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不同有机改良剂对盐碱地菊芋产量及土壤理化性质的影响

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山东农业科学 2024年第3期56卷 70-77页

作者：管西林郭洪海贾曦王璐边文范张玉凤董亮田慎重山东省农业科学院农业资源与环境研究所/养分资源高效利用全国重点实验室/农业农村部废弃物基质化利用重点实验室/农业农村部黄淮海平原农业环境重点实验室山东济南250100 山东省农业科学院黄河三角洲现代农业研究院山东东营257399

试验在黄河三角洲典型盐碱地上进行,以菊芋品种南芋1号为供试材料,设置不施肥对照(CK)、常规施肥(F)、商品有机肥(M)、生物炭基调理剂(T1)、抗盐调理剂(T2)共5个处理,研究不同有机改良剂对菊芋苗期生物量、块茎产量及土壤主要理化性质... 详细信息

试验在黄河三角洲典型盐碱地上进行,以菊芋品种南芋1号为供试材料,设置不施肥对照(CK)、常规施肥(F)、商品有机肥(M)、生物炭基调理剂(T1)、抗盐调理剂(T2)共5个处理,研究不同有机改良剂对菊芋苗期生物量、块茎产量及土壤主要理化性质的影响。结果表明:施用有机改良剂对盐碱地菊芋苗期干物质量和成熟期地下块茎产量影响显著,其中T1处理菊芋苗期干物质量和成熟期块茎产量最高,较CK、F处理分别显著提高76.4%、36.2%和38.7%、25.1%。与CK相比,T1处理菊芋苗期0~30 cm土层土壤pH值显著下降;M、T1和T2处理较CK和F处理显著降低菊芋苗期0~20 cm土层土壤水溶性盐含量,降幅达8.3%以上,且T1优于M和T2处理;菊芋收获后,M、T1和T2处理0~10 cm土层土壤有机质含量较CK分别显著提高15.1%、20.7%和21.0%,T1处理显著增加0~20 cm土层土壤碱解氮、有效磷和速效钾含量,M处理显著增加0~20 cm土层土壤有效磷和速效钾含量。综上,施用生物炭基调理剂对改良土壤盐碱化、促进壮苗培育、提高菊芋产量效果较优。

关键词：菊芋盐碱地有机改良剂块茎产量土壤理化性质黄河三角洲

Silicon-based micro direct methanol fuel cell with an N-inputs-N-outputs anode flow pattern

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Chinese Science Bulletin 2011年第8期56卷 826-829页

作者： zhang yufeng WANG LuWen YUAN ZhenYu WANG ShiBo LI JianMin LIU XiaoWei MEMS Center Harbin Institute of Technology Harbin 150001 China Key Laboratory of Micro-Systems and Micro-Structures Manufacturing Ministry of Education Harbin 150001 China

A micro direct methanol fuel cell(μDMFC) is suitable for use in notebook computers,mobile phones,and other digital *** resolve the poor mass-transport efficiency problem in the anode flow channel,this paper presents an N-inputs-N-outputs parallel flow pattern with rectangular convexes to reinforce methanol mass transport and reduce concentration *** simulation results show that the N-inputs-N-outputs parallel flow channels with the rectangle convexes improve the performance.μDMFCs,which have four anode flow patterns,are fabricated using MEMS(microelectromechanical systems) *** experimental results show that the μDMFC with the rectangle convexes has a performance better than previously reported systems,and has a peak power density of 19.96 mW/*** simulation and experimental results are in good agreement.

关键词：直接甲醇燃料电池输入阳极输出微型硅基仿真结果笔记本电脑

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桥梁轻量化监测技术赋能交通强国

质量与认证 2024年第1期 74-75页

作者：徐一超张宇峰韩依璇苏交科集团股份有限公司

桥梁轻量化监测是一种重点面向桥梁应用场景需求,对桥梁特定参数进行专项监测,获取定量数据或定性结果,实现超限报警预警和长期数据跟踪观测,服务桥梁运营养护的多学科交叉融合技术。该技术可实现实时数据异常报警和长期数据跟踪观测,... 详细信息

桥梁轻量化监测是一种重点面向桥梁应用场景需求,对桥梁特定参数进行专项监测,获取定量数据或定性结果,实现超限报警预警和长期数据跟踪观测,服务桥梁运营养护的多学科交叉融合技术。该技术可实现实时数据异常报警和长期数据跟踪观测,服务公路桥梁的智慧化运维和科学化管养。本文介绍了桥梁轻量化监测技术发展过程、技术攻关及应用,阐释了该技术支撑交通强国建设的重要作用。

关键词：轻量化监测场景需求低功耗高集成智慧运维

Exploring a balance between strength and ductility of hexagonal BN nanoplatelet reinforced ZK61 magnesium composite

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Journal of Magnesium and Alloys 2024年第5期12卷 1899-1910页

作者： Kewei zhang Xiaolong Lu yufeng Sun Shaokang Guan Yao Chen School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Advanced Magnesium Alloys in Henan Province Zhengzhou UniversityZhengzhou 450002China Key Laboratory of Advanced Materials Processing&Mold Ministry of EducationZhengzhou 450002China School of Mechanical and Electrical Engineering Soochow UniversitySuzhou 215021China

The practical applications of magnesium(Mg)alloys are usually beset by their relatively low strength and limited *** we attempt to fabricate hexagonal BN nanoplatelet(BNNP)reinforced ZK61 magnesium composites using a combination of spark plasma sintering and friction stir *** resulting composites exhibit microstructural characteristics of homogeneous dispersion of BNNP in Mg matrix with refined equiaxed grains and(0002)basal texture roughly surrounding the pin column *** electron microscopy observation illustrates that trace amounts of Mg_(3)N_(2)and MgB_(2)form at BNNP-Mg interface,in which Mg_(3)N_(2)locates at the basal plane of a BNNP and MgB_(2)grows at its open *** spatial distribution of Mg_(3)N_(2)and MgB_(2)facilitates interfacial wetting and stronger BNNP-Mg interface in such a way that interfacial products act as anchors bonding between *** comparison with monolithic ZK61 alloy,the BNNP/ZK61 composites display simultaneous improvements in yield strength,hardness and ductility,achieving good strength-ductility *** research is expected to shed some light on BNNP potentials for designing and producing magnesium composites with high strength and good ductility.

关键词： BN nanoplatelet Magnesium composite Strength Ductility Spark plasma sintering Friction stir processing

Constitutive model of viscoelastic dynamic damage for the material of gas obturator in modular-charge howitzer

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Defence Technology（防务技术） 2024年第9期39卷 203-216页

作者： Zhonggang Li Longmiao Chen Yifan Li yufeng Jia Quan zhang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China Technology Center Shanxi North Machine-building Co.Ltd.Taiyuan 030009China Research and Development Department Kelong New Material Technology Co.Ltd.Xianyang 712000China

In order to investigate the mechanical response behavior of the gas obturator of the breech mechanism,made of polychloroprene rubber(PCR), uniaxial compression experiments were carried out by using a universal testing machine and a split Hopkinson pressure bar(SHPB), obtaining stress-strain responses at different temperatures and strain rates. The results revealed that, in comparison to other polymers, the gas obturator material exhibited inconspicuous strain softening and hardening effects;meanwhile, the mechanical response was more affected by the strain rate than by temperature. Subsequently, a succinct viscoelastic damage constitutive model was developed based on the ZWT model, including ten undetermined parameters, formulated with incorporating three parallel components to capture the viscoelastic response at high strain rate and further enhanced by integrating a three-parameter Weibull function to describe the damage. Compared to the ZWT model, the modified model could effectively describe the mechanical response behavior of the gas obturator material at high strain rates. This research laid a theoretical foundation for further investigation into the influence of chamber sealing issues on artillery firing.

关键词： Breech mechanism Gas obturator Polychloroprene rubber Constitutive model Strain rate Damage

Source apportionment and ecological risk assessment of PAHs in surface sediments from the Liaodong Bay,northern China

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Acta Oceanologica Sinica 2018年第4期37卷 12-21页

作者： zhang yufeng WU Jinhao SONG Lun SONG Yonggang YANG Meng WANG Nianbin HAN Jiabo GUAN Daoming College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China Liaoning Ocean and Fisheries Science Research Institute Dalian 116023 China Liaoning Ocean Environment Monitoring Station Dalian 116023 China Dalian Environmental Monitoring Center Dalian 116023 China National Marine Environmental Monitoring Center Dalian 116023 China

The sources and ecological risk from sixteen polycyclic aromatic hydrocarbons in surface sediment in the Liaodong Bay were investigated from 2014 to *** total concentrations of PAHs ranged from 88.5 to 347.1 ng/g,and the high value occurred in the central region of the Liaodong *** analysis identified two site clusters representing the coastal region affected by land-based pollution and the central region of the Liaodong *** component analysis-multiple linear regression and diagnostic ratios suggested that PAHs contaminants originated from a mixture of combustion and petroleum sources,and the major was combustion *** on sediment quality guideline,naphthalene,acenaphthylene,acenaphthene,phenanthrene and dibenz[a,h]anthracene may occasionally cause adverse biological effects in some *** toxic equivalent concentrations of carcinogenic PAHs indicated low carcinogenic risk for the Liaodong *** ecological risk and toxic pollution levels of PAHs were higher in the central region than in the coastal region along the Liaodong Bay.

关键词： polycyclic aromatic hydrocarbons Liaodong Bay source apportionment ecological risk assessment,sediment

基于自适应尺度混合海森滤波器的面部皱纹检测及评分

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应用科技 2024年第2期51卷 24-30页

作者：冯月宝平何冰冰郭振宇张梅马骁张榆锋云南大学信息学院云南昆明650091 云南贝泰妮生物科技集团股份有限公司云南昆明650090

为解决全面部皱纹缺乏量化评价方法的问题,提出了一种基于自适应尺度混合海森滤波器(adaptive scale hybrid Hessian filter,ASHHF)的面部皱纹检测方法及评分机制。根据受试者年龄自适应调整海森滤波器的尺寸(σ)范围及步长参数并对其... 详细信息

为解决全面部皱纹缺乏量化评价方法的问题,提出了一种基于自适应尺度混合海森滤波器(adaptive scale hybrid Hessian filter,ASHHF)的面部皱纹检测方法及评分机制。根据受试者年龄自适应调整海森滤波器的尺寸(σ)范围及步长参数并对其面部高分辨率图像进行滤波,基于81个面部特征点在滤波结果中去除五官、背景,仅保留面部皱纹,使用不同颜色将不同深度的皱纹检测结果标注在原始图像中,最后计算得分量化皮肤衰老程度。以专业医生标注皱纹为参考,50名受试者(年龄为22~65岁)的检测结果表明,相比于传统的固定尺度混合海森滤波器(fixed scale hybrid Hessian filter,FSHHF),ASHHF方法的检测准确率平均提升68.57%,运行时间平均缩短26.26%,评分机制结果与检测准确率的变化趋势一致。综上,本文检测方法能够准确、快速检测面部皱纹分布、深度及宽度,所提评分机制能够科学反映受试者皮肤衰老程度,有望为化妆品、医疗美容等抗衰方法提供功效量化评价手段。

关键词：皮肤衰老面部皮肤皱纹检测皱纹识别皱纹评分机制混合海森滤波器自适应尺度年龄

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Optimal geometrical configuration and oxidation state of cobalt cations in spinel oxides to promote the performance of Li-O_(2) battery

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Nano Research 2024年第1期17卷 221-227页

作者： Yu zhang Shuting zhang Mengwei Yuan yufeng Li Rong Liu Caiyun Nan Chen Chen Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875China X-ray diffraction Lab Analytical and Testing CenterBeijing Normal UniversityBeijing 100875China

Co_(3)O_(4) is considered as one of promising cathode catalysts for lithium oxygen(Li-O_(2))batteries,which contains both tetrahedral Co^(2+)sites(Co^(2+)Td)and octahedral Co^(3+)sites(Co^(3+)Oh).It is important to reveal the effect of optimal geometric configuration and oxidation state of cobalt ion in Co_(3)O_(4) to improve the performance of Li-O_(2) ***,through regulating the synthesis process,Co^(2+)and Co^(3+)sites in Co_(3)O_(4) were replaced with Zn and Al atoms to form materials with a unique Co *** Li-O_(2) batteries based on ZnCo_(2)O_(4) showed longer cycle life than that of CoAl_(2)O_(4),suggesting that in Co_(3)O_(4),the Co^(3+)Oh site is a relatively better geometric configuration than Co^(2+)Td site for Li-O_(2) *** calculations revealed that Co^(3+)Oh sites provide higher catalysis activity,regulating the adsorption energy of the intermediate LiO_(2) and accelerating the kinetics of the reaction in batteries,which further leads to the change of the morphology of the discharge product and ultimately improves the electrochemical performance of the batteries.

关键词： lithium oxygen(Li-O_(2))batteries geometrical configuration oxidation state lithium peroxide

Evaluation of the Effectiveness of the “1 + 1 + 1” Method in Theoretical Teaching of Emergency Pericardiocentesis

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