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Mechanical mechanism and support design analysis on bolt-beam-net support in soft rock roadway in Qigou Coal Mine

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Journal of Coal Science & Engineering(China) 2012年第3期18卷 247-253页

作者： LI Tao SHAN Ren-liang HAN Huan-shang yang wei-hong LIU Nian School of Mechanics&Civil Engineering China University of Mining&Technology(Beijing)Beijing 100083China Datong Coal Mine Group Datong 037003China

The deformation and failure mechanical mechanism in soft rock roadway is related to the stability of supported tunnels, which is important to coal mine production and construction. By physical mechanics experiments and X-ray diffraction （XRD） tests, the engineering mechanical properties of soft rock, as well as main mineral composition of the surrounding soft rock of Qigou Coal Mine, were obtained. Based on analysis results, a method using bolt-beam-net combination to support was put forward. Mechanical analysis of the support form was done by using the calculation software FLAC3D. Results show that clay minerals of this mine are kaolinite and illite mixed layer, of which the water absorption is relatively obvious and presented mudding characteristic after absorbing water, with the plasticity index of 0.35, with small expansibility, which is weakly consolidated colloid with strong connected force in unit cell. The rock blocks have the characteristics of moisture absorption softening, and the deformation mechanical mechanism of which is with the coexistence of molecular expansive mechanism, colloid expansive mechanism, and weak layer trend type. The calculation results show that the bolt-beam-net support structure makes the bolt, beam, and roof deform compatibly. The beams make the force in the bolt relatively homogeneous, which restricts the displacement of the tunnel roof as well. Finally, using in situ monitoring, the numerical results were verified.

关键词： soft rock roadway mechanical mechanism combined supporting support design in situ monitoring

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柱等离子体中磁流体力学波之间的耦合

核聚变与等离子体物理 2001年第1期21卷 1-6页

作者：杨维纮中国科学技术大学近代物理系合肥230027

采用柱螺旋坐标系 ,把广义磁流体力学方程组简化为四元一阶微分方程组。在ω/ωci→ 0时 ,该方程组化为Hain L櫣ｓｔ方程 ;而当p→ 0 时 ,即是KAppert理论。在这两种情况下 ,Alfv啨ｎ波共振层都是奇异的。Alfv啨ｎ波共振层的奇异性来源... 详细信息

采用柱螺旋坐标系 ,把广义磁流体力学方程组简化为四元一阶微分方程组。在ω/ωci→ 0时 ,该方程组化为Hain L櫣ｓｔ方程 ;而当p→ 0 时 ,即是KAppert理论。在这两种情况下 ,Alfv啨ｎ波共振层都是奇异的。Alfv啨ｎ波共振层的奇异性来源于极限的选取谠独爰薜那?,离子的惯性会使理想磁流体中Alfv啨ｎ波共振层的奇异性消失。

关键词：磁流体理论托卡马克耦合柱等离子体 Alfveen波共振层柱螺旋坐标系奇异性极限磁流体力学波 Hain-Luest方程 Appert理论

Cytophagic Histiocytic Panniculitis with Encephaloclastic Changes:A Case Report and Literature Review

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Chinese Journal of Clinical Oncology 2006年第3期3卷 223-226页

作者： Aijun Liao Huihan Wang Zhuogang Liu Xiaobin Wang wei yang hong Shu Department of Hematology the Second Affiliated Hospital China Medical University Shenyang 110004 China.

Cytophagic histiocytic panniculitis （CHP） was first described by Winkelmann and Bowie in *** It is a rare group of diverse illnesses involving benign and malignant proliferation of macrophages in various organs and tissues. It presents with subcutaneous panniculitis with or without a hemophagocytic syndrome （HPS）. It occurs predominantly in women （male： female ratio 1：1.3） between the years of 5-61 （average, 33.5）. The major clinical features are recurrent fever, multiple panniculitic lesions, anemia, leukopenia and coagulation abnormalities. In the later phase, liver dysfuction, serosal effusion, mucosal ulceration and hemorrhage may occur. Histological findings show activated histiocyte infiltration of the fat tissue. Cytologically the benign-looking histiocytes containing cell fragments （bean-bag cells） are very typical. CHP has a broad spectrum from mild to severe. Benign CHP is selflimiting and sensitive to treatment, but up to now there is no effective therapy for malignant CHP. We report here a case of progressive and fatal cytophagic histiocytic panniculitis in a young woman who had encephaloclastic changes immediately prior to her death.

关键词： cytophagic histiocytic panniculitis encephaloclastic subcutaneous panniculitic T-cell lymphoma.

辽南地块新太古代2.52～2.46Ga构造-热事件的识别及地质意义

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岩石学报 2017年第9期33卷 2775-2784页

作者：王伟杨红冀磊中国地质科学院地质研究所 100037

胶-辽-吉活动/造山带是华北克拉通早前寒武纪基底三条古元古代构造带之一,对其邻区内太古宙地质体的岩石组合和时空分布的研究,可为制约胶-辽-吉带的构造属性以及华北克拉通东部在古元古代时期的构造格局提供重要依据。胶-辽-吉带的北... 详细信息

胶-辽-吉活动/造山带是华北克拉通早前寒武纪基底三条古元古代构造带之一,对其邻区内太古宙地质体的岩石组合和时空分布的研究,可为制约胶-辽-吉带的构造属性以及华北克拉通东部在古元古代时期的构造格局提供重要依据。胶-辽-吉带的北侧为龙岗地块,南侧为辽南和狼林地块,本文对辽南地块中典型前寒武纪基底变质岩石进行了详细的野外地质、岩石学和锆石LA-ICP-MS U-Pb年代学研究,结果显示原岩为石英闪长岩或英云闪长岩的黑云角闪片麻岩(DL05-1)和侵入其中的花岗质脉体(DL05-2)分别形成于2523±11Ma(MSWD=0.62)和2505±13Ma(MSWD=0.67),原岩为TTG岩系的黑云斜长片麻岩(DL10-1)形成于2521±12Ma(MSWD=1.15)。2件斜长角闪岩样品(DL12-1和DL07-1)分别给出2521±16Ma(MSWD=1.9)和2464±20Ma(MSWD=0.72)的^(207)Pb/^(206)Pb加权平均年龄,前者的锆石形态、结构和Th-U体系组成具有高温岩浆成因的特征,因此2521±16Ma代表基性原岩的形成时代,后者的锆石没有明显的内部结构,且Th、U含量低(分别为6×10^(-6)~29×10^(-6)、9×10^(-6)~26×10^(-6))具变质重结晶锆石的特征,2464±20Ma代表区域变质事件的年龄。侵入斜长角闪岩的2件花岗片麻岩样品(DL12-2和DL07-2)207Pb/206Pb加权平均年龄分别为2498±18Ma(MSWD=1.4)和2.1Ga,1件钾质花岗岩样品(DL17-1)由于强烈的Pb丢失未能获得准确的形成年龄,根据野外产状和锆石U-Th-Pb组成推测该钾质花岗岩形成于新太古代晚期。虽然辽南地块内太古宙表壳岩的时空分布规律目前还不清楚,但本文的研究结果进一步确认,辽南地块内存在新太古代2.52Ga基性岩、闪长岩和TTG组合,它们的形成时代总体上不晚于共生的花岗岩(2.50Ga),而后辽南地块经历了新太古代晚期2.46Ga区域变质作用的改造。侵位时代接近2.1Ga花岗岩的存在表明辽南地块太古宙陆壳在形成后受到2.1Ga构造-热事件的影响。另一方面,本文研究的花岗质岩石样品中残余锆石核年龄分布于2.61~2.51Ga,表明辽南地块内古老大陆地壳物质的形成时代至少可以追溯至新太古代早期。辽南地块内太古宙岩浆、变质作用时限和陆壳物质的形成时间都与华北克拉通东部可以对比,具有华北的太古宙基底属性。与狼林地块相比,辽南地块内太古宙的岩石类型更加丰富,规模也更大;与胶-辽-吉活动/造山带北侧龙岗地块相比,辽南地块内尚没有发现大规模条带状铁建造(BIF)和形成于新太古代之前(>2.8Ga)的岩石,且变质程度相对较低。目前的地质和年代学证据尚不支持辽南地块与胶-辽-吉带北侧的龙岗地块原属于同一陆壳基底。

关键词：辽南地块太古宙 LA-ICP-MS 构造-热事件华北克拉通

Genome-Wide Analysis Regulatory Network of Photomorphogenesis Revealed the Complex Brassinosteroid Effects in

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Molecular Plant 2009年第4期2卷 755-772页

作者： Li Song Xiao-Yi Zhou Li Li Liang-Jiao Xue Xi yang hong-wei Xue National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 300 Fenglin Road 200032 Shanghai China

Light and brassinosteroids （BRs） have been proved to be crucial in regulating plant growth and development; however, the mechanism of how they synergistically function is still largely unknown. To explore the underlying mechanisms in photomorphogenesis, genome-wide analyses were carried out through examining the gene expressions of the dark-grown WT or BR biosynthesis-defective mutant det2 seedlings in the presence of light stimuli or exogenous Brassinolide （BL）. Results showed that BR deficiency stimulates, while BL treatment suppresses, the expressions of lightresponsive genes and photomorphogenesis, confirming the negative effects of BR in photomorphogenesis. This is consistent with the specific effects of BR on the expression of genes involved in cell wall modification, cellular metabolism and energy utilization during dark-light transition. Further analysis revealed that hormone biosynthesis and signaling-related genes, especially those of auxin, were altered under BL treatment or light stimuli, indicating that BR may modulate photomorphogenesis through synergetic regulation with other hormones. Additionally, suppressed ubiquitin-cycle pathway during light-dark transition hinted the presence of a complicated network among light, hormone, and protein degradation. The study provides the direct evidence of BR effects in photomorphogenesis and identified the genes involved in BR and light signaling pathway, which will help to elucidate the molecular mechanism of plant photomorphogenesis.

关键词： brassinosteroid light photomorphogenesis hormone interplay ubiquitin.

环瓣式浮环密封表面瑞利台阶型槽气体润滑动压特性

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推进技术 2022年第2期43卷 142-148页

作者：仰宏伟白少先浙江工业大学机械工程学院浙江杭州310032

为提高密封气膜的开启能力以满足长寿命设计要求,基于气体润滑理论研究了环瓣式浮环密封表面瑞利台阶型槽的动压特性。采用有限差分方法,数值计算了密封气膜压力分布和动压效应,分析了操作参数和型槽几何参数对密封气膜压力和泄漏率的... 详细信息

为提高密封气膜的开启能力以满足长寿命设计要求,基于气体润滑理论研究了环瓣式浮环密封表面瑞利台阶型槽的动压特性。采用有限差分方法,数值计算了密封气膜压力分布和动压效应,分析了操作参数和型槽几何参数对密封气膜压力和泄漏率的影响规律。结果表明,表面瑞利台阶型槽可以产生明显的气体润滑动压效应,可使得密封气膜平均压力和泄漏率分别增加38.6%和10.3%;型槽几何参数对动压效应影响明显,槽宽、槽数和槽深的增加均可使气膜平均压力增加;随着槽宽和槽数半径比的增加,无量纲平均压力先增加后减小。

关键词：环瓣式浮环密封气体润滑瑞利台阶型槽动压特性型槽参数

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新建天津至潍坊铁路建设必要性研究

铁道工程学报 2018年第2期35卷 6-10页

作者：杨卫红中国铁路设计集团有限公司天津300142

研究目的:津潍铁路不仅是"八纵八横"高速铁路主通道之沿海和京沪通道的重要组成,也是京津冀及山东半岛城市群城际网的组成元素。本文从社会经济特征、交通运输结构、在路网中的功能和定位、运输需求预测、建设必要性等方面展开研究,为... 详细信息

研究目的:津潍铁路不仅是"八纵八横"高速铁路主通道之沿海和京沪通道的重要组成,也是京津冀及山东半岛城市群城际网的组成元素。本文从社会经济特征、交通运输结构、在路网中的功能和定位、运输需求预测、建设必要性等方面展开研究,为决策者提供依据,为项目投资者提供参考。研究结论:(1)本线可与京沪通道共同分担京津及以远与胶东半岛、鲁南、苏北、上海等地的交流,兼顾部分京津及以远与合肥及以远交流;(2)津潍铁路建设必要性体现在:一是支撑并引领国家三大战略的需要;二是推进铁路客运供给侧改革的需要;三是促进区域新型城镇化建设的需要;四是完善和优化京沪通道综合交通运输体系的需要;五是推进区域协调发展的需要;六是促进沿线旅游业发展的需要;(3)本研究成果可为类似铁路项目的规划提供参考。

关键词：新建铁路必要性

Reverse dedifferentiation of atrial cardiomyocytes after restoration of sinus rhythm from atrial fibrillation in goats

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Journal of Geriatric Cardiology 2009年第4期6卷 230-236页

作者： Feng-Xiang Zhang Ming-Long Chen Bing yang wei-Zhu Ju hong-Wu Chen Dong-Jie Xu Chun Chen Ke-Jiang Cao Cardiovascular Medical Center of Jiangsu Province First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China.

Objective Chronic atrial fibrillation （AF） results in dedifferentiation of atrial cardiomyocytes that plays an important role in the perpetuation of AF. In this study, we aimed to investigate the changes oftitin and a-smooth muscle actin （α-SMA） after long time of AF reversal. Methods Twenty-four goats were randomized into four groups：（1） sinus rhythm （SR）, （2） 3 months AF （3-too AF）, （3） 3 months SR after 3 months AF （3-mo post AF）, （4） 6 months SR after 3-mo AF （6-mo post AF）, with 6 in each group. By pacing on the anterior bottom of left atria appendage （LAA）, we established a goat model of chronic AF. Atria effective refractory period （AERP） was measured with electrophysiological methods. Ultra-structure was studied with echocardiography, light and electron microscopy. Titin and α-SMA protein expressions were determined by Western blot. Results The animals underwent high rate pacing on LAA for a mean of 42.23± 21.70 days before presenting AF. Electrophysiological analysis revealed that AERP completely resumed in 3-mo post AF goats. Echocardiography displayed that the size of left atrium resumed almost in 6-too post AF goats （P〈 0.01）. Pathological and electron microscopic examination revealed the disorder of myofibrils, augmentation of intercellular space, myolysis, accumulation of glycogen, and numerous bigger mitochondria among atrial cardiomyocytes in 3-mo AF goats. They recovered mostly in 6-mo post AF goats. Western blot showed that the band density oftitin significantly reduced in 3-mo AF goats compared to SR ones [1826 ± 319 vs 5012±854, P 〈 0.01]. In 3- and 6-mo post AF goats, titin increased gradually and it reversed completely in 6-mo post AF goats （3841 ± 601 and 4523 ±833 respectively, P 〈 0.01）. Conversely, the band density ofa-SMAwas significantly higher in 3-mo AF goats （5324 ± 948） than in SR ones （1619 ±271, P 〈 0.01）. In 3- and 6-mo post-AF goats, α-SMA decreased gradually, and it recovered mostly in 6- mo post AF goats （4437 ± 792 and 2205 ±

关键词： cardiology atrial fibrillation reverse remodeling dedifferentiation electrophysiological study

COX-2调节的前列腺素在突触信号传递中的作用

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生理科学进展 2009年第4期40卷 317-320页

作者：杨红卫三峡大学医学院生理学教研室湖北宜昌443002

环氧合酶-2(cyclooxygenase-2,COX-2)是催化花生四烯酸转化为前列腺素的限速酶,广泛参与脑创伤、缺血诱导的神经元损伤、炎症反应及神经变性性疾病等。COX-2在神经病理学中的作用与神经元的突触变化有关。增强或抑制COX-2表达可增强或... 详细信息

环氧合酶-2(cyclooxygenase-2,COX-2)是催化花生四烯酸转化为前列腺素的限速酶,广泛参与脑创伤、缺血诱导的神经元损伤、炎症反应及神经变性性疾病等。COX-2在神经病理学中的作用与神经元的突触变化有关。增强或抑制COX-2表达可增强或抑制兴奋性谷氨酸能神经元的神经传递和长时程增强(LTP),这些效应由COX-2的主要产物前列腺素E2(PGE2)及其受体亚型EP2所介导。因此,阐明COX-2在突触信号中的作用机制将有助于设计新的药物来预防、治疗及减轻神经源性炎症相关的神经紊乱性疾病。

关键词：环氧合酶-2 前列腺素E2 炎症突触可塑性