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Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems
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作者 G.Wilson FERNANDES Letícia RAMOS +3 位作者 Dario C.PAIVA Jéssica CUNHA-BLUM Vanessa Matos GOMES Daniel NEGREIROS 《Journal of Mountain Science》 SCIE CSCD 2024年第3期719-733,共15页
Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferrugin... Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low resilience.The determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological restoration.We proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic composition.We described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and soils.All three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia subalata.The distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt concentration.We provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local conditions.Failure to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem services.This study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem. 展开更多
关键词 Canga Ecological restoration Extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships
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What diameter?What height?Influence of measures of average tree size on area-based allometric volume relationships
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作者 Yilin Wang John A.Kershaw +2 位作者 Mark J.Ducey Yuan Sun James B.McCarter 《Forest Ecosystems》 SCIE CSCD 2024年第1期100-109,共10页
Volume is an important attribute used in many forest management decisions.Data from 83 fixed-area plots located in central New Brunswick,Canada,are used to examine how different measures of stand-level diameter and he... Volume is an important attribute used in many forest management decisions.Data from 83 fixed-area plots located in central New Brunswick,Canada,are used to examine how different measures of stand-level diameter and height influence volume prediction using a stand-level variant of Honer's(1967)volume equation.When density was included in the models(Volume=f(Diameter,Height,Density))choice of diameter measure was more important than choice of height measure.When density was not included(Volume=f(Diameter,Height)),the opposite was true.For models with density included,moment-based estimators of stand diameter and height performed better than all other measures.For models without density,largest tree estimators of stand diameter and height performed better than other measures.The overall best equation used quadratic mean diameter,Lorey's height,and density(root mean square error=5.26 m^3·ha^(-1);1.9%relative error).The best equation without density used mean diameter of the largest trees needed to calculate a stand density index of 400 and the mean height of the tallest 400 trees per ha(root mean square error=32.08 m^(3)·ha^(-1);11.8%relative error).The results of this study have some important implications for height subsampling and LiDAR-derived forest inventory analyses. 展开更多
关键词 Allometric relationships Stand structure Volume estimation Stand-level attributes
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Different mechanisms underlie similar species-area relationships in two tropical archipelagoes
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作者 Shengchun Li Tieyao Tu +5 位作者 Shaopeng Li Xian Yang Yong Zheng Liang-Dong Guo Dianxiang Zhang Lin Jiang 《Plant Diversity》 SCIE CAS CSCD 2024年第2期238-246,共9页
Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain elusive.Here,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelag... Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain elusive.Here,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelagoes in the South China Sea.We found positive plant species-area relationships for both coral and continental archipelagoes.However,our results showed that different mechanisms contributed to similar plant species-area relationships between the two archipelagoes.For coral islands,soil nutrients and spatial distance among communities played major roles in shaping plant community structure and species diversity.By contrast,the direct effect of island area,and to a lesser extent,soil nutrients determined plant species richness on continental islands.Intriguingly,increasing soil nutrients availability(N,P,K)had opposite effects on plant diversity between the two archipelagoes.In summary,the habitat quality effect and dispersal limitation are important for regulating plant diversity on coral islands,whereas the passive sampling effect,and to a lesser extent,the habitat quality effect are important for regulating plant diversity on continental islands.More generally,our findings indicate that island plant species-area relationships are outcomes of the interplay of both niche and neutral processes,but the driving mechanisms behind these relationships depends on the type of islands. 展开更多
关键词 Coral and continental islands Plant diversity Soil nutrients Species-area relationships The sampling effect
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A Large-Scale Group Decision Making Model Based on Trust Relationship and Social Network Updating
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作者 Rongrong Ren Luyang Su +2 位作者 Xinyu Meng Jianfang Wang Meng Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期429-458,共30页
With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that consid... With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that considers the trust relationship among decisionmakers(DMs).In the process of consensusmeasurement:the social network is constructed according to the social relationship among DMs,and the Louvain method is introduced to classify social networks to form subgroups.In this study,the weights of each decision maker and each subgroup are computed by comprehensive network weights and trust weights.In the process of consensus improvement:A feedback mechanism with four identification and two direction rules is designed to guide the consensus of the improvement process.Based on the trust relationship among DMs,the preferences are modified,and the corresponding social network is updated to accelerate the consensus.Compared with the previous research,the proposedmodel not only allows the subgroups to be reconstructed and updated during the adjustment process,but also improves the accuracy of the adjustment by the feedbackmechanism.Finally,an example analysis is conducted to verify the effectiveness and flexibility of the proposed method.Moreover,compared with previous studies,the superiority of the proposed method in solving the LGDM problem is highlighted. 展开更多
关键词 Large-scale group decision making social network updating trust relationship group consensus feedback mechanism
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The Relationship between Father-Love Absence and Loneliness:Based on the Perspective of the Social Functionalist Theory and the Social Needs Theory
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作者 Yaping Zhou He Zhong +1 位作者 Xiaojun Li Yanhui Xiang 《International Journal of Mental Health Promotion》 2024年第2期139-148,共10页
Fathers play an important role in adolescents’development,which is significant for their development and influences their mental health,including feeling of loneliness.However,the effects and mechanisms of father-lov... Fathers play an important role in adolescents’development,which is significant for their development and influences their mental health,including feeling of loneliness.However,the effects and mechanisms of father-love absence on individual loneliness are not clear.Based on the social functionalist theory and the social needs theory,this study examines the influence of individual fatherlove absence on loneliness and its underlying mechanisms.A questionnaire survey was administered to 319 junior high school students and 1,476 high school students.The results showed that adolescents with father-love absence had higher levels of loneliness,and that father-love absence affected loneliness levels through mediating pathways of individual gratitude,peer relationships,and gratitude to peer relationships.This study not only confirms the negative effects of father-love absence on adolescents’loneliness,but also explains the mediate roles of individual gratitude and peer relationships.It enriches the theoretical system related to family education and has important theoretical and practical implications for further interventions on adolescents’mental health from the perspective of fatherless parenting. 展开更多
关键词 Father-love absence LONELINESS GRATITUDE peer relationships
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Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Average Path Length of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Zhang Xiaoxuan Li Yangqi 《Journal of Traffic and Transportation Engineering》 2024年第1期11-22,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001... In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the node average path length of China aviation network in 1988,1994,2001,2008 and 2015 was calculated.Through regression analysis,it was found that the node degree had a logarithmic relationship with the average length of node path,and the two parameters of the logarithmic relationship had linear evolutionary trace.Key word:China aviation network,complex network,node degree,average length of node path,logarithmic relationship,evolutionary trace. 展开更多
关键词 China aviation network complex network node degree average length of node path logarithmic relationship evolutionary trace.
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Review on mechanisms and structure-activity relationship of hypoglycemic effects of polysaccharides from natural resources 被引量:2
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作者 Xiaolong Ji Jianhang Guo +3 位作者 Tengzheng Cao Tingting Zhang Yanqi Liu Yizhe Yan 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期1969-1980,共12页
Diabetes mellitus(DM)is a common multifactorial disease,causing various complications,such as chronic metabolism.The current therapies for diabetes mellitus are commercial diabetic drugs that have different definite s... Diabetes mellitus(DM)is a common multifactorial disease,causing various complications,such as chronic metabolism.The current therapies for diabetes mellitus are commercial diabetic drugs that have different definite side effect.However,polysaccharides mainly extracted from natural resources,have advantages of safety,accessibility,and anti-diabetic potential.We have summarized recent research of natural polysaccharides with hypoglycemic activities,focusing on different pharmacological mechanisms in various cell and animal models.The relationships of structure-hypoglycemic effect are also discussed in detail.This review could provide a comprehensive perspective for better understanding on development and mechanism of natural polysaccharides against diabetes mellitus,which have been required by clinical studies yet. 展开更多
关键词 POLYSACCHARIDES Hypoglycemic effect MECHANISMS Structure-activity relationship
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Mediating role of physical activity in the relationship between psychological distress and intimate relationships among stroke patients 被引量:1
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作者 Chang-Yue Luo Peng Jiao +2 位作者 Shu-Min Tu Lin Shen Yong-Mei Sun 《World Journal of Psychiatry》 SCIE 2023年第12期1096-1105,共10页
BACKGROUND Stroke patients often experience psychological distress,which can impact their intimate relationships with spouses,subsequently influencing their treatment and recovery.Physical activity is considered a key... BACKGROUND Stroke patients often experience psychological distress,which can impact their intimate relationships with spouses,subsequently influencing their treatment and recovery.Physical activity is considered a key rehabilitation method for stroke patients.This paper aims to analyze whether psychological distress affects intimate relationship between spouses through physical activity.AIM To explore the mediating effect of physical activity between psychological distress and intimate relationship in stroke patients.METHODS A total of 256 stroke patients who underwent treatment at the First People’s Hospital of Shangqiu between July 2021 and July 2022 were enrolled in this study.The participants completed questionnaires,including the Kessler Psychological Distress Scale(K10),the Quality of Relationship Index(QRI),International Physical Activity Questionnaire,and a general information questionnaire.Data analysis were performed using SPSS 23.0.The Harman test was employed to detect common method deviations,and Spearman correlation was used for correlation analysis.The mediating effect was assessed using Process 3.4.1,with significance testing of the regression coefficients conducted using the bias-corrected percentile Bootstrap method(5000 iterations,95%confidence interval).Statistical significance was set at P<0.05.RESULTS The results showed that patients scored an average of 21.61±6.44 points on the K10,32.40±6.19 points on the QRI;the median physical activity level according to the International Physical Activity Questionnaire was 1861(566,2846)MET·min/w.The level of physical activity(the physical activity intensity of the patients reflected by the Interna-tional Physical Activity Questionnaire-Long Form scale)negatively correlated with psychological distress and intimacy(P<0.05),and positively correlated with each other(P<0.05),with the correlation stronger at lower physical activity levels compared to higher ones.The mediating effect of physical activity between psychological distress and intimate relationship was calculated to be 40.23%.Bootstrap analysis further validated the results.The mediating effect of psychological distress on intimate relationships through physical activity level was-0.284,with a confidence interval of-0.409 to-0.163,excluding 0,confirming a significant mediating effect of psychological distress on intimate relationships.CONCLUSION Physical activity significantly affects relationship between psychological distress and intimate relationships among stroke patients.Addressing the role of physical activity may have implications for improving patient outcomes and rehabilitation strategies. 展开更多
关键词 STROKE Cross-sectional study Psychological distress Intimate relationship Mediating effect Physical activity level
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Experimental investigation on the enhanced oil recovery efficiency of polymeric surfactant: Matching relationship with core and emulsification ability
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作者 Xin Chen Yi-Qiang Li +3 位作者 Zhe-Yu Liu Japan Trivedi Wen-Bin Gao Ming-Yue Sui 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期619-635,共17页
The polymeric surfactant can be used as an efficient agent for enhanced oil recovery(EOR)because of its large bulk viscosity and good interfacial activity.However,there is a sparse understanding of its matching relati... The polymeric surfactant can be used as an efficient agent for enhanced oil recovery(EOR)because of its large bulk viscosity and good interfacial activity.However,there is a sparse understanding of its matching relationship with reservoirs and emulsification occurrence conditions,which may affect its migration and EOR efficiency.One intermolecular association molecule polymeric surfactant(IAM)was synthesized by micellar polymerization and characterized with 1 H NMR,FTIR,and TGA.The matching relationship between IAM and reservoirs was evaluated by comparing the viscosity retention rate of effluent in the core flow experiments.Moreover,the effect of the matching relationship on EOR in the heterogeneous reservoir was clarified with parallel core displacement experiments by considering different flow abilities of IAM in the high-permeability layer.The occurrence conditions of in-situ emulsification of IAM were evaluated via oil-water co-injection experiments under the different injection rates and oil-water ratios.Microscopic visualization displacement was carried out to compare the micro EOR mechanisms of different chemical systems.The results show that IAM features thickening,shearing resistance,viscoelasticity,thermal stability,and interfacial activity.The matching relationship between cores and IAM could be divided as hardly injected,flow limited,and flow smoothly,corresponding to the viscosity retention ratio of<20%,20%-80%,and>80%,respectively.IAM could gain better EOR efficiency(17.69%)when its matching relationship to the high permeability layer was“flow limited”.The defined mixture capillary number shows that only when it is greater than 1×10^(3),the in-situ emulsions can be generated.Compared to HPAM,IAM could reduce IFT and form vortices to more effectively displace film and corner remaining oils by stripping and peeling off crude oil.The formed emulsion accumulated at the pore throat could further increase flow resistance,which benefits swept area enlargement.This work could provide theoretical and data support for the parameters design in the polymeric surfactant practical application. 展开更多
关键词 Migration Matching relationship Viscosity retention ratio EMULSION EOR
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Feasibility of the 2-point method to determine the load-velocity relationship variables during the countermovement jump exercise
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作者 Alejandro Pérez-Castilla Rodrigo Ramirez-Campillo +1 位作者 John F.T.Fernandes Amador García-Ramos 《Journal of Sport and Health Science》 SCIE CAS CSCD 2023年第4期544-552,F0003,共10页
Purpose:This study aimed to examine the reliability and validity of load-velocity(L-V)relationship variables obtained through the 2-point method using different load combinations and velocity variables.Methods:Twenty ... Purpose:This study aimed to examine the reliability and validity of load-velocity(L-V)relationship variables obtained through the 2-point method using different load combinations and velocity variables.Methods:Twenty men performed 2 identical sessions consisting of 2 countermovement jumps against 4 external loads(20 kg,40 kg,60 kg,and80 kg)and a heavy squat against a load linked to a mean velocity(MV)of 0.55 m/s(load_(0.55)).The L-V relationship variables(load-axis intercept(L_(0)),velocity-axis intercept(v_(0)),and area under the L-V relationship line(A_(line)))were obtained using 3 velocity variables(MV,mean propulsive velocity(MPV),and peak velocity)by the multiple-point method including(20-40-60-80-load_(0.55))and excluding(20-40-60-80)the heavy squat,as well as from their respective 2-point methods(20-load_(0.55)and 20-80).Results:The L-V relationship variables were obtained with an acceptable reliability(coefncient of variation(CV)≤7.30%;intra-class correlation coefficient>0.63).The reliability of L_(0)and v_(0)was comparable for both methods(CV_(ratio)(calculated as higher value/lower value):1.11-1.12),but the multiple-point method provided Al_(ine)with a greater reliability(CV_(ratio)=1.26).The use of a heavy squat provided the L-V relationship variables with a comparable or higher reliability than the use of a heavy countermovement jump load(CV_(ratio):1.06-1.19).The peak velocity provided the load-velocity relationship variables with the greatest reliability(CV_(ratio):1.15-1.86)followed by the MV(CV_(ratio):1.07-1.18),and finally the MPV.The 2-point methods only revealed an acceptable validity for the MV and MPV(effect size≤0.19;Pearson s product-moment correlation coefficient≥0.96;Lin's concordance correlation coefficient≥0.94).Conclusion:The 2-point method obtained from a heavy squat load and MV or MPV is a quick,safe,and reliable procedure to evaluate the lower-body maximal neuromuscular capacities through the L-V relationship. 展开更多
关键词 Force-velocity relationship Mean velocity Multiple-point method Peak velocity Velocity-based training
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The worldwide allometric relationship in anatomical structures for plant roots
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作者 Yue Zhang Jing-Jing Cao +3 位作者 Qing-Pei Yang Ming-Zuo Wu Yong Zhao De-Liang Kong 《Plant Diversity》 SCIE CAS CSCD 2023年第6期621-629,共9页
The cortex(i.e.,absorptive tissue)and stele(transportive vascular tissue)are fundamental to the function of plant roots.Unraveling how these anatomical structures are assembled in absorptive roots is essential for our... The cortex(i.e.,absorptive tissue)and stele(transportive vascular tissue)are fundamental to the function of plant roots.Unraveling how these anatomical structures are assembled in absorptive roots is essential for our understanding of plant ecology,physiology,and plant responses to global environmental changes.In this review,we first compile a large data set on anatomical traits in absorptive roots,including cortex thickness and stele radius,across 698 observations and 512 species.Using this data set,we reveal a common root allometry in absorptive root structures,i.e.,cortex thickness increases much faster than stele radius with increasing root diameter(hereafter,root allometry).Root allometry is further validated within and across plant growth forms(woody,grass,and liana species),mycorrhiza types(arbuscular mycorrhiza,ectomycorrhiza,and orchid mycorrhizas),phylogenetic gradients(from ferns to Orchidaceae),and environmental change scenarios(e.g.,elevation of atmospheric CO_(2)concentration and nitrogen fertilization).These findings indicate that root allometry is common in plants.Importantly,root allometry varies greatly across species.We then summarize recent research on the mechanisms of root allometry and potential issues regarding these mechanisms.We further discuss ecological and evolutionary implications of root allometry.Finally,we propose several important research directions that should be pursued regarding root allometry. 展开更多
关键词 Allometric relationship Root dimeter Cortex thickness Stele radius
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Tuning Active Metal Atomic Spacing by Filling of Light Atoms and Resulting Reversed Hydrogen Adsorption-Distance Relationship for Efficient Catalysis
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作者 Ding Chen Ruihu Lu +11 位作者 Ruohan Yu Hongyu Zhao Dulan Wu Youtao Yao Kesong Yu Jiawei Zhu Pengxia Ji Zonghua Pu Zongkui Kou Jun Yu Jinsong Wu Shichun Mu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期151-162,共12页
Precisely tuning the spacing of the active centers on the atomic scale is of great significance to improve the catalytic activity and deepen the understanding of the catalytic mechanism,but still remains a challenge.H... Precisely tuning the spacing of the active centers on the atomic scale is of great significance to improve the catalytic activity and deepen the understanding of the catalytic mechanism,but still remains a challenge.Here,we develop a strategy to dilute catalytically active metal interatomic spacing(d_(M-M))with light atoms and discover the unusual adsorption patterns.For example,by elevating the content of boron as interstitial atoms,the atomic spacing of osmium(d_(Os-Os))gradually increases from 2.73 to 2.96?.More importantly,we find that,with the increase in dOs-Os,the hydrogen adsorption-distance relationship is reversed via downshifting d-band states,which breaks the traditional cognition,thereby optimizing the H adsorption and H_2O dissociation on the electrode surface during the catalytic process;this finally leads to a nearly linear increase in hydrogen evolution reaction activity.Namely,the maximum dOs-Os of 2.96?presents the optimal HER activity(8 mV@10 mA cm^(-2))in alkaline media as well as suppressed O adsorption and thus promoted stability.It is believed that this novel atomic-level distance modulation strategy of catalytic sites and the reversed hydrogen adsorption-distance relationship can shew new insights for optimal design of highly efficient catalysts. 展开更多
关键词 ELECTROCATALYSIS DFT calculation Interstitial filling Hydrogen evolution Structure–activity relationships
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Four new orientation relationships of Mg_(17)Al_(12) phase with magnesium matrix in Mg-8Al-0.5Zn alloys
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作者 Feiya Liu Renlong Xin +2 位作者 Xin Wen Xinfu Gu Qing Liu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第12期4689-4695,共7页
Although the non-basal precipitates, those not parallel to the basal plane, are more effective to block basal slip in Mg-Al alloys, the crystallographic orientation relationship(OR) between these precipitates and the ... Although the non-basal precipitates, those not parallel to the basal plane, are more effective to block basal slip in Mg-Al alloys, the crystallographic orientation relationship(OR) between these precipitates and the α-Mg matrix has not been well established. In this work, the crystallography of the non-basal Mg_(17)Al_(12) precipitates in AZ80 alloy was systematically investigated by transmission electron microscopy(TEM). By tilting to a suitable electron beam direction, different kinds of non-basal precipitates were recognized in TEM, and the following four new ORs between the non-basal Mg_(17)Al_(12) precipitates and the matrix were revealed: ■, and ■.Furthermore, these ORs and their habit planes were explained using the edge-to-edge matching model. The findings in this work can provide some guidelines for designing the microstructure of Mg-Al alloys to enhance their precipitation hardening potential. 展开更多
关键词 Mg alloys PRECIPITATE Orientation relationship CRYSTALLOGRAPHY Edge-to-edge matching model
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Solubility study of hydrogen in direct coal liquefaction solvent based on quantitative structure–property relationships model
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作者 Xiao-Bin Zhang A.Rajendran +1 位作者 Xing-Bao Wang Wen-Ying Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期250-258,共9页
Direct coal liquefaction(DCL)is an important and effective method of converting coal into high-valueadded chemicals and fuel oil.In DCL,heating the direct coal liquefaction solvent(DCLS)from low to high temperature an... Direct coal liquefaction(DCL)is an important and effective method of converting coal into high-valueadded chemicals and fuel oil.In DCL,heating the direct coal liquefaction solvent(DCLS)from low to high temperature and pre-hydrogenation of the DCLS are critical steps.Therefore,studying the dissolution of hydrogen in DCLS under liquefaction conditions gains importance.However,it is difficult to precisely determine hydrogen solubility only by experiments,especially under the actual DCL conditions.To address this issue,we developed a prediction model of hydrogen solubility in a single solvent based on the machine-learning quantitative structure–property relationship(ML-QSPR)methods.The results showed that the squared correlation coefficient R^(2)=0.92 and root mean square error RMSE=0.095,indicating the model’s good statistical performance.The external validation of the model also reveals excellent accuracy and predictive ability.Molecular polarization(a)is the main factor affecting the dissolution of hydrogen in DCLS.The hydrogen solubility in acyclic alkanes increases with increasing carbon number.Whereas in polycyclic aromatics,it decreases with increasing ring number,and in hydrogenated aromatics,it increases with hydrogenation degree.This work provides a new reference for the selection and proportioning of DCLS,i.e.,a solvent with higher hydrogen solubility can be added to provide active hydrogen for the reaction and thus reduce the hydrogen pressure.Besides,it brings important insight into the theoretical significance and practical value of the DCL. 展开更多
关键词 Hydrogen solubility Liquefied solvents Predictive model Density generalized function theory Quantitative structure-property relationship
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Mass transfer mechanism and relationship of gas–liquid annular flow in a microfluidic cross-junction device
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作者 Xin Xu Na Xu +3 位作者 Wei Zhang Junwen Wang Yao Li Chen Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期37-48,共12页
Mass transfer performance of gas–liquid two-phase flow at microscale is the basis of application of microreactor in gas–liquid reaction systems.At present,few researches on the mass transfer property of annular flow... Mass transfer performance of gas–liquid two-phase flow at microscale is the basis of application of microreactor in gas–liquid reaction systems.At present,few researches on the mass transfer property of annular flow have been reported.Therefore,the mass transfer mechanism and relationship of gas–liquid annular flow in a microfluidic cross-junction device are studied in the present study.We find that the main factors,i.e.,flow pattern,liquid film thickness,liquid hydraulic retention time,phase interface fluctuation,and gas flow vorticity,which influence the flow mass transfer property,are directly affected both by gas and liquid flow velocities.But the influences of gas and liquid velocities on different mass transfer influencing factors are different.Thereout,the fitting relationships between gas and liquid flow velocities and mass transfer influencing factors are established.By comparing the results from calculations using fitting equations and simulations,it shows that the fitting equations have relatively high degrees of accuracy.Finally,the Pareto front,namely the Pareto optimal solution set,of gas and liquid velocity conditions for the best flow mass transfer property is obtained using the method of multi-objective particle swarm optimization.It is proved that the mass transfer property of the gas–liquid two-phase flow can be obviously enhanced under the guidance of the obtained Pareto optimal solution set through experimental verification. 展开更多
关键词 Gas-liquid microreactor Annular flow Mass transfer mechanism Mass transfer relationship Multi-objective particle swarm optimization
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A novel binary effective medium model to describe the prepeak stressstrain relationship of combined bodies of rock-like material and rock
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作者 Tienan Wang Yue Zhai +2 位作者 Huan Gao Yubai Li Ruifeng Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第5期601-616,共16页
Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body ... Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body lack a binary feature.Based on effective medium theory,this paper presents the governing equation of the“elastic modulus”for combined and single bodies under triaxial compressive tests.A binary effective medium model is then established.Based on the compressive experiment of concretegranite combined bodies,the feasibility of determining the stress threshold based on crack axial strain is discussed,and the model is verified.The model is further extended to coal-rock combined bodies of more diverse types,and the variation laws of the compressive mechanical parameters are then discussed.The results show that the fitting accuracy of the model with the experimental curves of the concretegranite combined bodies and various types of coal-rock combined bodies are over 95%.The crack axial strain method can replace the crack volumetric strain method,which clarifies the physical meanings of the model parameters.The variation laws of matrix parameters and crack parameters are discussed in depth and are expected to be more widely used in geotechnical engineering. 展开更多
关键词 Combined body stress-strain relationship Hooke’s law Effective medium theory Stress threshold determination
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Structure-guided Capacitance Relationships in Oxidized Graphene Porous Materials Based Supercapacitors
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作者 Srinivas Gadipelli Hanieh Akbari +4 位作者 Juntao Li Christopher A.Howard Hong Zhang Paul R.Shearing Dan J.L.Brett 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期58-69,共12页
Supercapacitors formed from porous carbon and graphene-oxide(GO)materials are usually dominated by either electric double-layer capacitance,pseudo-capacitance,or both.Due to these combined features,reduced GO material... Supercapacitors formed from porous carbon and graphene-oxide(GO)materials are usually dominated by either electric double-layer capacitance,pseudo-capacitance,or both.Due to these combined features,reduced GO materials have been shown to offer superior capacitance over typical nanoporous carbon materials;however,there is a significant variation in reported values,ranging between 25 and 350 F g^(−1).This undermines the structure(e.g.,oxygen functionality and/or surface area)-performance relationships for optimization of cost and scalable factors.This work demonstrates important structure-controlled charge storage relationships.For this,a series of exfoliated graphene(EG)derivatives are produced via thermal-shock exfoliation of GO precursors and following controlled graphitization of EG(GEG)generates materials with varied amounts of porosity,redox-active oxygen groups and graphitic components.Experimental results show significantly varied capacitance values between 30 and 250 F g^(−1)at 1.0 A g^(−1)in GEG structures;this suggests that for a given specific surface area the redox-active and hydrophilic oxygen content can boost the capacitance to 250–300%higher compared to typical mesoporous carbon materials.GEGs with identical oxygen functionality show a surface area governed capacitance.This allows to establish direct structure-performance relationships between 1)redox-active oxygen functional concentration and capacitance and 2)surface area and capacitance. 展开更多
关键词 electric double-layer capacitance graphene-oxide PSEUDOCAPACITANCE structure-performance relationships SUPERCAPACITORS
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Screening hepatoprotective effective components of Lonicerae japonica Flos based on the spectrum-effect relationship and its mechanism exploring
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作者 Song Wang Lin Yang +4 位作者 Ajiao Hou Songtao Liu Liu Yang Haixue Kuang Hai Jiang 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期283-294,共12页
Lonicerae japonicae Flos(LF)is a kind of healthcare food with hepatoprotective function.This study was designed to explore the spectrum-effect relationships between UPLC fingerprints and the hepatoprotective effects o... Lonicerae japonicae Flos(LF)is a kind of healthcare food with hepatoprotective function.This study was designed to explore the spectrum-effect relationships between UPLC fingerprints and the hepatoprotective effects of LF.Fingerprints of ten batches of LF were established by UPLC-PDA.The inhibitory levels of AST and ALT were used as pharmacological indexes,and secoxyloganin,isochlorogenic acid A and isochlorogenic acid C were screened as hepatoprotective active compounds by grey relational analysis(GRA)and partial least squares regression analysis(PLSR).Caspase-3 was obtained by network pharmacology as a key target of hepatoprotective active compounds.Molecular docking is used to explore the interaction between small molecules and proteins.This work provided a general model of the combination of UPLC-PDA and hepatoprotective effect to study the spectrum-effect relationship of LF,which can be used to considerable methods and insight for the fundamental research of the material basis of similar healthcare food. 展开更多
关键词 Lonicerae japonicae Flos Hepatoprotective effect Spectrum-effect relationship Molecular docking MECHANISM
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The Entity Relationship Extraction Method Using Improved RoBERTa and Multi-Task Learning
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作者 Chaoyu Fan 《Computers, Materials & Continua》 SCIE EI 2023年第11期1719-1738,共20页
There is a growing amount of data uploaded to the internet every day and it is important to understand the volume of those data to find a better scheme to process them.However,the volume of internet data is beyond the... There is a growing amount of data uploaded to the internet every day and it is important to understand the volume of those data to find a better scheme to process them.However,the volume of internet data is beyond the processing capabilities of the current internet infrastructure.Therefore,engineering works using technology to organize and analyze information and extract useful information are interesting in both industry and academia.The goal of this paper is to explore the entity relationship based on deep learning,introduce semantic knowledge by using the prepared language model,develop an advanced entity relationship information extraction method by combining Robustly Optimized BERT Approach(RoBERTa)and multi-task learning,and combine the intelligent characters in the field of linguistic,called Robustly Optimized BERT Approach+Multi-Task Learning(RoBERTa+MTL).To improve the effectiveness of model interaction,multi-task teaching is used to implement the observation information of auxiliary tasks.Experimental results show that our method has achieved an accuracy of 88.95 entity relationship extraction,and a further it has achieved 86.35%of accuracy after being combined with multi-task learning. 展开更多
关键词 Entity relationship extraction Multi-Task Learning RoBERTa
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Consensus model of social network group decision-making based on trust relationship among experts and expert reliability
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作者 WANG Ya CAI Mei JIAN Xinglian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1576-1588,共13页
Due to people’s increasing dependence on social networks,it is essential to develop a consensus model considering not only their own factors but also the interaction between people.Both external trust relationship am... Due to people’s increasing dependence on social networks,it is essential to develop a consensus model considering not only their own factors but also the interaction between people.Both external trust relationship among experts and the internal reliability of experts are important factors in decision-making.This paper focuses on improving the scientificity and effectiveness of decision-making and presents a consensus model combining trust relationship among experts and expert reliability in social network group decision-making(SN-GDM).A concept named matching degree is proposed to measure expert reliability.Meanwhile,linguistic information is applied to manage the imprecise and vague information.Matching degree is expressed by a 2-tuple linguistic model,and experts’preferences are measured by a probabilistic linguistic term set(PLTS).Subsequently,a hybrid weight is explored to weigh experts’importance in a group.Then a consensus measure is introduced and a feedback mechanism is developed to produce some personalized recommendations with higher group consensus.Finally,a comparative example is provided to prove the scientificity and effectiveness of the proposed consensus model. 展开更多
关键词 social network group decision-making(SN-GDM) trust relationship expert reliability consensus model probabilistic linguistic term set(PLTS).
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