期刊文献+
共找到85,858篇文章
< 1 2 250 >
每页显示 20 50 100
Study on the adsorptive denitrification performance of MIL-101(Cr) and its theoretical calculation
1
作者 QIN Yue TANG Ke +3 位作者 HONG Xin WANG Han SHEN Shuo CHEN Jinghui 《燃料化学学报(中英文)》 北大核心 2026年第2期180-192,共13页
The adsorptive denitrification performance of MIL-101(Cr)-0.5 toward pyridine,aniline or quinoline in simulated fuels with basic nitrogen content of 1732μg/g was evaluated separately.Furthermore,the effects of adsorp... The adsorptive denitrification performance of MIL-101(Cr)-0.5 toward pyridine,aniline or quinoline in simulated fuels with basic nitrogen content of 1732μg/g was evaluated separately.Furthermore,the effects of adsorption temperature,adsorption time and adsorbent dosage on their adsorptive denitrification performance were systematically investigated.The experimental results demonstrated that under a fixed adsorbent dosage of 0.05 g and a simulated fuel volume of 10 mL,the optimal removal efficiency for aniline was achieved at 30℃ within 30 min,whereas higher temperatures and longer times(40℃and 40 min)were required for effective removal of pyridine and quinoline.Density Functional Theory(DFT)calculations were conducted via Materials Studio(MS)software to study the adsorptive denitrification mechanism of MIL-101(Cr)toward these three basic nitrogen-containing compounds.The simulation calculation results revealed that the interaction between pyridine and MIL-101(Cr)primarily involved coordination adsorption.In contrast,the interaction between aniline or quinoline and MIL-101(Cr)proceeded mainly through coordination,with additional contributions fromπ-complexation and hydrogen bonding.The overall adsorption strength order is pyridine>aniline>quinoline.During the adsorption process,pyridine and quinoline transfer electrons to the MIL-101(Cr)surface through the H→C→N→Cr^(3+)pathway,while aniline transfers electrons to the MIL-101(Cr)surface through various pathways,including N→Cr^(3+),N→C→Cr^(3+)and N→H→O.Furthermore,adsorption kinetics studies indicated that the adsorption processes for all three basic nitrogen-containing compounds followed the quasi second order kinetic models.The experimental results on the effect of benzene on the adsorptive denitrification performance of MIL-101(Cr)-0.5 demonstrated that benzene exerted a more significant impact on the adsorption of aniline and quinoline.Finally,the adsorbent was regenerated using ethanol washing.It was found that MIL-101(Cr)-0.5 retained stable denitrification performance after two regeneration cycles. 展开更多
关键词 MIL-101(Cr) adsorptive denitrification competitive adsorption regeneration performance simulation calculation
在线阅读 下载PDF
Multiscale Theoretical Calculations Empower Robust Electric Double Layer Toward Highly Reversible Zinc Anode
2
作者 Yufan Xia Zhen Luo +6 位作者 Shuang Chen Yang Xiang Gao Weng Hongge Pan Ben Bin Xu Mi Yan Yinzhu Jiang 《Nano-Micro Letters》 2026年第3期406-427,共22页
The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter per... The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter persistent dendrite growth and parasitic reactions,driven by the inhomogeneous charge distribution and water-dominated environment within the EDL.Compounding this,classical EDL theory,rooted in meanfield approximations,further fails to resolve molecular-scale interfacial dynamics under battery-operating conditions,limiting mechanistic insights.Herein,we established a multiscale theoretical calculation framework from single molecular characteristics to interfacial ion distribution,revealing the EDL’s structure and interactions between different ions and molecules,which helps us understand the parasitic processes in depth.Simulations demonstrate that water dipole and sulfate ion adsorption at the inner Helmholtz plane drives severe hydrogen evolution and by-product formation.Guided by these insights,we engineered a“water-poor and anion-expelled”EDL using 4,1’,6’-trichlorogalactosucrose(TGS)as an electrolyte additive.As a result,Zn||Zn symmetric cells with TGS exhibited stable cycling for over 4700 h under a current density of 1 mA cm^(−2),while NaV_(3)O_(8)·1.5H_(2)O-based full cells kept 90.4%of the initial specific capacity after 800 cycles at 5 A g^(−1).This work highlights the power of multiscale theoretical frameworks to unravel EDL complexities and guide high-performance ARZB design through integrated theory-experiment approaches. 展开更多
关键词 Zn anode Theoretical calculations Electric double layers Aqueous rechargeable zinc batteries
在线阅读 下载PDF
Thermodynamic performance calculation and test verification of gas-liquid two-phase water ramjet engine
3
作者 Pingan LIU Dianlong SUN +4 位作者 Xile QIAN Shang LIU Tao WANG Jingtao CHENG Kejing XU 《Chinese Journal of Aeronautics》 2026年第1期1-17,共17页
Underwater gas-liquid two-phase propulsion technology is an emerging propulsion method that offers high efficiency and unrestricted navigation speed.The integration of this technology into water ramjet engines can sig... Underwater gas-liquid two-phase propulsion technology is an emerging propulsion method that offers high efficiency and unrestricted navigation speed.The integration of this technology into water ramjet engines can significantly enhance propulsion efficiency and holds substantial potential for broad applications.However,forming a gas-liquid two-phase flow within the nozzle requires introducing a large amount of rammed seawater.At this time,there is a complex phase transition problem of combustion products in the combustion chamber,which makes the thermodynamic calculation for gas-liquid two-phase water ramjet engines particularly challenging.This paper proposes a thermodynamic calculation method for gas-liquid two-phase water ramjet engines,based on the energy equation for gas-liquid two-phase flow and traditional thermodynamic principles,enabling thermodynamic calculations under conditions of ultra-high water-fuel ratios.Additionally,ground ignition tests of the gas-liquid two-phase engine were conducted,yielding critical engine test parameters.The results demonstrate that the gas-liquid two-phase water ramjet engine achieves a high specific impulse,with a theoretical maximum specific impulse of up to 7000(N s)/kg.The multiphase flow effects significantly impact engine performance,with specific impulse losses reaching up to 25.86%.The error between the thrust and specific impulse in the ground test and the theoretical values is within 10%,validating the proposed thermodynamic calculation method as a reliable reference for further research on gas-liquid two-phase water ramjet engines. 展开更多
关键词 Gas-liquid two-phase flow Ignition test Multiphase flow Thermal calculation Water ramjet engine
原文传递
Cocrystal engineering for efficient separation of 4-bromo-3-methylphenol:Design of experiments,characterization,crystal structure and calculation
4
作者 Chunxiao Wang Shuai Wang +2 位作者 Hongsen Zhang Chao Li Renzhong Qiao 《Chinese Journal of Chemical Engineering》 2026年第1期83-92,共10页
4-Bromo-3-methylphenol(BMP)is an important chemical intermediate with wide applications in the fields of medicine and pesticides.The synthesis of BMP from m-cresol via bromination is easy to carry out on an industrial... 4-Bromo-3-methylphenol(BMP)is an important chemical intermediate with wide applications in the fields of medicine and pesticides.The synthesis of BMP from m-cresol via bromination is easy to carry out on an industrial scale.However,due to the formation of regioisomeric impurities during bromination and the low melting point of BMP,the separation process is prone to the formation of oily substances,resulting in low yield and purity.In this work,a new cocrystallization engineering approach was proposed to separate and purify BMP.Through design of experiments,the cocrystallization process of BMP and triethylenediamine(DABCO)was optimized using a minimum-run resolution IV screening design combined with response surface methodology.In addition,the obtained 2BMP-DABCO powder was characterized by thermal analysis,powder X-ray diffraction,infrared spectroscopy,and scanning electron microscopy.Single crystals of 2BMP-DABCO were grown from acetone by slow evaporation,and detailed structural information was obtained through single-crystal X-ray diffraction.The self-assembly mechanism was further clarified by density functional theory calculations.This study provides a simple,robust,and scalable method for the production of BMP and offers a reference for the separation and purification of phenolic substances. 展开更多
关键词 4-Bromo-3-methylphenol TRIETHYLENEDIAMINE Cocrystallization engineering Design of experiments Crystal structure calculationS
在线阅读 下载PDF
A Flexible-Segment-Model-Based Dynamics Calculation Method for Free Hanging Marine Risers in Re-Entry 被引量:10
5
作者 徐雪松 王盛炜 《China Ocean Engineering》 SCIE EI 2012年第1期139-152,共14页
In re-entry, the drilling riser hanging to the holding vessel takes on a free hanging state, waiting to be moved from the initial random position to the wellhead. For the re-entry, dynamics calculation is often done t... In re-entry, the drilling riser hanging to the holding vessel takes on a free hanging state, waiting to be moved from the initial random position to the wellhead. For the re-entry, dynamics calculation is often done to predict the riser motion or evaluate the structural safety. A dynamics calculation method based on Flexible Segment Model (FSM) is proposed for free hanging marine risers. In FSM, a riser is discretized into a series of flexible segments. For each flexible segment, its deflection feature and external forces are analyzed independently. For the whole riser, the nonlinear governing equations are listed according to the moment equilibrium at nodes. For the solution of the nonlinear equations, a linearization iteration scheme is provided in the paper. Owing to its flexibility, each segment can match a long part of the riser body, which enables that good results can be obtained even with a small number of segments. Moreover, the linearization iteration scheme can avoid widely used Newton-Rapson iteration scheme in which the calculation stability is influenced by the initial points. The FSM-based dynamics calculation is timesaving and stable, so suitable for the shape prediction or real-time control of free hanging marine risers. 展开更多
关键词 dynamics calculation discretization method free hanging marine riser riser re-entry
在线阅读 下载PDF
Research and Application Progress of Intraocular Lens Power Calculation Formulas in the Era of Refractive Cataract Surgery
6
作者 Bowei Liang Jinhua Wang +1 位作者 Yao Chen Pan Liu 《Journal of Biosciences and Medicines》 2025年第2期348-356,共9页
As cataract surgery progresses from “restoration of sight” to “refractive correction”, precise prediction of intraocular lens (IOL) power is critical for enhancing postoperative visual quality in patients. IOL pow... As cataract surgery progresses from “restoration of sight” to “refractive correction”, precise prediction of intraocular lens (IOL) power is critical for enhancing postoperative visual quality in patients. IOL power calculation methods have evolved and innovated throughout time, from early theoretical and regression formulas to nonlinear formulas for estimating effective lens position (ELP), multivariable formulas, and innovative formulas that use optical principles and AI-based online formulas. This paper thoroughly discusses the development and iteration of traditional IOL calculation formulas, the emergence of new IOL calculation formulas, and the selection of IOL calculation formulas for different patients in the era of refractive cataract surgery, serving as a reference for “personalized” IOL implantation in clinical practice. 展开更多
关键词 Cataract Surgery Intraocular Lens Power calculation Formula Refractive Cataract Lens Power calculation
在线阅读 下载PDF
Classification of forest vegetation with the application of iterative reallocation and model-based clustering
7
作者 Naghmeh Pakgohar Javad Eshaghi Rad +4 位作者 Hossein Gholami Ahmad Alijanpour David W.Roberts Attila Lengyel Enrico Feoli 《Journal of Forestry Research》 2025年第5期103-112,共10页
Numerous clustering algorithms are valuable in pattern recognition in forest vegetation,with new ones continually being proposed.While some are well-known,others are underutilized in vegetation science.This study comp... Numerous clustering algorithms are valuable in pattern recognition in forest vegetation,with new ones continually being proposed.While some are well-known,others are underutilized in vegetation science.This study compares the performance of practical iterative reallocation algorithms with model-based clustering algorithms.The data is from forest vegetation in Virginia(United States),the Hyrcanian Forest(Asia),and European beech forests.Practical iterative reallocation algorithms were applied as non-hierarchical methods and Finite Gaussian mixture modeling was used as a model-based clustering method.Due to limitations on dimensionality in model-based clustering,principal coordinates analysis was employed to reduce the dataset’s dimensions.A log transformation was applied to achieve a normal distribution for the pseudo-species data before calculating the Bray-Curtis dissimilarity.The findings indicate that the reallocation of misclassified objects based on silhouette width(OPTSIL)with Flexible-β(-0.25)had the highest mean among the tested clustering algorithms with Silhouette width 1(REMOS1)with Flexible-β(-0.25)second.However,model-based clustering performed poorly.Based on these results,it is recommended using OPTSIL with Flexible-β(-0.25)and REMOS1 with Flexible-β(-0.25)for forest vegetation classification instead of model-based clustering particularly for heterogeneous datasets common in forest vegetation community data. 展开更多
关键词 CLASSIFICATION Heuristic clustering Finite mixture Forest ecosystems model-based clustering
在线阅读 下载PDF
First-principles Calculations of the Mechanical,Electronic,and Thermodynamic Properties of Cubic Aluminumcopper Intermetallic Compounds under Pressure
8
作者 LUO Guoqiang ZHENG Aojun +3 位作者 GUO Chengcheng ZHOU Yiheng ZHANG Ruizhi ZHANG Jian 《Journal of Wuhan University of Technology(Materials Science)》 2025年第4期1126-1139,共14页
The effects of pressure on the structural stability,elasticity,electronic properties,and thermodynamic properties of Al,Al_(3)Cu,Al_(2)Cu,Al_(4)Cu_(9),AlCu_(3),and Cu were investigated using first-principles calculati... The effects of pressure on the structural stability,elasticity,electronic properties,and thermodynamic properties of Al,Al_(3)Cu,Al_(2)Cu,Al_(4)Cu_(9),AlCu_(3),and Cu were investigated using first-principles calculations.The experimental results indicate that the calculated equilibrium lattice constant,elastic constant,and elastic modulus agree with both theoretical and experimental data at 0 GPa.The Young's modulus,bulk modulus,and shear modulus increase with increasing pressure.The influence of pressure on mechanical properties is explained from a chemical bond perspective.By employing the quasi-harmonic approximation model of phonon calculation,the temperature and pressure dependence of thermodynamic parameters in the range of 0 to 800 K and 0 to 100 GPa are determined.The findings demonstrate that the thermal capacity and coefficient of thermal expansion increase with increasing temperature and decrease with increasing pressure.This study provides fundamental data and support for experimental investigations and further theoretical research on the properties of aluminum-copper intermetallic compounds. 展开更多
关键词 INTERMETALLICS ELASTICITY thermodynamic properties ab-initio calculations
原文传递
Model-Based System Multidisciplinary Design Optimization for Preliminary Design of a Blended Wing-Body Underwater Glider
9
作者 WANG Zhi-long LI Jing-lu +3 位作者 WANG Peng DONG Hua-chao WANG Xin-jing WEN Zhi-wen 《China Ocean Engineering》 2025年第4期755-767,共13页
Unlike traditional propeller-driven underwater vehicles,blended-wing-body underwater gliders(BWBUGs)achieve zigzag gliding through periodic adjustments of their net buoyancy,enhancing their cruising capabilities while... Unlike traditional propeller-driven underwater vehicles,blended-wing-body underwater gliders(BWBUGs)achieve zigzag gliding through periodic adjustments of their net buoyancy,enhancing their cruising capabilities while mini-mizing energy consumption.However,enhancing gliding performance is challenging due to the complex system design and limited design experience.To address this challenge,this paper introduces a model-based,multidisciplinary system design optimization method for BWBUGs at the conceptual design stage.First,a model-based,multidisciplinary co-simulation design framework is established to evaluate both system-level and disciplinary indices of BWBUG performance.A data-driven,many-objective multidisciplinary optimization is subsequently employed to explore the design space,yielding 32 Pareto optimal solutions.Finally,a model-based physical system simulation,which represents the design with the largest hyper-volume contribution among the 32 final designs,is established.Its gliding perfor-mance,validated by component behavior,lays the groundwork for constructing the entire system’s digital prototype.In conclusion,this model-based,multidisciplinary design optimization method effectively generates design schemes for innovative underwater vehicles,facilitating the development of digital prototypes. 展开更多
关键词 model-based design multidisciplinary design optimization data-driven optimization blended-wingbody underwater glider(BWBUG) physical system simulation
在线阅读 下载PDF
Wetting and interfacial behavior of high entropy alloy filler on rare earth silicate system:Phase analysis and first-principles calculations
10
作者 Shuai Zhao Buqiu Shao +6 位作者 Haiyan Chen Yuqi Hu Zhaoyi Pan Yongsheng Liu Pengcheng Wang Xiaoguo Song Wenya Li 《Journal of Materials Science & Technology》 2025年第30期223-238,共16页
The vacuum reactive wetting and brazing of Er_(2)Si_(2)O_(7)/MoSi_(2) coatings were investigated using a (CoFeNiCrMn)_(88)Nb_(12) high-entropy alloy (HEA) brazing filler. The microstructural evolution and wettability ... The vacuum reactive wetting and brazing of Er_(2)Si_(2)O_(7)/MoSi_(2) coatings were investigated using a (CoFeNiCrMn)_(88)Nb_(12) high-entropy alloy (HEA) brazing filler. The microstructural evolution and wettability of the HEA filler were analyzed, with particular attention to the surface energy, interfacial stability, and electronic properties of the HEA filler/rare earth silicate coating system, as determined by density functional theory (DFT). As Nb diffused into the interface and the ErNbO_(4) phase formed, the wetting angle gradually decreased to 23.12° The effective wetting and spreading of the HEA brazing filler on the rare earth silicate coating surface are strongly correlated with the formation of the ErNbO_(4) phase at the interface. Furthermore, DFT calculations reveal that the interfacial bonding energy between the BCC' and FCC' phases and the ErNbO_(4) phase, after the wetting reaction, is significantly higher than the bonding energy between the initial filler and Er_(2)Si_(2)O_(7). This finding suggests that the formation of the ErNbO_(4) phase improves the wetting and spreading behavior of the filler. 展开更多
关键词 High entropy alloy WETTABILITY Microstructures First-principles calculations Interfaces
原文传递
First-principles calculations on strain tunable hyperfine Stark shift of shallow donors in Si
11
作者 Zi-Kai Zhou Jun Kang 《Chinese Physics B》 2025年第8期413-417,共5页
Control of hyperfine interaction strength of shallow donors in Si is one of the central issues in realizing Kane quantum computers.First-principles calculations on the hyperfine Stark shift of shallow donors are chall... Control of hyperfine interaction strength of shallow donors in Si is one of the central issues in realizing Kane quantum computers.First-principles calculations on the hyperfine Stark shift of shallow donors are challenging since large supercells are needed to accommodate the delocalized donor wave functions.In this work,we investigated the hyperfine Stark shift and its strain tunability for shallow donors P and As in Si using the potential patching method based on first-principles density functional theory calculations.The good agreement between our calculations and experimental results confirms that the potential patching method is a feasible and accurate first-principles approach for studying wave-function-related properties of shallow impurities,such as the Stark shift parameter.It is further shown that the application of strain expands the range of hyperfine Stark shift and helps improve the response of shallow donor based qubit gates.The results could be useful for developing quantum computing architectures based on shallow donors in Si. 展开更多
关键词 shallow donors first-principles calculations hyperfine interaction
原文传递
Theoretical Study and Slip Effect Analysis of Elastic Calculation Methods for Steel-Concrete Composite Beams
12
作者 Shaohui Chu Xiangkai Zeng Zhixin Guo 《Journal of World Architecture》 2025年第5期67-74,共8页
Steel-concrete composite beams,due to their superior mechanical properties,are widely utilized in engineering structures.This study systematically investigates the calculation methods for internal forces and load-bear... Steel-concrete composite beams,due to their superior mechanical properties,are widely utilized in engineering structures.This study systematically investigates the calculation methods for internal forces and load-bearing capacity of composite beams based on elastic theory,with a focus on the transformed section method and its application under varying neutral axis positions.By deriving the geometric characteristics of the transformed section and incorporating a reduction factor accounting for slip effects,a computational model for sectional stress and ultimate load-bearing capacity is established.The results demonstrate that the slip effect significantly influences the flexural load-bearing capacity of composite beams.The proposed reduction factor,which considers the influence of the steel beam’s top flange thickness,offers higher accuracy compared to traditional methods.These findings provide a theoretical foundation for the design and analysis of composite beams,with significant practical engineering value. 展开更多
关键词 Composite beam Elastic calculation Slip effect Theoretical study
在线阅读 下载PDF
Accelerating multi-objective catalytic material design:A model-based method
13
作者 Baolei Li Da Wang +7 位作者 Miao Yu Chaozheng He Xue Li Jing Zhai Mdmahadi Hasan Chenxu Zhao Min Wang Dingcai Shen 《Chinese Chemical Letters》 2025年第12期363-367,共5页
Cobalt phosphide has been successfully used as a catalyst in the production of ammonia from nitric acid.Substituting appropriate atoms is expected to further improve its catalytic performance.Owing to the diversity of... Cobalt phosphide has been successfully used as a catalyst in the production of ammonia from nitric acid.Substituting appropriate atoms is expected to further improve its catalytic performance.Owing to the diversity of substituting elements,substitution sites,adsorption sites,and adsorption configurations,extensive time-consuming simulation calculations are required for the high-throughput screening method.Additionally,multi-objective attributes should be considered simultaneously in catalytic design.To tackle this challenge,this paper suggests a multi-objective cobalt phosphide catalytic material design method based on surrogate models.And the effectiveness of the proposed method was validated through comparative experiments.The proposed method led to the discovery of fifteen promising cobalt phosphide catalyst configurations.This study provides a new avenue for expediting the design of catalyst,with the potential for application in other systems. 展开更多
关键词 Surrogate model MULTI-OBJECTIVE Catalytic design Cobalt phosphide Simulation calculations
原文传递
Model-Based Decentralized Dynamic Periodic Event-Triggered Control for Nonlinear Systems Subject to Packet Losses
14
作者 Chengchao Li Xudong Zhao +2 位作者 Wei Xing Ning Xu Ning Zhao 《IEEE/CAA Journal of Automatica Sinica》 2025年第9期1908-1919,共12页
This paper studies the problem of designing a modelbased decentralized dynamic periodic event-triggering mechanism(DDPETM)for networked control systems(NCSs)subject to packet losses and external disturbances.Firstly,t... This paper studies the problem of designing a modelbased decentralized dynamic periodic event-triggering mechanism(DDPETM)for networked control systems(NCSs)subject to packet losses and external disturbances.Firstly,the entire NCSs,comprising the triggering mechanism,packet losses and output-based controller,are unified into a hybrid dynamical framework.Secondly,by introducing dynamic triggering variables,the DDPETM is designed to conserve network resources while guaranteeing desired performance properties and tolerating the maximum allowable number of successive packet losses.Thirdly,some stability conditions are derived using the Lyapunov approach.Differing from the zero-order-hold(ZOH)case,the model-based control sufficiently exploits the model information at the controller side.Between two updates,the controller predicts the plant state based on the models and received feedback information.With the model-based control,less transmission may be expected than with ZOH.Finally,numerical examples and comparative experiments demonstrate the effectiveness of the proposed method. 展开更多
关键词 Decentralized dynamic periodic event-triggering mechanism(DDPETM) hybrid system approach model-based control networked control system successive packet losses
在线阅读 下载PDF
Soil remediation potential of illite and Na-MMT for As and H_(3)AsO_(3) adsorption:Insights of ab initio calculations
15
作者 LIU Zi-rou XU Xin-hang +2 位作者 ARMAGHANI Danial Jahed SPAGNOLI Dino QI Chong-chong 《Journal of Central South University》 2025年第5期1822-1837,共16页
Understanding the adsorption behavior of heavy metals and metalloids on clay minerals is essential for remediating heavy metal-contaminated soils.The adsorption of heavy metals and metalloids on illite(001)and sodium ... Understanding the adsorption behavior of heavy metals and metalloids on clay minerals is essential for remediating heavy metal-contaminated soils.The adsorption of heavy metals and metalloids on illite(001)and sodium montmorillonite(Na-MMT)(001)surfaces was investigated using first-principles calculations in this study,especially As atom and H_(3)AsO_(3) molecule.The adsorption energies of the As atom were−1.94 eV on the illite(001)and−0.56 eV on the Na-MMT(001),whereas,the adsorption energies of the H_(3)AsO_(3) molecule were−1.40 eV on illite(001)and−1.01 eV on Na-MMT(001).The above results indicate that the adsorption was more energetically favorable on illite(001).Additionally,compared to Na-MMT(001),there were more significant interactions between the atoms/molecules on the illite(001).After As atom and H_(3)AsO_(3) molecule adsorption,the electrons were transferred from mineral surface atoms to the adsorbates on both illite(001)and Na-MMT(001)surfaces.Moreover,the adsorption of As atom on illite(001)and Na-MMT(001)surfaces were more energy favorable compared to Hg,Cd,and Cr atoms.Overall,this work provides new insights into the adsorption behavior of As atoms and As molecules on illite and Na-MMT.The results indicate that illite rich soils are more prone to contamination by arsenic compared to soils primarily composed of Na-MMT minerals. 展开更多
关键词 soil contamination clay minerals ADSORPTION ab initio calculation ARSENIC
在线阅读 下载PDF
Hazard Analysis of Dam Corridor Cracks Based on Field Detection and Numerical Calculation
16
作者 Jiacheng Li Liangkun Gong +3 位作者 Yuxiang Li Jialiang Qian Weiyu Wu Weiran Lu 《Journal of World Architecture》 2025年第1期32-39,共8页
The longitudinal cracks distributed along the dam axis in the corridor of a dam may have potential safety hazards.According to the detection results of crack depth and width and the analysis of monitoring data,a three... The longitudinal cracks distributed along the dam axis in the corridor of a dam may have potential safety hazards.According to the detection results of crack depth and width and the analysis of monitoring data,a three-dimensional finite element model is established for numerical simulation calculation and the influence of cracks on the safety of dam structure is analyzed from different aspects such as deformation,stress value,and distribution range.The calculation results show that the maximum principal tensile stress value and the location of the dam body are basically independent of the change of crack depth(within 1.0 m).Regarding local stress around the corridor,the high upstream water level causes cracks to deepen,resulting in an increase in the maximum tensile stress near the crack tip and an expansion of the tensile stress region. 展开更多
关键词 Gallery cracks Field test Finite element calculation Hazard analysis
在线阅读 下载PDF
Effect of pharmacological pupil changes on intraocular lens power calculation:a systematic review and Metaanalysis
17
作者 Si-Yi Tan Dian-Feng Liu +1 位作者 Wei-Qi Wang Bing-Song Wang 《International Journal of Ophthalmology(English edition)》 2025年第3期518-525,共8页
AIM:To investigate the effect of pharmacological pupil alterations on intraocular lens(IOL)power calculations.METHODS:A systematic review and Meta-analysis of studies published before December 2023 in the PubMed,Embas... AIM:To investigate the effect of pharmacological pupil alterations on intraocular lens(IOL)power calculations.METHODS:A systematic review and Meta-analysis of studies published before December 2023 in the PubMed,Embase,and Cochrane library databases on the accuracy of pharmacological pupil changes on IOL power calculation was performed.The primary outcome was the results of IOL power calculations before and after the use of medications.Subgroup analyses were performed based on participants’basic characteristics,such as age,axial length(AL),and whether miosis or mydriasis were used as classification criteria for further analyses.Each eligible study was evaluated for potential risk of bias by the AHRQ assessment scale.The study was registered on PROSPERO(CRD 42024497535).RESULTS:A total of 3062 eyes from 21 studies were eligible.There was no significant difference in the IOL power calculation before and after pharmacological pupil changes using any of the Hoffer Q(WMD=0.055,95%CI=-0.046–0.156;P=0.29),SRK/T(WMD=0.003,95%CI=-0.073–0.080;P=0.93),Haigis(WMD=-0.030,95%CI=-0.176–0.116;P=0.69),Holladay 2(WMD=-0.042,95%CI=-0.366–0.282;P=0.80),and Barrett Universal Ⅱ(WMD=0.033,95%CI=-0.061–0.127;P=0.49)formulas.On the measurement of parameters related to IOL power calculation,for either miosis or mydriasis AL(P=0.98 and 0.29,respectively),lens thickness(P=0.96 and 0.13,respectively),and mean keratometry(P=0.90 and 0.86,respectively)did not present significant differences,while anterior chamber depth(P=0.07 and<0.01,respectively)and white-to-white distance(P=0.01 and 0.04,respectively)changed significantly between the two measurements prior and posterior.At the same time,despite there being some participants with the difference between the before and after calculations greater than 0.5 diopter,there was no significant difference in the incidence rate between these formulas.CONCLUSION:There is no significant effect of pharmacological pupil changes on the IOL power calculation.It will considerably reduce the visit time burden for patients who require cataract surgery. 展开更多
关键词 ocular biometry intraocular lens power calculation CATARACT pharmacological pupil alterations
原文传递
Mechanism analysis of pitting induced by Al_(2)O_(3) inclusions: insight from simulation calculation
18
作者 Ting Wang Bi-jun Hua +5 位作者 Xiang-jun Liu Pei-hong Yang Xiao-xia Shi Ji-chun Yang Li Zhou Chang-qiao Yang 《Journal of Iron and Steel Research International》 2025年第4期1061-1072,共12页
The micro-area characterization experiments like scanning Kelvin probe force microscope(SKPFM)and Kernel average misorientation have the defects of complex sample preparation and occasional errors in test results,whic... The micro-area characterization experiments like scanning Kelvin probe force microscope(SKPFM)and Kernel average misorientation have the defects of complex sample preparation and occasional errors in test results,which makes it impossible to accurately and quickly analyze the pitting behavior induced by inclusions in some cases,prompting attempts to turn to simulation calculation research.The method of calculating band structure and work function can be used to replace current-sensing atomic force microscopy and SKPFM to detect the potential and conductivity of the sample.The band structure results show that Al_(2)O_(3) inclusion is an insulator and non-conductive,and it will not form galvanic corrosion with the matrix.Al_(2)O_(3) inclusion does not dissolve because its work function is higher than that of the matrix.Moreover,the stress concentration of the matrix around the inclusion can be characterized by first-principles calculation coupled with finite element simulation.The results show that the stress concentration degree of the matrix around Al_(2)O_(3) inclusion is serious,and the galvanic corrosion is formed between the high and the low stress concentration areas,which can be used to explain the reason of the pitting induced by Al_(2)O_(3) inclusions. 展开更多
关键词 PITTING Inclusion phase identification First-principles calculation Phonopy Finite element analysis
原文传递
Microstructure and mechanical properties of 6061 aluminum alloy/galvanized steel laser-arc hybrid fusion-brazed welded joint: experiment and first-principles calculation
19
作者 Hanxuan Zhang Yuchen Dong +2 位作者 Nan Li Jie Cui Liming Liu 《China Welding》 2025年第3期192-206,共15页
In this study,6061 aluminum alloy and galvanized steel fusion-brazed lap joints were obtained using a laser-arc hybrid heat source,and the effects of laser power variation on the microstructure,mechanical properties,a... In this study,6061 aluminum alloy and galvanized steel fusion-brazed lap joints were obtained using a laser-arc hybrid heat source,and the effects of laser power variation on the microstructure,mechanical properties,and fracture mechanism of the joints were ana-lyzed.The results showed that the tensile shear load initially increased with rising laser power,followed by a decrease.At a laser power of 240 W,the maximum tensile shear load was 2479.8 N/cm and the weak section of joint was in the Al-Fe reaction layer con-sisting of Fe(Al,Si)_(3),Fe_(2)(Al,Si)_(5),and Fe(Al,Si)intermetallic compounds(IMCs).Computational results showed that the inherently high brittleness and hardness of Fe(Al,Si)_(3) and the high mismatch rates of Fe(Al,Si)_(3)/Al interfaces were the key factor leading to the failure of the joints at lower heat input. 展开更多
关键词 Aluminum alloy Galvanized steel Intermetallic compounds Fracture mechanism First-principles calculation
在线阅读 下载PDF
Study of shell evolution in neutron-rich boron,carbon,and nitrogen isotopes with in-medium similarity renormalization group calculations
20
作者 Liu-Yuan Shen Qi Yuan +3 位作者 Hong-Hui Li Meng-Ran Xie Jian-Guo Li Wei Zuo 《Nuclear Science and Techniques》 2025年第11期315-325,共11页
Neutron-rich boron,carbon,and nitrogen isotopes have garnered extensive experimental and theoretical interest.In the present work,we conducted a comprehensive study of these nuclei by utilizing ab initio valence-space... Neutron-rich boron,carbon,and nitrogen isotopes have garnered extensive experimental and theoretical interest.In the present work,we conducted a comprehensive study of these nuclei by utilizing ab initio valence-space in-medium similarity renormalization group calculations with chiral nucleon-nucleon and three-nucleon interactions.First,we systematically calculated the spectra of nuclei.Our results align well with the available experimental data,which are comparable to phenomenological shell model calculations.Subsequently,the evolution of the N=14 and N=16 shell gaps is discussed based on the calculated spectra and the effective single-particle energies.Our calculations suggest that the N=14 neutron subshell is present in the oxygen isotopes but disappears in the boron,carbon,and nitrogen isotopic chains.Moreover,the N=16 subshell is present in all isotopes but gradually decreases from^(24)O to^(21)B.These results provide valuable information for future studies. 展开更多
关键词 Ab initio calculations Chiral nuclear forces Shell evolution Low-lying spectra
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部