction mechanism involved in the oxidation of DME to formaldehyde,contributing to the optimized utilization of DME derived from fossil resources.展开更多
The potential of 2-amino-1-propanol(AP)as a novel depressant in selectively floating ilmenite from titanaugite under weakly acidic conditions was investigated.Micro-flotation results show that AP significantly reduces...The potential of 2-amino-1-propanol(AP)as a novel depressant in selectively floating ilmenite from titanaugite under weakly acidic conditions was investigated.Micro-flotation results show that AP significantly reduces the recovery of titanaugite while having no evident impact on ilmenite flotation.Subsequent bench-scale flotation tests further confirm a remarkable improvement in separation efficiency upon the introduction of AP.Contact angle and adsorption tests reveal a stronger affinity of AP towards the titanaugite surface in comparison to ilmenite.Zeta potential measurements and X-ray photoelectron spectroscopy(XPS)analyses exhibit favorable adsorption characteristics of AP on titanaugite,resulting from a synergy of electrostatic attraction and chemical interaction.In contrast,electrostatic repulsion hinders any significant interaction between AP and the ilmenite surface.These findings highlight the potential of AP as a highly efficient depressant for ilmenite flotation,paving the way for reduced reliance on sulfuric acid in the industry.展开更多
Recovery of rare earth elements(REEs)from bulk Nd-Fe-B scrap by chlorination with NH_(4)Cl as a chlorinating agent has been reported to be an energy efficient and environmentally friendly method.However,the reaction m...Recovery of rare earth elements(REEs)from bulk Nd-Fe-B scrap by chlorination with NH_(4)Cl as a chlorinating agent has been reported to be an energy efficient and environmentally friendly method.However,the reaction mechanism and phase evolution of the low-temperature selective chlorination process of Nd-Fe-B sludge are not clear.In this paper,we systematically investigated the lowtemperature selective chlorination process of Nd-Fe-B sludge with NH4Cl by combining thermokinetic theoretical calculations and experiments,and revealed its reaction mechanism.The phase evolution during chlorination was determined by X-ray diffraction(XRD),scanning electron microscopy(SEM)and ene rgy-dispersive X-ray spectroscopy(EDS)characterization as well as co mputational analysis of the phase stability diagram of the M-O-Cl system.To determine the optimum chlorination conditions,the effects of chlorinating agent dosage,reaction temperature and reaction time on the reaction were investigated.The results show that the rare earth components in Nd-Fe-B sludge are selectively chlorinated to RECl3and the formation of REOCl is avoided in the temperature range of 300-420℃,while the iron components are preferentially oxidized to Fe2O3.The selective chlorination reaction is consistent with the unreacted shrinking core model,and the rate-controlling step of the reaction is the internal diffusion process of NH4Cl through the transition layer of the reactant product to the surface of the Nd-Fe-B sludge.The complete chlorination of REEs is successfully achieved and 99.8%of REEs are selectively extracted into the leaching solution under optimal chlorination conditions(300℃,2.5 times of stoichiometric amount,4 h).展开更多
Co-associated rare earth elements(lanthanide and yttrium,REY)in coal and its by-products have been considered important potential nontraditional rare earth sources.In this study,a coal gangue sample collected from a c...Co-associated rare earth elements(lanthanide and yttrium,REY)in coal and its by-products have been considered important potential nontraditional rare earth sources.In this study,a coal gangue sample collected from a coal processing plant in Jinsha County of Guizhou Province,southwest China,was used as the research object.The content,modes of occurrence,and extraction(acid leaching after pretreatment of selective grinding,tailings discarding,and alkali roasting)of REY from the sample were analyzed.The result shows that the content of REY(1038.26μg/g)in pyrite and quartz is low but mainly enriched in kaolinite.Under the following conditions of a filling ratio of 40%(grinding media steel ball)and grinding time of 8 min,selective grinding pretreatment is applied to achieve 176.95μg/g(yield 24.08%)and 1104.93μg/g(yield 75.92%)of REY in+2 mm and-2 mm fractions,respectively.Thus,the-2 mm coal gangue fraction is selected,used as the feed,and roasted and leached with HCl.When Na_(2)CO_(3)and NaCl are separately used as roasting activators,the REY leaching ratios are 91.41%and 68.88%,respectively,under the optimum conditions.The contents of REY in the final leachate are 1010.02 and 761.08μg/g when Na_(2)CO_(3)and NaCl are used,respectively.The two REY contents are relatively higher than the impurity ions in the leachate,which facilitates further REY separation.The mechanism study reveals that high-temperature roasting increases the pore size and the total pore area of the gangue,which promotes leachate penetration and improves reaction efficiency.In addition,roasting facilitates the reaction between the sodium salt activator and kaolinite and other aluminosilicate minerals in the coal gangue to generate soluble salts,thus releasing REY into the solution.The appropriate roasting temperature transforms the activator into a molten state.Thus,the reaction between coal gangue and activator is a solid-liquid reaction rather than a solid-solid reaction,which improves the efficiency of the chemical reaction.展开更多
Additive manufacturing(AM)is an advanced production method for layer-by-layer fabrication,offering a paradigm shift in manufacturing.However,the sustainability of AM processes is poor,since suppliers recommend reusing...Additive manufacturing(AM)is an advanced production method for layer-by-layer fabrication,offering a paradigm shift in manufacturing.However,the sustainability of AM processes is poor,since suppliers recommend reusing 50%-70%of reprocessed powder,contributing to a significant increase in material disposal.To explore the possibility of fully reusing the polymeric material,we conduct a comprehensive characterisation of the powder particulates,in combination with analysis of the final prints.Utilizing optical and scanning electron microscopes,we statistically evaluate the size,morphology,and shape of the particles.Furthermore,tensile strength and deformation of printed bars is evaluated,showcasing the impact of aging on the print properties.The findings reveal that consecutive reuse of used powder significantly influences dimensional accuracy of the printed parts.We detect a 30.63%relative value of shrinkage after six printing iterations,which corresponds to an absolute shrinkage increase by 0.98%.This is significant considering the standard shrinkage for the material used is already 3.2%.Additionally,parts that are printed with reused material exhibit a small increase in elongation at yield,as well as an unexpected rise in tensile strength.Significant agglomeration of small particles is observed in the aged powder,since there are particles of less than 10μm,which are not found in the virgin powder.These results contribute to a better understanding of the issues related to the reusing of aged material,and offer invaluable insights for mitigating the environmental impact that is associated with material disposal in AM.展开更多
This paper investigates the selective maintenance o systems that perform multi-mission in succession. Selective maintenance is performed on systems with limited break time to improve the success of the next mission. I...This paper investigates the selective maintenance o systems that perform multi-mission in succession. Selective maintenance is performed on systems with limited break time to improve the success of the next mission. In general, the duration of the mission is stochastic. However, existing studies rarely take into account system availability and the repairpersons with different skill levels. To solve this problem, a new multi-mission selective maintenance and repairpersons assignment model with stochastic duration of the mission are developed. To maximize the minimum phase-mission reliability while meeting the minimum system availability, the model is transformed into an optimization problem subject to limited maintenance resources. The optimization is then realized using an analytical method based on a self-programming function and a Monte Carlo simulation method, respectively. Finally, the validity of the model and solution method approaches are verified by numerical arithmetic examples. Comparative and sensitivity analyses are made to provide proven recommendations for decision-makers.展开更多
Radioactive microspheres have demonstrated excellent therapeutic effects and good tolerance in the treatment of unresectable primary and secondary liver malignancies.This is attributed to precise embolization and pote...Radioactive microspheres have demonstrated excellent therapeutic effects and good tolerance in the treatment of unresectable primary and secondary liver malignancies.This is attributed to precise embolization and potent anti-tumor effect.However,certain limitations such as unstable loading,perfusion stasis,heterogeneous distribution,ectopic distribution,and insufficient dosage,restrict their clinical application.Herein,a novel personalized Y-90 carbon microsphere with high uniformity,high specific activity and high availability(^(90)Y-HUACM)is presented.It is synthesized through planar molecular complex adsorption and chemical deposition solidification.^(90)Y-HUACM exhibited controllable size,excellent biocompatibility,outstanding in vitro and in vivo stability.The radiolabeling efficiency of Y-90 exceeded 99%and the leaching rate of Y-90 is far below 0.1%.Furthermore,the excellent anti-tumor effect,nuclide loading stability,anti-reflux characteristics,precise embolization,and biosafety of^(90)Y-HUACM were validated in a rabbit VX2liver tumor model.In summary,this new,high-performance,and customizable radioactive microsphere provides a superior choice for selective internal radiation treatment of advanced liver cancer is expected to be rapidly applied in clinical practice.展开更多
The photocatalytic selective oxidation of biomass-derived 5-hydroxymethylfurfural(HMF)offers a sustainable alternative to thermal catalysis.However,the efficiency of this process is significantly limited by inadequate...The photocatalytic selective oxidation of biomass-derived 5-hydroxymethylfurfural(HMF)offers a sustainable alternative to thermal catalysis.However,the efficiency of this process is significantly limited by inadequate light absorption efficiency and the rapid recombination of photogenerated charge carriers in conventional photocatalysts.Herein,we developed a Co_(3)O_(4)/ZnIn_(2)S_(4)(Co_(3)O_(4)/ZIS)photocatalyst,in which Co_(3)O_(4)functions as a multifunctional cocatalyst.This photocatalyst significantly enhances the chemisorption and activation of HMF molecules through interfacial oxygen-hydroxyl interactions.Additionally,the incorporation of narrow-band gap Co_(3)O_(4)broadens the optical absorption range of the composite photocatalyst.Besides,integrating Co_(3)O_(4)with ZnIn_(2)S_(4)leads to a 5.9-fold increase in charge separation efficiency compared to pristine ZnIn_(2)S_(4).The optimized Co_(3)O_(4)/ZIS-3 photocatalyst(3 wt% Co_(3)O_(4)loading)exhibits exceptional selectivity and yield for 2,5-diformylfuran(DFF)under visible light irradiation,achieving 70.4%DFF selectivity with a 5.4-fold enhancement compared to pristine ZnIn_(2)S_(4).Scavenger experiments and electron spin resonance(ESR)spectroscopy indicate that superoxide radicals(O_(2)^(-))and h^(+)are the main active species driving the photocatalytic oxidation of HMF.Molecular simulations reveal that the activation of HMF and the transformation of the intermediate^(*)MF to^(*)DFF are more favorable over the Co_(3)O_(4)/ZIS composite due to lower activation barriers compared to those over ZnIn_(2)S_(4).Through this work,we aim to design highly efficient and affordable photocatalysts for biomass valorization and contribute valuable insights into the mechanisms of photocatalytic oxidation of HMF.展开更多
BACKGROUND Traumatic brain injury(TBI)poses a considerable risk to human health.After TBI,individuals are susceptible to a range of psychiatric disorders,with depression being a primary complication.Selective serotoni...BACKGROUND Traumatic brain injury(TBI)poses a considerable risk to human health.After TBI,individuals are susceptible to a range of psychiatric disorders,with depression being a primary complication.Selective serotonin reuptake inhibitors(SSRIs)are frequently used in the treatment of depression;however,their efficacy in addressing major depressive disorder(MDD)in adults following TBI remains uncertain.AIM To investigate the efficacy of SSRIs in the treatment of MDD after TBI.METHODS A comprehensive search across multiple databases was conducted following the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement,encompassing studies published until May 2024.This review focused on studies that examined the efficacy of SSRIs in the treatment of MDD following TBI.Studies were assessed based sample size,treatment duration,treatment methodologies,severity of brain injury,assessment techniques,and drug response.A random-effects model was used to derive the summary effect size.RESULTS Eight studies compared the reduction in depression scores in patients with MDD after TBI and SSRI treatment.The eight studies did not exhibit heterogeneity(I^(2)=38%).The depression score for MDD after TBI in the SSRI group decreased more than that in the control group[odds ratio(OR)1.68,95%CI:1.09-2.58,P=0.02].The adverse reactions after treatment included diarrhea,dizziness,dry mouth,nausea,or vomiting.There was no difference in the incidence of adverse reactions after treatment between the two groups(OR 1.16,95%CI:0.78-1.73,P=0.46).These studies did not show significant heterogeneity(I^(2)=44%).CONCLUSION SSRIs may be effective in treating patients with MDD after TBI.Adequately powered,randomized,controlled trials are required to confirm these findings.展开更多
Background:A thorough examination of the physicochemical properties,higher-order structure,subcellular localization,and selective pressure of the cytochrome c oxidase subunit I(COX1)protein of the endemic species Eoth...Background:A thorough examination of the physicochemical properties,higher-order structure,subcellular localization,and selective pressure of the cytochrome c oxidase subunit I(COX1)protein of the endemic species Eothenomys miletus(E.miletus)in the Hengduan Mountains provides further insights into molecular characteristics and function of the COX1 gene in E.miletus.Method:The physicochemical properties and higher-order structure of the COX1 protein of E.miletus were analyzed using bioinformatics software.Subsequently,a phylogenetic tree was constructed using Mega 7.0 software based on the COX1 gene from 19 species of the Arvicolinae subfamily and 3 species of the Muridae.Selection pressure analysis was performed using the PAML 4.7 software and the Datamonkey online website.Results:The COX1 protein of E.miletus comprises/consists of 514 amino acids,with leucine(Leu/L)being the most prevalent amino acid(11.5%).This hydrophilic protein contains 42 phosphorylation sites and 4 N-glycosylation sites.It possesses a transmembrane domain and lacks signal peptide distribution,thus classifying it as a non-GPI-anchored protein.The secondary structure of the COX1 protein consists ofα-helices(36.77%),random coils(33.85%),and extended chains,a composition consistent with/findings that align with its tertiary structure.Significant genetic differentiation exists among species within the Arvicolinae subfamily,a finding consistent with morphological identification results.The COX1 gene in Arvicolinae species exhibits purifying selection.Conclusion:This study analyzed the physicochemical properties of the COX1 protein in E.miletus.Phylogenetic and selection pressure analyses reveal significant genetic divergence among Arvicolinae species,and demonstrate that the COX1 gene is evolutionarily conserved within the Arvicolinae subfamily.展开更多
Neodymium-iron-boron(Nd-Fe-B)sludge is an important secondary resource of rare-earth elements(REEs).However,the state-of-the-art recycling method,i.e.,HCl-preferential dissolution faces challenges such as slow leachin...Neodymium-iron-boron(Nd-Fe-B)sludge is an important secondary resource of rare-earth elements(REEs).However,the state-of-the-art recycling method,i.e.,HCl-preferential dissolution faces challenges such as slow leaching kinetics,excessive chemical consumption and wastewater generation.In this work,the in situ anodic leaching of Nd-Fe-B sludge was developed to selectively recover REEs with high efficiency.The leaching rates of the REEs are 2.4-9.0 times higher using the in situ anodic leaching at the current density from 10 to 40 mA/cm^(2)than using conventional chemical leaching under the maintained pH of 3.7.Mechanism studies reveal that the anode-generated H~+plays the key role during the in situ anodic leaching process that locally increases the H^(+)concentration at the interface of sludge particles,accele rating the leaching kinetics.By achieving a total leaching efficiency of Nd-Fe-B sludge close to 100%and the Fe deposition efficiency in the range of 70.9%-74.3%,selective leaching of REEs is successfully realized and thus largely reduces chemical consumption.Additionally,a two-step recycling route involving electrolysis-selective precipitation was proposed that enables a stable REEs recovery of 92.2%with recyclable electrolyte.This study provides a novel and environmentally-friendly strategy for the efficient recovery of REEs from secondary resources.展开更多
Supramolecular prodrug vesicles(H-4⊃B-2@MB)with selective antibacterial activity have been successfully constructed.Specifically,a natural antibiotic prodrug(B-2)with glutathione(GSH)-responsiveness was synthesized.Th...Supramolecular prodrug vesicles(H-4⊃B-2@MB)with selective antibacterial activity have been successfully constructed.Specifically,a natural antibiotic prodrug(B-2)with glutathione(GSH)-responsiveness was synthesized.The hydrophobic interaction between B-2 and a novel water-soluble cavitand with deep cavity(H-4)resulted in the formation of a host-vip complex,which further self-assembled into supramolecular vesicles.The formed vesicles could effectively encapsulate the photosensitizer methylene blue(MB),enabling co-delivery of antibiotics and photosensitizers in the presence of GSH.Moreover,upon excitation at 630 nm,the photosensitizers generate reactive oxygen species(ROS),effectively eradicating E.coli through combined chemo-photodynamic therapy.Considering that GSH is predominantly present in Gram-negative bacteria such as E.coli,this strategy exhibits substantial potential for selectively inhibiting bacteria characterized by high GSH levels to regulate bacterial colony equilibrium.展开更多
文摘Base-catalyzed nucleophilic substitution reactions ofβ-ketonitrile with azodicarboxylates have been developed.A series of disubstituted C—N coupling products were obtained in good to excellent yields under Et_(3)N catalysis.Monosubstitu-tion C—N bond formation reaction catalyzed by K_(2)CO_(3) also gave novel enol-based target products.This method is simple and mild,with good chemoselectivity,excellent substrate compatibility and tolerance for various functional groups,and achieves gram-scale synthesis.The reaction is a nucleophilic substitution process without the involvement of free radicals.
文摘The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively reduce C=C or C=O bonds while preserving other functional groups within the molecule.This approach serves as a critical strategy for the directional synthesis of high-value molecules.However,achieving such selectivity remains challenging due to the thermodynamic equilibrium and kinetic competition between C=O and C=C bonds inα,β-unsaturated systems.Consequently,constructing precisely targeted catalytic systems is essential to overcome these limitations,offering both fundamental scientific significance and industrial application potential.Metal-organic frameworks(MOFs)and their derivatives have emerged as innovative platforms for designing such systems,owing to their programmable topology,tunable pore microenvironments,spatially controllable active sites,and modifiable electronic structures.This review systematically summarizes the research progress of MOF-based catalysts for selec-tive hydrogenation ofα,β-unsaturated aldehydes/ketones in the last decade,with emphasis on the design strategy,conformational relationship,and catalytic mechanism,aiming to provide new ideas for the design of targeted catalyt-ic systems for the selective hydrogenation ofα,β-unsaturated aldehydes/ketones.
基金National Defense Science and Technology Project Management Center(2021-JCJQ-JJ-0092)。
文摘ZGH401 alloy was prepared under varying laser power levels and scanning speeds by the orthogonal test method using selective laser melting(SLM).The effect of different energy densities on microstructure and mechanical properties of the formed alloy was investigated.The microstructure of ZGH401 was analyzed by scanning electron microscope,electron back-scattered diffraction,and electron probe microanalysis.The results show that the defects of the as-built ZGH401 are gradually reduced,the relative density is correspondingly enhanced with increasing the energy density,and the ultimate density can reach 99.6%.An increase in laser power leads to a corresponding rise in hardness of ZGH401,while a faster scanning speed reduces the residual stress in asbuilt ZGH401 samples.In addition,better tensile properties are achieved at room temperature due to more grain boundaries perpendicular to the build direction than parallel to the build direction.The precipitated phases are identified as carbides and Laves phases via chemical composition analysis,with fewer carbides observed at the molten pool boundaries than within the molten pools.
文摘We report a robust pillar-layered metal-organic framework,Zn‑tfbdc‑dabco(tfbdc:tetrafluoroterephthal-ate,dabco:1,4-diazabicyclo[2.2.2]octane),featuring the fluorinated pore environment,for the preferential binding of propane over propylene and thus highly inverse selective separation of propane/propylene mixture.The inverse propane-selective performance of Zn‑tfbdc‑dabco for the propane/propylene separation was validated by single-component gas adsorption isotherms,isosteric enthalpy of adsorption calculations,ideal adsorbed solution theory calculations,along with the breakthrough experiment.The customized fluorinated networks served as a propane-trap to form more interactions with the exposed hydrogen atoms of propane,as unveiled by the simulation studies at the molecular level.With the advantage of inverse propane-selective adsorption behavior,high adsorption capacity,good cycling stability,and low isosteric enthalpy of adsorption,Zn‑tfbdc‑dabco can be a promising candidate adsorbent for the challenging propane/propylene separation to realize one-step purification of the target propylene substance.
基金financially supported by the National Key Research and Development Program of China(No.2022YFC3703103)National Natural Science Foundation of China(Nos.22206053,42277427)the Guangzhou Science and Technology Plan Project(No.2024A04J4058)。
文摘Bisphenol A(BPA)has threatened ecological safety and human health due to its endocrine disrupting effect and widely diffused in the environment.Peroxymonosulfate(PMS)based on oxidation technology exhibits good potential for environmental remediation whereas the highly efficient activator needs to be developed.Herein,the Bi OBr(BOB)was synthesized to efficiently activate PMS to remove 95.6%of BPA within 60 min.The observed rate constant of BPA removal in BOB/PMS system is 0.049 min^(-1),which is 60 and 148 times to that of the BOB and PMS processes separately and 129 times to the compared Bi OCl(BOC)/PMS system,respectively.Comparison experiments and analytic methods demonstrate that BOB with a larger content of oxygen vacancies(Ov)can act as the bridge of electron transfer between Bi^(3+)/Bi^(4+)with PMS to enhance the activation ability for PMS,resulting in the production of abundant reactive oxygen species(O_(2)^(·-)and ^(1)O_(2)).Additionally,the breakdown processes of BPA and the toxicity of its byproducts were uncovered,and the potential for actual water treatment was evaluated to confirm the detoxification,efficiency,stability and practical use of the BOB/PMS system for eliminating BPA.This study may widen the application of traditional semiconductors and develop the cost-effective PMS activation methods for environmental remediation.
文摘Europe’s shift toward selective protectionism,particularly targeting China,undermines its commitment to free trade,threatens its industrial competitiveness,and ultimately jeopardizes European prosperity.
文摘Iron-Vanadium(FeV)catalyst showed a unique catalytic activity for the selective oxidation of methanol to formaldehyde;however,due to its complex compositions,the identification of catalytic active sites still remains challenging,inhibiting the rational design of excellent FeV-based catalysts.Here,in this work,a series of FeV catalysts with various compositions,including FeVO_(4),isolated VO_(x),low-polymerized V_(n)O_(x),and crystalline V_(2)O_(5) were prepared by controlling the preparation conditions,and were applied to methanol oxidation to formaldehyde reaction.A FeV_(1.1) catalyst,which consisted of FeVO_(4) and low-polymerized V_(n)O_(x) species showed an excellent catalytic performance with a methanol conversion of 92.3%and a formaldehyde selectivity of 90.6%,which was comparable to that of conventional iron-molybdate catalyst.The results of CH_(3)OH-IR,O_(2) pulse and control experiments revealed a crucial synergistic effect between FeVO_(4) and low-polymerized V_(n)O_(x).It enhanced the oxygen supply capacity and suitable binding and adsorption strengths for formaldehyde intermediates,contributing to the high catalytic activity and formaldehyde selectivity.This study not only advances the understanding of FeV structure but also offers valuable guidelines for selective methanol oxidation to formaldehyde.
基金supported by the Ministry of Trade,Industry and Energy(MOTIE)under Training Industrial Security Specialist for High-Tech Industry(RS-2024-00415520)supervised by the Korea Institute for Advancement of Technology(KIAT)the Ministry of Science and ICT(MSIT)under the ICT Challenge and Advanced Network of HRD(ICAN)Program(No.IITP-2022-RS-2022-00156310)supervised by the Institute of Information&Communication Technology Planning&Evaluation(IITP).
文摘As the density of wireless networks increases globally, the vulnerability of overlapped dense wireless communications to interference by hidden nodes and denial-of-service (DoS) attacks is becoming more apparent. There exists a gap in research on the detection and response to attacks on Medium Access Control (MAC) mechanisms themselves, which would lead to service outages between nodes. Classifying exploitation and deceptive jamming attacks on control mechanisms is particularly challengingdue to their resemblance to normal heavy communication patterns. Accordingly, this paper proposes a machine learning-based selective attack mitigation model that detects DoS attacks on wireless networks by monitoring packet log data. Based on the type of detected attack, it implements effective corresponding mitigation techniques to restore performance to nodes whose availability has been compromised. Experimental results reveal that the accuracy of the proposed model is 14% higher than that of a baseline anomaly detection model. Further, the appropriate mitigation techniques selected by the proposed system based on the attack type improve the average throughput by more than 440% compared to the case without a response.
基金supported by the National Natural Science Foundation of China(U23A2088,22025206)the Dalian Innovation Support Plan for High Level Talents(2022RG13)+2 种基金DICP(Grant:DICP I202453,DICP I202234)the Fundamental Research Funds for the Central Universities(20720220008)support of the Liaoning Key Laboratory of Biomass Conversion for Energy and Material。
文摘The efficient catalytic conversion of fossil-based low-carbon small molecules to oxygen-containing chemicals is an attractive research topic in the fields of energy and chemical engineering.The selective oxidation of dimethyl ether(DME),which is derived from fossil resources,represents a promising approach to producing high-concentration formaldehyde with low energy consumption.However,there is still a lack of catalysts achieving satisfactory conversion of DME with high selectivity for formaldehyde under mild conditions.In this work,an efficient iron-molybdate(FeMo)catalyst was developed for the selective oxidation of DME to formaldehyde.The DME conversion of 84% was achieved with a superior formaldehyde selectivity(77%)at 300℃,a performance that is superior to all previously reported results.In an approximately 550 h continuous reaction,the catalyst maintained a conversion of 64% and a formaldehyde selectivity of 79%.Combined X-ray diffraction(XRD),Transmission electron microscope(TEM),Ultraviolet-visible spectroscopy(UV-Vis),Hydrogen temperature-programmed reduction(H_(2)-TPR),Fourier transform infrared(FT-IR)analyses,along with density functional theory(DFT)calculations,demonstrated that the excellent FeMo catalyst was composed of active Fe_(2)(MoO_(4))_(3)and MoO_(3)phases,and there was an interaction between them,which contributed to the efficient DME dissociation and smooth hydrogen spillover,leading to a superior DME conversion.With the support of DME/O_(2)pulse experiments,in-situ Raman,in-situ Dimethyl ether infrared spectroscopy(DME-IR)and DFT calculation results,a Mars-van Krevelen(MvK)reaction mechanism was proposed:DME was dissociated on the interface between Fe_(2)(MoO_(4))_(3)and MoO_(3)phases to form active methoxy species firstly,and it dehydrogenated to give hydrogen species;the generated hydrogen species smoothly spilled over from Fe_(2)(MoO_(4))_(3)to MoO_(3)enhanced by the interaction between Fe_(2)(MoO_(4))_(3)and MoO_(3);then the hydrogen species was consumed by MoO_(3),leading to a reduction of MoO_(3),and finally,the reduced MoO_(3)was re-oxidized by O_(2),returning to the initial state.These findings offer valuable insights not only for the development of efficient FeMo catalysts but also for elucidating the reaction mechanism involved in the oxidation of DME to formaldehyde,contributing to the optimized utilization of DME derived from fossil resources.
基金supported by the National Key Research and Development Program of China(No.2019YFC1803501)the National Natural Science Foundation of China(No.52074357)+2 种基金the Natural Science Foundation of Hunan Province,China(No.2022JJ30713)the Vanadium Titanium Union Foundationthe Project of Technology Innovation Center for Comprehensive Utilization of Strategic Mineral Resources,Ministry of Natural Resources,China。
文摘The potential of 2-amino-1-propanol(AP)as a novel depressant in selectively floating ilmenite from titanaugite under weakly acidic conditions was investigated.Micro-flotation results show that AP significantly reduces the recovery of titanaugite while having no evident impact on ilmenite flotation.Subsequent bench-scale flotation tests further confirm a remarkable improvement in separation efficiency upon the introduction of AP.Contact angle and adsorption tests reveal a stronger affinity of AP towards the titanaugite surface in comparison to ilmenite.Zeta potential measurements and X-ray photoelectron spectroscopy(XPS)analyses exhibit favorable adsorption characteristics of AP on titanaugite,resulting from a synergy of electrostatic attraction and chemical interaction.In contrast,electrostatic repulsion hinders any significant interaction between AP and the ilmenite surface.These findings highlight the potential of AP as a highly efficient depressant for ilmenite flotation,paving the way for reduced reliance on sulfuric acid in the industry.
基金Project supported by the National Natural Science Foundation of China(52261037,52401251)Key Research Project of Jiangxi Province(20203ABC28W006)+2 种基金the Research Fund of Key Laboratory of Rare Earths,Chinese Academy of SciencesKey Laboratory of Ionic Rare Earth Re sources and Environment,Ministry of Natural Resources of the People's Republic of China(2022IRERE302)the Ganzhou Science and Technology Innovation Empowerment Youth"Jie bang Gua shuai"Project。
文摘Recovery of rare earth elements(REEs)from bulk Nd-Fe-B scrap by chlorination with NH_(4)Cl as a chlorinating agent has been reported to be an energy efficient and environmentally friendly method.However,the reaction mechanism and phase evolution of the low-temperature selective chlorination process of Nd-Fe-B sludge are not clear.In this paper,we systematically investigated the lowtemperature selective chlorination process of Nd-Fe-B sludge with NH4Cl by combining thermokinetic theoretical calculations and experiments,and revealed its reaction mechanism.The phase evolution during chlorination was determined by X-ray diffraction(XRD),scanning electron microscopy(SEM)and ene rgy-dispersive X-ray spectroscopy(EDS)characterization as well as co mputational analysis of the phase stability diagram of the M-O-Cl system.To determine the optimum chlorination conditions,the effects of chlorinating agent dosage,reaction temperature and reaction time on the reaction were investigated.The results show that the rare earth components in Nd-Fe-B sludge are selectively chlorinated to RECl3and the formation of REOCl is avoided in the temperature range of 300-420℃,while the iron components are preferentially oxidized to Fe2O3.The selective chlorination reaction is consistent with the unreacted shrinking core model,and the rate-controlling step of the reaction is the internal diffusion process of NH4Cl through the transition layer of the reactant product to the surface of the Nd-Fe-B sludge.The complete chlorination of REEs is successfully achieved and 99.8%of REEs are selectively extracted into the leaching solution under optimal chlorination conditions(300℃,2.5 times of stoichiometric amount,4 h).
基金Project supported by the National Natural Science Foundation of China(51964009)。
文摘Co-associated rare earth elements(lanthanide and yttrium,REY)in coal and its by-products have been considered important potential nontraditional rare earth sources.In this study,a coal gangue sample collected from a coal processing plant in Jinsha County of Guizhou Province,southwest China,was used as the research object.The content,modes of occurrence,and extraction(acid leaching after pretreatment of selective grinding,tailings discarding,and alkali roasting)of REY from the sample were analyzed.The result shows that the content of REY(1038.26μg/g)in pyrite and quartz is low but mainly enriched in kaolinite.Under the following conditions of a filling ratio of 40%(grinding media steel ball)and grinding time of 8 min,selective grinding pretreatment is applied to achieve 176.95μg/g(yield 24.08%)and 1104.93μg/g(yield 75.92%)of REY in+2 mm and-2 mm fractions,respectively.Thus,the-2 mm coal gangue fraction is selected,used as the feed,and roasted and leached with HCl.When Na_(2)CO_(3)and NaCl are separately used as roasting activators,the REY leaching ratios are 91.41%and 68.88%,respectively,under the optimum conditions.The contents of REY in the final leachate are 1010.02 and 761.08μg/g when Na_(2)CO_(3)and NaCl are used,respectively.The two REY contents are relatively higher than the impurity ions in the leachate,which facilitates further REY separation.The mechanism study reveals that high-temperature roasting increases the pore size and the total pore area of the gangue,which promotes leachate penetration and improves reaction efficiency.In addition,roasting facilitates the reaction between the sodium salt activator and kaolinite and other aluminosilicate minerals in the coal gangue to generate soluble salts,thus releasing REY into the solution.The appropriate roasting temperature transforms the activator into a molten state.Thus,the reaction between coal gangue and activator is a solid-liquid reaction rather than a solid-solid reaction,which improves the efficiency of the chemical reaction.
文摘Additive manufacturing(AM)is an advanced production method for layer-by-layer fabrication,offering a paradigm shift in manufacturing.However,the sustainability of AM processes is poor,since suppliers recommend reusing 50%-70%of reprocessed powder,contributing to a significant increase in material disposal.To explore the possibility of fully reusing the polymeric material,we conduct a comprehensive characterisation of the powder particulates,in combination with analysis of the final prints.Utilizing optical and scanning electron microscopes,we statistically evaluate the size,morphology,and shape of the particles.Furthermore,tensile strength and deformation of printed bars is evaluated,showcasing the impact of aging on the print properties.The findings reveal that consecutive reuse of used powder significantly influences dimensional accuracy of the printed parts.We detect a 30.63%relative value of shrinkage after six printing iterations,which corresponds to an absolute shrinkage increase by 0.98%.This is significant considering the standard shrinkage for the material used is already 3.2%.Additionally,parts that are printed with reused material exhibit a small increase in elongation at yield,as well as an unexpected rise in tensile strength.Significant agglomeration of small particles is observed in the aged powder,since there are particles of less than 10μm,which are not found in the virgin powder.These results contribute to a better understanding of the issues related to the reusing of aged material,and offer invaluable insights for mitigating the environmental impact that is associated with material disposal in AM.
文摘This paper investigates the selective maintenance o systems that perform multi-mission in succession. Selective maintenance is performed on systems with limited break time to improve the success of the next mission. In general, the duration of the mission is stochastic. However, existing studies rarely take into account system availability and the repairpersons with different skill levels. To solve this problem, a new multi-mission selective maintenance and repairpersons assignment model with stochastic duration of the mission are developed. To maximize the minimum phase-mission reliability while meeting the minimum system availability, the model is transformed into an optimization problem subject to limited maintenance resources. The optimization is then realized using an analytical method based on a self-programming function and a Monte Carlo simulation method, respectively. Finally, the validity of the model and solution method approaches are verified by numerical arithmetic examples. Comparative and sensitivity analyses are made to provide proven recommendations for decision-makers.
基金supported by the National Major Scientific and Technological Special Project for“Significant New Drugs Development”(No.2018ZX09201018–028)the nuclear energy development projects of China during the 13thFive Year Plan periodthe key research and development project of the Sichuan Provincial Department of Science and Technology(No.18ZDYF1466)。
文摘Radioactive microspheres have demonstrated excellent therapeutic effects and good tolerance in the treatment of unresectable primary and secondary liver malignancies.This is attributed to precise embolization and potent anti-tumor effect.However,certain limitations such as unstable loading,perfusion stasis,heterogeneous distribution,ectopic distribution,and insufficient dosage,restrict their clinical application.Herein,a novel personalized Y-90 carbon microsphere with high uniformity,high specific activity and high availability(^(90)Y-HUACM)is presented.It is synthesized through planar molecular complex adsorption and chemical deposition solidification.^(90)Y-HUACM exhibited controllable size,excellent biocompatibility,outstanding in vitro and in vivo stability.The radiolabeling efficiency of Y-90 exceeded 99%and the leaching rate of Y-90 is far below 0.1%.Furthermore,the excellent anti-tumor effect,nuclide loading stability,anti-reflux characteristics,precise embolization,and biosafety of^(90)Y-HUACM were validated in a rabbit VX2liver tumor model.In summary,this new,high-performance,and customizable radioactive microsphere provides a superior choice for selective internal radiation treatment of advanced liver cancer is expected to be rapidly applied in clinical practice.
基金financially supported by the National Key Research and Development Program of China(No.2022YFB3805400)the National Natural Science Foundation of China(No.22178297,No.22478327)+3 种基金the Science and Technology Innovation Program of Hunan Province(No.2024RC9009)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDC04010100)the Provincial Natural Science Foundation of Hunan(No.2024JJ5371)the Scientific Research Fund of Hunan Provincial Education Department(No.24A0107)。
文摘The photocatalytic selective oxidation of biomass-derived 5-hydroxymethylfurfural(HMF)offers a sustainable alternative to thermal catalysis.However,the efficiency of this process is significantly limited by inadequate light absorption efficiency and the rapid recombination of photogenerated charge carriers in conventional photocatalysts.Herein,we developed a Co_(3)O_(4)/ZnIn_(2)S_(4)(Co_(3)O_(4)/ZIS)photocatalyst,in which Co_(3)O_(4)functions as a multifunctional cocatalyst.This photocatalyst significantly enhances the chemisorption and activation of HMF molecules through interfacial oxygen-hydroxyl interactions.Additionally,the incorporation of narrow-band gap Co_(3)O_(4)broadens the optical absorption range of the composite photocatalyst.Besides,integrating Co_(3)O_(4)with ZnIn_(2)S_(4)leads to a 5.9-fold increase in charge separation efficiency compared to pristine ZnIn_(2)S_(4).The optimized Co_(3)O_(4)/ZIS-3 photocatalyst(3 wt% Co_(3)O_(4)loading)exhibits exceptional selectivity and yield for 2,5-diformylfuran(DFF)under visible light irradiation,achieving 70.4%DFF selectivity with a 5.4-fold enhancement compared to pristine ZnIn_(2)S_(4).Scavenger experiments and electron spin resonance(ESR)spectroscopy indicate that superoxide radicals(O_(2)^(-))and h^(+)are the main active species driving the photocatalytic oxidation of HMF.Molecular simulations reveal that the activation of HMF and the transformation of the intermediate^(*)MF to^(*)DFF are more favorable over the Co_(3)O_(4)/ZIS composite due to lower activation barriers compared to those over ZnIn_(2)S_(4).Through this work,we aim to design highly efficient and affordable photocatalysts for biomass valorization and contribute valuable insights into the mechanisms of photocatalytic oxidation of HMF.
文摘BACKGROUND Traumatic brain injury(TBI)poses a considerable risk to human health.After TBI,individuals are susceptible to a range of psychiatric disorders,with depression being a primary complication.Selective serotonin reuptake inhibitors(SSRIs)are frequently used in the treatment of depression;however,their efficacy in addressing major depressive disorder(MDD)in adults following TBI remains uncertain.AIM To investigate the efficacy of SSRIs in the treatment of MDD after TBI.METHODS A comprehensive search across multiple databases was conducted following the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement,encompassing studies published until May 2024.This review focused on studies that examined the efficacy of SSRIs in the treatment of MDD following TBI.Studies were assessed based sample size,treatment duration,treatment methodologies,severity of brain injury,assessment techniques,and drug response.A random-effects model was used to derive the summary effect size.RESULTS Eight studies compared the reduction in depression scores in patients with MDD after TBI and SSRI treatment.The eight studies did not exhibit heterogeneity(I^(2)=38%).The depression score for MDD after TBI in the SSRI group decreased more than that in the control group[odds ratio(OR)1.68,95%CI:1.09-2.58,P=0.02].The adverse reactions after treatment included diarrhea,dizziness,dry mouth,nausea,or vomiting.There was no difference in the incidence of adverse reactions after treatment between the two groups(OR 1.16,95%CI:0.78-1.73,P=0.46).These studies did not show significant heterogeneity(I^(2)=44%).CONCLUSION SSRIs may be effective in treating patients with MDD after TBI.Adequately powered,randomized,controlled trials are required to confirm these findings.
基金supported by the National Natural Science Foundation of China(32160254)Yunnan Fundamental Research Projects(202401AS070039).
文摘Background:A thorough examination of the physicochemical properties,higher-order structure,subcellular localization,and selective pressure of the cytochrome c oxidase subunit I(COX1)protein of the endemic species Eothenomys miletus(E.miletus)in the Hengduan Mountains provides further insights into molecular characteristics and function of the COX1 gene in E.miletus.Method:The physicochemical properties and higher-order structure of the COX1 protein of E.miletus were analyzed using bioinformatics software.Subsequently,a phylogenetic tree was constructed using Mega 7.0 software based on the COX1 gene from 19 species of the Arvicolinae subfamily and 3 species of the Muridae.Selection pressure analysis was performed using the PAML 4.7 software and the Datamonkey online website.Results:The COX1 protein of E.miletus comprises/consists of 514 amino acids,with leucine(Leu/L)being the most prevalent amino acid(11.5%).This hydrophilic protein contains 42 phosphorylation sites and 4 N-glycosylation sites.It possesses a transmembrane domain and lacks signal peptide distribution,thus classifying it as a non-GPI-anchored protein.The secondary structure of the COX1 protein consists ofα-helices(36.77%),random coils(33.85%),and extended chains,a composition consistent with/findings that align with its tertiary structure.Significant genetic differentiation exists among species within the Arvicolinae subfamily,a finding consistent with morphological identification results.The COX1 gene in Arvicolinae species exhibits purifying selection.Conclusion:This study analyzed the physicochemical properties of the COX1 protein in E.miletus.Phylogenetic and selection pressure analyses reveal significant genetic divergence among Arvicolinae species,and demonstrate that the COX1 gene is evolutionarily conserved within the Arvicolinae subfamily.
基金Project supported by the Natural Science Foundation of Inner Mongolia Autonomous Region of China(2021BS02007,2022MS02014)the"Science and Technology Project of Ordos"Program(2021 CGI 17-9,2021 ZDI11-14)+2 种基金the National Natural Science Foundation of China(21971129,21961022,51903125,21661023)the"Inner Mongolia Autonomous Region 2022 Leading Talent Team of Science and Technology"Program(2022LJRC0008)China Postdoctoral Science Foundation(2018M640043,2019T120038)。
文摘Neodymium-iron-boron(Nd-Fe-B)sludge is an important secondary resource of rare-earth elements(REEs).However,the state-of-the-art recycling method,i.e.,HCl-preferential dissolution faces challenges such as slow leaching kinetics,excessive chemical consumption and wastewater generation.In this work,the in situ anodic leaching of Nd-Fe-B sludge was developed to selectively recover REEs with high efficiency.The leaching rates of the REEs are 2.4-9.0 times higher using the in situ anodic leaching at the current density from 10 to 40 mA/cm^(2)than using conventional chemical leaching under the maintained pH of 3.7.Mechanism studies reveal that the anode-generated H~+plays the key role during the in situ anodic leaching process that locally increases the H^(+)concentration at the interface of sludge particles,accele rating the leaching kinetics.By achieving a total leaching efficiency of Nd-Fe-B sludge close to 100%and the Fe deposition efficiency in the range of 70.9%-74.3%,selective leaching of REEs is successfully realized and thus largely reduces chemical consumption.Additionally,a two-step recycling route involving electrolysis-selective precipitation was proposed that enables a stable REEs recovery of 92.2%with recyclable electrolyte.This study provides a novel and environmentally-friendly strategy for the efficient recovery of REEs from secondary resources.
基金supported by the National Natural Science Foundation of China(No.22271154)Natural Science Foundation of Jiangsu Province(No.BK20211179)+3 种基金Innovation Support Program of Jiangsu Province(No.BZ2023055)Fundamental Research Funds for the Central Universities(No.NS2023033)China Postdoctoral Science Foundation(No.2023M731658)Achievement Transformation Project of Qinghai Province(No.2021-SF-145).
文摘Supramolecular prodrug vesicles(H-4⊃B-2@MB)with selective antibacterial activity have been successfully constructed.Specifically,a natural antibiotic prodrug(B-2)with glutathione(GSH)-responsiveness was synthesized.The hydrophobic interaction between B-2 and a novel water-soluble cavitand with deep cavity(H-4)resulted in the formation of a host-vip complex,which further self-assembled into supramolecular vesicles.The formed vesicles could effectively encapsulate the photosensitizer methylene blue(MB),enabling co-delivery of antibiotics and photosensitizers in the presence of GSH.Moreover,upon excitation at 630 nm,the photosensitizers generate reactive oxygen species(ROS),effectively eradicating E.coli through combined chemo-photodynamic therapy.Considering that GSH is predominantly present in Gram-negative bacteria such as E.coli,this strategy exhibits substantial potential for selectively inhibiting bacteria characterized by high GSH levels to regulate bacterial colony equilibrium.
