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Real-time monitoring of oxygenation in deep brain tissue using a wireless photoelectric probe

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Science China Materials 2024年第4期67卷 1361-1362页

作者： hao Pang Qilin Hua Guozhen Shen School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100084China Institute of Flexible Electronics Beijing Institute of TechnologyBeijing 102488China

Oxygen(O2) supply to the brain is of utmost importance for human health, as cerebral hypoxia can result in irreversible brain damage. Neurodegenerative diseases, such as epilepsy, are closely associated with cerebral hypoxia [1,2]. Real-time monitoring of cerebral oxygenation holds significant value in neuroscience research and clinical diagnostics [3–10].

关键词： epilepsy cerebral diseases

A High Order Accurate Bound-Preserving Compact Finite Difference Scheme for Two-Dimensional Incompressible Flow

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Communications on Applied Mathematics and Computation 2024年第1期6卷 113-141页

作者： hao Li Xiangxiong Zhang Department of Mathematics Purdue University150 N.University StreetWest LafayetteIN47907-2067USA

For solving two-dimensional incompressible flow in the vorticity form by the fourth-order compact finite difference scheme and explicit strong stability preserving temporal discretizations,we show that the simple bound-preserving limiter in Li et al.(SIAM J Numer Anal 56:3308–3345,2018)can enforce the strict bounds of the vorticity,if the velocity field satisfies a discrete divergence free *** reducing oscillations,a modified TVB limiter adapted from Cockburn and Shu(SIAM J Numer Anal 31:607–627,1994)is constructed without affecting the bound-preserving *** bound-preserving finite difference method can be used for any passive convection equation with a divergence free velocity field.

关键词： Finite difference Monotonicity Bound-preserving Discrete maximum principle Passive convection Incompressible flow Total variation bounded limiter

Toxicity mechanisms of photodegraded polyvinyl chloride nanoplastics on pea seedlings

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 111-124页

作者： hao Wu Beibei He Bocheng Chen An Liu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Nanoplasctics(NPs),which are very small in particle size,exert toxic effect to ***,compared to original NPs,photodegraded NPs would pose higher *** is because their relatively higher specific surface areas and the presence of additives which can more easily *** original NPs and aged NPs affect plant growth has not been widely *** work chose polyvinyl chloride NPs(PVC-NPs)that were subjected to up to 1000 h UV light radiation to explore the impact of PVC-NPs on the growth of pea seedlings(Pisum Sativum L.).The results indicated the existence of PVC-NPs with longer UV light radiation time and higher concentrations had more negative influences on pea seedlings’growth such as germination rate(decreased by 10.6%–22.5%),stem length(decreased by 2.8%–8.1%),dry weight(decreased by 6.3%–7.1%)and fresh weight(decreased by 6.7%–14.8%).It was also noted that photodegraded PVC-NPs resulted in damage to leaf stomata and roots,hindering photosynthesis and absorption of nutrients and hence the decrease in chlorophyll and soluble sugar *** to transcriptomic investigation results,the presence of aged PVC-NPs primarily influenced protein processing in endoplasmic reticulum(upregulated metabolic pathway)and phenylpropanoid biosynthesis(downregulated metabolic pathway)of pea *** results provide an in-depth understanding of how NPs influence the growth of plants.

关键词： Nanoplasctics Polyvinyl chloride Toxicity mechanisms Plant growth

Preparation of Self-limiting Heating Cables with Excellent Processability, Mechanical Properties and PTC Effect via Thermal and Electrical Treatments

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Chinese Journal of Polymer Science 2024年第4期42卷 511-520页

作者： Tian-hao Yang Tong Wu Qiang Fu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu610065China

Polymer/conductive filler composites have been widely used for the preparation of self-limiting heating cables with the positive temperature coefficient (PTC) effect. The control of conductive filler distribution and network in polymer matrix is the most critical for performance of PTC materials. In order to compensate for the destruction of the filler network structure caused by strong shearing during processing, an excessive conductive filler content is usually added into the polymer matrix, which in turn sacrifices its processability and mechanical properties. In this work, a facile post-treatment of the as-extruded cable, including thermal and electrical treatment to produce high-density polyethylene (HDPE)/carbon black (CB) cable with excellent PTC effect, is developed. It is found for the as-extruded sample, the strong shearing makes the CB particles disperse uniformly in HDPE matrix, and 25 wt% CB is needed for the formation of conductive paths. For the thermal-treated sample, a gradually aggregated CB filler structure is observed, which leads to the improvement of PTC effect and the notable reduction of CB content to 20 wt%. It is very interesting to see that for the sample with combined thermal and electrical treatment, CB particles are agglomerated and oriented along the electric field direction to create substantial conductive paths, which leads to a further decrease of CB content down to 15 wt%. In this way, self-limiting heating cables with excellent processability, mechanical properties and PTC effect have simultaneously been achieved.

关键词： Self-limiting heating cables Positive temperature coefficient Thermal treatment Electrical treatment

Optimization of Hydrocracking Process for Enhanced BTX Production from Coal Tar-Derived Hydrorefined Products

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 139-151页

作者： Wu hao Wei Hongyuan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

Hydroconversion of coal tar to produce aromatic hydrocarbons(BTX)represents a crucial strategy for the highvalue hierarchical utilization of *** study focused on the hydrocracking of hydrorefined products derived from coal tar to enhance the production of benzene,toluene,and xylene(BTX).Various reaction conditions,including reaction temperature,hydrogen pressure,space velocity,and hydrogen-to-oil volume ratio,were systematically explored to optimize BTX yields while also considering the process’s economic *** results indicate that increasing the reaction temperature from 360℃ to 390℃ significantly favors the production of BTX,with yields increasing from 21.42%to 41.14%.Similarly,an increase in hydrogen pressure from 4 MPa to 6 MPa boosts BTX production,with yields rising from 36.31%to 41.14%.Reducing the space velocity from 2 h^(-1) to 0.5 h^(-1) also favors the BTX production process,with yields increasing from 37.96%to 45.13%.Furthermore,raising the hydrogen-to-oil volume ratio from 750 to 1500 improves BTX yields from 41.61%to 45.44%.Through economic analysis,the optimal conditions for BTX production were identified as a reaction temperature of 390℃,hydrogen pressure of 5-6 MPa,space velocity of 1 h^(-1),and hydrogen-to-oil volume ratio of 1000,achieving a BTX yield of 43.73%.This investigation highlights the importance of a holistic evaluation of hydrocracking conditions to optimize BTX ***,the findings offer valuable insights for the design and operation of industrial hydrocracking processes aimed at efficiently converting coal tar-derived hydrorefined feedstock into BTX.

关键词： coal tar hydrocracking BTX process optimization economic assessment

Strategic regulation of nitrogen-containing intermediates for enhanced nitrate reduction over Co_(3)O_(4)/SiC catalyst having multiple active centers

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Journal of Energy Chemistry 2024年第9期96卷 291-299页

作者： Ming-hao Guan hao-Nan Xu Jin Liu Tao Wu An-Hui Lu State Key Laboratory of Fine Chemicals Liaoning Key Laboratory for Catalytic Conversion of Carbon ResourcesSchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina

Regulating the intermediates involved in the electrocatalytic nitrate reduction reaction(NO_(3)RR)is crucial for the enhancement of reaction ***,it remains a great challenge to regulate the reaction intermediates through active site manipulation on the surface of the ***,a family of n%-Co_(3)O_(4)/SiC(n=5,8,12,20)catalysts with a delicate percentage of Co^(2+)and Co^(3+)were prepared for NO_(3)*** found that Co^(3+)primarily acts as the active site for NO_(3)^(−)reduction to NO_(2)^(−),while Co^(2+)is responsible for the conversion of NO_(2)^(−)to NH_(3).Moreover,the conversion of these intermediates over the active sites is autonomous and separately *** processes synergistically accomplish the reduction of nitrate ions to synthesize *** the experimental studies and density functional theory(DFT)calculations,it is discovered the pathway(^(*)NHO→^(*)NHOH→^(*)NH_(2)OH→^(*)NH_(2)→^(*)NH_(3))is more favorable due to the lowerΔG value(0.25 eV)for the rate-limiting step(^(*)NO→^(*)NHO).The NH_(3)yield rate of 8%-Co_(3)O_(4)/SiC reached 1.08 mmol/(cm^(2)h)with a Faradaic efficiency of 96.4%at−0.89 V versus the reversible hydrogen electrode(RHE),surpassing those of most reported non-noble NO_(3)RR *** strategy not only provides an efficient catalyst for NO_(3)RR but also serves as an illustrative model for the regulation of multi-step reaction intermediates through the design of distinct active sites,thereby presenting a new approach to enhance the efficiency of intricate reactions.

关键词： Electrocatalysis Nitratereduction Co_(3)O_(4)/SiC catalysts Intermediates control

Deep Learning and Tensor-Based Multiple Clustering Approaches for Cyber-Physical-Social Applications

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Computers, Materials & Continua 2024年第3期78卷 4109-4128页

作者： Hongjun Zhang hao Zhang Yu Lei hao Ye Peng Li Desheng Shi School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing210023China China Communications Services Co. Ltd.Beijing100071China China Communications Services Hexin Science&Technology Co. Ltd.Hefei230031China

The study delves into the expanding role of network platforms in our daily lives, encompassing various mediums like blogs, forums, online chats, and prominent social media platforms such as Facebook, Twitter, and Instagram. While these platforms offer avenues for self-expression and community support, they concurrently harbor negative impacts, fostering antisocial behaviors like phishing, impersonation, hate speech, cyberbullying, cyberstalking, cyberterrorism, fake news propagation, spamming, and fraud. Notably, individuals also leverage these platforms to connect with authorities and seek aid during disasters. The overarching objective of this research is to address the dual nature of network platforms by proposing innovative methodologies aimed at enhancing their positive aspects and mitigating their negative repercussions. To achieve this, the study introduces a weight learning method grounded in multi-linear attribute ranking. This approach serves to evaluate the significance of attribute combinations across all feature spaces. Additionally, a novel clustering method based on tensors is proposed to elevate the quality of clustering while effectively distinguishing selected features. The methodology incorporates a weighted average similarity matrix and optionally integrates weighted Euclidean distance, contributing to a more nuanced understanding of attribute importance. The analysis of the proposed methods yields significant findings. The weight learning method proves instrumental in discerning the importance of attribute combinations, shedding light on key aspects within feature spaces. Simultaneously, the clustering method based on tensors exhibits improved efficacy in enhancing clustering quality and feature distinction. This not only advances our understanding of attribute importance but also paves the way for more nuanced data analysis methodologies. In conclusion, this research underscores the pivotal role of network platforms in contemporary society, emp

关键词： Network platform tensor-based clustering weight learning multi-linear euclidean

Coexistence of All-Order Topological States in a Three-Dimensional Phononic Topological Crystalline Insulator

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Research 2024年第2期2023卷 511-518页

作者： Hua-Shan Lai hao Chen Chu-hao Xia Si-Yuan Yu Cheng He Yan-Feng Chen National Laboratory of Solid State Microstructures&Department of Materials Science and Engineering Nanjing UniversityNanjng 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjng 210093China Jiangsu Key Laboratory of Artificial Functional Materials Nanjing University Nanjing 210093China

Classical-wave topological materials lacking intrinsic half-integer spins are less robust while more ***,we explore a single 3-dimensional phononic topological crystalline insulator that simultaneously exhibits a whole family of first-order quadratic surface,second-order hinge,and third-order corner states within the same *** a topological crystalline insulator hosting all-order phases originates from the different topological nature when hierarchically projected onto different facets and lower dimensions,thus free from trivial cladding *** work offers an ideal platform for either robust wave propagation or localization in on-demand dimensions and may facilitate dimension division multiplexing technology.

关键词： topological dimensions crystalline

A real-time calibration method based on time-to-digital converter for accelerator timing system

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Nuclear Science and Techniques 2024年第9期35卷 127-140页

作者： Qi-hao Duan Liang Ge Yan-hao Jia Jie-Yu Zhu Wei Zhang Institute of modern physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The high-intensity heavy-ion accelerator facility(HIAF)is a scientific research facility complex composed of multiple cas-cade accelerators of different types,which pose a scheduling problem for devices distributed over a certain range of 2 km,involving over a hundred *** white rabbit,a technology-enhancing Gigabit Ethernet,has shown the capability of scheduling distributed timing devices but still faces the challenge of obtaining real-time synchronization calibration param-eters with high *** study presents a calibration system based on a time-to-digital converter implemented on an ARM-based System-on-Chip(SoC).The system consists of four multi-sample delay lines,a bubble-proof encoder,an edge controller for managing data from different channels,and a highly effective calibration module that benefits from the SoC *** performance was evaluated with an average RMS precision of 5.51 ps by measuring the time intervals from 0 to 24,000 ps with 120,000 data for every *** design presented in this study refines the calibration precision of the HIAF timing *** eliminates the errors caused by manual calibration without efficiency loss and provides data support for fault *** can also be easily tailored or ported to other devices for specific applications and provides more space for developing timing systems for particle accelerators,such as white rabbits on HIAF.

关键词： HIAF White rabbit Calibration system Time-to-digital converter(TDC)