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面向Critical MTC的无连接传输
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作者 李志岗 袁志锋 +2 位作者 董展谊 李文斌 梁楚龙 《中兴通讯技术》 北大核心 2024年第1期60-67,共8页
关键机器类通信(Critical MTC)对时延和可靠性都有极高的要求。支持海量Critical MTC的终端是一个巨大挑战。提出了一种面向海量Critical MTC终端的无连接传输方案。为了降低时延,提出了基于竞争的无连接单次传输方案;为了实现高可靠性... 关键机器类通信(Critical MTC)对时延和可靠性都有极高的要求。支持海量Critical MTC的终端是一个巨大挑战。提出了一种面向海量Critical MTC终端的无连接传输方案。为了降低时延,提出了基于竞争的无连接单次传输方案;为了实现高可靠性,设计了具有极低导频碰撞概率的稀疏正交多导频。进一步利用大规模多输入多输出(MIMO)的增益来提高可靠性以及在空域复用大量用户。仿真结果表明,提出的方案可以支持海量Critical MTC终端,同时满足低时延和高可靠的严格要求。 展开更多
关键词 无连接传输 critical MTC 低时延高可靠 导频碰撞 稀疏正交导频
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Semi-analytical solution for drained expansion analysis of a hollow cylinder of critical state soils 被引量:1
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作者 He Yang Jialiang Zhang +1 位作者 Haisui Yu Peizhi Zhuang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2326-2340,共15页
The expansion of a thick-walled hollow cylinder in soil is of non-self-similar nature that the stress/deformation paths are not the same for different soil material points.As a result,this problem cannot be solved by ... The expansion of a thick-walled hollow cylinder in soil is of non-self-similar nature that the stress/deformation paths are not the same for different soil material points.As a result,this problem cannot be solved by the common self-similar-based similarity techniques.This paper proposes a novel,exact solution for rigorous drained expansion analysis of a hollow cylinder of critical state soils.Considering stress-dependent elastic moduli of soils,new analytical stress and displacement solutions for the nonself-similar problem are developed taking the small strain assumption in the elastic zone.In the plastic zone,the cavity expansion response is formulated into a set of first-order partial differential equations(PDEs)with the combination use of Eulerian and Lagrangian descriptions,and a novel solution algorithm is developed to efficiently solve this complex boundary value problem.The solution is presented in a general form and thus can be useful for a wide range of soils.With the new solution,the non-self-similar nature induced by the finite outer boundary is clearly demonstrated and highlighted,which is found to be greatly different to the behaviour of cavity expansion in infinite soil mass.The present solution may serve as a benchmark for verifying the performance of advanced numerical techniques with critical state soil models and be used to capture the finite boundary effect for pressuremeter tests in small-sized calibration chambers. 展开更多
关键词 Cavity expansion Drained analysis Boundary effect critical state soil Non-self-similar Eulerian-Lagrangian approach
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Chord length sampling correction analysis for dispersion fuel in Monte Carlo simulation
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作者 Zhao-Yu Liang Ding She +1 位作者 Yu-Tong Wen Lei Shi 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期57-64,共8页
Dispersion fuels,knowned for their excellent safety performance,are widely used in advanced reactors,such as hightemperature gas-cooled reactors.Compared with deterministic methods,the Monte Carlo method has more adva... Dispersion fuels,knowned for their excellent safety performance,are widely used in advanced reactors,such as hightemperature gas-cooled reactors.Compared with deterministic methods,the Monte Carlo method has more advantages in the geometric modeling of stochastic media.The explicit modeling method has high computational accuracy and high computational cost.The chord length sampling(CLS)method can improve computational efficiency by sampling the chord length during neutron transport using the matrix chord length?s probability density function.This study shows that the excluded-volume effect in realistic stochastic media can introduce certain deviations into the CLS.A chord length correction approach is proposed to obtain the chord length correction factor by developing the Particle code based on equivalent transmission probability.Through numerical analysis against reference solutions from explicit modeling in the RMC code,it was demonstrated that CLS with the proposed correction method provides good accuracy for addressing the excludedvolume effect in realistic infinite stochastic media. 展开更多
关键词 Stochastic media Monte Carlo Chord length sampling Excluded-volume effect Chord length correction
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Predicted Critical State Based on Invariance of the Lyapunov Exponent in Dual Spaces
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作者 刘通 夏旭 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第1期68-76,共9页
Critical states in disordered systems,fascinating and subtle eigenstates,have attracted a lot of research interests.However,the nature of critical states is difficult to describe quantitatively,and in general,it canno... Critical states in disordered systems,fascinating and subtle eigenstates,have attracted a lot of research interests.However,the nature of critical states is difficult to describe quantitatively,and in general,it cannot predict a system that hosts the critical state.We propose an explicit criterion whereby the Lyapunov exponent of the critical state should be 0 simultaneously in dual spaces,namely the Lyapunov exponent remains invariant under the Fourier transform.With this criterion,we can exactly predict a one-dimensional quasiperiodic model which is not of self-duality,but hosts a large number of critical states.Then,we perform numerical verification of the theoretical prediction and display the self-similarity of the critical state.Due to computational complexity,calculations are not performed for higher dimensional models.However,since the description of extended and localized states by the Lyapunov exponent is universal and dimensionless,utilizing the Lyapunov exponent of dual spaces to describe critical states should also be universal.Finally,we conjecture that some kind of connection exists between the invariance of the Lyapunov exponent and conformal invariance,which can promote the research of critical phenomena. 展开更多
关键词 STATE EXPONENT critical
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Engineering Quantum Criticality for Quantum Dot Power Harvesting
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作者 王金义 年磊磊 吕京涛 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期14-25,共12页
Coupling of quantum-dot circuits to microwave photons enables us to investigate photon-assisted quantum transport.Here,we revisit this typical circuit quantum electrodynamical setup by introducing the Kerr nonlinearit... Coupling of quantum-dot circuits to microwave photons enables us to investigate photon-assisted quantum transport.Here,we revisit this typical circuit quantum electrodynamical setup by introducing the Kerr nonlinearity of photons.By exploiting quantum critical behavior,we propose a powerful scheme to control the power-harvesting efficiency in the microwave regime,where the driven-dissipative optical system acts as an energy pump.It drives electron transport against a load in the quantum-dot circuit.The energy transfer and,consequently,the harvesting efficiency are enhanced near the critical point.As the critical point moves towards to low input power,high efficiency within experimental parameters is achieved.Our results complement fundamental studies of photon-to-electron conversion at the nanoscale and provide practical guidance for designs of integrated photoelectric devices through quantum criticality. 展开更多
关键词 QUANTUM critical MICROWAVE
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Anisotropic s-Wave Gap in the Vicinity of a Quantum Critical Point in Superconducting BaFe_(2)(As_(1-x)P_(x))_(2) Single Crystals:A Study of Point-Contact Spectroscopy
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作者 詹红星 林玉尺 +8 位作者 赵宇清 左海艳 王兴玉 马肖燕 李春红 罗会仟 陈根富 李世亮 任聪 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期118-123,共6页
We report on soft c-axis point-contact Andreev reflection(PCAR)spectroscopy combining with resistivity measurements on BaFe_(2)(As_(0.7)P_(0.3))_(2),to elucidate the superconducting gap structure in the vicinity of th... We report on soft c-axis point-contact Andreev reflection(PCAR)spectroscopy combining with resistivity measurements on BaFe_(2)(As_(0.7)P_(0.3))_(2),to elucidate the superconducting gap structure in the vicinity of the quantum critical point.A double peak at the gap edge plus a dip feature at zero-bias has been observed on the PCAR spectra,indicative of the presence of a nodeless gap in BaFe_(2)(As_(0.7)P_(0.3))_(2).Detailed analysis within a sophisticated theoretical model reveals an anisotropic gap with deep gap minima.The PCARs also feature additional structures related to the electron-bosonic coupling mode.Using the extracted superconducting energy gap value,a characteristic bosonic energy Ω_(b) and its temperature dependence are obtained,comparable with the spin-resonance energy observed in neutron scattering experiment.These results indicate a magnetism-driven quantum critical point in the BaFe_(2)(As_(1-x)P_(x))_(2) system. 展开更多
关键词 quantum critical RESISTIVITY
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Unlocking hypoglycemia–associated brain microvascular dysfunction:critical insights from proteomic analysis
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作者 Siva S.V.P.Sakamuri Anil Sakamuri 《Neural Regeneration Research》 SCIE CAS 2025年第6期1707-1708,共2页
Hypoglycemia-a critical complication linked to worsened brain function in diabetic subjects:Hypoglycemia is characterized by a decline in circulatory glucose levels below sta nda rd physiological thresholds.Mild hypog... Hypoglycemia-a critical complication linked to worsened brain function in diabetic subjects:Hypoglycemia is characterized by a decline in circulatory glucose levels below sta nda rd physiological thresholds.Mild hypoglycemia,classified as level 1 hypoglycemia,is defined by blood glucose levels below 70 mg/dL and can be effectively addressed through carbohydrate intake.Severe hypoglycemia,denoted by blood glucose levels less than 54 mg/dL,poses a life-threatening risk if left untreated.Individuals with type 1 and type 2 diabetes undergoing insulin treatment are particularly susceptible to hypoglycemia due to impaired counterregulatory mechanisms. 展开更多
关键词 IMPAIRED INTAKE critical
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Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density
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作者 J.Cikhardt M.Gyrdymov +9 位作者 S.Zähter P.Tavana M.M.Günther N.Bukharskii N.Borisenko J.Jacoby X.F.Shen A.Pukhov N.E.Andreev O.N.Rosmej 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第2期26-35,共10页
Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the ... Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 MeV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an FWHM of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities. 展开更多
关键词 laser ACCELERATION critical
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Phenotypic Characterization and QTL/Gene Identification for Internode Number and Length Related Traits in Maize
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作者 Jing Li Fengjuan Gu +10 位作者 Guoqiang Wang Yingyi Zhang Xiangling Gong Wei Wei Xianchuang Zhang Lin Liu Hameed Gul Hong Duan Chaoxian Liu Qianlin Xiao Zhizhai Liu 《American Journal of Plant Sciences》 CAS 2024年第7期467-485,共19页
Internode number and length are the foundation to constitute plant height, ear height and the above-ground spatial structure of maize plant. In this study, segregating populations were constructed between EHel with ex... Internode number and length are the foundation to constitute plant height, ear height and the above-ground spatial structure of maize plant. In this study, segregating populations were constructed between EHel with extremely low ear height and B73. Through the SNP-based genotyping and phenotypic characterization, 13 QTL distributed on the chromosomes (Chrs) of Chr1, Chr2, Chr5-Chr8 were detected for four traits of internode no. above ear (INa), average internode length above ear (ILaa), internode no. below ear (INb), and average internode length below ear (ILab). Phenotypic variation explained (PVE) by a single QTL ranged from 6.82% (qILab2-2) to 12.99% (qILaa5). Zm00001d016823 within the physical region of qILaa5, the major QTL for ILaa with the largest PVE was determined as the candidate through the genomic annotation and sequence alignment between EHel and B73. Product of Zm00001d016823 was annotated as a WEB family protein homogenous to At1g75720. qRT-PCR assay showed that Zm00001d016823 highly expressed within the tissue of internode, exhibiting statistically higher expression levels among internodes of IN4 to IN7 in EHel than those in B73 (P Zm00001d016823 might provide novel insight into molecular mechanism beyond phytohormones controlling internode development in maize. 展开更多
关键词 Maize (Zea mays L.) Internode No. Average Internode length Phenotypic Characterization Candidate Gene Discovery
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Exploring Critical Thinking Dispositions among Fourth Year BSc Nursing Students of Various Colleges of Nursing, Pakistan
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作者 Sadaf Younis Najma Balquees Anwar Syeda Fakhar Batool 《Open Journal of Nursing》 2024年第6期267-281,共15页
Background: Critical Thinking (CT) dispositions in nursing are prominent predictors of competence in delivering high-quality care, and of professionalism, in newly graduated nurses. CT skills, in isolation of CT dispo... Background: Critical Thinking (CT) dispositions in nursing are prominent predictors of competence in delivering high-quality care, and of professionalism, in newly graduated nurses. CT skills, in isolation of CT dispositions, do not guarantee success in the workplace, because Critical Thinking Dispositions (CTD) are important elements of intellectual reasoning that simulate a person towards using the CT skills. Therefore, nursing educational programs should promote lifelong learning rather than focusing on transferring the content of nursing knowledge only. And for this purpose, quality education is the key. Education should focus on teaching from diverse perspectives, incorporating various teaching learning strategies that are congruent with the modern era. Purpose: The purpose of this study is to explore critical thinking dispositions among final year Baccalaureate Nursing students of various military colleges of nursing, in Pakistan. Methodology: A descriptive qualitative exploratory study design was used to investigate the CTD of BSc final year nursing students. The study population included twelve willing nursing students, from six military colleges across the country. Demographic information and consent was taken from the participants of the study. In-depth interviews, through a semi structured interview guide, and probes were used to obtain data related to personal experiences of CTD amongst the nursing students. Results: Data analysis showed two broad themes: 1) Perceptions of CT, and 2) Experiences of CT dispositions. In theme one, the emerging category was: Clarity of CT;whereas in theme two, the categories that emerged were: a) Truth Seeking, b) Open Mindedness, c) Inquisitiveness, and d) Self Organization. Conclusion: The findings of the study revealed positive dispositions towards truth seeking, open mindedness, and self-organization, whereas disposition towards inquisitiveness was weak. Self-confidence and maturity also emerged as positive factors that the students possessed. This study recommends that faculty and learners should extend their concept of CTD, and emphasizes its application in daily routine. Additionally, faculty should modify their instructional strategies and focus on the cultivation of dispositions of inquisitiveness, curiosity, and allow questioning by students in the class. 展开更多
关键词 critical Thinking critical Thinking Disposition Nursing Students
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Aerodynamic Features of High-Speed Maglev Trains with Different Marshaling Lengths Running on a Viaduct under Crosswinds
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作者 Zun-Di Huang Zhen-Bin Zhou +2 位作者 Ning Chang Zheng-Wei Chen Su-Mei Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期975-996,共22页
The safety and stability of high-speed maglev trains traveling on viaducts in crosswinds critically depend on their aerodynamic characteristics.Therefore,this paper uses an improved delayed detached eddy simulation(ID... The safety and stability of high-speed maglev trains traveling on viaducts in crosswinds critically depend on their aerodynamic characteristics.Therefore,this paper uses an improved delayed detached eddy simulation(IDDES)method to investigate the aerodynamic features of high-speed maglev trains with different marshaling lengths under crosswinds.The effects of marshaling lengths(varying from 3-car to 8-car groups)on the train’s aerodynamic performance,surface pressure,and the flow field surrounding the train were investigated using the three-dimensional unsteady compressible Navier-Stokes(N-S)equations.The results showed that the marshaling lengths had minimal influence on the aerodynamic performance of the head and middle cars.Conversely,the marshaling lengths are negatively correlated with the time-average side force coefficient(CS)and time-average lift force coefficient(Cl)of the tail car.Compared to the tail car of the 3-car groups,the CS and Cl fell by 27.77%and 18.29%,respectively,for the tail car of the 8-car groups.It is essential to pay more attention to the operational safety of the head car,as it exhibits the highest time average CS.Additionally,the mean pressure difference between the two sides of the tail car body increased with the marshaling lengths,and the side force direction on the tail car was opposite to that of the head and middle cars.Furthermore,the turbulent kinetic energy of the wake structure on the windward side quickly decreased as marshaling lengths increased. 展开更多
关键词 High-speed maglev train marshaling lengths crosswinds aerodynamic features
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Impact of multifocal gas-permeable lens designs on short-term choroidal response, axial length, and retinal defocus profile
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作者 Muteb Alanazi Patrick Caroline +1 位作者 Amane Alshamrani Maria Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期247-256,共10页
AIM:To investigate the impact of multifocal gas permeable contact lens(MFGPCL)in various add power and distance/near area allocation on short-term changes of choroidal thickness(ChT),axial length(AL),and retinal defoc... AIM:To investigate the impact of multifocal gas permeable contact lens(MFGPCL)in various add power and distance/near area allocation on short-term changes of choroidal thickness(ChT),axial length(AL),and retinal defocus profile in young adults.METHODS:Seventeen young adults(2 males and 15 females;age 23.17±4.48y)were randomly assigned to wear two designs binocularly with a one-week washout period in between.Total of four MFGPCL designs were assessed.All designs were distance-center that varied in two add power(+1.50 and 3.00 D)and/or two distance zone(DZ)diameters(1.50 and 3.00 mm;design A:DZ 1.5/add 3.0,B:DZ 1.5/add 1.5,C:DZ 3.0/add 3.0,D:DZ 3.0/add 1.5).ChT,AL,and peripheral refraction data were collected on each subject at baseline,on days 1 and 7 of MFGPCL daily wear.ChT was assessed in four quadrants using a spectraldomain optical coherence tomography.RESULTS:AL was shortened by-26±44μm with lens C,-18±27μm with lens D,-13±29μm with lens A,and-8±30μm with lens B(all P<0.05).A significant overall increase in ChT was observed with all 4 designs(lens A:+6±6μm,B:+3±7μm,C:+8±7μm,and D:+8±7μm).Temporal and superior choroid exhibited more choroidal thickening associated with MFGPCL.All designs induced significant relative peripheral myopia(RPM)beyond the central 20o across the horizontal meridian in both nasal and temporal fields(P<0.05).CONCLUSION:MFGPCLs show a significant influence on ChT and AL,which are associated with significant increase in RPM after short-term wear.The reliability and feasibility of quantifying short-term changes in ChT support its use as a promising marker for the long-term efficacy of myopia-controlling treatments. 展开更多
关键词 CHOROID gas-permeable contact lens retinal defocus axial length MYOPIA
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Critical behavior of quasi-two-dimensional ferromagnet Cr_(1.04)Te_(2)
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作者 钮伟 宋沁心 +10 位作者 常世琦 王敏 袁奎 高嘉程 王硕 王振东 刘凯斐 刘萍 徐永兵 张晓倩 普勇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期87-94,共8页
The self-intercalation of Cr into pristine two-dimensional(2D) van der Waals ferromagnetic CrTe_(2),which forms chromium tellurides(Cr_(x)Te_(2)),has garnered interest due to their remarkable magnetic characteristics ... The self-intercalation of Cr into pristine two-dimensional(2D) van der Waals ferromagnetic CrTe_(2),which forms chromium tellurides(Cr_(x)Te_(2)),has garnered interest due to their remarkable magnetic characteristics and the wide variety of chemical compositions available.Here,comprehensive basic characterization and magnetic studies are conducted on quasi-2D ferromagnetic Cr_(1.04)Te_(2) crystals.Measurements of the isothermal magnetization curves are conducted around the critical temperature to systematically investigate the critical behavior.Specifically,the critical exponents β=0.2399,γ=0.859,and δ=4.3498,as well as the Curie temperature T_(C)=249.56 K,are determined using various methods,including the modified Arrott plots,the Kouvel-Fisher method,the Widom scaling method,and the critical isotherm analysis.These results indicate that the tricritical mean-field model accurately represents the critical behavior of Cr_(1.04)Te_(2.A magnetic phase diagram with tricritical phenomenon is thus constructed.Further investigations confirm that the critical exponents obtained conform to the scalar equation near T_(C),indicating their self-consistency and reliability.Our work sheds light on the magnetic properties of quasi-2D Cr_(1.04)Te_(2),broadening the scope of the van der Waals crystals for developments of future spintronic devices operable at room temperature. 展开更多
关键词 critical behavior van der Waals magnets self-intercalation magnetic measurement
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Exploring the Implications of the Deformation Parameter and Minimal Length in the Generalized Uncertainty Principle
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作者 Mahgoub A. Salih Taysir M. Elmahdi 《Journal of Quantum Information Science》 CAS 2024年第1期1-14,共14页
The breakdown of the Heisenberg Uncertainty Principle occurs when energies approach the Planck scale, and the corresponding Schwarzschild radius becomes similar to the Compton wavelength. Both of these quantities are ... The breakdown of the Heisenberg Uncertainty Principle occurs when energies approach the Planck scale, and the corresponding Schwarzschild radius becomes similar to the Compton wavelength. Both of these quantities are approximately equal to the Planck length. In this context, we have introduced a model that utilizes a combination of Schwarzschild’s radius and Compton length to quantify the gravitational length of an object. This model has provided a novel perspective in generalizing the uncertainty principle. Furthermore, it has elucidated the significance of the deforming linear parameter β and its range of variation from unity to its maximum value. 展开更多
关键词 Generalized Uncertainty Principle Deformed Heisenberg Algebra Minimal length
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Predictive modeling of critical temperatures in magnesium compounds using transfer learning
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作者 Surjeet Kumar Russlan Jaafreh +4 位作者 Subhajit Dutta Jung Hyeon Yoo Santiago Pereznieto Kotiba Hamad Dae Ho Yoon 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1540-1553,共14页
This study presents a transfer learning approach for discovering potential Mg-based superconductors utilizing a comprehensive target dataset.Initially,a large source dataset(Bandgap dataset)comprising approximately∼7... This study presents a transfer learning approach for discovering potential Mg-based superconductors utilizing a comprehensive target dataset.Initially,a large source dataset(Bandgap dataset)comprising approximately∼75k compounds is utilized for pretraining,followed by fine-tuning with a smaller Critical Temperature(T_(c))dataset containing∼300 compounds.Comparatively,there is a significant improvement in the performance of the transfer learning model over the traditional deep learning(DL)model in predicting Tc.Subsequently,the transfer learning model is applied to predict the properties of approximately 150k compounds.Predictions are validated computationally using density functional theory(DFT)calculations based on lattice dynamics-related theory.Moreover,to demonstrate the extended predictive capability of the transfer learning model for new materials,a pool of virtual compounds derived from prototype crystal structures from the Materials Project(MP)database is generated.T_(c) predictions are obtained for∼3600 virtual compounds,which underwent screening for electroneutrality and thermodynamic stability.An Extra Trees-based model is trained to utilize E_(hull)values to obtain thermodynamically stable materials,employing a dataset containing Ehull values for approximately 150k materials for training.Materials with Ehull values exceeding 5 meV/atom were filtered out,resulting in a refined list of potential Mg-based superconductors.This study showcases the effectiveness of transfer learning in predicting superconducting properties and highlights its potential for accelerating the discovery of Mg-based materials in the field of superconductivity. 展开更多
关键词 SUPERCONDUCTIVITY critical temperature Transfer learning Crystal structure features Thermodynamic stability
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Accelerating Oxygen Electrocatalysis Kinetics on Metal-Organic Frameworks via Bond Length Optimization
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作者 Fan He Yingnan Liu +10 位作者 Xiaoxuan Yang Yaqi Chen Cheng‑Chieh Yang Chung‑Li Dong Qinggang He Bin Yang Zhongjian Li Yongbo Kuang Lecheng Lei Liming Dai Yang Hou 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期279-290,共12页
Metal-organic frameworks(MOFs)have been developed as an ideal platform for exploration of the relationship between intrinsic structure and catalytic activity,but the limited catalytic activity and stability has hamper... Metal-organic frameworks(MOFs)have been developed as an ideal platform for exploration of the relationship between intrinsic structure and catalytic activity,but the limited catalytic activity and stability has hampered their practical use in water splitting.Herein,we develop a bond length adjustment strategy for optimizing naphthalene-based MOFs that synthesized by acid etching Co-naphthalenedicarboxylic acid-based MOFs(donated as AE-CoNDA)to serve as efficient catalyst for water splitting.AE-CoNDA exhibits a low overpotential of 260 mV to reach 10 mA cm^(−2)and a small Tafel slope of 62 mV dec^(−1)with excellent stability over 100 h.After integrated AE-CoNDA onto BiVO_(4),photocurrent density of 4.3 mA cm^(−2)is achieved at 1.23 V.Experimental investigations demonstrate that the stretched Co-O bond length was found to optimize the orbitals hybridization of Co 3d and O 2p,which accounts for the fast kinetics and high activity.Theoretical calculations reveal that the stretched Co-O bond length strengthens the adsorption of oxygen-contained intermediates at the Co active sites for highly efficient water splitting. 展开更多
关键词 Metal-organic frameworks Bond length adjustment Spin state transition Orbitals hybridization Water splitting
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Mental health status among COVID-19 patients survivors of critical illness in Saudi Arabia:A 6-month follow-up questionnaire study
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作者 Abdullah M Alhammad Namareq F Aldardeer +10 位作者 Abdulaziz Alqahtani Mohammad H Aljawadi Bushra Alnefaie Raghad Alonazi Mansour Almuqbil Abdulrahman Alsaadon Rakan M Alqahtani Rashid Alballaa Bader Alshehri Mohammed I Alarifi Fahad D Alosaimi 《World Journal of Clinical Cases》 SCIE 2024年第15期2560-2567,共8页
BACKGROUND Psychological assessment after intensive care unit(ICU)discharge is increasingly used to assess patients'cognitive and psychological well-being.However,few studies have examined those who recovered from... BACKGROUND Psychological assessment after intensive care unit(ICU)discharge is increasingly used to assess patients'cognitive and psychological well-being.However,few studies have examined those who recovered from coronavirus disease 2019(COVID-19).There is a paucity of data from the Middle East assessing the post-ICU discharge mental health status of patients who had COVID-19.AIM To evaluate anxiety and depression among patients who had severe COVID-19.METHODS This is a prospective single-center follow-up questionnaire-based study of adults who were admitted to the ICU or under ICU consultation for>24 h for COVID-19.Eligible patients were contacted via telephone.The patient’s anxiety and depression six months after ICU discharge were assessed using the Hospital Anxiety and Depression Scale(HADS).The primary outcome was the mean HADS score.The secondary outcomes were risk factors of anxiety and/or depression.RESULTS Patients who were admitted to the ICU because of COVID-19 were screened(n=518).Of these,48 completed the questionnaires.The mean age was 56.3±17.2 years.Thirty patients(62.5%)were male.The main comorbidities were endocrine(n=24,50%)and cardiovascular(n=21,43.8%)diseases.The mean overall HADS score for anxiety and depression at 6 months post-ICU discharge was 11.4(SD±8.5).A HADS score of>7 for anxiety and depression was detected in 15 patients(30%)and 18 patients(36%),respectively.Results from the multivariable ordered logistic regression demonstrated that vasopressor use was associated with the development of anxiety and depression[odds ratio(OR)39.06,95% confidence interval:1.309-1165.8;P<0.05].CONCLUSION Six months after ICU discharge,30% of patients who had COVID-19 demonstrated a HADS score that confirmed anxiety and depression.To compare the psychological status of patients following an ICU admission(with vs without COVID-19),further studies are warranted. 展开更多
关键词 COVID-19 critically ill ANXIETY DEPRESSION HADS Saudi Arabia
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Critical Solvation Structures Arrested Active Molecules for Reversible Zn Electrochemistry
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作者 Junjie Zheng Bao Zhang +14 位作者 Xin Chen Wenyu Hao Jia Yao Jingying Li Yi Gan Xiaofang Wang Xingtai Liu Ziang Wu Youwei Liu Lin Lv Li Tao Pei Liang Xiao Ji Hao Wang Houzhao Wan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期64-78,共15页
Aqueous Zn-ion batteries(AZIBs)have attracted increasing attention in next-generation energy storage systems due to their high safety and economic.Unfortunately,the side reactions,dendrites and hydrogen evolution effe... Aqueous Zn-ion batteries(AZIBs)have attracted increasing attention in next-generation energy storage systems due to their high safety and economic.Unfortunately,the side reactions,dendrites and hydrogen evolution effects at the zinc anode interface in aqueous electrolytes seriously hinder the application of aqueous zinc-ion batteries.Here,we report a critical solvation strategy to achieve reversible zinc electrochemistry by introducing a small polar molecule acetonitrile to form a“catcher”to arrest active molecules(bound water molecules).The stable solvation structure of[Zn(H_(2)O)_(6)]^(2+)is capable of maintaining and completely inhibiting free water molecules.When[Zn(H_(2)O)_(6)]^(2+)is partially desolvated in the Helmholtz outer layer,the separated active molecules will be arrested by the“catcher”formed by the strong hydrogen bond N-H bond,ensuring the stable desolvation of Zn^(2+).The Zn||Zn symmetric battery can stably cycle for 2250 h at 1 mAh cm^(-2),Zn||V_(6)O_(13) full battery achieved a capacity retention rate of 99.2%after 10,000 cycles at 10 A g^(-1).This paper proposes a novel critical solvation strategy that paves the route for the construction of high-performance AZIBs. 展开更多
关键词 Zinc-ion battery critical solvation Helmholtz layer Arrest active molecule Reversible zinc anode
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MULTIPLE SOLUTIONS TO CRITICAL MAGNETIC SCHR?DINGER EQUATIONS
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作者 Ruijiang WEN Jianfu YANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1373-1393,共21页
In this paper,we are concerned with the existence of multiple solutions to the critical magnetic Schr?dinger equation(-i▽-a(x))^(2)u+⒂λV(x)u=p|u|^(p-2)u+(∫R(n)|u(y)|^(2)_(a)^(*)/|x-y|^(a)dy)|u|2_(a)^(*)-2_(u)in R^... In this paper,we are concerned with the existence of multiple solutions to the critical magnetic Schr?dinger equation(-i▽-a(x))^(2)u+⒂λV(x)u=p|u|^(p-2)u+(∫R(n)|u(y)|^(2)_(a)^(*)/|x-y|^(a)dy)|u|2_(a)^(*)-2_(u)in R^(N),(0.1)where N≥4,2≤p<2^(*),2_α^(*)=(2N-α)/(N-2)with 0<α<4,λ>0,μ∈R,A(x)=(A_(1)(x),A_(2)(x),…,A_(N)(x))is a real local Hölder continuous vector function,i is the imaginary unit,and V(x)is a real valued potential function on R^(N).Supposing thatΩ=int V^(-1)(0)■R^(N)is bounded,we show that problem(0.1)possesses at least cat_(Ω)(Ω)nontrivial solutions ifλis large. 展开更多
关键词 critical magnetic Schr?dinger equation multiple solutions Ljusternik-Schnirelman theory
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Interrelationships between Length of the Day, Moon Distance, Phanerozoic Geodynamic Cycles, Tidal Dissipation and Earth’s Core: Review and Analysis
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作者 Heinz-Jürgen Brink 《International Journal of Geosciences》 CAS 2024年第5期396-415,共20页
The rotation of the Earth and the related length of the day (LOD) are predominantly affected by tidal dissipation through the Moon and the growth of the Earth’s core. Due to the increased concentration of mass around... The rotation of the Earth and the related length of the day (LOD) are predominantly affected by tidal dissipation through the Moon and the growth of the Earth’s core. Due to the increased concentration of mass around the rotation axis of the spinning Earth during the growth of the core the rotation should have been accelerated. Controversially the tidal dissipation by the Moon, which is mainly dependent on the availability of open shallow seas and the kind of Moon escape from a nearby position, acts towards a deceleration of the rotating Earth. Measurements of LOD for Phanerozoic and Precambrian times open ways to solve questions concerning the geodynamical history of the Earth. These measurements encompass investigations of growth patterns in fossils and depositional patterns in sediments (Cyclostratigraphy, Tidalites, Stromatolites, Rhythmites). These patterns contain information on the LOD and on the changing distance between Earth and Moon and can be used as well for a discussion about the growth of the Earth’s core. By updating an older paper with its simple approach as well as incorporating newly published results provided by the geoscientific community, a moderate to fast growth of the core in a hot early Earth will be favored controversially to the assumption of a delayed development of the core in an originally cold Earth. Core development with acceleration of Earth’s rotation and the contemporaneous slowing down due to tidal dissipation during the filling of the ocean may significantly interrelate. 展开更多
关键词 length of the Day Moon Distance Phanerozoic Geodynamic Cycles Tidal Dissipation Earth’s Core
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