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Analysis and Design of Time-Delay Impulsive Systems Subject to Actuator Saturation

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 196-204页

作者： Chenhong Zhu xiuping Han Xiaodi Li IEEE the School of Mathematics and Statistics Shandong Normal UniversityJi'nan 250014China the Center for Control and Engineering Computation Shandong Normal UniversityJi'nan 250014China

This paper investigates the exponential stability and performance analysis of nonlinear time-delay impulsive systems subject to actuator saturation. When continuous dynamics is unstable, under some conditions, it is shown that the system can be stabilized by a class of saturated delayed-impulses regardless of the length of input delays. Conversely, when the system is originally stable, it is shown that under some conditions, the system is robust with respect to sufficient small delayed-impulses. Moreover, the design problem of the controller with the goal of obtaining a maximized estimate of the domain of attraction is formulated via a convex optimization problem. Three examples are provided to demonstrate the validity of the main results.

关键词： Delayed impulses impulsive control impulsive disturbance nonlinear systems saturation

Evaluation of CLDAS and GPM Precipitation Products over the Tibetan Plateau in Summer 2005–2021 Based on Hourly Rain Gauge Observations

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Journal of Meteorological Research 2024年第4期38卷 749-767页

作者： Qiaohua LIU xiuping YAO School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing 210044 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 China Meteorological Administration Training Centre Beijing 100081

Accurate,reliable,and high spatiotemporal resolution precipitation products are essential for precipitation research,hydrological simulation,disaster warning,and many other applications over the Tibetan Plateau(TP).The Global Precipitation Measurement(GPM) data are widely recognized as the most reliable satellite precipitation product for the *** China Meteorological Administration(CMA) Land Data Assimilation System(CLDAS) precipitation fusion dataset(CLDAS-Prcp),hereafter referred to as CLDAS,is a high-resolution,self-developed precipitation product in China with regional *** on the TP,this study provides a long-term evaluation of CLDAS and GPM from various aspects,including characteristics on different timescales,diurnal variation,and elevation impacts,based on hourly rain gauge data in summer from 2005 to *** results show that CLDAS and GPM are highly effective alternatives to the rain gauge records over the *** both perform well for precipitation amount and frequency on multiple *** tends to overestimate precipitation amount and underestimate precipitation frequency over the ***,GPM tends to overestimate both precipitation amount and *** difference between them mainly lies in the trace *** and GPM effectively capture rainfall events,but their performance decreases significantly as intensity *** both show better accuracy in diurnal variation of precipitation amount than frequency,and their performance tends to be superior during nighttime compared to the ***,there are some differences of the two against rain gauge observations in diurnal variation,especially in the phase of the diurnal *** performance of CLDAS and GPM varies at different *** both have the best performance over 3000–3500 *** elevation dependence of CLDAS is relatively minor,while GPM shows a stronger elevation dependence in terms of precipitation *** tends to ov

关键词： China Meteorological Administration(CMA)Land Data Assimilation System(CLDAS)precipitation fusion dataset(CLDAS-Prcp) Global Precipitation Measurement(GPM) Tibetan Plateau(TP) precipitation evaluation

Development of DArT markers for a linkage map of flue-cured tobacco

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Chinese Science Bulletin 2013年第6期58卷 641-648页

作者： lu xiuping GUI YiJie XIAO BingGuang LI YongPing TONG ZhiJun LIU Yun BAI XueFei WU WeiRen XIA Ling HUTTNER Eric KILIAN Adrzej FAN LongJiang Department of Agronomy Zhejiang University Yunnan Academy of Tobacco Agricultural Sciences and China Tobacco Breeding Research Center at Yunnan DArT P/L PO Box 7141YarralumlaCanberraACT 2600Australia

Tobacco(Nicotiana tabacum) is one of the most economically important nonfood crops,and flue-cured tobacco accounts for approximately 80% of world tobacco *** extremely narrow genetic diversity in the tobacco pool has led to a low efficiency of PCR-based molecular markers(such as AFLP and SSR).Diversity Arrays Technology(DArT) is a high-throughput hybridisation-based marker system that has been developed in many plants including wheat,which,like tobacco,has a complex *** this study,we developed a tobacco DArT chip that included 7680 representative sequence tags based on typical tobacco *** 1076 DArT markers of flue-cured tobacco were identified and most(82.1%) of their polymorphism information contents(PICs) were greater than *** integrated linkage map that included 851 markers(238 DArT and 613 SSR),which is the highest density map of flue-cured tobacco to date,was *** chip-based DArT system provides an alternative in high-throughput marker genotyping for tobacco.

关键词： DART 分子标记连锁图谱烤烟烟草生产遗传多样性多态信息含量标记系统

Junshanyinzhen tea extract prevents obesity by regulating gut microbiota and metabolic endotoxemia in high-fat diet fed rats

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Food Science and Human Wellness 2024年第4期13卷 2036-2047页

作者： Jian Ouyang xiuping Li Changwei Liu Danmin lu Jie Ouyang Fang Zhou Qi Liu Jianan Huang Zhonghua Liu Key Laboratory of Tea Science of Ministry of Education Hunan Agricultural UniversityChangsha 410128China National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals Hunan Agricultural UniversityChangsha 410128China Co-Innovation Center of Education Ministry for Utilization of Botanical Functional Ingredients Hunan Agricultural UniversityChangsha 410128China Key Laboratory for Evaluation and Utilization of Gene Resources of Horticultural Crops Ministry of Agriculture and Rural AffairsHunan Agricultural UniversityChangsha 410128China

Obesity is associated with gut dysbiosis and metabolic *** tea extract(JSTE)reduced fat accumulation and body weight in obese ***,the effects and mechanism of JSTE in preventing obesity were ***,we used different doses of JSTE(75,150 and 300 mg/(kg·day))to evaluate the effect on high-fat diet(HFD)-induced rats under 8 weeks of ***,our results showed that JSTE could significantly reduce body weight gain,blood lipid levels and fat accumulation,improve fatty damage in liver tissue(P<0.05).In addition,JSTE increased the expression of intestinal tight junction proteins(P<0.05),relieved metabolic endotoxemia(P<0.05)and chronic low-grade inflammation in HFD *** of fecal samples showed that JSTE could effectively reverse the microbial diversity and the ratio of Firmicutes to Bacteroidetes to normal levels in HFD-fed *** and Erysipelotrichaceae,which are positively related to obesity,were decreased by JSTE intervention(P<0.05).while Bifidobacteriaceae,Bacteroidaceae,Akkermansia,and Clostridium,which are negatively related to obesity,were ***,these results suggested that JSTE might effectively prevent obesity by modulating gut microbiota dysbiosis,intestinal barrier dysfunction,metabolic endotoxemia and chronic low-grade infl ammation in HFD-induced rats.

关键词： Junshanyinzhen tea Obesity Gut microbiota Gut barrier function Metabolic endotoxemia

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ABS／改性抗菌纳米ZnO的力学及抑菌性能

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合成树脂及塑料 2006年第5期23卷 11-13,77页

作者：卢秀萍邵金璐天津科技大学材料科学与化工学院天津300222

采用偶联剂处理法对抗菌纳米ZnO表面进行改性,制备了丙烯腈-丁二烯-苯乙烯共聚物(ABS)／改性抗菌纳米ZnO复合材料。结果表明:改性抗菌纳米ZnO质量分数为3％时,复合材料的改性效果最佳,其拉伸强度、断裂伸长率、硬度、缺口冲击强度和无... 详细信息

采用偶联剂处理法对抗菌纳米ZnO表面进行改性,制备了丙烯腈-丁二烯-苯乙烯共聚物(ABS)／改性抗菌纳米ZnO复合材料。结果表明:改性抗菌纳米ZnO质量分数为3％时,复合材料的改性效果最佳,其拉伸强度、断裂伸长率、硬度、缺口冲击强度和无缺口冲击强度分别较纯ABS树脂提高37．4％,3．4％,44．0％,15．8％,11．8％;复合材料对大肠杆菌、金色葡萄球菌的抑菌率分别达到76．3％及84．0％。

关键词：丙烯腈-丁二烯-苯乙烯共聚物改性抗菌纳米氧化锌复合材料力学性能抑菌性能

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PP/纳米ZnO的紫外光老化性能

合成树脂及塑料 2007年第4期24卷 71-74页

作者：卢秀萍邵金璐天津科技大学材料科学与化工学院天津300457

将纳米ZnO(nano-ZnO)用钛酸酯偶联剂表面处理后制备聚丙烯(PP)/nano-ZnO复合材料。研究了nano-ZnO含量对复合材料耐老化性能的影响。nano-ZnO可明显改善PP树脂的紫外光老化性能。当w(nano-ZnO)为3%时,复合材料老化前后的性能差和纯PP树... 详细信息

将纳米ZnO(nano-ZnO)用钛酸酯偶联剂表面处理后制备聚丙烯(PP)/nano-ZnO复合材料。研究了nano-ZnO含量对复合材料耐老化性能的影响。nano-ZnO可明显改善PP树脂的紫外光老化性能。当w(nano-ZnO)为3%时,复合材料老化前后的性能差和纯PP树脂老化前后的性能差分别为:拉伸强度1.9 MPa和3.1 MPa、断裂伸长率为29.0%和66.7%、缺口冲击强度为1.1 kJ/m^2和2.9 kJ/m^2、无缺口冲击强度为1.5 kJ/m^2和3.2 kJ/m^2、球压痕硬度为4.8 MPa和5.8 MPa、维卡软化温度为3.3℃和7.0℃。

关键词：聚丙烯纳米氧化锌复合材料紫外光老化

乳液共混法制备微纤化纤维素/聚乳酸生物复合材料及性能

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高分子材料科学与工程 2017年第2期33卷 142-146,151页

作者：吴宇博卢秀萍廖娟天津科技大学化工与材料学院天津300457

为了提高聚乳酸(PLA)的韧性和刚性,扩大应用范围,分别以PLA为基体,微纤化纤维素(MFC)为增强材料,通过乳液共混法制备出MFC/PLA生物复合材料。采用扫描电镜、偏光显微镜和万能电子试验机等研究了复合材料的断面形貌、球晶形态和力学性能... 详细信息

为了提高聚乳酸(PLA)的韧性和刚性,扩大应用范围,分别以PLA为基体,微纤化纤维素(MFC)为增强材料,通过乳液共混法制备出MFC/PLA生物复合材料。采用扫描电镜、偏光显微镜和万能电子试验机等研究了复合材料的断面形貌、球晶形态和力学性能等。结果表明,通过乳液共混法可将MFC均匀分散在PLA基体中制备MFC/PLA生物复合材料;适量MFC可显著细化PLA的球晶尺寸,提高PLA的力学性能。当MFC质量分数为0.6%时,复合材料的拉伸强度、弹性模量、弯曲强度和缺口冲击强度分别较纯PLA提高了15.6%、21.1%、30.6%和53.6%。

关键词：微纤化纤维素聚乳酸复合材料形貌球晶力学性能

Diagnosis of the Kinetic Energy of the“21·7”Extreme Torrential Rainfall Event in Henan Province,China

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Advances in Atmospheric Sciences 2024年第1期41卷 73-83页

作者： xiuping YAO Ruoying LI Xiaohong BAO Qiaohua LIU China Meteorological Administration Training Centre Beijing 100081China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China College of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China

An extreme torrential rain(ETR)event occurred in Henan Province,China,during 18-21 July *** on hourly rain-gauge observations and ERA5 reanalysis data,the ETR was studied from the perspective of kinetic energy(K),which can be divided into rotational wind(V_(R))kinetic energy(K_(R)),divergent wind kinetic energy(K_(D)),and the kinetic energy of the interaction between the divergent and rotational winds(K_(RD)).According to the hourly precipitation intensity variability,the ETR process was divided into an initial stage,a rapid increase stage,and maintenance *** showed that the intensification and maintenance of ETR were closely related to the upper-level K,and most closely related to the upperlevel K_(R),with a correlation coefficient of up to *** particular,the peak value of hourly rainfall intensity lagged behind the K_(R) by 8 ***,diagnosis showed that K transformation from unresolvable to resolvable scales made the ETR increase *** meridional rotational wind(u_(R))and meridional gradient of the geopotential(φ)jointly determined the conversion of available potential energy(APE)to K_(R) through the barotropic process,which dominated the rapid enhancement of K_(R) and then caused the rapid increase in *** transportation of K by rotational wind consumed K_(R),and basically offset the K_(R) produced by the barotropic process,which basically kept K_(R) stable at a high value,thus maintaining the ETR.

关键词： extreme torrential rain rotational kinetic energy kinetic energy generation and transport barotropic process

Oxidative Desulfurization of Fuel Oil with H_(3)PO_(4)-based Deep Eutectic Solvents

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 178-186页

作者： Li xiuping Zhang Jiayin Hou Liangpei Zhao Rongxiang School of Petrochemical Engineering Liaoning Petrochemical UniversityFushun 113001China

A series of Lewis-acid deep eutectic solvents (DESs) were synthesized by stirring phosphoric acid and zincchloride as raw materials at 80℃ to form H_(3)PO_(4)/nZnCl_(2) (n = 0.1, 0.25, 0.5, 0.75, 1). The DESs were characterized byFourier transform infrared spectrophotometry (FT-IR), thermogravimetry/differential thermogravimetry (TG/DTG), andelectron spray ionization mass spectrometry (ESI-MS). The DESs were used as both extractants and catalysts to removedibenzothiophene from fuels via oxidative desulfurization (ODS). Experiments were performed to investigated the influenceof factors such as composition of DES, temperature, oxidant dosage (molar ratio of O:S), DES dosage (volume ratio ofDES:oil), and number of cycles on desulfurization rate. The results indicated that the removal rate of dibenzothiophene (DBT)was affected by the Lewis acidic DESs, with that of H_(3)PO_(4)/0.25∙ZnCl_(2) reaching 96.4% under optimal conditions (Voil=5 mL,VDES=1 mL, an oxidant dosage of 6, T=50 ℃). After six cycles, the desulfurization rate of H_(3)PO_(4)/0.25∙ZnCl_(2) remained above94.1%. The apparent activation energy of dibenzothiophene (DBT) removal reaction was determined by a pseudo-first orderkinetic equation according to the Arrhenius equation to be 32.34 kJ/mol, as estimated. A reaction mechanism is proposedbased on the experimental data and characterization results.

关键词： deep eutectic solvents phosphoric acid zinc chloride oxidative desulfurization