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Static Output Feedback H_∞ Controllers Design for Descriptor Linear Systems Based on LMI 被引量:3
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作者 马合保 秦超英 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期57-65,共9页
This paper considers the design problem of static output feedback H ∞ controllers for descriptor linear systems with linear matrix inequality (LMI) approach. Necessary and sufficient conditions for the existence of... This paper considers the design problem of static output feedback H ∞ controllers for descriptor linear systems with linear matrix inequality (LMI) approach. Necessary and sufficient conditions for the existence of a static output feedback H ∞ controller are given in terms of LMIs. Furthermore, the design method of H ∞ controllers is provided using the solutions to the LMIs. 展开更多
关键词 descriptor linear systems static output feedback h control linear matrix inequality.
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基于IUDE算法的主动悬架H_(2)/H_(∞)控制
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作者 陈潇凯 刘宏宇 刘向 《汽车工程》 北大核心 2025年第1期137-148,共12页
汽车高性能主动悬架对提升驾乘体验感具有显著优势,鲁棒性控制算法是发挥主动悬架性能的重要保障。针对典型鲁棒控制算法难以实现有效扰动估计和补偿的问题,本文提出了H_(2)/H_(∞)-H_(2)-IUDE算法,采用IUDE算法估计并补偿扰动,并引入H_... 汽车高性能主动悬架对提升驾乘体验感具有显著优势,鲁棒性控制算法是发挥主动悬架性能的重要保障。针对典型鲁棒控制算法难以实现有效扰动估计和补偿的问题,本文提出了H_(2)/H_(∞)-H_(2)-IUDE算法,采用IUDE算法估计并补偿扰动,并引入H_(2)状态观测器,相比H_(2)/H_(∞)算法增强了鲁棒性。首先,建立了半车主动悬架控制系统模型,并定义了扰动形式。然后,提出能实现扰动估计和补偿解耦的IUDE算法,并提出一种H_(2)状态观测器,进而实现了对H_(2)/H_(∞)算法的再设计。最后,针对随机路面和减速带路面等典型工况进行仿真分析。结果表明,所提出的算法相比H_(2)/H_(∞)算法,随机路面工况的车身质心垂向加速度和俯仰角均方根值分别下降了7.6%和5.9%,对汽车平顺性有明显改善。同时,所提出的H_(2)观测器能有效估计系统状态,IUDE算法能准确估计扰动,并能够避免非解耦型UDE方法带来的悬架动挠度恶化问题,具有优异的扰动估计和灵活补偿的突出特点。 展开更多
关键词 主动悬架 不确定性与扰动观测器 h_(2)观测器 h_(2)/h_∞控制 改进的UDE算法
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H_(2)O_(2)/多相氧化脱硫催化剂研究进展
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作者 李鹏 郭凯振 +2 位作者 郑雨壑 姚红 刘川 《石化技术与应用》 2025年第1期84-90,共7页
综述了离子液体、杂多酸杂化材料、分子筛等3类催化剂应用于H_(2)O_(2)/多相氧化脱硫体系的研究进展,包括Bronsted(Lewis)酸性离子液体、以纳米管(氧化物或分子筛)为载体的负载型或金属改性的杂多酸杂化材料及Si系(非Si系)分子筛催化剂... 综述了离子液体、杂多酸杂化材料、分子筛等3类催化剂应用于H_(2)O_(2)/多相氧化脱硫体系的研究进展,包括Bronsted(Lewis)酸性离子液体、以纳米管(氧化物或分子筛)为载体的负载型或金属改性的杂多酸杂化材料及Si系(非Si系)分子筛催化剂等,并对比了各种催化剂的性能优缺点。指出今后的研究方向是开发比表面积大、稳定性高、成本低廉的载体材料,且基于载体制得的催化剂对燃料油中硫化合物的氧化活性高、耗氧量少、重复使用性良好。 展开更多
关键词 脱硫 氧化脱硫 h_(2)O_(2) 催化剂 离子液体 杂多酸 分子筛
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不同金属负载下Al_(2)O_(3)光热催化H_(2)S裂解制氢性能
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作者 于姗 汪福深 +4 位作者 黄靖元 段元刚 付梦瑶 贺桢 周莹 《天然气工业》 北大核心 2025年第2期189-198,共10页
H_(2)S直接裂解制氢是一种极具前景的H_(2)S处理技术,但现阶段的研究方法大多处于实验室研究阶段,找到一种反应条件温和、能耗低、转化率高的方法是该领域的重点研究方向之一。为此,探索了光热催化H_(2)S裂解制氢的方法,将不同金属Ni、M... H_(2)S直接裂解制氢是一种极具前景的H_(2)S处理技术,但现阶段的研究方法大多处于实验室研究阶段,找到一种反应条件温和、能耗低、转化率高的方法是该领域的重点研究方向之一。为此,探索了光热催化H_(2)S裂解制氢的方法,将不同金属Ni、Mo、Co负载到Al_(2)O_(3)上进行光热催化H_(2)S裂解制氢实验,并对比了不同金属负载下Al_(2)O_(3)的活性差异,再通过红外成像测温、X射线衍射、比表面积、紫外可见漫反射光谱、X射线光电子能谱等分析方法与技术对催化剂进行了系统表征分析。研究结果表明:①Ni、Mo、Co的负载显著提升了催化剂的催化活性,其中Mo/Al_(2)O_(3)催化剂表现出相对较好的活性,相同光照(2.85 W/cm^(2))下其H_(2)S转化率高达13.8%,H_(2)产率高达208.5±6.5μmol/(g·h);②Mo的引入提升了催化剂的光热效应,使其在相同光强下表面温度最高,同时Mo减少了表面SO_(4)^(2-)的积累,暴露出更多的活性位点,使得钼硫化物在裂解反应中表现出显著的制氢优势。结论认为:①较之于传统的热催化H_(2)S裂解制氢方法,光热催化H_(2)S裂解制氢具有更好的催化活性;②同等条件下,Mo负载下Al_(2)O_(3)的H_(2)S转化率提高了1.6倍,H_(2)产率提高了2.1倍,认识为H_(2)S裂解制氢方法提供了新的思路和技术参考。 展开更多
关键词 天然气 硫化氢 氢气 裂解制氢 氧化铝 钼硫化物 光热催化 硫酸根
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Sb^(3+)掺杂全无机Cs_(2)InCl_(5)·H_(2)O钙钛矿的制备及白光LED应用
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作者 韦星明 王荣芳 +3 位作者 韦庆敏 黄小英 陶萍芳 章浩 《化工新型材料》 北大核心 2025年第3期235-239,共5页
以氧化铟、氧化锑和氯化铯为基本原料,浓盐酸作为溶剂,采用低温水热法合成Sb^(3+)掺杂全无机Cs_(2)InCl_(5)·H_(2)O(Cs_(2)InCl_(5)·H_(2)O∶Sb^(3+))钙钛矿。研究了Sb^(3+)的掺杂量(0、2%、4%、6%、8%、10%、20%)对Cs_(2)InC... 以氧化铟、氧化锑和氯化铯为基本原料,浓盐酸作为溶剂,采用低温水热法合成Sb^(3+)掺杂全无机Cs_(2)InCl_(5)·H_(2)O(Cs_(2)InCl_(5)·H_(2)O∶Sb^(3+))钙钛矿。研究了Sb^(3+)的掺杂量(0、2%、4%、6%、8%、10%、20%)对Cs_(2)InCl_(5)·H_(2)O钙钛矿发光性能的影响。采用紫外-可见分光光谱、荧光光谱和X射线衍射仪(XRD)等表征该样品的吸收光谱、发光性能和晶体结构。结果表明,少量Sb^(3+)掺杂Cs_(2)InCl_(5)·H_(2)O钙钛矿不会改变其结构。当Sb^(3+)的掺杂量为10%时,达到最强荧光发射,发射峰波长约为620nm,荧光寿命为8.13μs。采用荧光转换法,将实验合成的Cs_(2)InCl_(5)·H_(2)O∶Sb^(3+)钙钛矿纳米晶与商用蓝色发光的BaMgAl_(10)O_(17)∶Eu和绿色发光的(Sr,Ba)_(2)SiO_(4)∶Eu荧光粉混合涂于365nm的紫外芯片上,封装得到显色指数(CRI)为91.8,CIE色坐标为(0.326,0.316),色温为5843K的白光LED。说明Cs_(2)InCl_(5)·H_(2)O∶Sb^(3+)钙钛矿纳米晶在白光LED领域具有很好的应用前景。 展开更多
关键词 Cs_(2)InCl_(5)·h_(2)O∶Sb^(3+) 钙钛矿 发光二极管 荧光
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H_(2)O_(2)制备皂角米多糖及其结构表征和抗氧化活性研究
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作者 吴雯雯 蒲龙林 +2 位作者 朱德全 邹大江 姚秋萍 《粮食与油脂》 北大核心 2025年第2期139-145,151,共8页
通过响应面法优化H_(2)O_(2)制备皂角米多糖的工艺,并对产物结构进行表征,探讨其抗氧化能力。结果表明:H_(2)O_(2)制备皂角米多糖的最佳条件为H_(2)O_(2)体积分数3.0%、提取温度80℃、提取时间7 h,在此条件下皂角米多糖得率为36.30%... 通过响应面法优化H_(2)O_(2)制备皂角米多糖的工艺,并对产物结构进行表征,探讨其抗氧化能力。结果表明:H_(2)O_(2)制备皂角米多糖的最佳条件为H_(2)O_(2)体积分数3.0%、提取温度80℃、提取时间7 h,在此条件下皂角米多糖得率为36.30%±0.76%,重均分子量为162 kDa。皂角米多糖由甘露糖、葡萄糖和半乳糖组成,其中甘露糖与半乳糖含量比值为2.14。制得的皂角米多糖主要由t-Galp、t-Manp、1,4-Manp、1,6-Glcp、1,4-Glcp、1,4,6-Galp组成,含量分别为5.49%、20.60%、43.06%、1.25%、2.79%、26.80%。当H_(2)O_(2)提取的皂角米多糖质量浓度为5.00 mg/mL时,其对DPPH·、·O-2的清除率以及还原力分别为87.40%±1.89%、83.28%±1.96%和0.723±0.027。 展开更多
关键词 皂角米 多糖 h_(2)O_(2) 结构表征 抗氧化活性
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油田采出水中80S钢和N80钢的H_(2)S/CO_(2)电化学腐蚀行为研究
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作者 宋蒲 王文珍 贾新刚 《西安石油大学学报(自然科学版)》 北大核心 2025年第1期130-136,共7页
运用腐蚀失重和电化学测试技术研究80S钢和N80钢在含H 2S/CO_(2)的油田采出水中的电化学腐蚀行为。结果表明:在模拟CO_(2)/H_(2)S的腐蚀环境中,温度是影响腐蚀速率的一大因素,80S钢和N80钢的腐蚀速率随着温度的升高而增大。两种材料表... 运用腐蚀失重和电化学测试技术研究80S钢和N80钢在含H 2S/CO_(2)的油田采出水中的电化学腐蚀行为。结果表明:在模拟CO_(2)/H_(2)S的腐蚀环境中,温度是影响腐蚀速率的一大因素,80S钢和N80钢的腐蚀速率随着温度的升高而增大。两种材料表面均发生均匀腐蚀,但N80钢表面的腐蚀程度更严重,主要是由于Cr元素可以显著提高腐蚀产物膜对金属的保护;两种材料的腐蚀电位均随着温度的升高而负移,腐蚀电流密度增大,在不同试验条件下80S钢的腐蚀电流密度均小于N80钢,表明80S钢比N80钢具有更好的抗腐蚀能力。两种材料在25℃时具有中高频区的容抗弧和低频区的感抗弧,在50℃和75℃时具有中高频区的容抗弧和低频区的Warburg阻抗,且Warburg阻抗随温度的升高表现出更明显的扩散特征。随着温度的升高,两种材料的电荷传递电阻R_(t)不断减小,Warburg阻抗的Z_(w)也减小,温度越高生成的腐蚀产物膜对金属表面的保护性能越好,80S钢比N80钢生成腐蚀产物膜的致密性更好。 展开更多
关键词 80S钢 N80钢 h_(2)S/CO_(2)腐蚀 极化曲线 极化电阻
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基于H_(2)/H_(∞)复合控制的CMG框架伺服系统参数摄动抑制方法
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作者 曹盛福 余远金 +1 位作者 赵雷 史阳阳 《空间控制技术与应用》 北大核心 2025年第1期65-74,共10页
控制力矩陀螺(control moment gyroscope,CMG)框架伺服系统常受到外部扰动力矩和内部参数摄动等多源扰动影响,导致其控制性能降低,本文重点针对参数摄动对框架伺服系统造成的影响,提出了基于H_(2)/H_(∞)复合控制的CMG框架伺服系统扰动... 控制力矩陀螺(control moment gyroscope,CMG)框架伺服系统常受到外部扰动力矩和内部参数摄动等多源扰动影响,导致其控制性能降低,本文重点针对参数摄动对框架伺服系统造成的影响,提出了基于H_(2)/H_(∞)复合控制的CMG框架伺服系统扰动抑制方法.在常规H_(∞)鲁棒控制方法中引入电机参数摄动量,在保证对外部力矩扰动具有鲁棒性的基础上,提升对内部参数摄动影响的抑制能力;结合H_(2)控制策略,提出基于状态反馈H_(2)/H_(∞)复合控制方法,在保证稳态性能的同时进一步提升系统动态响应速度.所提出的复合控制方法能够有效降低多源扰动导致的速度波动,提升系统的动态响应速度. 展开更多
关键词 CMG框架伺服系统 h_(2)/h_(∞)复合控制 参数摄动 多源扰动抑制
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On-Chip Micro Temperature Controllers Based on Freestanding Thermoelectric Nano Films for Low-Power Electronics
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作者 Qun Jin Tianxiao Guo +4 位作者 Nicolas Perez Nianjun Yang Xin Jiang Kornelius Nielsch Heiko Reith 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期98-108,共11页
Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern microelectronics.However,this inevitably exac-erbates the inhomogeneity ... Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern microelectronics.However,this inevitably exac-erbates the inhomogeneity of temperature distribution in microsystems,making precise temperature control for electronic components extremely challenging.Herein,we report an on-chip micro temperature controller including a pair of thermoelectric legs with a total area of 50×50μm^(2),which are fabricated from dense and flat freestanding Bi2Te3-based ther-moelectric nano films deposited on a newly developed nano graphene oxide membrane substrate.Its tunable equivalent thermal resistance is controlled by electrical currents to achieve energy-efficient temperature control for low-power electronics.A large cooling temperature difference of 44.5 K at 380 K is achieved with a power consumption of only 445μW,resulting in an ultrahigh temperature control capability over 100 K mW^(-1).Moreover,an ultra-fast cooling rate exceeding 2000 K s^(-1) and excellent reliability of up to 1 million cycles are observed.Our proposed on-chip temperature controller is expected to enable further miniaturization and multifunctional integration on a single chip for microelectronics. 展开更多
关键词 Temperature control Low-power electronics On-chip micro temperature controller Freestanding thermoelectric nano films Temperature-sensitive components
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含H_(2)S/CO_(2)集输管线用复配缓蚀剂的合成及性能研究
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作者 李小龙 张娟涛 +3 位作者 魏晓静 高宁 王远 贺波 《石油管材与仪器》 2025年第1期27-33,共7页
针对塔里木盆地某区块含H_(2)S/CO_(2)介质集输管线腐蚀严重的问题,以月桂酸、N-(2-羟乙基)乙二胺为原料通过酰胺反应和环化反应合成了咪唑啉中间体,再加入氯化苄,合成咪唑啉季铵盐缓蚀剂;以喹啉、氯化苄为原料,合成了喹啉季铵盐缓蚀剂... 针对塔里木盆地某区块含H_(2)S/CO_(2)介质集输管线腐蚀严重的问题,以月桂酸、N-(2-羟乙基)乙二胺为原料通过酰胺反应和环化反应合成了咪唑啉中间体,再加入氯化苄,合成咪唑啉季铵盐缓蚀剂;以喹啉、氯化苄为原料,合成了喹啉季铵盐缓蚀剂;通过两种缓蚀剂复配并利用单因素失重法试验优选得到一种KM-1缓蚀剂(咪唑啉季铵盐与喹啉季铵盐的质量比为1∶3)。通过动态高温高压釜试验考察其在60℃、含H_(2)S/CO_(2)模拟水中对L245NS钢的缓蚀性能。结果表明,KM-1缓蚀剂的添加量为150 mg/L时缓蚀性能最佳,此时L245NS试片的平均腐蚀速率为0.0214 mm/a,缓蚀率可达到93.7%,主要归因于KM-1缓蚀剂可在试片表面吸附形成保护膜从而有效抑制了腐蚀。 展开更多
关键词 集输管线 咪唑啉季铵盐 喹啉季铵盐 h_(2)S腐蚀 CO_(2)腐蚀
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Electronic structure and ultraviolet spectra of p-C_(6)H_(4)-C_(20)
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作者 CHEN Xin 《原子与分子物理学报》 CAS 北大核心 2025年第3期21-28,共8页
Geometry optimization of p-C_(6)H_(4)-connected cyclo[20]carbon(p-C_(6)H_(4)-C_(20))was carried out at M062X/6-311G(d,p)level,three kinds of bond orders(Mayer,Laplacian,and Wiberg),electron-hole distributions,localize... Geometry optimization of p-C_(6)H_(4)-connected cyclo[20]carbon(p-C_(6)H_(4)-C_(20))was carried out at M062X/6-311G(d,p)level,three kinds of bond orders(Mayer,Laplacian,and Wiberg),electron-hole distributions,localized orbital locators(LOL),and infrared(IR)spectrum were also performed at the same level.Based on TD-DFT M062X/6-311G(d,p)method,the first 20 excited states and ultraviolet(UV)spectra of p-C_(6)H_(4)-C_(20) were calculated.Calculation results of π-electron delocalization analyses prove thatπ-electron delocalization of p-C_(6)H_(4)-C_(20) is more likely to occur on shorter C-C bonds rather than longer C-C bonds,and inside/outside of the ring plane rather than above/below the ring plane.Two absorption peaks of p-C_(6)H_(4)-C_(20) locate at about 319 nm and 236 nm,respectively. 展开更多
关键词 p-C_(6)h_(4)-C_(20) Bone orders UV spectrum Electron-hole analyses π-electron delocalization analyses
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基于H_(∞)观测器和迭代学习的泊车路径跟踪横向控制
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作者 王杰 刘丛志 张澧桐 《汽车工程学报》 2025年第1期69-80,共12页
泊车跟踪精度直接影响泊车效率、剩余泊车空间甚至泊车安全。当前,自动泊车路径跟踪绝大部分采用基于模型的反馈控制,模型参数的不确定性会导致泊车路径跟踪算法控制性能下降,进而产生较大的跟踪误差。为减小模型参数不确定性对泊车路... 泊车跟踪精度直接影响泊车效率、剩余泊车空间甚至泊车安全。当前,自动泊车路径跟踪绝大部分采用基于模型的反馈控制,模型参数的不确定性会导致泊车路径跟踪算法控制性能下降,进而产生较大的跟踪误差。为减小模型参数不确定性对泊车路径跟踪效果的影响,提出了基于迭代学习的前馈控制策略。考虑到在时间域对系统进行迭代学习控制通常受执行器实际速度的影响,所以控制时将系统由时间域转换到与期望路径相关的空间域。由于系统模型中的一些状态变量难以测量,且系统无法满足D型迭代学习率收敛条件,所以提出H_(∞)观测器设计准则以准确估计状态信息。同时,构造具有观测误差的增广系统以进行迭代学习控制,在线性二次型最优控制(LQR)的初次泊车跟踪信息基础上进一步减小泊车路径跟踪误差。进行硬件在环(HIL)测试,验证了该方法具有良好的实际应用潜力。试验结果表明,经过多次迭代后,与LQR初次控制的泊车跟踪效果相比,所提出的控制方法能更准确地跟踪期望路径。 展开更多
关键词 路径跟踪 迭代学习 h_(∞)观测器 自动泊车
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Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls
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作者 Yang Shi Mingjun Wu +14 位作者 Shengbo Ge Jianzhang Li Anoud Saud Alshammari Jing Luo Mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed M.Asiri Runzhou Huang Hua Hou Zeinhom M.El‑Bahy Zhanhu Guo Chong Jia Kaimeng Xu Xiangmeng Chen 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期98-134,共37页
Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and... Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field. 展开更多
关键词 Biomass materials Electromagnetic interference shielding Micro-nano structure interface control CONDUCTIVITY
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Scalable Ir‑Doped NiFe_(2)O_(4)/TiO_(2) Heterojunction Anode for Decentralized Saline Wastewater Treatment and H_(2) Production
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作者 Sukhwa Hong Jiseon Kim +3 位作者 Jaebeom Park Sunmi Im Michael R.Hoffmann Kangwoo Cho 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期1-18,共18页
Wastewater electrolysis cells(WECs)for decentralized wastewater treatment/reuse coupled with H_(2) production can reduce the carbon footprint associated with transportation of water,waste,and energy carrier.This study... Wastewater electrolysis cells(WECs)for decentralized wastewater treatment/reuse coupled with H_(2) production can reduce the carbon footprint associated with transportation of water,waste,and energy carrier.This study reports Ir-doped NiFe_(2)O_(4)(NFI,~5 at%Ir)spinel layer with TiO_(2) overlayer(NFI/TiO_(2)),as a scalable heterojunction anode for direct electrolysis of wastewater with circumneutral pH in a single-compartment cell.In dilute(0.1 M)NaCl solutions,the NFI/TiO_(2) marks superior activity and selectivity for chlorine evolution reaction,outperforming the benchmark IrO_(2).Robust operation in near-neutral pH was confirmed.Electroanalyses including operando X-ray absorption spectroscopy unveiled crucial roles of TiO_(2) which serves both as the primary site for Cl−chemisorption and a protective layer for NFI as an ohmic contact.Galvanostatic electrolysis of NH4+-laden synthetic wastewater demonstrated that NFI/TiO_(2)not only achieves quasi-stoichiometric NH_(4)^(+)-to-N_(2)conversion,but also enhances H_(2)generation efficiency with minimal competing reactions such as reduction of dissolved oxygen and reactive chlorine.The scaled-up WEC with NFI/TiO_(2)was demonstrated for electrolysis of toilet wastewater. 展开更多
关键词 Wastewater electrolysis cell Ir-doped NiFe_(2)O_(4) Reactive chlorine species Decentralized h_(2)production On-site wastewater treatment
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Comprehensive strategies for the prevention and control of pine wilt disease in China:a review and future directions
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作者 Fengmao Chen Min Li 《Journal of Forestry Research》 2025年第1期505-509,共5页
Pinewood nematode is a devastating forest pathogen and is considered a quarantine organism worldwide.First identified in China 40 years ago,the disease has been spreading since.In response,Chinese authorities have int... Pinewood nematode is a devastating forest pathogen and is considered a quarantine organism worldwide.First identified in China 40 years ago,the disease has been spreading since.In response,Chinese authorities have introduced new requirements for preventing and controlling the disease.This paper proposes a new and highly effective preventive drug,a trunk injection agent usable at normal temperatures.Its use is suggested for localized epidemic areas to reduce diseased and dead trees and as a preventive measure in adjacent non-epidemic areas to prevent the infection from spreading,particularly protecting important and ancient pine trees. 展开更多
关键词 China Pinewood nematode control measures control mode Epidemic eradication
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Hash-based FDI attack-resilient distributed self-triggered secondary frequency control for islanded microgrids
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作者 Xing Huang Yulin Chen +4 位作者 Donglian Qi Yunfeng Yan Shaohua Yang Ying Weng Xianbo Wang 《Global Energy Interconnection》 2025年第1期1-12,共12页
Given the rapid development of advanced information systems,microgrids(MGs)suffer from more potential attacks that affect their operational performance.Conventional distributed secondary control with a small,fixed sam... Given the rapid development of advanced information systems,microgrids(MGs)suffer from more potential attacks that affect their operational performance.Conventional distributed secondary control with a small,fixed sampling time period inevitably causes the wasteful use of communication resources.This paper proposes a self-triggered secondary control scheme under perturbations from false data injection(FDI)attacks.We designed a linear clock for each DG to trigger its controller at aperiodic and intermittent instants.Sub-sequently,a hash-based defense mechanism(HDM)is designed for detecting and eliminating malicious data infiltrated in the MGs.With the aid of HDM,a self-triggered control scheme achieves the secondary control objectives even in the presence of FDI attacks.Rigorous theoretical analyses and simulation results indicate that the introduced secondary control scheme significantly reduces communication costs and enhances the resilience of MGs under FDI attacks. 展开更多
关键词 MICROGRIDS Distributed secondary control Self-triggered control hash algorithms False data injection attack
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Constructing ether-rich and carboxylate hydrogen bonding sites in protic ionic liquids for efficient and simultaneous membrane separation of H_(2)S and CO_(2) from CH_(4)
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作者 Ping Zhang Xingyun Ma +3 位作者 Zhuoheng Tu Xiaomin Zhang Xingbang Hu Youting Wu 《Green Energy & Environment》 2025年第3期560-572,共13页
Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-... Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-based membranes.Herein,we firstly reported the incorporation of protic ILs (PILs) having ether-rich and carboxylate sites (ECPILs) into poly(ether-block-amide)(Pebax) matrix for efficient separation H_(2)S and CO_(2)from CH_(4).Notably,the optimal permeability of H_(2)S reaches up to 4310 Barrer (40C,0.50 bar) in Pebax/ECPIL membranes,along with H_(2)S/CH_(4)and (H_(2)StCO_(2))/CH_(4)selectivity of 97.7 and 112.3,respectively.These values are increased by 1125%,160.8%and 145.9%compared to those in neat Pebax membrane.Additionally,the solubility and diffusion coefficients of the gases were measured,demonstrating that ECPIL can simultaneously strengthen the dissolution and diffusion of H_(2)S and CO_(2),thus elevating the permeability and permselectivity.By using quantum chemical calculations and FT-IR spectroscopy,the highly reversible multi-site hydrogen bonding interaction between ECPILs and H_(2)S was revealed,which is responsible for the fast permeation of H_(2)S and good selectivity.Furthermore,H_(2)S/CO_(2)/CH_(4)(3/3/94 mol/mol) ternary mixed gas can be efficiently and stably separated by Pebax/ECPIL membrane for at least 100 h.Overall,this work not only illustrates that PILs with ether-rich and carboxylate hydrogen bonding sites are outstanding materials for simultaneous removal of H_(2)S and CO_(2),but may also provide a novel insight into the design of membrane materials for natural gas upgrading. 展开更多
关键词 h_(2)S Protic ionic liquid Multi-site hydrogen bonding interaction Membrane separation Natural gas purification
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Finite time hybrid synchronization of heterogeneous duplex complex networks via time-varying intermittent control
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作者 Cheng-Jun Xie Xiang-Qing Lu 《Chinese Physics B》 2025年第4期354-363,共10页
This paper study the finite time internal synchronization and the external synchronization(hybrid synchronization)for duplex heterogeneous complex networks by time-varying intermittent control.There few study hybrid s... This paper study the finite time internal synchronization and the external synchronization(hybrid synchronization)for duplex heterogeneous complex networks by time-varying intermittent control.There few study hybrid synchronization of heterogeneous duplex complex networks.Therefore,we study the finite time hybrid synchronization of heterogeneous duplex networks,which employs the time-varying intermittent control to drive the duplex heterogeneous complex networks to achieve hybrid synchronization in finite time.To be specific,the switch frequency of the controllers can be changed with time by devise Lyapunov function and boundary function,the internal synchronization and external synchronization are achieved simultaneously in finite time.Finally,numerical examples are presented to illustrate the validness of theoretical results. 展开更多
关键词 finite time synchronization time-varying intermittent control duplex heterogeneous networks complex networks
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Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H_(2)O_(2) synthesis coupled with biomass valorization
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作者 Jiaye Li Shuang Pan +1 位作者 Yihuang Chen Qiong Liu 《Journal of Energy Chemistry》 2025年第1期215-225,共11页
Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production method.However,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating ... Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production method.However,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative by-products.Herein,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H_(2)O_(2)and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride(CNRb).The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h^(-1)for H_(2)O_(2)generation and photooxidation rate of 3.75 mM h^(-1)for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion(SCC)efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical formation.This is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product formation.This study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H_(2)O_(2)coupled with biomass valorization. 展开更多
关键词 Atomic economy Radical pathway regulation Photocatalytic h_(2)O_(2)synthesis Rubidium atom coordination Biomass valorization
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Exponential Attitude-Orbit Coordinated Control for Gravitational-Wave Detection Spacecraft Formation with Large-Scale Communication Delays
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作者 XING Youpeng SONG Yinsheng +1 位作者 YIN Zeyang CHEN Xiaofang 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第1期70-79,共10页
This paper concerns the exponential attitude-orbit coordinated control problems for gravitational-wave detection formation spacecraft systems.Notably,the large-scale communication delays resulting from oversized inter... This paper concerns the exponential attitude-orbit coordinated control problems for gravitational-wave detection formation spacecraft systems.Notably,the large-scale communication delays resulting from oversized inter-satellite distance of space-based laser interferometers are first modeled.Subject to the delayed communication behaviors,a new delay-dependent attitude-orbit coordinated controller is designed.Moreover,by reconstructing the less conservative Lyapunov-Krasovskii functional and free-weight matrices,sufficient criteria are derived to ensure the exponential stability of the closed-loop relative translation and attitude error system.Finally,a simulation example is employed to illustrate the numerical validity of the proposed controller for in-orbit detection missions. 展开更多
关键词 gravitational-wave detection spacecraft formation attitude-orbit coordinated control large-scale communication delays exponential stability
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