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Phosphomolybdic acid-modified highly organized TiO2 nanotube arrays with rapid photochromic performance

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Journal of Materials Science & Technology 2019年第9期35卷 1951-1958页

作者： yuanyuan wei Bing Han Zhaojun Dong wei Feng Key Lab of Groundwater Resources and Environment Ministry of Education College of New Energy and EnvironmentJilin UniversityChangchun 130021 China Key Laboratory of Songliao Aquatic Environment Ministry of Educatio Jilin Jianzhu UniversityChangchun 130118China

TiO2 nanotube arrays were prepared by means of an electrochemical anodization technique in an organic electrolyte solution doped with polyvinyl pyrrolidone (PVP) and were subsequently modified with phosphomolybdic acid (PMoA) to obtain PMoA/TiO2 nanotube arrays. The microstructure and photochromic properties were investigated via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results indicated that the Keggin structure of PMoA and the nanotube structure of TiO2 were not destroyed, and there was a strong degree of interaction between PMoA and TiO2 at the biphasic interface with lattice interlacing during the compositing process. The XPS results further indicated that there was a change in the chemical microenvironment during the formation process of the composite, and a new charge transfer bridge was formed through the Mo-O-Ti bond. Under visible light irradiation, the colorless PMoA/TiO2 nanotube array quickly turned blue and exhibited a photochromic response together with reversible photochromism in the presence of H2O2. After visible light irradiation for 60s, the appearance of Mo^5+ species in the XPS spectra indicated a photoreduction process in accordance with a photoinduced electron transfer mechanism.

关键词： Phosphomolybdic acid TiO2 nanotube array Rapid Photochromic performance

C_(9)H_(10)O_(2):0.5ZnCl_(2)/SG as a High-Efficiency Catalyst for Desulfurization of Model Oil

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China Petroleum Processing & Petrochemical Technology 2023年第3期25卷 115-126页

作者： Li Xiuping wei yuanyuan Liu Xiaoyi Zhao Rongxiang School of Petrochemical Engineering Liaoning Petrochemical UniversityFushun 113001China Daqing Petrochemical Research Center of PetroChina Daqing 163714China

A C_(9)H_(10)O_(2):0.5ZnCl_(2)/SG catalyst was synthesized using a one-step sol-gel method with silica gel(SG)as the carrier and C_(9)H_(10)O_(2):0.5ZnCl_(2)deep eutectic solvent(DES)as active *** structure of the supported catalyst was characterized by FT-IR,XRD,SEM,and N2 adsorption-desorption,and the DES was found to have successfully permeated the SG through its *** removal of dibenzothiophene(DBT)in model diesel was studied using C_(9)H_(10)O_(2):0.5ZnCl_(2)/SG as a catalyst and H_(2)O_(2)as an *** influence of loading dose of DES,reaction temperature,catalyst dosage,O/S molar ratio,and sulfide type on the desulfurization rate was *** removal rates of DBT,4,6-dimethyldibenzothiophene(4,6-DMDBT),and benzothiophene(BT)under optimal reaction conditions were 99.4%,96%,and 78.2%,respectively.C_(9)H_(10)O_(2):0.5ZnCl_(2)/SG catalyst could be recycled five times with a little decrease of oxidative desulfurization activity,and the adsorption-oxidation desulfurization mechanism was examined.

关键词： C_(9)H_(10)O_(2):0.5ZnCl_(2)/SG sol-gel oxidative desulfurization dibenzothiophene DFT calculation

基于PSO-BP神经网络的5G基站位置确定方法

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测绘工程 2025年第1期34卷 47-52,67页

作者：杜莹韦原原蒲欢欢郑州师范学院地理与旅游学院郑州450044

5G基站位置的确定对室内定位服务和网络安全有着重要意义。首先对5G信道状态信息CSI进行Hample滤波和降维,然后构建基于粒子群优化PSO的误差反向传播BP神经网络信号损耗模型,建立5G CSI和距离的映射关系,最后基于模型预测的距离实现对5G... 详细信息

5G基站位置的确定对室内定位服务和网络安全有着重要意义。首先对5G信道状态信息CSI进行Hample滤波和降维,然后构建基于粒子群优化PSO的误差反向传播BP神经网络信号损耗模型,建立5G CSI和距离的映射关系,最后基于模型预测的距离实现对5G AP的探测。实验采用室外探测室外和室内5G AP的实测数据,结果表明,与BP神经网络相比,基于PSO-BP神经网络的距离预测值更加精确,室外探测室外和室内5G AP的精度分别达到了0.32 m和0.96 m。随着测量方向数的提升,5G AP的定位精度不断提升。当方向数达到5个时,精度提升最为显著。

关键词：信道状态信息 AP探测粒子群优化 BP神经网络

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喀斯特地区土地利用冲突识别与影响机制

水土保持研究 2025年第1期32卷 358-367页

作者：廖超明韦媛媛唐丹云子恒李宥儒南宁师范大学自然资源与测绘学院南宁530001 广西自然资源职业技术学院广西崇左532100

[目的]科学识别喀斯特地区土地利用空间冲突,揭示其影响机制,以寻求区域土地利用可持续发展路径。[方法]以典型喀斯特地貌的漓江流域为研究区,基于景观生态风险评价方法构建土地利用冲突测度模型,定量分析漓江流域1990-2020年土地利用... 详细信息

[目的]科学识别喀斯特地区土地利用空间冲突,揭示其影响机制,以寻求区域土地利用可持续发展路径。[方法]以典型喀斯特地貌的漓江流域为研究区,基于景观生态风险评价方法构建土地利用冲突测度模型,定量分析漓江流域1990-2020年土地利用冲突时空分异特征,利用地理探测器探究其影响机制。[结果](1)研究期内,漓江流域土地利用冲突水平呈缓慢下降趋势,冲突以稳定可控和基本可控为主。基本失控和严重失控占比波动下降,逐步转换为可控级别,冲突强度得到缓解。(2)土地利用冲突具有“中部高四周低”的带状空间格局,且空间异质性显著。冲突高值区集聚在流域各区县主城区和漓江主要水系邻近区域,低值区则分布在四周山区林地地带。(3)DEM、坡度、地形起伏度、NDVI、路网密度是漓江流域土地利用冲突的主要影响因素。[结论]漓江流域土地利用冲突变化明显,失控地区逐渐转换为可控级别,未来漓江流域应持续推进生态保护和修复提升工作,稳定区域土地利用结构,实现土地资源的可持续利用。

关键词：土地利用冲突时空演变空间自相关驱动机制漓江流域

Spatial–temporal variations of NDVI and its response to climate in China from 2001 to 2020

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International Journal of Digital Earth 2022年第1期15卷 1463-1484页

作者： yuanyuan wei Shougang Sun Dong Liang Zhaohong Jia School of Internet Anhui UniversityHefeiPeople’s Republic of China National Engineering Research Center for Agro-Ecological Big Data Analysis & Application Anhui UniversityHefeiPeople’s Republic of China School of Computer Science and Technology Anhui UniversityHefeiPeople’s Republic of China

Vegetation plays an important role in global or regional environmental *** this study,the spatial–temporal variations of NDVI and its response to climate in China and its seven sub-regions were investigated based on MODIS NDVI data,ERA5-land precipitation(PRE)and temperature(TEM)data from 2001 to *** inter-annual growth rate of NDVI in China was 0.0021/yr in the past 20 *** inter-annual growth rates of NDVI in seven sub-regions had significant differences at regional or seasonal *** ratio of improved vegetation area to the total studied area reached about 70%.In summer,vegetation degradation was concentrated in East China and Southwest *** vegetation in Central China and South China improved more obviously in autumn than in the other *** vegetation of Northeast China had a remarkable degradation in autumn and winter,especially in *** influence degree of PRE(q=0.54,P<0.01)was greater than that of TEM(q=0.27,P<0.01)in the control of the spatial distribution of *** interaction influence degree q of PRE∩TEM was about 0.71 in the last 20 ***,the PRE and TEM played different roles in vegetation growth in seven sub-regions.

关键词： NDVI spatial–temporal variations climate change MK test Geodetector

The transfer line design for the HEPS project

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Radiation Detection Technology and Methods 2020年第4期4卷 440-447页

作者： yuanyuan wei Yuemei Peng Gang Xu yuanyuan Guo Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

Purpose The high energy photon source(HEPS),a 6-GeV synchrotron radiation facility with ultralow emittance,is under construction in *** transfer lines are designed for *** low-energy transfer line is used to deliver the 500 MeV beam provided by the linac to the *** high-energy transfer lines are used to connect the booster and the storage ring to realize beam accumulation in the booster at 6 *** The design of the transfer lines is closely related to the layout and optics design of the storage ring,booster and *** on the physics design of the storage ring,booster and linac,the design of the transfer lines has been *** and conclusion In this paper,the considerations and design of the latest lattice of transfer lines are *** design satisfies the requirements of the high efficiency transmission and injection.

关键词： HEPS Transfer lines Optics Error study

Variable rate fertilization system with adjustable active feed-roll length

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International Journal of Agricultural and Biological Engineering 2015年第4期8卷 19-26页

作者： Su Ning Xu Taosheng Song Liangtu Wang Rujing wei yuanyuan Department of Automation University of Science and Technology of ChinaHefei 230026China Institute of Intelligent Machines Chinese Academy of SciencesHefei 230031China

This paper presented a novel variable rate fertilization system based on the method of adjusting the active feed-roll length of a fluted *** feasibility of this method was discussed using analysis of the fluted roller *** seed drill produced by Kuhn Company(France),which could sow and fertilize simultaneously,was used as a test platform to implement the mechanical structure of variable rate *** design methods for the variable rate fertilization mechanical structure and actuator were introduced in detail.A low-cost and stable embedded support decision subsystem and corresponding software were *** support decision subsystem is based on grid *** grid field cell contains information about corresponding spatial position and fertilizer application rate.A SpatiaLite database was employed to solve the spatial location search and spatial data *** were conducted to evaluate the fertilization uniformity and dynamic response *** average value of coefficient of variation is 8.4%in five different active feed-roll lengths which reflects good *** dynamic response times for the adjustment of variable rate fertilization system from 204 kg/hm^(2) to 319 kg/hm^(2) and 319 kg/hm^(2) to 204 kg/hm^(2) are about 4.2 *** results suggest that the variable rate fertilization system performs well in dynamic adjustment and stability.

关键词： precision agriculture variable rate fertilization fluted roller active feed-roll length servo drive embedded system

Tumor microenvironment-activatable neuropeptide-drug conjugates enhanced tumor penetration and inhibition via multiple delivery pathways and calcium deposition

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Chinese Chemical Letters 2024年第4期35卷 292-297页

作者： Yi Cao Xiaojiao Ge yuanyuan wei Lulu He Aiguo Wu Juan Li Ningbo Key Laboratory of Biomedical Imaging Probe Materials and Technology Zhejiang International Cooperation Base of Biomedical Materials Technology and ApplicationChinese Academy of Sciences(CAS)Key Laboratory of Magnetic Materials and DevicesNingbo Cixi Institute of Biomedical EngineeringZhejiang Engineering Research Center for Biomedical MaterialsNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516000China

Peptide-drug conjugates have achieved considerable development and application as a novel strategy for targeted delivery of anticancer drugs. Bioactive peptides induced calcium deposition can irreversibly assist inhibition of tumors. However, active regulation of calcium level through signal transduction of bioactive substances has not been reported yet. In this study, novel neuropeptide-doxorubicin conjugates(NP-DOX) with lysosome-specific acid response were described for neuropeptide Y_1 receptor(Y_1R)-overexpressed triple-negative breast cancer. The delivery mechanism of NP-DOX was clarified that diverse pathways were involved, including intracellular and intercellular transport. Importantly, up-regulation of Y_1 R-mediated intracellular calcium level via second messenger inositol triphosphate was presented in NP-DOX treated MDA-MB-231 cells. In vivo antitumor efficacy demonstrated that NP-DOX showed less organ toxicity and enhanced tumor inhibition benefited from its controlled release and Y_1R-mediated calcium deposition, compared with free DOX. This bioconjugate is a proof-of-concept confirming that neuropeptide-mediated control of signaling responses in neuropeptide-drug conjugates enables great potential for further applications in tumor chemotherapy.

关键词： Neuropeptide-drug conjugate Tumor penetration Calcium deposition Tumor inhibition Triple-negative breast cancer

Research on the slow orbit feedback of BEPCⅡusing machine learning

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Radiation Detection Technology and Methods 2022年第2期6卷 179-186页

作者： Yu Bai yuanyuan wei weibin Liu Gang Xu Jiuqing Wang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Background:Long-term orbit stability is a key performance indicator in synchrotron radiation facilities and colliders nowa-days,in which the orbit correction and corresponding slow orbit feedback system are *** method of orbit correction uses response matrix based on SVD algorithm,which becomes less effective after a long operation due to the fact that response matrix measurements cannot be taken during normal ***:The purpose of this paper is to integrate machine learning model into the slow orbit feedback process and to automatically update the model online to better correct the orbit ***:In this paper,we propose a method for slow orbit feedback of storage ring based on machine *** the neural networks by using online data sets,which can establish the mapping relation between BPMs and correctors,and being updated automatically,without using extra time to remeasure the response ***:The experiments in this paper are all conducted and verified in the upgrading project of Beijing Electron-Positron *** the way of learning automatically,the updated neutral network is closer to the real machine model,and the orbit after correction shows a smaller fluctuation relative to the golden ***:Using the online data sets which reflect the response of orbit to correctors in real time to update the neural network can increase the orbit stability.

关键词： Orbit correction Machine learning Slow orbit feedback Learning automatically