期刊文献+
共找到9篇文章
< 1 >
每页显示 20 50 100
Photocatalytic oxidation of high concentration NO over SnS_(2)/g-C_(3)N_(4): A mechanistic study
1
作者 WANG Haocun ZHANG Qixin +2 位作者 YANG Yifan BIAN Junjie LI Chunhu 《燃料化学学报(中英文)》 北大核心 2025年第3期323-335,共13页
This study aims to enhance the photocatalytic performance of 2D/2D heterojunctions for NO removal from marine vessel effluents.SnS_(2)/g-C_(3)N_(4) composites were successfully constructed via a facile solvothermal me... This study aims to enhance the photocatalytic performance of 2D/2D heterojunctions for NO removal from marine vessel effluents.SnS_(2)/g-C_(3)N_(4) composites were successfully constructed via a facile solvothermal method,demonstrating a significant improvement in photocatalytic NO removal under visible light irradiation.For high-flux simulated flue gas,the composite with 10%SnS_(2)(denoted as SNCN-10)showed exceptional NO removal efficiency,reaching up to 66.8%,along with excellent reusability over five consecutive cycles.Detailed band structure and density of states(DOS)calculations confirmed the formation of a characteristic heterojunction.Spin-trapping ESR spectroscopy identified·O_(2)^(-)−as the key reactive species driving NO oxidation.Additionally,in situ DRIFT spectroscopy revealed that SNCN-10 facilitated the conversion of NO to nitrate through intermediate species,including bridging nitrite and cis-nitrite(N_(2)O_(2)^(2-)).Kinetic studies further indicated that NO oxidation followed the Langmuir-Hinshelwood(L-H)mechanism.Based on density functional theory(DFT)calculations of free energy changes,a comprehensive reaction pathway for NO oxidation was proposed.These findings provide valuable insights for the development of efficient photocatalytic strategies for NO removal. 展开更多
关键词 polymeric g-C_(3)N_(4) charge separation PHOTOCATALYSIS NO removal DFT calculations
在线阅读 下载PDF
Recent advances of Ru-assisted semiconductor in photocatalytic N_(2) reduction to produce ammonia
2
作者 ZHAO Zehui REN Guangmin MENG Xiangchao 《燃料化学学报(中英文)》 北大核心 2025年第3期301-322,共22页
In recent years,photocatalytic N_(2) reduction for ammonia synthesis at room temperature and atmospheric pressure has gradually become a research hotspot,exhibiting extremely high development potential.However,the low... In recent years,photocatalytic N_(2) reduction for ammonia synthesis at room temperature and atmospheric pressure has gradually become a research hotspot,exhibiting extremely high development potential.However,the low photogenerated charge separation efficiency and the lack of effective active sites seriously constrain the reaction efficiencies of semiconductor photocatalysts for N_(2) reduction of ammonia synthesis.Therefore,the rational design of catalytic materials is the key to enhance the photocatalytic N_(2) reduction reaction of ammonia synthesis.Transition metal Ru as the active center not only accelerates the adsorption and activation of N_(2) molecules,but also has good selectivity for N_(2) reduction.Moreover,the interaction between the metal and the support can effectively regulate the electronic structure of the active site,accelerate the photogenerated electron transfer,and significantly enhance the photocatalytic activity.Based on this,this review systematically investigates the Ru co-semiconductors to realize efficient photocatalytic N_(2) reduction for ammonia synthesis,and introduces its basic principles.Specifically,the Ru co-semiconductor photocatalytic material systems are introduced,such as TiO2-based,g-C3N4-based,and metal oxide materials,including the design of catalysts,crystal structures,and other characteristics.In addition,the modification strategies of photocatalytic N_(2) reduction ammonia synthesis materials are also presented,including loading/doping,defect engineering,construction of heterojunctions,and crystal surface modulation.Furthermore,the progress and shortcomings of the application of Ru co-semiconductors in these processes are summarized and comprehensively discussed,and the future outlook of Ru co-semiconductors in photocatalytic N_(2) reduction ammonia synthesis applications is proposed. 展开更多
关键词 PHOTOCATALYSIS N_(2)reduction ammonia synthesis RU
在线阅读 下载PDF
Hypoxia Exercise Mediates The miR-27/PPARγ Pathway to Improve Lipid Metabolism in Obese Ratsat Target Genes and Protein Levels
3
作者 KONG Wei SHAO Jie +4 位作者 ZHAI Teng CHENG Qian HAN Fang-Zheng QU Yi ZHU Lei 《生物化学与生物物理进展》 北大核心 2025年第6期1386-1400,共15页
Objective To explore the sequential effects of hypoxic exercising on miR-27/PPARγand lipid metabolism targetgene and protein expression levels in the obesity rats’liver.Methods 13-week-old male diet-induced obesity ... Objective To explore the sequential effects of hypoxic exercising on miR-27/PPARγand lipid metabolism targetgene and protein expression levels in the obesity rats’liver.Methods 13-week-old male diet-induced obesity rats were randomlydivided into three groups(n=10):normal oxygen concentration quiet group(N),hypoxia quiet group(H),hypoxic exercise group(HE).Exercise training on the horizontal animal treadmill for 1 h/d,5 d/week for a total of 4 week,and the intensity of horizontaltreadmill training was 20 m/min(hypoxic concentration was 13.6%).Comparison of the weights of perirenal fat and epididymal fat in rats across different groups and calculation of Lee’s index based on body weight and body length of rats in each group were done.And the serum concentrations of total cholesterol(TC),triglyceride(TG),low density lipoprotein cholesterol(LDL-C),high-densitylipoprotein cholesterol(HDL-C)levels were detected.RT-PCR and Western Blot were used to detect the levels of miR-27,PPARγ,CYP7A1 and CD36.Results Hypoxic exercise decreased the expression levels of miR-27 in the obese rats’liver,however,theexpression level of PPARγwas gradually increased.The expression levels of miR-27 in HE group were significantly lower than Ngroup(P<0.05).The expression levels of PPARγmRNA in N group were significantly lower than H group(P<0.05),especially lowerthan HE group(P<0.01).The protein expression of PPARγprotein in N group was significantly lower than that other groups(P<0.01).The expression of lipid metabolism-related genes and proteins increased in the obese rats’liver.The expression of CYP7A1mRNA in N group was significantly lower than H group(P<0.05),especially lower than HE group(P<0.01).The expression ofCYP7A1 protein in the obese rats’liver in N group was extremely lower than H group and HE group(P<0.01).The proteinexpression of CD36 in N group was significantly lower than that in HE group(P<0.05).Hypoxia exercise improved the relatedphysiological and biochemical indexes of lipid metabolism disorder.The perirenal fat weight of obese rats in HE group wasextremely lower than N group and H group(P<0.01),and the perirenal fat weight in N group was significantly higher than H group(P<0.05).The epididymal fat weight in N group was significantly higher than H group(P<0.05),and extremely higher than HEgroup(P<0.01).The Lee’s index in HE group was extremely lower than N group and H group(P<0.01).The serum concentration ofTC in obese rats in HE group was extremely lower than N group and H group(P<0.01).The serum concentration of TG in HE groupwas extremely lower than N group and H group(P<0.01).The serum concentration of LDL-C in N group was extremely higher thanHE group(P<0.01).The serum concentration of HDL-C in N group was extremely lower than H group(P<0.01).Conclusion Hypoxiaand hypoxia exercise may negatively regulate the levels of PPARγby inhibiting miR-27 in the obese rats’liver,thereby affecting theexpression of downstream target genes CYP7A1 and CD36,and promoting cholesterol,fatty acid oxidation and HDL-C transport inthe liver,and ultimately the lipid levels in obese rats were improved.The effect of hypoxia exercise on improving blood lipid isbetter than simple hypoxia intervention. 展开更多
关键词 hypoxia exercise miR-27 peroxisome proliferators-activated receptor gamma obese rat
在线阅读 下载PDF
Enhancing photo-generated carriers transfer of K-C_(3)N_(4)/UiO-66-NH_(2) with Er doping for efficient photocatalytic oxidation of furfural to furoic acid
4
作者 WANG Haocun LIU Lingtao +1 位作者 BIAN Junjie LI Chunhu 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第11期1617-1628,共12页
Biomass-derived platform molecules,such as furfural,are abundant and renewable feedstock for valuable chemical production.It is critical to synthesize highly efficient photocatalysts for selective oxidation under visi... Biomass-derived platform molecules,such as furfural,are abundant and renewable feedstock for valuable chemical production.It is critical to synthesize highly efficient photocatalysts for selective oxidation under visible light.The Er@K-C_(3)N_(4)/UiO-66-NH_(2) catalyst was synthesized using a straight-forward hydrothermal technique,and exhibited exceptional efficiency in the photocatalytic oxidation of furfural to furoic acid.The catalyst was thoroughly characterized,confirming the effective adjustment of the band gap energy of Er@K-C_(3)N_(4)/UiO-66-NH_(2).Upon the optimized reaction conditions,the conversion rate of furfural reached 89.3%,with a corresponding yield of furoic acid at 79.8%.The primary reactive oxygen species was identified as·O_(2)^(-) from ESR spectra and scavenger tests.The incorporation of Er and K into the catalyst enhanced the photogenerated carriers transfer rate,hence increasing the separating efficiency of photogenerated electron-hole pairs.This study expands the potential applications of rare earth element doped g-C_(3)N_(4) in the photocatalytic selective oxidation of furfurans. 展开更多
关键词 FURFURAL furoic acid selective catalytic oxidation MOFS carbon nitride
在线阅读 下载PDF
Ultimate Strength of Hull Perforated Plate Under Extreme Cyclic Loading
5
作者 ZHENG Ji-qian FENG Liang CHEN Xu-guang 《船舶力学》 EI CSCD 北大核心 2024年第12期1925-1939,共15页
In this study, the influence of opening parameters on the ultimate strength of perforated plates subjected to extreme cyclic loading in the presence of material kinematic hardening and isotro pic hardening was analyze... In this study, the influence of opening parameters on the ultimate strength of perforated plates subjected to extreme cyclic loading in the presence of material kinematic hardening and isotro pic hardening was analyzed. It is found that the ultimate strength of the perforated plates decreases rapidly and stabilizes in the first four cycles. Plates with oblong openings have a greater ultimate strength compared to plates with rectangular openings, while the relative strengthening ratio decreases over the duration of the cycle. The location of the openings is also an important parameter that affects the strength of the structure, as the plates with openings close to the edges in the longitudinal direction have higher strengths, while in the transverse direction the strengths are higher when the openings are close to the center. Among the three opening-strengthening methods compared, the Carling stiffener method maintains a better strengthening effect under cyclic loads for many periods. 展开更多
关键词 extreme cyclic loading perforated plate ultimate strength
在线阅读 下载PDF
Hetero-interfaces coupling between FeS and Co_(3)S_(4) with enhanced electrocatalytic activity in water/seawater splitting
6
作者 ZHAO Zhan LI Jiao +1 位作者 HUANG Kelei MENG Xiangchao 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第12期1865-1876,共12页
Heterojunction catalysts composed of transition metal sulfides exhibited excellent potentials in electrocatalytic water splitting.Herein,we have designed a FeS/Co_(3)S_(4) heterojunction catalyst for hydrogen evolutio... Heterojunction catalysts composed of transition metal sulfides exhibited excellent potentials in electrocatalytic water splitting.Herein,we have designed a FeS/Co_(3)S_(4) heterojunction catalyst for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in alkaline water/seawater solution.Three-dimensional nanoarrays were grown on nickel foam,and the successful synthesis of heterojunction endowed excellent activity to the catalyst.In alkaline water/seawater solution,the low overpotentials(at current density of 10 mA/cm^(2))of HER were 120.3 and 135.6 mV and the low overpotentials of OER were 212 and 232 mV,respectively.This work provided an effective method for highly-efficiently electrocatalytic splitting of water via fabrication of heterojunction. 展开更多
关键词 hydrogen evolution reaction oxygen evolution reaction HETEROJUNCTION FeS/Co_(3)S_(4)
在线阅读 下载PDF
战略性人力资源管理职能模式研究 被引量:4
7
作者 赵领娣 巩天雷 《商业时代》 北大核心 2003年第259期40-41,共2页
随着经济全球化的深入发展和企业外部环境的快速变化,加强人力资源管理战略性职能 对企业实现既定目标的作用日益重要。本文通过对人力资源管理职能的角色分析、战略价值分析以 及活动界定,提出构建适应新经济环境的以需求为导向的企业... 随着经济全球化的深入发展和企业外部环境的快速变化,加强人力资源管理战略性职能 对企业实现既定目标的作用日益重要。本文通过对人力资源管理职能的角色分析、战略价值分析以 及活动界定,提出构建适应新经济环境的以需求为导向的企业战略性人力资源管理职能模式。 展开更多
关键词 人力资源管理 战略性职能模式 企业管理 人才市场 需求导向管理
在线阅读 下载PDF
板块三节点 被引量:6
8
作者 李三忠 吕海青 +3 位作者 侯方辉 郭晓玉 金宠 刘保华 《海洋地质动态》 2004年第11期29-39,共11页
三条板块边界常相交于一点,这一个交点就叫做板块三联接合点(简称三联点,或称三节点)。三联点相接的3个板块之间的边界可以是拉张型、挤压型或剪切型的边界,它们的组合类型比较复杂,而且稳定性不同,这对精细研究海底构造格局与演化具有... 三条板块边界常相交于一点,这一个交点就叫做板块三联接合点(简称三联点,或称三节点)。三联点相接的3个板块之间的边界可以是拉张型、挤压型或剪切型的边界,它们的组合类型比较复杂,而且稳定性不同,这对精细研究海底构造格局与演化具有重要的意义。三节点的稳定性取决于相邻板块运动的方向,一个空间位置稳定的三节点不一定在演化期间其构造活动性是稳定的或空间位置永远不变,一个不稳定的三节点必然发展到稳定的三节点。文中系统分析了海沟、洋脊以及转换断层的16种组合的几何学和相关三节点的稳定性。 展开更多
关键词 三节点 洋中脊 大陆边缘 构造
在线阅读 下载PDF
High-performance electrocatalytic nitrogen oxidation of two-dimensional MOF based on a rod-manganese motifs
9
作者 YAO Xiaoyan LI Quan +4 位作者 ZHAO Xiangyu WU Mingrui LIU Licheng WANG Wentai YAO Shuo 《燃料化学学报(中英文)》 2025年第9期1364-1372,I0015-I0026,共21页
The electrocatalytic nitrogen oxidation reaction(NOR)is a sustainable approach for converting N_(2)to NO_(3)^(-)under mild conditions.However,it still faces challenges including inefficient N_(2)absorption/activation ... The electrocatalytic nitrogen oxidation reaction(NOR)is a sustainable approach for converting N_(2)to NO_(3)^(-)under mild conditions.However,it still faces challenges including inefficient N_(2)absorption/activation and oxygen evolution competition,sluggish kinetics,low Faradaic efficiency,and limited nitrate yields.In this work,a novel two-dimensional(2D)layered MOF Mn-BCPPy(H_(2)BCPPy=3,5-di(4'-carboxyphenyl)pyridine)has been successfully synthesized.The framework is composed of a rod-manganese motifs and possesses abundant active sites including open metal sites(OMSs)and Lewis base sites(LBSs).The Mn-BCPPy is the first MOF catalyst applied in electrocatalytic NOR which NO_(3)^(-)exhibited relatively high activity with a yield of 99.75μg/(h·mg)and a Faraday efficiency(FE)of 32.09%.Furthermore,it can be used as fluorescent sensor for selectively and sensitively detect nitrofuran antibiotics(NFs).Therefore,this work explores the application of MOF materials in the field of electrocatalytic NOR,which reveals that manganese-based MOFs have great potential prospects. 展开更多
关键词 metal-organic framework electrocatalytic nitrogen oxidation nitrate fluorescence sensor
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部