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Effect of thermal treatment on energy dissipation of granite under cyclic impact loading

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Transactions of Nonferrous Metals Society of China 2019年第2期29卷 385-396页

作者： Rong-hua SHU Tu-bing YIN Xi-bing li Zhi-qiang YIN li-zhong tang School of Resources and Safety Engineering Central South UniversityChangsha 410083China Key Laboratory of Deep Coal Mine Excavation Response and Disaster Prevention and Control Anhui University of Science and TechnologyHuainan 232001China

High temperature treatment causes thermal damage to rocks in deep *** study the thermal effect on the energy dissipation of rocks during the dynamic cyclic loading,cyclic impact loading experiments of heat-treated rocks were carried out using the splitting Hopkinson pressure bar(SHPB)experimental *** correlations among the energy dissipation,energy dissipation rate,impact times,accumulated absorbed energy per volume,failure mode and temperature were *** results show that the reflected energy under the first impact increases and finally exceeds the absorbed energy when the temperature increases;however,the total reflected energy decreases above 200℃.The absorbed energy under the first impact and the total absorbed energy all decrease as the temperature increases,the rates of which decrease *** the same phenomenon appears for the transmitted energy and the rate of the transmitted *** the contrary,the rate of the reflected energy increases with the rising *** the temperature increases,the fewer impact times are needed to destroy the *** addition,the failure modes are different when the rock is treated at different temperatures;that is,when the temperature is high,even though the absorbed energy is low,the sample breaks into powder after several impacts.

关键词： energy dissipation granite cyclic impact compression thermal treatment

Filter back-projection technique applied to Abel inversion

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Nuclear Science and Techniques 1997年第4期 22-25页

作者： Jiang Shao En, liu zhong li, tang Dao Yuan and Zheng Zhi Jian ( Southwest Institute of Nuclear Physics and Chemistry, Chengdu 610003 )

ＦｉｌｔｅｒｂａｃｋｐｒｏｊｅｃｔｉｏｎｔｅｃｈｎｉｑｕｅａｐｐｌｉｅｄｔｏＡｂｅｌｉｎｖｅｒｓｉｏｎＴｈｅＰｒｏｊｅｃｔＳｕｐｐｏｒｔｅｄｂｙＮａｔｉｏｎａｌＨｉｇｈＴｅｃｈｎｏｌｏｇｙ８３６Ｐｌａｎ４１６Ｓ... 详细信息

ＦｉｌｔｅｒｂａｃｋｐｒｏｊｅｃｔｉｏｎｔｅｃｈｎｉｑｕｅａｐｐｌｉｅｄｔｏＡｂｅｌｉｎｖｅｒｓｉｏｎＴｈｅＰｒｏｊｅｃｔＳｕｐｐｏｒｔｅｄｂｙＮａｔｉｏｎａｌＨｉｇｈＴｅｃｈｎｏｌｏｇｙ８３６Ｐｌａｎ４１６ＳｐｅｃｉａｌＳｕｂｊｅｃｔａｎｄＳ...

关键词： Filter function Back projection Abel transform

Characteristics of C and N Accumulation in Infertile Red Soil Under Different Rotation Systems

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Agricultural Sciences in China 2002年第10期1卷 1125-1132页

作者： li zhong-pei, tang Yong-liang, SHI Hua and ZHANG Tao-lin(Institute of Soil Science , Chinese Academy of Sciences , Nanjing 210008 , P. R . China ) Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 P.R.China

A long-term experiment was conducted at the Ecological Experimental Station of Red Soil, Chinese Academy of Sciences to investigate the characteristics of material cycling and C, N accumulation in infertile red soil under different treatments of rotation systems for 11 years. Plant biomass, amount of organic materials returned to the soil, and budget of nitrogen in soil were obviously different under conventional cultivation, coverage by shrubs (Lespedeza formosa), rotation of shrubs (Lespedeza formosa) and crops (Peanut-Buckwheat) . Rotation of shrubs and crops with a combination of rational fertilization would be 75 - 100% of biomass and a similar amount of organic materials returned to the soil compared with that under coverage shrubs, more input than output of nitrogen, high system stability, and increasing crop productivity. With distinct cycling, different treatments of rotation systems influenced discriminatorily soil fertility. Soil organic carbon and nitrogen were respectively less than 7 and 0.6 g kg-1 for conventional cultivation, 9-11 and 0.6-0.9 g kg-1 for rotation of shrubs and crops, 14 - 16 g kg-1 and more than 1 g kg-1 for coverage by shrubs after 11 years, which represent low, middle and high levels of upland red soil fertility at the current situation. It implied that with cultivation system and fertilization measures, the infertile red soil could have middle to high fertility after about 10 years rational utilization. Comparison of results from different treatments showed that a large loss of organic carbon and nitrogen was caused by soil erosion which resulted in a low level of C and N in upland red soil. It could be suggested that increasing carbon storage in infertile red soil would sequester a great amount of atmospheric CO2 and mitigate the global warming potentially.

关键词： Different rotation systems Infertile red soil C and N accumulation

有氧运动对Ⅱ型糖尿病大鼠腹主动脉Apelin和一氧化氮合酶/一氧化氮系统的影响

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西安体育学院学报 2015年第6期32卷 733-738页

作者：李忠堂阎智力华东师范大学上海200241 牡丹江师范学院体育科学学院黑龙江牡丹江157012

目的研究有氧运动对Ⅱ型糖尿病大鼠腹主动脉Apelin和一氧化氮合酶/一氧化氮(NOS/NO)系统的影响。方法雄性SD大鼠60只,随机抽取20只大鼠并分为正常对照组(C组)和正常运动组(Y组)。其余大鼠喂以高脂高糖饮食并腹腔小剂量注射链尿佐菌素的... 详细信息

目的研究有氧运动对Ⅱ型糖尿病大鼠腹主动脉Apelin和一氧化氮合酶/一氧化氮(NOS/NO)系统的影响。方法雄性SD大鼠60只,随机抽取20只大鼠并分为正常对照组(C组)和正常运动组(Y组)。其余大鼠喂以高脂高糖饮食并腹腔小剂量注射链尿佐菌素的方法建立Ⅱ型糖尿病模型。建模后,随机抽取20只大鼠随机分为糖尿病对照组(DM组,n=10)和糖尿病运动锻炼组(DME组,n=10)。Y组和DME组大鼠进行无负重游泳运动(60 min/次,6次/周×6周),6周后检测空腹血糖、血清胰岛素、NO浓度、腹主动脉Apelin含量及NOS活性等指标;利用RT-PCR法检测腹主动脉中NO、Apelin、t NOS、e NOS和i NOS的mRNA表达。结果 (1)与C组相比,DM组大鼠空腹血糖水平(Plin含量(Plin(Plin(Plin(Plin含量显著增多,出现"Apelin抵抗"。有氧运动锻炼可以显著改善Ⅱ型糖尿病大鼠腹主动脉生成NO的功能,降低Apelin含量,增强了Apelin/NOS/NO的舒血管效应。

关键词： Ⅱ型糖尿病有氧运动腹主动脉 Apelin 一氧化氮合酶/一氧化氮系统

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预测越野滑雪运动成绩生理学指标的实验研究

中国体育科技 2015年第3期51卷 88-93页

作者：李忠堂阎智力华东师范大学上海200024 牡丹江师范学院体育科学学院黑龙江牡丹江157012

采用文献资料调研、实验和数理分析等方法,通过跑台运动实验对反映越野滑雪运动成绩的生理学指标进行了研究,目的是探究跑台运动实验所测指标能否用于预测越野滑雪的比赛成绩,并试图筛选出能够更好地预测越野滑雪比赛成绩的生理指标。... 详细信息

采用文献资料调研、实验和数理分析等方法,通过跑台运动实验对反映越野滑雪运动成绩的生理学指标进行了研究,目的是探究跑台运动实验所测指标能否用于预测越野滑雪的比赛成绩,并试图筛选出能够更好地预测越野滑雪比赛成绩的生理指标。运用气体代谢测试法分别对无氧阈(AT)、矢代偿性代谢性酸中毒阈值(TDMA)、呼吸商(RQ)=1时运动强度和最大耗氧量(VO2max)进行了测量与计算,同时还测量了乳酸堆积拐点(OBLA)、最大心率百分比、VO2max百分比和不同单位下的耗氧量(VO2ml·kg-1·min-1、VO2ml·min-1·kg-2/3、VO2l·min-1)等参数指标,并利用皮尔逊相关系数和斯皮尔曼等级相关系数对数据进行了相关性分析。结果:OBLA指标与男子比赛成绩高度相关,RQ=1能更好地反映女子比赛成绩。关于VO2的测量,男子运动员最好运用l·min-1单位来预测比赛成绩,女子运动员可以运用l·min-1、ml·min-1·kg-2/3或ml·kg-1·min-1任何一种单位。研究结论:跑台运动实验所测的生理学指标可以应用于预测越野滑雪比赛成绩,且对于男、女运动员越野滑雪比赛成绩预测应该采用多种不同的参数指标来共同反映。

关键词：越野滑雪预测跑台实验 TDMA OBLA 无氧阈

Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 504-514页

作者： Lou Zhang Shuo li Fu tang Jingkai Zhang Yuetong Kang Hean Zhang lidong li State Key Laboratory for Advanced Metals and Materials School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial ***,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water *** this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing *** analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag *** surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their *** the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite *** inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag *** prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.

关键词： silver nanoparticles hydrogel straw extraction antibacterial

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我国基础教育体育课程改革60年回顾

体育学刊 2010年第12期17卷 52-56页

作者：李忠堂阎智力牡丹江师范学院体育科学学院黑龙江牡丹江157012 华东师范大学体育与健康学院上海200241

对我国基础教育体育课程改革60年历程的回顾,明确了在课程理念、课程内容、教学方法和课程评价等方面所取得的巨大成绩;教学思想转变为"以人为本、健康第一",更加强调"三维健康观";同时指出在新的基础教育体育课程改革中存在体育课程目... 详细信息

对我国基础教育体育课程改革60年历程的回顾,明确了在课程理念、课程内容、教学方法和课程评价等方面所取得的巨大成绩;教学思想转变为"以人为本、健康第一",更加强调"三维健康观";同时指出在新的基础教育体育课程改革中存在体育课程目标泛化与均衡化、体育课程内容设置与开发原则不明确、弱化了传统接受式教学方法在体育教学中的地位等问题。提出应进一步统一思想,认真对新体育课程标准进行解读;加快高校师资培养与中小学体育教学的接轨;并对新课程标准实施中存在的问题进行必要的修正和补充。

关键词：学校体育基础教育体育课程改革中国

跑台运动对肥胖大鼠脂肪组织MSTN和ActRⅡB基因表达的影响

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北京体育大学学报 2015年第5期38卷 52-56页

作者：李忠堂阎智力牡丹江师范学院体育科学学院黑龙江牡丹江157012 华东师范大学体育与健康学院上海200241

目的:观察跑台运动对高脂膳食诱导肥胖大鼠白色脂肪组织(WAT)和棕色脂肪组织(BAT)内肌肉合成抑制因子(myostatin,MSTN)信号通路的影响。方法:60只健康雄性Wistar大鼠随机分为对照组和高脂膳食组,分别喂养普通饲料和高脂饲料,8周后分别筛... 详细信息

目的:观察跑台运动对高脂膳食诱导肥胖大鼠白色脂肪组织(WAT)和棕色脂肪组织(BAT)内肌肉合成抑制因子(myostatin,MSTN)信号通路的影响。方法:60只健康雄性Wistar大鼠随机分为对照组和高脂膳食组,分别喂养普通饲料和高脂饲料,8周后分别筛选16只普通大鼠和16只肥胖大鼠,随机分为安静对照组(SC,n=8)、运动对照组(EC,n=8)、安静肥胖组(SO,n=8)和运动肥胖组(EO,n=8)。EC和EO组以21 m/min的速度进行跑台训练,同时SC和SO组置于静止跑台,自由活动,每次1 h,每周5次,持续8周。测定大鼠体重、血清内甘油三酯(TG)、胆固醇(TC)、高密度脂蛋白(HDL)、低密度脂蛋白(LDL)水平,分离大鼠肾周脂肪和睾周脂肪作为WAT,肩胛区脂肪作为BAT,称重。采用RT-PCR分别检测WAT和BAT内MSTN和ActRⅡB的mRNA水平。结果:1)与SC组比较,EC组体重显著降低(P<0.05),BAT质量极显著增加(P<0.01),HDL水平显著增加(P<0.05);SO组体重、WAT、TC水平极显著增加(P<0.01),TG、LDL水平显著性增加(P<0.05),HDL水平显著性降低(P<0.05);与SO组比较,EO组体重、WAT、TG水平显著降低(P<0.05)。2)在WAT内,与SC组比较,EC组ActRⅡB极显著性降低(P<0.01),SO组MSTN极显著性增加(P<0.01);与SO组比较,EO组MSTN、ActRⅡB表达极显著性降低(P<0.01)。在BAT内,与SC组比较,EC组MSTN极显著性增加(P<0.01),而ActRⅡB极显著性降低(P<0.01),同时SO组ActRⅡB也极显著性降低(P<0.01);与SO组比较,EO组MSTN、ActRⅡB极显著性增加(P<0.01)。结论:8周跑台运动可能通过MSTN信号通路调节高脂膳食诱导肥胖大鼠WAT和BAT质量变化。

关键词：跑台运动肥胖白色脂肪组织棕色脂肪组织肌肉合成抑制因子信号通路

Cell polarization in ischemic stroke: molecular mechanisms and advances

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Neural Regeneration Research 2025年第3期20卷 632-645页

作者： Yuanwei li Xiaoxiao Xu Xuan Wu Jiarui li Shiling Chen Danyang Chen Gaigai li Zhouping tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

关键词： astrocyte polarization immune regulation inflammation ischemic injury microglia polarization neutrophil polarization signaling pathways stroke