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Simulation and reconstruction of particle trajectories in the CEPC drift chamber

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Nuclear Science and Techniques 2024年第8期35卷 9-22页

作者： Meng‑yao liu Wei‑Dong Li Xing‑Tao Huang yao Zhang Tao Lin Ye yuan Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China Institute of High Energy Physics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The circular electron-positron collider(CEPC)is designed to precisely measure the properties of the Higgs boson,study electroweak interactions at the Z-boson peak,and search for new physics beyond the Standard *** a component of the 4th conceptual CEPC detector,the drift chamber facilitates the measurement of charged *** study implemented a Geant4-based simulation and track reconstruction for the drift *** the simulation,detector construction and response were implemented and added to the CEPC simulation *** development of track reconstruction involves track finding using the combinatorial Kalman filter method and track fitting using the tool of *** the simulated data,the tracking performance was *** results showed that both the reconstruction resolution and tracking efficiency satisfied the requirements of the CEPC experiment.

关键词： CEPC Drift chamber Detector simulation Track reconstruction

Understanding the initial use stage of cement mortar lining in drinking water distribution systems:Silicon and aluminum as stability indicators

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Journal of Environmental Sciences 2024年第1期135卷 495-505页

作者： Qiaozhi liu yuan Zhuang Guiwei Li yao Zhang Marc A.Edwards Baoyou Shi Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Civil and Environmental Engineering Virginia TechBlacksburgVA 24061USA

The cement mortar lining(CML)of commonly used ductile iron pipes can severely deteriorate the drinking water quality at the initial stage of use,but the behavioral characteristics of different elements release from the CML in this stage is still *** this study,dynamic immersion experiments with new cement mortar lined ductile iron pipe reactors were conducted under different feed water hardness and alkalinity *** results showed that the release of alkaline substances from the CML at the initial stage of use could strongly influence the pH of water,which consequently greatly impacted the release/precipitation behaviors of calcium,aluminum and *** pH and aluminum concentration of the effluent water could reach 11.5 and 700μg/L within 24 hr of hydraulic retention time,respectively,under conditions of relatively lower hardness and *** to the pH elevation,calcium carbonate precipitation could occur even at much lower feed water *** the aluminum and silicon could keep release from the CML in soluble form at different hardness and alkalinity levels,and their release rate depended on the amount of calcium carbonate ***,aluminum and silicon were more suitable as indicators of the corrosion intensity at the initial stage of CML use rather than the traditional calcium carbonate precipitation *** feed water hardness and alkalinity levels for mitigating the initial intense corrosion of CML were proposed:hardness>40 mg/L(CaCO_(3)),alkalinity>100 mg/L(CaCO_(3)).

关键词： Cement mortar lining Hardness Alkalinity Elemental release Drinking water supply

Nickel-Catalyzed Regioselective Hydrosilylation of Conjugated Dienes

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Chinese Journal of Chemistry 2024年第1期42卷 13-19,I0004页

作者： Xiaoyu Wu Wei liu Liqun Yang Yue Wang Tianwen liu yao yuan Yan Lu Zhaoguo Zhang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs School of Chemistry and Chemical EngineeringShanghai JiaoTong University800 Dongchuan RoadShanghai 200240China Joseph Black Building The University of EdinburghDavid Brewster RoadEdinburghEH9 3FJUK

With the increasing demand for homoallylic silanes and allylic silanes,the highly efficient and regioselective hydrosilylations of conjugated dienes are urgently ***,we developed a Ni-catalyzed regiodivergent hydrosilylation of aromatic conjugated dienes by adjusting the temperature and *** low temperature(-30℃),an eternal-ligand-free system(Ni/t-BuOk)can efficiently facilitate the 3,4-anti-Markovnikov hydrosilylation to provide homoallylic silanes via electrophilic activation process;under room temperature(25℃),a ligand-controlled system(Ni/t-BuOk/PPh3)can eventuate the 3,4-Markovnikov hydrosilylation to produce allylic silanes via Chalk-Harrod *** systems are compatible with various conjugated dienes and primary silanes in excellent yields andregioselectivities.

关键词： Nickel-catalyzed Regioselective hydrosilylation Conjugated dienes Electrophilic activation Homoallylic silanes

Effect of aspect ratio of elliptical stirred vessel on mixing time and flow field characteristics in the absence of baffles

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Chinese Journal of Chemical Engineering 2024年第1期65卷 63-74页

作者： yuan yao Peiqiao liu Qian Zhang Zequan Li Benjun Xi Changyuan Tao Yundong Wang Zuohua liu School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China Hubei Three Gorges Laboratory Yichang 443007China Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

Elliptical tanks were used as an alternative to circular tanks in order to improve mixing efficiency and reduce mixing time in unbaffled stirred tanks(USTs). Five different aspect ratios of elliptical vessels were designed to compare their mixing time and flow field. Computational fluid dynamics(CFD) simulations were performed using the k–ε model to calculate the mixing time and simulate turbulent flow field features, such as streamline shape, velocity distribution, vortex core region distribution, and turbulent kinetic energy(TKE) transfer. Visualization was also carried out to track the tinctorial evolution of the liquid phase. Results reveal that elliptical stirred tanks can significantly improve mixing performance in USTs. Specifically, the mixing time at an aspect ratio of 2.00 is only 45.3% of the one of a circular stirred tank. Furthermore, the secondary flow is strengthened and the vortex core region increases with the increase of aspect ratio. The axial velocity is more sensitive to the aspect ratio than the circumferential and radial velocity. Additionally, the TKE transfer in elliptical vessels is altered. These findings suggest that elliptical vessels offer a promising alternative to circular vessels for enhancing mixing performance in USTs.

关键词： Mixing time CFD Stirred tank Secondary flow Mixing performance

Numerical investigation of non-uniform temperature fields for proppant and fluid phases in supercritical CO_(2)fracturing

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Particuology 2024年第7期90卷 149-163页

作者： Boyu liu Jun yao Research Center of Multiphase Flow in Porous Media China University of Petroleum(East China)Qingdao 266000China

The non-uniform temperature distribution in supercritical CO_(2)(Sc-CO_(2))fracturing influences the density,viscosity,and volume expansion or shrinkage rate of Sc-CO_(2),impacting proppant *** study presents a coupled computational fluid dynamics-discrete element method and heat transfer model to examine the effects of proppant bed shape and the heat transfers of proppant-wall,proppant-fluid,and fluid-wall on the fluid and proppant temperature *** Sc-CO_(2)volume expansion is assessed under various temperature conditions by evaluating the volume-averaged Sc-CO_(2)*** factors,including proppant size,shape,thermal conductivity,concentration,temperature difference,and injection velocity,are carefully analyzed to elucidate their *** findings elucidate the existence of four distinct zones in the fluid temperature *** zone exhibits different magnitudes of temperature change under diverse conditions and undergoes dynamic transformations with the development of the proppant *** fluid-wall heat transfer and the fluid temperatures in Zones C and D are significantly subject to the fluid injection velocity(governing the heating duration),the temperature difference between fluid and formation(impacting the magnitude of heat flux),and the proppant bed shape(controlling the effective heating area).Additionally,the proppant-wall and proppant-fluid heat transfers determine the temperatures of both the proppant bed and the fluid within Zone B,showing a strong correlation with proppant thermal conductivity,proppant size,injection velocity,and temperature *** proposed coupled model provides valuable insights into the temperature distributions and flow behaviors of temperature-dependent fracturing fluids and proppants.

关键词： CFD-DEM Heat transfer Compressible fluid CO_(2)sequestration Proppant transport

Higher ambient temperatures may worsen obstructive sleep apnea:A nationwide smartwatch-based analysis of 6.2 million person-days

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Science Bulletin 2024年第13期69卷 2114-2121页

作者： Anni Li Qingli Zhang yuan yao Xinlei Zhu Cong liu Yutao Guo Haidong Kan Renjie Chen School of Public Health Key Lab of Public Health Safety of the Ministry of Education and NHC Key Lab of Health Technology AssessmentFudan UniversityShanghai 200032China Ministry of Education-Shanghai Key Laboratory of Children’s Environmental Health Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Pulmonary Vessel and Thrombotic Disease Sixth Medical CenterChinese PLA General HospitalBeijing 100048China Institute for Hospital Management Research Chinese PLA General HospitalBeijing 100048China Children’s Hospital of Fudan University National Children’s Medical CenterShanghai 201102China School of Public Health Hengyang Medical SchoolUniversity of South ChinaHengyang 421001China

Obstructive sleep apnea(OSA)is a serious type of sleep disorder that can lead to cardiometabolic and neurocognitive *** utilized smart device-based photoplethysmography technology to collect sleep data from the Chinese population from 2019 to *** lag nonlinear models combined with a generalized nonlinear model or a linear mixed effects model were used to investigate the shortterm associations between daily temperature and indicators of OSA *** included a total of 6,232,056 d of sleep monitoring data from 51,842 participants with moderate to severe risk of OSA from 313 Chinese *** relationships between ambient temperature and OSA exacerbation,apneahypopnea index(AHI),and minimum oxygen saturation(MinSpO_(2))were almost linear and present only on the same *** temperatures were associated with a greater risk of OSA exacerbation,with an 8.4%(95%confidence interval(CI):7.6%–9.3%)increase per 10℃increase in temperature.A 10℃increase in daily temperature corresponded to an AHI increase of 0.70 events/h(95%CI:0.65–0.76)and a MinSpO_(2)decrease of 0.18%(95%CI:0.16%–0.19%).Exposure to elevated temperatures during the night can also lead to adverse *** effects of higher temperatures on OSA severity were stronger among men,participants with a body mass index24 kg/m2,those aged 45 years and older,individuals with a history of hypertension and diabetes,and during the cold *** large-scale,nationwide,longitudinal study provides robust evidence suggesting that higher ambient temperatures may immediately worsen OSA.

关键词： Obstructive sleep apnea Temperature Apnea-hypopnea index Oxygen saturation Smart device

Research on Credit Regulation Mechanism of E-commerce Platform Based on Evolutionary Game Theory

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 330-359页

作者： Zeguo Qiu Yuchen Yin yao yuan Yunhao Chen School of Computer and Information Engineering Harbin University of CommerceHarbin150028China School of Management Harbin University of CommerceHarbin150028China

In the growing e-commerce industry,the problem of malicious business operations has become increasingly prominent,exposing many problems such as weak supervision of e-commerce platforms and no way for consumers to *** order to solve the problems of counterfeit and shoddy products on e-commerce platforms and promote the sustainable development of the e-commerce industry in China,this paper constructs a three-party evolutionary game model of e-commerce platforms,merchants,and consumers,investigates the influence of each influencing factor on each party’s strategy choice,and provides targeted suggestions to e-commerce platforms based on relevant ***,the impact of several important parameters on the equilibrium solution is discussed through sensitivity *** results show that:1)the smaller the cost difference between active and negative regulation,the more the e-commerce platform tends to active regulation strategy,but increasing fines for dishonest merchants and consumer complaints have little impact on the e-commerce platform;2)increasing consumer compensation,creating an honest business environment,and reducing the cost of honest business all help companies tend to operate in good faith;3)the only factor that affects the tendency of consumer complaint strategies is the cost of *** loss suffered by silence and the compensation given to consumers have little effect on consumers’tendency to complain *** results can provide theoretical guidance for participants to make useful strategic decisions in the e-commerce market.

关键词： Evolutionary game e-commerce data simulation

Nonlinear robust adaptive control for bidirectional stabilization system of all-electric tank with unknown actuator backlash compensation and disturbance estimation

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Defence Technology（防务技术） 2024年第2期32卷 144-158页

作者： Shusen yuan Wenxiang Deng Jianyong yao Guolai Yang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

Since backlash nonlinearity is inevitably existing in actuators for bidirectional stabilization system of allelectric tank,it behaves more drastically in high maneuvering *** this work,the accurate tracking control for bidirectional stabilization system of moving all-electric tank with actuator backlash and unmodeled disturbance is *** utilizing the smooth adaptive backlash inverse model,a nonlinear robust adaptive feedback control scheme is *** unknown parameters and unmodelled disturbance are addressed separately through the derived parametric adaptive function and the continuous nonlinear robust *** the unknown backlash parameters are updated via adaptive function and the backlash effect can be suppressed successfully by inverse operation,which ensures the system ***,the system disturbance in the high maneuverable environment can be estimated with the constructed adaptive law online improving the engineering ***,Lyapunov-based analysis proves that the developed controller can ensure the tracking error asymptotically converges to zero even with unmodeled disturbance and unknown actuator *** co-simulations and experiments illustrate the advantages of the proposed approach.

关键词： Bidirectional stabilization system Robust control Adaptive control Backlash inverse Disturbance estimation

M^(6)A modification in cardiovascular disease:With a focus on programmed cell death

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Genes & Diseases 2024年第5期11卷 272-284页

作者： Wen Li yao liu Ruiyan Xu yuan Zong Lu He Jun Hu Guohua Li Institute of Cardiovascular Disease Key Laboratory for Arteriosclerology of Hunan ProvinceHunan International Scientific and Technological Cooperation Base of Arteriosclerotic DiseaseDepartment of PathophysiologyMOE Key Lab of Rare Pediatric DiseasesHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of Cardiovascular Medicine The Second Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of Obstetrics and Gynecology The First Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of Cardiovascular Surgery The Second Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China

N^(6)-methyladenosine(m^(6)A)methylation is one of the most predominant internal RNA modifications in eukaryotes and has become a hot spot in the field of epigenetics in recent *** diseases(CVDs)are a leading cause of death *** evidence demonstrates that RNA modifications,such as the m^(6)A modification,are associated with the development and progression of many diseases,including *** increasing body of studies has indicated that programmed cell death(PCD)plays a vital role in ***,the molecular mechanisms underlying m^(6)A modification and PCD in CVDs remain poorly ***,elaborating on the highly complex connections between the m^(6)A mechanisms and different PCD signaling pathways and clarifying the exact molecular mechanism of m^(6)A modification mediating PCD have significant meaning in developing new strategies for the prevention and therapy of *** is great potential for clinical application.

关键词： Apoptosis Autophagy Cardiovascular diseases Ferroptosis N^(6)-methyladenosine Programmed cell death Pyroptosis