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Valorization of carbon dioxide with alcohols

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Chinese Chemical Letters 2024年第7期35卷 54-58页

作者： Daheng Wen Weiwei Fang Yongmei Liu Tao tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Utilizing CO_(2)for the production of bulky and valuable chemicals presents an attractive solution to address environmental and fossil energy *** the various approaches,direct carboxylation of alcohols with CO_(2)stands out as an eco-friendly process capable of efficiently producing carboxylic acids in a sustainable ***,the high dissociation energy of the C–O bond poses a significant challenge in this *** the past few decades,several strategies have been developed to activate alcohols and establish efficient catalytic systems for carboxylation with CO_(2).Nevertheless,the sporadic nature of reported approaches makes it difficult to determine the most effective *** perspective aims to provide an overview of the current state-of-the-art catalytic protocols for carboxylating alcohols with CO_(2),encompassing esterification,halogenation,and photocatalysis,while considering their respective advantages and *** aim to discern the most promising avenues for future development in this *** insights presented in this perspective will contribute to the advancement of efficient and sustainable carboxylation methods using CO_(2),leading to the production of valuable chemicals in future.

关键词： Carboxylation Carbon dioxide Alcohol Carboxylic acid Transition metal catalysis

Non-cooperative Game Based Optimal Dispatch Model for Integrated Energy Systems

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1195-1207页

作者： Jiandong Duan Qian Sun Chen Wu Yao Yang Siyu tu School of Electrical Engineering Xi’an University of TechnologyXi’an710056China IEEE CSEE

In order to improve the efficiency of energy utilization,the integrated energy system(IES)has *** IES typically acts as a whole system during operations,the subsystems are separated,and the interests of each system are *** this paper,considering the relationship between the various energy systems,non-cooperative game theory is used to establish the optimal dispatch *** proposed model mainly relies on the relationship between the cooperation and competition among various subsystems to obtain the maximum benefit they can ***,the basic definition is combined with the particle swarm optimization algorithm to solve the *** results show that the optimization strategy proposed in this paper can operate safely and reliably,and effectively distribute the benefits of each energy system.

关键词： Integrated energy system multi-energy complimentarily non-cooperative game theory

Machine learning-driven optimization of plasma-catalytic dry reforming of methane

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Journal of Energy Chemistry 2024年第9期96卷 153-163页

作者： Yuxiang Cai Danhua Mei Yanzhen Chen Annemie Bogaerts Xin tu Department of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK Research Group PLASMANT Department of ChemistryUniversity of AntwerpUniversiteitsplein 1BE-2610 Wilrijk-AntwerpBelgium College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816JiangsuChina

This study investigates the dry reformation of methane(DRM)over Ni/Al_(2)O_(3)catalysts in a dielectric barrier discharge(DBD)non-thermal plasma reactor.A novel hybrid machine learning(ML)model is developed to optimize the plasma-catalytic DRM reaction with limited experimental *** address the non-linear and complex nature of the plasma-catalytic DRM process,the hybrid ML model integrates three well-established algorithms:regression trees,support vector regression,and artificial neural networks.A genetic algorithm(GA)is then used to optimize the hyperparameters of each algorithm within the hybrid ML *** ML model achieved excellent agreement with the experimental data,demonstrating its efficacy in accurately predicting and optimizing the DRM *** model was subsequently used to investigate the impact of various operating parameters on the plasma-catalytic DRM *** found that the optimal discharge power(20 W),CO_(2)/CH_(4)molar ratio(1.5),and Ni loading(7.8 wt%)resulted in the maximum energy yield at a total flow rate of∼51 mL/***,we investigated the relative significance of each operating parameter on the performance of the plasma-catalytic DRM *** results show that the total flow rate had the greatest influence on the conversion,with a significance exceeding 35%for each output,while the Ni loading had the least impact on the overall reaction *** hybrid model demonstrates a remarkable ability to extract valuable insights from limited datasets,enabling the development and optimization of more efficient and selective plasma-catalytic chemical processes.

关键词： Plasma catalysis Machine learning Process optimization Dry reforming of methane Syngas production

SWG: an architecture for sparse weight gradient computation

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Science China(Information Sciences) 2024年第2期67卷 302-321页

作者： Weiwei WU Fengbin tu Xiangyu LI Shaojun WEI Shouyi YIN School of Integrated Circuits Tsinghua University Department of Electronic and Computer Engineering The Hong Kong University of Science and Technology

On-device training for deep neural networks(DNN) has become a trend due to various user preferences and scenarios. The DNN training process consists of three phases, feedforward(FF), backpropagation(BP), and weight gradient(WG) update. WG takes about one-third of the computation in the whole training process. Current training accelerators usually ignore the special computation property of WG and process it in a way similar to FF/BP. Besides, the extensive data sparsity existing in WG, which brings opportunities to save computation, is not well explored. Nevertheless, exploiting the optimization opportunities would meet three underutilization problems, which are caused by(1) the mismatch between WG data dimensions and hardware parallelism,(2) the full sparsity, i.e., the sparsity of feature map(Fmap),error map(Emap), and gradient, and(3) the workload imbalance resulting from irregular sparsity. In this paper, we propose a specific architecture for sparse weight gradient(SWG) computation. The architecture is designed based on hierarchical unrolling and sparsity-aware(HUSA) dataflow to exploit the optimization opportunities of the special computation property and full data sparsity. In HUSA dataflow, the data dimensions are unrolled hierarchically on the hardware architecture. A valid-data trace(VDT) mechanism is embedded in the dataflow to avoid the underutilization caused by the two-sided input sparsity. The gradient is unrolled in PE to alleviate the underutilization induced by output sparsity while maintaining the data reuse opportunities. Besides, we design an intra-and inter-column balancer(IIBLC) to dynamically tackle the workload imbalance problem resulting from the irregular sparsity. Experimental results show that with HUSA dataflow exploiting the full sparsity, SWG achieves a speedup of 12.23× over state-of-the-art gradient computation architecture, Train Ware. SWG helps to improve the energy efficiency of the state-of-the-art training accelerator LNPU from

关键词： CNN training gradient computation sparsity architecture

China stroke surveillance report 2021

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Military Medical Research 2024年第3期11卷 374-399页

作者： Wen-Jun tu Long-De Wang 无 Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China School of Public Health Peking UniversityBeijing 100191China Special Writing Group of China Stroke Surveillance Report

Since 2015,stroke has become the leading cause of death and disability in China,posing a significant threat to the health of its citizens as a major chronic non-communicable *** to the China Stroke High-risk Population Screening and Intervention Program,an estimated 17.8 million[95%confidence interval(CI)17.6–18.0million]adults in China had experienced a stroke in 2020,with 3.4 million(95%CI 3.3–3.5 million)experiencing their first-ever stroke and another 2.3 million(95%CI 2.2–2.4 million)dying as a ***,approximately 12.5%(95%CI 12.4%–12.5%)of stroke survivors were left disabled,as defined by a modified Rankin Scale score greater than 1,equating to 2.2 million(95%CI 2.1–2.2 million)stroke-related disabilities in *** the population ages and the prevalence of risk factors like diabetes,hypertension,and hyperlipidemia continues to rise and remains poorly controlled,the burden of stroke in China is also increasing.A large national epidemiological survey initiated by the China Hypertension League in 2017 showed that the prevalence of hypertension was 24.7%;the awareness,treatment,and control rates in hypertensive patients were:60.1%,42.5%,and 25.4%,respectively.A nationally representative sample of the Chinese mainland population showed that the weighted prevalence of total diabetes diagnosed by the American Diabetes Association criteria was 12.8%,suggesting there are 120 million adults with diabetes in China,and the awareness,treatment,and control rates in diabetic patients were:43.3%,49.0%,and 49.4%,***“Sixth National Health Service Statistical Survey Report in 2018”showed that the proportion of the obese population in China was 37.4%,an increase of 7.2 points from *** from 1599 hospitals in the Hospital Quality Monitoring System and Bigdata Observatory Platform for Stroke of China(BOSC)showed that a total of 3,418,432 stroke cases[mean age±standard error(SE)was(65.700±0.006)years,and 59.1%were male]were admitted dur

关键词： Stroke Epidemiological characteristics Treatment Prognosis China

Effect of Operation Parameters on the Thermal Characteristics in a Planar Solid Oxide Fuel Cell

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Journal of Thermal Science 2024年第5期33卷 1974-1989页

作者： WANG Mingyuan WANG Ke WANG Yongqing CHEN Jiangshuai AN Bo tu Shantung School of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Process Heat Transfer and Energy Saving of Henan Province Zhengzhou UniversityZhengzhou 450002China School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Pressure Systems and Safety(MOE) East China University of Science&TechnologyShanghai 200237China

Effective operation strategies in the solid oxide fuel cell(SOFC)can adjust the spatial distribution of temperature gradient favoring the long-term *** investigate the effects of different operating conditions on the thermal behavior inside SOFC,a three-dimensional model is developed in this *** model is verified by comparing it with the experimental *** heat generation rate and its variation under different operating conditions are *** combined effects of operating voltage and gas temperature are considered to be the key factor influencing the temperature *** to the original case,the temperature of SOFC decreases by 21.4 K when the fuel velocity reaches 5 m/*** the maximum temperature gradient increases by21.2%.Meanwhile,higher fuel velocities can eliminate about 32%of the area with higher temperature *** when the oxidant velocity reaches 7.5 m/s,the peak temperature gradient effectively decreases by 16.59%.Simultaneous adjustment of the oxidant and fuel velocities can effectively reduce the peak temperature gradient and increase the safety *** effects of operation conditions on the temperature gradient of the cell are clarified in this study,which can be a reference for further research on the reliability of SOFCs.

关键词： SOFC heat generation temperature gradient distribution heat source thermal behavior

A coupled Legendre-Laguerre polynomial method with analytical integration for the Rayleigh waves in a quasicrystal layered half-space with an imperfect interface

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1539-1556页

作者： Bo ZHANG Honghang tu Weiqiu CHEN Jiangong YU L.ELMAIMOUNI School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000Henan ProvinceChina Henan International Joint Laboratory of Advanced Electronic Packaging Materials Precision Forming Henan Polytechnic UniversityJiaozuo 454000Henan ProvinceChina Department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China Polydisciplinary Faculty of Ouarzazate Ibnou Zohr UniversityOuarzazate 45000Morocco

The Laguerre polynomial method has been successfully used to investigate the dynamic responses of a ***,it fails to obtain the correct stress at the interfaces in a layered half-space,especially when there are significant differences in material ***,a coupled Legendre-Laguerre polynomial method with analytical integration is *** Rayleigh waves in a one-dimensional(1D)hexagonal quasicrystal(QC)layered half-space with an imperfect interface are *** correctness is validated by comparison with available *** computation efficiency is *** dispersion curves of the phase velocity,displacement distributions,and stress distributions are *** effects of the phonon-phason coupling and imperfect interface coefficients on the wave characteristics are *** novel findings reveal that the proposed method is highly efficient for addressing the Rayleigh waves in a QC layered *** can save over 99%of the computation *** method can be expanded to investigate waves in various layered half-spaces,including earth-layered media and surface acoustic wave(SAW)devices.

关键词： coupled Legendre-Laguerre polynomial method analytical integration Rayleigh wave quasicrystal(QC)layered half-space imperfect interface

Vesicular drug delivery systems for oral absorption enhancement

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Chinese Chemical Letters 2024年第7期35卷 73-88页

作者： Linghui Zou Meng Cheng Kaili Hu Jianfang Feng Liangxing tu Jiangxi University of Chinese Medicine Nanchang 330006China Guangxi University of Chinese Medicine Nanning 530200China Shanghai University of Traditional Chinese Medicine Shanghai 201203China

Oral administration is the most acceptable route of drug delivery at this stage due to its convenience,safety,and ***,drugs given orally are exposed to a complex gastrointestinal environment,causing a tremendous challenge for their successful absorption into the *** the past decades,researchers have developed various novel pharmaceutical technologies to improve oral absorption,among which the vesicular drug delivery system(like liposomes,niosomes and transfersomes)has received extensive ***,there have been several investigations confirming the improved effect of vesicular drug delivery systems on oral drug ***,the clinical translation of oral vesicular drug delivery systems has been less impressive than implied by the positive results,and few vesicular formulations for oral use have been marketed *** this background,this article provides an overview of the current applications and challenges associated with the vesicular delivery systems available for oral drug delivery,specifically liposomes,niosomes,transfersomes,chitosomes and *** composition,formation mechanism,drug delivery advantages and application cases of these carriers in oral drug delivery are *** possible mechanisms by which vesicular carriers enhance oral drug absorption are analyzed in terms of the in vivo process of oral ***,the challenges that oral vesicular carriers now face,such as safety,undefined in vivo fate,and scale-up production,are summarized,while possible strategies to deal with them are *** reviewing the aforementioned,it can facilitate a more comprehensive knowledge of vesicular systems that can be used for oral drug delivery,providing a theoretical basis and reference for the design of oral formulations.

关键词： Vesicular Oral Mechanism Drug delivery Liposome Niosomes Transfersomes Chitosomes Bilosomes

Insulation Design Rule for a Spacer in SF_(6)/N_(2)-filled DC Gas Insulated Apparatus

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 727-735页

作者： Hongyang Zhou Guoming Ma Meng Zhang Cong Wang Youping tu Chengrong Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources and the Beijing Key Laboratory of High Voltage and EMC North China Electric Power UniversityBeijing 102206China

A recurring challenge of a DC SF_(6)/N_(2)-filled GIS/GIL apparatus is the charge accumulation at DC *** conventional design rules and knowledge of AC spacers may not be applicable for this new type of apparatus.A novel design rule is proposed considering the effect of accumulated charge on the threshold of electric field strength being resistant to the superposed voltage.A surface charge accumulation simulation model is introduced,and the key parameters in the simulation model are *** addition,an experimental platform for a 100 kV spacer flashover test is *** flashover tests under superimposed voltage with opposing polarities are carried out,and the withstanding voltage of the spacer is ***,based on the proposed model,the threshold of the surface electric field strength(tangential component)on the DC spacer in SF_(6)/N_(2) mixed gases is *** a reliable insulation design of a DC GIS/GIL apparatus filled with 0.7 MPa SF_(6)/N_(2),the threshold of surface electric field strength on the DC spacer is 12 kV/*** insulation design rule can be referenced in the design of a high-voltage DC SF_(6)/N_(2)-filled GIS/GIL apparatus.

关键词： Charge accumulation DC spacer flashover voltage SF_(6)/N_(2) threshold of surface electric field strength