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煤块冲击破碎速度研究

振动与冲击 2011年第3期30卷 18-21页

作者：刘瑜杜长龙付林高魁东中国矿业大学机电工程学院徐州221116

冲击破碎速度是影响煤块冲击破碎效果的主要参数。基于分段塑变碰撞模型得到煤块与冲击板碰撞时的接触应力,并结合裂缝假说和能量守恒原理推导出煤块被破碎到指定粒度需要的理论冲击速度。进行煤块冲击破碎试验,通过试验数据分析得到了... 详细信息

冲击破碎速度是影响煤块冲击破碎效果的主要参数。基于分段塑变碰撞模型得到煤块与冲击板碰撞时的接触应力,并结合裂缝假说和能量守恒原理推导出煤块被破碎到指定粒度需要的理论冲击速度。进行煤块冲击破碎试验,通过试验数据分析得到了冲击破碎速度的试验拟合公式和理论修正公式。88%的拟合计算值与试验值的误差小于10%,但拟合公式结构复杂,不适合工程应用;85%的理论修正值与试验值的误差小于20%,满足初级破碎所需的精度,可以作为初级破碎时冲击破碎速度的理论选择依据。

关键词：煤块冲击破碎速度裂缝假说试验修正

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

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Neural Regeneration Research 2025年第5期20卷 1416-1430页

作者： Mou gao Qin dong Dan Zou Zhijun Yang Lili Guo Ruxiang Xu Department of Neurosurgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Neurosurgery Chinese PLA General HospitalBeijingChina Department of Neurology Fu Xing HospitalCapital Medical UniversityBeijingChina

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and *** previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological ***,the mechanism of CXCR4 upregulation in induced neural stem cells remains *** this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 ***,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial *** agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury ***,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head *** conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neura

关键词： Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell microglia neuroinflammation

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肋板形镐形截齿的优势分析

煤矿机械 2010年第1期31卷 88-89页

作者：高魁东杜长龙许瑞中国矿业大学机电工程学院江苏徐州221116

肋板形镐形截齿是普通镐形截齿在形式上的改变,通过对普通镐形截齿和肋板形镐型截齿的静力分析,证明了肋板形镐形截齿的可行性;并通过理论分析,说明了肋板型镐形截齿相对于普通镐形截齿具有的优势。

关键词：肋板形镐形截齿抗弯强度耐磨性

Small extracellular vesicles derived from human induced pluripotent stem cell-differentiated neural progenitor cells mitigate retinal ganglion cell degeneration in a mouse model of optic nerve injury

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Neural Regeneration Research 2025年第2期20卷 587-597页

作者： Tong Li Hui-Min Xing Hai-dong Qian Qiao gao Sheng-Lan Xu Hua Ma Zai-Long Chi State Key Laboratory of Ophthalmology Optometry and Visual ScienceEye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina

Several studies have found that transplantation of neural progenitor cells(NPCs)promotes the survival of injured ***,a poor integration rate and high risk of tumorigenicity after cell transplantation limits their clinical *** extracellular vesicles(sEVs)contain bioactive molecules for neuronal protection and *** studies have shown that stem/progenitor cell-derived sEVs can promote neuronal survival and recovery of neurological function in neurodegenerative eye diseases and other eye *** this study,we intravitreally transplanted sEVs derived from human induced pluripotent stem cells(hiPSCs)and hiPSCs-differentiated NPCs(hiPSC-NPC)in a mouse model of optic nerve *** results show that these intravitreally injected sEVs were ingested by retinal cells,especially those localized in the ganglion cell *** with hiPSC-NPC-derived sEVs mitigated optic nerve crush-induced retinal ganglion cell degeneration,and regulated the retinal microenvironment by inhibiting excessive activation of *** analysis further revealed that hiPSC-NPC derived sEVs transported neuroprotective and anti-inflammatory miRNA cargos to target cells,which had protective effects on RGCs after optic nerve *** findings suggest that sEVs derived from hiPSC-NPC are a promising cell-free therapeutic strategy for optic neuropathy.

关键词： exosome miRNA neural progenitor cell neurodegeneration neuroinflammation neuroprotection optic nerve crush optic neuropathy retinal ganglion cell small extracellular vesicles

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镐齿安装角和半锥角随截深变化规律研究

煤炭科学技术 2011年第1期39卷 93-96页

作者：高魁东杜长龙刘送永付林中国矿业大学机电工程学院江苏徐州221116

针对目前采煤机滚筒叶片上采用同一型号截齿、相同安装角布置导致的不同截深处截齿受力不同的问题,参照Evans.I镐型截齿破煤模型的建立过程,结合煤岩开采的实际情况,在综合考虑煤岩压酥效应、煤壁倾角及截齿安装角的基础上,通过对破煤... 详细信息

针对目前采煤机滚筒叶片上采用同一型号截齿、相同安装角布置导致的不同截深处截齿受力不同的问题,参照Evans.I镐型截齿破煤模型的建立过程,结合煤岩开采的实际情况,在综合考虑煤岩压酥效应、煤壁倾角及截齿安装角的基础上,通过对破煤过程的力学分析建立了数学模型,并对该模型进行仿真研究。仿真结果表明:截深在0～1.1 m,半锥角随截深增加呈线性减小趋势,安装角呈非线性减小趋势,其变化范围、变化趋势与煤层的地质条件有一定关系。该研究对不同截深处截齿的安装布置提供了理论依据。

关键词：镐型截齿安装角半锥角破煤模型压酥效应

Bulging Performance and Quality Control of Aluminum Alloy Tailor-welded Overlapping Sheets Based on Interface Friction

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 258-264页

作者： gao Tiejun gao Bowen LI Weijie ZHANG Jiabin College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China Shenyang Aerospace Xinguang Group Co.L td. Shenyang 110043China

In order to solve the problem of poor formability caused by different materials and properties in the process of tailor-welded sheets forming,a forming method was proposed to change the stress state of tailor-welded sheets by covering the tailor-welded sheets with better plastic properties overlapping *** the same time,the interface friction effect between the overlapping and tailor-welded sheets was utilized to control the stress magnitude and further improve the formability and quality of the tailor-welded *** this work,the bulging process of the tailor-welded overlapping sheets was taken as the research *** alloy tailor-welded overlapping sheets bulging specimens were studied by a combination of finite element analysis and experimental *** results show that the appropriate use of interface friction between tailor-welded and overlapping sheets can improve the formability of tailor-welded sheets and control the flow of weld seam to improve the forming *** increasing the interface friction coefficient on the side of tailor-welded sheets with higher strength and decreasing that on the side of tailor-welded sheets with lower strength,the deformation of the tailor-welded sheets are more uniform,the offset of the weld seam is minimal,the limit bulging height is maximal,and the forming quality is optimal.

关键词： tailor-welded sheets overlapping sheet bulging interface friction weld seam stress

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空分装置内外压缩流程热力计算对比

化肥设计 2005年第4期43卷 18-19页

作者：谢春晖高东奎山东华鲁恒升化工股份有限公司山东德州253000

对40000m3/h空分装置内、外压缩流程进行了热力计算,对比了外压式、半内压式、全内压式流程所需功耗的高低,分析了产品能耗指标的影响因素,根据不同装置的实际情况,对压缩流程进行了优化选择。

关键词：空分装置外压缩内压缩半内压缩总能耗:对比

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai Li Zhen Ma Jin-Hua gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

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青岛海域小眼绿鳍鱼耳石形态的初步研究

中国海洋大学学报（自然科学版） 2009年第4期39卷 622-626页

作者：张晓霞叶振江王英俊高东奎杨永桓中国海洋大学水产学院山东青岛266003 广西北海市渔政管理站广西北海536000

利用2002年6-12月期间采自青岛海域商业渔获的286尾小眼绿鳍鱼（Chelidonichthys spinosus）标本,以耳石长、耳石宽、周长、面积、矩形趋近率、充实度为基本形态学参数,结合其中傅里叶变换获得的形态特征变量,研究了小眼绿鳍鱼幼鱼生长... 详细信息

利用2002年6-12月期间采自青岛海域商业渔获的286尾小眼绿鳍鱼（Chelidonichthys spinosus）标本,以耳石长、耳石宽、周长、面积、矩形趋近率、充实度为基本形态学参数,结合其中傅里叶变换获得的形态特征变量,研究了小眼绿鳍鱼幼鱼生长过程耳石形态的逐月变化特征。结果显示,小眼绿鳍鱼耳石为不规则卵圆形或近四边形,背部弧状隆起,腹部相对略平,前部有一明显缺刻,后部常呈锯齿状尖突。小眼绿鳍鱼耳石长、耳石重、耳石面积皆与体长呈显著相关,耳石长宽比与体长不呈显著相关。随着小眼绿鳍鱼生长,该鱼耳石形态特征随月份变化差异显著;经多因子方差分析和判别分析表明,研究期间小眼绿鳍鱼耳石形态可分为3个特征区间：6月份与其他月份间形态差异显著;7-9月耳石形态特征处于变化间状态;10-12月各方面形态特征趋于稳定。

关键词：小眼绿鳍鱼耳石形态与发育 Fourier系数