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Trends of Superoxide Dismutase and Soluble Protein of Aquatic Plants in Lakes of Different Trophic levels in the Middle and Lower Reaches of the Yangtze River, China

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Journal of Integrative Plant Biology 2009年第4期51卷 414-422页

作者： Ai-Ping Wu Te Cao Shi-Kai Wu le-Yi ni Ping Xie Donghu Experimental Station of Lake Ecosystems The State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology the Chinese Academy of Sciences Wuhan 430072 China Ecology Department College of Bioscience and Biotechnology Hunan Agricultural University Changsha 410128 China Graduate University of the Wuhan Branch Chinese Academy of Sciences Wuhan 430072 China

A limnological study was carried out to determine the responses of superoxide dismutase （SOD） activities and soluble protein （SP） contents of 11 common aquatic plants to eutrophication stress. Field investigation in 12 lakes in the middle and lower reaches of the Yangtze River was carried out from March to September 2004. Our results indicated that non- submersed （emergent and floating-leafed） plants and submersed plants showed different responses to eutrophication stress. Both SOD activities of the non-submersed and submersed plants were negatively correlated with their SP contents （P 〈 0.000 1）. SP contents of non-submersed plants were significantly correlated with all nitrogen variables in the water （P 〈 0.05）, whereas SP contents of submersed plants were only significantly correlated with carbon variables as well as ammonium and Secchi depth （SD） in water （P 〈 0.05）. Only SOD activities of submersed plants were decreased with decline of SD in water （P 〈 0.001）. Our results indicate that the decline of SOD activities of submersed plants were mainly caused by light limitation, this showed a coincidence with the decline of macrophytes in eutrophic lakes, which might imply that the antioxidant system of the submersed plants were impaired under eutrophication stress.

关键词： eutrophication macrophytes soluble protein superoxide dismutase.

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Hydroxyl-terminated Polyethylenes Bearing Functional Side Groups:Facile Synthesis and Their Properties

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Chinese Journal of Polymer Science 2021年第8期39卷 994-1003,I0006页

作者： Wan-Bin Zhang Jie Luo Yan-Meng Wang Xiu-Zhong Zhu Ce Zhang Jing Liu Mei-le ni Guang-Hua Zhang Shaanxi Collaborative Innovation Center of Industrial Auxiliary Chemistry and Technology Shaanxi University of Science&TechnologyXi'an 710021China Shaanxi Key Laboratory of Chemical Additives for Industry College of Chemistry and Chemical EngineeringShaanxi University of Science&TechnologyXi'an 710021China School of Light Industry and Engineering Qi Lu University of Technology(Shandong Academy of Sciences)Jinan 250353China

A series of hydroxyl-terminated polyethylenes(HTPE)bearing various functional side groups(***,ester and butane groups)were synthesized by the combination of ring opening metathesis polymerization(ROMP)and visible light photocatalytic thiol-ene *** products are named as a,w-dihydroxyl-polyllpropionyloxythio)methinetrimethylene](HTPECarboxy),a,w dihydroxy-poly(methylpropionatethio)methinetrimethylene](HTPEeser)and a,wdihydroxyl-poly[(butylthio)methinetrimethylene](HTPEbutane)*** investigation of ROMP indicated that the molecular weight of resultant hydroxy-terminated polybutadiene(HTPB)can be tailored by varying the feed ratios of monomer to chain transfer agent(CTA).The exploration of the photocatalytic thiol-ene reaction between HTPB precursor and methyl-3-mercaptopropionate revealed that blue light as well as oxygen accelerated the reaction.1H-NMR and 13C-NMR results verified all the double bonds in HTPB can be modified,and the main chain of resultant polymer can be considered as ***,relationship between the structure of side groups and the thermal properties of functional PEs was *** the results suggested that the Tg was in the order of HTPEbuaneles exhibited poor thermostability as compared to ***,the promising applications for functional PEs were ***1 can be utilized as a smart material with pH-responsive properties due to its pH-dependent ionization of carboxyl side *** can be employed as a macro-initiator for building the triblock copolymer due to the presence of active hydroxyl end *** can serve as a plasticizer for PVC which can enhance the ductilityt of PVC without obviously sacrificing strength.

关键词： Polyethylene Ring-opening metathesis polymerization Thiol-ene reaction Polybutadiene Structure property relationships

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Numerical Simulation of Integrative Flow Field for Hypersonic Vehicle

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Journal of Thermal Science 2001年第2期10卷 103-108页

作者： HE Yuanyuan le Jialing ni Hongli Computational Aerodynamic Institute, China Aerodynamic Research and Development Center, Mianyang Sichuan 621000, China Computational Aerodynamic Institute China Aerodynamic Research and Development Center Mianyang China

To meet the requirements for the aerodynamic performance and thrust force demanded in hypersonic missions, the integration design of fuselage and. engine must be considered for hypersonic vehicle with a scramjet engine. The configuration of wave rider is a typical hypersonic vehicle shape, whose fore-body can compress the flow in advance and provide uniform flow for the air intake, and whose aft-body,is used as an expansion surface of nozzle. In the present paper, an engineering method is applied to define total aerodynamic characteristics of an approximate wave rider configuration. A finite volume method based on the center of grid is also employed to numerically investigate the outflow pass the same configuration. The flow field details and the aerodynamic characteristics at given conditions are obtained. The evaluation for this configuration may be used as a guide for the hypersonic vehicle experiment.

关键词： hypersonic vehicle integration finite volume method.

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Histone modification landscape and the key significance of H3K27me3 in myocardial ischaemia/reperfusion injury

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Science China(Life Sciences) 2023年第6期66卷 1264-1279页

作者： le ni Bowen Lin Yanping Zhang Lingjie Hu Jianghua Lin Fengmei Fu Meiting Shen Can Li lei Chen Jian Yang Dan Shi Yi-Han Chen Department of Cardiology Shanghai East HospitalTongji University School of MedicineShanghai200120China Key Laboratory of Arrhythmias of the Ministry of Education of China Shanghai East HospitalTongji University School of MedicineShanghai200120China Department of Vascular and Cardiology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Jinzhou Medical University Liaoning121000China Shanghai Frontiers Science Center of Nanocatalytic Medicine Shanghai200092China Department of Pathology and Pathophysiology Tongji University School of MedicineShanghai200092China Research Units of Origin and Regulation of Heart Rhythm Chinese Academy of Medical SciencesShanghai200092China

Histone modifications play crucial roles in the pathogenesis of myocardial ischaemia/reperfusion(I/R)***,a genome-wide map of histone modifications and the underlying epigenetic signatures in myocardial I/R injury have not been ***,we integrated transcriptome and epigenome of histone modifications to characterize epigenetic signatures after I/R ***-specific histone mark alterations were mainly found in H3K27me3-,H3K27ac-,and H3K4me1-marked regions 24 and 48 h after I/*** differentially modified by H3K27ac,H3K4me1 and H3K27me3 were involved in immune response,heart conduction or contraction,cytoskeleton,and angiogenesis.H3K27me3 and its methyltransferase polycomb repressor complex 2(PRC2)were upregulated in myocardial tissues after I/*** selective inhibition of EZH2(the catalytic core of PRC2),the mice manifest improved cardiac function,enhanced angiogenesis,and reduced *** investigations confirmed that EZH2 inhibition regulated H3K27me3 modification of multiple pro-angiogenic genes and ultimately enhanced angiogenic properties in vivo and in *** study delineates a landscape of histone modifications in myocardial I/R injury,and identifies H3K27me3 as a key epigenetic modifier in I/R *** inhibition of H3K27me3 and its methyltransferase might be a potential strategy for myocardial I/R injury intervention.

关键词： histone modification myocardial ischemia/reperfusion EZH2 H3K27me3 angiogenesis

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The Place of Nursing Theory in the Management of Post-Operative Infections in a Hospital Environment: Case of Cibitoke District Hospital

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Open Journal of Nursing 2024年第5期14卷 225-238页

作者： Onésime Nduwimana le Béni Bugingo Arlette Ntigura Ishimwe Abias nibaruta Faculty of Health Sciences Hope Africa University Bujumbura Burundi Faculty of Health Sciences Integrated Polytechnic University Cibitoke Burundi

Introduction: Post-operative infections, such as surgical site infections (SSIs), are a significant concern in healthcare settings. Nurses play a crucial role in the prevention and management of these infections. The use of nursing theory could contribute to the prevention of SSIs. The aim of this study was to evaluate the role of nursing theory in the management of surgical site infections (SSIs) in a hospital environment. Method: A cross-sectional study was conducted using descriptive and analytical methods to assess the role of nursing theory in the management of Post-operative infections (POI) in a hospital setting in October 2023. The study population consisted of nurses working in the Surgery, Emergency, and Maternity units at Cibitoke District Hospital. A sample size of 71 nurses working full or part time in the Surgery were invited to participate in this study. A questionnaire was used to collect the data, and SPSS version 21.0 software was used for analysis. Results: The study found that nursing theory did not have any statistically significant place in the management of POI (p-value = 0.523). However, the results showed that experience was the only significant factor influencing the management of POI (p-value = 0.004). This is explained by the analysis of the net effects of the explanatory variable where we noticed that those who had more experience were more likely to manage post-operative infections. The participants’ knowledge regarding nursing theory in the management was poor as they scored less than 30% in all the variables used to measure their knowledge. Conclusion: The study revealed that nurses’ knowledge of nursing theories and their applications in the management of SSIs was poor. Continuing professional development, curriculum review, and in-service training were highly recommended.

关键词： Nurses Postoperative Infection Surgical Site Infections Management Nursing Theory

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Fabrication of ni-Zn spinel ferrite with superior magnetic performance from electric arc furnace dust and iron scale

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JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL 2025年第1期32卷 105-114页

作者： Li, Yang Jie, Wei-zhe Chen, Chang Su, Yi Zhou, Wu Zhang, Hua ni, Hong-wei Wuhan Univ Sci & Technol State Key Lab Refractories & Met Wuhan 430081 Hubei Peoples R China Wuhan Univ Sci & Technol Key Lab Ferrous Met & Resources Utilizat Minist Educ Wuhan 430081 Hubei Peoples R China Wuhan Univ Sci & Technol Hubei Prov Key Lab Syst Sci Met Proc Wuhan 430081 Hubei Peoples R China

The ni-ZnFe2O4 (nixZn1-xFe2O4, x = 0.4-0.7) spinel was synthesized using Zn2+ extracted from electric arc furnace dust (EAFD), nickel chloride hexahydrate, and Fe3+ extracted from iron scale as raw materials. The zinc was selectively extracted from EAFD using CaO roasting followed by NH4Cl solution leaching. The ferric ion was leached from iron scale using HCl solution as acid lixiviant. The experimental results demonstrate a high level of efficiency in the extraction of zinc, with a rate of 97.5%, and the leaching rate of ferric ion is 96.89%. The composition of the leaching solution is primary zinc and iron with low calcium, which is beneficial to the preparation of spinel ferrite. The influence of ni content (x) and calcination temperature on the synthesis and magnetic properties of nixZn1-xFe2O4 compounds was investigated by X-ray diffraction, scanning electron microscopy, and vibrating sample magnetometry. The results revealed that both ni content and calcination temperature significantly affect the synthesis and magnetic properties of spinel nixZn1-xFe2O4. Under the conditions of ni content set at x = 0.6, calcination temperature of 1100 degrees C, and a duration of 2 h, a spinel nixZn1-xFe2O4 with high saturation magnetization (Ms = 65.7 A m2 kg-1) and low coercivity (Hc = 0.056 A m-1) was obtained.

关键词： Electric furnace arc dust Iron scale Spinel ferrite Magnetic performance Calcination temperature

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MOF-derived ni3Fe/ni/niFe2O4@C for enhanced hydrogen storage performance of MgH2

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Journal of Energy Chemistry 2025年第02期101卷 333-344页

作者： Yangping Chen Bolin Sun Guoqing Zhang Siyuan ni Canbing Li Juxiong Tian Yanrui Zhang Xinxi Li School of Materials and Energy Guangdong University of Technology Shen Zhen Source Sensor Technology CO. Ltd Department of Electrical Engineering Shanghai Jiao Tong University China Power Investment Xinjiang Energy & Chemical Group Hotan Co.Ltd

Magnesium hydride（MgH2） is an important material for hydrogen（H2） storage and transportation owing to its high capacity and ***,its intrinsic properties have considerably limited its industrial *** this study,the niFe-800 catalyst as metal-organic framework（MOF） derivative was first utilized to promote the intrinsic properties of *** to pure MgH2,which releases1.24 wt% H2in 60 min at 275℃,the MgH2-10 niFe-800 composite releases 5.85 wt% H2in the same *** at a lower temperature of 250℃,the MgH2-10 niFe-800 composite releases 3.57 wt% H2,surpassing the performance of pure MgH2at 275℃.Correspondingly,while pure MgH2absorbs 2.08 wt% H2in60 min at 125℃,the MgH2-10 niFe-800 composite absorbs 5.35 wt% H2in just 1 min,Remarkably,the MgH2-10 niFe-800 composite absorbs 2.27 wt% H2in 60 min at 50℃ and 4.64 wt% H2at 75℃.This indicates that MgH2-10 niFe-800 exhibits optimum performance with excellent kinetics at low ***,the capacity of the MgH2-10 niFe-800 composite remains largely stable after ***,the Mg2ni/Mg2niH4acts as a "hydrogen pump",providing effective diffusion channels that enhance the kinetic process of the composite during ***,Fe0facilitates electron transfer and creates hydrogen diffusion channels and catalytic ***,carbon（C） effectively prevents particle agglomeration and maintains the cyclic stability of the ***,the synergistic effects of Mg2ni/Mg2niH4,Fe0,and C considerably improve the kinetic properties and cycling stability of *** work offers an effective and valuable approach to improving the hydrogen storage efficiency in the commercial application of MgH2.

关键词： Catalysts Hydrogen energy MgH2 MOF derivative Solid state storage

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拐点与抉择:中国电视业发展的历史逻辑与现实进路

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现代传播（中国传媒大学学报） 2019年第9期41卷 82-88页

作者：周勇倪乐融中国人民大学新闻学院党委中国人民大学新闻与社会发展研究中心中国人民大学新闻学院

以中观视角对电视业发展进行历时性研究,选取"频道"作为电视业发展历程的贯穿性要素和观察中国电视业兴衰逻辑的重要指标。基于时段资源开发的电视频道发展,历经资源匮乏、粗放扩张和饱和分化期,直至当下面临发展困局,究其根本是频道供... 详细信息

以中观视角对电视业发展进行历时性研究,选取"频道"作为电视业发展历程的贯穿性要素和观察中国电视业兴衰逻辑的重要指标。基于时段资源开发的电视频道发展,历经资源匮乏、粗放扩张和饱和分化期,直至当下面临发展困局,究其根本是频道供应的过度饱和导致供需失衡和以时间逻辑为主导的传统电视传播模式失效。拐点时刻的中国电视业需要直面后频道时代,在行业生态、传播模式、理念认知与价值链塑造等方面寻求脱离频道模式桎梏的未来进路。

关键词：电视史电视频道时段电视传播模式后频道时代

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盐酸帕罗西汀中R-异构体的HPLC测定

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中国医药工业杂志 2005年第3期36卷 161-162页

作者：张孝君倪乐平浙江尖峰药业有限公司浙江金华321000

建立了HPLC法测定盐酸帕罗西汀中R-异构体的含量。采用Chiral-AGP手性色谱柱,考察了流动相中有机溶剂的种类和比例、磷酸盐缓冲液浓度和pH值,以及柱温、流速对分离效果的影响。结果表明,以甲醇-0.04mol/L磷酸盐缓冲液(pH5.0)(10∶90)为... 详细信息

建立了HPLC法测定盐酸帕罗西汀中R-异构体的含量。采用Chiral-AGP手性色谱柱,考察了流动相中有机溶剂的种类和比例、磷酸盐缓冲液浓度和pH值,以及柱温、流速对分离效果的影响。结果表明,以甲醇-0.04mol/L磷酸盐缓冲液(pH5.0)(10∶90)为流动相,流速0.8ml/min,检测波长293nm,盐酸帕罗西汀与其R-异构体能完全分离,两者检测限均为10ng。

关键词：帕罗西汀 R-异构体高效液相色谱测定

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Phase equilibria of Fe₃O₄-Cr₂O₃-CaO system: experimental measurements and thermodynamic calculations

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JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL 2025年第1期32卷 95-104页

作者： Zhu, Ao Shi, Chen-ying ni, Pei-yuan Deng, Teng-fei Wuhan Univ Technol State Key Lab Silicate Mat Architectures Wuhan 430070 Hubei Peoples R China Cent South Univ Coll Chem & Chem Engn Changsha 410083 Hunan Peoples R China Northeastern Univ Sch Met Key Lab Ecol Met Multimet Intergrown Ores Educ Minist Shenyang 110819 Liaoning Peoples R China

Understanding the phase equilibria of the Fe3O4-Cr2O3-CaO system is essential for the efficient recycling of stainless steel pickling sludge. The isothermal section of this system at 1473 K under oxygen partial pressure of 0.15 Pa was investigated. Key experiments on the relevant binary systems were conducted using a combination of equilibrium-quenching techniques, X-ray diffraction, high-resolution transmission electron microscope, and electron probe microanalysis. These systems were rigorously assessed using the CALPHAD (CALculation of Phase Diagram) method, incorporating the present experimental data. The liquid phase was modeled using the ionic two-sublattice model, represented as (Ca2+, Cr3+, Fe2+)(P)(O2-, Va, FeO1.5)(Q), where Va represents vacancy, and P and Q denote the number of sites on the cation and anion sublattices, respectively. To ensure electroneutrality, the values of P and Q adjust according to the composition of the mixture. From this, the isothermal section of the Fe3O4-Cr2O3-CaO system at 1473 K under the specified oxygen partial pressure was obtained based on the thermodynamic parameters of the binary systems. The present experimental data and calculation results hold significant implications for the comprehensive recycling of stainless steel pickling sludge.

关键词： Fe3O4-Cr2O3-CaO system Ionic two-sublattice model Phase equilibria CALPHAD

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