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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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Toward a Direct Measurement of the Cosmic Acceleration: The Pilot Observation of HI 21 cm Absorption Line at FAST

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Research in Astronomy and Astrophysics 2024年第7期24卷 50-58页

作者： Jiangang Kang Chang-Zhi Lu Tong-Jie Zhang ming zhu Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University School of Physics and Astronomy Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences

This study presents results on detecting neutral atomic hydrogen（H I） 21 cm absorption in the spectrum of PKS PKS1413+13 at redshift z = 0.24670041. The observation was conducted by FAST, with a spectral resolution of10 Hz, using 10 minutes of observing time. The global spectral profile is examined by modeling the absorption line using a single Gaussian function with a resolution of 10 kHz within a 2 MHz bandwidth. The goal is to determine the rate of the latest cosmic acceleration by directly measuring the redshift evolution of the H I 21 cm absorption line with Hubble flow toward a common background quasar over a decade or longer time span. This will serve as a detectable signal generated by the accelerated expansion of the Universe at redshift z < 1, referred to as redshift drift z（5） or the SL effect. The measured H I gas column density in this DLA system is approximately equivalent to the initial observation value, considering uncertainties of the spin temperature of a spiral host galaxy. The high signal-to-noise ratio of 57,obtained at a 10 kHz resolution, strongly supports the feasibility of using the H I 21 cm absorption line in DLA systems to accurately measure the redshift drift rate at a precision level of around 10-10per decade.

关键词： (cosmology:) cosmological parameters (cosmology:) dark energy cosmology: observations cosmology: theory ISM: clouds radio lines: galaxies radio lines: ISM

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Fe-N_(x) sites coupled with core-shell FeS@C nanoparticles to boost the oxygen catalysis for rechargeable Zn-air batteries

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Journal of Energy Chemistry 2024年第3期90卷 565-577,I0013页

作者： Katam Srinivas zhuo Chen Anran Chen Fei Ma ming-qiang zhu Yuanfu Chen School of Integrated Circuit Science and Engineering and State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and Technology of ChinaChengdu 610054SichuanChina College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100ShaanxiChina School of Materials and Energy Yunnan UniversityKunming 650091YunnanChina

The development of efficient single-atom catalysts(SACs) for the oxygen reduction reaction(ORR)remains a formidable challenge,primarily due to the symmetric charge distribution of metal singleatom sites(M-N_(4)).To address such issue,herein,Fe-N_(x) sites coupled synergistic catalysts fabrication strategy is presented to break the uniform electronic distribution,thus enhancing the intrinsic catalytic ***,atomically dispersed Fe-N_(x) sites supported on N/S-doped mesoporous carbon(NSC)coupled with FeS@C core-shell nanoparticles(FAS-NSC@950) is synthesized by a facile hydrothermal reaction and subsequent *** to the presence of an in situ-grown conductive graphitic layer(shell),the FeS nanoparticles(core) effectively adjust the electronic structure of single-atom Fe sites and facilitate the ORR kinetics via short/long-range coupling ***,FAS-NSC@950displays a more positive half-wave potential(E_(1/2)) of 0.871 V with a significantly boosted ORR kinetics(Tafel slope=52.2 mV dec^(-1)),outpacing the commercial Pt/C(E_(1/2)=0.84 V and Tafel slope=54.6 mV dec^(-1)).As a bifunctional electrocatalyst,it displays a smaller bifunctional activity parameter(ΔE) of 0.673 V,surpassing the Pt/C-RuO_(2) combination(ΔE=0.724 V).Besides,the FAS-NSC@950-based zincair battery(ZAB) displays superior power density,specific capacity,and long-term cycling performance to the Pt/C-Ir/C-based *** work significantly contributes to the field by offering a promising strategy to enhance the catalytic activity of SACs for ORR,with potential implications for energy conversion and storage technologies.

关键词： Fe-N_(x)sites Core-shell FeS@C Synergistic interactions Oxygen reduction reaction Zn-air battery

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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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Hydrogen Bonds in Perovskite for Efficient and Stable Photovoltaic

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Chinese Journal of Chemistry 2024年第11期42卷 1284-1306页

作者： Tian-yun Wang Yang-yang Hao ming-zhe zhu Guo-rui Cao Zhong-min Zhou College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdaoShandong266042 China College of Chemical Engineering Qingdao University of Science and TechnologyQingdaoShandong266042 China

Owing to their distinctive optical and physical properties,organic-inorganic hybrid perovskite materials have gained significant attention in the field of electronic devices,especially solar *** achievement of high-performance solar cells hinges upon the utilization of top-notch perovskite thin ***,the fabrication process involving solutions and the polycrystalline nature of perovskite result in the emergence of numerous defects within the perovskite films,consequently exerting a deleterious influence on the overall performance and stability of the *** the performance and stability of perovskite solar cells by additive engineering to suppress/passivate defects is a viable approach,which involves hydrogen bond interactions in these device engineering *** review explores the intrinsic hydrogen bonds in methylammonium and formamidium lead triiodide,while also considering cation rotations,phase transitions,and ***,the review classifies additives into distinct categories,including organic small molecules,polymers,nanodots,classical salts,ionic liquids,and molten *** various forms and characterization techniques of hydrogen bonds are discussed,as well as their potential synergistic effects in conjunction with other chemical ***,this review offers insights into the potential utilization of hydrogen bonds to further enhance the performance and stability of devices.

关键词： Perovskite solar cells Hydrogen bond Additive Performance Stability Charge transfer Inhibition Cooperative effects

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Efficacy of Huoxue Qianyang Qutan Recipe on essential hypertension:A randomized,double-blind,placebo-controlled trial

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Journal of Integrative Medicine 2024年第4期22卷 484-492页

作者： Jun Xie Yu-long Ma ming-tai Gui Lei Yao Jian-hua Li ming-zhu Wang Xun-jie Zhou Yi-fan Wang ming-yi Zhao Hui Cao Bo Lu De-yu Fu Department of Cardiology Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China Shanghai University of Traditional Chinese Medicine Shanghai 200120China

Background:Hypertension,a prevalent disease,is a significant risk factor for coronary heart *** Qianyang Qutan Recipe (HQQR),a traditional Chinese herbal remedy,has been used for treating hypertension over several ***:This study assesses HQQR’s efficacy for controlling blood pressure among patients with hypertension related to blood stasis,yang hyperactivity and ***,setting,participants and interventions:A randomized controlled trial was conducted at the Yueyang Hospital of Integrated Traditional Chinese and Western Medicine,Shanghai University of Traditional Chinese Medicine,China,from July 2020 to June *** components of HQQR were identified using thin-layer chromatography and high-performance liquid *** aged18–80 years,exhibiting traditional Chinese medicine syndromes of blood stasis,yang hyperactivity or phlegm,along with grades 1 or 2 hypertension,were randomly categorized into two *** intervention group was given HQQR granules alongside conventional hypertension treatment,while the control group was given placebo granules in addition to conventional treatment for 12 *** outcome measures:The primary outcome was clinic blood pressure,whereas secondary outcomes included metabolic indices (e.g.,homeostasis model assessment of insulin resistance[HOMA-IR],total cholesterol[TC],low-density lipoprotein cholesterol and triglyceride),target organ damage indices (left ventricular mass index and urinary albumin creatinine ratio[UACR]) and inflammation indices(interleukin-6[IL-6]and high-sensitivity C-reactive protein[hs-CRP]).Results:HQQR’s primary components were identified as salvianolic acid B,emodin and ferulic *** the 216 participants (108 in each group),compared to the control,the intervention group exhibited significant improvements (P<0.001) in clinic systolic blood pressure ([136.24±7.63]vs[130.06±8.50]mmHg),clinic diastolic blood pressure ([84.34±8.72]vs[80.46±6.05]mmHg),home systol

关键词： Huoxue Qianyang Qutan Recipe Hypertension Target organ damage Glycolipid metabolism Inflammatory Chinese herbal compound

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Surface diffraction beamline at the SSRF

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Nuclear Science and Techniques 2024年第7期35卷 47-57页

作者： Yue-Liang Gu Xu Zheng Xing-Min Zhang Bin Zhao Guang-Zhi Yin Da-ming zhu Yuan-He Sun Xing-Yu Gao Xiao-Long Li Shanghai Advanced Research Institute Chinese Academy of Sciences239 Zhangheng RoadPudong DistrictShanghai201204China

BL02U2 of the Shanghai Synchrotron Radiation Facility is a surface diffraction beamline with a photon flux of 5.5×10^(12) photons/s at 10 keV and a beam size of 160µm×80µm at the sample *** is dedicated to studying surfaces(solid-vacuum,solid-gas)and interfaces(solid-solid,solid-liquid,and liquid-liquid)in nanoscience,condensed matter,and soft matter systems using various surface scattering techniques over an energy range of 4.8-28 keV with transmission and reflection ***,BL02U2 has a high energy resolution,high angular resolution,and low beam divergence,which can provide excellent properties for X-ray diffraction experiments,such as grazing incident X-ray diffraction,X-ray reflectivity,crystal truncation rods,and liquid X-ray *** of in situ environments can also be provided for the samples *** paper describes the setup of the new beamline and its applications in various fields.

关键词： Surface and interface Beamline Surface diffraction Microstructure

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NbN quantum dots anchored hollow carbon nanorods as efficient polysulfide immobilizer and lithium stabilizer for Li-S full batteries

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Journal of Energy Chemistry 2024年第1期88卷 260-271,I0007页

作者： Fei Ma zhuo Chen Katam Srinivas Ziheng Zhang Yu Wu Dawei Liu Hesheng Yu Yue Wang Xinsheng Li ming-qiang zhu Qi Wu Yuanfu Chen School of Integrated Circuit Science and Engineering and State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and TechnologyChengdu 610054SichuanChina College of Science and Institute of Oxygen Supply Center of Tibetan Studies(Everest Research Institute)Tibet UniversityLhasa 850000TibetChina College of Mechanical and Electronic Engineering Northwest A&F UniversityXianyang 712100ShaanxiChina

The shuttle effect of lithium polysulfides(LiPSs)and uncontrollable lithium dendrite growth seriously hinder the practical application of lithium-sulfur(Li-S)*** simultaneously address such issues,monodispersed Nb N quantum dots anchored on nitrogen-doped hollow carbon nanorods(NbN@NHCR)are elaborately developed as efficient Li PSs immobilizer and Li stabilizer for high-performance Li-S full *** functional theory(DFT)calculations and experimental characterizations demonstrate that the sulfiphilic and lithiophilic NbN@NHCR hybrid can not only efficiently immobilize the soluble Li PSs and facilitate diffusion-conversion kinetics for alleviating the shuttling effect,but also homogenize the distribution of Li+ions and regulate uniform Li deposition for suppressing Li-dendrite *** a result,the assembled Li-S full batteries(NbN@NHCR-S||Nb N@NHCR-Li)deliver excellent long-term cycling stability with a low decay rate of 0.031%per cycle over 1000 cycles at high rate of 2 *** at a high S loading of 5.8 mg cm^(-2)and a low electrolyte/sulfur ratio of 5.2μL mg^(-1),a large areal capacity of 6.2 mA h cm^(-2)can be achieved in Li-S pouch cell at 0.1 *** study provides a new perspective via designing a dual-functional sulfiphilic and lithiophilic hybrid to address serious issues of the shuttle effect of S cathode and dendrite growth of Li anode.

关键词： Dual-functional host NbN quantum dots Shuttle effect Dendrite-free Li anode Li-S full batteries

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Tumor recurrence and survival prognosis in patients with advanced gastric cancer after radical resection with radiotherapy and chemotherapy

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1660-1669页

作者： Shuang-Fa Nie Chen-Yang Wang Lei Li Cheng Yang Zi-ming zhu Jian-Dong Fei Department of General Surgery The First Affiliated Hospital of Hebei North UniversityZhangjiakou 75000Hebei ProvinceChina Department of Gastrointestinal Surgery Zhongshan Hospital of Fudan UniversityShanghai 200032China

BACKGROUND Advanced gastric cancer is a common malignancy that is often diagnosed at an advanced stage and is still at risk of recurrence after radical surgical ***,as one of the important treatment methods for gastric cancer,is of great significance for improving the survival rate of ***,the tumor recurrence and survival prognosis of gastric cancer patients after radio-therapy and chemotherapy are still *** To analyze the tumor recurrence after radical radiotherapy and chemotherapy for advanced gastric cancer and provide more in-depth guidance for *** A retrospective analysis was performed on 171 patients with gastric cancer who received postoperative adjuvant radiotherapy and chemotherapy in our hospital from 2021 to *** Kaplan-Meier method was used to calculate the recurrence rate and survival rate;the log-rank method was used to analyze the single-factor prognosis;and the Cox model was used to analyze the prognosis associated with multiple *** The median follow-up time of the whole group was 63 months,and the follow-up rate was 93.6%.Stage II and III patients accounted for 31.0%and 66.7%,*** incidences of Grade 3 and above acute gastrointestinal reactions and hematological adverse reactions were 8.8%and 9.9%,respectively.A total of 166 patients completed the entire chemoradiotherapy regimen,during which no adverse reaction-related deaths *** terms of the recurrence pattern,17 patients had local recurrence,29 patients had distant metastasis,and 12 patients had peritoneal implantation *** 1-year,3-year,and 5-year overall survival(OS)rates were 83.7%,66.3%,and 60.0%,*** 1-year,3-year,and 5-year disease-free survival rates were 75.5%,62.7%,and 56.5%,*** analysis revealed that T stage,peripheral nerve invasion,and the lymph node metastasis rate(LNR)were independent prognostic factors for *** Postoperative intensi

关键词： Tumor recurrence Survival prognosis Advanced gastric cancer Radical resection Retrospective study

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基于表面层级结构的亲水微槽道减阻特性研究

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力学学报 2024年第6期56卷 1585-1594页

作者：朱明姚朝晖中国科学院大学工程科学学院北京100049

随着全球能源危机日益加剧,流动减阻研究引起众多学者注意.超疏水微槽道内表面的层级结构有助于形成气液界面,从而实现减阻,但亲水微槽道内表面层级结构的减阻特性尚不清楚.文章结合数值模拟和实验研究,对亲水微槽道内空间立柱结构(tran... 详细信息

随着全球能源危机日益加剧,流动减阻研究引起众多学者注意.超疏水微槽道内表面的层级结构有助于形成气液界面,从而实现减阻,但亲水微槽道内表面层级结构的减阻特性尚不清楚.文章结合数值模拟和实验研究,对亲水微槽道内空间立柱结构(transverse post structure,TPS)、二次内凹的空间立柱结构(doubly reentrant transverse post structure,DR-TPS)和二次内凹的微脊结构(doubly reentrant surface groove structure,DR-SGS),共3种表面层级结构的减阻特性进行了研究.研究发现,当气液界面稳定时,3种结构均有一定的减阻效果,其中,TPS和DR-TPS减阻效果相似,DR-SGS减阻效果最好,减阻率最高可达11.8%.经模拟发现,TPS和DR-TPS减阻效果低于DR-SGS的原因是它们的层级结构附近存在涡结构,造成了局部增阻.此外,流速对于3种结构的减阻效果也有影响,当流速较大时,结构中的气液界面容易失稳,从而使减阻效果减弱甚至出现增阻现象,TPS,DR-TPS和DR-SGS 3种结构维持气液界面稳定的能力依次增强.

关键词：微槽道格子玻尔兹曼方法层级结构气液界面减阻特性

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