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基于综合污染指数法的声环境质量评价

河北环境工程学院学报 2024年第3期34卷 84-88页

作者：张清添福建省泉州环境监测中心站福建泉州362000

基于综合污染指数法,评价了2017—2022年泉州市中心城区城市区域环境噪声、道路交通噪声和功能区环境噪声。2017—2022年泉州市中心城区城市区域环境噪声的综合污染指数为1.70~1.83,评价结果为二级,即较好。道路交通噪声的综合污染指数... 详细信息

基于综合污染指数法,评价了2017—2022年泉州市中心城区城市区域环境噪声、道路交通噪声和功能区环境噪声。2017—2022年泉州市中心城区城市区域环境噪声的综合污染指数为1.70~1.83,评价结果为二级,即较好。道路交通噪声的综合污染指数为0.82~2.03,评价结果有好、较好和一般。功能区噪声污染综合指数为0.61~10.7,同一个功能区不同年份下的污染综合指数值存在一定的差异;评价等级以2类区的为最佳,评价等级均不低于一般级别;以4类区的为最差,评价等级均为差。相比等效声级单因子评价法,综合污染指数法综合考虑等效声级的大小、噪声污染级、受噪声影响的人数、超标率、超标路段长度等因素,其评价结果更能反映出声环境质量的实际情况,评价结果更加合理。

关键词：综合污染指数单因子评价法区域环境噪声道路交通噪声

Fundamental Issues Towards Unified Design Theory of Recycled and Natural Aggregate Concrete Components

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Engineering 2023年第10期29卷 188-197页

作者： Jianzhuang Xiao Kaijian zhang Tao Ding qingtian zhang Xuwen Xiao Department of Structural Engineering Tongji UniversityShanghai 200092China College of Civil Engineering and Architecture Guangxi UniversityNanning 530004China College of Civil Engineering Fuzhou UniversityFuzhou 350116China

In the past 20 years,recycled aggregate concrete(RAC),as a type of low-carbon concrete,has become a worldwide focus of ***,the design methodology for RAC structural components remains a ***,demands for a unified design of natural aggregate concrete(NAC)and RAC components have been ***,this study analyses the necessity of a unified design theory and provides an in-depth demonstration of the strength determination,compressive constitutive relationship,and design method of concrete *** coefficient of variation of RAC strength is found to be generally higher than that of NAC *** compressive and tensile strengths of RAC can be defined and determined using the same method as that used for *** uniaxial compressive constitutive relationship between NAC and RAC has a unified mathematical ***,the elastic modulus of RAC decreases,and its brittleness exhibits an increasing trend compared with that of ***,to unify the design formulae of RAC and NAC components for bearing capacity,modification factors for RAC components are proposed considering safety and ***,the feasibility of the proposed unified time-dependent design theory is demonstrated in terms of conceptual design and structural measures considering the effects of strength degradation and reinforcement *** is believed that this study enriches and develops the basic theory of concrete structures.

关键词： Recycled aggregate concrete(RAC) Natural aggregate concrete(NAC) Strength determination Constitutive relation Reliability Unified design theory

Time-dependent wave packet approach to the pulse delay effect upon RbI photoelectron spectrum

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Science China Chemistry 2006年第3期49卷 214-218页

作者： LIU Chunhua MENG qingtian zhang Qinggang College of Physics and Electronics Shandong Normal University Jinan 250014 China College of Physics and Electronics Shandong Normal University Jinan 250014 China College of Physics and Electronics Shandong Normal University Jinan 250014 China

The time-resolved photoelectron spectrum (TRPES) of Rbl molecule is simulatedusing the time-dependent wave-packet method. Both the normal three-photon ionization process andauto-ionization process are involved in the simulation. The calculated results show that the changeof delay time will influence the shape of the photoelectron spectrum (PES), and the influence issubstantially due to the existence of the crossing between excited states and the strong laser fieldwhich will change the position of relevant curves.

关键词： time-dependent wave packet method, multiphoton ionization (MPI), time-resolved photoelectron spectrum (TRPES), auto-ionization.

曲线拟合与分段函数组合法在瓦斯抽采量预测中的研究与应用

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煤炭技术 2024年第1期43卷 185-189页

作者：程磊王鑫张清田河南理工大学安全科学与工程学院河南焦作454003 河南理工大学煤炭安全生产与清洁高效利用省部共建协同创新中心河南焦作454003 焦作煤业(集团)有限责任公司科学技术研究所河南焦作454002

为减少矿井煤与瓦斯突出、瓦斯爆炸等事故的发生,将井下瓦斯及时抽出是必要的,因此对瓦斯抽采量进行准确地预测愈发重要。在神经网络法、多元线性回归法等预测方法的基础上,根据瓦斯抽采量在时间效应下变化波动大的特性,提出了曲线拟合... 详细信息

为减少矿井煤与瓦斯突出、瓦斯爆炸等事故的发生,将井下瓦斯及时抽出是必要的,因此对瓦斯抽采量进行准确地预测愈发重要。在神经网络法、多元线性回归法等预测方法的基础上,根据瓦斯抽采量在时间效应下变化波动大的特性,提出了曲线拟合与分段函数组合法。此方法以瓦斯抽采量衰减为界将瓦斯抽采分为前、后2个阶段,根据实测数据作抽采纯量随时间变化曲线并对变化曲线进行拟合,根据拟合曲线列出预测瓦斯抽采量的计算公式,用于对抽采量进行预测。分别对九里山矿、古汉山矿进行后段抽采量预测与实际的比较,其中九里山矿得到后段预测值的最小相对误差为0.63%,最大相对误差为2.34%,古汉山矿得到后段预测值的最小相对误差为0.09%,最大相对误差为3.23%。表明曲线拟合与分段函数组合法对井下瓦斯抽采量预测是可行的,对井下瓦斯治理具有重要的意义。

关键词：瓦斯抽采抽采量预测曲线拟合与分段函数组合法时间效应瓦斯治理

Preparation of Nitrogen-doped Carbon Dots from Coke Powder as a Fluorescent Chemosensor for Selective and Sensitive Detection of Cr (Ⅵ)

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Journal of Wuhan University of Technology(Materials Science) 2022年第6期37卷 1096-1104页

作者： MENG Juan LI Shiqian DING Ling ZHOU Chuang JIANG Rui zhang qingtian CHENG Zhengzai GAUTHIER Mario HU Ya WU Lin School of Chemistry and Chemical Engineering Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steel makingWuhan University of Science and TechnologyWuhan 430081China Fujian Universities and Colleges Engineering Research Center of Modern Facility Agriculture of Fujian University Fujian Polytechnic Normal UniversityFuqing 350300China Chemistry Department University of WaterlooWaterlooOntarioN2L 3G1Canada

The nitrogen-doped carbon dots(N-CDs)were prepared by using coke powder as carbon source and one-step hydrothermal *** N-CDs were studied as a fluorescent chemosensor for determining Cr(Ⅵ)in *** selective,sensitive,reproducibility and stability of as-prepared N-CDs were *** morphology,composition and properties of N-CDs were characterized by a series of *** fluorescence quenching of N-CDs by Cr(Ⅵ)was *** experimental results reveal that the obtained N-CDs have great hydrophilicity and strong luminescence properties,which demonstrates the successful doping of nitrogen into the *** surface-active groups and emission wavelength range of CDs increase due to the electronegativity and electron donor effect of doping N ***,the N-CDs exhibit good photochemical properties for the detection of Cr(Ⅵ),including a wide linear range from 0.3 to 200μM(R^(2)=0.9935)and a low detection limit of 0.10μM at the signal-to-noise ratio of 3(S/N=3).Moreover,the N-CDs as a sensor was used successfully for Cr(Ⅵ)detection in real water samples with recovery rates of 99.9%-110.6%.This sensor also shows highly reproducibility and *** N-CDs fluorescent chemical sensor may be a potential candidate for applying in the field of other fluorescent chemical sensing,catalysis,photoelectric devices and other fields.

关键词： carbon dots nitrogen doping preparation fluorescence detection Cr(Ⅵ)

Application of Gaussian Beam Summation Migration in Reflected In-seam Wave Imaging

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 276-284页

作者： HAN Jianguang LÜqingtian zhang Zhiheng YANG Shun WANG Shuo Chinese Academy of Geological Sciences Beijing 100037China Shandong Taishan Resources Exploration Co. Ltd.Jinan 250104China

The geological conditions for coal mining in China are complex,with various structural issues such as faults and collapsed columns seriously compromising the safety of coal mine ***-seam wave exploration is an effective technique for acquiring detailed information on geological structures in coal seam working ***,the existing reflected in-seam wave imaging technique can no longer meet the exploration precision requirements,making it imperative to develop a new reflected in-seam wave imaging *** study applies the Gaussian beam summation(GBS)migration method to imaging coal seams'reflected in-seam wave ***,with regard to the characteristics of the reflected in-seam wave data,methods such as wavefield removal and enveloped superposition are employed for the corresponding wavefield separation,wave train compression and other processing of reflected in-seam ***,imaging is performed using the GBS migration *** feasibility and effectiveness of the proposed method for reflected in-seam wave imaging are validated by conducting GBS migration tests on 3D coal-seam fault models with different dip angles and *** applying the method to reflected in-seam wave data for an actual coal seam working face,accurate imaging of a fault structure is obtained,thereby validating its practicality.

关键词： reflected in-seam wave Gaussian beam summation migration numerical tests fault

CLEAR: a full-stack chip-in-loop emulator for analog RRAM based computing-in-memory system

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Science China(Information Sciences) 2023年第12期66卷 293-294页

作者： Ruihua YU Wenqiang zhang Bin GAO Yiwen GENG Peng YAO Yuyi LIU qingtian zhang Jianshi TANG Dong WU Hu HE Ning DENG He QIAN Huaqiang WU School of Integrated Circuits Beijing National Research Center for Information Science and Technology(BNRist)Tsinghua University

Deep neural networks(DNNs) have undergone tremendous advancement in several practical applications, such as object detection and text generation, over the last few years,leading to a huge demand for increased computing efficiency of hardware. Resistive random-access memory(RRAM)-based computing-in-memory(CIM) chip has been investigated as a promising candidate to reduce the requirement for memory bandwidth [1].

关键词： ARCHITECTURE

葡萄VvMET1-1基因在葡萄和拟南芥中的功能研究

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中外葡萄与葡萄酒 2024年第3期 1-12页

作者：王风霞丁亭亭刘蕙萍李科杨国伟李傲张庆田 Chebukin Pavel 任凤山王鹏飞山东省葡萄研究院山东济南250100 俄罗斯瓦维洛夫植物研究所海参崴690014 山东省农业科学院山东济南250100 山东省酿酒葡萄与葡萄酒技术创新中心山东烟台265600

DNA甲基化修饰对于植物的生长发育十分重要,而MET1是植物中重要的甲基转移酶,能维持植物的CG位点甲基化修饰。为了研究葡萄MET1基因的功能及对植物发育的影响,将葡萄VvMET1-1基因转入葡萄胚性愈伤组织和拟南芥中进行研究。本研究选择35S... 详细信息

DNA甲基化修饰对于植物的生长发育十分重要,而MET1是植物中重要的甲基转移酶,能维持植物的CG位点甲基化修饰。为了研究葡萄MET1基因的功能及对植物发育的影响,将葡萄VvMET1-1基因转入葡萄胚性愈伤组织和拟南芥中进行研究。本研究选择35S::VvMET1-1-GFP表达载体转入葡萄胚性愈伤组织后检测到明显的GFP信号,且该胚性愈伤组织能被成功诱导为体细胞胚,表明VvMET1-1首次被成功转入葡萄胚性愈伤组织中并且不影响胚性愈伤组织的发育和分化。VvMET1-1被转入拟南芥中发现,该基因能影响拟南芥叶片的长度和宽度,但是不影响植株形态和种子发育;转录组数据分析表明,许多逆境胁迫、生长素、种子萌发、果实成熟、脱落酸和茉莉酸合成相关的基因差异表达;甲基化组结果显示,拟南芥过表达VvMET1-1后CG和CHH位点甲基化水平分别发生了明显的上调和下调,且DNA甲基化差异区(DMR)的类型主要是CG和CHH型,因此推测VvMET1-1可能通过调控DNA甲基化水平的变化影响下游基因的表达,进而调控拟南芥的生长发育。

关键词：葡萄胚性愈伤组织 VvMET1-1 转录组测序

Gate-tunable large-scale flexible monolayer MoS_(2)devices for photodetectors and optoelectronic synapses

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Nano Research 2022年第6期15卷 5418-5424页

作者： Na Li Congli He Qinqin Wang Jianshi Tang qingtian zhang Cheng Shen Jian Tang Heyi Huang Shuopei Wang Jiawei Li Biying Huang Zheng Wei Yutuo Guo Jiahao Yuan Wei Yang Rong Yang Dongxia Shi Guangyu zhang Songshan Lake Materials Laboratory Dongguan 523808China Beijing National Laboratory for Condensed Matter Physics Key Laboratory for Nanoscale Physics and DevicesInstitute of PhysicsChinese Academy of SciencesBeijing 100190China Institute of Advanced Materials Beijing Normal UniversityBeijing 100875China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China School of Integrated Circuits Beijing Innovation Center for Future Chips(ICFC)Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084China Beijing Key Laboratory for Nanomaterials and Nanodevices Beijing 100190China

Photodetectors and optoelectronic synapses are vital for construction of artificial visual perception ***,the hardware implementations of optoelectronic-neuromorphic devices based on conventional architecture usually suffer from poor scalability,light response range,and limited ***,large-scale flexible monolayer MoS_(2)devices integrating photodetectors and optoelectronic synapses over the entire visible spectrum in one device have been realized,which can be used in photodetection,optical communication,artificial visual perception system,and optical artificial neural *** modulating gate voltages,we enable MoS_(2)-based devices to be photodetectors and also optoelectronic ***,the MoS_(2)-based optoelectronic synapses could implement many synaptic functions and neuromorphic characteristics,such as short-term memory(STM),long-term memory(LTM),paired-pulse facilitation(PPF),long-term potentiation(LTP)/long-term depression(LTD),and“learning-experience”***,an associative learning behavior(the classical conditioning Pavlov’s dog experiment)was emulated using paired stimulation of optical and voltage *** results facilitate the development of MoS_(2)-based multifunctional optoelectronic devices with a simple device structure,showing great potential for photodetection,optoelectronic neuromorphic computing,human visual systems mimicking,as well as wearable and implantable electronics.

关键词： MoS_(2) flexible devices gate-tunable photodetector optoelectronic synapse