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园艺植物研究法课程教学改革探索

安徽农业科学 2022年第3期50卷 271-273页

作者：刘莉郑文娟张倩男栾晓龙贾兵安徽农业大学园艺学院安徽合肥230036

园艺植物研究法是我国高校为园艺专业开设的一门高级专业课,是为了培养学生独自开展科研的综合素养与能力。总结了该课程教学中存在的问题,主要包括课程教学与实验相分离、学生学习效果差、内容枯燥、学生学习兴趣较低、考核方式单调等... 详细信息

园艺植物研究法是我国高校为园艺专业开设的一门高级专业课,是为了培养学生独自开展科研的综合素养与能力。总结了该课程教学中存在的问题,主要包括课程教学与实验相分离、学生学习效果差、内容枯燥、学生学习兴趣较低、考核方式单调等。针对上述问题,从教学内容、教学方法、考核方式等方面分析了园艺植物研究法课程教学的改革措施,在实践教学中通过实施案例教学、引导学生主动探索问题等方法,提高学生课堂学习的积极性,从而提高课堂教学质量。

关键词：园艺植物研究法教学改革问题对策

Aerodynamic Modeling and Parameter Estimation from QAR Data of an Airplane Approaching a High-altitude Airport

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Chinese Journal of Aeronautics 2012年第3期25卷 361-371页

作者： WANG Qing WU Kaiyuan zhang Tianjiao KONG Yi'nan qian Weiqi State Key Laboratory of Aerodynamics.China Aerodynamics Research and Development Center Mianvang 621000.China Computational Aerodynamics Institute China Aerodynamics Research and Development Center Mianyang 621000 China Seientifie Research Base of Civil Aviation Flight Technology and Safety Guanghan 618307China

Aerodynamic modeling and parameter estimation from quick accesses recorder （QAR） data is an important technical way to analyze the effects of highland weather conditions upon aerodynamic characteristics of airplane. It is also an essential content of flight accident analysis. The related techniques are developed in the present paper, including the geometric method for angle of attack and sideslip angle estimation, the extended Kalman filter associated with modified Bryson-Frazier smoother （EKF-MBF） method for aerodynamic coefficient identification, the radial basis function （RBF） neural network method for aerodynamic mod- eling, and the Delta method for stability/control derivative estimation. As an application example, the QAR data of a civil air- plane approaching a high-altitude airport are processed and the aerodynamic coefficient and derivative estimates are obtained. The estimation results are reasonable, which shows that the developed techniques are feasible. The causes for the distribution of aerodynamic derivative estimates are analyzed. Accordingly, several measures to improve estimation accuracy are put forward.

关键词： civil airplane aerodynamics QAR data aerodynamic modeling aerodynamic parameter estimation flight safety EKF-MBF method neural network

Mechanical and biocompatible properties of polymer-infiltrated-ceramic-network materials for dental restoration

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Journal of Advanced Ceramics 2020年第1期9卷 123-128页

作者： Bencang CUI Ranran zhang Fengbo SUN qian DING Yuanhua LIN Lei zhang Cewen nan School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Department of Prosthodontics School and Hospital of StomatologyPeking UniversityBeijing 100081China

Dental restorative materials with high mechanical properties and biocompatible performances are *** this work,polymer-infiltrated-ceramic-network materials(PICNs)were fabricated via infiltrating polymerizable monomers into porous ceramic networks and incorporated with hydroxyapatite *** results revealed that the flexural strength can be enhanced up to 157.32 MPa,and elastic modulus and Vickers hardness can be achieved up to 19.4 and 1.31 GPa,respectively,which are comparable with the commercial computer-aided design and computer-aided manufacturing(CAD/CAM)***,the adhesion and spreading of rat bone marrow mesenchymal stem cells(r BMSCs)on the surface of such materials can be improved by adding hydroxyapatite,which results in good *** PICNs are potential applicants for their application in the dental restoration.

关键词： dental restoration hydroxyapatite polymer-infiltrated-ceramic-network materials(PICNs) mechanical property biocompatible performance

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石墨烯褶皱结构对双电层储能性能的理论研究

原子与分子物理学报 2025年第6期42卷 89-100页

作者：张倩蒋更平武汉科技大学理学院应用物理系武汉430081

石墨烯因其出色的比表面积和单层结构而被广泛认为是一种理想的电极材料.然而,实验制备的石墨烯常因官能团、缺陷和位错的引入而出现褶皱和变形.针对这一问题,本文构建了一系列具有不同幅度褶皱(a=0~6.6?)的石墨烯片,并运用分子动力学... 详细信息

石墨烯因其出色的比表面积和单层结构而被广泛认为是一种理想的电极材料.然而,实验制备的石墨烯常因官能团、缺陷和位错的引入而出现褶皱和变形.针对这一问题,本文构建了一系列具有不同幅度褶皱(a=0~6.6?)的石墨烯片,并运用分子动力学模拟来研究这些褶皱石墨烯表面的双电层结构.本研究旨在探讨不同褶皱高度和充电状态下双电层的变化规律,及其与超级电容器储能性能之间的关系.研究发现,褶皱石墨烯模型内部的离子浓度随电压的增加呈现多峰层状分布,而表面离子浓度与施加的电压正相关.此外,石墨烯的褶皱结构能够减少离子和水对电极电压响应的敏感性.在不同电压条件下,褶皱型石墨烯结构的面积比电容(C_A)始终高于其平面对应区域,突出了其在提升双电层储能性能上的优势.本研究揭示了石墨烯褶皱结构在调节离子分布、降低电压敏感性,以及增强电化学储能性能方面的特有作用机制.

关键词：双电层石墨烯褶皱恒电势模拟方法

Mediating role of health literacy in the relationship between social isolation and psychological distress among pre-frail older adults

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World Journal of Psychiatry 2025年第1期15卷 137-144页

作者： Juan Fang Li-Hui Li Ming-qian He Yue Ji Dong-Yan Lu Li-Bing zhang Jin-Lan Yao School of Medicine Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Frailty has become a significant public health *** recent increase in the number of frail older adults has led to increased attention being paid to psycho-logical care services in *** social isolation of pre-frail older adults can impact their psychological *** To explore the mediating effect of health literacy between social isolation and psychological distress among communitydwelling older adults with *** This descriptive cross-sectional study was conducted with 254 pre-frail older individuals aged 60 years and *** isolation,health literacy,and psycholo-gical distress were comprehensively measured using the Lubben Social Network Scale-6,12-item Short-Form Health Literacy Questionnaire,and the Kessler Psy-chological Distress *** were evaluated using the SPSS 27.0 package program and the PROCESS macro *** statistical analyses,correlation analyses,and bootstrap mediation tests were used to assess associations between the *** The results showed that social isolation had an effect on health literacy among pre-frail older adults(β=0.240,P<0.001),social isolation impact on psycho-logical distress pre-frail older adults(β=-0.415,P<0.001);health literacy was identified effect on psychological distress among pre-frail older persons(β=-0.307,P<0.001).Health literacy partially mediated the relationship between social isolation and psychological distress among community-dwelling older adults with pre-frailty,with a mediation effect of-0.074,accounting for 17.83%of the total effect.

关键词： Frail Ageing Psychological distress Health literacy Social isolation

Sulfur dioxide gas sensing at room temperature based on tin selenium/tin dioxide hybrid prepared via hydrothermal and surface oxidation treatment

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Rare Metals 2021年第6期40卷 1588-1596页

作者： qian-nan Pan Zhi-Min Yang Wei-Wei Wang Dong-Zhi zhang College of Control Science and Engineering China University of Petroleum(East China)Qingdao 266580China

In this paper,a novel SnSe/SnO_(2) nanoparticles(NPs) composite has been successfully fabricated through hydrothermal method and surface oxidation *** as-prepared sample was characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS) and transmission electron microscopy(TEM).A series of morphological and structural characteristics confirm that the SnSe/SnO_(2) NPs composite shows a core-shell structure with a SnO_(2) shell with thickness of 6 *** prepared SnO_(2) NPs and SnSe/SnO_(2) NPs composite were applied as gas-sensing materials,and their gas-sensing properties were investigated at room temperature *** results show that the response value of the SnSe/SnO_(2) composite sensor toward 100×10^(-6) SO_(2) is 15.15%,which is 1.32 times higher than that of pristine SnSe(11.43%).And the SnSe/SnO_(2) composite sensor also has a detection limit as low as 74×10^(-9) and an ultra-fast response *** enhanced gas-sensing performance is attributed to the formation of p-n heterojunction between SnSe and SnO_(2) and the appropriate SnO_(2) shell thickness.

关键词： SO_(2)gas sensor Room temperature detection Core-shell structure SnSe/SnO_(2)composite Debye length

Electron promoted ZnO for catalytic synthesis of higher alcohols from syngas

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Green Energy & Environment 2022年第6期7卷 1390-1400页

作者： Fang Li qian zhang Jing Liu nan Cui Guoqing Guan Wei Huang State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan030024ShanxiChina Energy Conversion Engineering Laboratory Institute of Regional Innovation(IRI)Hirosaki University2-1-3MatsubaraAomori030-0813Japan

Direct conversion of syngas from those non-petroleum carbon resources to higher alcohols are very attractive due to the process simplicity with low energy ***,the reaction always suffers from low yield as well as low ***,effective increase of higher alcohols proportion in the product is realized by direct conversion of syngas over electronically-modulated ZnO semiconductor via Cu *** is considered that the lower Fermi level and narrower band gap of catalysts by embedding Cu^(2+)into ZnO lattice could facilitate donor reaction by boosting the process for the reactants to obtain electrons on the catalyst surface for the formation of CH_(x) species and carbon chain growth,in which the Cu doping on ZnO lattice play important role in the promotion of CO *** a result,4 mol%Cu doped ZnO exhibits a highest C_(2+) OH/ROH fraction of 48.1%.Selectivity of catalysts from straight chain alcohol is better than from branch chain alcohol,which is different from promoted Cu/ZnO based ***,over-doping of Cu(7 mol%)on ZnO results in the aggregation Cu species on ZnO surface,leading to a sharp decrease of higher alcohols proportion to 3.2%.The results shed light on the nature that a direct correlation between semiconductor Fermi level and synthesis of higher alcohols,and the semiconductor-based catalysts mainly accelerate the hydrogenation reactions by enhancing thermally excited electron transfer.

关键词： Semiconductor catalysts Electron promotion Fermi level ZnO Higher alcohols

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生物炭对污染土壤修复的研究进展

辽宁化工 2020年第4期49卷 402-404+407页

作者：王欣钰高斯孙长龙张倩楠吴思沈阳师范大学

土壤是生物圈的重要组成部分,是人类生存和发展的基础,同时也是保障国家粮食安全的最基本的生产材料。随着人类社会经济的发展和人类活动的高度密集,土壤污染程度越来越严重。土壤质量持续恶化,严重影响人类健康,因此开展针对污染土壤... 详细信息

土壤是生物圈的重要组成部分,是人类生存和发展的基础,同时也是保障国家粮食安全的最基本的生产材料。随着人类社会经济的发展和人类活动的高度密集,土壤污染程度越来越严重。土壤质量持续恶化,严重影响人类健康,因此开展针对污染土壤的修复工作刻不容缓。生物炭作为一种在土壤改良、生物能源生产、有机废物循环利用和温室气体减排等方面具有积极意义的物质,对于农业应用方面有重要意义,引起了国内外研究者的广泛关注,成为近年来的研究热点之一。

关键词：生物炭土壤修复理化性质

Influence of laser re-melting and vacuum heat treatment on plasma-sprayed FeCoCrNiAl alloy coatings

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Journal of Iron and Steel Research International 2017年第12期24卷 1199-1205页

作者： Dan-yang Lin nan-nan zhang Bin He Bing-qian Jin Yue zhang De-yuan Li Fu-yu Dong Department of Material Science and Engineering Shenyang University of Technology Department of Pipeline Shenyang Institute of Special Equipment Inspection & Research

FeCoCrNiAl high entropy alloy coatings were prepared by supersonic air-plasma *** coatings were post-treated by vacuum heat treatment at 600 and 900°C,and laser re-melting with 300 W,respectively,to study the influence of different treatments on the structure and properties of the *** phase constitution,microstructure and microhardness of the coatings after treatments were investigated using X-ray diffraction,scanning electron microscopy and energy dispersive *** showed that the as-sprayed coatings consisted of pure metal and *** AlNi;phase was obtained after the vacuum heat treatment process.A body-centered cubic structure with less AlNi;could be found in the coating after the laser re-melting *** average hardness values of the as-sprayed coating and the coatings with two different temperature vacuum heat treatments and with laser re-melting were 177,227,266 and 682 HV,*** suggests that the vacuum heat treatment promoted the alloying process of the coatings,and contributed to the enhancement of the coating wear *** laser re-melted coating showed the best wear resistance.

关键词： Plasma spray High entropy alloy Vacuum heat treatment Laser re-melting FeCoCrNiAl alloy coating