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Nitrogen-doped carbon dots as photocatalysts for organic synthesis:Effect of nitrogen content on catalytic activity

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Nano Research 2024年第6期17卷 4825-4833页

作者： kai-kai Niu Chao-Qun Ma Rui-Zhi Dong Hui Liu Sheng-Sheng Yu Ling-Bao Xing School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China

Regulating the doping of carbon dots(CDs)and the generation of reactive oxygen species(ROS)is essential to selectively control their application in photocatalytic organic *** study successfully synthesized five newly developed nitrogen-doped carbon dots(CDs 1-5)with varying nitrogen content,which have the ability to generate ROS when exposed to light radiation,specifically superoxide anion radicals(O_(2)•-)and singlet oxygen(^(1)O_(2)).The utilization of the aforementioned nitrogen-doped CDs as photocatalysts enables the realization of their potential in facilitating efficient photocatalytic organic ***,it was observed that the photocatalytic efficiency exhibited a gradual decrease when the nitrogen content in the CDs *** order to provide more evidence for this claim,we employed a set of five CDs in the context of photocatalytic dehalogenation ofα-bromoacetophenone,photocatalytic oxidative coupling reaction of amines to imines,photooxidation reaction of sulfides to sulfoxides,and cross-dehydrogenation coupling(CDC)reaction,in which it was further observed that there was a steady decrease in the yields of photocatalytic organic reactions as the nitrogen content in CDs ***,CDs 1 exhibited the best photocatalytic efficiency,thereby reinforcing the hypothesis that a higher nitrogen content corresponds to a decreased catalytic *** study not only investigates the impact of the nitrogen content on the catalytic performance of CDs,but also offers valuable insights for the future utilization of CDs for photocatalytic organic reactions in water.

关键词： carbon dots nitrogen-doped reactive oxygen species photocatalysis

Random Forest-Based Fatigue Reliability-Based Design Optimization for Aeroengine Structures

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 665-684页

作者： Xue-Qin Li Lu-kai Song School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong999077China Research Institute of Aero-Engine Beihang UniversityBeijing100191China

Fatigue reliability-based design optimization of aeroengine structures involves multiple repeated calculations of reliability degree and large-scale calls of implicit high-nonlinearity limit state function,leading to the traditional direct Monte Claro and surrogate methods prone to unacceptable computing efficiency and *** this case,by fusing the random subspace strategy and weight allocation technology into bagging ensemble theory,a random forest(RF)model is presented to enhance the computing efficiency of reliability degree;moreover,by embedding the RF model into multilevel optimization model,an efficient RF-assisted fatigue reliability-based design optimization framework is *** the low-cycle fatigue reliability-based design optimization of aeroengine turbine disc as a case,the effectiveness of the presented framework is *** reliabilitybased design optimization results exhibit that the proposed framework holds high computing accuracy and computing *** current efforts shed a light on the theory/method development of reliability-based design optimization of complex engineering structures.

关键词： Random forest reliability-based design optimization ensemble learning machine learning

Regulation of aging by NELF-A and RNA polymerase Ⅱ elongation

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Neural Regeneration Research 2024年第7期19卷 1415-1416页

作者： Chin-Tong Ong Zhen-kai Ngian Temasek Life Sciences Laboratory and Department of Biological Sciences National University of SingaporeSingaporeSingapore Department of Genetics Harvard Medical SchoolBostonMAUSA Institute of Molecular and Cell Biology Agency for ScienceTechnology and ResearchSingaporeSingapore

Epigenetic regulation of aging:Aging is defined as the gradual decline of physiological function and cellular integrity,causing o rganismal vulnerability to age-onset diseases and *** in different animal models have l... 详细信息

关键词： aging twelve integrity

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Mobile Crowdsourcing Task Allocation Based on Dynamic Self-Attention GANs

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Computers, Materials & Continua 2024年第4期79卷 607-622页

作者： kai Wei Song Yu Qingxian Pan School of Computer and Control Engineering Yantai UniversityYantai264005China School of Computer and Information Science Southwest UniversityChongqing400715China

Crowdsourcing technology is widely recognized for its effectiveness in task scheduling and resource *** traditional methods for task allocation can help reduce costs and improve efficiency,they may encounter challenges when dealing with abnormal data flow nodes,leading to decreased allocation accuracy and *** address these issues,this study proposes a novel two-part invalid detection task allocation *** the first step,an anomaly detection model is developed using a dynamic self-attentive GAN to identify anomalous *** to the baseline method,the model achieves an approximately 4%increase in the F1 value on the public *** the second step of the framework,task allocation modeling is performed using a twopart graph matching *** phase introduces a P-queue KM algorithm that implements a more efficient optimization *** allocation efficiency is improved by approximately 23.83%compared to the baseline *** results confirm the effectiveness of the proposed framework in detecting abnormal data nodes,enhancing allocation precision,and achieving efficient allocation.

关键词： Mobile crowdsourcing task allocation anomaly detection GAN attention mechanisms

Earth-abundant Zn-dipyrrin chromophores for efficient CO2 photoreduction

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National Science Review 2024年第6期11卷 214-222页

作者： Song Guo Fu-Gui Zeng Xiao-Di Li kai-kai Chen Ping Wang Tong-Bu Lu Zhi-Ming Zhang Institute for New Energy Materials and Low Carbon Technologies School of Materials Science& Engineering Tianjin University of Technology

The development of strong sensitizing and Earth-abundant antenna molecules is highly desirable for CO2reduction through artificial photosynthesis. Herein, a library of Zn–dipyrrin complexes（Z-1-Z-6） are rationally designed via precisely controlling their molecular configuration to optimize strong sensitizing Earth-abundant photosensitizers. Upon visible-light excitation, their special geometry enables intramolecular charge transfer to induce a charge-transfer state, which was first demonstrated to accept electrons from electron donors. The resulting long-lived reduced photosensitizer was confirmed to trigger consecutive intermolecular electron transfers for boosting CO2-to-CO conversion. Remarkably, the Earth-abundant catalytic system with Z-6 and Fe-catalyst exhibits outstanding performance with a turnover number of >20 000 and 29.7% quantum yield, representing excellent catalytic performance among the molecular catalytic systems and highly superior to that of noble-metal photosensitizer Ir（ppy）2（bpy）+under similar conditions. Experimental and theoretical investigations comprehensively unveil the structure–activity relationship, opening up a new horizon for the development of Earth-abundant strong sensitizing chromophores for boosting artificial photosynthesis.

关键词： Zn complex photocatalysis CO2 reduction charge transfer photosensitizer

Adult sigmoid intussusception resembling rectal prolapse:A case report

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World Journal of Clinical Cases 2024年第6期12卷 1163-1168页

作者： Tsung-Jung Tsai Yu shih Liu Department of Surgery Changhua Christian HospitalChanghua 500209Taiwan Department of Colorectal Surgery Changhua Christian HospitalChanghua 500209Taiwan

BACKGROUND Rectal prolapse arises from benign *** symptoms of internal intussusception mirror those of rectal prolapse,a misdiagnosis is possible,especially under limited clinical *** is crucial to recognize and differentiate rectal prolapse from internal intussusception because the two diagnoses have different ***,we describe a case of adult sigmoid intussusception presenting as rectal *** SUMMARY A 64-year-old woman with no known medical history visited a gastrointestinal outpatient department due to hard bloody stool defecation for 1 wk followed by constipation for 3 *** revealed a huge polypoid ulcerated tumor at the sigmoid colon with lumen *** patient was admitted due to postprocedural dull abdominal *** to failed colonoscopy reduction and stent insertion,the patient underwent sigmoid colon resection with primary end-to-end anastomosis,with the transverse colostomy pathological report showing adenocarcinoma,*** recovered well from the operation and was discharged with regular outpatient clinic *** Presentation and manifestation of sigmoid intussusception may resemble that of rectal prolapse,necessitating careful observation due to distinct prognostic implications.

关键词： Sigmoid intussusception Rectal prolapse Endoscopic reduction Adenocarcinoma Case report

A Robust Framework for Multimodal Sentiment Analysis with Noisy Labels Generated from Distributed Data Annotation

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2965-2984页

作者： kai Jiang Bin Cao Jing Fan School of Computer Science and Technology Zhejiang University of TechnologyHangzhou310023China

Multimodal sentiment analysis utilizes multimodal data such as text,facial expressions and voice to detect people’s *** the advent of distributed data collection and annotation,we can easily obtain and share such multimodal ***,due to professional discrepancies among annotators and lax quality control,noisy labels might be *** research suggests that deep neural networks(DNNs)will overfit noisy labels,leading to the poor performance of the *** address this challenging problem,we present a Multimodal Robust Meta Learning framework(MRML)for multimodal sentiment analysis to resist noisy labels and correlate distinct modalities ***,we propose a two-layer fusion net to deeply fuse different modalities and improve the quality of the multimodal data features for label correction and network ***,a multiple meta-learner(label corrector)strategy is proposed to enhance the label correction approach and prevent models from overfitting to noisy *** conducted experiments on three popular multimodal datasets to verify the superiority of ourmethod by comparing it with four baselines.

关键词： Distributed data collection multimodal sentiment analysis meta learning learn with noisy labels

Fast Blood Oxygenation through Hemocompatible Asymmetric Polymer of Intrinsic Microporosity Membranes

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Research 2024年第1期2023卷 261-270页

作者： Xinxi huang Junping huang Pengcheng Su Wanbin Li Guangdong Key Laboratory of Environmental Pollution and Health School of EnvironmentJinan UniversityGuangzhou 511443China

Membrane technology has attracted considerable attention for chemical and medical applications,among *** organs play important roles in medical science.A membrane oxygenator,also known as artificial lung,can replenish O_(2) and remove CO_(2) of blood to maintain the metabolism of patients with cardiopulmonary ***,the membrane,a key component,is subjected to inferior gas transport property,leakage propensity,and insufficient *** this study,we report efficient blood oxygenation by using an asymmetric nanoporous membrane that is fabricated using the classic nonsolvent-induced phase separation method for polymer of intrinsic *** intrinsic superhydrophobic nanopores and asymmetric configuration endow the membrane with water impermeability and gas ultrapermeability,up to 3,500 and 1,100 gas permeation units for CO_(2) and O_(2),***,the rational hydrophobic–hydrophilic nature,electronegativity,and smoothness of the surface enable the substantially restricted protein adsorption,platelet adhesion and activation,hemolysis,and thrombosis for the ***,during blood oxygenation,the asymmetric nanoporous membrane shows no thrombus formation and plasma leakage and exhibits fast O_(2) and CO_(2) transport processes with exchange rates of 20 to 60 and 100 to 350 ml m^(−2) min^(−1),respectively,which are 2 to 6 times higher than those of conventional *** concepts reported here offer an alternative route to fabricate high-performance membranes and expand the possibilities of nanoporous materials for membrane-based artificial organs.

关键词： porosity asymmetric Oxygen

Prescribed-time leader-following consensus of linear multi-agent systems by bounded linear time-varying protocols

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Science China(Information Sciences) 2024年第1期67卷 140-153页

作者： kai ZHANG Bin ZHOU Xuefei YANG Guangren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology

This paper considers the prescribed-time leader-following consensus problem of input-constrained linear multi-agent systems under generally directed communication topology in two cases:the Laplacian matrix related to the entire communication topology between agents is either known or *** particular,the consensus problem for the former case is solved by a novel bounded linear time-varying(LTV) protocol,where the feedback gain is formulated by the parametric Lyapunov equation and the knowledge of the Laplacian ***,by utilizing a distributed observer,a fully bounded LTV protocol is proposed for the latter *** should be noted that,compared with the existing results,the system under consideration is more general,the designed protocols are linear,and the consensus problem is accomplished even in a fully distributed ***,the effectiveness of the proposed approach is verified by a numerical example.

关键词： leader-following consensus time-vary feedback prescribed-time control fully distributed consensus