The practical application of lithium–sulfur(Li–S)batteries is limited by the easy dissolution of polysulfides in the electrolyte,resulting in the lithium polysulfide(LPS)shuttle effect.Several two-dimensional(2D)mat...The practical application of lithium–sulfur(Li–S)batteries is limited by the easy dissolution of polysulfides in the electrolyte,resulting in the lithium polysulfide(LPS)shuttle effect.Several two-dimensional(2D)materials with abundant active binding sites and high surface-to-volume ratios have been developed to prepare functional separators that suppress the diffusion of polysulfides.However,the influence of modified layer thickness on Li+transport has not been considered.Herein,we synthesized individual and multilayered 2D Ti3C2Tx MXene nanosheets and used them to fabricate a series of Ti3C2Tx-PP modified separators.The separators had mass loadings ranging from 0.16 to 0.016 mg cm-2,which is the lowest value reported for 2D materials to the best of our knowledge.The corresponding reductions in thickness ranged from 1.2μm to 100 nm.LPS shuttling was effectively suppressed,even at the lowest mass loading of 0.016 mg cm-2.Suppression was due to the strong interaction between LPS intermediates and Ti atoms and hydroxyl functional groups on the separator surface.The lithium-ion diffusion coefficient increased with the reduction of Ti3C2Tx layers on the separator.Superior cycling stability and rate performance were attained when the separator with a Ti3C2Tx-PP mass loading of 0.016 mg cm-2 was incorporated into a Li–S battery.Carbon nanotubes(CNTs)were introduced into the separators to further improve the electrical and Li+ionic conductivity in the cross-plane direction of the 2D Ti3C2Txlayers.With the ultralightweight Ti3C2Tx/CNTs modified PP separator,the cell maintained a capacity of 640 m Ah g-1after 200cycles at 1C with a capacity decay of only 0.079%per cycle.展开更多
In this contribution we use VMS mineral systems in the Bryah rift-basin to constrain the tectonic setting of the widespread mafic and ultramafic magmatism that characterises the rift-basin in question.Two distinct,but...In this contribution we use VMS mineral systems in the Bryah rift-basin to constrain the tectonic setting of the widespread mafic and ultramafic magmatism that characterises the rift-basin in question.Two distinct,but temporally closely associated,lithostratigraphic sequences,Narracoota and Karalundi Formations,are discussed.The Karalundi Formation is the main host of VMS mineral systems in the region.The Karalundi Formation consists of turbiditic and immature clastic sediments,which are locally intercalated with basaltic hyaloclastites,dolerites and banded jaspilites.We propose that the basaltic hyaloclastites,dolerites and elastics and jaspilites rocks,form a distinct unit of the Karalundi Formation,named Noonyereena Member.The VMS mineral systems occur near the north-east trendingJenkin Fault and comprise the giant and world-class DeCrussa and the Red Bore deposits.The nature of these deposits and their intimate association with terrigenous clastic rocks and dominantly marine mafic volcanic and subvolcanic rocks,as well as the common development of peperitic margins,are considered indicative of a Besshi-type environment,similar to that of present-day Gulf of California.Our Re-Os age data from a primary pyrite yielded a mean model age of 2012 ± 48 Ma,which coincides（within error） with recent published Re-Os data（Hawke et al.,2015） and confirms the timing of the proposed geodynamic evolution.We propose a geodynamic model that attempts to explain the presence of the Narracoota and Karalundi Formations as the result of mantle plume activity,which began with early uplift of continental crust with intraplate volcanism,followed by early stages of rifting with the deposition of the Karalundi Formation（and Noonyereena Member）,which led to the formation of Besshi-type VMS deposits.With on-going mantle plume activity and early stages of continental separation,an oceanic plateau was formed and is now represented by mafic-ultramafic rocks of the Narracoota Formation.展开更多
Objective:To explore the expression of IL-2 and IL-11 and its significance in patients with ankylosing spondylitis(AS).Methods:A total of 48 active AS patients in our hospital and 40 normal control subjects were selec...Objective:To explore the expression of IL-2 and IL-11 and its significance in patients with ankylosing spondylitis(AS).Methods:A total of 48 active AS patients in our hospital and 40 normal control subjects were selected in our study.Bath ankylosing spondylitis disease activity index(BASDAI),Bath ankylosing spondylitis functional index(BASFI),Bath ankylosing spondylitis metrology index(BASMI),ESR and CRP expression levels were compared before treatment,12 h after treatment and 24 h after treatment.IL-2 and IL-11 expression were also compared between these two groups.Results:The BASDAI score,BASH score and BASMI score of the AS patients before treatment significantly decreased compared with those 12 weeks and 24 weeks after treatment(P【0.05).ESB and CRP levels of the AS patients 12 weeks and 24 weeks after treatment significantly decreased compared with those before treatment(P【0.05).Difference was significant in serum IL-2 and IL-11 levels between 12 weeks and 24 weeks after treatment and before treatment(P【0.05).And no statistically significance was observed for serum IL-2 and IL-11 levels between normal control group and those of patients in AS group 24 weeks after treatment(P】0.05). Pearson’s linear-correlation analysis showed that serum IL-2 level had a positive correlation with BASDAI,BASFI,BASMI,ESR and CRP(r=0.661.0.547,0.474,0.362,0.416,P【0.05) and serum IL-11 level had a negative correlation with BASDAI,BASFI,BASMI,ESR and CRP(r=-0.629, -0.412,-0.422,-0.387,-0.408,-0.315,P【0.05).Conclusions:Serum levels of IL-2 in active AS patients significantly increase and will decrease after treatment.However,serum levels of IL- 11 significantly decrease and will increase after treatment,which indicates that serum IL-2 has a positive correlation with the degree of AS and serum IL-11 has a negative correlation with the degree of AS,both of which are correlated closely with the onset of AS.展开更多
1.Objective In the past decade,a group of medium to giant lead-zinc deposits,represented by Huoshaoyun,Sachakou,and Yuanbaoling,have been discovered in the Aksai Chin region of Karakoram,Xinjiang.They are all located ...1.Objective In the past decade,a group of medium to giant lead-zinc deposits,represented by Huoshaoyun,Sachakou,and Yuanbaoling,have been discovered in the Aksai Chin region of Karakoram,Xinjiang.They are all located in the Mesozoic carbonate and clastic rock formations.The Sachakou leadzinc mining area is adjacent to the northwest of the Huoshaoyun lead-zinc mining area and is in the same stratigraphic layer as Huoshaoyun.Although many scholars have been arguing about the type and age of Huoshaoyun lead-zinc mineralization,few scholars have paid attention to the classification of the ore-bearing strata in the area.The stratigraphy of the Lower Permian Shenxianwan Group to the Upper Cretaceous Tielongtan Group is exposed in the Sachakou area of Karakorum,Xinjiang,however,the Late Permian-Early Triassic stratigraphy is missing(Fig.1a).Due to the harsh natural conditions in the area and the low level of work,the stratigraphic delineation is not exhaustive,and the regional lithology is dominated by carbonates and clastic rocks,which makes it difficult to identify the age of the regional lithology and causes problems for the exploration and research of lead-zinc in the area.展开更多
Nickel oxide(NiOx)has exhibited great potential as an inorganic hole transport layer(HTL)in perovskite solar cells(PSCs)due to its wide optical bandgap and superior stability.In this study,we have modulated the Ni26 v...Nickel oxide(NiOx)has exhibited great potential as an inorganic hole transport layer(HTL)in perovskite solar cells(PSCs)due to its wide optical bandgap and superior stability.In this study,we have modulated the Ni26 vacancies in NiOx film by controlling deposition temperature in a hot-casting process,resulting the change of coordination structure and charge state of NiOx.Moreover,the change of the HOMO level of NiOx makes it more compatible with perovskite to decrease energy losses and enhance hole carrier injection efficiency.Besides,the defect modulation in the electronic structure of NiOx is beneficial for increasing the electrical conductivity and mobility,which are considered to achieve the balance of charge carrier transport and avoid charge accumulation at the interface between perovskite and HTL effectively.Both experimental analyses and theoretical calculations reveal the increase of nickel vacancy defects change the electronic structure of NiOx by increasing the ratio of Ni3^+/Ni2^+-and improving the p-type characteristics.Accordingly,an optimal deposition temperature at 120℃enabled a 36.24%improvement in the power conversion efficiency compared to that deposited at room temperature(25℃).Therefore,this work provides a facile method to manipulate the electronic structure of NiOx to improve the charge carrier transport and photovoltaic performance of related PSCs.展开更多
During the last few years, the preparation of novel fluorescent probes for the detection of carbon dioxide has attracted considerable attention since carbon dioxide plays extremely important roles in widespread fields...During the last few years, the preparation of novel fluorescent probes for the detection of carbon dioxide has attracted considerable attention since carbon dioxide plays extremely important roles in widespread fields including chemical, environmental, clinical analysis, and agri-food industry. This review focuses on the recent advances in the design principles, recognition mechanisms, and preparation of small-molecule fluorescent probes for the selective detection and monitoring of CO;. Moreover, their properties and functions will be discussed detailedly as well.展开更多
The mechanism of Cu enrichment is closely linked to the differentiation of mantle-derived magma and subsequent magmatic-hydrothermal processes.Experimental determination of Cu speciation and partitioning coefficients ...The mechanism of Cu enrichment is closely linked to the differentiation of mantle-derived magma and subsequent magmatic-hydrothermal processes.Experimental determination of Cu speciation and partitioning coefficients among minerals,melts,and fluids(including vapor)is critical for understanding the mobility and enrichment of Cu during magma differentiation,crystallization along cooling,fluid exsolution,the precipitation of Cu-bearing minerals,and water-rock interactions under subsolidus conditions.The summarization of experimental data demonstrates that Cu predominantly exists as cuprous ions(Cu^(+))in both ore fluids and melts at temperatures above 100℃.The speciation of Cu species is affected by the system's components and temperature.In Cl-and S-poor silicate melts,Cu primarily exists as CuO_(0.5).In hydrothermal fluids with intermediate to low salinities at temperatures above 300℃,the dominant species are[CuCl]^(0),[CuCl_(2)]^(-) and CuHS^(0).At lower temperatures(<300℃),in alkaline and intermediate to low salinity fluids,Cu(HS)_(2)^(-) and CuHS0become more prevalent.Cu^(2+) and Cu^(+) readily form higher coordination complexes with Cl in hypersaline brines.Experimental data of Cu partition coefficients yield the following sequence:DCusilicate mineral/melt(0.007±0.002–0.82±0.08)CuFe-Ti oxide/melt(0.19±0.02–1.72±0.68)Cufluid/melt(2–2698)Cubrine/vapor(2–7066)Cusulfide/melt(180–42000).Numerical modeling of Cu distribution during magma differentiation,with a potential link to the formation of porphyry Cu deposits,suggests that(i)low-degree partial melting(10%–25%)of S-bearing and S-absent mantle peridotite leads to Cu enrichment in mantle-derived basaltic arc magmas;(ii)sulfur saturation and fluid exsolution during crustal magmatic and hydrothermal processes can cause significant Cu depletion in the melt,while sulfide dissolution tends to enrich Cu in fluids.The combination of natural samples and experimental results indicates that ore-forming fluids with Cu concentrations exceeding 1000 to>10000 ppm can effectively precipitate Cu-bearing minerals such as chalcopyrite.展开更多
The sequential recommendation is a compelling technology for predicting users’next interaction via their historical behaviors.Prior studies have proposed various methods to optimize the recommendation accuracy on dif...The sequential recommendation is a compelling technology for predicting users’next interaction via their historical behaviors.Prior studies have proposed various methods to optimize the recommendation accuracy on different datasets but have not yet explored the intrinsic predictability of sequential recommendation.To this end,we consider applying the popular predictability theory of human movement behavior to this recommendation context.Still,it would incur serious bias in the next moment measurement of the candidate set size,resulting in inaccurate predictability.Therefore,determining the size of the candidate set is the key to quantifying the predictability of sequential recommendations.Here,different from the traditional approach that utilizes topological constraints,we first propose a method to learn inter-item associations from historical behaviors to restrict the size via logical constraints.Then,we extend it by 10 excellent recommendation algorithms to learn deeper associations between user behavior.Our two methods show significant improvement over existing methods in scenarios that deal with few repeated behaviors and large sets of behaviors.Finally,a prediction rate between 64%and 80%has been obtained by testing on five classical datasets in three domains of the recommender system.This provides a guideline to optimize the recommendation algorithm for a given dataset.展开更多
Let Г=Cay(G,S)be the Cayley graph of a group G with respect to its subset S.The graph is said to be normal edge-transitive if the normalizer of G in the automorphism group Aut(T)of F acts transitively on the edge set...Let Г=Cay(G,S)be the Cayley graph of a group G with respect to its subset S.The graph is said to be normal edge-transitive if the normalizer of G in the automorphism group Aut(T)of F acts transitively on the edge set of ГIn this paper,we study the structure of normal edge-transitive Cayley graphs on a class of non-abelian groups with order 2p^(2)(p refers to an odd prime).The structure and automorphism groups of the non-abelian groups are first presented,and then the tetravalent normal edge-transitive Cayley graphs on such groups are investigated.Finally,the normal edge-transitive Cayley graphs on group G are characterized and classified.展开更多
Reprogrammable soft matter brings flexibility to soft robots so that they can display various motions,which is flourishing in soft robotics.However,the reprogramming of photoresponsive materials used in soft robots is...Reprogrammable soft matter brings flexibility to soft robots so that they can display various motions,which is flourishing in soft robotics.However,the reprogramming of photoresponsive materials used in soft robots is time-consuming using existing methods.In this study,we promote a strategy for rapid reprogramming via switchable photothermal conversion efficiency(PCE).The liquid crystalline elastomers doped with semiconductor bismuth compounds(Bi-LCE)used in this work exhibited large photothermal actuation with over 35%shrinkage in 5 s at high PCE state,which demonstrated little deformation at low PCE state.Furthermore,the material was capable of being reprogrammed up to 10 times,with only 20 min required for one PCE reversible switch.Based on this switchable PCE effect,the same Bi-LCE film displayed various shape changes through different programmable pattern.Additionally,a reprogrammable hollow tube made of PCE reprogrammable materials could tune the diameter,cross-section configuration,and surface morphology,which was crucial for microfluidics field.Reprogrammable materials provide endless possibilities for reusability and sustainability in robotics.展开更多
基金financially supported by the National Natural Science Foundation of China(21706292)support from the Hunan Provincial Science and Technology Plan Project,China(No.2017TP1001).
文摘The practical application of lithium–sulfur(Li–S)batteries is limited by the easy dissolution of polysulfides in the electrolyte,resulting in the lithium polysulfide(LPS)shuttle effect.Several two-dimensional(2D)materials with abundant active binding sites and high surface-to-volume ratios have been developed to prepare functional separators that suppress the diffusion of polysulfides.However,the influence of modified layer thickness on Li+transport has not been considered.Herein,we synthesized individual and multilayered 2D Ti3C2Tx MXene nanosheets and used them to fabricate a series of Ti3C2Tx-PP modified separators.The separators had mass loadings ranging from 0.16 to 0.016 mg cm-2,which is the lowest value reported for 2D materials to the best of our knowledge.The corresponding reductions in thickness ranged from 1.2μm to 100 nm.LPS shuttling was effectively suppressed,even at the lowest mass loading of 0.016 mg cm-2.Suppression was due to the strong interaction between LPS intermediates and Ti atoms and hydroxyl functional groups on the separator surface.The lithium-ion diffusion coefficient increased with the reduction of Ti3C2Tx layers on the separator.Superior cycling stability and rate performance were attained when the separator with a Ti3C2Tx-PP mass loading of 0.016 mg cm-2 was incorporated into a Li–S battery.Carbon nanotubes(CNTs)were introduced into the separators to further improve the electrical and Li+ionic conductivity in the cross-plane direction of the 2D Ti3C2Txlayers.With the ultralightweight Ti3C2Tx/CNTs modified PP separator,the cell maintained a capacity of 640 m Ah g-1after 200cycles at 1C with a capacity decay of only 0.079%per cycle.
文摘In this contribution we use VMS mineral systems in the Bryah rift-basin to constrain the tectonic setting of the widespread mafic and ultramafic magmatism that characterises the rift-basin in question.Two distinct,but temporally closely associated,lithostratigraphic sequences,Narracoota and Karalundi Formations,are discussed.The Karalundi Formation is the main host of VMS mineral systems in the region.The Karalundi Formation consists of turbiditic and immature clastic sediments,which are locally intercalated with basaltic hyaloclastites,dolerites and banded jaspilites.We propose that the basaltic hyaloclastites,dolerites and elastics and jaspilites rocks,form a distinct unit of the Karalundi Formation,named Noonyereena Member.The VMS mineral systems occur near the north-east trendingJenkin Fault and comprise the giant and world-class DeCrussa and the Red Bore deposits.The nature of these deposits and their intimate association with terrigenous clastic rocks and dominantly marine mafic volcanic and subvolcanic rocks,as well as the common development of peperitic margins,are considered indicative of a Besshi-type environment,similar to that of present-day Gulf of California.Our Re-Os age data from a primary pyrite yielded a mean model age of 2012 ± 48 Ma,which coincides（within error） with recent published Re-Os data（Hawke et al.,2015） and confirms the timing of the proposed geodynamic evolution.We propose a geodynamic model that attempts to explain the presence of the Narracoota and Karalundi Formations as the result of mantle plume activity,which began with early uplift of continental crust with intraplate volcanism,followed by early stages of rifting with the deposition of the Karalundi Formation（and Noonyereena Member）,which led to the formation of Besshi-type VMS deposits.With on-going mantle plume activity and early stages of continental separation,an oceanic plateau was formed and is now represented by mafic-ultramafic rocks of the Narracoota Formation.
文摘Objective:To explore the expression of IL-2 and IL-11 and its significance in patients with ankylosing spondylitis(AS).Methods:A total of 48 active AS patients in our hospital and 40 normal control subjects were selected in our study.Bath ankylosing spondylitis disease activity index(BASDAI),Bath ankylosing spondylitis functional index(BASFI),Bath ankylosing spondylitis metrology index(BASMI),ESR and CRP expression levels were compared before treatment,12 h after treatment and 24 h after treatment.IL-2 and IL-11 expression were also compared between these two groups.Results:The BASDAI score,BASH score and BASMI score of the AS patients before treatment significantly decreased compared with those 12 weeks and 24 weeks after treatment(P【0.05).ESB and CRP levels of the AS patients 12 weeks and 24 weeks after treatment significantly decreased compared with those before treatment(P【0.05).Difference was significant in serum IL-2 and IL-11 levels between 12 weeks and 24 weeks after treatment and before treatment(P【0.05).And no statistically significance was observed for serum IL-2 and IL-11 levels between normal control group and those of patients in AS group 24 weeks after treatment(P】0.05). Pearson’s linear-correlation analysis showed that serum IL-2 level had a positive correlation with BASDAI,BASFI,BASMI,ESR and CRP(r=0.661.0.547,0.474,0.362,0.416,P【0.05) and serum IL-11 level had a negative correlation with BASDAI,BASFI,BASMI,ESR and CRP(r=-0.629, -0.412,-0.422,-0.387,-0.408,-0.315,P【0.05).Conclusions:Serum levels of IL-2 in active AS patients significantly increase and will decrease after treatment.However,serum levels of IL- 11 significantly decrease and will increase after treatment,which indicates that serum IL-2 has a positive correlation with the degree of AS and serum IL-11 has a negative correlation with the degree of AS,both of which are correlated closely with the onset of AS.
基金Supported by the Second Tibetan Plateau Scientific Expedition and Research(2021QZKK0303)the Natural Science Basic Research Program of Shaanxi(2020JQ-440 and 2021JQ-327)+1 种基金the Major Science and Technology Project of Xinjiang Uygur Autonomous Region(2021A03001-2)the projects of the China Geological Survey(DD20230333 and DD20230048).
文摘1.Objective In the past decade,a group of medium to giant lead-zinc deposits,represented by Huoshaoyun,Sachakou,and Yuanbaoling,have been discovered in the Aksai Chin region of Karakoram,Xinjiang.They are all located in the Mesozoic carbonate and clastic rock formations.The Sachakou leadzinc mining area is adjacent to the northwest of the Huoshaoyun lead-zinc mining area and is in the same stratigraphic layer as Huoshaoyun.Although many scholars have been arguing about the type and age of Huoshaoyun lead-zinc mineralization,few scholars have paid attention to the classification of the ore-bearing strata in the area.The stratigraphy of the Lower Permian Shenxianwan Group to the Upper Cretaceous Tielongtan Group is exposed in the Sachakou area of Karakorum,Xinjiang,however,the Late Permian-Early Triassic stratigraphy is missing(Fig.1a).Due to the harsh natural conditions in the area and the low level of work,the stratigraphic delineation is not exhaustive,and the regional lithology is dominated by carbonates and clastic rocks,which makes it difficult to identify the age of the regional lithology and causes problems for the exploration and research of lead-zinc in the area.
基金financially supported by the National Natural Science Foundation of China NSFC(51702038)the Recruitment Program for Young Professionals+1 种基金the National Key Research and Development Program of China(2017YFA0206600)the National Natural Science Foundation of China(51773045,21772030,51922032,21961160720)for financial support。
文摘Nickel oxide(NiOx)has exhibited great potential as an inorganic hole transport layer(HTL)in perovskite solar cells(PSCs)due to its wide optical bandgap and superior stability.In this study,we have modulated the Ni26 vacancies in NiOx film by controlling deposition temperature in a hot-casting process,resulting the change of coordination structure and charge state of NiOx.Moreover,the change of the HOMO level of NiOx makes it more compatible with perovskite to decrease energy losses and enhance hole carrier injection efficiency.Besides,the defect modulation in the electronic structure of NiOx is beneficial for increasing the electrical conductivity and mobility,which are considered to achieve the balance of charge carrier transport and avoid charge accumulation at the interface between perovskite and HTL effectively.Both experimental analyses and theoretical calculations reveal the increase of nickel vacancy defects change the electronic structure of NiOx by increasing the ratio of Ni3^+/Ni2^+-and improving the p-type characteristics.Accordingly,an optimal deposition temperature at 120℃enabled a 36.24%improvement in the power conversion efficiency compared to that deposited at room temperature(25℃).Therefore,this work provides a facile method to manipulate the electronic structure of NiOx to improve the charge carrier transport and photovoltaic performance of related PSCs.
基金the National Natural Science Foundation of China (Nos. 21871092, 21672070, 31570360)Shanghai Pujiang Program (No. 18PJD015)+1 种基金STCSM (Nos. 16XD1401000, 17XD14230000)Shanghai Rising-Star Program (No. 16QB1403800) for the financial support
文摘During the last few years, the preparation of novel fluorescent probes for the detection of carbon dioxide has attracted considerable attention since carbon dioxide plays extremely important roles in widespread fields including chemical, environmental, clinical analysis, and agri-food industry. This review focuses on the recent advances in the design principles, recognition mechanisms, and preparation of small-molecule fluorescent probes for the selective detection and monitoring of CO;. Moreover, their properties and functions will be discussed detailedly as well.
基金supported by the Open Project of Key Laboratory,Xinjiang Uygur Autonomous Region,China(Grant No.2023D04067)the National Natural Science Foundation of China(Grant Nos.41972055,42002059,42122014)+1 种基金the National Key Research and Development Program of China(Grant No.2023YFF0804200)the Tianshan Elite Program of Xinjiang Uygur Autonomous Region,China(Grant No.2023TSYCLJ0007)。
文摘The mechanism of Cu enrichment is closely linked to the differentiation of mantle-derived magma and subsequent magmatic-hydrothermal processes.Experimental determination of Cu speciation and partitioning coefficients among minerals,melts,and fluids(including vapor)is critical for understanding the mobility and enrichment of Cu during magma differentiation,crystallization along cooling,fluid exsolution,the precipitation of Cu-bearing minerals,and water-rock interactions under subsolidus conditions.The summarization of experimental data demonstrates that Cu predominantly exists as cuprous ions(Cu^(+))in both ore fluids and melts at temperatures above 100℃.The speciation of Cu species is affected by the system's components and temperature.In Cl-and S-poor silicate melts,Cu primarily exists as CuO_(0.5).In hydrothermal fluids with intermediate to low salinities at temperatures above 300℃,the dominant species are[CuCl]^(0),[CuCl_(2)]^(-) and CuHS^(0).At lower temperatures(<300℃),in alkaline and intermediate to low salinity fluids,Cu(HS)_(2)^(-) and CuHS0become more prevalent.Cu^(2+) and Cu^(+) readily form higher coordination complexes with Cl in hypersaline brines.Experimental data of Cu partition coefficients yield the following sequence:DCusilicate mineral/melt(0.007±0.002–0.82±0.08)CuFe-Ti oxide/melt(0.19±0.02–1.72±0.68)Cufluid/melt(2–2698)Cubrine/vapor(2–7066)Cusulfide/melt(180–42000).Numerical modeling of Cu distribution during magma differentiation,with a potential link to the formation of porphyry Cu deposits,suggests that(i)low-degree partial melting(10%–25%)of S-bearing and S-absent mantle peridotite leads to Cu enrichment in mantle-derived basaltic arc magmas;(ii)sulfur saturation and fluid exsolution during crustal magmatic and hydrothermal processes can cause significant Cu depletion in the melt,while sulfide dissolution tends to enrich Cu in fluids.The combination of natural samples and experimental results indicates that ore-forming fluids with Cu concentrations exceeding 1000 to>10000 ppm can effectively precipitate Cu-bearing minerals such as chalcopyrite.
基金supported in part by the National Natural Science Foundation of China(Grant Nos.61960206008,62002294)the National Science Fund for Distinguished Young Scholars(61725205).
文摘The sequential recommendation is a compelling technology for predicting users’next interaction via their historical behaviors.Prior studies have proposed various methods to optimize the recommendation accuracy on different datasets but have not yet explored the intrinsic predictability of sequential recommendation.To this end,we consider applying the popular predictability theory of human movement behavior to this recommendation context.Still,it would incur serious bias in the next moment measurement of the candidate set size,resulting in inaccurate predictability.Therefore,determining the size of the candidate set is the key to quantifying the predictability of sequential recommendations.Here,different from the traditional approach that utilizes topological constraints,we first propose a method to learn inter-item associations from historical behaviors to restrict the size via logical constraints.Then,we extend it by 10 excellent recommendation algorithms to learn deeper associations between user behavior.Our two methods show significant improvement over existing methods in scenarios that deal with few repeated behaviors and large sets of behaviors.Finally,a prediction rate between 64%and 80%has been obtained by testing on five classical datasets in three domains of the recommender system.This provides a guideline to optimize the recommendation algorithm for a given dataset.
文摘Let Г=Cay(G,S)be the Cayley graph of a group G with respect to its subset S.The graph is said to be normal edge-transitive if the normalizer of G in the automorphism group Aut(T)of F acts transitively on the edge set of ГIn this paper,we study the structure of normal edge-transitive Cayley graphs on a class of non-abelian groups with order 2p^(2)(p refers to an odd prime).The structure and automorphism groups of the non-abelian groups are first presented,and then the tetravalent normal edge-transitive Cayley graphs on such groups are investigated.Finally,the normal edge-transitive Cayley graphs on group G are characterized and classified.
基金supported by the National Natural Science Foundation of China(62075064)the Key R&D Program of Guangzhou(202007020003)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(2021B1515020095,2021A1515110919)the Fundamental Research Funds for the Central Universities(2022ZYGXZR003).
文摘Reprogrammable soft matter brings flexibility to soft robots so that they can display various motions,which is flourishing in soft robotics.However,the reprogramming of photoresponsive materials used in soft robots is time-consuming using existing methods.In this study,we promote a strategy for rapid reprogramming via switchable photothermal conversion efficiency(PCE).The liquid crystalline elastomers doped with semiconductor bismuth compounds(Bi-LCE)used in this work exhibited large photothermal actuation with over 35%shrinkage in 5 s at high PCE state,which demonstrated little deformation at low PCE state.Furthermore,the material was capable of being reprogrammed up to 10 times,with only 20 min required for one PCE reversible switch.Based on this switchable PCE effect,the same Bi-LCE film displayed various shape changes through different programmable pattern.Additionally,a reprogrammable hollow tube made of PCE reprogrammable materials could tune the diameter,cross-section configuration,and surface morphology,which was crucial for microfluidics field.Reprogrammable materials provide endless possibilities for reusability and sustainability in robotics.
