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Nitrogen isotope stratigraphy of the Early Cambrian successions in the Tarim Basin:Spatial variability of nitrogen cycling and its implication for paleo-oceanic redox conditions

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Acta Geochimica 2024年第4期43卷 785-801页

作者： Bi zhu Xuefeng Li Lu Ge Yongquan chen Institute of Earth’s Critical Zone School of Earth Sciences and EngineeringHohai UniversityNanjing 210098China Research Institute of Exploration and Development Tarim Oil Field CompanyPetroChinaKorlaChina

The Early Cambrian represents a critical time period characterized by extraordinary biological innovations and dynamic redox conditions in *** isotopic signatures of ancient sediments have the potential to elucidate the evolutionary path of marine redox states and the biogeochemical nitrogen cycle within the water column of the Early Cambrian *** existing research on this topic has predominantly focused on South China,the exploration of other continental margins has been limited,leaving contradictory hypotheses *** this study,pairedδ^(15)N andδ^(13)C org analyses were performed on the Lower Cambrian successions from the Shiairike section(inner ramp)and Well Tadong 2(deep shelf/basin)in the northwestern and eastern Tarim Basin,*** data from the Shiairike section reveal a discernible shift in the operation of different nitrogen cycles for the black chert-shale unit,also referred to as the black rock series in Chinese literature,of the yurtus Formation(Fortunian stage to lower Stage 3).Oscillatingδ^(15)N values for its lower part are suggestive of alternating anaerobic assimilation of NH 4+and denitrification/*** is likely attributed to a shallow,unstable chemocline consistent with the upwelling and incursion of deep,anoxic waters during a major *** contrast,aerobic nitrogen cycling,indicated by positiveδ^(15)N values of>2‰,dominated the upper part alongside a reduction in upwelling *** the other hand,theδ^(15)N signatures of Xishanbulake and Xidashan Formations of Well Tadong 2,which encompass a time interval from the Cambrian Fortunian Age to Age 4,are indicative of N_(2)fixation by diazotrophs as the major nitrogen *** two studied intervals,although not time-equivalent,exhibit separated states of nitrogen cycling at least during the deposition of the yurtus black rock *** spatially different nitrogen cycling of the studied sections is compatible with a redox-stratified ocean dur

关键词： Nitrogen isotopes Early Cambrian Tarim Black rock series

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Quantum Spin Exchange Interactions to Accelerate the Redox Kinetics in Li–S Batteries

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Nano-Micro Letters 2024年第5期16卷 370-383页

作者： yu Du Weijie chen yu Wang yue yu Kai Guo Gan Qu Jianan Zhang Key Laboratory of Advanced Energy Catalytic and Functional Materials Preparation of Zhengzhou City College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001People’s Republic of China

Spin-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–S *** selec-tion,spin-dependent electron mobility and spin potentials in activation barriers can be optimized as quantum spin exchange interactions lead-ing to a significant reduction of the electronic repulsions in the orbitals of ***,we anchor the MgPc molecules on fluorinated carbon nanotubes(MgPc@FCNT),which exhibits the single active Mg sites with axial *** to the density functional theory calculations,the electronic spin polarization in MgPc@FCNT not only increases the adsorption energy toward LiPSs intermediates but also facilitates the tunneling process of electron in Li–S *** a result,the MgPc@FCNT provides an initial capacity of 6.1 mAh cm^(-2) even when the high sulfur loading is 4.5 mg cm^(-2),and still maintains 5.1 mAh cm^(-2) after 100 *** work provides a new perspective to extend the main group single-atom catalysts enabling high-performance Li–S batteries.

关键词： Metal phthalocyanines Spin polarization Electrocatalysis Li–S batteries

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Recent progress of vaccines administration via microneedles for cancer immunotherapy

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Chinese Chemical Letters 2024年第3期35卷 96-103页

作者： yuanzheng chen Jiaojiao zhu Jinsong Ding Wenhu Zhou Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China Key Laboratory of Biological Nanotechnology of National Health Commission Changsha 410008China

Therapeutic cancer vaccines have undergone a resurgence in the past *** of the high level of immune cell accumulation and abundant capillary lymphatic system in the dermis,percutaneous vaccination is considered to be an ideal treatment *** convenient administration,the recent development of microneedles(MNs)provides a safe,painless,and low-cost transdermal delivery strategy,which could bypass the first-pass metabolism of vaccines for enhanced stability and ***,the therapeutic effect of MNs-based cancer vaccines is not optimal,which is limited by the complex set of host,tumor,and environmental factors,as well as the limited vaccine loading ***,further improvements are still required to push their clinical *** this critical review,we deliberate on how to improve the therapeutic effect of MNs-based vaccines for cancer immunotherapy,summarize the recent advances in MNs-based cancer vaccination,and provide an overview of various design strategies and mechanisms for active or passive targeting delivery,aiming to develop safer,more effective,and more stable MNs-based cancer ***,we briefly describe the potential of vaccine platforms in combination with other therapies,suggest the need to design vaccines according to specific circumstances,and discuss the biosafety of repeated administration for enhancing clinical efficacy.

关键词： Transdermal delivery Microneedles Cancer vaccine Immunotherapy Nanoparticle Lymph node

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Generalized Inverses and Units in a Unitary Ring

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1000-1014页

作者： yu Kun ZHOU Jian Long chen School of Mathematics Southeast UniversityNanjing 210096P.R.China

Let R be a unitary ring and a,b∈R with ab=*** find the 2/3 property of Drazin invertibility:if any two of a,b and a+b are Drazin invertible,then so is the third ***,we combine the 2/3 property of Drazin invertibility to characterize the existence of generalized inverses by means of *** applications,the need for two invertible morphisms used by You and chen to characterize the group invertibility of a sum of morphisms is reduced to that for one invertible morphism,and the existence and expression of the inverse along a product of two regular elements are obtained,which generalizes the main result of Mary and Patricio(2016)about the group inverse of a product.

关键词： Leftπ-regular element stronglyπ-regular element group inverse Drazin inverse inverse along an element

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BIM-based framework of automatic tunnel segment assembly and deviation control

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Underground Space 2024年第3期16卷 59-78页

作者： Jian Gong Tengfei Bao Zheng zhu Hong yu Yangtao Li The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China College of Hydraulic and Environmental Engineering China Three Gorges UniversityYichang 443002China Zhejiang Design Institute of Water Conservancy and Hydro-Electric Power Hangzhou 310002China

The design of universal segments and deviation control of segment assembly are essential for robust and low-risk tunnel construction.A building information modeling(BIM)-based framework was proposed for parametric modeling,automatic assembly,and deviation control of universal ***,segment models of different levels of detail(LoDs)were built based on BIM visual programming language(VPL)for different project life ***,the geometric constraints,requirements,and procedures for parametric segment assembly were distilled to develop a program that combines a novel typesetting algorithm with a 3D path replanning *** is implemented by introducing a point indication matrix,characterizing segments by sides,and manipulating geometries in a ***,3D path replanning,with non-uniform rational B-splines(NURBS)and arcs as basic shapes,was used to resolve unacceptable deviation situations after ***,the proposed framework was validated on a water diversion line and was found to be more effective and accurate than the previous method.

关键词： Parametric generative design BIM Deviation control Typesetting 3D path replanning

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The posterior selection method for hyperparameters in regularized least squares method

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Control Theory and Technology 2024年第2期22卷 184-194页

作者： Yanxin Zhang Jing chen Yawen Mao Quanmin zhu School of Science Jiangnan UniversityWuxi214122JiangsuChina The Science and Technology on Near-Surface Detection Laboratory Wuxi214122JiangsuChina Department of Engineering Design and Mathematics University of the West of EnglandBristolBS161QYUK

The selection of hyperparameters in regularized least squares plays an important role in large-scale system identification. The traditional methods for selecting hyperparameters are based on experience or marginal likelihood maximization method, which are inaccurate or computationally expensive. In this paper, two posterior methods are proposed to select hyperparameters based on different prior knowledge (constraints), which can obtain the optimal hyperparameters using the optimization theory. Moreover, we also give the theoretical optimal constraints, and verify its effectiveness. Numerical simulation shows that the hyperparameters and parameter vector estimate obtained by the proposed methods are the optimal ones.

关键词： Regularization method Hyperparameter System identification Least squares algorithm

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Effect of relative humidity on the desulfurization performance of calcium-based desulfurizer

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Journal of Environmental Sciences 2024年第4期138卷 179-188页

作者： Juan Lǖ yu Fu Haiyan yu HuanWang Zhe Wang Haiyan chen School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China Guangyuan Emergency Management bureau Guangyuan 628000China

Low desulfurization efficiency impedes the wide application of dry desulfurization technology,which is a low-cost and simple process,and one significant solution is the development and manufacture of high-performance *** this study,firstly,a steam jet mill was used to digest quicklime;then,we utilized numerical simulation to study the flow field distribution and analyze the driving factors of quicklime digestion;and lastly,the desulfurization performance of the desulfurizer was evaluated under different relative *** results show that the desulfurizer prepared via the steam jet mill had better apparent activity than traditional ***,the entire jet flow field of the steam jet mill is in a supersonic and highly turbulent flow state,with high crushing intensity and good particle acceleration *** contact with the nascent surface maximizes the formation of slaked *** experiments demonstrated that the operating time with 100%desulfurization efficiency and the“break-through”time for the desulfurizer prepared via the steam jet mill is longer than that of traditional desulfurizers,and has significant advantages,especially at low flue gas relative *** with traditional desulfurizers,the desulfurizer prepared via steam jet mill expands the range of acceptable flue gas temperature,and the failure temperature is 1.625 times that of traditional *** work breaks through the technical bottleneck of low dry desulfurization efficiency,which is an important step in pushing forward the application of dry desulfurization.

关键词： Dry desulfurization Relative humidity Desulfurization efficiency High-efficiency desulfurizer Quicklime digestion

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A resonant high-pressure microsensor based on a composite pressure-sensitive mechanism of diaphragm bending and volume compression

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Microsystems & Nanoengineering 2024年第2期10卷 57-66页

作者： Pan Qian Zongze yu Jie yu yulan Lu Bo Xie Jian chen Deyong chen Junbo Wang The State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing100190China The School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing100049China

In this paper,a composite pressure-sensitive mechanism combining diaphragm bending and volume compression was developed for resonant pressure microsensors to achieve high-pressure measurements with excellent *** composite mechanism was explained,and the sensor structure was designed based on theoretical analysis and finite element *** all-silicon resonant high-pressure microsensor with multiple miniaturized cavities and dual resonators was developed,where dual resonators positioned in two resonant cavities with suitably different widths are used to perform opposite characteristics in pressure and the same characteristics at different temperatures,which can improve pressure sensitivities and realize temperature self-compensation by differential frequency *** microsensor was fabricated by microfabrication,and the experimental results showed that the sensor had an accuracy of±0.015%full scale(FS)in a pressure range of 0.1~100 MPa and a temperature range of−10~50℃.The pressure sensitivity of the differential frequency was 261.10 Hz/MPa(~2523 ppm/MPa)at a temperature of 20℃,and the temperature sensitivities of the dual resonators were−1.54 Hz/℃(~−14.5 ppm/℃)and−1.57 Hz/℃(~−15.6 ppm/℃)at a pressure of 2 *** differential output had an outstanding stability within±0.02 Hz under constant temperature and ***,this research provides a convenient solution for high-pressure measurements because of its advantages,namely,large range,excellent accuracy and stability.

关键词： stability resonant bending

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Wind-Vortex-Induced Vibrations of a Deepwater Jacket Pipe and Vibration Suppression Using a Nonlinear Energy Sink

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Journal of Ocean University of China 2024年第3期23卷 633-642页

作者： LIU Liqin yu Yongjun chen Yiqun State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China China Classification Society Haikou 570102China

The purpose of this study is to investigate the suppression effect of a nonlinear energy sink(NES)on the wind-vortex-induced pipe vibration and explore the influence of damping,stiffness,and NES installation position on the suppression *** this work,the wind-vortex-induced vibration of an elastic pipe of a deepwater jacket was studied,and vibrations were suppressed by using an NES.A van der Pol wake oscillator was used to simulate vortex-induced force,and the dynamic equation of the pipe considering the NES was *** Galerkin method was applied to discretize the motion equation,and the vortex-induced vibration(VIV)of the pipe at reduced wind speeds was numerically *** novelty of this research is that particle swarm optimization was used to optimize the parameters of the NES to improve vibration *** influence of the installation position,nonlinear stiffness,and damping parameters of the NES on vibration suppression was *** showed that the optimized parameter combinations of the NES can effectively reduce wind-vortex-induced pipe *** installation position of the NES had a significant effect on vibration suppression,and the midpoint of the pipe was the optimal NES installation *** increase in stiffness or a 10% decrease in damping may cause vibration suppression *** results of this study provide some guidance for VIV suppression in deepwater jacket pipes.

关键词： deepwater jacket wind-vortex-induced vibration NES PSO vibration suppression effect analysis

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Escape probability for isotropic emitters near Kerr black hole with astrometric

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Communications in Theoretical Physics 2024年第5期76卷 128-133页

作者： yu-Xuan Han Qing-Hua zhu Qing-Guo Huang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesNo.19A Yuquan RoadBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced Study UCASHangzhou 310024China

The paper investigates the escape probability for isotropic emitters near a Kerr black *** propose a new approach to obtain the escape probability in a general manner,going beyond previous case-by-case *** approach is based on studies of the black hole shadow with astrometric observable and can be applied to emitters with an arbitrary 4-velocities and locations,even to the emitters outside of the equatorial *** also consider representative examples illustrating how escape probabilities vary with distance,velocity,and inclination ***,this new approach provides an effective method for studying escape probabilities near Kerr black holes.

关键词： Kerr black hole photon escape probability isotropic emitters

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