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山峰加热效应的数值试验研究

高原气象 2008年第2期27卷 286-292页

作者：安兴琴胡隐樵吕世华左洪超中国气象科学研究院大气成分观测与服务中心北京100081 中国科学院寒区旱区环境与工程研究所西部气候环境与灾害实验室甘肃兰州730000 兰州大学大气科学学院甘肃兰州730000

已有的资料分析和理论研究表明,山峰加热效应是形成冬季兰州市白天脱地逆温的主要原因。本文利用中尺度数值模式MM5,从数值试验角度研究了兰州市白天温度场和环流场的结构特征。模拟结果表明:冬季,白天日出后的皋兰山峰相对于周围空气... 详细信息

已有的资料分析和理论研究表明,山峰加热效应是形成冬季兰州市白天脱地逆温的主要原因。本文利用中尺度数值模式MM5,从数值试验角度研究了兰州市白天温度场和环流场的结构特征。模拟结果表明:冬季,白天日出后的皋兰山峰相对于周围空气是一个热源,在环流场的配合下,皋兰山峰的暖空气向市区上空输送,与河谷温度较低的冷空气形成了白天的脱地逆温;理想"削山"试验的结果表明,山峰海拔越高的山体,加热效应越明显,山谷城市的大气逆温强度和稳定度随着山峰海拔高度的降低而减小。数值试验结果进一步验证和补充了观测和理论分析的结论。

关键词：山峰加热效应数值模拟逆温

春末黄土高原半干旱区地表能量闭合的观测研究

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冰川冻土 2010年第1期32卷 70-77页

作者：肖霞左洪超刘辉志符淙斌黄建平胡隐樵兰州大学大气科学学院甘肃兰州730000 中国科学院大气物理研究所北京100029 中国科学院寒区旱区环境与工程研究所甘肃兰州730000

利用兰州大学半干旱气候与环境监测站的连续观测数据,分析了该站的数据质量情况和黄土高原半干旱区的近地层湍流通量特征及地表能量平衡能量闭合状况.结果表明:兰州大学半干旱气候与环境监测站(SACOL)湍流通量的平均时间取30min为宜.该... 详细信息

利用兰州大学半干旱气候与环境监测站的连续观测数据,分析了该站的数据质量情况和黄土高原半干旱区的近地层湍流通量特征及地表能量平衡能量闭合状况.结果表明:兰州大学半干旱气候与环境监测站(SACOL)湍流通量的平均时间取30min为宜.该站利用EdiRe获得的湍流通量较TK2和CR5000数据自动记录器输出的湍流通量结果要好.黄土高原半干旱区近地层湍流能量与地表含水量状况明显相关,地表干燥时感热通量处于主导地位,接近于干旱区的特征;地表湿润时感热通量和潜热通量则相当,接近于湿润地区的特征.地表能量平衡分析表明,兰州大学黄土高原半干旱环境监测站观测的地表能量闭合度高达85%,与已有的观测相比,能量闭合情况属于较好水平.

关键词：数据质量控制近地层湍流通量地表能量闭合

Online Fault-Tolerant Tracking Control With Adaptive Critic for Nonaffine Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 215-227页

作者： Ding Wang Lingzhi hu Xiaoli Li Junfei qiao IEEE the School of Information Science and Technology Beijing Key Laboratory of Computational Intelligence and Intelligent SystemBeijing Laboratory of Smart Environmental Protection and Beijing Institute of Artificial Intelligence Beijing University of Technology

In this paper, a fault-tolerant-based online critic learning algorithm is developed to solve the optimal tracking control issue for nonaffine nonlinear systems with actuator ***, a novel augmented plant is constructed by fusing the system state and the reference trajectory, which aims to transform the optimal fault-tolerant tracking control design with actuator faults into the optimal regulation problem of the conventional nonlinear error system. Subsequently, in order to ensure the normal execution of the online learning algorithm, a stability criterion condition is created to obtain an initial admissible tracking policy. Then, the constructed model neural network(NN) is pretrained to recognize the system dynamics and calculate trajectory control. The critic and action NNs are constructed to output the approximate cost function and approximate tracking control,respectively. The Hamilton-Jacobi-Bellman equation of the error system is solved online through the action-critic framework. In theoretical analysis, it is proved that all concerned signals are uniformly ultimately bounded according to the Lyapunov *** tracking control law can approach the optimal tracking control within a finite approximation error. Finally, two experimental examples are conducted to indicate the effectiveness and superiority of the developed fault-tolerant tracking control scheme.

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Impact of insect-resistant GM rice on pesticide use and farmers' health in China

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Science China(Life Sciences) 2015年第5期58卷 466-471页

作者： huANG JiKun hu RuiFa qiao FangBin yin YanHong LIU huaiJu huANG ZhuRong Center for Chinese Agricultural Policy Institute of Geographical Sciences and Natural Resource Research Chinese Academy of Sciences School of Management and Economics Beijing Institute of Technology China Economics and Management Academy Central University of Finance and Economics Department of Neurology Chinese PLA General Hospital

The economic benefits of insect-resistant genetically modified(GM) crops have been well documented, but the impact of such crops and the consequent reduction in pesticide use on farmers' health remains largely unknown. Through the analysis of the data collected from the physical examination from farmers in China, we show that GM rice significantly reduces pesticide use and the resultant not only visible but also invisible adverse effects on farmers' neurological, hematological, and electrolyte system. Hence, the commercialization of GM rice is expected to improve the health of farmers in developing countries, where pesticide application is necessary to mitigate crop loss.

关键词： pesticide use farmers health genetically modified rice insect-resistance

Blockzone: A Decentralized and Trustworthy Data Plane for DNS

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Computers, Materials & Continua 2020年第11期65卷 1531-1557页

作者： Ning hu Shi yin Shen Su Xudong Jia qiao Xiang Hao Liu Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhouChina Department of Computer Science Yale UniversityNew Haven06520-8241USA Qianxin Technology Group Co. Ltd.BeijingChina

The domain name system(DNS)provides a mapping service between memorable names and numerical internet protocol addresses,and it is a critical infrastructure of the *** authenticity of DNS resolution results is crucial for ensuring the accessibility of Internet *** of supplementary specifications of protocols have been proposed to compensate for the security flaws of ***,DNS security incidents still occur *** DNS is a distributed system,for a specified domain name,only authorized authoritative servers can resolve *** servers must obtain the resolution result through a recursive or iterative resolving procedure,which renders DNS vulnerable to various attacks,such as DNS cache poisoning and distributed denial of service(DDoS)*** paper proposes a novel decentralized architecture for a DNS data plane,which is called ***,Blockzone utilizes novel mechanisms,which include on-chain authorization and off-chain storage,to implement a decentralized and trustworthy DNS data ***,in contrast to the hierarchical authentication and recursive query of traditional DNS,Blockzone implements a decentralized operation *** model significantly increases the efficiency of domain name resolution and verification and enhances the security of DNS against DDoS and cache poisoning *** addition,Blockzone is fully compatible with the traditional DNS implementation and can be incrementally deployed as a plug-in service of DNS without changing the DNS protocol or system *** Blockzone scheme can also be generalized to address security issues in other areas,such as the Internet of things and edge computing.

关键词： Network security DNS security DNS decentralization blockchain

Rattle-Type Silica Colloidal Particles Prepared by a Surface- Protected Etching Process

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Nano Research 2009年第7期2卷 583-591页

作者： qiao Zhang Jianping Ge James Goebl Yongxing hu Zhenda Lu Yadong yin Department of Chemistry University of CaliforniaRiversideCalifornia 92521USA

This paper explores the capability of the“surface-protected etching”process for the creation of rattle-type SiO_(2)@void@SiO_(2) colloidal structures featuring a mesoporous silica shell and a mesoporous movable silica *** surface-protected etching process involves stabilization of the particle surface using a polymer ligand,and then selective etching of the interior to form hollow *** this paper,this strategy has been extended to the formation of rattle-like structures by etching SiO_(2)@SiO_(2) core shell particles which are synthesized by a two-step sol gel *** key is to introduce a protecting polymer of polyvinylpyrrolidone(PVP)to the surface of both core and shell in order to tailor their relative stability against chemical *** reacting with NaOH,the outer layer silica becomes a hollow shell as only the surface layer is protected by PVP and the interior is removed,while the core remains its original size thanks to the protection of PVP on its *** process can be carried out at room temperature without the need of additional templates or complicated heterogeneous coating *** etching process also results in the rattle-type colloids having mesoscale pores with two distinct average *** our demonstration of a model drug delivery process,such mesoporous structures show an interesting two-step elution profile which is believed to be related to the unique porous rattle structures.

关键词： Silica mesoporous core-shell structure surface-protected etching drug delivery

Luminescence property and magnetic resonance imaging of Gd_(2)O_(3):Tb^(3+) nanocrystals doped with Zn^(2+),Li^(+)

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Rare Metals 2021年第8期40卷 2049-2058页

作者： Rong Fu Yan-Yan hu hui-Na qiao Chun-Lin Yang Hao yin Mei-Gui Ou College of Materials and Metallurgy University of GuizhouGuiyang550025China National Local Co-construction Engineering Laboratory for High Performance Metal Structure Material and Manufacture Technology Guiyang550025China College of Chemistry and Materials Engineering Guiyang UniversityGuiyang550003China Department of Neurosurgery Guizhou Provincial People’s HospitalGuiyang550002China

Gd_(2)O_(3):Tb^(3+) nanocrystal co-doped with Zn^(2+)and Li^(+) was prepared by the combination of polyol and solid-phase *** synthesized nanoparticles were characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),photoluminescence(PL)spectra and magnetic resonance imaging(MRI).The results revealed that both Gd_(2)O_(3):Tb^(3+)/Zn^(2+) and Gd_(2)O_(3):Tb^(3+)/Li^(+) had cubic unit structures with a spherical shape,and the fluorescence intensity of the nanoparticles reached a maximum at a doping concentration of0.050 mmol%for Zn^(2+) and 2 mol%for Li^(+),*** addition,the T_(1)/T_(2)(longitudinal/transverse relaxation time)-weighted MRI signals got enhanced due to the increased longitudinal relaxivity(r1)and transverse relaxivity(r2)after the doping by metal ***,the materials reported here can be used for fluorescence and MR bimodal imaging,as tracers and for fluorescence detections.

关键词： Gd_(2)O_(3):Tb^(3+) Zn^(2+)/Li^(+)doping Luminescent property Magnetic resonance imaging Nanomaterials

Progress in side-chain thiophene-containing polymers: synthesis, properties and applications

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Science China Chemistry 2015年第11期58卷 1641-1650页

作者： Yali qiao Xiaodong yin Chuanbing Tang Department of Chemistry and Biochemistry University of South Carolina

In contrast to conventional main-chain conjugated polymers, incorporation of electronically active conjugated oligomers into non-conjugated polymer backbones as pendant groups represents a promising alternative strategy to developing novel electroactive polymer materials that are desirable for potential applications in organic electronics. This review focuses on polymers with thiophene in the side chain and summarizes the most important synthetic approaches to these polymers, including direct controlled polymerization techniques(e.g., ATRP, ROMP, and RAFT) as well as post-polymerization modifications. Additionally, various properties and applications of these polymers are discussed.

关键词： non-conjugated polymer thiophene controlled polymerization post-polymerization modification organic electronics

Cerium oxide nanoparticles-mediated cascade catalytic chemo-photo tumor combination therapy

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Nano Research 2022年第1期15卷 333-345页

作者： Zitao hu yin Ding State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

ROS-based tumor therapy based on nanocatalytic medicine has recently been proposed for its ***,a safe and highly efficient strategy towards getting high enough ROS to kill the hypoxic cancer cells is still a great ***,we report a simple pH/H_()20_(2)-activatable,O_(2)-evolving,and ROS regulating doxorubicin(DOX)and indocyanine green(ICG)co-loading PEGylated polyaniline(PANI)coated CeOx@polyacrylic acid(PAA)nanoclusters for highly selective and optimized cancer combination *** can selectively and greatly enhance intracellular O_(2) and ROS levels in tumor region,which depends on two-step catalytic properties of nanoceria(Ce^(4+)/Ce^(3+)=3.46,neutral surface charge,mostly localize into the cytoplasm,pH 7.4-6.5,catalase-like catalytic agents convert to Ce^(4+)/Ce^(3+)=0.58,negative surface charge,mostly localize into the lysosomes,pH 5-4,oxidase-like catalytic agents,triggered by near infrared(NIA)laser irradiation).Furthermore,the protective effect of polyethylene glycol(PEG),PANI,and PAA ensure that the nanoceria can only play the role of catalase under the irradiation of NIR light arrived at the tumor ***,loading of nanoceria and ICG onto PANI greatly enhanced photo thermal effect of nanoparticles.(NPs),which is useful for killing cancer cells by relieving hypoxia and promoting cross-membrane drug *** further enhance photodynamic therapy and chemotherapy *** chemo-photo combination therapies fantastically inhibited tumor growth and prevented tumor recurrence in vivo,suggesting a smart nanotheranostic system to achieve more precise and effective therapies in O_(2)-deprived tumor tissue.

关键词： nanocatalytic medicine photodynamic therapy hypoxia cerium oxide@polyaniline combination therapy