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UC Berkeley的化工过程设计课程介绍
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作者 余立新 Fred Vorhis 《化工高等教育》 2001年第4期91-94,共4页
清华大学化学工程系正在进行课程体系调整,将化工设备设计和工艺设计两门课调整为一门课,由笔者讲授.本系教授刘铮博士1999年底在美国访问期间结识了UC Berkeley化工系的教师Fred Vorhis,对其开设的化工过程设计课程很感兴趣,并介绍给笔... 清华大学化学工程系正在进行课程体系调整,将化工设备设计和工艺设计两门课调整为一门课,由笔者讲授.本系教授刘铮博士1999年底在美国访问期间结识了UC Berkeley化工系的教师Fred Vorhis,对其开设的化工过程设计课程很感兴趣,并介绍给笔者.笔者与Fred Vorhis进行了较为广泛的交流并深入研究了其化工过程设计课程的教学大纲,发现有很多值得借鉴的地方.在征得Fred Vorhis同意后,将该门课程的教学大纲(Syllabus)的主要部分译出,并根据笔者与FredVorhis的交流讨论进行了补充,遂成此文,愿与同行切磋. 展开更多
关键词 化工过程设计课 课程目的 设计项目 考试
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ACCELERATOR-BASED ATOMIC PHYSICS AT THE LAWRENCE BERKELEY LABORATOTY:COLLISIONS OF FAST,HIGHLY-CHARGED IONS WITH ATOMS
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作者 AlfredS.Schlachter 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第Z1期32-39,共8页
Research on accelerator-based atomic physics at the Lawrence Berkeley Laboratory super-HILAC and Bevalac accelerators is described. This research covers several important topics in collisions of fast, highly charged i... Research on accelerator-based atomic physics at the Lawrence Berkeley Laboratory super-HILAC and Bevalac accelerators is described. This research covers several important topics in collisions of fast, highly charged ions with atoms: charge transfer, ionization, and excitation. Multiple - electron processes are emphasized. Electron correlation is important in some of these processes, e.g., resonance transfer and excitation (RTE) multiple-electron capture in close collisions. A variety of experiments and results for energies from 1 to 420 MeV/u are presented. 展开更多
关键词 ACCELERATOR ATOMIC physics COLLISIONS of IONS with ATOMS
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The need to consider regional supply chains and water usage in H_(2)–steel transition
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作者 Peng Peng Tae Lim +3 位作者 Fabian Rosner Hanna Breunig Prakash Rao Arman Shehabi 《Green Energy & Environment》 2026年第1期23-35,共13页
The iron and steel industry is one of the largest contributors to U.S.and global greenhouse gas emissions.Hydrogen can act as a promising reducing agent and clean energy carrier to decarbonize this sector,and has rece... The iron and steel industry is one of the largest contributors to U.S.and global greenhouse gas emissions.Hydrogen can act as a promising reducing agent and clean energy carrier to decarbonize this sector,and has received significant attention in terms of process modelling,techno-economic analysis,and life cycle assessment in recent years.Policy incentives,hydrogen storage and transportation,and water stress levels are key factors that require significantly more consideration in order to realize hydrogen's potential to decarbonize this industry.This review demonstrates the need for a systematic understanding and critical assessment of these areas,and their profound impacts on the decarbonization of the iron and steel sector.Furthermore,hydrogen and water supply face competition from other hard-to-decarbonize sectors,which should be considered on national and regional levels.Lastly,future research should also consider the impact of other environmental factors and hydrogen leak when deploying hydrogen at scale for industrial decarbonization. 展开更多
关键词 Iron and steel Green steel Hydrogen Industrial decarbonization Water stress level
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Multiphysics modeling of thermo-hydraulic fracturing during CO_(2)sequestration in multilayered reservoirs at Ordos,China
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作者 Yi Li Yinjiang Liu +2 位作者 Quanlin Zhou Hao Yu Bin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1233-1249,共17页
The increase in CO_(2)injectivity and shifting of CO_(2)-absorbing layers in multilayered geological CO_(2)sequestration(GCS)reservoirs in Ordos,China indicate significantpermeability variations in certain layers.To c... The increase in CO_(2)injectivity and shifting of CO_(2)-absorbing layers in multilayered geological CO_(2)sequestration(GCS)reservoirs in Ordos,China indicate significantpermeability variations in certain layers.To capture these system changes,a numerical model incorporating all 21 aquifers and internal aquitards was developed.The monitored pressure was well matched through multiphase and thermalhydraulic-mechanical(THM)coupling numerical simulations by introducing permeability variations.The results revealed that the permeability in the second layer increased on approximately day 13 due to the abrupt pressure buildup and temperature decrease.Even such a low rate of CO_(2)(2.8 kg/s)injected into the low permeability system initiated some fractures and the permeability in the second layer around the wellbore increased by 722 times.The second critical system change occurred on approximately day 386.As demonstrated in the numerical simulation,the substantial injection of cold CO_(2)induced strong thermal stress,leading to rock contraction and the initiation of several cracks.The permeability of the firstlayer around the wellbore unexpectedly increased by 4 orders of magnitude.Since no additional pressure could drive the CO_(2)into the remaining 17 layers,the total storage capability of the multilayered system was reduced.A whole picture of the system variation is fully presented and the underlying mechanisms are analyzed.It is believed that the phenomenon of thermal-hydraulic fracturing observed in this fieldand the simulation procedures will benefitother fluidinjection and production works in various geotechnical settings. 展开更多
关键词 Geological CO_(2)sequestration(GCS) Thermal-hydraulic-mechanical(THM) couplings Thermal-hydraulic fracturing Monitoring analysis Fracture flow Field data
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分段进水SBR工艺处理高负荷城镇污水 被引量:2
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作者 郭钟锐 孙滢斐 付根深 《环境科学与技术》 北大核心 2025年第1期101-107,共7页
该文以某SBR工艺的城镇污水处理厂为研究对象,探讨了分段进水的工艺优化及自控系统的升级改造。结果表明,采用分段进水能有效解决高负荷城镇污水中氨氮降解迟滞的问题,减污降碳效果显著。在全流程分析中,分段等量进水相比于正常进水,其... 该文以某SBR工艺的城镇污水处理厂为研究对象,探讨了分段进水的工艺优化及自控系统的升级改造。结果表明,采用分段进水能有效解决高负荷城镇污水中氨氮降解迟滞的问题,减污降碳效果显著。在全流程分析中,分段等量进水相比于正常进水,其含氮污染物减少了41.9%。在实际运行过程中,出水水质得到进一步改善,处理水量及出水稳定性显著提高,处理水量同比增加12.0%,总氮去除率由88.2%提升至91.3%,COD污染物削减量增加1 061 t,同比提高24.3%。此外,分段进水在节能方面表现出显著优势,综合电单耗为0.427 kW·h/m^(3),同比降低5.32%;生产药剂中的碳源单耗减少13.28%,除磷药剂单耗降低8.97%。 展开更多
关键词 分段进水 高负荷城镇污水 减污降碳 节能降耗
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Intelligent Design Method for Thermal Conductivity Topology Based on a Deep Generative Network 被引量:1
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作者 Qiyin Lin Feiyu Gu +5 位作者 Chen Wang Hao Guan Tao Wang Kaiyi Zhou Lian Liu Desheng Yao 《Chinese Journal of Mechanical Engineering》 2025年第6期67-82,共16页
Heat dissipation performance is critical to the design of high-end equipment,such as integrated chips and high-precision machine tools.Owing to the advantages of artificial intelligence in solving complex tasks involv... Heat dissipation performance is critical to the design of high-end equipment,such as integrated chips and high-precision machine tools.Owing to the advantages of artificial intelligence in solving complex tasks involving a large number of variables,researchers have exploited deep learning to expedite the optimization of material properties,such as the heat dissipation of solid isotropic materials with penalization(SIMP).However,because the approach is limited by discrete datasets and labeled training forms,ensuring the continuous adaptation of the condition domain and maintaining the stability of the design structure remain major challenges in the current intelligent design methodology for thermally conductive structures.In this study,we propose an innovative intelligent design fram-ework integrating Conditional Deep Convolutional Generative Adversarial Networks(CDCGAN)with SIMP,capable of creating topology structures that meet prescribed thermal conduction performance.This proposed design strategy significantly reduces the computational time required to solve symmetric and random heat sink problems compared with existing design approaches and is approximately 98%faster than standard SIMP methods and 55.5%faster than conventional deep-learning-based methods.In addition,we benchmarked the design performance of the proposed framework against theoretical structural designs via experimental measurements.We observed a 50.1%reduction in the average temperature and a 28.2%reduction in the highest temperature in our designed topology compared with those theoretical structure designs. 展开更多
关键词 Topology optimization Intelligent prediction Thermal conductivity structure Generative adversarial network Instantaneous prediction
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Emerging multifaceted roles of the microbiome in cancer susceptibility 被引量:1
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作者 Hang Chang Jesus Perez-Losada Jian-Hua Mao 《World Journal of Clinical Oncology》 2025年第9期92-105,共14页
Identifying the factors that contribute to individual susceptibility to cancer is essential for both prevention and treatment.The advancement of biotechnologies,particularly next-generation sequencing,has accelerated ... Identifying the factors that contribute to individual susceptibility to cancer is essential for both prevention and treatment.The advancement of biotechnologies,particularly next-generation sequencing,has accelerated the discovery of genetic variants linked to cancer susceptibility.While hundreds of cancer-susceptibility genes have been identified,they only explain a small fraction of the overall cancer risk,a phenomenon known as"missing heritability".Despite progress,even considering factors such as epistasis,epigenetics,and gene-environment interactions,the missing heritability remains unresolved.Recent research has revealed that an individual's microbiome composition plays a significant role in cancer susceptibility through several mechanisms,such as modulating immune cell activity and influencing the presence or removal of environmental carcinogens.In this review,we examine the multifaceted roles of the microbiome in cancer risk and explore gene-microbiome and environment-microbiome interactions that may contribute to cancer susceptibility.Additionally,we highlight the importance of experimental models,such as collaborative cross mice,and advanced analytical tools,like artificial intelligence,in identifying microbial factors associated with cancer risk.Understanding these microbial determinants can open new avenues for interventions aimed at reducing cancer risk and guide the development of more effective cancer treatments. 展开更多
关键词 Cancer susceptibility Genetic variants Genome-wide association study Missing heritability MICROBIOME Microbiome-wide association study
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Combining machine learning algorithms with traditional methods for resolving the atomic-scale dynamic structure of monolayer MoS_(2) in high-resolution transmission electron microscopy 被引量:1
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作者 Yu Meng Shuya Wang +5 位作者 Xibiao Ren Han Xue Xuejun Yue Chuanhong Jin Shanggang Lin Fang Lin 《Chinese Physics B》 2025年第1期162-170,共9页
High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-co... High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-corrected transmission electron microscopy constrain resolution.A machine learning algorithm is developed to determine the aberration parameters with higher precision from small,lattice-periodic crystal images.The proposed algorithm is then validated with simulated HRTEM images of graphene and applied to the experimental images of a molybdenum disulfide(MoS_(2))monolayer with 25 variables(14 aberrations)resolved in wide ranges.Using these measured parameters,the phases of the exit-wave functions are reconstructed for each image in a focal series of MoS_(2)monolayers.The images were acquired due to the unexpected movement of the specimen holder.Four-dimensional data extraction reveals time-varying atomic structures and ripple.In particular,the atomic evolution of the sulfur-vacancy point and line defects,as well as the edge structure near the amorphous,is visualized as the resolution has been improved from about 1.75?to 0.9 A.This method can help salvage important transmission electron microscope images and is beneficial for the images obtained from electron microscopes with average stability. 展开更多
关键词 aberration measurement high-resolution transmission electron microscopy feature-extraction networks exit-wave reconstruction monolayer MoS_(2)
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Eco-functional divergence of Crocuta and Pachycrocuta:a Huainan specimen reappraisal
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作者 LIU Jin-Yi Zhijie Jack TSENG +3 位作者 JIN Chang-Zhu ZHENG Long-Ting SUN Cheng-Kai TONG Hao-Wen 《古脊椎动物学报(中英文)》 北大核心 2025年第4期277-322,共46页
Crocuta and Pachycrocuta are widely regarded as the most prevalent and emblematic hyenas across Eurasia during Quaternary.They are easily distinguished by their distinctive carnassial teeth.However,the disparities in ... Crocuta and Pachycrocuta are widely regarded as the most prevalent and emblematic hyenas across Eurasia during Quaternary.They are easily distinguished by their distinctive carnassial teeth.However,the disparities in non-carnassial elements are less pronounced and have received minimal attention in previous studies.This has resulted in erroneous identifications when dealing with fragmented specimens,particularly in cases where carnassial teeth are poorly preserved or absent.Such misidentifications have the potential to give rise to erroneous inferences regarding the paleozoogeography and biochronology of the animals in question.The bone-cracking hyena specimens from Huainan,Anhui(Tseng et al.,2008)are re-examined and re-evaluated here through a series of morphological comparisons and data analyses(univariate,bivariate,and multivariate analyses etc.).The results provide unequivocal confirmation that the specimens from Xiliexi are not spotted hyenas,but belong to Pachycrocuta perrieri instead.Conversely,the specimen from Dadingshan is the only genuine representative of the spotted hyena,which is supposed to be a possible earliest fossil record for Crocuta ultima thus far in China.Furthermore,the disparities in dentognathic morphology between Crocuta and Pachycrocuta are systematically summarized and analyzed,with an explanation of their eco-functional significance.The present study hypothesizes that Pachycrocuta retains a certain degree of active predatory capability,attributable to the robustness of the canine and the symphysis of the jaw,among other factors.This finding indicates that Pachycrocuta exhibits a form of flexible foraging behavior,combining opportunistic scavenging and active hunting in a manner analogous to Crocuta.Finally,the dynamic evolutionary history of hyenas in East China since Pleistocene has also been broadly reconstructed. 展开更多
关键词 Huainan Anhui PLEISTOCENE re-examination Pachycrocuta perrieri Crocuta honanensis Crocuta ultima morphological comparison statistical analysis
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Late Miocene immigrant carnivorans in California,USA highlight a coastal corridor for intercontinental dispersals
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作者 Zhijie Jack TSENG WANG Xiao-Ming 《古脊椎动物学报(中英文)》 北大核心 2025年第4期266-276,共11页
The Neogene interval witnessed three major waves of intercontinental dispersals by carnivoran mammals,mainly migrating from Eurasia to North America but with rare occurrences going in the opposite direction(e.g.,Sthen... The Neogene interval witnessed three major waves of intercontinental dispersals by carnivoran mammals,mainly migrating from Eurasia to North America but with rare occurrences going in the opposite direction(e.g.,Sthenictis,Leptarctus).The timing and composition of dispersers are thought to be controlled by filter-bridge mechanisms,but it is unclear what types of regional conditions promoted occasional dispersals outside of the three major waves.We study and report on new occurrences of small-bodied carnivorans from late Clarendonian-aged Black Hawk Ranch and Cuyama Valley fossil mammal assemblages in California.The relatively late occurrences of the mustelids Sthenictis and Hoplictis and the ailurid Alopecocyon in coastal regions of western North America suggest that nearshore dispersal corridors both facilitate and preserve faunal elements later than they might otherwise occur further inland.The availability of both marine-and terrestrially-derived food resources may be an important factor in allowing coastally dispersing taxa to be accommodated in those ecological communities compared to less heterogenous environments further inland. 展开更多
关键词 California CENOZOIC PALEOBIOGEOGRAPHY MAMMALS CARNIVORA
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A perspective on design principle of solid electrolytes
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作者 Yingzhi Sun 《Journal of Energy Chemistry》 2025年第6期570-576,I0013,共8页
1.Introduction.The ever-increasing demands for high-energy-density power supply systems have driven the rapid development of conventional lithium-ion batteries,of which properties are approaching to the ceiling.In the... 1.Introduction.The ever-increasing demands for high-energy-density power supply systems have driven the rapid development of conventional lithium-ion batteries,of which properties are approaching to the ceiling.In the meantime,the safety of lithium-ion batteries also grabs more attention as their wide application in consumer electronics and electric vehicles.The safety of battery system can be enhanced inherently by replacing the flammable liquid electrolytes with inorganic solid electrolytes,which makes solid-state battery one of the most promising candidates of next-generation energy storage systems[1-3].Additionally,the improvements in energy density are foreseen as solid electrolytes enable lithium metal anode[4-11]and high-voltage cathodes[12-15]. 展开更多
关键词 inorganic solid electrolyteswhich electric vehiclesthe consumer electronics battery system flammable liquid electrolytes SAFETY lithium ion batteries solid electrolytes
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Evaluating indoor thermal resilience of passive and low-power cooling shelters for outdoor workers in India
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作者 Yi Wu Jeetika Malik +4 位作者 Tianzhen Hong Elif Kilic Prasad Vaidya Da Yan Ashok Gadgil 《Building Simulation》 2025年第12期3373-3391,共19页
India’s 231 million outdoor workers are exposed to deadly heat during heat waves.We report results from a simulation-based study that focuses on passive design of cooling shelters for the hot and dry climate zone of ... India’s 231 million outdoor workers are exposed to deadly heat during heat waves.We report results from a simulation-based study that focuses on passive design of cooling shelters for the hot and dry climate zone of India.The goal is to design a cooler-than-outdoor shelter for outdoor workers’intermittent rest and recovery from heat stress during their arduous outdoor work,to avoid heat-related morbidities and mortality.Expected indoor thermal conditions in low-cost cooling shelters deploying a range of passive designs and low-power active measures are investigated,consistent with the current Indian standards and practices,located in the city of Jodhpur in western India.Heat resilience of the shelter was measured with the predicted reduction of hazardous hours inside the shelter based on the wet-bulb globe temperature(WBGT)and extended heat index.These measures include improving the building envelope,installing cool roofs,using internal thermal mass,and natural ventilation.Additionally,a low-power active measure of using ventilation fans and ceiling fans is explored.EnergyPlus-based simulation results show that simple,commonly available measures,particularly natural ventilation and ceiling fans,achieve the most significant reductions in overheating danger hours,by 22% and 21%,respectively,while more complex or costly passive strategies yield only marginal additional benefits.Moreover,combined measure packages are identified that can reduce the indoor WBGT by 8 to 10℃,eliminating overheating danger hours.These findings highlight the critical importance of scalable,low-cost,and easily deployable cooling solutions for developing resilient cooling shelters for vulnerable outdoor workers during heat waves in India. 展开更多
关键词 cooling shelter building performance simulation thermal resilience outdoor worker heat waves
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Numerical simulation of coupled thermal-hydro-mechanical processes in geologic nuclear waste disposal with corrosion-induced gas generation
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作者 Tianjia Huang Jonny Rutqvist +1 位作者 George J.Moridis Thomas A.Blasingame 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期6767-6786,共20页
An important challenge in ensuring the long-term effectiveness of geological nuclear waste disposal is predicting the transportation of decay heat and gases released from nuclear waste canisters.In this study,thermo-h... An important challenge in ensuring the long-term effectiveness of geological nuclear waste disposal is predicting the transportation of decay heat and gases released from nuclear waste canisters.In this study,thermo-hydromechanical(THM)coupled simulations were conducted using the TOUGH + FLAC3D simulator to predict the THM behaviors of a generic nuclear waste repository over 100,000 years following closure.The designed engineered barrier system(EBS)consists of the waste canister,backfill,and concrete liner.The objective of this study is to evaluate the long-term performance of the repository in the presence of continued hydrogen(H_(2))and heat release around the canister.The simulation results show that thermal pressurization and gas accumulation significantly raise the pore pressure within the EBS and surrounding host rock,while the peak pore pressure is not likely to exceed the lithostatic stress so that there is no risk of widespread hydro-fracturing in the host rock.However,tension failure and fracturing can occur at the tunnel scale because of internal gas buildup.Meanwhile,the generated H_(2) continuously migrates outward and tends to accumulate in the concrete liner and excavation disturbed zone surrounding the tunnel because of lower capillary pressure.Nevertheless,the fluids that may contain radionuclides will not leach into the confining units over a 100,000-year time frame.Our analysis indicates that for the assumed disposal system in Opalinus Clay,the generated heat and gas can gradually be transported through the host rock without significantly disturbing the isolation characteristics of the repository. 展开更多
关键词 Nuclear waste disposal Coupled thermo-hydromechanical modeling Gas generation and transportation Multiphase flow
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Stochastic state of health estimation for lithium-ion batteries with automated feature fusion using quantum convolutional neural network
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作者 Chen Liang Shengyu Tao +3 位作者 Xinghao Huang Yezhen Wang Bizhong Xia Xuan Zhang 《Journal of Energy Chemistry》 2025年第7期205-219,共15页
The accurate state of health(SOH)estimation of lithium-ion batteries is crucial for efficient,healthy,and safe operation of battery systems.Extracting meaningful aging information from highly stochastic and noisy data... The accurate state of health(SOH)estimation of lithium-ion batteries is crucial for efficient,healthy,and safe operation of battery systems.Extracting meaningful aging information from highly stochastic and noisy data segments while designing SOH estimation algorithms that efficiently handle the large-scale computational demands of cloud-based battery management systems presents a substantial challenge.In this work,we propose a quantum convolutional neural network(QCNN)model designed for accurate,robust,and generalizable SOH estimation with minimal data and parameter requirements and is compatible with quantum computing cloud platforms in the Noisy Intermediate-Scale Quantum.First,we utilize data from 4 datasets comprising 272 cells,covering 5 chemical compositions,4 rated parameters,and 73operating conditions.We design 5 voltage windows as small as 0.3 V for each cell from incremental capacity peaks for stochastic SOH estimation scenarios generation.We extract 3 effective health indicators(HIs)sequences and develop an automated feature fusion method using quantum rotation gate encoding,achieving an R2of 96%.Subsequently,we design a QCNN whose convolutional layer,constructed with variational quantum circuits,comprises merely 39 parameters.Additionally,we explore the impact of training set size,using strategies,and battery materials on the model’s accuracy.Finally,the QCNN with quantum convolutional layers reduces root mean squared error by 28% and achieves an R^(2)exceeding 96% compared to other three commonly used algorithms.This work demonstrates the effectiveness of quantum encoding for automated feature fusion of HIs extracted from limited discharge data.It highlights the potential of QCNN in improving the accuracy,robustness,and generalization of SOH estimation while dealing with stochastic and noisy data with few parameters and simple structure.It also suggests a new paradigm for leveraging quantum computational power in SOH estimation. 展开更多
关键词 Lithium-ion battery State of health Feature fusion Quantum convolutional neural network Quantum machine learning
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Analysis of the Minute Differences between the Internal Structures of Green-Emitting Quantum Dots Via Synchrotron-Based X-Ray Photoelectron Spectroscopy
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作者 Dong-Jin Yun Nayoun Won +10 位作者 Young Mo Sung Tae-Gon Kim Taekhoon Kim Ane Etxebarria Kyungjae Lee SooHwan Sul Hyokeun Park SungJun Park Jung-Hwa Kim Shinae Jun Ethan Crumlin 《Energy & Environmental Materials》 2025年第1期313-322,共10页
The development of an analytical method for determining the properties of quantum dots(QDs)is crucial for improving the optical performance of QD-based displays.Therefore,synchrotron-based X-ray photoelectron spectros... The development of an analytical method for determining the properties of quantum dots(QDs)is crucial for improving the optical performance of QD-based displays.Therefore,synchrotron-based X-ray photoelectron spectroscopy(XPS)is designed here to accurately characterize the chemical and structural differences between different QDs.This method enables the determination of the reason for the minimal differences between the optical properties of different QDs depending on the synthesis process,which is difficult to determine using conventional methods alone.Combined with model simulations,the XPS spectra obtained at different photon energies reveal the internal structures and chemical-state distributions of the QDs.In particular,the QD synthesized under optimal conditions demonstrates a relatively lower degree of oxidation of the core and more uniformly stacked ZnSe/ZnS shell layers.The internal structures and chemical-state distributions of QDs are closely related to their optical properties.Finally,the synchrotron-based XPS proposed here can be applied to compare nearly equivalent QDs with slightly different optical properties. 展开更多
关键词 chemical state indium phosphide-based quantum dot inelastic mean free path internal structure synchrotron-based X-ray photoelectron spectroscopy
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Corticosteroids in posterior reversible encephalopathy syndrome:Friend or foe?A systematic review
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作者 Bahadar S Srichawla Taranjit Kaur Harsimran Singh 《World Journal of Clinical Cases》 2025年第12期22-47,共26页
BACKGROUND Posterior reversible encephalopathy syndrome(PRES)is a complex neurological disorder characterized by symptoms such as headaches,seizures,confusion,and visual disturbances.The pathophysiology of PRES involv... BACKGROUND Posterior reversible encephalopathy syndrome(PRES)is a complex neurological disorder characterized by symptoms such as headaches,seizures,confusion,and visual disturbances.The pathophysiology of PRES involves endothelial dysfunction,disrupted cerebral autoregulation,and resulting vasogenic edema.Hypertension and other factors that alter cerebral autoregulation are critical in its development.Corticosteroids,widely used for their anti-inflammatory and immunosuppressive properties,play a controversial role in PRES.AIM To elucidate the dual role of corticosteroids in the context of PRES by critically evaluating the existing literature.Specifically,it seeks to assess the results of PRES induced by corticosteroid therapy and the efficacy and safety of corticosteroids in the treatment of PRES.By synthesizing case reports and series,this review aims to provide a comprehensive understanding of the mechanisms,clinical presentations,and management strategies associated with corticosteroid-related PRES.METHODS The review was carried out according to the PRISMA guidelines.The databases searched included Science Direct,PubMed,and Hinari.The search strategy encompassed terms related to corticosteroids and PRES.Studies were included if they were peer-reviewed articles examining corticosteroids in PRES,excluding non-English publications,reviews,and editorials.Data on patient demographics,clinical characteristics,imaging findings,corticosteroid regimens,and outcomes were extracted.The risk of bias was evaluated using the Joanna Briggs Institute tool for case reports.RESULTS A total of 56 cases of PRES(66.1%women,33.9%men)potentially induced by corticosteroids and 14 cases in which corticosteroids were used to treat PRES were identified.Cases of PRES reportedly caused by corticosteroids showed a mean age of approximately 25.2 years,with seizures,headaches,hypertension,and visual disturbances being common clinical sequelae.Magnetic resonance findings typically revealed vasogenic edema in the bilateral parieto-occipital lobes.High-dose or prolonged corticosteroid therapy was a significant risk factor.On the contrary,in the treatment cases,corticosteroids were associated with positive outcomes,including resolution of vasogenic edema and stabilization of symptoms,particularly in patients with underlying inflammatory or autoimmune diseases.CONCLUSION Corticosteroids have a dual role in PRES,capable of both inducing and treating the condition.The current body of literature suggests that corticosteroids may play a greater role as a precipitating agent of PRES rather than treating.Corticosteroids may induce PRES through hypertension and subsequent increased cerebral blood flow and loss of autoregulation.Corticosteroids may aid in the management of PRES:(1)Enhancing endothelial stability;(2)Antiinflammatory properties;and(3)Improving blood-brain barrier integrity.Mechanisms which may reduce or mitigate vasogenic edema formation. 展开更多
关键词 CORTICOSTEROIDS Posterior reversible encephalopathy syndrome Vasogenic edema Reversible posterior leukoencephalopathy syndrome Reversible cerebral vasoconstriction syndrome
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Choroidal response to optical defocus as a potential surrogate marker for myopia control effect
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作者 Muteb K.Alanazi Mohammed Alshehri +7 位作者 Mohammed Althomali Mohammed Alhazmi Mansour Alghamdi Nawaf M.Almutairi Basal Altoaimi Ahmed Alharbi Ali Almustanyir Maria Liu 《International Journal of Ophthalmology(English edition)》 2025年第8期1529-1536,共8页
AIM:To investigate short-term changes in choroidal thickness in response to peripheral myopic defocus induced by two designs of multifocal corneal gas permeable contact lenses(MFGPCL)in young adults.METHODS:Seventeen ... AIM:To investigate short-term changes in choroidal thickness in response to peripheral myopic defocus induced by two designs of multifocal corneal gas permeable contact lenses(MFGPCL)in young adults.METHODS:Seventeen participants,with a mean age of 24.5±4y,underwent choroidal thickness and vascularity index measurements using enhanced depth imaging optical coherence tomography(EDI OCT)at baseline,one day,and one week following MFGPCL wear.Two center-distance MFGPCL designs with similar center zone diameters of 3.0 mm but different peripheral add powers(low add:+1.5 D and high add:+3.0 D)were tested.Each participant was randomly assigned to wear one of the two MFGPCL designs.Measurements of total,luminal,and stromal choroid thickness were obtained in five eccentric regions(6 mm towards the periphery)in all quadrants.RESULTS:Significant thickening in total choroidal thickness were observed after one week of wearing both high add(+10±6µm)and low add(+7±5µm)MFGPCLs,with no statistically significant difference between the two groups(P=0.42).Choroidal thickening was consistent across eccentric regions and quadrants,with no significant differences based on eccentricity or quadrant(all P>0.05).Both lens designs induced choroidal thickening,with no significant difference between them in total choroidal thickness(P=0.18 for quadrants,P=0.51 for eccentric regions).CONCLUSION:Peripheral myopic defocus induced by MFGPCLs lead to significant choroidal thickening,including total,luminal,and stromal components.This study highlights the need for future research to explore the dose-response relationship between peripheral myopic defocus and choroidal thickening,utilizing choroidal response as a potential biomarker. 展开更多
关键词 CHOROID choroidal vascularity index gas-permeable contact lens MYOPIA
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Association Between Long-Term PM1 Exposure and Cognitionin Middle-Aged and Older Adults:Evidence from China and the United Kingdom
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作者 Qiurun Yu Hongcheng Wei +7 位作者 Mingzhi Zhang Xiaochen Zhang Francis Manyori Bigambo Danrong Chen Quanquan Guan Bo Hang Antoine M.Snijders Yankai Xia 《Engineering》 2025年第10期223-230,共8页
Early risk detection and management are essential for cognitive preservation.While particulate matter with a diameter smaller than 2.5μm(PM_(2.5))is considered harmful to cognition,the effect of smaller,more penetrat... Early risk detection and management are essential for cognitive preservation.While particulate matter with a diameter smaller than 2.5μm(PM_(2.5))is considered harmful to cognition,the effect of smaller,more penetrative particulate matter with a diameter smaller than 1μm(PM_(1))requires further evidence and explicit safety thresholds.In this study,we explored the effects of long-term PM_(1) exposure on early cognitive impairment and longitudinal cognitive changes in middle-aged and older populations.This study assessed data from two large-scale longitudinal surveys:the China Health and Retirement Longitudinal Study(CHARLS)and UK Biobank(UKB).Cross-sectional,longitudinal,and trajectory analyses were conducted to investigate the association between long-term PM_(1) exposure and cognition.Additionally,the expo sure-response curves were fitted to determine the customized thresholds.The findings indicated that sustained PM_(1) exposure may lead to mild cognitive impairment,particularly at concentrations exceeding 30 and 5.6μg·m^(-3) in CHARLS and UKB participants,respectively.Furthermore,we found that long-term PM_(1) exposure can contribute to rapid cognitive decline at concentrations exceeding 23 and 5.5μg·m^(-3) in CHARLS and UKB participants,respectively.In conclusion,reducing PM_(1) exposure can improve the cognitive health of middle-aged and older adults. 展开更多
关键词 PM_(1) COGNITION Mild cognitiveimpairment Rapid cognitivedecline Longitudinal study Multi-regional study
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High-resolution Photoelectron Spectroscopy of Cryogenically Cooled TiO_(2)CH_(3)OH^(−):An Investigation of Methanol Splitting by TiO_(2)^(−/0)
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作者 Korina Vlahos Martin DeWitt Daniel M.Neumark 《Chinese Journal of Chemical Physics》 2025年第6期750-760,I0002-I0010,I0237,共21页
High-resolution photoelectron spectra of cryogenically cooled TiO_(2)CH_(3)OH^(−)anions obtained with slow electron velocity-map imaging are reported and used to explore the reactions of TiO_(2)^(−/0)with methanol.The... High-resolution photoelectron spectra of cryogenically cooled TiO_(2)CH_(3)OH^(−)anions obtained with slow electron velocity-map imaging are reported and used to explore the reactions of TiO_(2)^(−/0)with methanol.The highly structured spectra were compared with results from DFT calculations to determine the dominant structure to be cis-CH_(3)OTi(O)OH^(−),a dissociative adduct in which CH3OH is split by TiO_(2)^(−).The experiment yields an electron affinity of 1.2152(7)eV for TiO_(2)CH^(3)OH as well as several vibrational frequencies for the neutral species.Comparison to Franck−Condon(FC)simulations shows that while most experimental features appear in the simulations,several are not and are assigned to FC-forbidden transitions involving non-totally symmetric vibrational modes.The FC-allowed and forbidden transi-tions also exhibit different photoelectron angular distributions.The FC-forbidden transitions are attributed to Herzberg−Teller(HT)coupling with the A^(2)A″excited state of the anion.The results are compared to previous cryogenic slow electron velocity-map imaging(cryo-SE-Ⅵ)studies of bare TiO_(2)^(−)and the water-split adduct TiO_(3)H_(2)^(−). 展开更多
关键词 Photoelectron spectroscopy Cryogenically cooled clusters TITANIA Methanol splitting
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Dimethoxymethane carbonylation and disproportionation over extra-large pore zeolite ZEO-1:Reaction network and mechanism
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作者 Shaolei Gao Peng Lu +6 位作者 Liang Qi Yingli Wang Hua Li Mao Ye Valentin Valtchev Alexis T.Bell Zhongmin Liu 《Chinese Journal of Catalysis》 2025年第1期230-245,共16页
Methyl methoxyacetate(MMAc)and methyl formate(MF)can be produced directly by heterogeneous zeolite-catalyzed carbonylation and disproportionation of dimethoxymethane(DMM),with near 100%selectivity for each process.Des... Methyl methoxyacetate(MMAc)and methyl formate(MF)can be produced directly by heterogeneous zeolite-catalyzed carbonylation and disproportionation of dimethoxymethane(DMM),with near 100%selectivity for each process.Despite continuous research efforts,the insight into the reaction mechanism and kinetics theory are still in their nascent stage.In this study,ZEO-1 material,a zeolite with up to now the largest cages comprising 16×16-MRs,16×12-MRs,and 12×12-MRs,was explored for DMM carbonylation and disproportionation reactions.The rate of MMAc formation based on accessible Brönsted acid sites is 2.5 times higher for ZEO-1(Si/Al=21)relative to the previously investigated FAU(Si/Al=15),indicating the positive effect of spatial separation of active sites in ZEO-1 on catalytic activity.A higher MF formation rate is also observed over ZEO-1 with lower activation energy(79.94 vs.95.19 kJ/mol)compared with FAU(Si/Al=30).Two types of active sites are proposed within ZEO-1 zeolite:Site 1 located in large cages formed by 16×16-MRs and 16×12-MRs,which is active predominantly for MMAc formation,and Site 2 located in smaller cages for methyl formate/dimethyl ether formation.Kinetics investigation of DMM carbonylation over ZEO-1 exhibit a first-order dependence on CO partial pressure and a slightly inverse-order dependence on DMM partial pressure.The DMM disproportionation is nearly first-order dependence on DMM partial pressure,while it reveals a strongly inverse dependence with increasing CO partial pressure.Furthermore,ZEO-1 exhibits good catalytic stability,and almost no deactivation is observed during the more than 70 h test with high carbonylation selectivity of above 89%,due to the well-enhanced diffusion property demonstrated by intelligent-gravimetric analysis. 展开更多
关键词 Dimethoxymethane carbonylation Dimethoxymethane disproportionation ZEOLITE In-situ IR Kinetic Reaction mechanism
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