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Optical Transient Source AT2021lfa:A Possible“Dirty Fireball”

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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

geochemical Characteristics and Hydrocarbon generation Modeling of the Paleocene Source Rocks in the Jiaojiang Sag,East China Sea Basin

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Journal of Earth Science 2024年第2期35卷 642-654页

作者： Chuang Lei Shiyan Yin Jiaren ye Jingfu Wu Zhaosheng Wang Bin gao Collaborative Innovation Center of green Development and Ecological Restoration of Mineral Resources North China University of Science and TechnologyTangshan063210China Key Laboratory of Tectonics and Petroleum Resources China University of GeosciencesMinistry of EducationWuhan430074China CNOOC Research Institute Ltd Beijing100028China

Jiaojiang sag in the East China Sea Basin is at the earlier exploration stage,where characterizing hydrocarbon generation of source rocks is important to understand oil-gas exploration *** geochemical and basin modeling analysis,hydrocarbon generation capacity and process of the Paleocene E_(1)y,E_(1)l and E_(1)m formations were *** show that E_(1)y and E_(1)l mudstones are high-quality source rocks with Type Ⅱ kerogen,which is dominated by both aquatic organisms and terrestrial higher plants deposited in sub-reduced environment.E_(1)m mudstone interbedded with thin carbonaceous mudstone and coal is poor-quality source rock with Type Ⅲ kerogen,whose organic matter was originated from terrestrial higher plants under oxidized *** by burial and maturity histories,E_(1)y and E_(1)l source rocks experienced two hydrocarbon generation stages,which took place in the Late Paleocene and in the Middle to Late Eocene,respectively,and had high hydrocarbon generation capacity with cumulative hydrocarbon volume of 363 and 328 mg/g,respectively.E_(1)m source rock only had one hydrocarbon generation process in the Late Eocene,which had low hydrocarbon generation capacity with cumulative hydrocarbon volume of only 24 mg/*** future oil-gas exploration in the Jiaojiang sag should focus on hydrocarbon generation center and select targets in the central uplift formed before the Miocene with high-quality traps.

关键词： East China Sea Basin Jiaojiang sag source rock geochemical characteristics hydrocarbon generation basin modeling petroleum geology

Multi-endpoint assays reveal more severe toxicity induced by chloraminated effluent organic matter than chloraminated natural organic matter

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Journal of Environmental Sciences 2024年第1期135卷 310-317页

作者： Hai-Yan Wang De-Xiu Wu ye Du Xiao-Tong Lv Qian-Yuan Wu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environmental Protection Key Laboratory of Microorganism Application and Risk Control Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental SafetyTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China College of Architecture and Environment Sichuan UniversityChengdu 610000China

Disinfection by chloramination produces toxic byproducts and the difference in toxicity of reclaimed and drinking water treated by chloramination remains *** study investigated cytotoxic effects at the same concentrations of dissolved organic matter and showed that chloraminated effluent organic matter(EfOM)induced 1.7 times higher cytotoxicity than chloraminated natural organic matter(NOM)applied to simulate drinking *** EfOM induced more reactive nitrogen species than chloraminated NOM,and chloraminated EfOM and NOM induced similar and higher levels of reactive oxygen species than the negative control,***,intracellular macromolecule damage indicated by DNA/RNA damage marker 8–hydroxy-(deoxy)guanosine and the intracellular protein carbonyl concentration induced by chloraminated EfOM was higher and slightly more than that induced by chloraminated NOM,*** data were consistent with the effects on cell physiological *** cycle arrest mainly occurred in g2 phase by chloraminated EfOM and *** apoptotic cells,which could return to normal,increased upon exposure to high concentrations of chloraminated EfOM and ***,necrotic cells were significantly increased from 0.5%to 2.5%when the concentration increased from 20-to 60-fold chloraminated EfOM,but were not obviously changed by chloraminated *** results indicated that the comprehensive intracellular changes induced by toxic substances in chloraminated EfOM were more irreversible and induced more cell death than chloraminated NOM.

关键词： Cytotoxicity Intracellular active nitrogen/oxygen Intracellular oxidative damage Cell necrosis Reclaimed water

Encouraging Solution to the Problem of Synthesizing Protein α-Thioester

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Chinese Journal of Chemistry 2024年第10期42卷 1114-1120页

作者： Xinliang Liu Zijun gao Jie Zhao Farong ye Ping Huang Ping Wang Center for Chemical glycobiology Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsFrontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringZhangjiang Institute for Advanced StudyShanghai JiaoTongUniversityShanghai 200240China Shenzhen Research Institute of Shanghai Jiao Tong University ShenzhenGuangdong 518057China

Expressed protein ligation(EPL)provides a powerful tool to access large-size proteins with precise *** methods for constructing the critical protein thioester for EPL have predominantly relied on the recombinant intein fusion expressed in Escherichia coli(***).Despite its powerful applications,the expression of thioester derived from eukaryotic protein in *** inherently suffers from its limited solubility,the inactivity of intein,premature hydrolysis and low *** overcome these obstacles,we present herein the facile one-flask synthesis of inaccessible proteinα-thioester via a SUMO-protein-intein(SPI)sandwich *** utility of SUMO enhances the protein fusion yield and solubility,prevents premature hydrolysis and simplifies the purification *** inaccessible protein thioester with internal Cys residues can be readily produced and is compatible with the EPL-desulfurization protocol used to prepare complex proteins,which is otherwise difficult to obtain using traditional *** utility has been highlighted through the synthesis of human granulocyte colony-stimulating factor(g-CSF).

关键词： Desulfurization glycoproteins glycopeptides Protein expression Peptide thioester

Multi-level temporal feature fusion with feature exchange strategy for multiple object tracking

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Optoelectronics Letters 2024年第8期20卷 505-512页

作者： gE Yisu ye Wenjie ZHang guodao LIN Mengying College of Computer Science and Artificial Intelligence Wenzhou University School of Computer Science and Technology Zhejiang Normal University Department of Digital Media Technology Hangzhou Dianzi University College of Intelligent Manufacturing Wenzhou Polytechnic

With the deepening of neural network research, object detection has been developed rapidly in recent years, and video object detection methods have gradually attracted the attention of scholars, especially frameworks including multiple object tracking and detection. Most current works prefer to build the paradigm for multiple object tracking and detection by multi-task learning. Different with others, a multi-level temporal feature fusion structure is proposed in this paper to improve the performance of framework by utilizing the constraint of video temporal consistency. For training the temporal network end-to-end, a feature exchange training strategy is put forward for training the temporal feature fusion structure efficiently. The proposed method is tested on several acknowledged benchmarks, and encouraging results are obtained compared with the famous joint detection and tracking framework. The ablation experiment answers the problem of a good position for temporal feature fusion.

关键词： A

OSDA-free synthesis of FeZSM-22 zeolite from natural minerals for n-octane hydroisomerization

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Chinese Journal of Chemical Engineering 2024年第2期66卷 51-59页

作者： Tiesen Li Ting Chen Yinghui ye Peng Dong TinghaiWang Qingyan Cui Chan Wang Yuanyuan Yue National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350002China Qingyuan Innovation Laboratory Quanzhou 362801China

A seed-directed approach to synthesizing Fe ZSM-22 zeolite without organic structure directing agent(OSDA)was developed by using Fe-rich diatomite as all aluminum and iron *** Fe ZSM-22zeolite with optimal crystallinity and purity can be obtained by systematically adjusting feed composition and synthesis *** show that Fe ZSM-22 zeolite synthesized with OSDA-free owns high crystallinity,obvious thin needle-shaped morphology and high Bronsted/Lewis acid ***,when used for n-octane hydroisomerization reaction,its derived catalyst exhibits the best catalytic performance reflected by the highest selectivity to C_(8)isomers compared to the two reference catalysts prepared based on a Fe-containing and a Fe-free ZSM-22 synthesized through an OSDA-directed route from natural diatomite and conventional chemicals,*** work provides an alternative route to sustainably synthesizing heteroatomic zeolites with high performance.

关键词： FeZSM-22 zeolite OSDA-free synthesis Natural minerals n-octane hydroisomerization

Through-polymer,via technology-enabled,flexible,lightweight,and integrated devices for implantable neural probes

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Microsystems & Nanoengineering 2024年第2期10卷 279-291页

作者： Cunkai Zhou ye Tian gen Li Yifei ye Lusha gao Jiazhi Li Ziwei Liu Haoyang Su Yunxiao Lu Meng Li Zhitao Zhou Xiaoling Wei Lunming Qin Tiger H.Tao Liuyang Sun College of Electronics and Information Engineering Shanghai University of Electric PowerShanghaiChina 2020 X-Lab Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghaiChina School of graduate Study University of Chinese Academy of SciencesBeijingChina State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghaiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina School of Physical Science and Technology ShanghaiTech UniversityShanghaiChina Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of SciencesShanghaiChina Neuroxess Co. Ltd.(Jiangxi)NanchangJiangxiChina guangdong Institute of Intelligence Science and Technology HengqinZhuhaiGuangdongChina Tianqiao and Chrissy Chen Institute for Translational Research ShanghaiChina

In implantable electrophysiological recording systems,the headstage typically comprises neural probes that interface with brain tissue and integrated circuit chips for signal *** advancements in MEMS and CMOS technology have significantly improved these components,their interconnection still relies on conventional printed circuit boards and sophisticated *** conventional approach adds considerable weight and volume to the package,especially for high channel count *** address this issue,we developed a through-polymer via(TPV)method inspired by the through-silicon via(TSV)technique in advanced three-dimensional *** innovation enables the vertical integration of flexible probes,amplifier chips,and PCBs,realizing a flexible,lightweight,and integrated device(FLID).The total weight of the FLIDis only 25%that of its conventional counterparts relying on adapters,which significantly increased the activity levels of animals wearing the FLIDs to nearly match the levels of control animals without ***,by incorporating a platinum-iridium alloy as the top layer material for electrical contact,the FLID realizes exceptional electrical performance,enabling in vivo measurements of both local field potentials and individual neuron action *** findings showcase the potential of FLIDs in scaling up implantable neural recording systems and mark a significant advancement in the field of neurotechnology.

关键词： alloy neural recording

A gel polymer electrolyte based on IL@NH_(2)-MIL-53(Al)for high-performance all-solid-state lithium metal batteries

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Chinese Journal of Chemical Engineering 2024年第5期69卷 47-55页

作者： Sijia Wang ye Liu Liang He Yu Sun Qing Huang Shoudong Xu Xiangyun Qiu Tao Wei School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037China College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China Power&Energy Storage System Research Center College of Mechanical and Electrical EngineeringQingdao UniversityQingdao 266071China

Solid polymer composite electrolytes possess the benefits of superior compatibility with electrodes and good thermal characteristics for more secure energy storage ***,a new gel polymer electrolyte(gPE)containing NH_(2)-MIL-53(Al),[PP_(13)][TFSI],LiTFSI,and PVDF-HFP was prepared using a simple method of solution *** effects of encapsulating different ratios of ionic liquid([PP_(13)][TFSI])into the micropores of functionalized metal-organic frameworks(NH_(2)-MIL-53(Al))on the electrochemical properties were ***,SEM,nitrogen adsorption-desorption isotherms,and electrochemical measurements were *** gPE demonstrates a superior ionic conductivity of 8.08×10^(-4)S·cm^(-1)at 60℃and can sustain a discharge specific capacity of 156.6 mA·h·g^(-1)at 0.2 C for over 100 *** work might offer a potential approach to alleviate the solid-solid contact with the solid-state electrolyte and electrodes and broaden a new window for the creation of all-solid-state batteries.

关键词： Metal-organic frameworks(MOFs) All solid-state lithium batteries(ASSLBs) Ionic liquid NH_(2)-MIL-53(Al) Solid-state electrolytes(SSEs)

Synthesis and microwave absorption performance of heat-treated RF/SiO_(2)aerogels

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Defence Technology（防务技术） 2024年第4期34卷 177-186页

作者： Xinli ye Hao Yu Kai Zheng Shan Li Xiaomin Ma Bangxiao Mao Junxiong Zhang School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072PR China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057PR China Yangtze River Delta Research Institute of Northwestern Polytechnical University Suzhou 215400PR China National Equipment New Material&Technology(Jiangsu)Co. LtdSuzhou 215400PR China Beijing Xinfeng Aerospace Equipment Co. LtdBeijing 100854PR China School of Textile and Clothing Nantong UniversityNantong 226019PR China

The well-designed composite with satisfactory electromagnetic microwave absorption at high temperatures remains a serious ***,we fabricated a resorcinol-formaldehyde/silica dioxide composite aerogel(RF/SiO_(2))with a three-dimensional network structure using sol-gel,atmospheric pressure drying technique as well as heat-treated processes to achieve enhanced microwave absorption capabilities in the low frequency *** pristine RF/SiO_(2)aerogel presented a typical micropores structure with a surface area,porous volume,and density of 146.82 m^(2)/g,62.40%,and 0.28 cm^(3)/g,***,the RF/SiO_(2)aerogel showed an effective absorption bandwidth of 3.56 gHz and a minimum reflection loss value of-46.10 d B at 2.25 mm after being heat-treated at 1500°C,while the maximum effective absorption bandwidth was 3.60 gHz at 2.30 *** intricate three-dimensional networks possessed remarkable impedance matching,multiple attenuation mechanisms,interfacial polarization,and dielectric loss,which were attributed to the exceptional ability to absorb electromagnetic *** offered a fresh approach to creating adaptable and effective microwave absorption materials in military defense.

关键词： RF/SiO_(2) Aerogel Heat-treated Microwave absorption