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Heavy Precipitation over the jing–jin–ji Region in Early October: What Controls Its Interannual Variability?

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Journal of Meteorological Research 2022年第4期36卷 586-600页

作者： jing FENG Tim LI ji WANG Linna ZHANG Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate andEnvironmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC–FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China Beijing Meteorological Information Center China Meteorological AdministrationBeijing 100089China International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonoluluHawaii 96822USA Beijing Municipal Climate Center Beijing 100089China Beijing Meteorological Observatory Beijing 100089China

Heavy regional precipitation(HRP)over Beijing,Tianjin,and Hebei Province(the jing–jin–ji region or JJJ)in early October(1–10 October)is a high-impact climate event because of travel and outdoor activities by exceptionally large population during the Chinese National Day Holidays(CNDH).What causes the year-to-year variation of the HRP during early October is investigated through an observational *** is found that the HRP arises from moisture transport by southerly anomalies to the west of an anomalous low-level anticyclone over the subtropical northwestern Pacific(SNWP).Sensitivity numerical experiments reveal that the low-level anticyclonic anomaly is caused by a dipole heating pattern over tropical western and central Pacific associated with a La Niña-like SST anomaly(SSTA)pattern in the Pacific and by a negative heating anomaly over North *** latter connects the SNWP anticyclone through a Rossby wave *** ascent associated with a positive heating anomaly over the tropical western Pacific may strengthen the local Hadley Cell,contributing to maintenance of the low-level anomalous anticyclone over SNWP and extending westwards of the western Pacific subtropical high(WPSH).Therefore,both the tropical Pacific and midlatitude heating signals over North Europe may be potential predictors for HRP forecast in the JJJ region in early October.

关键词： heavy regional precipitation(HRP)in jing–jin–ji(JJJ) Beijing Tianjin and Hebei Province water vapor(WV)transport Rossby wave train diabatic heating anomalies La Niña-like SST anomaly

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浙江省高职院校现代学徒制政策执行效果评价

职业技术 2025年第1期24卷 39-46页

作者：季青媛浙江艺术职业学院杭州310053

浙江加快改造提升传统产业,大力培育战略性新兴产业与未来产业,打造新技术、新产业、新业态、新模式“四新”经济。为解决企业转型升级所引致的人才结构性供需矛盾问题,职业院校积极深化产教融合,推进现代学徒制,全面提升技术技能人才... 详细信息

浙江加快改造提升传统产业,大力培育战略性新兴产业与未来产业,打造新技术、新产业、新业态、新模式“四新”经济。为解决企业转型升级所引致的人才结构性供需矛盾问题,职业院校积极深化产教融合,推进现代学徒制,全面提升技术技能人才培养能力和水平。基于史密斯政策执行理论的四个维度,分析浙江省现代学徒制政策执行的影响因素,发现政策执行存在现代学徒制政策协同作用有待提升,企业主体地位有待充分显现,学生学徒双重身份保障不力,政策执行环境有待优化等问题。基于此,提出应加强政策顶层设计,强化执行机构能力,把控学徒培养质量,提升目标群体政策认同度,营造良好政策执行生态。

关键词：现代学徒制政策执行效果评价

Mechanism Study on the Effect of Retarder on Polyurethane Setting Time Based on Molecular Simulation

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 224-231页

作者：吴宇轩徐文远 YU Tianlai ji Yongcheng School of Civil Engineering Northeast Forestry University

This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal *** mechanism by which phosphate ester affects the setting time of polyurethane was further investigated using molecular dynamics *** transform infrared spectroscopy was also employed to systematically study the physical and chemical interactions between phosphate esters and polyurethane *** results demonstrate that a 1% concentration of phosphate ester provides the most effective retarding effect with minimal impact on the strength of *** phosphate ester is added to the B component of the two-component polyurethane system,its interaction energy with component A decreases,as do the diffusion coefficient and aggregation degree of component B on the surface of component *** reduction in interaction slows the setting ***,the addition of phosphate ester to polyurethane leads to the disappearance or weakening of functional groups,indicating competitive interactions within the phosphate ester components that inhibit the reaction rate.

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Distributed optimal consensus control for multiagent systems based on event-triggered and prioritized experience replay strategies

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Science China(Information Sciences) 2025年第1期 306-321页

作者： Cuijuan ZHANG Lianghao ji Shasha YANG Xing GUO Huaqing LI Chongqing Key Laboratory of Image Cognition Chongqing University of Posts and Telecommunications Key Laboratory of Intelligent Perception and Computing of Anhui Province Anqing Normal University College of Electronic and Information Engineering Southwest University

This study uses event-triggered(ET) and reinforcement learning methods to investigate the optimal consensus control problem for cooperative-competitive multiagent systems. It proposes a novel distributed ET control strategy, which relies on a prioritized experience replay(PER) policy. This strategy not only conserves communication resources but also ensures acceptable system performance. To implement the proposed method, actor-critic(AC) dual-structured neural networks(NNs) are used to approximate the value function and control policy. In the AC NNs, the weight estimates for the NNs are updated at the moment of event triggering, resulting in a nonperiodic weight adjustment pattern. This approach decreases the computational cost in comparison with the traditional ET mechanism. The PER-based ET mechanism makes full use of valid historical data and effectively establishes a balance between system performance and communication resource ***, it does not require the following two conditions in most existing studies:(1) requirement of the system dynamics model to be known, and(2) persistent excitation. In addition, Zeno behavior is excluded from this study. Finally, a simulation is conducted to confirm the validity of the suggested approach.

关键词：

Self-Triggered Impulsive Control for Nonlinear Stochastic Systems

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 264-266页

作者： Tao Zhan Yi ji Yabin Gao Hongyi Li Yuanqing Xia the School of Mathematics and Statistics Southwest University the School of Astronautics Harbin Institute of Technology IEEE the College of Electronic and Information Engineering Southwest University Zhongyuan University of Technology the School of Automation Beijing Institute of Technology

Dear Editor,This letter deals with the stabilization problem of nonlinear stochastic systems via self-triggered impulsive control(STIC), where the timing of impulsive control actions is not dependent on continuous state monitoring. In contrast to the existing self-triggered control method, novel self-triggered mechanism(STM) is proposed by incorporating a waiting time for stabilizing impulses. This allows for direct prediction of the next impulsive instant.

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袁大滩煤矿主斜井带式输送机提能改造设计

煤矿机械 2025年第1期46卷 143-146页

作者：姬红刚中煤科工集团北京华宇工程有限公司西安分公司西安710075

以袁大滩煤矿主斜井带式输送机为例,介绍了主斜井带式输送机提能改造的设计特点:采用低噪声节能托辊和低滚阻节能型输送带来降低运行阻力,采用工期最短的改造方案来减少矿井停产造成的经济损失。改造的思路和方案,可供相关煤矿和设计人... 详细信息

以袁大滩煤矿主斜井带式输送机为例,介绍了主斜井带式输送机提能改造的设计特点:采用低噪声节能托辊和低滚阻节能型输送带来降低运行阻力,采用工期最短的改造方案来减少矿井停产造成的经济损失。改造的思路和方案,可供相关煤矿和设计人员参考借鉴。

关键词：煤矿主斜井带式输送机提能改造节能

Synthesis and Crystal Structure of 4-Salicylimine-3, 5-bis(2-hydroxyphenyl)-1, 2, 4-triazole ji Bao-Minga

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Chinese Journal of Structural Chemistry 2002年第3期21卷 252-255页

作者： ji Bao-Ming DU Chen-Xia ZHU Yu WANG Yang Department of Chemistry Luoyang Teacher's College Luoyang 471022 Department of Chemistry Zhengzhou University Zhengzhou 450052 School of Pharmacy Fudan University 上海 200032

The title compound, 4-salicylimine-3, 5-bis(2-hydroxyphenyl)-1, 2, 4-triazole, was obtained by the condensation reaction of 4-amino-3, 5-bis(2-hydroxyphenyl)-1, 2, 4-triazole with salicylaldehyde in methanol. The crystal structure (C21H16N4O3, Mr = 372.38) belongs to monoclinic system, space group P21/n with a = 10.507(2), b = 16.878(3), c = 11.199(2) ? = 110.86(3), V = 1855.9(6) ?, Z = 4, Dc = 1.333 g/cm3, F(000) = 776, (MoK? = 0.092 mm-1, R = 0.0552 and wR = 0.1095 for 1920 reflections ( I > 2.0(I) ). The analytical results of crystal structure show that there are two different non-covalent interactions in the compound. One is hydrogen bond, and the other p-p stacking interaction. These two types of non-covalent interactions play an important role in the packing of crystal.

关键词： triazole hydrogen bond crystal structure stacking interaction

一种基于柱面镜聚焦系统的高灵敏度全谱光谱仪

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光谱学与光谱分析 2025年第1期45卷 222-230页

作者：陈吉文陈作儿赵迎北方工业大学电气与控制工程学院北京100144

很多元素的最灵敏谱线主要分布在紫外波段。一些常被作为检测对象的重要元素,例如C、P和S,其谱线甚至位于200 nm以下的真空紫外波段。然而真空紫外波段内的辐射极易受空气吸收而无法在空气中传输。因此为了适用于紫外波段各谱线的检测,... 详细信息

很多元素的最灵敏谱线主要分布在紫外波段。一些常被作为检测对象的重要元素,例如C、P和S,其谱线甚至位于200 nm以下的真空紫外波段。然而真空紫外波段内的辐射极易受空气吸收而无法在空气中传输。因此为了适用于紫外波段各谱线的检测,常使用光程短、系统精简的罗兰圆光学系统作为光谱仪的色散系统,并且在进行检测分析时,还需对设备腔体内部建立相对真空的环境进行实验,进而减小实验环境对真空紫外波段内各谱线强度的削弱作用。然而即使在该条件下,P和S这两种元素在真空紫外波段的谱线灵敏度仍然较弱。为此为了实现真空紫外波段范围内的高灵敏度,本研究在距离像面前30 mm处位置设计了一个柱面镜聚焦系统。其采用了材料为CaF_(2)、中心厚度为5 mm以及弧矢面曲率半径为22.06 mm的柱面镜作为核心部件。并利用仿真软件Zemax对设计的光学系统进行仿真与优化,以及从非序列模式下的辐射照度仿真结果可知,柱面镜聚焦系统在几乎不影响分辨率的情况下对各波长成像灵敏度有较大的提升。最后以中低合金钢为检测样品,使用电火花激发光源对样品中各元素在紫外波段内的各谱线进行激发,进而验证光谱仪的各项性能:通过一次拟合、参比拟合以及二次拟合,建立每个元素谱峰强度和实际含量之间的数学模型,并算得各元素的拟合优度R^(2)均在0.99以上;柱面镜聚焦系统显著提高了设备在真空紫外波段的灵敏度,响应提高了1倍以上。实验结果表明,柱面镜聚焦系统的设计方法对于提升罗兰圆色散系统的灵敏度具有一定的参考价值。

关键词：紫外光谱罗兰圆光学系统柱面镜灵敏度拟合优度

Use of compositional and combinatorial nanomaterial libraries for biological studies

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Science Bulletin 2016年第10期61卷 755-771页

作者： Zhaoxia ji Center for Environmental Implications of Nanotechnology California Nano Systems Institute University of California

Abstract The rapid development and production of nanomaterials has created some concerns about their potential hazard on the environment, human health and safety. However, since the list of materials that may gen- erate such concerns is very long, it is impossible to test them all. It is therefore usually recommended to use some small compositional nanomaterial libraries to perform ini- tial toxicity screening, based on which combinatorial libraries are then introduced for more in-depth studies. All nanomaterials in the compositional and combinatorial libraries must be rigorously characterized before any bio- logical studies. In this review, several major categories of physicochemical properties that must be characterized are discussed, along with different analytical techniques that are commonly used. Some case studies from the University of California Center for Environmental Implications of Nanotechnology are also chosen to demonstrate the effec- tive use of compositional and combinatorial nanomaterials libraries to identify the role of some key physicochemical properties and to establish true quantitative structure-ac- tivity relationships. Examples on how to use the knowledge generated from those studies to design safer nanomaterials for improved biological applications are also presented.

关键词： Nanomaterial Physicochemical property Characterization Nanotechnology Toxicity Compositional library Combinatoriallibrary