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Oxidation of 3,4-dihydropyrimidin-2(1H)-ones with nitrosonium(NO^+)

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Chinese Chemical Letters 2009年第10期20卷 1183-1186页

作者： Rui Rui liang Guai li wu Wen tao wu Long Min wu State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China

3,4-Dihydropyrimidin-2（1H）-ones （DHPMs） were oxidized with 1.2 equiv, of nitrosonium tetrafluoroborate （NO^＋BF4^-） to pyrimidin-2（1H）-ones in acetonitrile at room temperature in high yields.

关键词： Dihydropyrimidinone Nitrosonium Oxidation

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基于粒子流滤波的视觉定位算法

信息技术 2024年第8期48卷 134-138页

作者：杨琼楠吴力涛仇晨光中国兵器工业第214研究所苏州研发中心江苏苏州215136

针对基于粒子滤波的视觉定位算法存在的粒子需求量大以及重采样中粒子贫化而导致的计算量大、定位精度差等问题,提出了一种采用粒子流滤波进行优化的视觉定位算法。该算法通过一个微分方程进行粒子的移动,利用粒子流完成随机样本集从先... 详细信息

针对基于粒子滤波的视觉定位算法存在的粒子需求量大以及重采样中粒子贫化而导致的计算量大、定位精度差等问题,提出了一种采用粒子流滤波进行优化的视觉定位算法。该算法通过一个微分方程进行粒子的移动,利用粒子流完成随机样本集从先验分布到后验分布的更新,进而避免了“粒子退化”现象,最后利用参量近似法来求解粒子流滤波,实验结果证明,该算法减少了算法计算量和运行时间,提高了系统的精度。

关键词：粒子流滤波粒子滤波视觉里程计贝叶斯滤波非线性滤波

Radiofrequency ablation vs hepatic resection for solitary colorectal liver metastasis:A meta-analysis

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World Journal of Gastroenterology 2011年第36期17卷 4143-4148页

作者： Yun-Zi wu Bin li tao Wang Shuang-Jia Wang Yan-Ming Zhou Department of Hepato-Biliary-Pancreato-Vascular Surgery the First Affiliated Hospital of Xiamen UniversityXiamen 361003Fujian ProvinceChina

AIM:To evaluate the comparative therapeutic efficacy of radiofrequency ablation (RFA) and hepatic resection (HR) for solitary colorectal liver metastases (CLM).METHODS:A literature search was performed to identify comparative studies reporting outcomes for both RFA and HR for solitary *** odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using either the fixed effects model or random effects ***:Seven nonrandomized controlled trials studies were included in this *** studies included a total of 847 patients:273 treated with RFA and 574 treated with *** 5 years overall survival rates in the HR group were significantly better than those in the RFA group (OR:0.41,95% CI:0.22-0.90,P=0.008).RFA had a higher rate of local intrahe-patic recurrence compared to HR (OR:4.89,95% CI:1.73-13.87,P=0.003).No differences were found between the two groups with respect to postoperative morbidity and ***:HR was superior to RFA in the treatment of patients with solitary ***,the findings have to be carefully interpreted due to the lower level of evidence.

关键词： Hepatic resection Colorectal liver metastases Radiofrequency ablation Efficacy Meta-analysis

Effects of ignition voltage and electrode structure on electric ignition and combustion characteristics of Ammonium Dinitramide(ADN)-based liquid propellants in electric ignition mode in inert gas environment

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Chinese Journal of Aeronautics 2024年第4期37卷 229-242页

作者： Lei li Guoxiu li Hongmeng li Zhaopu YAO tao ZHANG Jinze wu Shuo ZHANG School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Beijing Institute of Control Engineering Beijing 100190China

Hydrazine is toxic and carcinogenic, which greatly increases the difficulty of application and no longer meets the needs of green aerospace. As a green propellant, the Ammonium Dinitramide(ADN)-based liquid propellant has the advantages of higher specific impulse, being non-toxic,pollution-free, and easy storage. However, an ADN-based space engine in orbit has exposed the problems of high-temperature deactivation of catalysts and cold-start failure. An active ignition technology—electric ignition technology was explored in this paper to break through the technical bottleneck of catalyst deactivation and the inability to a cold start. An experimental system of a constant-volume combustor for the ADN-based liquid propellant based on the electric ignition method was established. The electric ignition and combustion characteristics of the ADN-based liquid propellant in a volume combustor with an electric ignition method were studied. The influencing mechanisms of the ignition voltage and the electrode structure on the electric ignition characteristics of the ADN-based liquid propellant were investigated. An elevation of the ignition voltage could facilitate the ignition process of the ADN-based liquid propellant, curtail electric energy input and heating effect, while exerting an adverse impact on the combustion process of the *** increase in the ignition voltage enhanced the ignition process of the propellant while simultaneously suppressing its combustion process when utilizing mesh electrodes. Compared to the strip electrodes, the mesh electrodes increased the contact area between the electrodes and the propellant,increased the electric energy input power in the electric ignition process, and reduced the ignition delay time. The mesh electrodes could promote the combustion process of the propellant to a certain extent.

关键词： ADN-based liquid propellant Resistive ignition Electrical ignition characteristic Combustion Inert gas

The protective effect of cyclodextrin on the color quality and stability of Cabernet Sauvignon red wine

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Journal of Integrative Agriculture 2024年第1期23卷 310-323页

作者： Caiyun liu Lulu wu Shuyue Fan Yongsheng tao Yunkui li College of Enology Northwest A&F UniversityYangling 712100China Ningxia Helan Mountain’s East Foothill Wine Experiment and Demonstration Station of Northwest A&F University Minning 750104China

The impact of cyclodextrins(CDs)on wine quality and stability remains largely *** study systematically assessed the protective effect of the post-fermentation addition of CDs on color stability of red wine from the viewpoints of color characteristics,copigmentation and phenolic *** grey relational analysis(GRA)and principal component analysis(PCA)methods were employed to dissect the key effective determinants related to color *** addition of CDs induced a significant hyperchromic effect of 8.19-25.40%,a significant bathochromic effect and an enhancement of the color ***,the evolution of anthocyanin forms and the content of monomeric anthocyanins revealed that β-CD is a superior favorable cofactor during wine aging,but for long-term aging,2-HP-β-CD and 2-HP-γ-CD are more beneficial in promoting the formation of polymerized anthocyanins and color *** work provides an important reference for the use of CDs to enhance the color quality and stability of red wines.

关键词： cyclodextrins color properties copigmentation Helan Mountain’s East Foothill red wine aging

Asynchronous Learning-Based Output Feedback Sliding Mode Control for Semi-Markov Jump Systems: A Descriptor Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1358-1369页

作者： Zheng wu Yiyun Zhao Fanbiao li tao Yang Yang Shi Weihua Gui School of Automation Central South UniversityChangsha 410083China Power Electronics Machines and Control GroupThe University of NottinghamNottingham NG72RDUK Department of Mechanical Engineering University of VictoriaVictoria BC V8W 3P6Canada IEEE

This paper presents an asynchronous output-feed-back control strategy of semi-Markovian systems via sliding mode-based learning *** with most literature results that require exact prior knowledge of system state and mode information,an asynchronous output-feedback sliding sur-face is adopted in the case of incompletely available state and non-synchronization *** holonomic dynamics of the sliding mode are characterized by a descriptor system in which the switching surface is regarded as the fast subsystem and the system dynamics are viewed as the slow *** upon the co-occurrence of two subsystems,the sufficient stochastic admissibility criterion of the holonomic dynamics is derived by utilizing the characteristics of cumulative distribution ***,a recursive learning controller is formulated to guarantee the reachability of the sliding manifold and realize the chattering reduction of the asynchronous switching and sliding ***,the proposed theoretical method is substantia-ted through two numerical simulations with the practical contin-uous stirred tank reactor and F-404 aircraft engine model,respectively.

关键词： Asynchronous switching learning-based control output feedback semi-Markovian jump systems sliding mode con-trol(SMC).

Accelerated aging and frailty in cardiovascular diseases

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Journal of Geriatric Cardiology 2024年第8期21卷 828-830页

作者： Xue-Hua CHENG tao wu li HAN Department of Traditional Chinese Medicine Geriatrics Huadong Hospital Affiliated to Fudan UniversityShanghaiChina

Aging is the greatest risk factor for cardiovascular disease(CVD),which is the most common cause of death in European countries.[1]It is estimated that during the period from 2020 to 2022,there were 9.0%more excess deaths from CVD than expected.[2]By 2030,approximately 20%of the population will be aged 65 years and older,and CVD will account for 40%of deaths in this age group,[3]imposing a significant burden on the healthcare system and society as a *** is related to frailty,which represents the dynamic progression of physical and physiological decline in older *** limits an individual’s ability to recover from acute stressors and serves as a predictor of clinical adverse *** the uncertainties in screening,assessing,and managing frailty in clinical practice,emphasizing the connections between frailty,aging,and CVD will provide new insights for the prediction,prevention and management of CVD in the aging population.

关键词： aging prevention prediction

Vegetation changes across the Eocene-Oligocene transition:Global signals *** development

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Science China Earth Sciences 2024年第9期67卷 2937-2952页

作者： Mengxiao wu Lutz KUNZMANN Shufeng li Vasilis TEODORIDIS Zhekun ZHOU tao SU CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China Senckenberg Natural History Collections Dresden Konigsbrücker LandstraBe 159Dresden 01109Germany Department of Biology and Environmental Studies Faculty of EducationCharles UniversityMagdalény Rettigové411639 Prague 1Czech Republic State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China

The Eocene-Oligocene transition(EOT)marked a rapid global cooling event,often considered as the beginning of the modern icehouse *** by various factors,including tectonic activity and paleogeographic settings,the terrestrial records indicate a diverse response of fauna and vegetation to this global *** examined nine macrofossil assemblages from seven fossil localities on the southeastern margin of the Tibetan Plateau and from the mid-latitudinal Europe ranging from the latest Bartonian and Priabonian(37.71-33.9 Ma)to the Rupelian(33.9-27.82 Ma).Our aims were to trace and compare the vegetation history of both regions in the late Eocene and early *** results show that both regions experienced changes in vegetation composition in response to climate change,characterized by a decrease in the percentages of broad-leaved evergreen elements and distinctive changes in general vegetation types.A general change in the overall vegetation type from subtropical broad-leaved evergreen forests in the late Eocene to temperate broad-leaved mixed deciduous evergreen forests,or mixed mesophytic forests,in the early Oligocene is recognized in both *** results indicate a clear change in leaf architecture,leaf margin states,and secondary venation types in the mid-latitudinal Europe,while the results from the southeastern margin of the Tibetan Plateau show a distinct reduction in leaf *** data suggest that both global and regional factors played key roles in shaping the vegetation in the two regions.

关键词： Eocene-Oligocene transition Plant fossil Paleoclimate Leaf architecture Biodiversity

An improved transfer learning strategy for short-term cross-building energy prediction usingdata incremental

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Building Simulation 2024年第1期17卷 165-183页

作者： Guannan li Yubei wu Chengchu Yan Xi Fang tao li Jiajia Gao Chengliang Xu Zixi Wang School of Urban Construction Wuhan University of Science and TechnologyWuhan 430065China Anhui Province Key Laboratory of Intelligent Building and Building Energy-saving Anhui Jianzhu UniversityHefei 230601China State Key Laboratory of Green Building in Western China Xi'an University of Architecture and TechnologyXi'an 710055China College of Urban Construction Nanjing Tech UniversityNo.200North Zhongshan RoadNanjing 210009China Key Laboratory of Low-grade Energy Utilization Technologies and Systems(Chongqing University) Ministry of Education of ChinaChongqing UniversityChongqing 400044China College of Civil Engineering Hunan UniversityChangsha 410082China Hubei Provincial Engineering Research Center of Urban Regeneration Wuhan University of Science and TechnologyWuhan 430065China

The available modelling data shortage issue makes it difficult to guarantee the performance of data-driven building energy prediction(BEP)models for both the newly built buildings and existing information-poor *** knowledge transfer learning(KTL)and data incremental learning(DIL)can address the data shortage issue of such *** new building scenarios with continuous data accumulation,the performance of BEP models has not been fully investigated considering the data accumulation ***,which can learn dynamic features from accumulated data adapting to the developing trend of new building time-series data and extend BEP model's knowledge,has been rarely *** studies have shown that the performance of KTL models trained with fixed data can be further improved in scenarios with dynamically changing ***,this study proposes an improved transfer learning cross-BEP strategy continuously updated using the coarse data incremental(CDI)*** hybrid KTL-DIL strategy(LSTM-DANN-CDI)uses domain adversarial neural network(DANN)for KLT and long short-term memory(LSTM)as the Baseline BEP *** evaluation is conducted to systematically qualify the effectiveness and applicability of KTL and improved ***-world data from six-type 36 buildings of six types are adopted to evaluate the performance of KTL and KTL-DIL in data-driven BEP tasks considering factors like the model increment time interval,the available target and source building data *** with LSTM,results indicate that KTL(LSTM-DANN)and the proposed KTL-DIL(LSTM-DANN-CDI)can significantly improve the BEP performance for new buildings with limited *** with the pure KTL strategy LSTM-DANN,the improved KTL-DIL strategy LSTM-DANN-CDI has better prediction performance with an average performance improvement ratio of 60%.

关键词： building energy prediction(BEP) cross-building data incremental learning(DIL) domain adversarial neural network(DANN) knowledge transfer learning(KTL)