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Rare Metals 2024年第7期43卷 3107-3117页

作者： xin-yang Liu jing-Wei Liu Gang Li jing-Xiang Zhao College of Chemistry and Chemical Engineering Harbin Normal UniversityHarbin 150025China

Subnanometer metal clusters play an increasingly important role in heterogeneous catalysis due to their high catalytic activity and *** this work,by means of the density functional theory(DFT) calculations,the catalytic activities of transition metal clusters with precise numbers of atoms supported on graphdiyne(TM_(1-4)@GDY,TM=V,Cr,Mn,Fe,Co,Ni,Cu,Ru,Rh,Pd,Ir,Pt) were investigated for oxygen evolution reactions(OER),oxygen reduction reactions(ORR) and hydrogen evolution reactions(HER).The computed results reveal that the Pd_(2),Pd_(4) and Pt_(1) anchored graphdiyne can serve as trifunctional catalysts for OER/ORR/HER with the overpotentials of 0.49/0.37/0.06,0.45/0.33/0.12 and 0.37/0.43/0.01 V,respectively,while Pd_(1) and Pt_(2)@graphdiyne can exhibit excellent catalytic performance for water splitting(OER/HER) with the overpotentials of 0.55/0.17 and 0.43/0.03 *** addition,Ni_(1) and Pd_(3) anchored GDY can perform as bifunctional catalysts for metal-air cells(OER/ORR) and fuels cells(ORR/HER) with the overpotentials of 0.34/0.32 and 0.42/0.04 V,***,by precisely controlling the numbers of atoms in clusters,the TM_(1-4) anchored graphdiyne can serve as promising multifunctional electrocatalysts for OER/ORR/HER,which may provide an instructive strategy to design catalysts for the energy conversation and storage devices.

关键词： Density functional theory Graphdiyne Single-cluster catalysts Multifunctional electrocatalysts Overpotential

Efficient construction of calcium fluoride nanoaggregates for enhanced water vapor adsorption

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Particuology 2024年第6期89卷 191-197页

作者： Dan-Lei yang jing Cao Rong-Kun Liu Jie-xin Wang School of Life Sciences and Chemical Engineering Jiangsu Second Normal UniversityNanjing210013China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing100029China Petrochemical Research Institute PetroChinaBeijing102206China

Calcium fluoride(CaF_(2))is an ideal adsorbent for the dehydration of gaseous hydrogen fluoride(HF)containing water *** this work,a novel CaF_(2)absorbent,spherical CaF_(2)nanoaggregates(NAs)with a closely packed structure,was proposed and efficiently fabricated by spray drying *** the building blocks of CaF_(2)NAs,the CaF_(2)nanoparticles(NPs)were prepared by the addition of excess calcium ions(Ca^(2+))or fluorine ions(F−)in the *** results indicated that the CaF_(2)NPs synthesized by excess Ca^(2+)and the corresponding NAs exhibited much better water vapor adsorption properties than their counterparts by excess F−,owing to higher zeta *** importantly,whether excess Ca^(2+)or F^(−),CaF_(2)NAs had further enhanced water vapor adsorption capacity compared to primary CaF_(2)NPs,possibly owing to their unique nano-micro secondary structures and higher surface *** work has great potential in the development of high-performance absorbents for separating moisture from corrosive gas HF.

关键词： CaF_(2)nanoaggregates Water vapor adsorption Spray drying

Deep learning for joint channel estimation and feedback in massive MIMO systems

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Digital Communications and Networks 2024年第1期10卷 83-93页

作者： Jiajia Guo Tong Chen Shi jin Geoffrey Ye Li xin Wang Xiaolin Hou National Mobile Communications Research Laboratory Southeast UniversityNanjing210096China Department of Electrical and Electronic Engineering Imperial College LondonLondonSW72AZUK DOCOMO Beijing Communications Laboratories Co. LtdBeijingChina

The great potentials of massive Multiple-Input Multiple-Output(MIMO)in Frequency Division Duplex(FDD)mode can be fully exploited when the downlink Channel State Information(CSI)is available at base ***,the accurate CsI is difficult to obtain due to the large amount of feedback overhead caused by massive *** this paper,we propose a deep learning based joint channel estimation and feedback framework,which comprehensively realizes the estimation,compression,and reconstruction of downlink channels in FDD massive MIMO *** networks are constructed to perform estimation and feedback explicitly and *** explicit network adopts a multi-Signal-to-Noise-Ratios(SNRs)technique to obtain a single trained channel estimation subnet that works well with different SNRs and employs a deep residual network to reconstruct the channels,while the implicit network directly compresses pilots and sends them back to reduce network *** module is also designed to generate data-bearing *** results show that the two proposed networks exhibit excellent performance of reconstruction and are robust to different environments and quantization errors.

关键词： Channel estimation CSI feedback Deep learning Massive MIMO FDD

Nearly lattice-defect-free MOF membranes

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Science China Chemistry 2024年第3期67卷 741-743页

作者： Yuzhang Zhu yang Liu Jian jin i-Lab Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

Membrane technology has widely accepted as the most energy efficient technology for the separation of ions or molecules. As the core of the membrane technology, the chemical and structure nature of membrane materials determines the application and energy-efficiency of the technology. An advanced membrane that has a remarkable ability to selectively differentiate ions and molecules can significantly enhance the separation technology and revolutionize industrial separation processes.

关键词： processes. separation defect

Research on Sarcasm Detection Technology Based on Image-Text Fusion

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Computers, Materials & Continua 2024年第6期79卷 5225-5242页

作者： Xiaofang jin Yuying yang YinanWu Ying Xu School of Information and Communication Engineering Communication University of ChinaBeijing100024China Cable Television Technology Research Institute Academy of Broadcasting ScienceBeijing100053China

The emergence of new media in various fields has continuously strengthened the social aspect of social *** tend to express emotions in social interactions,and many people even use satire,metaphors,and other techniques to express some negative emotions,it is necessary to detect sarcasm in social comment *** sarcasm,the more reference data modalities used,the better the experimental *** paper conducts research on sarcasm detection technology based on image-text fusion *** effectively utilize the features of each modality,a feature reconstruction output algorithm is *** algorithm is based on the attention mechanism,learns the low-rank features of another modality through cross-modality,the eigenvectors are reconstructed for the corresponding modality through weighted *** only the image modality in the dataset is used,the preprocessed data has outstanding performance in reconstructing the output model,with an accuracy rate of 87.6%.When using only the text modality data in the dataset,the reconstructed output model is optimal,with an accuracy rate of 85.2%.To improve feature fusion between modalities for effective classification,a weight adaptive learning algorithm is *** algorithm uses a neural network combined with an attention mechanism to calculate the attention weight of each modality to achieve weight adaptive learning purposes,with an accuracy rate of 87.9%.Extensive experiments on a benchmark dataset demonstrate the superiority of our proposed model.

关键词： Sentiment analysis sarcasm detection feature fusion feature reconstruction

Video Colorization:A Survey

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Journal of Computer Science & Technology 2024年第3期39卷 487-508页

作者：彭中正杨艺新唐金辉潘金山 School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing210094China CCF IEEE ACM

Video colorization aims to add color to grayscale or monochrome *** existing methods have achieved substantial and noteworthy results in the field of image colorization,video colorization presents more formidable obstacles due to the additional necessity for temporal ***,there is rarely a systematic review of video colorization *** this paper,we aim to review existing state-of-the-art video colorization *** addition,maintaining spatial-temporal consistency is pivotal to the process of video *** gain deeper insight into the evolution of existing methods in terms of spatial-temporal consistency,we further review video colorization methods from a novel *** colorization methods can be categorized into four main categories:optical-flow based methods,scribble-based methods,exemplar-based methods,and fully automatic ***,optical-flow based methods rely heavily on accurate optical-flow estimation,scribble-based methods require extensive user interaction and modifications,exemplar-based methods face challenges in obtaining suitable reference images,and fully automatic methods often struggle to meet specific colorization *** also discuss the existing challenges and highlight several future research opportunities worth exploring.

关键词： video colorization deep convolutional neural network spatial-temporal consistency

Lipase and photodecarboxylase coexpression: A potential strategy for alkane-based biodiesel production from natural triglycerides

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Chinese Journal of Chemical Engineering 2024年第3期67卷 238-246页

作者： Yong-Yi Zeng xin-Yi Xu jin-Xuan Xie Wen-Li Chen Lan Liu xin-Jian Yin Bi-Shuang Chen School of Marine Sciences Sun Yat-Sen UniversityZhuhai 519080China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Alkane-based biodiesel is considered the next generation of biodiesel owing to its potential environmental benefits and the fact that it exhibits much higher specific caloric values than traditional ***,the formidable obstacle impeding the commercialization of this cutting-edge fuel alternative lies in the cost associated with its *** this study,an engineered strain Escherichia coli(***)showcasing harmonized coexpression of a lipase(from Thermomyces lanuginosus lipase,TLL)and a fatty acid photodecarboxylase(from Chlorella variabilis,CvFAP)was first constructed to transform triglycerides into *** potential of *** BL21(DE3)/pRSFDuet-1-TLL-CvFAP for alkane synthesis was evaluated with tripalmitin as a model substrate under various process *** a comprehensive examination of the reaction parameters,the scope of the biotransformation was expanded to‘real’substrates(vegetable oils).The results showed that bioderived oils can be transformed into alkanes with high yields(0.80-10.20 mmol·L^(-1))under mild conditions(35℃,pH 8.0,and 36 h)and blue light *** selected processes were performed on an increased lab scale(up to 100 ml)with up to 24.77 mmol·L^(-1) tripalmitin,leading to a yield of 18.89 mmol·L^(-1) *** the employment of a method for efficiently producing alkanes under mild conditions and a simple procedure to isolate alkanes from the reaction system,the utilization of sustainable biomass as a fundamental feedstock emerges as the primary solution to lower the cost of alkane-based ***,this study proposes a readily implementable and highly effective approach for alkane-based biodiesel production.

关键词： Alkane-based biodiesel Renewable biomass Co-overexpression Lipase Photodecarboxylase

Exploring the Lagged Correlation Between Baidu Index and Influenza-Like Illness-China,2014-2019

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China CDC weekly 2024年第26期6卷 629-634页

作者： Xuan Han Jiao yang Yan Luo Dazhu Huo Xuya Yu Xuancheng Hu Ling xin Liuyang yang Hualei xin Ting Zhang Zhongjie Li Weizhong yang School of Population Medicine and Public Health Chinese Academy of Medical Sciences(CAMS)&Peking Union Medical CollegeBeijingChina School of Health Policy and Management Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina Department of management science and information system Faculty of Management and EconomicsKunming University of Science and TechnologyKunming CityYunnan ProvinceChina

Introduction:This study investigated the lagged correlation between Baidu Index for influenza-related keywords and influenza-like illness percentage(ILI%)across regions in *** aim is to establish a scientific foundation for utilizing Baidu Index as an early warning tool for influenza-like illness ***:In this study,data on ILI%and Baidu Index were collected from 30 provincial-level administrative divisions(PLADs)spanning April 2014 to March *** Baidu Index was categorized into Overall Index,Ordinary Index,Prevention Index,Symptom Index,and Treatment Index based on search query *** lagged correlation between the Baidu Index and ILI%was examined through the cross-correlation function(CCF)***:Correlating the Baidu Overall Index of 30 PLADs with ILI%revealed CCF values ranging from 0.46 to 0.86,with a median lag of 0.5 *** analysis indicated that the Prevention Index and Symptom Index exhibited quicker responses to ILI%,with median lags of−9 and−0.5 days,respectively,compared to 0 and 3 days for the Ordinary and Treatment *** median lag days between the Baidu Index and the ILI%were earlier in the northern PLADs compared to the southern ***:The Prevention and Symptom Indexes show promising predictive capabilities for influenzalike illness epidemics.

关键词： utilizing illness Baidu

Selective CO_(2)Electroreduction to Multi-Carbon Products on Organic-Functionalized CuO Nanoparticles by Local Micro-Environment Modulation

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Nano-Micro Letters 2024年第12期16卷 120-132页

作者： Shan Ren Xi Cao Qikui Fan Zhimao yang Fei Wang xin Wang Licheng Bai Jian yang Materials Interfaces Center Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongPeople’s Republic of China Key Laboratory of Functional Molecular Solids Ministry of EducationCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002AnhuiPeople’s Republic of China School of Physics Xi’an Jiaotong UniversityXi’an 710049ShaanxiPeople’s Republic of China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518071GuangdongPeople’s Republic of China

Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the parasitic hydrogen evolution reaction and facilitating a localized CO_(2)/CO concentration at the *** upon this approach,we developed surface-functionalized catalysts with exceptional activity and selectivity for electrocatalytic CO_(2)RR to C_(2+)in a neutral *** CuO nanoparticles coated with hexaethynylbenzene organic molecules(HEB-CuO NPs),a remarkable C_(2+)Faradaic efficiency of nearly 90%was achieved at an unprecedented current density of 300 mA cm^(-2),and a high FE(>80%)was maintained at a wide range of current densities(100-600 mA cm^(-2))in neutral environments using a flow ***,in a membrane electrode assembly(MEA)electrolyzer,86.14%FEC2+was achieved at a partial current density of 387.6 mA cm^(-2)while maintaining continuous operation for over 50 h at a current density of 200 mA cm^(-2).In-situ spectroscopy studies and molecular dynamics simulations reveal that reducing the coverage of coordinated K⋅H2O water increased the probability of intermediate reactants(CO)interacting with the surface,thereby promoting efficient C-C coupling and enhancing the yield of C_(2+)*** advancement offers significant potential for optimizing local micro-environments for sustainable and highly efficient C_(2+)production.

关键词： CO_(2)electroreduction to C_(2+) Neutral electrolyte Organic-functionalized CuO nanoparticles Local micro-environment

Clinical observation on 90 cases of primary dysmenorrhea treated by buccal acupuncture therapy:a randomized controlled study

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Journal of Traditional Chinese Medicine 2024年第1期44卷 172-181页

作者： yang Yi YE Huijun ZHENG Huiling jin Lihua Department of Obstetrics and Gynecology the Second Affiliated Hospital of Zhejiang Chinese Medical UniversityXinhua Hospital of Zhejiang ProvinceHangzhou 310005China

OBJECTIVE:To explore the short-term and long-term efficacy of buccal acupuncture therapy in the treatment of patients with primary dysmenorrhea(PD).METHODS:A total of 90 patients with PD who were admitted to the Second Affiliated Hospital of Zhejiang University of Traditional Chinese Medicine from January 2020 to December 2021 were included in this study and randomly divided into three groups,including the observation group,the control group,and the placebo group,with 30 patients in each *** in the observation group were treated according to the syndrome types of Traditional Chinese Medicine,those in the control group were treated with Saridon,and those in the placebo group received a *** visual analog scale(VAS)scores of these patients were evaluated at different time points(before treatment,5 min after needle retention,30 min after needle retention,1 h after treatment,2 h after treatment,1 d after treatment,and 2 d after treatment).The Cox Menstrual Symptom Scale(CMSS)scores were assessed before the treatment and after three courses of ***,these two scales were also evaluated during ***,the pain score and adverse reactions of these patients were assessed during ***:After treatment,the VAS and CMSS scores in the observation group decreased significantly(P<0.05)5 and 30 min after needle retention and after ***:Buccal acupuncture therapy is verified to have short-term efficacy in the treatment of *** addition,this therapy has an immediate analgesic effect and long-term efficacy in reducing the severity and frequency of PD.

关键词： buccal acupuncture therapy primary dysmenorrhea pain score randomized controlled trial