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Linear paired electrolysis of furfural to furoic acid at both anode and cathode in a multiple redox mediated system
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作者 Xinxin Li Linchuan Cong +4 位作者 Haibo Lin Fangbing Liu Xiangxue Fu Hai-Chao Xu Nan Lin 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期104-113,共10页
Implementing a new energy-saving electrochemical synthesis system with high commercial value is a strategy of the sustainable development for upgrading the bulk chemicals preparation technology in the future.Here,we r... Implementing a new energy-saving electrochemical synthesis system with high commercial value is a strategy of the sustainable development for upgrading the bulk chemicals preparation technology in the future.Here,we report a multiple redox-mediated linear paired electrolysis system,combining the hydrogen peroxide mediated cathode process with the I2 mediated anode process,and realize the conversion of furfural to furoic acid in both side of the dividedflow cell simultaneously.By reasonably controlling the cathode potential,the undesired water splitting reaction and furfural reduction side reactions are avoided.Under the galvanostatic electrolysis,the two-mediated electrode processes have good compatibility,which reduce the energy consumption by about 22%while improving the electronic efficiency by about 125%.This system provides a green electrochemical synthesis route with commercial prospects. 展开更多
关键词 Multiple redox mediated system Linear paired electrolysis FURFURAL Furoic acid
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Covalent Bond Based Android Malware Detection Using Permission and System Call Pairs
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作者 Rahul Gupta Kapil Sharma R.K.Garg 《Computers, Materials & Continua》 SCIE EI 2024年第3期4283-4301,共19页
The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our lives.Their versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and... The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our lives.Their versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and access information.Among the many smartphones available,those operating on the Android platform dominate,being the most widely used type.This widespread adoption of the Android OS has significantly contributed to increased malware attacks targeting the Android ecosystem in recent years.Therefore,there is an urgent need to develop new methods for detecting Android malware.The literature contains numerous works related to Android malware detection.As far as our understanding extends,we are the first ones to identify dangerous combinations of permissions and system calls to uncover malicious behavior in Android applications.We introduce a novel methodology that pairs permissions and system calls to distinguish between benign and malicious samples.This approach combines the advantages of static and dynamic analysis,offering a more comprehensive understanding of an application’s behavior.We establish covalent bonds between permissions and system calls to assess their combined impact.We introduce a novel technique to determine these pairs’Covalent Bond Strength Score.Each pair is assigned two scores,one for malicious behavior and another for benign behavior.These scores serve as the basis for classifying applications as benign or malicious.By correlating permissions with system calls,the study enables a detailed examination of how an app utilizes its requested permissions,aiding in differentiating legitimate and potentially harmful actions.This comprehensive analysis provides a robust framework for Android malware detection,marking a significant contribution to the field.The results of our experiments demonstrate a remarkable overall accuracy of 97.5%,surpassing various state-of-the-art detection techniques proposed in the current literature. 展开更多
关键词 ANDROID MALWARE android security hybrid analysis permission and system call pairs
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Paired box proteins as diagnostic biomarkers for endocervical adenocarcinoma
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作者 Jia-Hui Zhou Xiang-Ning Zhang 《World Journal of Clinical Cases》 SCIE 2024年第26期5854-5858,共5页
In this editorial,we commented on the article by Akers et al published in the recent issue of the World Journal of Clinical Cases.We focused specifically on the role of the transcription factor paired box protein 8(PA... In this editorial,we commented on the article by Akers et al published in the recent issue of the World Journal of Clinical Cases.We focused specifically on the role of the transcription factor paired box protein 8(PAX8)belonging to the family PAX in the carcinogenesis of a gynecologic tumor,endocervical adenocarcinoma,arising from the tissue of mesonephric origin,and the potential diagnostic value for the same type of neoplasms.The global vaccination program of human papillomavirus(HPV)has dramatically reduced the incidence of cervical cancer,including cases of adenocarcinoma.The type of adenoid epithelial origin has a lower frequency of HPV detection but tends to be more aggressive and fatal.Cases of endocervical adenocarcinoma occurring in females of menopause age have been described in the 2023 volume of the World Journal of Clinical Cases and in our study recently published in Oncol Lett.The histopathological findings and immunohistochemical assays showed that the lesions had glandular morphology,and the specimens in these two reports were immunohistochemically positive for the transcription factor PAX8,albeit that they had opposing expression profiles of tumor suppressor p16 and estrogen receptor and the presence of the HPV genome.The presence of a mucin protein,MUC 5AC,as revealed in both studies suggested target molecules for the diagnosis of mucinous adenoid type of uterine tumor and other histological origins.The clinical outcome was unfavorable due to metastasis and recurrence.This prompted the improvement of the antitumor modality,with the introduction of precise targeting therapy.Mucin has now been reported to be the therapeutic target for adenocarcinomas. 展开更多
关键词 Cervical adenocarcinoma Diagnostic biomarker paired box protein 8 EMBRYOGENESIS Transcription factor
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Paired Assistance:Policy Rationale and Economic Performance as Illustrated by Xizang and Xinjiang
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作者 Li Xihui Wang Guiduo +1 位作者 Duan Pengfei Huang Jixin 《China Economist》 2024年第3期70-88,共19页
This study highlights the changing priorities of China’s paired assistance throughout the past decades,as well as its theoretical implications and economic growth effects for recipient regions.Using panel data from 3... This study highlights the changing priorities of China’s paired assistance throughout the past decades,as well as its theoretical implications and economic growth effects for recipient regions.Using panel data from 32 prefecture-level cities from 1990 to 2020,this study uses the multiperiod difference-in-differences approach to examine how paired assistance has contributed to economic growth in Xizang Autonomous Region and Xinjiang Uygur Autonomous Region.The findings indicate that,first,the implementation of the paired assistance policy has boosted economic growth in Xizang and Xinjiang.Second,paired assistance has stimulated economic growth in recipient communities by improving infrastructure.Third,paired assistance has contributed to economic growth in recipient communities by providing improved public services such as education and healthcare.Improvements to public services have a relatively smaller indirect effect in short term than infrastructure development on economic growth.Yet both education and healthcare are crucial to people’s quality of life in recipient communities.This paper has refined and broadened research on the effects of paired assistance,providing preference for future policymaking. 展开更多
关键词 Chinese characteristics paired assistance multiperiod difference-in-differences assessment of policy effects
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Long-term trends in the abundance and breeding performance in Adélie penguins:the Argentine Ecosystem Monitoring Program
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作者 Mariana A.JUÁRES AnahíM.SILVESTRO +1 位作者 Brenda C.ALFONSO M.Mercedes SANTOS 《Advances in Polar Science》 CSCD 2024年第1期132-140,共9页
In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Poin... In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point. 展开更多
关键词 long-term monitoring Adélie penguin breeding pairs chicks crèched breeding success population trends
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Late Neoarchean crustal growth under paired continental arc-back arc system in the North China Craton 被引量:2
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作者 Xin He Wei Wang +5 位作者 M.Santosh Jiachen Yao Kangting Gao Yuhan Zhang Denggang Lu Lishuang Guo 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第3期437-457,共21页
The late Archean(~3.0-2.5 Ga)was a key period of continental growth globally,which is widely considered to reflect the onset of vigorous plate tectonic activity,although related continental growth modes remain content... The late Archean(~3.0-2.5 Ga)was a key period of continental growth globally,which is widely considered to reflect the onset of vigorous plate tectonic activity,although related continental growth modes remain contentious.Here we investigate a suite of late Neoarchean metavolcanic rocks from the southwest Qixia area of the Jiaobei terrane in the North China Craton.The rocks in this suite include amphibolites,clinopyroxene amphibolites,and hornblende plagioclase gneisses.We present zircon U-Pb isotopic data which indicate that the protoliths of these rocks formed during~2549-2511 Ma.The(clinopyroxene)amphibolites correspond to meta-basaltic rocks,with some containing high modal content of titanite.These rocks show moderate to high FeO_(T)(8.96-13.62 wt.%)and TiO_(2)(0.59-1.59 wt.%),flat to less fractionated REE patterns,and mildly negative Th,Nb,and Ta anomalies,resembling those of Fe-tholeiites.In addition,they display positive zirconε_(Hf)(t)values(+2.6 to+8.7),and are devoid of crustal contamination or fractional crystallization.Combined with the low Nb/Yb(mostly<1.60)and(Hf/Sm)_N(mostly<0.95),low to moderate Th/Yb(0.08-0.54),and low V/Sc(5.53-9.19)ratios,these basaltic rocks are interpreted to have been derived from a relatively reduced and depleted mantle source that was mildly metasomatized by hydrous fluids.The hornblende plagioclase gneisses are meta-andesitic rocks,and occur interlayered with the basaltic rocks.They are transitional between tholeiitic and calc-alkaline rock series,and show fractionated REE patterns with evidently negative Th,Nb,and Ta anomalies.The depleted zirconε_(Hf)(t)values(+2.4 to+8.4)and quantitative chemical modeling suggest that the andesitic rocks were most likely generated by injection and mixing of juvenile felsic magmas with the tholeiitic basaltic magmas.In general,the chemical features and genesis of late Neoarchean meta-basaltic rocks in our study area resemble those of Mariana back-arc basin basalts.Combined with regional geological data,it is proposed that the Jiaobei terrane witnessed late Neoarchean crustal growth under a paired continental arc-back arc setting.On a regional context,we propose two distinct geodynamic mode of late Neoarchean continental growth across North China Craton(particularly the Eastern Block),i.e.,(1)arc-continent accretion along northwestern part of the Eastern Block;and(2)paired continental arc-back arc system surrounding the~3.8-2.7 Ga continental nuclei to the southeast. 展开更多
关键词 Late Neoarchean metavolcanic rocks Continental growth paired continental arc-back arc Jiaobei terrane North China Craton
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Distribution of paired immunoglobulin-like receptor B in the nervous system related to regeneration difficulties after unilateral lumbar spinal cord injury 被引量:3
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作者 Wan-shu Peng Chao Qi +4 位作者 Hong Zhang Mei-ling Gao Hong Wang Fei Ren Xia-qing Li 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第7期1139-1146,共8页
Paired immunoglobulin-like receptor B(Pir B) is a functional receptor of myelin-associated inhibitors for axonal regeneration and synaptic plasticity in the central nervous system, and thus suppresses nerve regenera... Paired immunoglobulin-like receptor B(Pir B) is a functional receptor of myelin-associated inhibitors for axonal regeneration and synaptic plasticity in the central nervous system, and thus suppresses nerve regeneration. The regulatory effect of Pir B on injured nerves has received a lot of attention. To better understand nerve regeneration inability after spinal cord injury, this study aimed to investigate the distribution of Pir B(via immunofluorescence) in the central nervous system and peripheral nervous system 10 days after injury. Immunoreactivity for Pir B increased in the dorsal root ganglia, sciatic nerves, and spinal cord segments. In the dorsal root ganglia and sciatic nerves, Pir B was mainly distributed along neuronal and axonal membranes. Pir B was found to exhibit a diffuse, intricate distribution in the dorsal and ventral regions. Immunoreactivity for Pir B was enhanced in some cortical neurons located in the bilateral precentral gyri. Overall, the findings suggest a pattern of Pir B immunoreactivity in the nervous system after unilateral spinal transection injury, and also indicate that Pir B may suppress repair after injury. 展开更多
关键词 nerve regeneration paired immunoglobulin-like receptor B myelin inhibitory factor spinal cord injury peripheral nervous system central nervous system cerebral cortex dorsal root ganglion neural regeneration
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Paired regions for shadow removal approach based on multi-features
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作者 张之政 GUO Mingqiang +2 位作者 WU Liang HUANG Ying CHEN Xueye 《High Technology Letters》 EI CAS 2023年第2期174-180,共7页
The existence of shadow leads to the degradation of the image qualities and the defect of ground object information.Shadow removal is therefore an essential research topic in image processing filed.The biggest challen... The existence of shadow leads to the degradation of the image qualities and the defect of ground object information.Shadow removal is therefore an essential research topic in image processing filed.The biggest challenge of shadow removal is how to restore the content of shadow areas correctly while removing the shadow in the image.Paired regions for shadow removal approach based on multi-features is proposed, in which shadow removal is only performed on related sunlit areas.Feature distance between regions is calculated to find the optimal paired regions with considering of multi-features(texture, gradient feature, etc.) comprehensively.Images in different scenes with peak signal-to-noise ratio(PSNR) and structural similarity(SSIM) evaluation indexes are chosen for experiments.The results are shown with six existing comparison methods by visual and quantitative assessments, which verified that the proposed method shows excellent shadow removal effect, the brightness, color of the removed shadow area, and the surrounding non-shadow area can be naturally fused. 展开更多
关键词 paired region feature distance TEXTURE peak signal-to-noise ratio(PSNR) structural similarity(SSIM)
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Estimating Evapotranspiration Using Chloride Mass Balance in a New Mexico Paired Basin Study 2009-2019
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作者 Amy C. Lewis Daniel Cadol 《Journal of Water Resource and Protection》 CAS 2023年第4期115-129,共15页
A paired basin study in the upper Santa Fe River watershed following forest thinning and prescribed burns successfully measured water budget components in a treated and an untreated (control) basin. The paired basin s... A paired basin study in the upper Santa Fe River watershed following forest thinning and prescribed burns successfully measured water budget components in a treated and an untreated (control) basin. The paired basin study was established to investigate questions that have arisen regarding changes in water yield from forest treatments. Precipitation, stream flow, soil moisture, and chloride concentrations in precipitation and stream flow were measured to quantify the water budget components. The results from eleven years of data collection and analysis have a high degree of confidence with respect to measuring the water budget components based on the mass balance of water and chloride. The differences in the geologic structure and topography between the two paired basins appeared to impact the water budgets more than the forest treatments, except during periods when winter precipitation and snowmelt represented a significant component of inflow. Although this paired basin study was not able to portray a simple relationship between forest thinning and water yield, the chloride concentration methodology used to estimate evapotranspiration (ET) was successful. These detailed observations of chloride deposition and transport characteristics may be relevant for other researchers working in forested basins with substantial ET. ET rates were estimated by examining the cycle of chloride entering and exiting each basin over six integration periods. ET was estimated to be about 90% to 94% of precipitation in the treated basin and 77% to 86% in the control basin. The higher ET in the treated basin both before and after forest treatments may be due to the much greater area of west-facing hillslopes in the treated basin, which receive warm afternoon sun, and the greater area of rock cover in the control basin. Variation in the chloride concentration of collected precipitation samples from different sites indicates that horizontal precipitation of chloride in the tree canopy is an important consideration when using the chloride mass balance approach to calculate water budget components. 展开更多
关键词 EVAPOTRANSPIRATION Chloride Mass Balance paired Basins Water Budgets Horizontal Precipitation
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Network pharmacology and subsequent experimental validation reveal the synergistic myocardial protection mechanism of Salvia miltiorrhiza Bge.and Carthamus tinctorius L. 被引量:1
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作者 Linying Zhong Ling Dong +7 位作者 Jing Sun Jie Yang Zhiying Yu Ping He Bo Zhu Yuxin Zhu Siyuan Li Wenjuan Xu 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期44-54,共11页
Objective:To reveal the molecular mechanism underlying the compatibility of Salvia miltiorrhiza Bge(S.miltiorrhiza,Dan Shen)and C.tinctorius L.(C.tinctorius,Hong Hua)as an herb pair through network pharmacology and su... Objective:To reveal the molecular mechanism underlying the compatibility of Salvia miltiorrhiza Bge(S.miltiorrhiza,Dan Shen)and C.tinctorius L.(C.tinctorius,Hong Hua)as an herb pair through network pharmacology and subsequent experimental validation.Methods:Network pharmacology was applied to construct an active ingredient-efficacy target-disease protein network to reveal the unique regulation pattern of s.miltiorrhiza and C.tinctorius as herb pair.Molecular docking was used to verify the binding of the components of these herbs and their potential targets.An H9c2 glucose hypoxia model was used to evaluate the efficacy of the components and their synergistic effects,which were evaluated using the combination index.Western blot was performed to detect the protein expression of these targets.Results:Network pharmacology analysis revealed 5 pathways and 8 core targets of s.miltiorrhiza and C.tinctorius in myocardial protection.Five of the core targets were enriched in the hypoxia-inducible factor-1(HIF-1)signaling pathway.S.miltiorrhiza-C.tinctorius achieved vascular tone mainly by regulating the target genes of the HIF-1 pathway.As an upstream gene of the HIF-1 pathway,STAT3 can be activated by the active ingredients cryptotanshinone(Ctan),salvianolic acid B(Sal.B),and myricetin(Myric).Cell experiments revealed that Myric,Sal.B,and Ctan also exhibited synergistic myocardial protective activity.Molecular docking verified the strong binding of Myric,Sal.B,and Ctan to STAT3.Western blot further showed that the active ingredients synergistically upregulated the protein expressionof STAT3.Conclusion:The pharmacodynamic transmission analysis revealed that the active ingredients of S.miltiorrhiza and C.tinctorius can synergistically resist ischemia through various targets and pathways.This study provides a methodological reference for interpreting traditional Chinese medicine compatibility. 展开更多
关键词 S.miltiorrhiza-C.tinctorius herb pair Compatibilitymechanism Networkpharmacology Multipletargeteffect Myocardial protection
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基于ConvMixer架构的高效点云分类方法
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作者 王淳 赵艳明 冯燕 《中国传媒大学学报(自然科学版)》 2024年第1期56-64,共9页
近年来,视觉Transformer模型在点云分类等三维计算机视觉任务中显现出潜在的优越性,但其有效性来源仍然模糊不清。研究它们在视觉任务中的性能是完全归功于Transformer结构本身的优越性,还是至少部分得益于使用局部块作为输入表示,是非... 近年来,视觉Transformer模型在点云分类等三维计算机视觉任务中显现出潜在的优越性,但其有效性来源仍然模糊不清。研究它们在视觉任务中的性能是完全归功于Transformer结构本身的优越性,还是至少部分得益于使用局部块作为输入表示,是非常必要的。受此启发,本文提出了一种简单但仍然有效的点云分类和分割模型PointConvMixer,用ConvMixer架构取代了Point-BERT中的标准Transformer。PointConvMixer在ModelNet40数据集上的整体分类准确率达到92.3%,在ShapeNet Parts数据集上进行点云部分分割时mIOUI和mIOUC分别为85.4%和83.9%,均优于基于Transformer的对比模型。此外,本文还进一步提出PPFConvMixer,其利用高效的局部特征描述符PPF增强了PointConvMixer,从而优化了点云分类性能。在查询半径为0.25m时,PPFConvMixer的总体分类准确率达到了93.8%。 展开更多
关键词 三维点云分类 深度学习 ConvMixer Point Pair Feature
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Pairing correlation of the kagome-lattice Hubbard model with the nearest-neighbor interaction
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作者 Chen Yang Chao Chen +2 位作者 Runyu Ma Ying Liang Tianxing Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期41-45,共5页
A recently discovered family of kagome lattice materials,AV_(3)Sb_(5)(A=K,Rb,Cs),has attracted great interest,especiallyin the debate over their dominant superconducting pairing symmetry.To explore this issue,we study... A recently discovered family of kagome lattice materials,AV_(3)Sb_(5)(A=K,Rb,Cs),has attracted great interest,especiallyin the debate over their dominant superconducting pairing symmetry.To explore this issue,we study the superconductingpairing behavior within the kagome-lattice Hubbard model through the constrained path Monte Carlo method.It isfound that doping around the Dirac point generates a dominant next-nearest-neighbor-d pairing symmetry driven by on-siteCoulomb interaction U.However,when considering the nearest-neighbor interaction V,it may induce nearest-neighbor-ppairing to become the preferred pairing symmetry.Our results provide useful information to identify the dominant superconductingpairing symmetry in the AV_(3)Sb_(5)family. 展开更多
关键词 kagome-lattice Hubbard model SUPERCONDUCTIVITY pairing symmetry CPMC
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Effects of carrier density and interactions on pairing symmetry in a t_(2g) model
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作者 李云霄 西文翰 +3 位作者 董召阳 姚子健 于顺利 李建新 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期223-230,共8页
By utilizing the fluctuation exchange approximation method,we perform a study on the superconducting pairing symmetry in a t_(2g) three-orbital model on the square lattice.Although the tight-binding parameters of the ... By utilizing the fluctuation exchange approximation method,we perform a study on the superconducting pairing symmetry in a t_(2g) three-orbital model on the square lattice.Although the tight-binding parameters of the model are based on Sr_(2)RuO_(4),we have systematically studied the evolution of superconducting pairing symmetry with the carrier density and interactions,making our findings relevant to a broader range of material systems.Under a moderate Hund’s coupling,we find that spin fluctuations dominate the superconducting pairing,leading to a prevalent spin-singlet pairing with a d_(x^(2)-y^(2))-wave symmetry for the carrier density within the range of n=1.5-4 per site.By reducing the Hund’s coupling,the charge fluctuations are enhanced and play a crucial role in determining the pairing symmetry,leading to a transition of the pairing symmetry from the spin-singlet d_(x^(2)-y^(2))-wave to the spin-triplet p-wave.Furthermore,we find that the superconducting pairings are orbital dependent.As the carrier density changes from n=4 to n=1.5,the active orbitals for superconducting pairing shift from the quasi-two-dimensional orbital dxy to the quasi-one-dimensional orbitals d_(xz) and d_(yz). 展开更多
关键词 unconventional superconductivity pairing mechanism Fermi surface three-orbital model
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Normal and Superconducting Properties of La_(3)Ni_(2)O_(7)
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作者 王猛 闻海虎 +2 位作者 吴涛 姚道新 向涛 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第7期140-151,共12页
This review provides a comprehensive overview of current research on the structural,electronic,and magnetic characteristics of the recently discovered high-temperature superconductor La_(3)Ni_(2)O_(7) under high press... This review provides a comprehensive overview of current research on the structural,electronic,and magnetic characteristics of the recently discovered high-temperature superconductor La_(3)Ni_(2)O_(7) under high pressures.We present the experimental results for synthesizing and characterizing this material,derived from measurements of transport,thermodynamics,and various spectroscopic techniques,and discuss their physical implications.We also explore theoretical models proposed to describe the electronic structures and superconducting pairing symmetry in La_(3)Ni_(2)O_(7),highlighting the intricate interplay between electronic correlations and magnetic interactions.Despite these advances,challenges remain in growing high-quality samples free of extrinsic phases and oxygen deficiencies and in developing reliable measurement tools for determining diamagnetism and other physical quantities under high pressures.Further investigations in these areas are essential to deepening our understanding of the physical properties of La_(3)Ni_(2)O_(7) and unlocking its superconducting pairing mechanism. 展开更多
关键词 PAIRING ELECTRONIC DEEPENING
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Boosting Electrochemical Urea Synthesis via Constructing Ordered Pd–Zn Active Pair
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作者 Weiliang Zhou Chao Feng +12 位作者 Xuan Li Xingxing Jiang Lingyan Jing Shuai Qi Qihua Huo Miaoyuan Lv Xinbao Chen Tianchi Huang Jingwen Zhao Na Meng Hengpan Yang Qi Hu Chuanxin He 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期529-540,共12页
Electrochemical co-reduction of nitrate(NO_(3)^(-))and carbon dioxide(CO_(2))has been widely regarded as a promising route to produce urea under ambient conditions,however the yield rate of urea has remained limited.H... Electrochemical co-reduction of nitrate(NO_(3)^(-))and carbon dioxide(CO_(2))has been widely regarded as a promising route to produce urea under ambient conditions,however the yield rate of urea has remained limited.Here,we report an atomically ordered intermetallic pallium-zinc(PdZn)electrocatalyst comprising a high density of PdZn pairs for boosting urea electrosynthesis.It is found that Pd and Zn are responsible for the adsorption and activation of NO_(3)^(-)and CO_(2),respectively,and thus the co-adsorption and co-activation NO_(3)^(-)and CO_(2) are achieved in ordered PdZn pairs.More importantly,the ordered and well-defined PdZn pairs provide a dual-site geometric structure conducive to the key C-N coupling with a low kinetical barrier,as demonstrated on both operando measurements and theoretical calculations.Consequently,the PdZn electrocatalyst displays excellent performance for the co-reduction to generate urea with a maximum urea Faradaic efficiency of 62.78%and a urea yield rate of 1274.42μg mg^(-1) h^(-1),and the latter is 1.5-fold larger than disordered pairs in PdZn alloys.This work paves new pathways to boost urea electrosynthesis via constructing ordered dual-metal pairs. 展开更多
关键词 Electrochemical C-N coupling Urea electrosynthesis Intermetallic compounds Geometric structures Active pairs
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Spin-polarized pairing induced by the magnetic field in the Bernal bilayer graphene
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作者 黄妍 周涛 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期650-654,共5页
Recent experimental findings have demonstrated the occurrence of superconductivity in Bernal bilayer graphene when induced by a magnetic field.In this study,we conduct a theoretical investigation of the potential pair... Recent experimental findings have demonstrated the occurrence of superconductivity in Bernal bilayer graphene when induced by a magnetic field.In this study,we conduct a theoretical investigation of the potential pairing symmetry within this superconducting system.By developing a theoretical model,we primarily calculate the free energy of the system with p+ip-wave parallel spin pairing,p+ip-wave anti-parallel spin pairing and d+i d-wave pairing symmetry.Our results confirm that the magnetic field is indeed essential for generating the superconductivity.We discover that the p+ip-wave parallel spin pairing leads to a lower free energy for the system.The numerical calculations of the energy band structure,zero-energy spectral function and density of states for each of the three pairing symmetries under consideration show a strong consistency with the free energy results. 展开更多
关键词 SUPERCONDUCTIVITY magnetic field induction pairing symmetry Bernal bilayer graphene
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Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory
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作者 Yang Su Ze-Yu Li +3 位作者 Li-Le Liu Guo-Xiang Dong Xiao-Bao Wang Yong-Jing Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期198-207,共10页
Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pair... Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data. 展开更多
关键词 Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution
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Atomic Dispersed Hetero‑Pairs for Enhanced Electrocatalytic CO_(2)Reduction
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作者 Zhaoyong Jin Meiqi Yang +13 位作者 Yilong Dong Xingcheng Ma Ying Wang Jiandong Wu Jinchang Fan Dewen Wang Rongshen Xi Xiao Zhao Tianyi Xu Jingxiang Zhao Lei Zhang David J.Singh Weitao Zheng Xiaoqiang Cui 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期55-67,共13页
Electrochemical carbon dioxide reduction reaction(CO_(2)RR)involves a variety of intermediates with highly correlated reaction and ad-desorption energies,hindering optimization of the catalytic activity.For example,in... Electrochemical carbon dioxide reduction reaction(CO_(2)RR)involves a variety of intermediates with highly correlated reaction and ad-desorption energies,hindering optimization of the catalytic activity.For example,increasing the binding of the*COOH to the active site will generally increase the*CO desorption energy.Breaking this relationship may be expected to dramatically improve the intrinsic activity of CO_(2)RR,but remains an unsolved challenge.Herein,we addressed this conundrum by constructing a unique atomic dispersed hetero-pair consisting of Mo-Fe di-atoms anchored on N-doped carbon carrier.This system shows an unprecedented CO_(2)RR intrinsic activity with TOF of 3336 h−1,high selectivity toward CO production,Faradaic efficiency of 95.96%at−0.60 V and excellent stability.Theoretical calculations show that the Mo-Fe diatomic sites increased the*COOH intermediate adsorption energy by bridging adsorption of*COOH intermediates.At the same time,d-d orbital coupling in the Mo-Fe di-atom results in electron delocalization and facilitates desorption of*CO intermediates.Thus,the undesirable correlation between these steps is broken.This work provides a promising approach,specifically the use of di-atoms,for breaking unfavorable relationships based on understanding of the catalytic mechanisms at the atomic scale. 展开更多
关键词 CO_(2)reduction reaction Atomic dispersed catalyst Hetero-diatomic pair Ad-desorption energy Linear scaling relation
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Highlighting relationships between sand thicknesses,reservoir-seal pairs and paleobathymetry from a sequence stratigraphic perspective:An example from Tortonian Serravallian deposits,onshore Niger Delta Basin
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作者 Ifeanyichukwu S.Obi K.Mosto Onuoha Chidozie I.Princeton Dim 《Energy Geoscience》 EI 2024年第1期12-23,共12页
The utilization of sequence stratigraphic concepts in identifying sands and their spatial continuity in distinct gross depositional settings is key,especially in frontier settings where data paucity is a common challe... The utilization of sequence stratigraphic concepts in identifying sands and their spatial continuity in distinct gross depositional settings is key,especially in frontier settings where data paucity is a common challenge.In the Baka field,onshore Niger Delta,detailed reservoir correlation guided by sequence stratigraphic framework analysis showed the distribution of sand and shale units constituting reservoirseal pairs(RSP)correlatable across the field.Within the 3rd-order packages,it is observed that the lowstand systems tract(LST)and highstand systems tract(HST)contain more RSPs and thicker 4th-and 5th-order sands than the transgressive systems tract(TST).In terms of bathymetry,it is noted that irrespective of systems tracts,the RSP Index(RI)decreases from the proximal shallow/inner shelf settings to the more distal outer shelf areas.Amongst all three systems tracts,intervals interpreted as lowstand prograding complexes contain the best developed sands and highest RSP.Sand development within the LSTs has been controlled by a pronounced growth fault regime accompanied by high subsidence and sedimentation rates.This is linked to the basinward migration of the sands during prolonged sea-level fall,creating significant accommodation space for sand deposition.On the other hand,the TSTs known to mark periods of progressive sea-level rise and landward migration of sandy facies,show thinner sands enclosed in much thicker,laterally extensive,and better-preserved deeper marine shales.Interpreted seismic sections indicate intense growth faulting and channelization that influenced the syn-and postdepositional development of the sand packages across the field.The initial timing of deformation of subregional faults in this area coincides with periods of abrupt falls in sea level.This approach could be useful for predicting sand-prone areas in frontier fields as well as possible reservoir-seal parameters required for some aspects of petroleum system analysis and quick-look volume estimation. 展开更多
关键词 Reservoir-seal pairs(RSP) systems tract Coastal swamp depobelt Bathymetry Sequence stratigraphy Niger Delta Basin
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Effect of the mixing of s-wave and chiral p-wave pairings on electrical shot noise properties of normal metal/superconductor tunnel junctions
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作者 胡雨辰 胡梁宾 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期538-545,共8页
We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion ... We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion symmetry. We investigate how the shot noise properties vary as the relative amplitude between the two parity components in the pairing potential is changed. It is demonstrated that some characteristics of the electrical shot noise properties of such tunnel junctions may depend sensitively on the relative amplitude between the two parity components in the pairing potential, and some significant changes may occur in the electrical shot noise properties when the relative amplitude between the two parity components is varied from the singlet s-wave pairing dominated regime to the chiral triplet p-wave pairing dominated regime. In the chiral triplet p-wave pairing dominated regime, the ratio of noise power to electric current is close to 2e both in the in-gap and in the out-gap region. In the singlet s-wave pairing dominated regime, the value of this ratio is close to 4e in the inner gap region but may reduce to about 2e in the outer gap region as the relative amplitude of the chiral triplet pairing component is increased. The variations of the differential shot noise with the bias voltage also exhibit some significantly different features in different regimes. Such different features can serve as useful diagnostic tools for the determination of the relative magnitude of the two parity components in the pairing potential. 展开更多
关键词 normal metal/superconductor tunnel junctions shot noise mixing of s-wave and chiral p-wave pairing spin–orbit coupling
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