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Attitude Coordination of Multi-HUG Formation Based on Multibody System Theory

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China Ocean Engineering 2017年第2期31卷 248-255页

作者： XUE dong-yang WU Zhi-liang QI Er-mai WANG Yan-hui WANG Shu-xin key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University Tianjin 300072 China School of Mechanical Engineering Tianjin University Tianjin 300072 China National Ocean Technology Center Tianjin 300112 China

Application of multiple hybrid underwater gliders （HUGs） is a promising method for large scale, long-term ocean survey. Attitude coordination has become a requisite for task execution of multi-HUG formation. In this paper, a multibody model is presented for attitude coordination among agents in the HUG formation. The HUG formation is regarded as a multi-rigid body system. The interaction between agents in the formation is described by artificial potential field （APF） approach. Attitude control torque is composed of a conservative torque generated by orientation potential field and a dissipative term related with angular velocity. Dynamic modeling of the multibody system is presented to analyze the dynamic process of the HUG formation. Numerical calculation is carried out to simulate attitude synchronization with two kinds of formation topologies. Results show that attitude synchronization can be fulfilled based on the multibody method described in this paper. It is also indicated that different topologies affect attitude control quality with respect to energy consumption and adjusting time. Low level topology should be adopted during formation control scheme design to achieve a better control effect.

关键词： hybrid underwater gliders (HUGs) formation attitude coordination multibody system Kane's equation

Theoretical Study on Resonance Raman Spectra of Tetraoxaporphyrin Dication by TDDFT Calculation

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Chinese Journal of Chemical Physics 2015年第5期28卷 -页

作者： Guo-bing Wang hui-qing Zhao Zhen-lin Zhang Wen-lou Wang dong-ming Chen Department of Chemical Physics University of Science and Technology of China Hefei 230026China Department of Chemistry College of Basic Medicine Anhui Medical University Hefei 230032 China

The B state excited resonance Raman scattering of tetraoxaporphyrin dication (TOP2+) was theoretically studied with DFT/TDDFT calculations and the sum-over-states approach of polarizability including both the A and B terms contributions. The resonance Raman spectra calculated with PBE1PBE, B3LYP, Cam-B3LYP, and B3LYP-D3 functionals are similar to each other in general, with PBE1PBE and B3LYP being better in reproducing resonance Raman intensities in comparison with the experiment. The calculated relative intensities of the totally symmetric modes are excellently consistent with the experiment. The TDDFT calculations manifested a considerable deformation of the B state along the ν2, ν6, ν7, and ν8 modes, which is responsible for the strong resonance Raman intensities of these modes. The resonance Raman intensities of non-totally symmetric modes were calculated to be weaker than the totally symmetric modes by one or two order of magnitude, which qualitatively agrees with the experiment. However, the resonance Raman intensity of the ν10 mode (CβCβ stretch, B1g symmetry) predicted by TDDFT calculations is unexpectedly small whereas that of the ν11 mode (symmetric CαCm stretch, B1g symmetry) is too large, which is assumed to be caused by the Jahn-Teller instability for the B state of TOP2+.

关键词： Tetraoxaporphyrin Resonance Raman TDDFT Excited state structure Franck-Condon mechanism

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某船用柴油机气马达传动轴断裂失效分析

内燃机与配件 2024年第7期 74-76页

作者：辛志刘云辉刘英超李晖张冬生潍柴动力股份有限公司山东潍坊261041

某项目开发过程中,气动马达的传动轴起动约25~30次时发生早期断裂故障。通过对使用工况、结构特点、硬度分析、金相分析等方面,分析了该气马达传动轴断裂失效的原因。分析结果表明:该传动轴的断裂模式为多源性疲劳断裂。主要原因为异常... 详细信息

某项目开发过程中,气动马达的传动轴起动约25~30次时发生早期断裂故障。通过对使用工况、结构特点、硬度分析、金相分析等方面,分析了该气马达传动轴断裂失效的原因。分析结果表明:该传动轴的断裂模式为多源性疲劳断裂。主要原因为异常冲击造成的传动轴花键根部产生初始裂纹,伴随着花键轴不合理的结构设计,不合理的热处理工艺等因素,导致裂纹逐步扩展,最终发展为断裂失效。

关键词：船用柴油机传动轴气动马达失效分析

Cementitious property of NaAlO2-activated Ge slag as cement supplement

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International Journal of Minerals,Metallurgy and Materials 2019年第12期26卷 1594-1603页

作者： Hua-zhe Jiao Shu-fei Wang Ai-xiang Wu hui-ming Shen Jian-dong Wang International Joint Research Laboratory of Henan Province for Underground Space Development and Disaster Prevention Henan Polytechnic UniversityJiaozuo 454000China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

Germanium(Ge),a waste residue leaching from zinc(Zn)smelting process,has potential cementitious properties and could be recycled as a cement supplement activated by chemical *** this work,a test was conducted to determine the hydration properties of Ge slag-cement-based composites with Ge slag(GS)/ordinary Portland cement(PC)contents of 0wt%,5wt%,10wt%,15wt%,20wt%,and 25wt% and water-to-binder ratio(w/b)of *** activators Ca(OH)2,AlCl3,NaAlO2,and Na2CO3 were mixed under 1wt%,2wt%,3wt%,and 4wt% dosages of GS *** composition and microstructure of the hydration products were investigated by the combined approaches of X-ray diffraction(XRD),thermogravimetry-differential scanning calorimetry(TG-DSC),scanning electron microscopy(SEM),and energy-dispersive X-ray spectroscopy(EDS).First,the GS cementitious property is attributed to the high content of CaSO4·***,the activators affected the acceleration performance in the following order:NaAlO2,Na2CO3,AlCl3,and Ca(OH)*** importantly,the 28-day unconfined compressive strength(UCS)is 45.34 MPa at the optimum formula of 0.6wt% NaAlO2,15wt% GS,and 85wt% PC,which is 9.16% higher than the ***,NaAlO2 is beneficial for the ettringite(AFt)generation,resulting in the C-S-H structure ***,the Zn^2+ residue inhibited the AFt formation,representing an important challenge to the strength growth with curing ***,the GS could be recycled as a supplement to the cement under the activator NaAlO2.

关键词： Ge slag from zinc process recycling activator cement supplements strength

^(18)F-FDG PET/CT代谢参数联合癌胚抗原对良恶性孤立性肺结节的诊断价值

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江苏医药 2024年第3期50卷 250-254,F0003页

作者：黄奇峰董科郭雅欣姜婷张倩倩郑勇金华市中心医院核医学科浙江321000

目的探讨^(18)F-氟代脱氧葡萄糖(FDG)PET/CT代谢参数联合癌胚抗原(CEA)对良恶性孤立性肺结节(SPN)的诊断价值。方法行^(18)F-FDG PET/CT检查的66例SPN患者,其中良性病变16例(良性病变组),恶性病变50例(恶性病变组),比较两组患者临床资料... 详细信息

目的探讨^(18)F-氟代脱氧葡萄糖(FDG)PET/CT代谢参数联合癌胚抗原(CEA)对良恶性孤立性肺结节(SPN)的诊断价值。方法行^(18)F-FDG PET/CT检查的66例SPN患者,其中良性病变16例(良性病变组),恶性病变50例(恶性病变组),比较两组患者临床资料及^(18)F-FDG PET/CT不同代谢参数。采用ROC曲线分析^(18)F-FDG PET/CT代谢参数及CEA对恶性SPN的诊断效能。结果良性病变组CEA、最大标准化摄取值(SUV_(max))、平均标准化摄取值(SUV_(mean))、峰值瘦体标准化摄取值(SUL_(peak))、糖酵解总量(TLG)、肿瘤-纵隔血池最大标准摄取值比(TMR)和肿瘤-正常肝最大标准摄取值比(TLR)均低于恶性病变组(P<0.05)。SUV_(max)+SUV_(mean)+SUL_(peak)+TLG+TLR+TMR+CEA诊断恶性SPN的AUC为0.890,诊断的灵敏度和特异度分别为82.0%和87.5%。结论^(18)F-FDG PET/CT代谢参数联合CEA对良恶性SPN有较好的诊断效能。

关键词：孤立性肺结节 ^(18)F-氟代脱氧葡萄糖正电子发射断层显像/计算机断层成像癌胚抗原

乳腺增生患者供血动脉血流参数与促血管新生因子表达及综合治疗疗效的相关性

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中国超声医学杂志 2024年第8期40卷 870-874页

作者：李夏李拓董莹南阳医学高等专科学校第一附属医院超声诊断科南阳医学高等专科学校医学技术系

目的探究乳腺增生患者超声测定乳腺供血动脉血流参数[收缩期峰值流速(PSV)、阻力指数(RI)]与促血管新生因子[血管内皮生长因子(VEGF)、碱性成纤维细胞生长因子(bFGF)]表达及综合治疗疗效的相关性。方法回顾性收集经病理证实的122例乳... 详细信息

目的探究乳腺增生患者超声测定乳腺供血动脉血流参数[收缩期峰值流速(PSV)、阻力指数(RI)]与促血管新生因子[血管内皮生长因子(VEGF)、碱性成纤维细胞生长因子(bFGF)]表达及综合治疗疗效的相关性。方法回顾性收集经病理证实的122例乳腺增生患者临床资料，统计对比不同病理类型、不同疗效乳腺增生患者入院次日(综合治疗前)PSV、RI及VEGF、bFGF水平，观察综合治疗前后指标变化。受试者工作特征(ROC)曲线分析治疗前PSV、RI、VEGF、bFGF对疗效的预测效能；Pearson分析评价治疗前PSV、RI与VEGF、bFGF的相关性。结果混合型与腺瘤样增生患者PSV、RI及血清VEGF、bFGF水平均显著大于囊性增生、小叶增生(P0.05)。乳腺增生患者治疗3个月后PSV、RI、血清VEGF及bFGF水平较治疗前均显著下降(P<0.05)。122例乳腺增生患者中，治疗显效率为83.61%(102/122),不佳率为16.39%(20/122)。治疗显效患者治疗前PSV[(9.75±2.20)cm/s vs.(11.25±2.33)cm/s]、RI(0.49±0.10 vs. 0.60±0.09)、血清VEGF[(206.95±27.07)ng/L vs.(240.58±43.65)ng/L]及bFGF[(42.94±8.13)ng/L vs.(50.00±12.01)ng/L]水平均显著低于不佳患者(P<0.05)。治疗前PSV、RI、VEGF、bFGF单一检测及其联合检测预测乳腺增生患者治疗显效的曲线下面积分别为0.717、0.802、0.721、0.676、0.933。乳腺增生患者治疗前PSV与VEGF、bFGF正相关(P<0.001),RI与VEGF、bFGF正相关(P<0.001)。结论乳腺增生患者乳腺供血动脉血流参数与促血管新生因子均呈正相关，检测结果对治疗效果有一定的预测价值，特别是联合检测。

关键词：乳腺增生彩色多普勒超声血流参数促血管新生因子疗效相关性

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提高铝板带材生产静电涂油质量的措施

有色金属加工 2024年第1期53卷 67-70页

作者：陈辉李文华董磊高立军洛阳万基铝加工有限公司河南洛阳471832

文章对铝板带生产中静电涂油机的组成和工作原理进行介绍,并对影响涂油质量的主要因素进行分析,提出了应对方法和设备改进措施,可为同行业相关设备性能提升提供技术参考。

关键词：涂油机刀梁高压静电雾化

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长白山天池火山含碳气体排放特征

地震 2024年第3期44卷 196-214页

作者：顾国辉盘晓东关升仲广培宋雨佳胡乐李营吉林省地震局吉林长白山火山国家野外科学观测研究站吉林长春130117 中国地震局火山研究所吉林长春130117 中国地震局地震预测研究所北京100036

查明火山气体释放的规模及空间分布特征,对火山监测与喷发预测、评估地质源温室气体释放及气候环境变化等具有重要意义。本文采用密闭气室法观测土壤气浓度,计算了长白山天池火山区CO_(2)和CH_(4)气体释放通量,结合高光谱气体CO和CO_(2... 详细信息

查明火山气体释放的规模及空间分布特征,对火山监测与喷发预测、评估地质源温室气体释放及气候环境变化等具有重要意义。本文采用密闭气室法观测土壤气浓度,计算了长白山天池火山区CO_(2)和CH_(4)气体释放通量,结合高光谱气体CO和CO_(2)分析了火山区不同区域气体释放特征及影响因素。结果表明:(1)长白山天池火山区土壤CO_(2)通量范围为0.16~1051.39 g·m^(-2)·d^(-1);CH_4通量值范围为-0.05~4.68 g·m^(-2)·d^(-1)。长白山天池火山区气体释放在空间上呈环带状分布特征,火山口周缘气体释放较弱,在聚龙温泉群、锦江温泉群和锥体海拔1800~2200 m范围内气体释放最为强烈。(2)长白山天池火山含碳气体释放在地表和高光谱卫星观测的时间和空间上都有一定的相关性,火山口上方气体释放最弱。(3)长白山天池火山含碳气体排放的空间差异可能受到火山口特殊条件、断裂构造、温泉地热储和岩浆作用的控制。

关键词：长白山天池火山气体通量高光谱气体空间特征控制因素

Comparative Study on the Expression of Genes Involved in Carotenoid and ABA Biosynthetic Pathway in Response to Salt Stress in Tomato

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Journal of Integrative Agriculture 2012年第7期11卷 1093-1102页

作者： DUAN hui-kun ZHU Yan QI dong-dong LI Wen-long HUA Xue-jun LIU Yong-xiu DENG Xin key Laboratory of Plant Resources Institute of Botany Chinese Academy of Sciences Beijing 100093 P.R. China Graduate University of Chinese Academy of Sciences Beijing 100049 P.R. China key Laboratory of Plant Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 P.R.China

Carotenoid biosynthetic pathway produces not only pigments that protect photosynthetic system against photo-oxidative damage, but also precursors of abscisic acid, the major hormone regulates stress responses. To understand the response of carotenoid biosynthetic pathway to salt stress, the expression of the genes involved in carotenoid and ABA biosynthesis were compared in cultivated tomato Solanum lycopersicon cv. Moneymaker and its relative wild genotype S. pimpinellifolium （PI365967） together with the contents of carotenoids and ABA. The results showed that 11 of the 15 genes investigated were up-regulated and four unaltered in Moneymaker after 5 h of salt stress; whereas only four genes were up-regulated, four unaltered, and seven down-regulated in PI365967 after stress. Further comparison revealed that 11 salinity-induced genes were expressed significantly lower in Moneymaker than in PI365967 under normal condition, and 8 of them were induced to similar levels after salt stress. In consistence, ABA level was doubled in Moneymaker but kept consistent in PI365967 after salt stress, though the contents of neoxanthin, violaxanthin, [3-carotene, lutein, and total carotenoids were kept unchanged in both species. Since it is known that PI365967 is more tolerant to salt stress than Moneymaker, we proposed that the constitutive high level of carotenoid and ABA biosynthetic pathway under normal growth condition could be benefit to PI365967 for establishing the early response to salt stress. In addition, CrtR-bl and CrtR-b2 that encode [3-carotenoid hydroxylases were the only genes in carotenoid biosynthetic pathway that were up-regulated by salt stress in both species. The CrtR-b2 gene was cloned from both species and no essential difference was found in the encoded amino acid sequences. Transformation of CrtR-b2 to tobacco improved the seed germination under salt stress condition, indicating that the hydrolysis of β-carotenoid is the target of transcriptional regulatio

关键词： ABA carotenoid biosynthetic pathway gene expression salt stress tomato