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Al⁃LiH复合燃料制备及性能

含能材料 2024年第1期32卷 12-19页

作者：王芳张鑫鹏王鼎程李春涛孙鑫科冯勇李伟航天化学动力技术重点实验室湖北襄阳441003 湖北航天化学技术研究所湖北襄阳441003

为了提高铝粉燃烧效率,利用球磨法分别制备了质量含量为3%,5%,10%,15%的Al‐LiH复合燃料。通过X射线衍射仪(XRD)、扫描电镜(SEM)、粒度仪对样品结构、形貌和粒径进行表征;采用差热‐热重量热仪对其热氧化性能进行表征,最后采用CO_(2)激... 详细信息

为了提高铝粉燃烧效率,利用球磨法分别制备了质量含量为3%,5%,10%,15%的Al‐LiH复合燃料。通过X射线衍射仪(XRD)、扫描电镜(SEM)、粒度仪对样品结构、形貌和粒径进行表征;采用差热‐热重量热仪对其热氧化性能进行表征,最后采用CO_(2)激光点火装置、高速摄像机及氧弹量热仪对其燃烧性能进行考察。结果表明:通过球磨法可以将LiH嵌入Al粉内部,LiH含量是影响其微观形貌及粒径、粒径分布的关键因素,LiH的加入使得燃料质量热值增加,同时随着LiH含量的增加Al‐LiH复合燃料燃烧火焰强度增强,点火延迟时间大幅降低。其中由于Al‐LiH复合燃料在高温下发生了微爆现象,Al‐3LiH和Al‐10LiH复合燃料在一次氧化后分别实现第二次氧化。

关键词：铝粉氢化锂推进剂燃烧性能

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浅论近年来中国扶贫剧的结构新变与叙事突围

徐州工程学院学报（社会科学版） 2024年第2期39卷 28-34页

作者：孙可欣郑鹏辽宁大学文学院辽宁沈阳110000 安阳师范学院文学院河南安阳455000

近年来,我国陆续出现讲述“脱贫攻坚”工作的现实主义题材电视剧。这些扶贫剧在叙事结构中建立起诸多相似的“三角模式”,即通过对三类人物角色的形塑建构起相对闭合而又具有流动属性的叙事冲突。在此基础上,可进一步剖析扶贫剧在叙事... 详细信息

近年来,我国陆续出现讲述“脱贫攻坚”工作的现实主义题材电视剧。这些扶贫剧在叙事结构中建立起诸多相似的“三角模式”,即通过对三类人物角色的形塑建构起相对闭合而又具有流动属性的叙事冲突。在此基础上,可进一步剖析扶贫剧在叙事模式建构上的新变,发掘其中充分利用影像视听语言营造的富有乡土情怀的现实主义多元景观。与此同时,扶贫剧通过扶贫主体的觉醒与确立,传达当下社会价值体系与意识形态观念,进而完成了将个人身份认同与地方性书写逐渐融合进想象共同体的扶贫叙事。

关键词：扶贫剧三角模式扶贫景观价值导向

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丁羟三组元推进剂的增材制造及性能研究

火炸药学报 2024年第2期47卷 172-179,I0003页

作者：孙鑫科石柯史钰罗聪王鼎程李伟任全彬航天化学动力技术重点实验室湖北襄阳441003 湖北航天化学技术研究所湖北襄阳441003 航天动力技术研究院陕西西安710025

针对传统浇注成型与直写式3D打印对固体推进剂药浆工艺性能要求相冲突的问题,为实现小型药柱的3D打印,采用添加少量定型助剂(YJ)的方法对丁羟三组元推进剂配方进行改性,对改性前后推进剂的工艺性能、力学性能、燃烧性能和能量性能进行... 详细信息

针对传统浇注成型与直写式3D打印对固体推进剂药浆工艺性能要求相冲突的问题,为实现小型药柱的3D打印,采用添加少量定型助剂(YJ)的方法对丁羟三组元推进剂配方进行改性,对改性前后推进剂的工艺性能、力学性能、燃烧性能和能量性能进行对比分析,并探究了YJ对推进剂性能的影响。结果表明,改性后的推进剂药浆具备可控挤出和室温堆积的流变特性;YJ的加入使得推进剂在20、70℃下的最大抗拉强度分别降低0.1和0.15 MPa,断裂伸长率分别增加了12.7%和9.9%,表明YJ对其力学性能影响显著;此外,实验及理论计算表明,YJ对推进剂的燃烧性能和能量性能影响甚微,燃速最大降低0.24 mm/s,能量变化幅度均在1%以内;表明定型助剂(YJ)的加入不仅使药浆满足3D打印要求,而且对原始推进剂的整体性能没有显著负面影响。

关键词：复合固体推进剂丁羟三组元推进剂增材制造力学性能流变特性燃烧性能 3D打印

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A Dietary Supplement Jinghuosu Ameliorates Reproductive Damage Induced by Tripterygium Glycosides

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Chinese Journal of Integrative Medicine 2024年第4期30卷 330-338页

作者： MA Jing sun Bo TE Li-ger HUANG xin ZUO xin HAN Xiao-ke WANG Shu-song Hebei key Laboratory of Reproductive Medicine Hebei Institute of Reproductive HealthHebei Reproductive Health HospitalShijiazhuang(050071)China Graduate School of Hebei Medical University Shijiazhuang(050017)China School of Chemistry and Materials Science Hebei Normal UniversityShijiazhuang(050024)China xingtai Infertility Specialist Hospital XingtaiHebei Province(054000)China

Objective To determine the possible protective effects of Jinghuosu,a dietary supplement(DS),on tripterygium glycosides(TG)-induced reproductive system injury in rats and its underlying *** A reproductive damage model was established in rats by feeding of ***-eight male Sprague Dawley rats were randomly divided into 4 groups using a random number table(n=7 in each):control(C)group,model(M)group,DS group and L-carnitine(LC)*** in M,DS and LC groups received 40 mg/kg TGs *** from the 5th week,after administration of TGs for 4 h every day,rats in DS and LC groups were administered with 2.7 g/kg DS and 0.21 g/kg LC,respectively,for protective treatment over the next 4 *** in Group C continued to receive the control ***-eosin staining was used for histopathological analysis of rat testicular ***-linked immunosorbent assay was performed to measure alkaline phosphatase(ALP),lactate dehydrogenase,alcohol dehydrogenase,total antioxidant capacity(T-AOC),superoxide dismutase,glutathione peroxidase(GSH-Px),and malondialdehyde(MDA)*** assay was used to determine the serum testosterone *** real-time PCR and Western blotting were conducted to analyze the expression of genes and proteins related to the testosterone synthesis pathway and the nuclear factor erythroid 2-related factor 2/heme oxygenase 1 antioxidant *** Oral administration of TGs induced significant increases in the testicular levels of zinc transporter 1 and MDA(Pke protein 1,ALP,luteinizing hormone(LH)receptor,steroidogenic acute regulatory protein,Cytochrome P450 family 11 subfamily A member 1,3β-hydroxysteroid dehydrogenase 1 T-AOC,GSH-Px,nuclear factor erythroid 2-related factor 2,heme oxygenase-1 and NAD(P)H:quinone oxidoreductase 1 levels decreased following TG

关键词： dietary supplement Jinghuosu tripterygium glycosides reproductive damage infertility

Love wave propagation in one-dimensional piezoelectric quasicrystal multilayered nanoplates with surface effects

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 619-632页

作者： xin FENG Liaoliang ke Yang GAO College of Science China Agricultural UniversityBeijing 100083China School of Mechanical Engineering Tianjin UniversityTianjin 300350China

The exact solutions for the propagation of Love waves in one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)nanoplates with surface effects are *** electro-elastic model is developed to investigate the anti-plane strain problem of Love wave *** introducing three shape functions,the wave equations and electric balance equations are decoupled into three uncorrelated *** the boundary conditions of the top surface on the covering layer,the interlayer interface,and the matrix,a dispersive equation with the influence of multi-physical field coupling is provided.A surface PQC model is developed to investigate the surface effects on the propagation behaviors of Love waves in quasicrystal(QC)multilayered structures with nanoscale thicknesses.A novel dispersion relation for the PQC structure is derived in an explicit closed form according to the non-classical mechanical and electric boundary *** examples are given to reveal the effects of the boundary conditions,stacking sequence,characteristic scale,and phason fluctuation characteristics on the dispersion curves of Love waves propagating in PQC nanoplates with surface effects.

关键词： piezoelectric quasicrystal(PQC)material multilayered plate dispersion characteristic surface effect

Strong Edge Coloring of Outerplane Graphs with Independent Crossings

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 467-477页

作者： ke-Jie LI xin ZHANG School of Mathematics and Statistics Xidian UniversityXi’an 710071China

The strong chromatic index of a graph is the minimum number of colors needed in a proper edge coloring so that no edge is adjacent to two edges of the same *** outerplane graph with independent crossings is a graph embedded in the plane in such a way that all vertices are on the outer face and two pairs of crossing edges share no common end *** is proved that every outerplane graph with independent crossings and maximum degreeΔhas strong chromatic index at most 4Δ-6 if Δ≥4,and at most 8 ifΔ≤*** bounds are sharp.

关键词： outer-1-planar graph IC-planar graph strong edge coloring crossing

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Dominant woody plant species recognition with a hierarchical model based on multimodal geospatial data for subtropical forests

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Journal of Forestry Research 2024年第3期35卷 111-130页

作者： xin Chen Yujun sun State Forestry&Grassland Administration key Laboratory of Forest Resources&Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been widely used,leading to a wealth of valuable ***,the potential of GEE for forest resource management has not been fully *** extract dominant woody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data with the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast *** and texture features,red-edge bands,and vegetation indices of S1 and S2 data were computed.A hierarchical model obtained information on forest distribution and area and the dominant woody plant *** results suggest that combining data sources from the S1 winter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source ***,for dominant woody species recognition,using S1 winter and S2 data across all four seasons was *** terrain factors and removing spatial correlation from NFRI sample points further improved the recognition *** optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(MICE)of 96.7%.OA and MICE were 83.6%and 80.7%for dominant species extraction,*** high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely well for extracting information about dominant woody plant *** the results using the GEE application allows for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

关键词： Google Earth Engine Sentinel Forest resource inventory data Dominant woody plant species Subtropics Model performance

Incidence Coloring of Outer-1-planar Graphs

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 840-848页

作者： Meng-ke QI xin ZHANG School of Mathematics and Statistics Xidian UniversityXi'an 710071China

A graph is outer-1-planar if it can be drawn in the plane so that all vertices lie on the outer-face and each edge crosses at most one another *** is known that every outer-1-planar graph is a planar *** this paper,we conjecture that every planar graph G has a proper incidence(Δ(G)+2)-coloring and confirm it for outer-1-planar graphs with maximum degree at least 8 or with girth at least ***,we prove that every outer-1-planar graph G has an incidence(Δ(G)+3,2)-coloring,and every outer-1-planar graph G with maximum degree at least 8 or with girth at least 4 has an incidence(Δ(G)+2,2)-coloring.

关键词： incidence coloring outer--planar graph planar graph

Balancing act:The dilemma of rapid hyperglycemia correction in diabetes management

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World Journal of Diabetes 2024年第2期15卷 129-132页

作者： ke-xin Zhang Cheng-Xia Kan Xiao-Dong sun Department of Endocrinology and Metabolism Affiliated Hospital of Weifang Medical UniversityWeifang 261031Shandong ProvinceChina

The global diabetes surge poses a critical public health challenge,emphasizing the need for effective glycemic ***,rapid correction of chronic hyperglycemia can unexpectedly trigger microvascular complications,necessitating a reevaluation of the speed and intensity of glycemic *** suggest swift blood sugar reductions may cause inflammation,oxidative stress,and neurovascular changes,resulting in *** providers should cautiously approach aggressive glycemic control,especially in long-standing,poorly controlled *** and managing these complications requires a personalized,comprehensive approach with education,monitoring,and interdisciplinary *** management must balance short and longterm goals,prioritizing overall *** editorial underscores the need for a personalized,nuanced approach,focusing on equilibrium between glycemic control and avoiding overcorrection.

关键词： Diabetes Hyperglycemia correction Management Microvascular complications Glucose control