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针对地下室场景4.8 GHz频段传播特性研究

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现代电子技术 2024年第5期47卷 23-28页

作者：孙磊丁茂尹以雁幸锋李治文张婧张静怡蒋金鸿中国移动通信集团云南有限公司云南昆明650228 南京邮电大学电子与光学工程学院、柔性电子(未来技术)学院江苏南京210003

地下室无线网络信号覆盖一直都是关系到人们感知通信的重要民生事件,但由于其空间封闭,使得室外信号难以穿透,严重影响了运营商的服务质量。文中基于入射及反弹射线法/镜像法对典型地下室环境进行建模仿真;研究了4.8 GHz频段下有车体存... 详细信息

地下室无线网络信号覆盖一直都是关系到人们感知通信的重要民生事件,但由于其空间封闭,使得室外信号难以穿透,严重影响了运营商的服务质量。文中基于入射及反弹射线法/镜像法对典型地下室环境进行建模仿真;研究了4.8 GHz频段下有车体存在和无车体存在时的电波传播特性并对数据进行处理;计算出不同距离的发射机与接收机对应的接收功率和路径损耗,并与1.9 GHz频段相应参数进行了对比,为优化网络覆盖提供了理论依据。通过研究表明,有车体存在时接收功率更大一些,5G频段相比4G频段接收功率更小一些。

关键词：地下室接收功率路径损耗网络覆盖 4G 5G 不同频段

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抽油机井恒功率变频控制系统研究

石油机械 2024年第2期52卷 99-106页

作者：王青华邹洪岚晏军江劲宏刘永辉王其军罗程程中国石油勘探开发研究院西南石油大学油气藏地质及开发工程国家重点实验室

抽油机作为陆上油田最重要的机械采油装备之一,近年来已发展出一系列的变频节能技术,但其研究主要集中在硬件方面,缺乏相关基础理论,导致现场应用普适性差,应用效果参差不齐。为此,研究有杆泵变频测控机理,优选了主要部件,对测试数据提... 详细信息

抽油机作为陆上油田最重要的机械采油装备之一,近年来已发展出一系列的变频节能技术,但其研究主要集中在硬件方面,缺乏相关基础理论,导致现场应用普适性差,应用效果参差不齐。为此,研究有杆泵变频测控机理,优选了主要部件,对测试数据提出了要求,形成了有杆泵抽油变频控制系统。构建BP神经网络系统对正常井和漏失、柱塞碰泵、气体影响等异常井进行识别,分类提出变频计算模型:考虑负扭矩和抽油机冲次界限等建立了正常井恒功率变频计算模型,实例对比分析了变频后抽油机速度、加速度变化规律,产液量一定时,负功功率和有功功率分别下降了65%和44%。建立了上行程漏失的异常井变频计算模型,针对性地提高上行程冲次,形成“上快下慢”运行模式。实例计算表明:该系统缩短上行程时间2.6 s,较好地解决有杆泵上行程漏失和变频节能的问题。研究成果可为抽油机变频技术提供理论支持,对油田节能和提产具有指导意义。

关键词：有杆抽油系统变频控制 BP神经网络恒功率数学模型

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Synthesis of spherical nano-ZSM-5 zeolite with intergranular mesoporous for alkylation of ethylbenzene with ethanol to produce m-diethylbenzene

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Chinese Journal of Chemical Engineering 2024年第3期67卷 298-309页

作者： Siyue Wang jinhong Li Qingxin Xu Shengjie Song Yu'ni jiang Lidong Chen Xin Shi Weiguo Cheng Faculty of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 110629China Beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to develop efficient and stable heterogeneous ***,the spherical nano-ZSM-5 zeolite with abundant intergranular mesoporous is synthesized by the seed-mediated growth method for alkylation of EB with ethanol to produce *** results show that the spherical nano-ZSM-5 zeolite exhibits better stability and higher alkylation activity at a lower temperature than those of commercial micropore *** then,the spherical nano-ZSM-5 is further modified by La_(2)O_(3) through acid treatment followed by immersion *** acid treatment causes nano-ZSM-5 to exhibit the increased pore size but decreased the acid sites,and subsequent La_(2)O_(3) loading reintroduces the weak acid *** a result,the HNO_(3)-La_(2)O_(3)-modified catalyst exhibits a slight increase in EB conversion and DEB yield in comparison with unmodified one,and meanwhile,it still maintains high m-DEB *** catalyst after acid treatment achieves higher catalytic stability besides maintaining the high alkylation activity of EB with *** present study on the spherical nano-HZSM-5 zeolite and its modification catalyst with excellent alkylation ability provides new insights into the production of mDEB.

关键词： Zeolite Modification Alkylation reaction m-diethylbenzene Catalyst Fixed-bed

NLRP3 inflammasome activation determines the fibrogenic potential of PM_(2.5) air pollution particles in the lung

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Journal of Environmental Sciences 2022年第1期34卷 429-441页

作者： Wei Cao Xiang Wang Jiulong Li Ming Yan Chong Hyun Chang Joshua Kim jinhong jiang Yu-Pei Liao Shannon Tseng Sydney Kusumoputro Candice Lau Marissa Huang Pengli Han Pengju Lu Tian Xia Translational Medical Center Zhengzhou Central Hospital Affiliated Zhengzhou UniversityZhengzhou 450007China Division of NanoMedicine Department of MedicineUniversity of CaliforniaLos Angeles 90095CAUnited States Basic Medical College Zhengzhou UniversityZhengzhou 450001China Department of Ecology and Evolutionary Biology University of CaliforniaLos Angeles 90095CAUnited States Department of Integrative Biology and Physiology University of CaliforniaLos Angeles 90095CAUnited States Department of Molecular Cell and Developmental BiologyUniversity of CaliforniaLos Angeles 90095CAUnited States

Airborne fine particulate matter(PM_(2.5))is known to cause respiratory inflammation such as chronic obstructive pulmonary disease and lung ***3 inflammasome activation has been implicated in these diseases;however,due to the complexity in PM_(2.5)compositions,it is difficult to differentiate the roles of the components in triggering this *** collected eight real-life PM_(2.5)samples for a comparative analysis of their effects on NLRP3 inflammasome activation and lung *** vitro assays showed that although the PM_(2.5)particles did not induce significant cytotoxicity at the dose range of 12.5to 100μg/m L,they induced potent TNF-αand IL-1βproduction in PMA differentiated THP-1 human macrophages and TGF-β1 production in BEAS-2B human bronchial epithelial *** the dose of 100μg/m L,PM_(2.5)induced NLRP3 inflammasome activation by inducing lysosomal damage and cathepsin B release,leading to IL-1β*** was confirmed by using NLRP3-and ASC-deficient cells as well as a cathepsin B inhibitor,ca-074 *** of PM_(2.5)via oropharyngeal aspiration at 2 mg/kg induced significant TGF-β1 production in the bronchoalveolar lavage fluid and collagen deposition in the lung at 21days post-exposure,suggesting PM_(2.5)has the potential to induce pulmonary *** ranking of in vitro IL-1βproduction correlates well with the in vivo total cell count,TGF-β1 production,and collagen *** summary,we demonstrate that the PM_(2.5)is capable of inducing NLRP3 inflammasome activation,which triggers a series of cellular responses in the lung to induce fibrosis.

关键词： Particulate matter Predictive toxicology NLRP3 inflammasome IL-1β Lung fibrosis Lung inflammation

Petrogenesis and Tectonic Implications of the Paleoproterozoic A-Type Granites in the Xiong’ershan Area along the Southern Margin of the North China Craton

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Journal of Earth Science 2024年第2期35卷 416-429页

作者： jinhong Xu Yuping jiang Shuli Hu Zhengwei Zhang Chengquan Wu Chaofei Zheng Xiyao Li Ziru Jin Sensen Zhang Yatao Zhou State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang550081China University of Chinese Academy of Sciences Beijing100049China Henan Province Non-ferrous Metals Geological Mineral Resources Bureau Zhengzhou450053China jiangmen Land Market Monitoring Center Jiangmen 529000China

Paleoproterozoic A-type granites are widely distributed in the southern margin of the North China Craton(SNCC),providing important information for understanding the Paleoproterozoic tectonic regimes in this *** paper reports newly obtained whole-rock compositions and zircon U-Pb ages for the Tieluping syenogranite porphyry(TLP)and Huoshenmiao alkali granite porphyry(HSM)in the *** from the TLP and HSM have U-Pb ages of 1805±12 and 1792±14 Ma,*** ages are taken to date the emplacement of these *** had high total alkali contents(K_(2)O+Na_(2)O>7.13 wt.%),with high 10000×Ga/Al ratios(3.06–3.41)and Zr+Y+Nb+Ce values(709 ppm–910 ppm)as well as high zircon saturation temperatures(864–970℃),indicative of A-type granite *** Y/Nb(1.75–3.32),Ce/Nb(7.72–9.72),and Yb/Ta(2.89–5.60)ratios suggested that TLP and HSM belonged to the A2-type *** negative whole rockε_(Nd)(t)values(−8.4 to−6.6)and negative zirconε_(Hf)(t)values(−15.9 to−6.3)confirmed that TLP and HSM were likely generated by the partial melting of an ancient continental ***εHf(t)(−7.4 to+4.0)values of inherited zircons in the TLP suggested that they were derived from the partial melting of Archean basement *** the geochemical similarity of the 1.80 Ga A-type granitoids in the SNCC,we propose that the TLP and HSM were formed in a post-collisional regime that was likely associated with the break-off of the Paleoproterozoic subducted *** of the asthenosphere provided huge heat to generate the regional 1.80 Ga A-type granite in the SNCC.

关键词： Paleoproterozoic A-type granite Post-collisional North China Craton tectonic geochemistry

资本市场开放提高企业创新的市场价值了吗——基于“沪深港通”的实证检验

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全国流通经济 2023年第20期 148-152页

作者：江锦虹暨南大学经济学院广东广州510632

本文基于沪深港通的准自然实验,选择2012—2019年沪深两市公司数据,建立固定效应的PSM-DID模型,探究资本市场开放政策对企业创新研发向市场价值转化机制的影响。研究结果证明,政策实施促进了企业创新研发向企业价值的转化,提高创新研发... 详细信息

本文基于沪深港通的准自然实验,选择2012—2019年沪深两市公司数据,建立固定效应的PSM-DID模型,探究资本市场开放政策对企业创新研发向市场价值转化机制的影响。研究结果证明,政策实施促进了企业创新研发向企业价值的转化,提高创新研发投入的转化效率,且通过了稳健性检验;进一步地,异质性检验表明该效应在委托代理问题较为严重或信息环境较好的公司更为显著,验证了资本市场开放政策对微观经济实体高质量发展的正向影响。

关键词：资本市场开放沪深港通创新研发转化

Thermodynamic Study on Process in Copper Converters(The slag-making stage)

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 187-192页

作者： Chunlin Chen Tuping Zhou Jiayun Zhang Shoukun Wei Xingxiang Lu Meng Bai jinhong jiang(Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China)(Guixi Smelter, jiangxi Province 333424, China) Metallurgy School University of Science and Technology Beijing Beijing 100083 China Guixi Smelter Jiangxi Province 335424 China

The so-called Goto's model was modified by introducing a parameter of the oxygen efficiency from industrial trials, as well as the selected and newly re-assessed thermodynamic data. The application of the model to copper converters in Guixi Smelter has been carried out by the combination of thermodynamic calculations with the mass and heat balance using the plant data obtained in industrial trials for many heats. For the slag-making stage, good agreements have been reached betWeen the calculated and measured temperature, blowing time as well as the contents for main elements in the matte and the slag. Relativel}'' large deviations for contents of Zn and Pb in the slag may be caused by the complex chemical composition of the real molten slag, which ma}; result in a large difference of γzn. and γPb,adopted with their real values. It is noted that the model can simulate the slag-making stage of copper converting process in industrial Pierce-Smith converters well.

关键词： copper converter thermodynamic study slag-making stage

Thermodynamic Study on Process in Copper Converters (The Copper-making Stage)

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 184-188页

作者： Chunlin Chen, Jiayun Zhang, Tuping Zhou, Shoukun Wei, Xingxiang Lu2), Meng Bai, jinhong jiang ( Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China Guixi Smelter, jiangxi, 335424) Metallurgy School University of Science and Technology Beijing Beijing 100083 China Guixi Smelter Jiangxi 335424 China

Theoretical calculations were based on thermodynamic equilibrium in the multi-component and multi-phase system with heat and mass balance as well as the oxygen efficiency to take account for the effects of process kinetics. The variations of temperature, mass fractions of dissolved oxygen and sulfur in blister copper, partial pressures for O2, S2, SO2 in gas phase for the copper-making stage were calculated. The model predicted temperature, time of blowing as well as mass of the blister copper at end points for 6 heats showed a fairly good agreements with corresponding plant data. The calculated content of 0.065% and content of 0.87% in blister copper were both at reasonable levels. Compared with the so called Goto model, the present model has very much improved process description of copper-making stage as well as the prediction of end points for a copper converter by introducing the oxygen efficiency.

关键词： Peirce-Smith copper converter thermodynamic model copper-making stage

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近代体操教育的流变及当代启示

体育科学 2022年第8期42卷 33-46页

作者：王水泉姜金红李永春浙江师范大学体育与健康科学学院浙江金华321004 浙江师范大学行知学院浙江金华321004

为厘清近代体操教育流变的脉络、各流派的特征,探寻其当代启示,研究认为,近代医学与思想领域对“身体教育”重要性的揭示,使近代体操教育的创立成为可能。18世纪中后期近代体操教育创立阶段,为建立属于每个国民的体操教育,突出完善人格... 详细信息

为厘清近代体操教育流变的脉络、各流派的特征,探寻其当代启示,研究认为,近代医学与思想领域对“身体教育”重要性的揭示,使近代体操教育的创立成为可能。18世纪中后期近代体操教育创立阶段,为建立属于每个国民的体操教育,突出完善人格教育的价值,以“自然性”为教育方法论,维劳密勾勒出了近代体操教育的基本方向,古茨穆斯承前启后,从实践出发,奠定了近代体操教育发展的基础,维斯则开启了“科学”研究体操教育的序幕,裴斯泰洛齐(Johan Heinrich Pestalozzi)从教育学、心理学角度洞察到了体操教育的人格陶冶价值。19世纪初,战争的威胁和工业的发展使德国、瑞典、丹麦成为了近代体操全球化的三大策源地。在国家主义背景下,政治性、道德性、军事性是之后各国近代体操教育的普遍特征。扬(Friedrich Ludwig Jahn)以“国民性”为思想依据的“德国体操”,突出精神的培养,重视器械体操。林(Per Henrik Ling)以生理学为理论基础的“瑞典体操”,带有鲜明的科学主义特征,重视徒手体操和轻器械体操。布克(Nicls Bukh)纠正军事化体操教育的弊端,创建的民众化的“基本体操”,突出强健性、柔韧性、灵敏性,重视基本体操、韵律体操、手持轻器械体操。19世纪中期施皮斯(Adolf Spiess)开创的近代学校体操教育必修制度重视集体徒手秩序体操。研究认为,反思“身体教育”“自然性”的内涵,正确认识身心关系,统筹考虑运动文化属性,有利于体操课程现代教育使命的更好实现。

关键词：身体教育自然性人格塑造国家主义臣民教育形式化