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Optical Transient Source AT2021lfa:A Possible“Dirty Fireball”

Research in Astronomy and Astrophysics 2024年第4期24卷 124-133页

作者： Xue-Mei Ye Da-ming Wei yi-ming zhu Zhi-Ping Jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China

AT2021lfa,also known as ZTF21aayokph,was detected by the Zwicky Transient Facility on 2021 May 4,a 05:34:48 ***-up observations were conducted using a range of ground-based optical telescopes,as wel as Swift/XRT and VLA ***2021lfa is classified as an“orphan afterglow”candidate due to its rapid flux decline and its reddened color(g-r=0.17±0.14 mag).For an optical transient source without promp gamma-ray detection,one key point is to determine its burst *** we measure the burst time through fitting the initial bump feature of AT2021lfa and obtain its burst time as 2021 May 3,at 22:09:50 *** afterglowpy,we model the multi-band afterglow of AT2021lfa and find that the standard model canno reproduce the late radio observations *** that the microphysical parameters ε_(e),ε_(B)(the energy fraction given to electrons and magnetic field),andξN(the fraction of accelerated electrons)may vary with time we then model the afterglow of AT2021lfa taking into account the temporal evolution of the physical parameters ε_(e),ε^(B),and ξ_(N) and find in this case the multi-wavelength observations can be reproduced *** initial Lorentz factor of AT2021lfa can be estimated from the peak time of the early afterglow,which yields a value of about 18 suggesting that AT2021lfa should be classified as a“dirty fireball.”From the upper limit for the prompt emission energy of AT2021lfa,we obtain that the radiation efficiency is less than 0.02%,which is much smaller than that of ordinary gamma-ray bursts(GRBs).It is also interesting that the fitted values of jet angle and viewing angle are very large,θ_(c)~0.66 rad,θ_(v)~0.53 rad,which may lead to the low Lorentz factor and radiation *** compared with GRB afterglow samples,it is evident that the onset bump timescale of AT2021lfa satisfies the empirical relationships observed in GRB ***,the luminosity of AT2021lfa falls within the range of observations for GRB samples;howeve

关键词： gamma-rays:ISM methods:numerical radiation mechanisms:non-thermal

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Isocyanide-Based One-Pot Cascade Synthesis of 3-Acyl Isoindolinones

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Chinese Journal of Chemistry 2024年第3期42卷 259-263页

作者： Jia Liu yi-ming zhu Xiao-Ping Xu Shun-Jun Ji Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials Science & Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow UniversitySuzhouJiangsu215123 China Suzhou Baolidi Functional Materials Research Institute SuzhouJiangsu215144 China

A series of 3-acyl-substituted isoindolinone derivatives were synthesized in a one-pot manner via the reaction of o-bromobenzaldehydes,isocyanides,and carboxylic acids in the presence of palladium catalyst and base. The reaction employing easily available starting materials features simple operation and high efficiency. The mechanistic study showed that the reaction might undergo 1) Pd-catalyzed [3+2] cyclization of o-bromobenzaldehyde with isocyanide and the re-insertion of another molecule of isocyanide,2) addition of carboxylic acid to in situ formed ketenimine followed by a rearrangement relay to give 3,3-diacyl-substituted isoindolinone derivative. Further transformations of the obtained products through decarbonylation could also be realized.

关键词： One-pot reaction Isocyanide Pd catalysis Rearrangement reaction Isoindolinone

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Mn(Ⅲ)-mediated radical reaction of 2-isocyano-6-alkenyl(alkynyl)benzonitriles with arylboronic acids:Synthesis of pyrroloisoquinoline derivatives

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Chinese Chemical Letters 2021年第1期32卷 413-416页

作者： Pei Xu yi-ming zhu Xin-Yu Liu Xiao-Zhou Zhou Shun-yi Wang Shun-Jun Ji Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials Science&Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow UniversitySuzhou 215123China

A Mn(Ⅲ) mediated radical reaction of new designed multi-functionalized 2-isocyano-6-alkenyl(alkynyl)benzonitriles with arylboronic acids has been *** reaction provides a method for the synthesis of pyrroloisoquinolin... 详细信息

关键词： 2-Isocyano-6-alkenyl(alkynyl)benzonitriles Arylboronic acids Pyrroloisoquinoline derivatives Radical reaction

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Photoproduction reactionγn→K^(*0)∧in an effective Lagrangian approach

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Chinese Physics C 2022年第2期46卷 57-61页

作者： Neng-Chang Wei yi-ming zhu Fei Huang School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 101408China School of Physical Sciences University of Chinese Academy of SciencesBeijing 101408China

In our previous work[***.C 101,014003(2020)],the photoproduction reactionγp→K^(*+)Λwas investigated within an effective Lagrangian *** reaction amplitudes were constructed by including the t-channel K,K^(*),and k exchanges,u-channelΛ,∑,and∑^(*)exchanges,s-channel N,N(2000)5/2^(+),and N(2060)5/2^(-)exchanges,and interaction *** data on the differential cross sections and spin density matrix elements were described *** this study,we investigate the photoproduction reactionγn→K^(*0)Λbased on the same reaction mechanism as that ofγp→K^(*+)Λto obtain a unified description of the data forγp→K^(*+)Λandγn→K^(*0)Λwithin the same *** hadronic coupling constants,form factor cutoffs,and the resonance masses and widths in the present calculations remain the same as in our previous work forγp→K^(*+)Λ.The available differential cross-section data forγn→K^(*0)Λare well *** analysis shows that the cross sections ofγn→K^(*0)Λare dominated by the contributions of the t-channel K exchange,while the s-channel N(2000)5/2+and N(2060)5/2-exchanges also provide considerable contributions.

关键词： photoproduction effective Lagrangian approach gauge invariance

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Resonances Characteristics of Parallel Plate Waveguide Cavities

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Journal of Electronic Science and Technology 2015年第2期13卷 122-129页

作者： Lin Chen Dan-Ni Wang yi-ming zhu Yan Peng Shanghai Key Lab of Modern Optical System Engineering Research Center of Optical Instrument and SystemMinistry of EducationUniversity of Shanghai for Science and Technology

The influence of air gaps on the response of transmission for a transverse-electric mode parallel-plate waveguide（TE-PPWG） with a single cavity and double cavities has been studied experimentally. As the air gap is larger than the resonant wavelength of high order cavity mode in the single deep grooved waveguide, only the fundamental cavity mode can be excited and single resonance can be observed in the transmission spectrum. Based on above observations, a tunable multiband terahertz（THz）notch filter has been proposed and the variation of air gap has turned out to be an effective method to select the band number. Experimental data and simulated results verify this band number tunability. This mechanical control mechanism for electromagnetic induced transparency（EIT） will open a door to design the tunable THz devices.

关键词： resonant transparency excited waveguide tunable terahertz verify notch realization optics

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Terahertz time-domain spectroscopy and micro-cavity components for probing samples: a review

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Frontiers of Information Technology & Electronic Engineering 2019年第5期20卷 591-607页

作者： Lin CHEN Deng-gao LIAO Xu-guang GUO Jia-yu ZHAO yi-ming zhu Song-lin zhuANG Shanghai Key Lab of Modern Optical System University of Shanghai for Science and Technology Shanghai 200093 China Shanghai Cooperation Innovation Centre of Terahertz Spectroscopy and Imaging Technology Shanghai 200093 China Cooperative Innovation Center of Terahertz Science University of Electronic Science and Technology Chengdu 611731 China

We give a brief review of the developments in terahertz time-domain spectroscopy(THz-TDS) systems and microcavity components for probing samples in the University of Shanghai for Science and Technology. The broadband terahertz(THz) radiation sources based on GaAs m-i-n diodes have been investigated by applying high electric fields. Then, the free space THz-TDS and fiber-coupled THz-TDS systems produced in our lab and their applications in drug/cancer detection are introduced in detail. To further improve the signal-to-noise ratio(SNR) and enhance sensitivity, we introduce three general micro-cavity approaches to achieve tiny-volume sample detection, summarizing our previous results about their characteristics, performance, and potential applications.

关键词： Terahertz (THz) time-domain spectroscopy Micro-cavity Metal holes array Waveguide cavities Spoof localized surface plasmons (LSPs)

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Selective impairment of musical emotion recognition in patients with amnesic mild cognitive impairment and mild to moderate Alzheimer disease

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Chinese Medical Journal 2019年第19期132卷 2308-2314页

作者： Shan-Shan Zhou Xin Gao Ya-Juan Hu yi-ming zhu Yang-Hua Tian Kai Wang Department of Neurology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022China Department of Neurology The First People's Hospital of JiujiangJiujiangJiangxi 332000China Collaborative Innovation Centre of Neuropsychiatric Disorders and Mental Health HefeiAnhui 230032China Department of Medical Psychology Anhui Medical UniversityHefeiAnhui 230032China

Background:Patients with Alzheimer disease(AD)and amnesic mild cognitive impairment(aMCI)have deficits in emotion ***,it has not yet been determined whether patients with AD and aMCI also experience difficulty in recognizing the emotions conveyed by *** study was conducted to investigate whether musical emotion recognition is impaired or retained in patients with AD and ***:All patients were recruited from the First Affiliated Hospital of Anhui Medical University between March 1,2015 and January 31,*** the musical emotion recognition test,patients with AD(n=16),patients with aMCI(n=19),and healthy controls(HCs,n=16)were required to choose one of four emotional labels(happy,sad,peaceful,and fearful)that matched each musical *** recognition scores in three groups were compared using one-way analysis of variance(ANOVA)*** also investigated the relationship between the emotion recognition scores and Mini-Mental State Examination(MMSE)using Pearson’s correlation analysis test in patients with AD and ***:Compared to the HC group,both of the patient groups showed deficits in the recognition of fearful musical emotions(HC:7.88±1.36;aMCI:5.05±2.34;AD:3.69±2.02),with results of a one-way ANOVA confirming a significant main effect of group(F(2,50)=18.70,P<0.001).No significant differences were present among the three groups for the happy(F(2,50)=2.57,P=0.09),peaceful(F(2,50)=0.38,P=0.09),or sad(F(2,50)=2.50,P=0.09)musical *** recognition of fearful musical emotion was positively associated with general cognition,which was evaluated by MMSE in patients with AD and aMCI(r=0.578,P<0.001).The correlations between the MMSE scores and recognition of the remaining emotions were not significant(happy,r=0.228,P=0.11;peaceful,r=0.047,P=0.74;sad,r=0.207,P=0.15).Conclusion:This study showed that both patients with AD and aMCI had decreased ability to distinguish fearful emotions,which might be correlated with diminis

关键词： Mild cognitive impairment Alzheimer disease Musical emotion Melody recognition Brain network

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氢燃料电池用气浮离心空压机实验与模拟研究

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风机技术 2024年第3期66卷 29-34页

作者：李栋王琪杨山举张丽君祝艺鸣朱学卫西北农林科技大学机械与电子工程学院

气浮轴承离心空压机具有无油、高效、低成本、轻量化和动态响应性好等优点,已成为车载氢燃料电池空压机的最佳选择。本文介绍了自主研发的额定压比2.8、质量流量130g/s、转速88000r/min、功率22kW的两级气浮轴承离心空压机,用于匹配电... 详细信息

气浮轴承离心空压机具有无油、高效、低成本、轻量化和动态响应性好等优点,已成为车载氢燃料电池空压机的最佳选择。本文介绍了自主研发的额定压比2.8、质量流量130g/s、转速88000r/min、功率22kW的两级气浮轴承离心空压机,用于匹配电堆功率130kW的车载氢燃料电池。在离心空压机气动性能试验台上测试了空压机在60000~95000r/min范围内的气动性能,同时构建了离心空压机的泄漏通流模型并对其进行了数值模拟,最后将模拟结果与实验数据进行了对比分析。研究结果表明,该离心空压机在实验时最大转速达95000r/min,最大绝热效率可达77.04%。

关键词：氢燃料电池离心空压机箔片动压气浮轴承实验研究泄漏通流模型可靠性

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Surgery for Ectopic Parathyroid Adenoma in Lower Part of Superior Mediastinum through a Transcervical Incision

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Chinese Medical Journal 2017年第11期130卷 1376-1377页

作者： Xing Wang yi-ming zhu Hui Huang Li-Peng Zhang Ye Zhang Xiao-Lei Wang Department of Head-neck Surgery National Cancer Center/Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100021 China

INTRODUCTION Ectopically located hyperfunctioning parathyroid gland（s） are responsible for approximately 6-16% ofhyperparathyroidism cases, in which about 6% can be ascribed to ectopic growth in the mediastinal site. Treatment ofectopic adenomas usually requires resection. There are various techniques to resect ectopic parathyroid glands, which are mainly depended on the ectopic gland＇s location. However, choosing the correct type of treatment for cases can be difficult since there are no commonly accepted guidelines for treatment selection.

关键词： Ectopic Parathyroid Adenoma Superior Mediastinum Surgery

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Photocatalytic in situ H_(2)O_(2) production and activation for enhanced ciprofloxacin degradation over CeO_(2)-Co_(3)O_(4)/g-C_(3)N_(4):key role of CeO_(2)

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Rare Metals 2024年第6期43卷 2695-2707页

作者： Hong-Jie zhu yi-Kai Yang ming-Hui Li Lu-Ning Zou Hai-Tao Zhao Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry and Chemical Engin College of Ecology and Environment Anhui Normal UniversityWuhu241002China Liaocheng yiLu Advanced Materials Co. LtdLiaocheng 252000China

The abused ciprofloxacin antibiotics have caused significant environmental *** oxidative degradation of ciprofloxacin exhibits promising efficacy,it often entails excessive energy ***,it is necessary to explore an effective and ecologically sustainable degradation ***,we demonstrated that g-C_(3)N_(4) decorated with the coordinated CeO_(2)and Co_(3)O_(4)(CeO_(2)-Co_(3)O_(4)/CN)exhibited effective ciprofloxacin photodegradation via in situ H_(2)O_(2) production and activation *** indicate that the introduced CeO_(2) enhances the transference of photogenerated electrons to O_(2) by adjusting the oxygen vacancy of photocatalyst,thereby increasing the generation of superoxide radicals,which in turn generate H_(2)O_(2),resulting in a 22.4-fold increase in H_(2)O_(2) generation over g-C_(3)N_(4).Moreover,the in situ H_(2)O_(2)generation facilitated by CeO_(2) is confirmed to be essential for ciprofloxacin degradation via CeO_(2)-Co_(3)O_(4)/CN,as it provides enough oxidant for Co_(3)O_(4) to activate into hydroxyl radicals for the pollutants ***,CeO_(2)-Co_(3)O_(4)/CN achieves a ciprofloxacin degradation ratio of 97.7%within 80 *** study introduces a novel approach that combines H_(2)O_(2) generation and activation,offering an innovative perspective for achieving clean and efficient purification of antibiotic-contaminated water.

关键词： CeO_(2) In situ H_(2)O_(2)generation Ciprofloxacin degradation Photocatalyst

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