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Ultrasound sensing with optical microcavities

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Light(Science & Applications) 2024年第8期13卷 1487-1511页

作者： Xuening Cao Hao Yang Zu-Lei Wu bei-bei Li beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China Songshan Lake Materials Laboratory Dongguan 523808 GuangdongChina

Ultrasound sensors play an important role in biomedical imaging,industrial nondestructive inspection,*** ultrasound sensors that use piezoelectric transducers face limitations in sensitivity and spatial resolution when miniaturized,with typical sizes at the millimeter to centimeter *** overcome these challenges,optical ultrasound sensors have emerged as a promising alternative,offering both high sensitivity and spatial *** particular,ultrasound sensors utilizing high-quality factor(Q)optical microcavities have achieved unprecedented performance in terms of sensitivity and bandwidth,while also enabling mass production on silicon *** this review,we focus on recent advances in ultrasound sensing applications using three types of optical microcavities:Fabry-Perot cavities,π-phase-shifted Bragg gratings,and whispering gallery mode *** provide an overview of the ultrasound sensing mechanisms employed by these microcavities and discuss the key parameters for optimizing ultrasound ***,we survey recent advances in ultrasound sensing using these microcavity-based approaches,highlighting their applications in diverse detection scenarios,such as photoacoustic imaging,ranging,and particle *** goal of this review is to provide a comprehensive understanding of the latest advances in ultrasound sensing with optical microcavities and their potential for future development in high-performance ultrasound imaging and sensing technologies.

关键词： optical millimeter offering

The Essential 2-rank for Classical Groups

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2169-2186页

作者： Jian bei AN Yong XU Department of Mathematics University of AucklandAucklandNew Zealand School of Mathematics and Statistics He’nan University of Science and TechnologyLuoyang 471023P.R.China

Let G be a symplectic or orthogonal group defined over a finite field with odd characteristic and let D≤G be a Sylow *** this paper,we classify the essential 2-subgroups and determine the essential 2-rank of the Frobenius category FD(G).Together with the results of An–Dietrich and Cao–An–Zeng,this completes the work of essential subgroups and essential ranks of classical groups.

关键词： Frobenius category conjugation families essential 2-rank symplectic groups orthogonal groups

BLS-identification:A device fingerprint classification mechanism based on broad learning for Internet of Things

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Digital Communications and Networks 2024年第3期10卷 728-739页

作者： Yu Zhang bei Gong Qian Wang Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Information Science and Technology Zhengzhou Normal UniversityHenan450044China

The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security *** a network-level security authentication method,device fingerprint based on machine learning has attracted considerable attention because it can detect vulnerable devices in complex and heterogeneous access ***,flexible and diversified IoT devices with limited resources increase dif-ficulty of the device fingerprint authentication method executed in IoT,because it needs to retrain the model network to deal with incremental features or *** address this problem,a device fingerprinting mechanism based on a Broad Learning System(BLS)is proposed in this *** mechanism firstly characterizes IoT devices by traffic analysis based on the identifiable differences of the traffic data of IoT devices,and extracts feature parameters of the traffic packets.A hierarchical hybrid sampling method is designed at the preprocessing phase to improve the imbalanced data distribution and reconstruct the fingerprint *** complexity of the dataset is reduced using Principal Component Analysis(PCA)and the device type is identified by training weights using *** experimental results show that the proposed method can achieve state-of-the-art accuracy and spend less training time than other existing methods.

关键词： Device fingerprint Traffic analysis Class imbalance Broad learning system Access authentication

Recent progress in carbene-catalyzed fluoroalkylation

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Science China Chemistry 2024年第8期67卷 2448-2460页

作者： bei Zhang Xuan Zhang Jian Wang Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China

The fluoroalkyl fragment plays a vital role in various fields such as pharmaceuticals and materials science, and has a significant impact on human life not only on the present but also in the future. The insertion of fluoroalkyl groups into the chemical skeletons can cause considerable alternations in the chemical, physical and biological properties of molecules, which has attracted numerous scientists from different fields. This review focuses on N-heterocyclic carbene(NHC)-catalyzed fluoroalkylation reactions, providing a detailed analysis and summary of the achievements in the past two decades. Many successful examples clearly indicate that NHCs can catalyze the tranformation of fluoroalkylation reagents with various electronic characteristics, whether electrophilic, nucleophilic, or radical precursors. Herein, the fluoroalkylation reactions are classified based on different catalytic modes of NHCs: Lewis base catalysis, Umploung catalysis, radical catalysis and others. Meanwhile, by refining and systematically studying the contribution of NHC catalysis in fluoroalkylation reactions, this review is expected to provide valuable insights and enlightenment for related fields.

关键词： N-heterocyclic carbene fluoroalkylation radical catalysis

Function-reversible facets enabling SrTiO_(3)nanocrystals for improved photocatalytic hydrogen evolution

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Frontiers in Energy 2024年第1期18卷 101-109页

作者： Bin WANG bei AN Xiaoqian LI Shaohua SHEN School of Physics Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter(Ministry of Education)Key Laboratory of Shaanxi for Advanced Materials and Mesoscopic PhysicsXi’an Jiaotong UniversityXi’an 710049China International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an 710049China

It has been widely reported that,for faceted nanocrystals,the two adjacent facets with different band levels contribute to promoted charge separation,and provide active sites for photocatalytic reduction and oxidation reaction,*** such cases,only one family of facets can be used for photocatalytic hydrogen ***,by using SrTiO_(3)nanocrystals enclosed by{023}and{001}facets as a model photocatalyst,this paper proposed a strategy to achieve the full-facets-utilization of the nanocrystals for photocatalytic hydrogen via chemically depositing Pt nanoparticles on all *** photo-deposition experiment of CdS provided direct evidence to demonstrate that the{023}facets which were responsible for photooxidation reaction can be function-reversed for photocatalytic hydrogen evolution after depositing Pt nanoparticles,together with the{001}***,the full-facets-utilization led to a much-improved activity for photocatalytic hydrogen,in contrast to those SrTiO_(3)nanocrystals with only{001}facets deposited by Pt nanoparticles via a photo-deposition method.

关键词： SrTiO_(3)nanocrystals crystal facets photocatalysis hydrogen evolution

Risk Factors Asscociated with Hypokalemia during Postanesthesia Recovery and Its Impact on Outcomes in Gynecological Patients:A Propensity Score Matching Study

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Current Medical Science 2024年第2期44卷 441-449页

作者： bei-bei WANG Li HU Xin-yue HU Dong HAN Jing WU Department of Anesthesiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China Institute of Anesthesia and Critical Care Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China Key Laboratory of Anesthesiology and Resuscitation(Huazhong University of Science and Technology) Ministry of EducationWuhan430022China

Objective:This study aimed to explore the risk factors and outcomes of hypokalemia during the recovery period from anesthesia in the gynecological ***:This retrospective cohort study included 208 patients who underwent gynecological surgery at our institution between January 2021 and March *** were collected for each patient,including demographics,disease status,surgical data,and clinical *** bowel preparation,postoperative gastrointestinal function,and electrolyte levels were compared between the two groups using propensity score matching(PSM).Results:The incidence of hypokalemia(serum potassium level<3.5 mmol/L)during the recovery period from anesthesia was approximately 43.75%.After PSM,oral laxative use(96.4%vs.82.4%,P=0.005),the number of general enemas(P=0.014),and the rate of≥2 general enemas(92.9%vs.77.8%,P=0.004)were identified as risk factors for hypokalemia,which was accompanied by decreased PaCO_(2) and *** were no significant differences in postoperative gastrointestinal outcomes,such as the time to first flatus or feces,the I-FEED score(a scoring system was created to evaluate impaired postoperative gastrointestinal function),or postoperative recovery outcomes,between the hypokalemia group and the normal serum potassium ***:Hypokalemia during postanesthesia recovery period occurred in 43.75%of gynecological patients,which resulted from preoperative mechanical bowel preparation;however,it did not directly affect clinical outcomes,including postoperative gastrointestinal function,postoperative complications,and length of hospital stay.

关键词： hypokalemia gynecological surgery postanesthesia recovery perioperative electrolyte disturbances postoperative recovery

Coupling ideality of standing-wave supermode microresonators

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Photonics Research 2024年第8期12卷 1610-1618页

作者： MIN WANG YUECHEN LEI ZHI-GANG HU CHENGHAO LAO YUANLEI WANG XIN ZHOU JINCHENG LI QI-FAN YANG bei-bei LI beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China School of Physics Beihang UniversityBeijing 100191China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Songshan Lake Materials Laboratory Dongguan 523808China

Standing-wave supermode microresonators that are created through the strong coupling between counter-propagating modes have emerged as versatile platforms for sensing and nonlinear *** example,these microresonators have shown potential in nanoparticle sizing and counting,as well as enhancing the single-photon optomechanical coupling rate of stimulated Brillouin ***,it has been observed that the relation between the mode linewidth and on-resonance transmission of the split supermodes differs obviously from that of the non-split *** behavior is typically quantified by the coupling ideality(I),which remains inadequately explored for the standing-wave *** this study,we theoretically and experimentally investigate the coupling ideality of standing-wave supermodes in a commonly employed configuration involving a Si O2microresonator side-coupled to a tapered *** findings demonstrate that,even with a single-mode tapered fiber,the coupling ideality of the standing-wave supermodes is limited to 0.5,due to the strong backscattering-induced energy loss into the counter-propagating direction,resulting in an additional equivalent parasitic *** achieving a coupling ideality of 0.5 presents challenges for reaching over-coupled regimes,it offers a convenient approach for adjusting the total linewidth of the modes while maintaining critically-coupled conditions.

关键词： ideality mode wave

Optimizing extractants selection for efficient separation of phenols and nitrogen-containing heteroaromatics using hydrogen bond interaction strategies

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Chinese Journal of Chemical Engineering 2024年第4期68卷 43-52页

作者： Pengzhi bei Rui Zhang Jie Feng Antony Rajendran Wenying Li State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024China Department of Chemistry Mepco Schlenk Engineering College(Autonomous)Sivakasi 626005India

Focusing on the use of imidazolium ionic liquids and quaternary ammonium salts-based deep eutectic solvents for the separation of phenols and nitrogen-containing heteroaromatics,the role of heteroaromatics as specific sites for hydrogen bond-based separation has been *** environmentally friendly solvents are known for their ability to form hydrogen bonds with heteroatoms,a key aspect in separation *** quantified the hydrogen bond interaction energy to reach the threshold energy for efficient O-and N-heteroaromatics *** article provides an in-depth study of the structural nuances of different hydrogen bonding sites and their affinity properties while conducting a comparative evaluation of the separation efficiency of ionic liquids and deep eutectic solvents from a thermodynamic *** showed that phenols with dual hydrogen bonding recognition sites were easier to separate than nitrogen-containing *** ionic liquids were more suitable for the extraction of nonbasic nitrogen-containing heteroaromatics,and quaternary ammonium salts-based deep eutectic solvents are more effective for phenols and basic nitrogen-containing heteroaromatics,which was confirmed by Fourier transform infrared spectroscopy and empirical ***,this study provides a theoretical basis for the strategy design and selection of extractants for the efficient separation of O-and N-containing aromatic compounds.

关键词： Deep eutectic solvents Hydrogen bond Ionic liquids Separation Solvents Structural characteristics

Using deep neural networks coupled with principal component analysis for ore production forecasting at open-pit mines

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 727-740页

作者： Chengkai Fan Na Zhang bei Jiang Wei Victor Liu Department of Civil and Environmental Engineering University of AlbertaEdmontonAlbertaT6G 2E3Canada Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada

Ore production is usually affected by multiple influencing inputs at open-pit ***,the complex nonlinear relationships between these inputs and ore production remain *** becomes even more challenging when training data(*** haulage information and weather conditions)are *** machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden *** study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training *** the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input *** verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark *** DNN model with multiple hidden layers performed better than the ANN models with a single hidden *** DNN model outperformed the extensively applied benchmark models in predicting ore *** can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines.

关键词： Oil sands production Open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering