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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 683-685页

作者： fang Xu Yang Bai Kai Jiang li-jie qiao College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China Corrosion and Protection Center Key Laboratory of Environmental Fracture （Ministry of Education） University of Science and Technology Beijing Beijing 100083 China

The electromagnetic properties of Ba2Co1.8Cu0.2Fe12O22 （Co2Y） and Ba3Co2Fe23.4Zn0.6O41 （Co2Z） were studied by measuring microwave scattering *** the transmission spectra of Ba2Co1.8Cu0.2Fe12O22,a forbidden band emerges due to ferromagnetic resonance,and the permeability will turn to negative in the vicinity of the ferromagnetic resonance *** the complex permittivity spectra of Ba3Co2Fe23.4Zn0.6O41,the negative permittivity can be obtained due to dielectric ***,Co2Y and Co2Z can be used to construct left-handed materials possessing negative permeability and negative permittivity simultaneously.

关键词： left-handed materials hexagonal ferrite ferromagnetic materials permeability permittivity resonance

Superatom-assembled boranes,carboranes,and low-dimensional boron nanomaterials based on aromatic icosahedral B_(12)and C_(2)B_(10)

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Nano Research 2024年第7期17卷 6734-6740页

作者： qiao-qiao Yan Yan-fang Wei Qiang Chen Yue-Wen Mu Si-Dian li Institute of Molecular Science Shanxi UniversityTaiyuan 030006China

Using the experimentally known aromatic icosahedral superatoms I_(h)B_(12)H_(12)2−and D_(5d)1,12-C_(2)B_(10)H_(12)as building blocks and based on extensive density functional theory calculations,we predict herein a series of core–shell superpolyhedral boranes and carboranes in a bottom-up approach,including the high-symmetry Th B_(12)@B_(152)H_(72)2−(2),C2h C_(2)B_(10)@B_(152)H_(72)(3),D_(3d)B_(12)@B_(144)H_(66)(4),I_(h)B_(12)@C_(24)B_(12)0H_(72)2−(6),and D_(5d)C_(2)B_(10)@C_(24)B_(12)0H_(72)(7).More interestingly,the superatom-assembled linear D2h B_(36)H_(32)^(2−)(8),close-packed planar D_(3d)B_(84)H_(60)^(2−)(10),and nearly close-packed core−shell D_(3d)B_(12)@B144H_(6)6(4)can be extended periodically to form the one-dimensional(1D)α-rhombohedral borane nanowire B_(12)H_(10)(Pmmm)(9),two-dimensional(2D)α-rhombohedral monolayer borophane B_(12)H_(6)(P m1)(11),and the experimentally known three-dimensional(3D)α-rhombohedral boron(R m)(12)which can be viewed as an assembly of the monolayer B_(12)H_(6)(11)staggered in vertical direction,setting up a bottom-up strategy to form low-dimensional boron-based nanomaterials from their borane“seeds”via partial or complete *** bonding analyses indicate that the high stability of these nanostructures originates from the spherical aromaticity of their icosahedral B_(12)or C_(2)B_(10)structural units which possess the universal skeleton electronic configuration of 1S21P61D101F8 following the Wade’s n+1 *** infrared(IR)and Raman spectra of the most-concerned neutral B_(12)@B144H_(6)6(4)and C_(2)B_(10)@C_(24)B_(12)0H_(72)(7)are computationally simulated to facilitate their experimental characterizations.

关键词： superatom-assembling bottom-up approach density functional theory superpolyhedral boranes superpolyhedral carboranes borophanes

Microstructure and properties of indium tin oxide thin films deposited by RF-magnetron sputtering

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Rare Metals 2006年第4期25卷 359-364页

作者： li Shitao qiao Xueliang CHEN Jianguo JIA fang WU Changle State Key Laboratory of Plastic Forming Simulation and Die ＆ Mould Technology Huazhong University of Science and Technology Wuhan 430074China

Tin-doped indium oxide （ITO） thin films were prepared using conventional radio frequency （RF） planar magnetron sputtering equipped with IR irradiation using a ceramic target of In2O3/SnO2 with a mass ratio of 1：1 at various IR irradiation temperatures T1 （from room temperature to 400℃）. The refractive index, deposited ratio, and resistivity are functions of the sputtering Ar gas pressure. The microstructure of ITO thin films is related to IR T1, the crystalline seeds appear at T1= 300℃, and the films are amorphous at the temperature ranging from 27℃ to 400℃. AFM investigation shows that the roughness value of peak-valley of ITO thin film （Rp-v） and the surface microstructure of rio thin films have a close relation with T1. The IR irradiation results in a widening value of band-gap energy due to Burstein-Moss effect and the maximum visible transmittance shifts toward a shorter wavelength along with a decrease in the film＇s refractive index. The plasma wavelength and the refractive index of ITO thin films are relative to the T1. XPS investigation shows that the photoelectrolytic properties can be deteriorated by the sub-oxides. The deterioration can be decreased by increasing the oxygen flow rote （fo2）, and the mole ratio of Sn/In in the samples reduces with an increase info2.

关键词： indium-tin oxide (ITO) photoelectrolytic properties RF-magnetron sputtering IR irradiation temperature microstructure refractive index

基于改进并行子空间优化方法的机床主轴设计研究

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机电工程 2015年第6期32卷 788-792页

作者：刘凯罗伟林赖宇阳方立桥福州大学机械工程与自动化学院福建福州350116 北京树优信息技术有限公司北京100062

为了使CSSO方法在系统级优化时能用于自主筛选来自各子学科间的设计变量的最优值以提高系统级优化效率和收敛速度,提出了一种改进型的并行子空间优化方法(improved concurrent subspace optimization,I-CSSO)。该方法在传统CSSO方法基... 详细信息

为了使CSSO方法在系统级优化时能用于自主筛选来自各子学科间的设计变量的最优值以提高系统级优化效率和收敛速度,提出了一种改进型的并行子空间优化方法(improved concurrent subspace optimization,I-CSSO)。该方法在传统CSSO方法基础上通过增加一个自动筛选程序,即将各子学科优化方案及系统级优化方案进行了对比,从中优选出最优方案作为下一轮迭代的初始方案进行了优化,同时应用拉丁超立方试验设计方法采取样本点并构建了数据库,近似模型基于径向基神经网络模型。以某一机床主轴设计优化为例,基于Isight平台搭建了所设计的I-CSSO方法框架,并与传统的CSSO方法进行了对比。研究结果表明:所提出的I-CSSO方法有效提高了算法的计算效率。

关键词：多学科优化设计并行子空间优化方法拉丁超立方近似模型机床主轴设计

Impact of an artificial chute cutoff on the river morphology and flow structure in Sipaikou area of the Upper Yellow River

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Journal of Mountain Science 2021年第12期18卷 3275-3290页

作者： qiao qiao li Chun-guang JING He-fang HUANG ling-xiao YANG Cheng School of Civil and Hydraulic Engineering Ningxia UniversityYinchuan 750021China School of Civil Engineering North Minzu UniversityYinchuan 750021China School of Information Engineering Ningxia UniversityYinchuan750021China

Artificial chute cutoff can fundamentally eliminate the threat of flood caused by the meandering river,but it significantly changes its morphodynamic *** adjustments after cutoff are rapid,which makes it difficult to study the interaction between river morphology and flow structure only through field ***,numerical simulations can provide insights into the hydrodynamic characteristics after artificial chute *** this study,both field measurement and numerical simulation are employed to investigate the flow structure and bed morphology caused by an artificial chute cutoff in Sipaikou area of the Upper Yellow River in *** measured hydrological data provide boundary conditions and initial values for the numerical *** field measurement results reveal that the concave bank of the study area is severely scoured up to 270 m after the artificial cutoff,and a 20 m deep scour hole and a 2.26 km long pool are formed at the entrance and near the left bank of the chute *** numerical simulation results of velocity at typical cross-sections are in good agreement with the measurement *** separation and stagnation zones are observed near the right bank during the low flow conditions(discharge of at least 902 m^(3)/s),but this phenomenon is not seen during larger flow conditions(discharge exceeds 2000 m^(3)/s).Interestingly,flow recirculation zones are also found near the left and right banks of the scour ***,a long flux belt is formed at the scour hole and the ***,the impact of the bed topography on the hydrodynamic characteristics is relatively prominent when the discharge is small,while the impact on the river banks and river bed is more noticeable when the water discharge is *** addition,high shear stress is observed near the left bank at the downstream of the studied area,which indicates that the left bank at the downstream is still being *** results suggest that bank prote

关键词： Artificial chute cutoff Flow recirculation Hydrodynamic Scour hole Yellow River

Analysis of the extremely cold and heavy snowfall in North America in January 2015

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Atmospheric and Oceanic Science Letters 2016年第2期9卷 75-82页

作者： CUI Hong-yan qiao fang-li First Institute of Oceanography State Oceanic Administration Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration

With global warming and declining Arctic sea ice area in autumn observed by satellites since 1979, anomalous cold snaps in recent winters have affected large parts of North America, Europe, and East Asia. In January 2015, North America suffered extremely cold and heavy snowfall events. As revealed in this paper, the NCEP reanalysis data show that the temperature decreased significantly in January 2015 in North America, including the air temperature in the troposphere and the surface air temperature. Moreover, snow cover increased obviously in January 2015 in North America, while there was a significant negative anomaly of geopotential height. The wind formed the anomalous pattern, which favored cold currents blowing to the North American continent from the polar region, and bringing plenty of water vapor. Our results suggest that the anomalous north wind and decreasing westerly jet stream, which allowed cold and moist air to easily penetrate the North American continent from the Arctic, was one of the main reasons for the extremely cold and heavysnow winter of 2015 in North America.

关键词： Snowfall cold winter atmospheric circulation geopotential height strong north wind

珍稀食用菌紫陀螺菌三峡区域资源调查与化学成分分析

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中国食用菌 2022年第2期41卷 43-47页

作者：谭爱华李方桥邓梦匀胡飞飞湖北三峡职业技术学院湖北宜昌443000 三峡大学生物与制药学院天然产物研究与利用湖北省重点实验室湖北宜昌443002

对紫陀螺菌的资源分布和化学成分进行研究,采用走访调查、实地考察及定点测定的方法,确定紫陀螺菌子实体为单生或群生,多呈带状分布,主要分布在西陵峡南岸、海拔为400 m~800 m的山脊及山腰中。采用葡聚糖凝胶柱层析、正相硅胶柱层析、... 详细信息

对紫陀螺菌的资源分布和化学成分进行研究,采用走访调查、实地考察及定点测定的方法,确定紫陀螺菌子实体为单生或群生,多呈带状分布,主要分布在西陵峡南岸、海拔为400 m~800 m的山脊及山腰中。采用葡聚糖凝胶柱层析、正相硅胶柱层析、高效液相色谱等分离手段,结合核磁共振波谱分析方法,对紫陀螺菌子实体和发酵液的化学成分进行研究,最终从紫陀螺菌子实体的甲醇提取物中分离得到4个化合物,紫陀螺菌发酵液中得到1个化合物。经核磁共振波谱鉴定,这5个化合物分别为邻苯二甲酸-双(2’-乙基庚基)酯,邻苯二甲酸-二(2-乙基己基)酯,D-半乳糖醇,腺苷,吲哚-3-羧酸甲酯。

关键词：紫陀螺菌资源调查化学成分分离鉴定

Influential factors of spatial performance in metro-led urban underground public space:A case study in Shanghai

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Underground Space 2023年第1期8卷 229-251页

作者： Chen-Xiao Ma fang-Le Peng Yong-Kang qiao Hu li Research Center for Underground Space&Department of Geotechnical Engineering Tongji UniversityShanghai 200092PR China Ji’nan Rail Transit Group Co. Ltd.Ji’nan 250014Shandong ProvincePR China

Spatial performance measures the space usage of each underground segment in metro-led urban underground public space(UUPS).It usually varies in different UUPS segments and at different *** environmental factors and space attractors can influence spatial performance in UUPS including spatial configurations,transportation facilities,space design characteristics,and commercial and work-ing *** study intends to figure out the temporal and spatial distribution patterns of spatial performance in UUPS and then reveal the main influential factors and their impact *** UUPS in Jiangwan–Wujiaochang Sub-center was selected as the study *** counting methods and multiple regression models were employed to collect the pedestrian data and quantitatively analyze the correlations between pedestrian flows and candidate influential *** study verified that spatial configurations were the most important factors instead of underground or surface *** existed an interactive effect among pedestrian move-ments,spatial configurations,and commerce distribution in metro-led *** width and the distribution of metro stations could partly affect spatial *** influential mechanisms of metro stations were different on weekdays and at *** segments belonging to shopping malls in UUPS had a negative impact on spatial performance only on *** of this study can provide insights for more efficient layout planning and design of metro-led UUPS in Chinese metropolitan cities.

关键词： Urban underground public space Metro-led area Spatial performance Cordon count Multiple regression method

煤气化工序高浓度含酚废水磷酸三丁酯萃取试验研究及组合处理工艺初探

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化学与生物工程 2018年第11期35卷 55-58页

作者：古永红张战利杨晓勤李方桥文晓敏湖北三峡职业技术学院湖北宜昌443000 湖北宜化集团有限责任公司湖北宜昌443000

以磷酸三丁酯(TBP)为络合萃取剂、煤油为稀释剂,对宜昌某化工厂煤气化工序产生的废水进行萃取脱酚试验研究,优化了萃取时间、萃取温度、pH值、油水体积比和TBP含量等影响酚去除率的因素,并结合煤气化废水特点,提出了"曝气-沉淀-萃取-气... 详细信息

以磷酸三丁酯(TBP)为络合萃取剂、煤油为稀释剂,对宜昌某化工厂煤气化工序产生的废水进行萃取脱酚试验研究,优化了萃取时间、萃取温度、pH值、油水体积比和TBP含量等影响酚去除率的因素,并结合煤气化废水特点,提出了"曝气-沉淀-萃取-气浮"组合处理工艺。结果表明,经该组合工艺处理后的出水COD<1 100mg·L^(-1),总酚含量<50mg·L^(-1),总酚去除率达到98%以上,可满足生化处理系统进水要求。

关键词：煤气化高浓度含酚废水络合萃取组合处理工艺

Vibration Characteristics of Rotor System with Loose Disc Caused by the Insufficient Interference Force

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Chinese Journal of Mechanical Engineering 2022年第3期35卷 297-311页

作者： Zhinong li fang qiao Wenxiu Lu Jie liu Dong Wang Fulei Chu Key Laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063China Laboratory of Science and Technology on Integrated Logistics Support National University of Defense TechnologyChangsha 410073China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Mechanical Systems and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

The rotating parts looseness is one of the common failures in rotating *** current researches of looseness fault mainly focus on non-rotating ***,the looseness fault of disc-shaft system,which is the main work part in the rotor system,is almost ***,a dynamic model of the rotor system with loose disc caused by the insufficient interference force is proposed based on the contact model of disc-shaft system with the microscopic surface topography,the vibration characteristics of the system are analyzed and discussed by the number simulation,and verified by the *** results show that the speed of the shaft,the contact stiffness,the clearance between the disc and shaft,the damping of the disc and the rotational damping have an influence on the rotation state of the *** the rotation speed of the disc and the shaft are same,the collision frequency is mainly composed of one frequency multiplication component and very weak high frequency multiplication *** the rotation speed of the disc and the shaft is close,the vibration of the disc occurs a beat vibration phenomenon in the horizontal ***,a periodical similar beat vibration phenomenon also occurs in the waveform of the disc-shaft displacement *** collision frequency is mainly composed of a low frequency and a weak high frequency *** the rotation speed of the disc and the shaft has great difference,the collision frequency is mainly composed of one frequency multiplication,a few weak high frequency multiplication components and a few low frequency multiplication *** the reduction of the relative speed of the disc,the trajectory of the disc changes from circle-shape to inner eight-shape,and then to *** the inner eight-shape,the inner ring first gradually becomes smaller and then gradually becomes larger,and the outer ring is still getting *** obtained research results in this paper has importa

关键词： Rotor system with loose disc Rotor dynamics Nonlinear dynamic characteristic Nonlinear vibration Insufficient interference force Fault diagnosis