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FAST Observations of Four Comets to Search for the Molecular Line Emissions between 1.0 and 1.5 GHz Frequencies

Research in Astronomy and Astrophysics 2024年第10期24卷 130-140页

作者： Long-Fei Chen Chao-Wei Tsai jian-Yang Li Bin Yang Di Li Yan Duan Chih-Hao Hsia Zhichen Pan Lei Qian Donghui Quan xue-jian jiang Xiaohu Li Ruining Zhao Pei Zuo School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guiyang 550025China Research Center for Astronomical Computing Zhejiang LaboratoryHangzhou 311100China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 519082China Núcleo de Astronomía Facultad de Ingenieríay CienciasUniversidad Diego PortalesChile Department of Astronomy College of Physics and Electronic EngineeringQilu Normal UniversityJinan 250200China Department of Electronic and Optical Engineering Space Engineering UniversityBeijing 101416China Laboratory for Space Research Faculty of ScienceThe University of Hong KongHong Kong(SAR)China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

We used the Five-hundred-meter Aperture Spherical radio Telescope(FAST)to search for the molecular emissions in the L-band between 1.0 and 1.5 GHz toward four comets,C/2020 F3(NEOWISE),C/2020 R4(ATLAS),C/2021 A1(Leonard),and 67P/Churyumov-Gerasimenko during or after their perihelion *** of molecular transition lines fall in this low-frequency range,many attributed to complex organic or prebiotic *** conducted a blind search for the possible molecular lines in this frequency range in those comets and could not identify clear signals of molecular emissions in the *** several molecules have been detected at high frequencies of greater than100 GHz in comets,our results confirm that it is challenging to detect molecular transitions in the L-band frequency *** non-detection of L-band molecular lines in the cometary environment could rule out the possibility of unusually strong lines,which could be caused by the masers or non-LTE *** the line strengths are predicted to be weak,for FAST,using the ultra-wide bandwidth receiver and improving the radio frequency interference environments would enhance the detectability of those molecular transitions at low frequencies in the future.

关键词： astrochemistry ISM:molecules comets:general line:identification

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Evolutionary stages and disk properties of young stellar objects in the Perseus cloud

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Research in Astronomy and Astrophysics 2015年第8期15卷 1294-1324页

作者： Hong-Xin Zhang Yu Gao Min Fang Hai-Bo Yuan Ying-He Zhao Rui-Xiang Chang xue-jian jiang Xiao-Wei Liu A-Li Luo Hong-Jun Ma Zheng-Yi Shao Xiao-Long Wang National Astronomical Observatories Chinese Academy of Sciences Department of Astronomy Peking University Kavli Institute for Astronomy and Astrophysics Peking University Chinese Academy of Sciences South America Center for Astronomy Camino EI Observatorio #1515Las CondesSantiagoChile Instituto de Astrofísica Facultad de FísicaPontificia Universidad Católica de ChileAv.Vicuna Mackenna 48607820436 MaculSantiagoChile Purple Mountain Observatory Chinese Academy of Sciences Key Laboratory of Radio Astronomy Chinese Academy of Sciences Departamento de Física Teórica Universidad Autónoma de Madrid 28049 CantoblancoMadridSpain Infrared Processing and Analysis Center California Institute of TechnologyMS 100-22PasadenaCA 91125USA Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of Sciences

We investigated the evolutionary stages and disk properties of 211 young stellar objects（YSOs） across the Perseus cloud by modeling their broadband optical to mid-infrared（IR） spectral energy distribution（SED）. Our optical gri photometry data were obtained from the recently finished Purple Mountain Observatory Xuyi Schmidt Telescope Photometric Survey of the Galactic Anti-center（XSTPS-GAC）.About 81% of our sample fall into the Stage II phase which is characterized by having optically thick disks, while 14% into the Stage I phase characterized by having significant infalling envelopes, and the remaining 5% into the Stage Ⅲ phase characterized by having optically thin disks. The median stellar age and mass of the Perseus YSOs are 3.1 Myr and 0.3 M⊙ respectively. By exploring the relationships among the turnoff wave bands λturnoff（longward of which significant IR excesses above the stellar photosphere are observed）, the excess spectral index αexcess as determined for λ 〉 λturnoff, and the disk inner radius Rin（determined from SED modeling） for YSOs at different evolutionary stages, we found that the median and standard deviation of αexcess for YSOs with optically thick disks tend to increase withλturnoff, especially at λturnoff ≥5.8 μm, whereas the median fractional dust luminosities Ldust/L★ tend to decrease with increasing λturnoff. This points to an inside-out process of disk clearing for small dust grains. Moreover, a positive correlation between αexcess and Rin was found at α〉excess ～ 0 and R〉in～ 10 × the dust sublimation radius Rsub, irrespective of λturnoff, Ldust/L★ and disk flaring. This suggests that the outer disk flaring either does not evolve synchronously with the inside-out disk clearing of small dust grains or has little appreciable influence on the spectral slopes at λ〈～ 24 μm. About 23% of our YSO disks are classified as transitional disks, which haveλturnoff ≥ 5.8 μm and Ldust/L★ 〉 10-3. The transitional disks and full disks occupy distinctly differe

关键词： stars: formation—stars: low-mass—stars: pre-main sequence—individual: Perseus Cloud—circumstellar matter—protoplanetary

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同步电动机无源性控制方法

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上海交通大学学报 2008年第12期42卷 2015-2019页

作者：薛花姜建国上海交通大学电气工程系上海200240

利用本质上是非线性反馈控制的无源性控制方法,与非线性状态观测相结合,实现负载转矩时变未知情形下磁链、转速的渐近跟踪,并可有效抑制由转子状态的不确定性引起的跟踪误差.该方法从能量角度分析电动机控制系统,确定不必抵消的"无功力"... 详细信息

利用本质上是非线性反馈控制的无源性控制方法,与非线性状态观测相结合,实现负载转矩时变未知情形下磁链、转速的渐近跟踪,并可有效抑制由转子状态的不确定性引起的跟踪误差.该方法从能量角度分析电动机控制系统,确定不必抵消的"无功力",设计全局定义的控制律,具有形式简单、无奇异点、鲁棒性好等特点.基于dSPACE的实验结果证明了该控制策略的有效性.

关键词：无源性控制同步电动机自适应控制

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Mimicking aneurysm in a patient with chronic occlusion of the left middle cerebral artery

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World Journal of Clinical Cases 2025年第3期13卷 20-23页

作者： xue-jian Wang Department of Neurosurgery Affiliated Hospital 2 of Nantong UniversityNantong 226000Jiangsu ProvinceChina

The chronic occlusion of intracranial arteries generally has no or mild clinical symptoms,and the clinical symptoms of acute cerebral artery occlusion are mostly manifested as severe cerebral infarction symptoms,which often make early diagnosis difficult,thus losing the best treatment *** cerebral infarction occurs,the consequences are difficult to *** is also an important reason for the high misdiagnosis rate and mortality of this *** this paper,the characteristics of the disease were analyzed to provide clinical reference.

关键词： Chronic occlusion Misdiagnose Arterial occlusion Middle cerebral artery occlusion Aneurysm

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Real Time Simulation for 2-DOF Planar Robot Based Inverted Pendulum System

Real Time Simulation for 2-DOF Planar Robot Based Inverted P...

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2009中国控制与决策会议

作者： Feng PAN,Da Li CHEN,Ding Yu xue,jian jiang CUI Academy of Information Science and Engineering,NEU,Shen Yang,110004

＜正＞Based on system simulation technology of MATLAB/Simulink,this article establishes the system mathematical model by applying the mechanism modeling method;designs and implements the real time simulation system for inverted pendulum servo-control *** 2-DOF planar robot based inverted pendulum system is a multivariable,nonlinear and unstable actual controlled plant,which has been put in the simulation system loop for simulation study,including designing the system controller,building up the virtual instrument,monitoring the system operation in real-time,on-line and testing the system dynamic properties,this control result is good.

关键词： Inverted Pendulum Robot MATLAB/Simulink Optimizing Control Real Time Simulation

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Real-world evidence on the efficacy and safety of vonoprazanamoxicillin dual therapy for Helicobacter pylori treatment in elderly patients

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World Journal of Gastroenterology 2025年第1期31卷 68-78页

作者： Wen Gao Jing-Wen Li Hui Ye xue-Zhi Zhang jian-Xiang Liu Hong Cheng Department of Gastroenterology Peking University First HospitalBeijing 100034China School of Medicine Tsinghua MedicineTsinghua UniversityBeijing 100034China Department of Traditional Chinese Medicine and Integrative Medicine Peking University First HospitalBeijing 100034China

BACKGROUND A dual therapy regimen containing amoxicillin is a common treatment option for the eradication of Helicobacter pylori(***).While substantial research supports the efficacy and safety of vonoprazan and amoxicillin(VA)dual therapy in the general population,there is still a lack of studies specifically focusing on its safety in elderly *** To evaluate efficacy and safety of VA dual therapy as first-line or rescue treatment for *** in elderly *** As a real-world retrospective study,data were collected from elderly patients aged 60 years and above who accepted VA dual therapy(vonoprazan 20 mg twice daily+amoxicillin 1000 mg thrice daily for 14 days)for *** eradication in the Department of Gastroenterology at Peking University First Hospital between June 2020 and January *** status was evaluated by^(13)C-urease breath test 6 weeks after *** adverse events(AEs)during treatment were *** In total,401 cases were ***-one cases were excluded due to loss to follow-up,lack of re-examination,or unwillingness to take *** total of 380 included cases comprised 250 who received VA dual therapy as first-line treatment and 130 who received VA dual therapy as rescue *** was successfully eradicated in 239 cases(95.6%)in the first-line treatment group and 116 cases(89.2%)in the rescue treatment *** overall incidence of AEs was 9.5%for both ***,9.2%of patients experienced an AE in the first-line treatment group and 10.0%in the rescue treatment *** patients discontinued treatment due to AE,with a discontinuation rate of 1.3%.No serious AE *** The VA dual therapy regimen as a first-line treatment and a rescue therapy was effective and safe for elderly patients aged 60 and older.

关键词： Helicobacter pylori Vonoprazan Amoxicillin Dual therapy Elderly

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不同剂量置换液连续性血液净化治疗小儿呼吸窘迫综合征的临床疗效比较

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中国全科医学 2016年第30期19卷 3675-3680页

作者：熊道学姜建渝冯琰王玲成艳重庆三峡中心医院儿童重症医学科重庆市404000

目的比较常规剂量置换液与高剂量置换液连续性血液净化(CBP)治疗小儿呼吸窘迫综合征(ARDS)的临床疗效。方法选取2012—2015年重庆三峡中心医院儿童重症医学科(PICU)收治的符合纳入标准的ARDS患儿31例,按照随机数字表法分为常规剂量组15... 详细信息

目的比较常规剂量置换液与高剂量置换液连续性血液净化(CBP)治疗小儿呼吸窘迫综合征(ARDS)的临床疗效。方法选取2012—2015年重庆三峡中心医院儿童重症医学科(PICU)收治的符合纳入标准的ARDS患儿31例,按照随机数字表法分为常规剂量组15例及高剂量组16例。两组患儿均在常规机械通气等疗法基础上,采用连续性静-静脉血液透析滤过(CVVHDF)模式进行CBP治疗,常规剂量组给予常规剂量置换液(20~35 ml·kg^(-1)·h^(-1))治疗,高剂量组给予高剂量置换液(50~70 ml·kg^(-1)·h^(-1))治疗。以患儿死亡或转出PICU作为研究终点,观察两组患儿的治疗结果;比较两组患儿治疗前(治疗0 h)及治疗中(24、48、96、144 h)氧合指数(Pa O_2/Fi O_2)、p H值、动脉血氧分压(Pa O_2)、动脉血二氧化碳分压(Pa CO_2)、碱剩余(BE)、吸入氧浓度(Fi O_2)、呼吸频率、吸气峰压(PIP)、呼气末正压(PEEP)、潮气量(Vt),治疗120 h时小儿危重病例评分(PCIS)、第三代小儿死亡风险(PRISMⅢ)评分,CBP治疗时间、机械通气时间、入住PICU时间以及CBP治疗期间不良事件(包括寒战/低体温、低血压、高血压、滤器凝血、局部和/或全身出血)发生情况。结果两组患儿治疗好转率比较,差异无统计学意义(P=0.121)。剂量与时间在Pa O_2/Fi O_2、p H值、Pa O_2、Pa CO_2、BE、Fi O_2、呼吸频率、PIP、PEEP、Vt上不存在交互作用(P>0.05);剂量对Pa O_2/Fi O_2、Pa O2的主效应显著(P0.05);时间对Pa O_2/Fi O_2、p H值、Pa O_2、Pa CO_2、BE、Fi O_2、呼吸频率、PIP、PEEP、Vt的主效应显著(P0.05)。常规剂量组患儿共进行65例次CBP治疗,高剂量组患儿共进行72例次CBP治疗;高剂量组患儿寒战/低体温、低血压、高血压发生率高于常规剂量组,滤器凝血率低于常规剂量组(P0.05)。结论在CBP治疗早期,高剂量置换液较常规剂量置换液改善ARDS患儿氧合情况存在一定优越性,但综合患儿临床结果、入住PICU时间及CBP治疗期间不良事件等因素,临床选择尚需根据患儿实际情况而定。

关键词：呼吸窘迫综合征血液透析滤过剂量效应关系疗效比较研究

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分子电子学与分子电子器件

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山东大学学报（理学版） 2002年第4期37卷 339-342页

作者：张宏川崔学桂姜建壮山东大学化学与化工学院济南250100

介绍了分子电子学与分子器件研究领域的最新进展 ,展望了分子电子学的发展前景。

关键词：分子电子学分子电子器件研究进展分子导线分子开关分子整流器纳米电子学

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Preparation of Co/S co-doped carbon catalysts for excellent methylene blue degradation

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 169-181页

作者： Haixu Li Haobo He Tiannan jiang Yunfei Du Zhichen Wu Liang Xu Xinjie Wang Xiaoguang Liu Wanhua Yu Wendong xue School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Beijing Jinyu Tongda Refractory Technologies Co. Ltd.Beijing 100085China

S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB)*** effects of two different mixing routes were identified on the MB degradation ***,the catalyst obtained by the alcohol solvent evaporation(MOF-AEP)mixing route could degrade 95.60%MB(50 mg/L)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(MOF-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the Co-S content of MOF-AEP(43.39at%)was less than that of MOF-DGP(54.73at%),and the proportion of C-S-C in MOF-AEP(13.56at%)was higher than that of MOF-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PMS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PMS compared with ***,the degradation parameters,including pH and MOF-AEP dosage,were ***,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB.

关键词： advanced oxidation process alcohol solvent evaporation hydrogen bond S and Co co-doped carbon catalysts wastewater remediation

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黏液型铜绿假单胞菌临床分布与耐药性分析

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中华医院感染学杂志 2017年第12期27卷 2645-2648页

作者：李代昆李具琼余雪梅蔡伟薛建江重庆医科大学附属大学城医院检验科重庆401331

目的为临床合理使用抗菌药物治疗黏液型铜绿假单胞菌感染提供必要的病原学依据。方法收集医院2012年1月-2016年12月临床分离的86株黏液型铜绿假单胞菌感染病例,通过查阅病历获得患者一般资料、疾病情况、抗菌药物使用等信息,回顾性分析... 详细信息

目的为临床合理使用抗菌药物治疗黏液型铜绿假单胞菌感染提供必要的病原学依据。方法收集医院2012年1月-2016年12月临床分离的86株黏液型铜绿假单胞菌感染病例,通过查阅病历获得患者一般资料、疾病情况、抗菌药物使用等信息,回顾性分析黏液型铜绿假单胞菌的临床分布、耐药性及疗效。结果临床送检标本共分离出黏液型铜绿假单胞菌86株,男性占72.09%,女性占27.01%;老年人占83.72%,中年人占12.79%,青年人占3.49%;肺部感染、泌尿系感染和创伤感染分别占93.02%、3.49%和3.49%;氨苄西林/舒巴坦和磺胺甲噁唑/甲氧苄啶的耐药率为98.84%、95.35%,替卡西林和替卡西林/克拉维酸的耐药率为22.09%、13.95%,哌拉西林和哌拉西林/他唑巴坦的耐药率为11.63%和10.47%;疗效显著的病例占83.72%。结论黏液型铜绿假单胞菌感染主要集中在老年男性的呼吸道感染,临床应根据药敏结果合理选用抗菌药物。

关键词：黏液型铜绿假单胞菌临床分布耐药性疗效

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