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基于离散元的设施农业就地翻土犁的研究与试验

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吉林大学学报（工学版） 2024年第4期54卷 1153-1165页

作者：刘元义于圣洁胥备王宪良宋发成山东理工大学农业工程与食品科学学院山东淄博255000 西安交通大学机械制造系统国家重点实验室西安710054

针对设施农业空间狭小,土壤病虫害严重,无法使用铧式犁深翻的问题,提出一种就地翻土解决办法。根据逆向工程得到就地翻土犁犁体逆向曲面,通过现有犁体成型原理,参照铧式犁犁体耕宽、耕深、犁体安装角、切土角、导曲线提升角、开度、犁... 详细信息

针对设施农业空间狭小,土壤病虫害严重,无法使用铧式犁深翻的问题,提出一种就地翻土解决办法。根据逆向工程得到就地翻土犁犁体逆向曲面,通过现有犁体成型原理,参照铧式犁犁体耕宽、耕深、犁体安装角、切土角、导曲线提升角、开度、犁体长度等参数,创设就地翻土犁犁体正向曲面;实测设施农业土壤相对湿度为34.57%、土壤堆积角为39°,通过EDEM软件中的接触参数数据库GEMM得到接触参数范围,标定土壤颗粒间表面能为4.19 J/m^(2)、碰撞恢复系数为0.282、动摩擦因数为0.051、静摩擦因数为0.629,创设试验土槽;引入原沟落土率概念;构建原沟落土率与曲面参数间的相互作用模型,得到最佳原沟落土率曲面参数;利用Design-Expert软件进行分析,以原沟落土率为响应指标,使用Plackett-Burman试验设计方法开展多因素两水平显著性筛选试验,得到影响原沟落土率耕宽、犁铧安装角、切土角3个显著性因素;对3因素进行Box-Behnken试验设计,得到278.392 mm耕宽、40.522°犁铧安装角、23.211°切土角最佳设计参数。针对优化结果进行试验,得到试验结果与预测结果误差为3.13%,试验结果表明,所研究就地翻土犁可以达到就地翻垡的目的,并为解决设施农业内土壤深翻问题提供参考。

关键词：农业工程就地翻土犁正交试验原沟落土率实物试验

基于化学学科核心素养的解决问题关键能力测评框架的构建与应用

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化学教育（中英文） 2024年第5期45卷 29-34页

作者：周瑶王西宇余淞发申燕廖春泉深圳外国语学校广东深圳518083 深圳市第二十二高级中学广东深圳518107 深圳市盐港中学广东深圳518083 深圳市教育科学研究院广东深圳518001 广州大学化学化工学院广东广州510006 南方科技大学附属中学广东深圳518109

基于《普通高中化学课程标准(2017年版2020年修订)》中化学学科核心素养水平和学业水平考试的命题建议,本研究以知识(Knowledge)输出水平和情境(Situation)加工水平相融合的视角分析描述学生在解决实际问题(Question)过程中所表现的关... 详细信息

基于《普通高中化学课程标准(2017年版2020年修订)》中化学学科核心素养水平和学业水平考试的命题建议,本研究以知识(Knowledge)输出水平和情境(Situation)加工水平相融合的视角分析描述学生在解决实际问题(Question)过程中所表现的关键能力(Ability),构建了“KS-Q-A”能力测评框架,并以该测评框架对2023年深圳市高三年级化学学科第一次调研考试的试题进行分析,测评诊断学生的能力水平,也进一步佐证了测评框架的合理性和科学性。

关键词：化学测评知识输出情境加工关键能力

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海水泵可靠性设计与使用管理探讨

阀门 2024年第3期 383-386页

作者：童法松王树森海装沈阳局驻鞍山地区军事代表室辽宁鞍山114001

海水泵为柴油发电机组冷水系统提供冷媒海水循环的动力。除了冷却海水泵的机泵功能要求外,根据现代机械设计理论及舰船主要设备维护管理条例,对舰船用冷却海水泵进行了可靠性预计,并提出了几项重点要求。在满足冷却海水泵功能实现的基础... 详细信息

海水泵为柴油发电机组冷水系统提供冷媒海水循环的动力。除了冷却海水泵的机泵功能要求外,根据现代机械设计理论及舰船主要设备维护管理条例,对舰船用冷却海水泵进行了可靠性预计,并提出了几项重点要求。在满足冷却海水泵功能实现的基础上,要求保证冷却海水泵达到可靠性要求。同时提出了冷却海水泵使用现场应具备的保障条件和冷却海水泵日常使用的相关现场管理规程。为舰船用冷却海水泵的合理设计和正确使用管理提供了理论依据。

关键词：冷却海水泵可靠性预计关重件现场管理

Study on the Vibration Reduction Characteristics of FWMAV Flexible Bionic Wings Mimicking the Hindwings of Trypoxylus dichotomus

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Journal of Bionic Engineering 2023年第5期20卷 2179-2193页

作者： Yongwei Yan fa song Nuo Xu Haochen Zhu Hongxu Xing Shujun Zhang Jiyu Sun Key Laboratory of Bionic Engineering(Ministry of Education China)Jilin UniversityChangchun130022China School of Computing and Engineering Gloucestershire UniversityCheltenhamGL502HRUK

Using the method of structural finite element topology optimization and analysis of the hindwings of Trypoxylus dichotomus,this work identified the main loading force transmission path and designed the initial structure of a bionic flexible wing.A structural design scheme of the vibration damping unit was proposed,and the structural mechanics and modal vibration characteristics were simulated and analyzed.3D printing technology was used to manufacture the designed bionic wing skeleton,which was combined with two kinds of wing membrane *** Flapping Wing Micro-aerial Vehicle(FWMAV)transmission mechanism vibration characteristics were observed and analyzed by a high-speed digital camera.A triaxial force transducer was used to record the force vibration of the flexible bionic wing flapping in a wind tunnel.A wavelet processing method was used to process and analyze the force *** results showed that the force amplitude was more stable,the waveform roughness was the lowest,and the peak shaving phenomenon at the z-axis was the least obvious for the bionic flexible wing model that combined the topology-optimized bionic wing skeleton with a polyamide elastic *** was determined to be the most suitable design scheme for the wings of FWMAVs.

关键词： Vibration reduction characteristics Bionic wings Flapping-wing micro-aerial vehicle(FWMAV) Beetle hindwings

基于NF-κB通路研究平肝活血合剂对脑缺血再灌注损伤的作用机制

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中南药学 2024年第4期22卷 902-907页

作者：刘宗梅王晓玲宋发萍姚硕唐勇陕西中医药大学第一临床医学院陕西咸阳712046 安康市中医医院陕西安康725000

目的探讨平肝活血合剂对脑缺血再灌注损伤(CIRI)的作用机制。方法采用线栓法制备CIRI模型。SD大鼠随机分为假手术组,模型组,平肝活血合剂低、中、高剂量组(2.08、4.16、8.32 mL·kg^(-1)),阳性对照组(丁苯酞软胶囊6.25 mg·kg^(-1)),... 详细信息

目的探讨平肝活血合剂对脑缺血再灌注损伤(CIRI)的作用机制。方法采用线栓法制备CIRI模型。SD大鼠随机分为假手术组,模型组,平肝活血合剂低、中、高剂量组(2.08、4.16、8.32 mL·kg^(-1)),阳性对照组(丁苯酞软胶囊6.25 mg·kg^(-1)),每组10只。灌胃治疗7d,每日1次。造模后第1、3、7日观察大鼠神经功能评分。给药7日后观察大鼠脑缺血组织病理改变,测定脑梗死体积百分比,检测血清肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、白细胞介素-8(IL-8)的水平,脑缺血组织中的TNF-α、IL-1β、IL-8 mRNA表达,脑缺血组织中磷酸化的NF-κB抑制蛋白α(p-IκBα)、核转录因子-κBp65(NF-κBp65)、磷酸化的核转录因子-κBp65(p-NF-κBp65)蛋白的表达。结果与假手术组比较,模型组大鼠给药7日后Longa评分显著升高,右脑出现鲜明的苍白色梗死灶(P <0.01),TNF-α、IL-1β、IL-8及TNF-α、IL-1β、IL-8 mRNA表达均显著上升,p-IκBα、NF-κBp65、p-NF-κBp65蛋白表达均明显上调(P <0.05或P <0.01)。HE染色显示脑缺血组织区网状结构疏松,细胞错乱、结构缺损甚至萎缩变形、数量变少,核固缩及碎裂。与模型组比较,给药7日后平肝活血合剂各剂量组Longa评分显著降低,其余检测指标亦明显下降(P <0.05或P <0.01)。结论平肝活血合剂可显著改善CIRI的炎症因子水平,减轻脑损伤,其机制可能与调控NF-κB信号通路有关。

关键词：平肝活血合剂脑缺血再灌注损伤炎症抑制 NF-κB信号通路

Generating electron spin qubit in metal-organic frameworks via spontaneous hydrolysis

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Chinese Chemical Letters 2024年第7期35卷 529-533页

作者： Xian-fa Jiang Chongyun Shao Zhongwen Ouyang Zhao-Bo Hu Zhenxing Wang You song State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Wuhan National High Magnetic Field Center&School of Physics Huazhong University of Science and TechnologyWuhan 430074China Chaotic Matter Science Research Center Faculty of Materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou 341000China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

Qubit,as the basic unit of quantum operations,has at least two quantum states for *** itself has no superimposable quantum states,but after injecting N atoms,the resulted nitrogenvacancy centers form excellent-performance *** the same purpose,we can also obtain qubits by modifying the matrix without effective quantum ***-1({Cu_(3)(BTC)_(2)(H_(2)O)_(3)},BTC=1,3,5-benzene-tricarboxylate)with S=0 ground state is electron paramagnetic resonance(EPR)silent,so it is not a qubit ***,the spontaneously hydrolyzed HKUST-1 produces dilute uncoupled Cu^(Ⅱ)ions with S=1/*** this paper,we utilized the hydrolysis products of HKUST-1 to obtain qubits and assembled a core-shell structural HKUST-1@ZIF-8 by ZIF-8({Zn(mim)_(2)},mim=2-methylimidazole)coated over HKUST-1 for controlling the *** experimental results clearly show that the qubits come from hydrolyzed Cu^(Ⅱ)***,the dilute uncoupled Cu^(Ⅱ)ions in this assembly can effectively reduce the decoherence of *** EPR studies show that the T_(2) of this compound is 1067 ns at 10 K.

关键词： Hydrolysis Qubit Decoherent times Metal-organic framework Core-shell structure

Optimization of the co-closing law of guide vanes and blades for bulb turbines based on CFD

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Journal of Hydrodynamics 2024年第2期36卷 363-377页

作者： Hui Liu Yun-fa Lin Yong-guang Cheng song Xue Mao-jia Tang Jian Zhang Jia-yi fan State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China Dongfang Electric Machinery Co. Ltd.Deyang618000China

The load rejection transient process of bulb turbine units is critical to safety of hydropower stations,and determining appropriate closing laws of guide vanes(GVs)and runner blades(RBs)for this process is of *** this study,we proposed a procedure to optimize the co-closing law of GVs and RBs by using computational fluid dynamics(CFD),combined with the design of experiment(DOE)method,approximation model,and genetic optimization *** sensitivity of closing law parameters on the histories of head,speed,and thrust was analyzed,and a two-stage GVs’closing law associating with a linear RBs’closing law was *** results show that GVs dominate the transient characteristics by controlling the change of *** GVs’first-stage closing speed while shortening first-stage closing time can not only significantly reduce the maximum rotational speed but also suppress the water hammer pressure;slowing GVs’second-stage closing speed is conducive to controlling the maximum reverse axial *** directly affect the runner *** RBs’closing speed can further reduce the rotational speed and the maximum reverse axial *** safety margin of each control parameter,flow patterns,and pressure pulsations of a practical hydropower station were all improved after optimization,demonstrating the effectiveness of this method.

关键词： Bulb turbine load rejection transient process double regulation closing law optimization computational fluid dynamics(CFD)

Pollen and Resource Limitation in Veratrum nigrum L. （Liliaceae）, an Andromonoecious Herb

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Journal of Integrative Plant Biology 2006年第12期48卷 1401-1408页

作者： Wan-Jin Liao Qing-fa song Da-Yong Zhang Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering and Institute of Ecology Beijing Normal University Beijing 100875 China

Pollen limitation and resource limitation were invoked to account for the pattern that flowering plants produce more flowers and ovules than fruits and seeds. This study aimed to determine their relative importance in Veratrum nigrum, a self-compatible, perennial, andromonoecious herb. In order to determine whether female production was limited by pollen grains on stigmas or by available resources, we performed supplemental hand pollination in three populations, male-flower-bud removal in three other populations, and emasculation of hermaphroditic flowers in still another population, resulting in a total of seven populations experimentally manipulated. Across the three populations, supplemental hand pollination did not significantly increase fruit set, seed number per fruit, and total seed production per individual, nor did emasculation of hermaphroditic flowers. Taken together, our results suggest that pollen grains deposited on stigmas were abundant enough to fertilize all the ovules. Male-flower-bud removal significantly increased the mean size of hermaphroditic flowers in all three populations. Female reproductive success was increased in one population, but not in the other two populations possibly due to heavy flower/seed predation. We concluded that the female reproductive success of V. nigrum was not limited by pollen grains but by available resources, which is consistent with Bateman＇s principle. Furthermore, the female reproduction increase of male-flower-bud removal individuals might suggest a trade-off between male and female sexual functions.

关键词： andromonoecy pollen limitation resource limitation trade-off Veratrum nigrum

Role of the extracellular matrix in COVID-19

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World Journal of Clinical Cases 2023年第1期11卷 73-83页

作者： Jia-Jia Huang Chu-Wen Wang Ying Liu Ying-Ying Zhang Nai-Bin Yang Yu-Chun Yu Qi Jiang Qi-fa song Guo-Qing Qian School of Medicine Ningbo UniversityNingbo 315000Zhejiang ProvinceChina Department of Infectious Diseases Ningbo First HospitalNingbo 315000Zhejiang ProvinceChina Department of Endocrinology Ningbo Ninth HospitalNingbo 315000Zhejiang ProvinceChina Department of Digestive Ningbo First HospitalNingbo 315000Zhejiang ProvinceChina Medical Data Center Ningbo First HospitalNingbo 315000Zhejiang ProvinceChina

An outbreak of coronavirus disease 2019(COVID-19)has spread globally,with over 500 million cases and 6 million deaths to ***-19 is associated with a systemic inflammatory response and abnormalities of the extracellular matrix(ECM),which is also involved in inflammatory *** viral infection,ECM proteins are involved in the recruitment of inflammatory cells and interference with target organ metabolism,including in the ***,serum biomarkers of ECM turnover are associated with the severity of COVID-19 and may serve as potential ***,understanding the expression and function of ECM,particularly of the lung,during severe acute respiratory syndrome of the coronavirus 2 infection would provide valuable insights into the mechanisms of COVID-19 *** this review,we summarize the current findings on ECM,such as hyaluronic acid,matrix metalloproteinases,and collagen,which are linked to the severity and inflammation of *** drugs targeting the extracellular surface have been *** the future,these ECM findings could provide novel perspectives on the pathogenesis and treatment of COVID-19.

关键词： COVID-19 SARS-CoV-2 Extracellular Matrix Inflammation