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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 46-56页

作者： Qiu Shiming wang shengjie School of Chemistry and Chemical Engineering Guangxi Minzu Normal UniversityChongzuo 532200GuangxiChina Guangxi Key Laboratory for High-value Utilization of Manganese Resources Chongzuo 532200GuangxiChina

The Cu/ZnO catalyst formed upon the calcination of aurichalcite has a uniform distribution of ZnO,which can delay the sintering of Cu species at high *** this study,aurichalcite possessing a nearly pure phase was prepared using the ammonium complex dissociation precipitation method,and the effect of calcination temperature on the structure and surface properties of the derived Cu/ZnO catalyst was *** results show that the calcination temperature determines the particle size and crystallization degree of the Cu/ZnO catalyst and the surface properties of the corresponding copper oxide and reduced ***-temperature calcination is more conducive to reducing the particle size of the Cu/ZnO catalyst,increasing the specific surface area,and generating abundant defect characteristics on the surface,which is key to obtaining highly dispersed copper and copper-specific surface area catalysts by subsequent ***,the Cu/ZnO catalyst derived using a 300℃or 400℃calcination proved to have a higher specific activity per gram of copper than a commercial Cu/Zn/Al *** discovery in this study opens up a new method for the convenient preparation of a high-temperature resistant Cu/Zn methanol reforming catalyst.

关键词： methanol reforming copper zinc oxide lattice defect

Multiple Targets Localization Algorithm Based on Covariance Matrix Sparse Representation and Bayesian Learning

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Journal of Beijing Institute of Technology 2024年第2期33卷 119-129页

作者： Jichuan Liu Xiangzhi Meng shengjie wang School of Electronic Engineering Xidian UniversityXi’an 710071China Hebei Key Laboratory of Electromagnetic Spectrum Cognition and Control Shijiazhuang 050081China

The multi-source passive localization problem is a problem of great interest in signal pro-cessing with many *** this paper,a sparse representation model based on covariance matrix is constructed for the long-range localization scenario,and a sparse Bayesian learning algo-rithm based on Laplace prior of signal covariance is developed for the base mismatch problem caused by target deviation from the initial point *** adaptive grid sparse Bayesian learning targets localization(AGSBL)algorithm is *** AGSBL algorithm implements a covari-ance-based sparse signal reconstruction and grid adaptive localization dictionary ***-tion results show that the AGSBL algorithm outperforms the traditional compressed-aware localiza-tion algorithm for different signal-to-noise ratios and different number of targets in long-range scenes.

关键词： grid adaptive model Bayesian learning multi-source localization

Linkage between precipitation isotopes and water vapor sources in the monsoon margin:Evidence from arid areas of Northwest China

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Journal of Arid Land 2024年第3期16卷 355-372页

作者： CHEN Fenli ZHANG Qiuyan wang shengjie CHEN Jufan GAO Minyan Mohd Aadil BHAT College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730000China Key Laboratory of Resource Environment and Sustainable Development of Oasis of Gansu Province Northwest Normal UniversityLanzhou 730000China School of Ocean and Earth Science Tongji UniversityShanghai 200092China

The isotope composition in precipitation has been widely considered as a tracer of monsoon *** with the coastal region,the monsoon margin usually has limited precipitation with large fluctuation and is usually sensitive to climate *** water resource management in the monsoon margin should be better planned by understanding the composition of precipitation isotope and its influencing *** this study,the precipitation samples were collected at five sampling sites(Baiyin City,Kongtong District,Maqu County,Wudu District,and Yinchuan City)of the monsoon margin in the northwest of China in 2022 to analyze the characteristics of stable hydrogen(δD)and oxygen(δ18O)*** analyzed the impact of meteorological factors(temperature,precipitation,and relative humidity)on the composition of precipitation isotope at daily level by regression analysis,utilized the Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)-based backward trajectory model to simulate the air mass trajectory of precipitation events,and adopted the potential source contribution function(PSCF)and concentration weighted trajectory(CWT)to analyze the water vapor *** results showed that compared with the global meteoric water line(GMWL),the slope of the local meteoric water line(LMWL;δD=7.34δ^(18)O-1.16)was lower,indicating the existence of strong regional evaporation in the study *** significantly contributed toδ18O value,while relative humidity had a significant negative effect onδ18O *** the backward trajectory analysis,we found eight primary locations that were responsible for the water vapor sources of precipitation in the study area,of which moisture from the Indian Ocean to South China Sea(ITSC)and the western continental(CW)had the greatest influence on precipitation in the study *** hydrogen and oxygen isotopes in precipitation are significantly influenced by the sources and transportation paths of air *** addition,the r

关键词： water vapor monsoon margin stable water isotope transport trajectory air mass d-excess δ18O δD

Comparison of isotope-based linear and Bayesian mixing models in determining moisture recycling ratio

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Journal of Arid Land 2024年第6期16卷 739-751页

作者： XIAO Yanqiong wang Liwei wang shengjie Kei YOSHIMURA SHI Yudong LI Xiaofei Athanassios A ARGIRIOU ZHANG Mingjun Key Laboratory of Resource Environment and Sustainable Development of Oasis of Gansu Province College of Geography and Environmental ScienceNorthwest Normal UniversityLanzhou 730070China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Atmosphere and Ocean Research Institute University of TokyoKashiwa 277-8568Japan School of Environmental Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China Laboratory of Atmospheric Physics Department of PhysicsUniversity of PatrasPatras GR-26500Greece

Stable water isotopes are natural tracers quantifying the contribution of moisture recycling to local precipitation,i.e.,the moisture recycling ratio,but various isotope-based models usually lead to different results,which affects the accuracy of local moisture *** this study,a total of 18 stations from four typical areas in China were selected to compare the performance of isotope-based linear and Bayesian mixing models and to determine local moisture recycling *** the three vapor sources including advection,transpiration,and surface evaporation,the advection vapor usually played a dominant role,and the contribution of surface evaporation was less than that of *** the abnormal values were ignored,the arithmetic averages of differences between isotope-based linear and the Bayesian mixing models were 0.9%for transpiration,0.2%for surface evaporation,and–1.1%for advection,respectively,and the medians were 0.5%,0.2%,and–0.8%,*** importance of transpiration was slightly less for most cases when the Bayesian mixing model was applied,and the contribution of advection was relatively *** Bayesian mixing model was found to perform better in determining an efficient solution since linear model sometimes resulted in negative contribution *** test with two isotope scenarios indicated that the Bayesian model had a relatively low sensitivity to the changes in isotope input,and it was important to accurately estimate the isotopes in precipitation ***,the Bayesian mixing model should be recommended instead of a linear *** findings are useful for understanding the performance of isotope-based linear and Bayesian mixing models under various climate backgrounds.

关键词： moisture recycling stable water isotope linear mixing model Bayesian mixing model China

LncRNA CCRR maintains Ca^(2+)homeostasis against myocardial infarction through the FTO-SERCA2a pathway

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Science China(Life Sciences) 2024年第8期67卷 1601-1619页

作者： Hua Yang Lina Xuan shengjie wang Huishan Luo Xiaomeng Duan Jianjun Guo Shijia Cui Jieru Xin Junwei Hao Xiufang Li Jun Chen Feihan Sun Xiaolin Hu Siyun Li Ying Zhang Lei Jiao Baofeng Yang Lihua Sun Department of Pharmacology Harbin Medical University(State Key Laboratory of Frigid Zone Cardiovascular Diseasethe State-Province Key Laboratories of Biomedicine-Pharmaceutics of ChinaKey Laboratory of Cardiovascular ResearchMinistry of EducationJoint International Research Laboratory of Cardiovascular Medicine ResearchMinistry of EducationChina)College of PharmacyHarbin Medical UniversityHarbin 150081China

Cardiac conduction regulatory RNA(CCRR)has been documented as an antiarrhythmic lncRNA in our earlier *** study aimed to evaluate the effects of CCRR on SERCA2a and the associated Ca^(2+)homeostasis in myocardial infarction(MI).Overexpression of CCRR via AAV9-mediated delivery not only partially reversed ischemia-induced contractile dysfunction but also alleviated abnormal Ca^(2+)homeostasis and reduced the heightened methylation level of SERCA2a following *** effects were also observed in CCRR overexpressing transgenic mice.A conserved sequence domain of CCRR mimicked the protective function observed with the full ***,silencing CCRR in healthy mice led to intracellular Ca^(2+)overloading of *** increased SERCA2a protein stability by upregulating FTO *** direct interaction between CCRR and FTO protein was characterized by RNA-binding protein immunoprecipitation(RIP)analysis and RNA pulldown *** of NFATc3 was identified as an upstream mechanism responsible for CCRR downregulation in *** study demonstrates that CCRR is a protective lncRNA that acts by maintaining the function of FTO,thereby reducing the m^(6)A RNA methylation level of SERCA2a,ultimately preserving calcium homeostasis for myocardial contractile function in ***,CCRR may be considered a promising therapeutic strategy with a beneficial role in cardiac pathology.

关键词： CCRR calcium homeostasis FTO myocardial infarction SERCA2a

Ultrafast photoexcitation dynamics behavior of hydrogen-bonded polyfluorenol

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Chinese Chemical Letters 2024年第1期35卷 486-491页

作者： Man Xu Chuanxin Wei Yunlong Zhang Hao Li Jingyao Ma Jinyi Lin shengjie wang Wei Xue Qi Wei Linghai Xie Wei Huang State Key Laboratory of Organic Electronics and Information Displays&School of Chemistry and Life Sciences&Institute of Advanced Materials(IAM) Nanjing University of Posts&TelecommunicationsNanjing 210023China Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech University(NanjingTech)Nanjing 211816China Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SIFE)&Shaanxi Institute of Biomedical Materials and Engineering(SIBME)Northwestern Polytechnical UniversityXi’an 710072China

Exciton behavior is crucial to the exploitation of light-emitting conjugated polymer(LCPs)for optoelectronic *** excitons are easily trapped by the intrinsically defect ***,we set a polyfluorenol(PPFOH)as an example to systematically investigate its photophysical behavior to check the role of defect structures in *** to time-resolved photoluminescence analysis,the feature emission peaks from individual chain of PPFOH in diluted DMF solution is effectively avoided the influence of fluorenone formation,but the residual green-band emission at 550nm is easily observed in the PL spectra of PPFOH dilute toluene solution obtained delay 1.5 ns,confirmed the formation of“guest”physical aggregation-induced defect ***,efficient and ultrafast energy transfer from individual chain to defect structure is observed in PPFOH ***,the efficient energy transfer happened for the film obtained from DMF solution(200 ps)than those of toluene ones(600 ps).Meanwhile,compared to relatively stable green-band emission in PPFOH film from toluene solution,red-shifted emission peak(11 nm)of PPFOH film from DMF solutions exposed to saturated DNT vapor also confirmed their different aggregation-induced green-band ***,this aggregation defect structures are influenced on the photophysical property of LCPs in solid states.

关键词： Photoexcitation dynamics Polyfluorenol Aggregation behavior Energy transfer Exciton migration

基于可解释机器学习模型的电信行业客户流失预测研究

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电信科学 2024年第7期40卷 121-133页

作者：王圣节张庆红新疆财经大学统计与数据科学学院新疆乌鲁木齐830012

在电信行业中,客户流失的准确预测对于相关企业维持市场竞争力和增加收益至关重要。为此提出一个结合CatBoost算法和SHAP(shapley additive explanations)模型的客户流失预测框架,旨在提高预测的准确性,同时增强模型的可解释性。利用新... 详细信息

在电信行业中,客户流失的准确预测对于相关企业维持市场竞争力和增加收益至关重要。为此提出一个结合CatBoost算法和SHAP(shapley additive explanations)模型的客户流失预测框架,旨在提高预测的准确性,同时增强模型的可解释性。利用新疆某通信公司的实际营业数据,通过数据预处理及特征工程,构建预测模型,选取5种主要关键性能指标评估模型性能。实验结果显示,所提出模型在选取的评价指标上均优于当前主流机器学习预测模型。最后引入SHAP框架增强模型可解释性,揭示影响客户流失的关键因素,并提供具体的因素影响程度,为电信企业制定针对性的客户保留策略提供了科学依据。

关键词：机器学习 CatBoost算法 SHAP 预测模型电信行业

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蒸氨法制备绿铜锌矿晶体的工艺研究

人工晶体学报 2024年第4期53卷 701-706页

作者：邱诗铭闫冠杰李春流王胜杰广西民族师范学院崇左532200 广西锰资源高值化利用重点实验室崇左532200 崇左市锰资源综合利用技术重点实验室崇左532200 南方锰业集团有限责任公司崇左分公司崇左532200

本文以碱式碳酸铜、碱式碳酸锌和浓氨水为原料,采用蒸氨法合成绿铜锌矿。通过XRD、TGA、SEM-Mapping、FT-IR等表征手段,研究工艺条件对绿铜锌矿晶体结构的影响规律。实验表明,铜浓度为120 g/L,铜锌摩尔比分别为3∶2、1∶1、2∶3时,沉淀... 详细信息

本文以碱式碳酸铜、碱式碳酸锌和浓氨水为原料,采用蒸氨法合成绿铜锌矿。通过XRD、TGA、SEM-Mapping、FT-IR等表征手段,研究工艺条件对绿铜锌矿晶体结构的影响规律。实验表明,铜浓度为120 g/L,铜锌摩尔比分别为3∶2、1∶1、2∶3时,沉淀产物中的晶体由绿铜锌矿与孔雀石组成,且孔雀石数量随铜锌摩尔比的降低而减少。当铜锌摩尔比为2∶3,铜浓度由120 g/L降低至80 g/L时,孔雀石晶体的数量进一步减少。在铜锌摩尔比为2∶3,铜浓度为80 g/L的条件下,沉淀得到单一物相的绿铜锌矿晶体,为蒸氨法控制合成绿铜锌矿提供了数据支撑。

关键词：蒸氨法工艺条件绿铜锌矿孔雀石晶体结构

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不同乙炔炭黑对涂炭铝箔性能的影响

电源技术 2024年第9期48卷 1794-1799页

作者：韦宗辰王胜杰邱诗铭广西民族师范学院化学与生物工程学院广西崇左532200 广西锰资源高值化利用重点实验室广西崇左532200

采用三种不同的乙炔炭黑为原材料,通过扫描电子显微镜(SEM)、比表面积(BET)、激光粒度仪等对乙炔炭黑进行表征与分析。测试加入不同乙炔炭黑的浆料的稳定性和粘度变化,通过凹版涂布工序制得涂炭铝箔并进行电性能测试分析,评估三种乙炔... 详细信息

采用三种不同的乙炔炭黑为原材料,通过扫描电子显微镜(SEM)、比表面积(BET)、激光粒度仪等对乙炔炭黑进行表征与分析。测试加入不同乙炔炭黑的浆料的稳定性和粘度变化,通过凹版涂布工序制得涂炭铝箔并进行电性能测试分析,评估三种乙炔炭黑对涂炭铝箔性能的影响。结果表明:实验室所用的乙炔炭黑颗粒团聚粒度分布在8μm左右,比表面积约为60 m^(2)/g,SP-009和Li-2060表面粗糙,具有蓬松的孔状结构,有利于活性物质嵌入,增大活性物质与箔材的接触面积。配制成浆料后,SP-009在三者中沉降最少,分散性和稳定性较好。SP-009的涂炭铝箔电阻率最小且较为集中,均值为1.95 mΩ,电阻越小,性能最优。将三者制成的电池循环性能进行对比,SP-009的电池经过循环100次后容量保持率最高,为84.46%。SP-009乙炔炭黑性能较好,提高了浆料的稳定性和涂炭铝箔的导电性能。

关键词：乙炔炭黑导电性涂炭铝箔

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基于CKF的大型拖拉机状态参数估计研究

中国农机化学报 2024年第4期45卷 117-122,154页

作者：魏国俊王鸿翔王圣杰王振雨肖茂华江苏省农业机械试验鉴定站南京市210017 江苏电子信息职业学院江苏淮安223003 江苏悦达智能农业装备有限公司江苏盐城224007 南京农业大学工学院南京市210031

拖拉机运行状态的准确识别与估计是其安全行驶和平稳控制的重要依据。针对大型拖拉机状态参数的估计复杂、精确度不高等问题,建立大型拖拉机整车三自由度仿真模型,其中包含Dugoff轮胎模型,提出基于容积卡尔曼滤波理论的大型拖拉机状态... 详细信息

拖拉机运行状态的准确识别与估计是其安全行驶和平稳控制的重要依据。针对大型拖拉机状态参数的估计复杂、精确度不高等问题,建立大型拖拉机整车三自由度仿真模型,其中包含Dugoff轮胎模型,提出基于容积卡尔曼滤波理论的大型拖拉机状态参数估计算法,并对大型拖拉机的行驶参数进行估计,包含纵向速度、侧向速度、质心侧偏角、横摆角速度。利用Matlab软件仿真验证,在双移线路面附着系数为0.8和0.6的工况下,对比仿真的状态参数和算法估计的数值。结果表明,拖拉机横摆角速度、质心侧偏角和纵向速度仿真值与真实值的误差分别为0.1、0.2、0.4,验证基于容积卡尔曼滤波算法对大型拖拉机状态参数估计的可行性和准确性,为大型拖拉机的稳定性控制等提供借鉴和参考。

关键词：大型拖拉机非线性动力学容积卡尔曼滤波状态参数 Dugoff轮胎模型

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