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Ultrahard X-ray multifunctional application beamline at the SSRF

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Nuclear Science and Techniques 2024年第6期35卷 14-25页

作者： Ke Yang Zhao-Hui dong Chun-Yin Zhou Zi-Long Zhao dong-Xu Liang Sai-Chao Cao Ai-Guo Li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation *** primary X-ray techniques used at the beamline are high-energy X-ray diffraction and imaging using white and monochromatic *** main scientific objectives of ultrahard X-ray beamlines are focused on two research *** is the study of the structural properties of Earth’s interior and new materials under extreme high-temperature and high-pressure conditions,and the other is the characterization of materials and processes in near-real service *** beamline utilizes a superconducting wiggler as the light source,with two diamond windows and SiC discs to filter out low-energy light(primarily below 30 keV)and a Cu filter assembly to control the thermal load entering the subsequent optical *** beamline is equipped with dual *** first was a meridional bending Laue monochromator cooled by liquid nitrogen,achieving a full-energy coverage of 30-162 *** second was a sagittal bending Laue monochromator installed in an external building,providing a focused beam in the horizontal direction with an energy range of 60-120 *** were four experimental hutches:two large-volume press experimental hutches(LVP1 and LVP2)and two engineering material experimental hutches(ENG1 and ENG2).Each hutch was equipped with various near-real service conditions to satisfy different *** example,LVP1 and LVP2 were equipped with a 200-ton DDIA press and a 2000-ton dual-mode(DDIA and Kawai)press,***1 and ENG2 provide in situ tensile,creep,and fatigue tests as well as high-temperature *** June 2023,the BL12SW has been in trial *** is expected to officially open to users by early 2024.

关键词： Shanghai Synchrotron Radiation Facility Ultrahard X-ray High energy diffraction High energy imaging Engineering materials Earth science

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo Cheng Peng Zeng Chuan-Zhi Zang Qing-Wei dong Guang-Xi Wan Xiao-Ting dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

On the Responsible Use of Chatbots in Bioinformatics

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 1-3页

作者： Gangqing Hu Li Liu dong Xu Department of Microbiology Immunology&Cell BiologyWest Virginia UniversityMorgantownWV 26506USA College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Biodesign Institute Arizona State UniversityTempeAZ 85281USA Department of Electrical Engineer and Computer Science Christopher S.Bond Life Sciences CenterUniversity of MissouriColumbiaMO 65211USA

Large language model(LLM)-based chatbots like Chat Generative Pre-trained Transformer(ChatGPT),equipped with broad biological knowledge[1],have demonstrated an impressive capability for bioinformatics coding[2].When given well-crafted instructions,these chatbots hold the potential to significantly augment bioinformatics education and research[3,4].However,opportunities entail both rewards and *** commentary explores the challenges of using chatbots in bioinformatics and proposes strategies to manage the associated risks while maximizing the benefits.

关键词： equipped while education

Miniaturized, Wide Stopband Filter Based on Shielded Capacitively Loaded SIW Resonators

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Chinese Journal of Electronics 2024年第2期33卷 456-462页

作者： Yan ZHENG Hanyu TIAN Yuandan dong University of Electronic Science and Technology of China (UESTC)

Based on the full-mode capacitively loaded substrate integrated waveguide（SIW） resonator and the miniaturized shielded half-mode capacitively loaded SIW（S-HMCSIW） cavities, a novel compact high-performance filter is proposed. The footprint of the half-mode SIW（HMSIW） is further reduced due to the application of the capacitive-loading technique. By applying cross coupling, the proposed SIW filter's transmission zero enhances the stopband rejection and shows excellent selectivity. For the bandpass filter, the measured |S21| and |S11| are better than 1.09 d B and-14 d B, respectively. And a 3-d B fractional bandwidth（FBW） of 9.14–10.76 GHz（FBW=16.2%）is also observed. The filter achieves a wide stopband with a-20 d B out-of-band rejection up to 2.69f0（f0= 10 GHz）,with a size of 0.39λg× 0.51λgonly. Good agreement between measurement and simulation is obtained.

关键词： Band-pass filters Wireless communication Couplings Resonator filters Microwave theory and techniques Filtering theory Passband

Combining TDLAS and multi-fusion algorithms for methane gas concentration detection

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Optoelectronics Letters 2024年第6期20卷 353-359页

作者： SHI Guojun SONG Xinmin dong Taiji School of Information&Electrical Engineering Heilongjiang Bayi Agricultural UniversityDaqing 163319China College of Electrical and Information Engineering Northeast Petroleum UniversityDaqing 163318China

High-precision methane gas detection is of great importance in industrial safety, energy production and environmental protection, etc. However, in the existing measurement techniques, the methane gas concentration information is susceptible to noise, which leads to its useful signal being drowned by noise. A fusion algorithm of variational modal decomposition(VMD) and improved wavelet threshold filtering is proposed, which is used in combination with tunable diode laser absorption spectroscopy(TDLAS) to implement a non-contact, high-resolution methane gas concentration detection. The fusion algorithm can perform noise reduction and further segmentation of the methane gas detection signal. And the simulation and experiment verify the effectiveness of the fusion algorithm, and the experimental results show that for the detection of air containing 10 ppm, 30 ppm, 60 ppm, 80 ppm, and 99 ppm methane, the errors are 12.75%, 8.18%, 3.37%, 2.46%, and 1.78%, respectively.

关键词： Combining TDLAS and multi-fusion algorithms for methane gas concentration detection TDLAS

ZP2:the precision regulator of egg coat architecture during fertilization

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Science China(Life Sciences) 2024年第8期67卷 1779-1780页

作者： Yi dong Shigang Zhao Han Zhao State Key Laboratory of Reproductive Medicine and Offspring Health Center for Reproductive MedicineInstitute of WomenChildren and Reproductive HealthShandong UniversityJinan 250012China

In a recent study published in Cell,(Nishio et al.,2024)elucidated the molecular regulatory mechanism through which organisms prevent *** process intricately involves conformational changes in the zona pellucida(ZP)*** authors present a fascinating mechanism whereby post-fertilization cleavage of the ZP subunit ZP2 triggers its oligomerization,leading to crosslinking of filaments to harden the egg coat and prevent *** also systematically analyzed the pattern of ZP filament assembly,which revealed that two protofilaments comprising type I(ZP3)and type II(ZP1/ZP2/ZP4)components interlock to form a left-handed double helix *** findings are immensely beneficial for understanding the specific role of the egg coat,providing a plethora of insights.

关键词： mechanism finding crosslinking

Synergistic Brønsted Base/Photoredox-Catalyzed Three-Component Coupling with Malonates to Synthesize δ-Hydroxy Esters and δ-Keto Esters

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Chinese Journal of Chemistry 2024年第9期42卷 957-962页

作者： Ting Li Wei Wang Ming dong Zhije Zhang Sha Yu Zhengchu Chen Siping Wei dong Yi Green Pharmaceutical Technology Key Laboratory of Luzhou City Central Nervous System Drug Key Laboratory of Sichuan ProvinceSchoolof PharmacySouthwestMedicalUniversityLuzhouSichuan 646000China Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province LuzhouSichuan 646000China

Multicomponent alkene 1,2-dicarbofunctionalizations(DCFs)have emerged as a powerful strategy to rapidly incorporate both two carbon subunits across one C-C double bond in one step for enhancing molecular complexity and *** the best of our knowledge,there is only one report on photoredox-catalyzed three-component DCFs with malonates through the radical−radical cross-coupling,while photoredox-catalyzed radical-polar crossover(RPC)-type DCFs with malonates were still ***,we describe a redox-neutral RPC-type 1,2-dialkylation of styrenes with malonates and aldehydes through the synergistic Brønsted base/photoredox catalysis *** transition-metal-free strategy provides an efficient and clean approach to a broad variety ofδ-hydroxy esters and also features exceptionally mild conditions,wide compatibility of substrate scope and functional groups,and high atomic ***,three-component 1,2-alkylacylation from the same starting materials was achieved in one-pot manner through such RPC-type coupling and subsequent two-electron oxidation process,providing a set ofδ-keto esters of interest in pharmaceutical research.

关键词： Alkene difunctionalization Photoredox catalysis Malonates Radical reactions C-C coupling Synthetic methods Aldehydes Alkylation Multicomponentreactions

Landsat Image-Based Spatiotemporal Variation Analysis of Erosion and Deposition off the Qingshuigou of the Yellow River Delta from 1984 to 2021

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Journal of Ocean University of China 2024年第5期23卷 1173-1184页

作者： dong Sheng LI Songda TAO Shanshan College of Engineering Ocean University of China

Owing to climate change and human activity, the Qingshuigou of the Yellow River Delta(YRD) has undergone dynamic changes in erosion and deposition. Therefore, studying these changes is important to ensure ecological protection and sustainable development. In this study, the trend of erosion-deposition evolution in the Qingshuigou was investigated based on 38 coastline phases extracted from Landsat series images of the YRD at one-year intervals from 1984 to 2021. The periodicity of the scouring and deposition evolution was also analyzed using wavelet analysis. Results showed that the total area of the Qingshuigou was affected by deposition and erosion and that the fluctuation first increased and then decreased. The total area reached a maximum in 1993. The depositional area first increased and then decreased, whereas the overall erosion area decreased. Deposition and erosion areas showed periodic changes to some extent; however, the periodic signal intensity decreased. Furthermore, factors including channel morphological evolution and variations in water and sediment discharge affect the spatiotemporal dynamics of erosion and deposition processes. The application of nonconsistency tests finally revealed that deposition area and flushing magnitude exhibited non-stationarities, which are potentially attributed to impacts from climatic change drivers.

关键词： coastline erosion and deposition remote sensing wavelet analysis Yellow River Delta

Simplified prediction models for acoustic installation effects of train-mounted equipment

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Railway Engineering Science 2024年第2期32卷 125-143页

作者： David Thompson dong Zhao Giacomo Squicciarini Institute of Sound and Vibration Research University of SouthamptonSouthampton SO171BJUK

Acoustic models of railway vehicles in standstill and pass-by conditions can be used as part of a virtual certification process for new *** each piece of auxiliary equipment,the sound power measured on a test bench is combined with meas-ured or predicted transfer *** is important,however,to allow for installation effects due to shielding by fairings or the train *** the current work,fast-running analytical models are developed to determine these installation *** model for roof-mounted sources takes account of diffraction at the corner of the train body or fairing,using a barrier *** equipment mounted under the train,the acoustic propagation from the sides of the source is based on free-field Green’s *** bottom surfaces are assumed to radiate initially into a cavity under the train,which is modelled with a simple diffuse field *** sound emitted from the gaps at the side of the cavity is then assumed to propagate to the receivers according to free-field Green’s *** show good agreement with a 2.5D boundary element model and with *** uncertainty and parametric uncertainty are *** largest variability occurs due to the height and impedance of the ground,especially for a low *** leads to standard deviations of up to 4 dB at low *** the roof-mounted sources,uncertainty over the location of the corner used in the equivalent barrier model can also lead to large standard deviations.

关键词： Train noise Auxiliary equipment Acoustic installation effects Virtual certification Uncertainty