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zhang-Xuan thermal uplift and its genesis

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Progress in Natural Science:Materials International 2005年第8期15卷 725-732页

作者： SHAO ji'an1*, niu Shuyin2. {2. Lüqiao3.and LI Hongyang2.1. School of Earth and Space sciences, Peking University, beijing 100871, china 2. Shijiazhuang University of Economics, Shijiazhuang 05003., china 3. Geological Bureau of Inner Mongolia, Huhhot 01002., china) School of Earth and Space sciences Peking University Beijing 100871 China Shijiazhuang University of Economics Shijiazhuang 050031 China Geological Bureau of Inner Mongolia Huhhot 010020 China

Based on the researches of the Mesozoic thermal evolution history, the deformed structures, and fission track analysis of the zhangjiakou-Xuanhua area, we obtained the following knowledge: the area experienced in 140 Ma an underplating which is marked by emplacement of mantle derived magma; during 13.—110 Ma a series of eruptions and intrusions happened, and during 80—10 Ma a rising process occurred which is synchronous with the adjacent Taihang and Yanshan Mountains and was accompanied by a series of structures down slipping from the just formed zhang-Xuan uplift toward its periphery. Combining the zhang-Xuan thermal lift with the large detachment structure in Baoding depression of the North china Basin in the Late Mesozoic confirms that an even larger extensional tectonic background existed in North china during this period.

关键词： zhang-Xuan area underplating thermal uplift fission track extensional structure.

Solar-powered miniature robot for on-site oil spill treatment under magnetic steering

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Science china(Technological sciences) 2024年第7期67卷 2164-2175页

作者： WANG Ben CHEN YunRui WANG Yun ji FengTong LI HongYuan niu ShiChao HAN ZhiWu {2. YaBin GUO ZhiGuang College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Ministry of Education Key Laboratory of New Processing Technology for Nonferrous Metals and Materialsand School of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004China Key Laboratory for Bionic Engineering Ministry of Education Jilin UniversityChangchun 130022China Hubei Collaborative Innovation Centre for Advanced Organic Chemical Materials Ministry of Education Key Laboratory for the Green Preparation and Application of Functional MaterialsHubei UniversityWuhan 430062China Wellcome Trust/Cancer Research UK Gurdon Institute University of CambridgeCambridge CB21QNUK Department of Physiology Development and NeuroscienceUniversity of CambridgeCambridge CB21QNUK State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering ScienceBeijing Innovation Center for Engineering Science and Advanced TechnologyCollege of EngineeringPeking UniversityBeijing 100871China

Walking on the water surface is an effective method for miniature robots to transport payloads with dramatically decreased interfacial drag. Current aquatic robots reported are generally actuated by a beam of focused light that can trigger asymmetrical deformation, enabling the directional movement through horizontal momentum transfer of photoinduced actuation force to the water. However, the operations are heavily dependent on manual manipulation of the focused light, making the long-term actuation and application of the aquatic robots in vast scenarios challenging. Herein, we developed a kind of water striderinspired robot that can autonomously manage the motion on the water surface under solar irradiation, with their direction steerable by a magnetic field. The motion of this bioinspired robot on the water surface was achieved by the use of a solar cell panel as a driving module to enable propulsive motion based on the conversion of light-electric-mechanical energies. The superhydrophobic design of its leg surfaces enables the aquatic robots with weight-bearing and drag-reducing abilities. With the assistance of magnetic navigation, the bioinspired robot can continuously and controllably locomote to the oily spill floating on the water body and collect them with high efficiency. For further demonstration, the treatment of oil spills in a campus pool with high efficiency has also been achieved. This on-site oil-spill treating strategy, taking advantage of a home-made bioinspired robot actuated by natural sunlight under magnetic steering, shows great potential applications in water-body remediation.

关键词： miniature robot superhydrophobic water strider interfacial friction magnetic actuation

Southeastern extension of the Red River fault zone (RRFZ) and its tectonic evolution significance in western South china Sea

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Science china Earth sciences 2006年第8期49卷 839-850页

作者： LIU Baoming1,2.3. XIA Bin1, LI Xuxuan1,3. zhang Minqiang1,3. niu Binhua2. ZHONG Lifeng1, {2.N Qinghuan1,4 & {2. Shaocheng1,5 1. Key Laboratory of Marginal Sea Geology and Resources, Chinese Academy of sciences,Guangzhou 510640, china 2. china University of Geosciences (beijing), beijing 100083. china 3. Research Center of Science & Technology Department, CNOOC, beijing 10002., china 4. Guangzhou Marine Geological Survey, Ministry of Land & Resources, Guangzhou 510075, china 5. Ecole Polytechnique Montreal, H3.3.7, Canada Key Laboratory of Marginal Sea Geology and Resources Chinese Academy of Sciences Guangzhou China china University of Geosciences ({2.) Beijing China Research Center of Science & Technology Department CNOOC Beijing China Guangzhou Marine Geological Survey Ministry of Land & Resources Guangzhou China Ecole Polytechnique Montreal Canada

Recent geophysical surveys and basin modeling suggest that the No.1 fault in the Ying- gehai basin (YGHB) is the seaward elongation of the Red River fault zone (RRFZ) in the South china Sea (SCS). The RRFZ, which separates the South china and Indochina block, extends first along the Yuedong fault, offshore of Vietnam, and then continues southward and breaks off into two branches: the Lupar fault and the Tin{3.a fault. The southern extension of the Lupar fault dies out beneath the NW Borneo while the Tin{3.a fault extends southeast and reaches the Brunei-Sabah area. According to the gravity and geomagnetic data, and the tectonic evolution of the basins, there are different evolution histories between the Wan’an basin (WAB) and the basins in the Nansha block. The Tin{3.a fault may be the boundary between the Balingian block and the Nansha block. Hence, the line linking the Yue- dong fault and the Tin{3.a fault, which both are continental margin faults and strike-slip ones in the geological evolution histories, constitute the boundary between the Indochina and Nansha block. The Lupar fault, in contrast, is an intraplate fault within the Indochina block. The results provide new hints for reconstructing the tectonic evolution history of the RRFZ and the opening of the SCS, and also a framework for hydrocarbon prospecting in the region.

关键词： Red River fault zone, tectonic evolution, fault, extension, western South china Sea.

平焰燃烧器煤/NH_(3.燃烧特性实验研究

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煤炭学报 2024年第8期49卷 3667-3676页

作者：崔名双牛芳纪任山王乃继张鑫梁兴底一王圣烨北京天地融创科技股份有限公司北京100011 国家能源煤炭高效利用与节能减排技术装备重点实验室北京100013 陕西庆华汽车安全系统有限公司陕西西安710025

随着“碳达峰,碳中和”目标的提出,将煤与NH_(3.混燃逐步减少煤电是实现降碳的一种新途径,但煤/NH_(3.的混燃特性尚不清晰。因此,基于平焰燃烧器开展煤/NH_(3.燃烧实验,探究了掺氨比(E(NH_(3.),0~100%)、煤/NH_(3.注入方式(预混、非预混... 详细信息

随着“碳达峰,碳中和”目标的提出,将煤与NH_(3.混燃逐步减少煤电是实现降碳的一种新途径,但煤/NH_(3.的混燃特性尚不清晰。因此,基于平焰燃烧器开展煤/NH_(3.燃烧实验,探究了掺氨比(E(NH_(3.),0~100%)、煤/NH_(3.注入方式(预混、非预混)对燃烧特性的影响,采用相机、烟气分析仪,热电偶检测了火焰形态、燃烧器上方高度(Heights Above Burner,HAB)中心沿程烟气中气体组分及温度分布情况,并测定了飞灰中未燃碳的含量,得到:在燃烧初期,煤/NH_(3.争夺O_(2.的现象更明显,由于燃烧区NH_(3.燃烧产生的富水气氛,使得在预混低E(NH_(3.)下,CO与OH发生反应,CO质量浓度降低,而在高E(NH_(3.)下,一方面NH_(3.优先与O_(2.结合,导致大量碳不完全燃烧,另一方面,富水气氛促进了煤的气化反应,导致燃烧还原区的CO质量浓度大幅升高,最高可达19773.05 mg/Nm^(3.,但此过程改变了焦炭的孔隙结构,增加了焦炭的比表面积,加快了煤粉的燃烧进程,使预混条件下飞灰残炭量由13.90%(纯煤燃烧)降低至13.44%(E(NH_(3.)=80%),过早注入NH_(3.会减轻燃烧前期NH_(3.燃烧对煤粉的预热作用,降低在火焰反应区的燃烧强度;掺NH_(3.后NO_(x)排放量大幅上升,随着E(NH_(3.)增加,NO_(x)先增加后降低,且NO质量浓度峰值提前,未燃NH_(3.及氧体积分数分别是影响N_(2.O、NO_(2.生成的主要因素,增加煤/NH_(3.燃烧的停留时间、减少未燃NH_(3.体积分数、创造还原性气氛均是降低NO_(x)的有效方式;在预混高掺氨比(E(NH_(3.)≥80%、HAB=100 mm)及非预混工况下,CO_(2.%随着E(NH_(3.)增加呈现降低的趋势;预混E(NH_(3.)=40%~60%工况更有利于实现煤/NH_(3.的低氮、低碳、高效燃烧,煤粉掺NH_(3.燃烧存在相互促进和抑制作用,需根据实际情况采取有效措施以发挥煤/NH_(3.混燃的促进作用。

关键词：煤/NH_(3.混合燃料燃烧特性掺氨比煤/NH_(3.注入方式气体组分

A STUDY ON RELATION BETWEEN CONTINUOUS RAPID DEFORMATION AND EARTHQUAKLES

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大地测量与地球动力学 2003年第B12期23卷 79-82页

作者： niu Anfu, zhang {2.ng, Gao Fuwang, {2. Ping and Yan Xudong (Center for Analysis and Prediction, CEA, beijing 10003., china) Center for Analysis and Prediction CEA Beijing 100036 China

Continuous Rapid Deformation (CRD) may be an important precursor before some strong earthquakes with magnitude greater than \%M\%s5.0. This paper shows some characteristics of CRD, and proposes a method for identifying precursory CRD that is closely related to the process of earthquake preparation. From the deformation data in Yunnan Sichan provinces, we obtained the tilt and strain thresholds of 4.5ms/d and 5 ×10 -7 /d, respectively. Compared the tilt CRD in this region before 9 earthquakes (short term fore shocks and after shocks not included) with magnitude greater than 5.8 in the period from January of 1990 to May of 2.01, we found that 8 earthquakes occurred within 5 months after the CRD with a duration of more than 2. days and a tilt velocity of more than 4.5ms/d without false prediction, but with one failure in earthquake prediction. For the strain CRD, 5 earthquakes occurred after the CRD; there was no false prediction, but 4 earthquakes unpredicted. We have tried to increase the thresholds, but found either the failure ratio or the rate of false prediction increased, while the success rate not obvious increased.

关键词：连续急速变形 CKD 地震预报变形与地震的关系 K型斜坡地壳形变

2.2.年珠三角4个城市PM_(2.5)污染中金属元素吸入途径的健康风险评估

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上海预防医学 2024年第4期36卷 393-398页

作者：牛计伟黄素丽李晓恒张振季佳佳刘宁中国疾病预防控制中心现场流行病学培训项目北京100050 深圳市疾病预防控制中心广东深圳518055 广东省疾病预防控制中心广东广州511430

【目的】了解新型冠状病毒感染疫情下广东省珠三角城市空气中细颗粒物(PM_(2.5))污染特征及PM_(2.5)中金属元素吸入途径的健康风险。【方法】2.2.年在广州、深圳、佛山及珠海市等4个市10个区设置10个PM_(2.5)监测点,每月连续7 d采集空... 详细信息

【目的】了解新型冠状病毒感染疫情下广东省珠三角城市空气中细颗粒物(PM_(2.5))污染特征及PM_(2.5)中金属元素吸入途径的健康风险。【方法】2.2.年在广州、深圳、佛山及珠海市等4个市10个区设置10个PM_(2.5)监测点,每月连续7 d采集空气样品进行PM_(2.5)质量浓度及PM_(2.5)中12.金属元素成分分析。通过经典“四步法”对空气中PM_(2.5)金属元素与健康影响的致癌风险(CR)、慢性非致癌风险的评估。在CR评估中结合金属元素年龄敏感特征,引入年龄敏感因子,分析空气污染对人群健康影响。【结果】共采集样品818份,珠三角4个城市PM_(2.5)年均浓度(最小值~最大值,标准差)为3..17(1.00~166.00,2..06)μg·m^(-3.,低于GB 3.95—2.12.环境空气质量标准》二级浓度限值。4个城市PM_(2.5)浓度差异有统计学意义(P3.70(4.00~3..00,5.93.μg·m^(-3.,最高是1月57.73.14.00~146.00,2..96)μg·m^(-3.。日平均浓度超过二级浓度限值的共2. d,主要分布在1、11月。PM_(2.5)中元素的年均质量浓度铝(Al)>锰(Mn)>铅(Pb)>砷(As)>镍(Ni)>铬(Cr)>硒(Se)>锑(Sb)>镉(Cd)>铊(Tl)>铍(Be)>汞(Hg)。AS、Mn具有人群慢性非致癌风险,Cr、As、Cd、Be、Ni存在人群CR。【结论】珠三角4个城市PM_(2.5)污染水平低且有差异性,临海城市低于非临海城市,全年呈先降后升的特征。4个城市PM_(2.5)中金属元素除Be、Ni外质量浓度排序基本相同。PM_(2.5)中As、Mn显示有一定程度的慢性非致癌风险,As、Cr、Cd、Ni、Be存在一定程度的CR。4个城市均须采取有效干预措施,继续加强空气中Cr、As、Cd、Mn的污染管控和健康防护,控制空气污染导致的健康负担。

关键词：金属元素 PM_(2.5) 空气污染健康风险吸入

淮河流域细颗粒物化学组分时空特征及驱动因素分析

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环境科学 2024年第10期45卷 5650-5660页

作者：刘晓咏牛继强刘航张一丹颜俊闫军辉苏方成信阳师范大学地理科学学院信阳464000 信阳师范大学河南省水土环境污染协同防治重点实验室信阳464000 中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室北京100029 郑州大学化学学院郑州450001

基于淮河流域3.个城市2.15~2.2.年的细颗粒物(PM_(2.5))及其组分数据集,分析了污染物的时空分布格局,利用随机森林模型考察了气象因子对PM_(2.5)浓度的影响.采用KZ(Kolmogorov-Zurbenko)滤波和多元线性回归(MLR)对PM_(2.5)、硫酸盐(SO_(... 详细信息

基于淮河流域3.个城市2.15~2.2.年的细颗粒物(PM_(2.5))及其组分数据集,分析了污染物的时空分布格局,利用随机森林模型考察了气象因子对PM_(2.5)浓度的影响.采用KZ(Kolmogorov-Zurbenko)滤波和多元线性回归(MLR)对PM_(2.5)、硫酸盐(SO_(4)^(2.))、硝酸盐(NO_(3.^(-))、铵盐(NH_(4)^(+))、有机物(OM)和黑炭(BC)的原始序列进行气象调整,定量气象条件的影响.结果表明,2.15~2.2.年淮河流域PM_(2.5)、SO_(4)^(2.)、NO_(3.^(-)、NH_(4)^(+)、OM和BC的变化速率分别为-4.71、-0.99、-1.05、-0.77、-1.01和-0.19μg·(m^(3.·a)^(-1).PM_(2.5)及其组分浓度高值集中在淮河流域中部和西部区域,而沿海及南部城市的浓度较低.PM_(2.5)短期、季节和长期分量对3.个城市PM_(2.5)原始序列总方差的贡献率分别为51.6%、3..9%和7.0%,沿海城市更受短期分量影响.2.15~2.18年气象条件不利于淮河流域PM_(2.5)浓度的降低,2.19~2.2.年气象条件有利于PM_(2.5)浓度的降低.2.15~2.2.年气象条件对淮河流域PM_(2.5)、SO_(4)^(2.)、NO_(3.^(-)、NH_(4)^(+)、OM和BC长期分量下降的贡献率分别为2..3.、2..1%、3..0%、2..3.、2..8%和2..6%.气象条件对安徽、山东、江苏和河南省淮河流域城市PM_(2.5)长期分量降低的贡献率分别为43.4%、2..6%、2..5%和2..6%.随着淮河流域PM_(2.5)浓度降低,硫氧化率(SOR)明显上升,而氮氧化率(NOR)变化不大.

关键词： PM_(2.5) 化学组分 KZ滤波时空分布气象影响

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自激波动注水振荡波传播规律实验

水动力学研究与进展（A辑） 2004年第3期19卷 370-374页

作者：李根生黄中伟张德斌牛继磊张武威高国强石油大学北京昌平102249 石油大学华东山东东营257061 胜利油田山东东营257000

　本文提出了自激波动注水新思想,目的在于改进油田注水井中传统的注水方式,降低注水压力、延长修井周期。首先介绍了自振空化喷嘴工作原理。其次,在地面实验台架上测试了喷嘴出口射流的频谱特性、不同频率下压力振荡沿套管径向和轴向... 详细信息

　本文提出了自激波动注水新思想,目的在于改进油田注水井中传统的注水方式,降低注水压力、延长修井周期。首先介绍了自振空化喷嘴工作原理。其次,在地面实验台架上测试了喷嘴出口射流的频谱特性、不同频率下压力振荡沿套管径向和轴向的传播及衰减规律。实验发现,套管内自振空化射流频谱具有宽频带噪声特性,空化射流产生的振荡波能量主要集中在2.KHz以内的频率段,在该频率段内,5KHz以内的振荡信号沿套管轴向衰减较慢,之后衰减加快;流体振荡沿套管径向传播距离达100cm以上,沿轴向传播距离可达600cm以上。

关键词：自激波动注水射流空化传播

Building energy efficiency and COVID-19 infection risk:Lessons from office room management

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建筑模拟(英文) 2023年第8期16卷 1425-1438页

作者： Nan zhang Tingrui Hu Menghan niu Baotian Chang Nhantumbo Palmira Elisa Peng Xue Ying {2. beijing Key Laboratory of Green Built Environment and Energy Efficient Technology Beijing University of TechnologyBeijingChina

To prevent COVID-19 outbreaks,many indoor environments are increasing the volume of fresh air and running air conditioning systems at maximum ***,it is essential to consider the comfort of indoor occupants and energy consumption simultaneously when controlling the spread of *** this study,we simulated the energy consumption of a three-storey office building for postgraduate students and teachers at a university in *** on an improved Wells-Riley model,we established an infection risk-energy consumption model considering non-pharmaceutical interventions and human *** infection risk and building energy efficiency under different room occupancy rates on weekdays and at weekends,during different seasons were then *** consumption,based on the real hourly room occupancy rate during weekdays was 43.–55%lower than energy consumption when dynamic room occupancy rate was not *** all people wear masks indoors,the total energy consumption could be reduced by 3.1}–45%and the proportion of energy used for ventilation for epidemic prevention and control could be reduced by 2.%–3.%during all *** only graduate students wear masks in rooms with a high occupancy,total energy consumption can be reduced by 15%–2.%.After optimization,compared with the strict epidemic prevention and control strategy(the effective reproductive number Rt=1 in all rooms),energy consumption during weekdays(weekends)in winter,summer and transition seasons,can be reduced by 45%(74%),43.(69%),and 55%(78%),*** results of this study provide a scientific basis for policies on epidemic prevention and control,carbon emission peak and neutrality,and Healthy {2. 2.3..

关键词： building energy efficiency COVID-19 room occupancy rate carbon peaking and neutrality non-pharmaceutical intervention