In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asy...In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting.展开更多
To explore the formation mechanism of anisotropy in Ti-6Al-4V alloy fabricated by selective laser melting(SLM),the compressive mechanical properties,microhardness,microstructure,and crystallographic orientation of the...To explore the formation mechanism of anisotropy in Ti-6Al-4V alloy fabricated by selective laser melting(SLM),the compressive mechanical properties,microhardness,microstructure,and crystallographic orientation of the alloy across different planes were investigated.The anisotropy of SLM-fabricated Ti-6Al-4V alloys was analyzed,and the electron backscatter diffraction technique was used to investigate the influence of different grain types and orientations on the stress-strain distribution at various scales.Results reveal that in room-temperature compression tests at a strain rate of 10^(-3) s^(-1),both the compressive yield strength and microhardness vary along the deposition direction,indicating a certain degree of mechanical property anisotropy.The alloy exhibits a columnar microstructure;along the deposition direction,the grains appear equiaxed,and they have internal hexagonal close-packed(hcp)α/α'martensitic structure.α'phase has a preferential orientation approximately along the<0001>direction.Anisotropy arises from the high aspect ratio of columnar grains,along with the weak texture of the microstructure and low symmetry of the hcp crystal structure.展开更多
The diversion effect caused by the linked structure in a metro tunnel with cross-passage complicates the impact of longitudinal fire source location on the smoke backflow layering behavior that has not been clarified,...The diversion effect caused by the linked structure in a metro tunnel with cross-passage complicates the impact of longitudinal fire source location on the smoke backflow layering behavior that has not been clarified,despite the fact that the scenario exists in practice.A series of laboratory-scale experiments were conducted in this study to investigate the smoke back-layering length in a model tunnel with cross-passage.The heat release rate,the velocity of longitudinal air flow,and the location of the fire source were all varied.It was found that the behavior of smoke backflow for the fire source located at the upstream of bifurcation point resembles a single-hole tunnel fire.As the fire source’s position shifts downstream from the bifurcation point,the length of smoke back-layering progressively increases.A competitive interaction exists between airflow diversion and smoke diversion during smoke backflow,significantly affecting the smoke back-layering length in the main tunnel.The dimensionless smoke back-layering length model was formulated in a tunnel featuring a cross-passage,taking into account the positions of longitudinal fire sources.The dimensionless smoke back-layering length exhibits a positive correlation with the 17/18 power of total heat release rate Q and a negative correlation with the 5/2 power of longitudinal ventilation velocity V.展开更多
Selective depression of pyrite remains a major bottleneck in copper flotation,particularly when high-pyrite ores are processed and saline water is used.In such environments,conventional approaches using lime and inert...Selective depression of pyrite remains a major bottleneck in copper flotation,particularly when high-pyrite ores are processed and saline water is used.In such environments,conventional approaches using lime and inert grinding media often fail to discriminate ef-fectively between pyrite and valuable copper minerals due to strong copper activation on pyrite surfaces.This study introduced a novel approach using inorganic radicals generated from peroxymonosulfate(PMS)to selectively oxidize and depress pyrite.Flotation tests with synthetic high-pyrite ore blends showed that PMS significantly reduced pyrite recovery while maintaining or improving chalcopyrite flot-ation.Ethylenediaminetetraacetic acid(EDTA)extraction confirmed selective oxidation of pyrite,and electron paramagnetic resonance(EPR)spectroscopy identified hydroxyl(·OH)and sulfate(SO_(4)^(·-))radicals as the dominant reactive species.Iron ions from grinding me-dia and mineral surfaces were identified as key activators of PMS.A major insight was pyrite’s dual role,acting both as a radical scav-enger and an activator,which made it highly reactive and susceptible to radical-induced oxidation.This process converted surface copper-sulfur species into copper hydroxides,effectively suppressing pyrite flotation.While previous studies have applied EPR to detect radicals in simplified activator/precursor systems,this study provides the first direct mechanistic evidence of radical-driven selectivity in flotation by detecting inorganic radicals in a complex flotation slurry,thereby demonstrating their persistence under industrially relevant conditions and establishing a foundation for more effective and targeted flotation strategies.展开更多
BACKGROUND Post-stroke depression(PSD)is associated with hypothalamic-pituitary-adrenal(HPA)axis dysfunction and neurotransmitter deficits.Selective serotonin reuptake inhibitors(SSRIs)are commonly used,but their effi...BACKGROUND Post-stroke depression(PSD)is associated with hypothalamic-pituitary-adrenal(HPA)axis dysfunction and neurotransmitter deficits.Selective serotonin reuptake inhibitors(SSRIs)are commonly used,but their efficacy is limited.This study investigated whether combining SSRIs with traditional Chinese medicine(TCM)Free San could enhance their therapeutic effects.AIM To evaluate the clinical efficacy and safety of combining SSRIs with Free San in treating PSD,and to assess its impact on HPA axis function.METHODS Ninety-two patients with PSD were enrolled and randomly divided into control groups(n=46)and study groups(n=46).The control group received the SSRI paroxetine alone,whereas the study group received paroxetine combined with Free San for 4 weeks.Hamilton Depression Scale and TCM syndrome scores were assessed before and after treatment.Serum serotonin,norepinephrine,cortisol,cor-ticotropin-releasing hormone,and adrenocorticotropic hormone were measured.The treatment responses and adverse reactions were recorded.RESULTS After treatment,the Hamilton Depression Scale and TCM syndrome scores were significantly lower in the study group than in the control group(P<0.05).Serum serotonin and norepinephrine levels were significantly higher in the study group than in the control group,whereas cortisol,corticotropin-releasing hormone,and adrenocorticotropic hormone levels were significantly lower(P<0.05).The total efficacy rates were 84.78%and 65.22%in the study and control groups,respectively(P<0.05).No significant differences in adverse reactions were observed between the two groups(P>0.05).CONCLUSION Combining SSRIs with Free San can enhance therapeutic efficacy,improve depressive symptoms,and regulate HPA axis function in patients with PSD with good safety and clinical application value.展开更多
Selective laser melting(SLM),as an additive manufacturing technology,has garnered widespread attention for its capability to fabricate components with complex geometries and to tailor the microstructure and mechanical...Selective laser melting(SLM),as an additive manufacturing technology,has garnered widespread attention for its capability to fabricate components with complex geometries and to tailor the microstructure and mechanical properties under specific conditions.However,the intrinsic influence mechanism of microstructure formation under non-equilibrium solidification conditions in SLM processes has not been clearly revealed.In the present work,the influence of Al concentration and process parameters on the microstructure forming mechanism of Al_(x)CoCrFeNi HEAs prepared by SLM is investigated by molecular dynamics simulation method.The simulation results show that the difference in Al content significantly affects the microstructure formation of HEAs,including the growth rate and morphology of columnar crystals,stress distribution at grain boundaries,and defect structure.In addition,the results show that increasing the substrate temperature improves the solidification formability,reduces microstructural defects,and helps reduce residual stress in Al_(x)CoCrFeNi HEAs.By analyzing the influence of heat and solute flow in the molten pool on the growth of columnar crystals,it is found that spatial fluctuations in Al concentration during the non-equilibrium solidification process inhibit the high cooling rates induced by steep temperature gradients.These findings promote the understanding of the forming mechanism of microstructure in HEAs prepared by SLM and provide theoretical guidance for designing high-performance SLM-fabricated HEAs.展开更多
Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via lo...Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via low-temperature coprecipitation,exhibiting excellent performance for the selective hydrogenation of 5-hydroxymethylfurfural(HMF).A linear correlation is first observed between solvent polarity(E_(T)(30))and product selectivity within both polar aprotic and protic solvent classes,suggesting that solvent properties play a vital role in directing reaction pathways.Among these,1,4-dioxane(aprotic)favors the formation of 2,5-bis(hydroxymethyl)furan(BHMF)with 97.5%selectivity,while isopropanol(iPrOH,protic)promotes 2,5-dimethylfuran production with up to 99.5%selectivity.Mechanistic investigations further reveal that beyond polarity,proton-donating ability is critical in facilitating hydrodeoxygenation.iPrOH enables a hydrogen shuttle mechanism where protons assist in hydroxyl group removal,lowering the activation barrier.In contrast,1,4-dioxane,lacking hydrogen bond donors,stabilizes BHMF and hinders further conversion.Density functional theory calculations confirm a lower activation energy in iPrOH(0.60 eV)compared to 1,4-dioxane(1.07 eV).This work offers mechanistic insights and a practical strategy for solvent-mediated control of product selectivity in biomass hydrogenation,highlighting the decisive role of solvent-catalyst-substrate interactions.展开更多
The recovery of gold from waste electronic and electric equipment(WEEE) has gained great attention with the increased number of WEEE,because it can largely alleviate the pressure on the environment and resources.Coval...The recovery of gold from waste electronic and electric equipment(WEEE) has gained great attention with the increased number of WEEE,because it can largely alleviate the pressure on the environment and resources.Covalent organic frameworks(COFs) are ideal adsorbents for gold recovery owing to their large surface area,good stability,easily functionalized ability,periodic structures,and definitive nanopores.Herein,a cyano-functionalized COF(COF-CN) with high crystallinity was large-scale prepared under mild conditions for the recovery of gold.The introduction of cyano groups enable COF-CN to exhibit excellent gold recovery performance,which possesses fast adsorption kinetics,high cycling stability,and adsorption capacity up to 663.67 mg/g.Excitingly,COF-CN showed extremely high selectivity for gold ions,even in the presence of various competing cations and anions.The COF-CN maintained excellent selectivity and removal efficiency in gold recovery experiments from WEEE.The facile synthesis of COF-CN and its outstanding selectivity in actual samples make it an attractive opportunity for practical gold recovery.展开更多
Metal hydrides with high hydrogen density provide promising hydrogen storage paths for hydrogen transportation.However,the requirement of highly pure H_(2)for re-hydrogenation limits its wide application.Here,amorphou...Metal hydrides with high hydrogen density provide promising hydrogen storage paths for hydrogen transportation.However,the requirement of highly pure H_(2)for re-hydrogenation limits its wide application.Here,amorphous Al_(2)O_(3)shells(10 nm)were deposited on the surface of highly active hydrogen storage material particles(MgH_(2)-ZrTi)by atomic layer deposition to obtain MgH_(2)-ZrTi@Al_(2)O_(3),which have been demonstrated to be air stable with selective adsorption of H_(2)under a hydrogen atmosphere with different impurities(CH_(4),O_(2),N_(2),and CO_(2)).About 4.79 wt% H_(2)was adsorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)at 75℃under 10%CH_(4)+90%H_(2)atmosphere within 3 h with no kinetic or density decay after 5 cycles(~100%capacity retention).Furthermore,about 4 wt%of H_(2)was absorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)under 0.1%O_(2)+0.4%N_(2)+99.5%H_(2)and 0.1%CO_(2)+0.4%N_(2)+99.5%H_(2)atmospheres at 100℃within 0.5 h,respectively,demonstrating the selective hydrogen absorption of MgH_(2)-ZrTi@10nmAl_(2)O_(3)in both oxygen-containing and carbon dioxide-containing atmospheres hydrogen atmosphere.The absorption and desorption curves of MgH_(2)-ZrTi@10nmAl_(2)O_(3)with and without absorption in pure hydrogen and then in 21%O_(2)+79%N_(2)for 1 h were found to overlap,further confirming the successful shielding effect of Al_(2)O_(3)shells against O_(2)and N_(2).The MgH_(2)-ZrTi@10nmAl_(2)O_(3)has been demonstrated to be air stable and have excellent selective hydrogen absorption performance under the atmosphere with CH_(4),O_(2),N_(2),and CO_(2).展开更多
Cu electrocatalysts have been demonstrated to have unique ability to reduce CO_(2)to various high value-added C_(2) products like ethylene and alcohols.However,realizing high selectivity of C_(2) products are still a ...Cu electrocatalysts have been demonstrated to have unique ability to reduce CO_(2)to various high value-added C_(2) products like ethylene and alcohols.However,realizing high selectivity of C_(2) products are still a main challenge due to complex CO_(2)electroreduction pathways and small opportunity of Csingle bondC coupling reactions.Here,we found the origin of enhanced CO_(2)electroreduction reaction activity and product selectivity towards C_(2) products and Csingle bondC coupling mechanism at halogen atoms-adsorbed Cu/H_(2)O interfaces,the corresponding CO_(2)electroreduction evolution mechanisms at the halogen atoms-modified Cu/H_(2)O interfaces are systematically studied via theoretical modeling and calculations.The calculated results indicate that halide anions modifications are beneficial to CO dimerization into OCCO dimer,especially Cl^(-)-adsorbed Cu(111)/H_(2)O interface has the optimum activity and selectivity towards OCCO dimer,subsequent Cl-adsorbed Cu(111)/H_(2)O interface can selectively reduce CO_(2)into C_(2)H_(4) product.The function relationship between adsorption free energy of Cl atom and electrode potential explain why the adsorption of Cl^(-)can enhance selectivity of C_(2)H_(4) product.The determinations of onset potentials indicate that electroreduction pathways of CO_(2)towards C_(2)H_(4) product are facile to take place and further explain the origin of the significantly enhanced CO production activity and C_(2)H_(4) product selectivity.This work on selective realization of CO_(2)electroreduction towards C_(2)H_(4) product via Cl^(-)-modified Cu(111)/H_(2)O interface provide a theoretical guideline for how to selectively realize other high value-added C_(2) products.展开更多
The growing consumption of light olefins has stimulated intensive researches on methanol to olefin(MTO)process which possesses great advantages for coal conversion to value‐added chemicals in an environmentally benig...The growing consumption of light olefins has stimulated intensive researches on methanol to olefin(MTO)process which possesses great advantages for coal conversion to value‐added chemicals in an environmentally benign way.The catalysts commonly used for MTO process faces several challenges such as poor selectivity control,low hydrothermal stability and short lifetime.In the present study,we prepared a series of mordenite zeolites with variable Al contents(Si/Al molar ratios of 51−436)by a sequential dealumination treatment of air‐calcination and acid leaching.The textural properties,acidity and Al location before and after the dealumination treatment have been systematically studied and their effect on MTO especially the methanol to propylene(MTP)performance was thoroughly investigated.The mordenite zeolites with the Si/Al ratios over 150 selectively catalyzed methanol conversion in the MTP pathway,providing a high propylene selectivity of 63%and propylene/ethylene ratio of>10.Compared to the low‐silica MOR catalysts,highly dealuminated MOR showed much higher stability and longer lifetime,which can be further enhanced via harsh hydrothermal pretreatment.Furthermore,the lifetime was highly related to the crystal size along c‐axis.The excellent performance of highly dealuminated MOR is likely ascribed to the mesopores formed upon dealumination and the scarce Al sites located in the T sites shared by the 8‐member ring(MR)side pockets and 12‐MR pore channels.展开更多
In this paper, we obtain optimum allocation of replaceable and repairable components in a system design. When repair and replace time are considered as random in the constraints. We convert probabilistic constraint in...In this paper, we obtain optimum allocation of replaceable and repairable components in a system design. When repair and replace time are considered as random in the constraints. We convert probabilistic constraint into an equivalent deterministic constraint by using chance constrained programming. We have used the selective maintenance policy to determine how many components to be replaced & repaired within the limited maintenance time interval and cost. A Numerical example is presented to illustrate the computational procedure and problem is solved by using LINGO Software.展开更多
This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 3:Mouse.This standard was released by the China Associ...This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 3:Mouse.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU.展开更多
This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 2:Rat.This standard was released by the China Associat...This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 2:Rat.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-Zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU.展开更多
This research aims to study the bio-adsorption process of two dyes,Cibacron Green H3G(CG-H3G)and Terasil Red(TR),in a single system and to bring them closer to the industrial textile discharge by a binary mixture of t...This research aims to study the bio-adsorption process of two dyes,Cibacron Green H3G(CG-H3G)and Terasil Red(TR),in a single system and to bring them closer to the industrial textile discharge by a binary mixture of two dyes(TR+CG-H3G).The Cockle Shell(CS)was used as a natural bio-adsorbent.The characterizations of CS were investigated by Fourier transform infrared(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDX)and Brunauer–Emmett–Teller(BET).The adsorption potential of Cockle Shells was tested in two cases(single and binary system)and determined by:contact time(0–60 min),bio-adsorption dose(3–15 g/L),initial concentration(10–300 mg/L),temperature(22–61°C)and pH solution(2–12).The study of bio-adsorption(equilibrium and kinetics)was conducted at 22°C.The kinetic studies demon-strated that a pseudo-second-order adsorption mechanism had a good correlation coefficient(R2≥0.999).The Langmuir isotherm modeling provided a well-defined description of TR and CG-H3G bio-adsorption on cockle shells,exhibiting maximum capacities of 29.41 and 3.69 mg/g respectively at 22°C.The thermodynamic study shows that the reaction between the TR,CG-H3G dyes molecules and the bio-adsorbent is exothermic,spontaneous in the range of 22–31°C with the aleatory character decrease at the solid-liquid interface.The study of selectivity in single and binary systems has been performed under optimal operating conditions using the industrial textile rejection pH(pH=6.04).CG-H3G dye is found to have a higher selectivity than TR in single(0–60 min)and binary systems with a range of 6–45 min,as shown by the selectivity measurement.It was discovered that CS has the capability to remove both CG-H3G and TR dyes in both simple and binary systems,making it a superior bio-adsorbent.展开更多
Despite advances in surgery,chemotherapy,and radiotherapy,the treatment of colorectal cancer(CRC)requires more personalized approaches based on tumor biology and molecular profiling.While some relevant mutations have ...Despite advances in surgery,chemotherapy,and radiotherapy,the treatment of colorectal cancer(CRC)requires more personalized approaches based on tumor biology and molecular profiling.While some relevant mutations have been associated with differential response to immunotherapy,such as RAS and BRAF mutations limiting response to anti-epithelial growth factor receptor drugs or microsatellite instability predisposing susceptibility to immune checkpoint inhibitors,the role of inflammation in dictating tumor progression and treatment response is still under investigation.Several inflammatory biomarkers have been identified to guide patient prognosis.These include the neutrophil-lymphocyte ratio,Glasgow prognostic score(GPS)and its modified version,lymphocyte-Creactive protein ratio,and platelet-lymphocyte ratio.However,these markers are not yet included in the standard clinical management of patients with CRC,and further research is needed to evaluate their efficacy in different patient populations.A recent study by Wang et al,published in the World Journal of Gastroenterology,sheds light on the prognostic significance of pan-immune-inflammation value(PIV)in CRC,particularly concerning primary tumor location.Specifically,the authors found that a high PIV was strongly correlated with worse disease-free survival in patients with left-sided colon cancer,whereas no such association was observed in patients with right-sided colon cancer.Integrating tumor location into the prognostic assessment of CRC may improve our ability to more accurately identify high-risk patients and develop personalized treatment plans that are more likely to improve patient outcomes.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
Emerging new races of wheat stem rust(Puccinia graminis f.sp.tritici)are threatening global wheat(Triticum aestivum L.)production.Host resistance is the most effective and environmentally friendly method of controllin...Emerging new races of wheat stem rust(Puccinia graminis f.sp.tritici)are threatening global wheat(Triticum aestivum L.)production.Host resistance is the most effective and environmentally friendly method of controlling stem rust.The stem rust resistance gene Sr59 was previously identified within a T2DS 2RL wheat-rye whole arm translocation,providing broad-spectrum resistance to various stem rust races.Seedling evaluation,molecular marker analysis,and cytogenetic studies identified wheat-rye introgression line#284 containing a new translocation chromosome T2BL 2BS-2RL.This line has demonstrated broad-spectrum resistance to stem rust at the seedling stage.Seedling evaluation and cytogenetic analysis of three backcross populations between the line#284 and the adapted cultivars SLU-Elite,Navruz,and Linkert confirmed that Sr59 is located within the short distal 2RL translocation.This study aimed physical mapping of Sr59 in the 2RL introgression segment and develop a robust molecular marker for marker-assisted selection.Using genotyping-by-sequencing(GBS),GBS-derived SNPs were aligned with full-length annotated rye nucleotide-binding leucine-rich repeat(NLR)genes in the parental lines CS ph1b,SLU238,SLU-Elite,Navruz,and Linkert,as well as in 33 BC4F5progeny.Four NLR genes were identified on the 2R chromosome,with Chr2R_NLR_60 being tightly linked to the Sr59resistance gene.In-silico functional enrichment analysis of the translocated 2RL region(25,681,915 bp)identified 223 genes,with seven candidate genes associated with plant disease resistance and three linked to agronomic performance,contributing to oxidative stress response,protein kinase activity,and cellular homeostasis.These findings facilitate a better understanding of the genetic basis of stem rust resistance provided by Sr59.展开更多
基金Supported by the National Natural Science Foundation of China(12261018)Universities Key Laboratory of Mathematical Modeling and Data Mining in Guizhou Province(2023013)。
文摘In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting.
基金National Natural Science Foundation of China(51504138,51674118,52271177)Hunan Provincial Natural Science Foundation of China(2023JJ50181)Supported by State Key Laboratory of Materials Processing and Die&Mould Technology,Huazhong University of Science and Technology(P2024-022)。
文摘To explore the formation mechanism of anisotropy in Ti-6Al-4V alloy fabricated by selective laser melting(SLM),the compressive mechanical properties,microhardness,microstructure,and crystallographic orientation of the alloy across different planes were investigated.The anisotropy of SLM-fabricated Ti-6Al-4V alloys was analyzed,and the electron backscatter diffraction technique was used to investigate the influence of different grain types and orientations on the stress-strain distribution at various scales.Results reveal that in room-temperature compression tests at a strain rate of 10^(-3) s^(-1),both the compressive yield strength and microhardness vary along the deposition direction,indicating a certain degree of mechanical property anisotropy.The alloy exhibits a columnar microstructure;along the deposition direction,the grains appear equiaxed,and they have internal hexagonal close-packed(hcp)α/α'martensitic structure.α'phase has a preferential orientation approximately along the<0001>direction.Anisotropy arises from the high aspect ratio of columnar grains,along with the weak texture of the microstructure and low symmetry of the hcp crystal structure.
基金funded by the National Natural Science Foundation of China(NSFC)under Grant No.52278415the National Key Research and Development Program of China under Grant No.2022YFC3801104+2 种基金Hebei Provincial Department of Education Project under Grant No.QN2025304the Innovation Fund Project of Hebei University of Engineering under Grant No.SJ2401002066the Sichuan Science and Technology Program under Grant No.2023YFS0407。
文摘The diversion effect caused by the linked structure in a metro tunnel with cross-passage complicates the impact of longitudinal fire source location on the smoke backflow layering behavior that has not been clarified,despite the fact that the scenario exists in practice.A series of laboratory-scale experiments were conducted in this study to investigate the smoke back-layering length in a model tunnel with cross-passage.The heat release rate,the velocity of longitudinal air flow,and the location of the fire source were all varied.It was found that the behavior of smoke backflow for the fire source located at the upstream of bifurcation point resembles a single-hole tunnel fire.As the fire source’s position shifts downstream from the bifurcation point,the length of smoke back-layering progressively increases.A competitive interaction exists between airflow diversion and smoke diversion during smoke backflow,significantly affecting the smoke back-layering length in the main tunnel.The dimensionless smoke back-layering length model was formulated in a tunnel featuring a cross-passage,taking into account the positions of longitudinal fire sources.The dimensionless smoke back-layering length exhibits a positive correlation with the 17/18 power of total heat release rate Q and a negative correlation with the 5/2 power of longitudinal ventilation velocity V.
基金support from the Australian Research Council(ARC)Linkage Project(No.LP230100166).
文摘Selective depression of pyrite remains a major bottleneck in copper flotation,particularly when high-pyrite ores are processed and saline water is used.In such environments,conventional approaches using lime and inert grinding media often fail to discriminate ef-fectively between pyrite and valuable copper minerals due to strong copper activation on pyrite surfaces.This study introduced a novel approach using inorganic radicals generated from peroxymonosulfate(PMS)to selectively oxidize and depress pyrite.Flotation tests with synthetic high-pyrite ore blends showed that PMS significantly reduced pyrite recovery while maintaining or improving chalcopyrite flot-ation.Ethylenediaminetetraacetic acid(EDTA)extraction confirmed selective oxidation of pyrite,and electron paramagnetic resonance(EPR)spectroscopy identified hydroxyl(·OH)and sulfate(SO_(4)^(·-))radicals as the dominant reactive species.Iron ions from grinding me-dia and mineral surfaces were identified as key activators of PMS.A major insight was pyrite’s dual role,acting both as a radical scav-enger and an activator,which made it highly reactive and susceptible to radical-induced oxidation.This process converted surface copper-sulfur species into copper hydroxides,effectively suppressing pyrite flotation.While previous studies have applied EPR to detect radicals in simplified activator/precursor systems,this study provides the first direct mechanistic evidence of radical-driven selectivity in flotation by detecting inorganic radicals in a complex flotation slurry,thereby demonstrating their persistence under industrially relevant conditions and establishing a foundation for more effective and targeted flotation strategies.
基金Supported by Open Project of Jiangsu Province Key Laboratory of Integrated Traditional Chinese and Western Medicine for the Prevention and Treatment of Geriatric Diseases,No.202232.
文摘BACKGROUND Post-stroke depression(PSD)is associated with hypothalamic-pituitary-adrenal(HPA)axis dysfunction and neurotransmitter deficits.Selective serotonin reuptake inhibitors(SSRIs)are commonly used,but their efficacy is limited.This study investigated whether combining SSRIs with traditional Chinese medicine(TCM)Free San could enhance their therapeutic effects.AIM To evaluate the clinical efficacy and safety of combining SSRIs with Free San in treating PSD,and to assess its impact on HPA axis function.METHODS Ninety-two patients with PSD were enrolled and randomly divided into control groups(n=46)and study groups(n=46).The control group received the SSRI paroxetine alone,whereas the study group received paroxetine combined with Free San for 4 weeks.Hamilton Depression Scale and TCM syndrome scores were assessed before and after treatment.Serum serotonin,norepinephrine,cortisol,cor-ticotropin-releasing hormone,and adrenocorticotropic hormone were measured.The treatment responses and adverse reactions were recorded.RESULTS After treatment,the Hamilton Depression Scale and TCM syndrome scores were significantly lower in the study group than in the control group(P<0.05).Serum serotonin and norepinephrine levels were significantly higher in the study group than in the control group,whereas cortisol,corticotropin-releasing hormone,and adrenocorticotropic hormone levels were significantly lower(P<0.05).The total efficacy rates were 84.78%and 65.22%in the study and control groups,respectively(P<0.05).No significant differences in adverse reactions were observed between the two groups(P>0.05).CONCLUSION Combining SSRIs with Free San can enhance therapeutic efficacy,improve depressive symptoms,and regulate HPA axis function in patients with PSD with good safety and clinical application value.
基金supported by the National Natural Science Foundation of China(Grant No.12102133).
文摘Selective laser melting(SLM),as an additive manufacturing technology,has garnered widespread attention for its capability to fabricate components with complex geometries and to tailor the microstructure and mechanical properties under specific conditions.However,the intrinsic influence mechanism of microstructure formation under non-equilibrium solidification conditions in SLM processes has not been clearly revealed.In the present work,the influence of Al concentration and process parameters on the microstructure forming mechanism of Al_(x)CoCrFeNi HEAs prepared by SLM is investigated by molecular dynamics simulation method.The simulation results show that the difference in Al content significantly affects the microstructure formation of HEAs,including the growth rate and morphology of columnar crystals,stress distribution at grain boundaries,and defect structure.In addition,the results show that increasing the substrate temperature improves the solidification formability,reduces microstructural defects,and helps reduce residual stress in Al_(x)CoCrFeNi HEAs.By analyzing the influence of heat and solute flow in the molten pool on the growth of columnar crystals,it is found that spatial fluctuations in Al concentration during the non-equilibrium solidification process inhibit the high cooling rates induced by steep temperature gradients.These findings promote the understanding of the forming mechanism of microstructure in HEAs prepared by SLM and provide theoretical guidance for designing high-performance SLM-fabricated HEAs.
基金the National Nature Science Foundation of China for Excellent Young Scientists Fund(32222058)Fundamental Research Foundation of CAF(CAFYBB2022QB001).
文摘Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via low-temperature coprecipitation,exhibiting excellent performance for the selective hydrogenation of 5-hydroxymethylfurfural(HMF).A linear correlation is first observed between solvent polarity(E_(T)(30))and product selectivity within both polar aprotic and protic solvent classes,suggesting that solvent properties play a vital role in directing reaction pathways.Among these,1,4-dioxane(aprotic)favors the formation of 2,5-bis(hydroxymethyl)furan(BHMF)with 97.5%selectivity,while isopropanol(iPrOH,protic)promotes 2,5-dimethylfuran production with up to 99.5%selectivity.Mechanistic investigations further reveal that beyond polarity,proton-donating ability is critical in facilitating hydrodeoxygenation.iPrOH enables a hydrogen shuttle mechanism where protons assist in hydroxyl group removal,lowering the activation barrier.In contrast,1,4-dioxane,lacking hydrogen bond donors,stabilizes BHMF and hinders further conversion.Density functional theory calculations confirm a lower activation energy in iPrOH(0.60 eV)compared to 1,4-dioxane(1.07 eV).This work offers mechanistic insights and a practical strategy for solvent-mediated control of product selectivity in biomass hydrogenation,highlighting the decisive role of solvent-catalyst-substrate interactions.
基金financially supported by the National Natural Science Foundation of China (No.51972302)。
文摘The recovery of gold from waste electronic and electric equipment(WEEE) has gained great attention with the increased number of WEEE,because it can largely alleviate the pressure on the environment and resources.Covalent organic frameworks(COFs) are ideal adsorbents for gold recovery owing to their large surface area,good stability,easily functionalized ability,periodic structures,and definitive nanopores.Herein,a cyano-functionalized COF(COF-CN) with high crystallinity was large-scale prepared under mild conditions for the recovery of gold.The introduction of cyano groups enable COF-CN to exhibit excellent gold recovery performance,which possesses fast adsorption kinetics,high cycling stability,and adsorption capacity up to 663.67 mg/g.Excitingly,COF-CN showed extremely high selectivity for gold ions,even in the presence of various competing cations and anions.The COF-CN maintained excellent selectivity and removal efficiency in gold recovery experiments from WEEE.The facile synthesis of COF-CN and its outstanding selectivity in actual samples make it an attractive opportunity for practical gold recovery.
基金supported by the National Natural Science Foundation of China(22175136)the State Key Laboratory of Electrical Insulation and Power Equipment(EIPE23127)the Fundamental Research Funds for the Central Universities(xtr052024009).
文摘Metal hydrides with high hydrogen density provide promising hydrogen storage paths for hydrogen transportation.However,the requirement of highly pure H_(2)for re-hydrogenation limits its wide application.Here,amorphous Al_(2)O_(3)shells(10 nm)were deposited on the surface of highly active hydrogen storage material particles(MgH_(2)-ZrTi)by atomic layer deposition to obtain MgH_(2)-ZrTi@Al_(2)O_(3),which have been demonstrated to be air stable with selective adsorption of H_(2)under a hydrogen atmosphere with different impurities(CH_(4),O_(2),N_(2),and CO_(2)).About 4.79 wt% H_(2)was adsorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)at 75℃under 10%CH_(4)+90%H_(2)atmosphere within 3 h with no kinetic or density decay after 5 cycles(~100%capacity retention).Furthermore,about 4 wt%of H_(2)was absorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)under 0.1%O_(2)+0.4%N_(2)+99.5%H_(2)and 0.1%CO_(2)+0.4%N_(2)+99.5%H_(2)atmospheres at 100℃within 0.5 h,respectively,demonstrating the selective hydrogen absorption of MgH_(2)-ZrTi@10nmAl_(2)O_(3)in both oxygen-containing and carbon dioxide-containing atmospheres hydrogen atmosphere.The absorption and desorption curves of MgH_(2)-ZrTi@10nmAl_(2)O_(3)with and without absorption in pure hydrogen and then in 21%O_(2)+79%N_(2)for 1 h were found to overlap,further confirming the successful shielding effect of Al_(2)O_(3)shells against O_(2)and N_(2).The MgH_(2)-ZrTi@10nmAl_(2)O_(3)has been demonstrated to be air stable and have excellent selective hydrogen absorption performance under the atmosphere with CH_(4),O_(2),N_(2),and CO_(2).
基金supported by the Natural Science Foundation of Hunan Province(No.2025JJ50059)Key Program of Hunan University of Arts and Science(No.23ZZ03)Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province and National Natural Science Foundation of China(No.21303048).
文摘Cu electrocatalysts have been demonstrated to have unique ability to reduce CO_(2)to various high value-added C_(2) products like ethylene and alcohols.However,realizing high selectivity of C_(2) products are still a main challenge due to complex CO_(2)electroreduction pathways and small opportunity of Csingle bondC coupling reactions.Here,we found the origin of enhanced CO_(2)electroreduction reaction activity and product selectivity towards C_(2) products and Csingle bondC coupling mechanism at halogen atoms-adsorbed Cu/H_(2)O interfaces,the corresponding CO_(2)electroreduction evolution mechanisms at the halogen atoms-modified Cu/H_(2)O interfaces are systematically studied via theoretical modeling and calculations.The calculated results indicate that halide anions modifications are beneficial to CO dimerization into OCCO dimer,especially Cl^(-)-adsorbed Cu(111)/H_(2)O interface has the optimum activity and selectivity towards OCCO dimer,subsequent Cl-adsorbed Cu(111)/H_(2)O interface can selectively reduce CO_(2)into C_(2)H_(4) product.The function relationship between adsorption free energy of Cl atom and electrode potential explain why the adsorption of Cl^(-)can enhance selectivity of C_(2)H_(4) product.The determinations of onset potentials indicate that electroreduction pathways of CO_(2)towards C_(2)H_(4) product are facile to take place and further explain the origin of the significantly enhanced CO production activity and C_(2)H_(4) product selectivity.This work on selective realization of CO_(2)electroreduction towards C_(2)H_(4) product via Cl^(-)-modified Cu(111)/H_(2)O interface provide a theoretical guideline for how to selectively realize other high value-added C_(2) products.
文摘The growing consumption of light olefins has stimulated intensive researches on methanol to olefin(MTO)process which possesses great advantages for coal conversion to value‐added chemicals in an environmentally benign way.The catalysts commonly used for MTO process faces several challenges such as poor selectivity control,low hydrothermal stability and short lifetime.In the present study,we prepared a series of mordenite zeolites with variable Al contents(Si/Al molar ratios of 51−436)by a sequential dealumination treatment of air‐calcination and acid leaching.The textural properties,acidity and Al location before and after the dealumination treatment have been systematically studied and their effect on MTO especially the methanol to propylene(MTP)performance was thoroughly investigated.The mordenite zeolites with the Si/Al ratios over 150 selectively catalyzed methanol conversion in the MTP pathway,providing a high propylene selectivity of 63%and propylene/ethylene ratio of>10.Compared to the low‐silica MOR catalysts,highly dealuminated MOR showed much higher stability and longer lifetime,which can be further enhanced via harsh hydrothermal pretreatment.Furthermore,the lifetime was highly related to the crystal size along c‐axis.The excellent performance of highly dealuminated MOR is likely ascribed to the mesopores formed upon dealumination and the scarce Al sites located in the T sites shared by the 8‐member ring(MR)side pockets and 12‐MR pore channels.
文摘In this paper, we obtain optimum allocation of replaceable and repairable components in a system design. When repair and replace time are considered as random in the constraints. We convert probabilistic constraint into an equivalent deterministic constraint by using chance constrained programming. We have used the selective maintenance policy to determine how many components to be replaced & repaired within the limited maintenance time interval and cost. A Numerical example is presented to illustrate the computational procedure and problem is solved by using LINGO Software.
文摘This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 3:Mouse.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU.
文摘This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 2:Rat.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-Zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU.
基金supported by the University Salah Boubnider-Constantine 3 (Algeria).
文摘This research aims to study the bio-adsorption process of two dyes,Cibacron Green H3G(CG-H3G)and Terasil Red(TR),in a single system and to bring them closer to the industrial textile discharge by a binary mixture of two dyes(TR+CG-H3G).The Cockle Shell(CS)was used as a natural bio-adsorbent.The characterizations of CS were investigated by Fourier transform infrared(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDX)and Brunauer–Emmett–Teller(BET).The adsorption potential of Cockle Shells was tested in two cases(single and binary system)and determined by:contact time(0–60 min),bio-adsorption dose(3–15 g/L),initial concentration(10–300 mg/L),temperature(22–61°C)and pH solution(2–12).The study of bio-adsorption(equilibrium and kinetics)was conducted at 22°C.The kinetic studies demon-strated that a pseudo-second-order adsorption mechanism had a good correlation coefficient(R2≥0.999).The Langmuir isotherm modeling provided a well-defined description of TR and CG-H3G bio-adsorption on cockle shells,exhibiting maximum capacities of 29.41 and 3.69 mg/g respectively at 22°C.The thermodynamic study shows that the reaction between the TR,CG-H3G dyes molecules and the bio-adsorbent is exothermic,spontaneous in the range of 22–31°C with the aleatory character decrease at the solid-liquid interface.The study of selectivity in single and binary systems has been performed under optimal operating conditions using the industrial textile rejection pH(pH=6.04).CG-H3G dye is found to have a higher selectivity than TR in single(0–60 min)and binary systems with a range of 6–45 min,as shown by the selectivity measurement.It was discovered that CS has the capability to remove both CG-H3G and TR dyes in both simple and binary systems,making it a superior bio-adsorbent.
文摘Despite advances in surgery,chemotherapy,and radiotherapy,the treatment of colorectal cancer(CRC)requires more personalized approaches based on tumor biology and molecular profiling.While some relevant mutations have been associated with differential response to immunotherapy,such as RAS and BRAF mutations limiting response to anti-epithelial growth factor receptor drugs or microsatellite instability predisposing susceptibility to immune checkpoint inhibitors,the role of inflammation in dictating tumor progression and treatment response is still under investigation.Several inflammatory biomarkers have been identified to guide patient prognosis.These include the neutrophil-lymphocyte ratio,Glasgow prognostic score(GPS)and its modified version,lymphocyte-Creactive protein ratio,and platelet-lymphocyte ratio.However,these markers are not yet included in the standard clinical management of patients with CRC,and further research is needed to evaluate their efficacy in different patient populations.A recent study by Wang et al,published in the World Journal of Gastroenterology,sheds light on the prognostic significance of pan-immune-inflammation value(PIV)in CRC,particularly concerning primary tumor location.Specifically,the authors found that a high PIV was strongly correlated with worse disease-free survival in patients with left-sided colon cancer,whereas no such association was observed in patients with right-sided colon cancer.Integrating tumor location into the prognostic assessment of CRC may improve our ability to more accurately identify high-risk patients and develop personalized treatment plans that are more likely to improve patient outcomes.
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the financial support from FORMAS(2018-01029)the Swedish Institute(01132-2022)for supporting Ivan Motsnyi’s visit and research at Swedish University of Agricultural Sciences。
文摘Emerging new races of wheat stem rust(Puccinia graminis f.sp.tritici)are threatening global wheat(Triticum aestivum L.)production.Host resistance is the most effective and environmentally friendly method of controlling stem rust.The stem rust resistance gene Sr59 was previously identified within a T2DS 2RL wheat-rye whole arm translocation,providing broad-spectrum resistance to various stem rust races.Seedling evaluation,molecular marker analysis,and cytogenetic studies identified wheat-rye introgression line#284 containing a new translocation chromosome T2BL 2BS-2RL.This line has demonstrated broad-spectrum resistance to stem rust at the seedling stage.Seedling evaluation and cytogenetic analysis of three backcross populations between the line#284 and the adapted cultivars SLU-Elite,Navruz,and Linkert confirmed that Sr59 is located within the short distal 2RL translocation.This study aimed physical mapping of Sr59 in the 2RL introgression segment and develop a robust molecular marker for marker-assisted selection.Using genotyping-by-sequencing(GBS),GBS-derived SNPs were aligned with full-length annotated rye nucleotide-binding leucine-rich repeat(NLR)genes in the parental lines CS ph1b,SLU238,SLU-Elite,Navruz,and Linkert,as well as in 33 BC4F5progeny.Four NLR genes were identified on the 2R chromosome,with Chr2R_NLR_60 being tightly linked to the Sr59resistance gene.In-silico functional enrichment analysis of the translocated 2RL region(25,681,915 bp)identified 223 genes,with seven candidate genes associated with plant disease resistance and three linked to agronomic performance,contributing to oxidative stress response,protein kinase activity,and cellular homeostasis.These findings facilitate a better understanding of the genetic basis of stem rust resistance provided by Sr59.
