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Alliance of atomic-scale/nanoscale Fe/Co active sites with hierarchically porous N-doped carbon frameworks for efficient electrocatalytic oxygen reduction

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Rare Metals 2023年第11期42卷 3766-3779页

作者： Hai-Hua Yang xiao-Rong Qian Na Zhang xia-ting jia Zhi-Yan Wen xiao-Bo Chen Min-Jie Zhou Key Laboratory of Hunan Province for Advanced Carbon-Based Functional Materials Hunan Institute of Science and TechnologyYueyang414006China School of Chemistry and Chemical Engineering Hunan Institute of Science and TechnologyYueyang414006China School of Physics and Electronic Science Hunan Institute of Science and TechnologyYueyang414006China Department of Chemistry University of Missouri-Kansas CityKansas City64111USA

Ingenious establishment of transition metal-nitrogen-carbon electrocatalysts with diverse catalytic active sites and hierarchically porous frameworks is highly significant to boost the oxygen reduction reaction(ORR)in Zn-air batteries(ZABs).In this study,Fe/Co co-doped zeolitic imidazolium frameworks(ZIFs)and graphitic carbon nitride(g-C_(3)N_(4))were integrated and pyrolyzed to construct carbon-based electrocatalysts containing Fe,Co and N elements(labelled as Co-CoFe@NRPC),in which atomic-sc ale FeN_x and CoN_x,and nano scale metallic Co and CoFe alloy moieties were aligned with hierarchically porous N-doped carbon frameworks constructed by interconnected micropolyhedrons,nano tubes and *** diverse active moieties guaranteed excellent intrinsic catalytic activity,while the hierarchically porous N-doped carbon frameworks ensured admirable accessibility of the catalytic active sites,excellent electrical conductivity,satisfactory mass transport and good ***,the optimized Co-CoFe@NRPC-90(with 90 mg g-C_(3)N_(4) added)electrocatalyst exhibited excellent ORR performance with a high half-wave potential of 885 mV(*** hydrogen electrode(RHE)),diffusion-limiting current density of 6.15 mA·cm^(-2),desirable durability and methanol ***,the liquid ZAB established with Co-CoFe@NRPC-90 as an air-cathode electrocatalyst manifested an outstanding power density(281 mW·cm^(-2))and specific capacity(820.9 mAh·g_(Zn)^(-1)),transcending the liquid ZAB based on a commercial Pt/C electrocatalyst.

关键词： Fe/Co co-doped zeolitic imidazolium frameworks Graphitic carbon nitride Transition metal-nitrogen-carbon electrocatalyst Oxygen reduction reaction(ORR)

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In-situ measurement via the flow-through method and numerical simulations for radon exhalation during measurements of the radon exhalation rate

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Nuclear Science and Techniques 2024年第7期35卷 192-207页

作者： Ming xia Yong-Jun Ye Shan-Wei Shang ting Yu Dai-jia Chen School of Resources Environment and Safety Engineering University of South ChinaHengyang421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang421001China

Small-scale measurements of the radon exhalation rate using the flow-through and closed-loop methods were conducted on the surface of a uranium tailing pond to better understand the differences between the two *** abnormal radon exhalation behavior was observed,leading to computational fluid dynamics(CFD)-based simulations in which dynamic radon migration in a porous medium and accumulation chamber was *** on the in-situ experimental and numerical simulation results,variations in the radon exhalation rate subject to permeability,flow rate,and insertion depth were quantified and *** in-situ radon exhalation rates measured using the flow-through method were higher than those measured using the closed-loop method,which could be explained by the negative pressure difference between the inside and outside of the chamber during the *** consistency of the variations in the radon exhalation rate between the experiments and simulations suggests the reliability of CFD-based techniques in obtaining the dynamic evolution of transient radon exhalation rates for diffusion and convection at the porous medium-air *** synergistic effects of the three factors(insertion depth,flow rate,and permeability)on the negative pressure difference and measured exhalation rate were quantified,and multivariate regression models were established,with positive correlations in most cases;the exhalation rate decreased with increasing insertion depth at a permeability of 1×10^(−11) m^(2).CFD-based simulations can provide theoretical guidance for improving the flow-through method and thus achieve accurate measurements.

关键词： Radon exhalation Flow-through Numerical simulation Accumulation chamber Multivariate regression

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Androgen signaling inhibits de novo lipogenesis to alleviate lipid deposition in zebrafish

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Zoological Research 2024年第2期45卷 355-366页

作者： Jing-Yi jia Guang-Hui Chen ting-ting Shu Qi-Yong Lou xia Jin jiang-Yan He Wu-Han xiao Gang Zhai Zhan Yin College of Fisheries Huazhong Agriculture UniversityWuhanHubei 430070China State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhanHubei 430072China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China Hubei Key Laboratory of Three Gorges Project for Conservation of Fishes Chinese Sturgeon Research InstituteChina Three Gorges CorporationYichangHubei 443100China Hubei Hongshan Laboratory Huazhong Agriculture UniversityWuhanHubei 430070China Innovative Academy of Seed Design Chinese Academy of SciencesBeijing 100049China

Testosterone is closely associated with lipid metabolism and known to affect body fat composition and muscle mass in ***,the mechanisms by which testosterone acts on lipid metabolism are not yet fully understood,especially in *** this study,cyp17a1-/-zebrafish(Danio rerio)exhibited excessive visceral adipose tissue(VAT),lipid content,and up-regulated expression and activity of hepatic de novo lipogenesis(DNL)*** assay for transposase accessible chromatinwithsequencing(ATAC-seq)results demonstrated that chromatin accessibility of DNL genes was increased in cyp17a1-/-fish compared to cyp17a1+/+male fish,including stearoyl-CoA desaturase(scd)and fatty acid synthase(fasn).Androgen response element(ARE)motifs in the androgen signaling pathway were significantly enriched in cyp17a1+/+male fish but not in cyp17a1-/-*** androgen receptor(ar)-/-and wildtype(WT)zebrafish administered with Ar antagonist flutamide displayed excessive visceral adipose tissue,lipid content,and up-regulated expression and activity of hepatic de novo lipogenesis *** Ar agonist BMS-564929 reduced the content of VAT and lipid content,and down-regulated acetyl-CoA carboxylase a(acaca),fasn,and scd ***,the rescue effect of testosterone on cyp17a1-/-fish in terms of phenotypes was abolished when ar was additionally ***,these findings reveal that testosterone inhibits lipid deposition by down-regulating DNL genes via Ar in zebrafish,thus expanding our understanding of the relationship between testosterone and lipid metabolism in teleosts.

关键词： Cyp17a1 Testosterone Androgen receptor De novo lipogenesis Fatty acid synthesis

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A dynamical neural network approach for distributionally robust chance-constrained Markov decision process

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Science China Mathematics 2024年第6期67卷 1395-1418页

作者： Tian xia jia Liu Zhiping Chen School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049China

In this paper,we study the distributionally robust joint chance-constrained Markov decision *** the logarithmic transformation technique,we derive its deterministic reformulation with bi-convex terms under the moment-based uncertainty *** cope with the non-convexity and improve the robustness of the solution,we propose a dynamical neural network approach to solve the reformulated optimization *** results on a machine replacement problem demonstrate the efficiency of the proposed dynamical neural network approach when compared with the sequential convex approximation approach.

关键词： Markov decision process chance constraints distributionally robust optimization moment-based ambiguity set dynamical neural network

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Towards imbalanced motion:part-decoupling network for video portrait segmentation

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Science China(Information Sciences) 2024年第7期67卷 197-210页

作者： Tianshu YU Changqun xia jia LI State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang University Peng Cheng Laboratory

Video portrait segmentation(VPS), aiming at segmenting prominent foreground portraits from video frames, has received much attention in recent years. However, the simplicity of existing VPS datasets leads to a limitation on extensive research of the task. In this work, we propose a new intricate large-scale multi-scene video portrait segmentation dataset MVPS consisting of 101 video clips in 7 scenario categories,in which 10843 sampled frames are finely annotated at the pixel level. The dataset has diverse scenes and complicated background environments, which is the most complex dataset in VPS to our best *** the observation of a large number of videos with portraits during dataset construction, we find that due to the joint structure of the human body, the motion of portraits is part-associated, which leads to the different parts being relatively independent in motion. That is, the motion of different parts of the portraits is imbalanced. Towards this imbalance, an intuitive and reasonable idea is that different motion states in portraits can be better exploited by decoupling the portraits into parts. To achieve this, we propose a part-decoupling network(PDNet) for VPS. Specifically, an inter-frame part-discriminated attention(IPDA)module is proposed which unsupervisedly segments portrait into parts and utilizes different attentiveness on discriminative features specified to each different part. In this way, appropriate attention can be imposed on portrait parts with imbalanced motion to extract part-discriminated correlations, so that the portraits can be segmented more accurately. Experimental results demonstrate that our method achieves leading performance with the comparison to state-of-the-art methods.

关键词： video portrait segmentation imbalanced motion unsupervised part decoupling motion correlation inter-frame attention

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Structure attack on full-round DBST

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Frontiers of Computer Science 2024年第4期18卷 223-225页

作者： Chenhao jia Qing LING ting WU tingting CUI School of Cyberspace Hangzhou Dianzi UniversityHangzhou 310018China Hangzhou Innovation Institute Beihang UniversityHangzhou 310052China Key Laboratory of Cryptologic Technology and Information Security(Ministry of Education) Shandong UniversityQingdao 266237China

1 Introduction Block cipher is one of the most important part of symmetric cipher,which has been widely used in the field of computer communication and information system *** order to meet the increasing demand for ensuring secure data transmission in Internet of Things(IoT)environment,lightweight block ciphers have become more and more important due to their easy software implementation,low resource consumption,ease of standardization and high ***,in order to satisfy the constraints of resource-limited devices,lightweight block ciphers strive to achieve a balance between the cost of software and hardware implementation,efficiency,and ***,sometimes the security of lightweight block ciphers might be challenged due to the simplified ***,it is meaningful to study the type of simplified lightweight block ciphers.

关键词： hardware computer simplified

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Facile construction of Mxene-supported niobium hydride nanoparticles toward reversible hydrogen storage in magnesium borohydride

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Rare Metals 2024年第9期43卷 4387-4400页

作者： Ao xia jia-Guang Zheng Qing-Bo Zhang Yu-Gang Shu Cheng-Guo Yan Liu-ting Zhang Zhan-Liang Tao Li-Xin Chen School of Energy and Power Jiangsu University of Science and Technology Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai University State Key Laboratory of Silicon and Advanced Semiconductor Materials School of Materials Science and EngineeringZhejiang University

The facile construction of nanoscale NbHxsupported by Ti3C2（NbHx@Ti3C2） was achieved using facile ball milling strategy to improve the hydrogen desorption kinetics and reversibility of magnesium borohydride (Mg（BH4）2).The doping of 30 wt%NbHx@Ti3C2catalyst reduced the onset dehydrogenation temperature of Mg（BH4）2to 71.2℃.Additionally,the Mg（BH4）2+30NbHx@Ti3C2composite achieved remarkable hydrogen release of over 9.2 wt% at a temperature as low as 230℃,indicating unexpected dehydrogenation ***,the reversibility of NbHx@Ti3C2doped Mg（BH4）2was retained to more than 4.2 wt%after four cycles,which was increased by 68% compared to that of undoped Mg（BH4）*** strong catalysis of NbHx@Ti3C2catalyst could be attributed to the synergistic effect of NbHxand Ti3C2in hydrogen spillover and *** as a??hydrogen pump??for effective hydrogen spillover,while Ti3C2created numerous diffusion channels for hydrogen dissolution and provided the active catalytic site to facilitate the re/dehydrogenation of Mg（BH4）2.

关键词： Catalysts Hydrogen storage Magnesium borohydride Mxene

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Electrochemical CO_(2)reduction to C_(2+)products over Cu/Zn intermetallic catalysts synthesized by electrodeposition

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Frontiers in Energy 2024年第1期18卷 80-88页

作者： ting DENG Shuaiqiang jia Shitao HAN jianxin ZHAI jiapeng jiaO xiao CHEN Cheng XUE Xueqing XING Wei xia Haihong WU Mingyuan HE Buxing HAN School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200062China Institute of Eco-Chongming Shanghai 202162China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Institute of Chemistry Chinese Academy of SciencesBeijing 100190China

Electrocatalytic CO_(2)reduction(ECR)offers an attractive approach to realizing carbon neutrality and producing valuable chemicals and fuels using CO_(2)as the ***,the lack of cost-effective electrocatalysts with better performances has seriously hindered its ***,a one-step co-electrodeposition method was used to introduce Zn,a metal with weak^(*)CO binding energy,into Cu to form Cu/Zn intermetallic catalysts(Cu/Zn IMCs).It was shown that,using an H-cell,the high Faradaic efficiency of C_(2+)hydrocarbons/alcohols()could be achieved in ECR by adjusting the surface metal components and the applied *** suitable conditions,FEC_(2+)and current density could be as high as 75%and 40 mA/cm^(2),*** with the Cu catalyst,the Cu/Zn IMCs have a lower interfacial charge transfer resistance and a larger electrochemically active surface area(ECSA),which accelerate the ***,the^(*)CO formed on Zn sites can move to Cu sites due to its weak binding with*CO,and thus enhance the C–C coupling on the Cu surface to form C_(2+)products.

关键词： carbon dioxide electroreduction electrochemistry co-electrodeposition intermetallic catalysts value-added chemicals

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Effects of thawing-induced softening on fracture behaviors of frozen rock

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 979-989页

作者： ting Wang Hailiang jia Qiang Sun xianjun Tan Liyun Tang College of Geology and Environment Xi’an University of Science and TechnologyXi’an710054China College of Architecture and Civil Engineering Xi’an University of Science and TechnologyXi’an710054China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430064China

Due to the presence of ice and unfrozen water in pores of frozen rock,the rock fracture behaviors are susceptible to *** this study,the potential thawing-induced softening effects on the fracture behaviors of frozen rock is evaluated by testing the tension fracture toughness(KIC)of frozen rock at different temperatures(i.e.-20℃,-15℃,-12℃,-10℃,-8℃,-6℃,-4℃,-2℃,and 0℃).Acoustic emission(AE)and digital image correlation(DIC)methods are utilized to analyze the microcrack propagation during *** melting of pore ice is measured using nuclear magnetic resonance(NMR)*** results indicate that:(1)The KIC of frozen rock decreases moderately between-20℃ and-4℃,and rapidly between-4℃ and 0℃.(2)At-20℃ to-4℃,the fracturing process,deduced from the DIC results at the notch tip,exhibits three stages:elastic deformation,microcrack propagation and microcrack ***,at-4℃e0℃,only the latter two stages are observed.(3)At-4℃e0℃,the AE activities during fracturing are less than that at-20℃ to-4℃,while more small events are reported.(4)The NMR results demonstrate a reverse variation trend in pore ice content with increasing temperature,that is,a moderate decrease is followed by a sharp decrease and-4℃ is exactly the critical ***,we interpret the thawing-induced softening effect by linking the evolution in microscopic structure of frozen rock with its macroscopic fracture behaviors as follow:from-20℃ to-4℃,the thickening of the unfrozen water film diminishes the cementation strength between ice and rock skeleton,leading to the decrease in fracture ***-4℃ to 0℃,the cementation effect of ice almost vanishes,and the filling effect of pore ice is reduced significantly,which facilitates microcrack propagation and thus the easier fracture of frozen rocks.

关键词： Frozen sandstone Different thawing temperature Fracture toughness Microcrack propagation process Unfrozen water content

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Salivary metabolites are promising noninvasive biomarkers of druginduced liver injury

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World Journal of Gastroenterology 2024年第18期30卷 2454-2466页

作者： Si-Miao Yu Hao-Cheng Zheng Si-Ci Wang Wen-Ya Rong Ping Li Jing Jing ting-ting He jia-Hui Li xia Ding Rui-Lin Wang School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China School of Traditional Chinese Medicine Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Hepatology of Traditional Chinese Medicine The Fifth Medical Center of PLA General HospitalBeijing 100039China The First Clinical Medical College Henan University of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina

BACKGROUND Drug-induced liver injury(DILI)is one of the most common adverse events of medication use,and its incidence is ***,early detection of DILI is a crucial challenge due to a lack of biomarkers and noninvasive *** To identify salivary metabolic biomarkers of DILI for the future development of noninvasive diagnostic *** Saliva samples from 31 DILI patients and 35 healthy controls(HCs)were subjected to untargeted metabolomics using ultrahigh-pressure liquid chromatography coupled with tandem mass *** analyses,including partial least squares-discriminant analysis modeling,t tests and weighted metabolite coexpression network analysis(WMCNA),were conducted to identify key differentially expressed metabolites(DEMs)and metabolite *** we utilized least absolute shrinkage and selection operato and random fores analyses for biomarker *** use of each metabolite and metabolite set to detect DILI was evaluated with area under the receiver operating characteristic *** We found 247 differentially expressed salivary metabolites between the DILI group and the HC *** WMCNA,we identified a set of 8 DEMs closely related to liver injury for further prediction ***,the distinct separation of DILI patients and HCs was achieved with five metabolites,namely,12-hydroxydodecanoic acid,3-hydroxydecanoic acid,tetradecanedioic acid,hypoxanthine,and inosine(area under the curve:0.733-1).CONCLUSION Salivary metabolomics revealed previously unreported metabolic alterations and diagnostic biomarkers in the saliva of DILI *** study may provide a potentially feasible and noninvasive diagnostic method for DILI,but further validation is needed.

关键词： Drug-Induced liver injury Salivary Metabolomics Biomarker Weighted metabolite Coexpression network analysis Machine learning Noninvasive Diagnostic method Metabolites

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