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Deepening the Curriculum Reform to Cultivate Student's Practical and Creative Ability: A Case Study of School of Arts & Design of Nanjing Vocational Institute of Industry Technology
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作者 LU Lei 《Journal of Landscape Research》 2016年第5期85-86,89,共3页
With the advance of curriculum reform, innovative education has become the calling of Chinese vocational education. Based on the case study of Nanjing Vocational Institute of Industry Technology, the paper is to explo... With the advance of curriculum reform, innovative education has become the calling of Chinese vocational education. Based on the case study of Nanjing Vocational Institute of Industry Technology, the paper is to explore methods and approaches of deepening the curriculum reform to cultivate student's practical and creative ability from following aspects: creating an open teaching environment to cultivate students' innovative consciousness, setting open teaching contents to foster students' creative thinking, and establishing an open assessment system to test students' innovation ability. 展开更多
关键词 Curriculum reform Practice and innovation Ability cultivating
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Research on the Campus Cultural Landscape of the Tibetan-Yi Corridor:Taking the Middle and Primary Schools in Meigu County of Liangshan Yi Autonomous Prefecture as an Example
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作者 Xueli Wang Hangchuan Dong +1 位作者 Xi Pan Siwei Yu 《Journal of Architectural Research and Development》 2024年第3期98-103,共6页
In view of rural revitalization,the Meigu area,as a key region of the Tibetan-Yi Corridor,faces challenges in educational development and the construction of campus cultural landscapes.Campus landscape culture,as the ... In view of rural revitalization,the Meigu area,as a key region of the Tibetan-Yi Corridor,faces challenges in educational development and the construction of campus cultural landscapes.Campus landscape culture,as the foundation of campus culture,is one of the important factors affecting the quality of campus education.Integrating traditional cultural elements such as Yi patterns and totems into the design can effectively enhance the aesthetic of the campus,promote the local ethnic characteristic culture,and inject new vitality into rural revitalization.Therefore,this paper applies traditional Yi cultural elements to the design of campus cultural landscapes.This is of great significance for improving the rural school environment and enhancing students’enthusiasm for learning and cultural identity.Besides,it provides an alternative for the preservation and development of local culture. 展开更多
关键词 Campus landscape design Tibetan-Yi culture Rural revitalization
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Novel Investigation of Stochastic Fractional Differential Equations Measles Model via the White Noise and Global Derivative Operator Depending on Mittag-Leffler Kernel 被引量:1
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作者 Saima Rashid Fahd Jarad 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2289-2327,共39页
Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this p... Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this paper,we constructed a stochastic fractional framework of measles spreading mechanisms with dual medication immunization considering the exponential decay and Mittag-Leffler kernels.In this approach,the overall population was separated into five cohorts.Furthermore,the descriptive behavior of the system was investigated,including prerequisites for the positivity of solutions,invariant domain of the solution,presence and stability of equilibrium points,and sensitivity analysis.We included a stochastic element in every cohort and employed linear growth and Lipschitz criteria to show the existence and uniqueness of solutions.Several numerical simulations for various fractional orders and randomization intensities are illustrated. 展开更多
关键词 Measles epidemic model Atangana-Baleanu Caputo-Fabrizio differential operators existence and uniqueness qualitative analysis Newton interpolating polynomial
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Understanding the oxidation chemistry of Ti_(3)C_(2)T_(x)(MXene)sheets and their catalytic performances 被引量:1
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作者 Suvdanchimeg Sunderiya Selengesuren Suragtkhuu +9 位作者 Solongo Purevdorj Tumentsereg Ochirkhuyag Munkhjargal Bat-Erdene Purevlkham Myagmarsereejid Ashley DSlattery Abdulaziz SRBati Joseph GShapter Dorj Odkhuu Sarangerel Davaasambuu Munkhbayar Batmunkh 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期437-445,I0010,共10页
Transition metal carbides and nitrides(MXenes)nanosheets are attractive two-dimensional(2D)materials,but they suffer from oxidation/degradation issues during storage and/or applications due to their sensitivity to wat... Transition metal carbides and nitrides(MXenes)nanosheets are attractive two-dimensional(2D)materials,but they suffer from oxidation/degradation issues during storage and/or applications due to their sensitivity to water and oxygen.Despite the great research progress,the exact oxidation kinetics of Ti_(3)C_(2)T_(x)(MXene)and their final products after oxidation are not fully understood.Herein,we systematically tracked the oxidation process of few-layer Ti_(3)C_(2)T_(x) nanosheets in an aqueous solution at room temperature over several weeks.We also studied the oxidation effects on the electrocatalytic properties of Ti_(3)C_(2)T_(x) for hydrogen evolution reaction and found that the overpotential to achieve a current density of 10 mA cm^(-2)increases from 0.435 to 0.877 V after three weeks of degradation,followed by improvement to stabilized values of around 0.40 V after eight weeks.These results suggest that severely oxidized MXene could be a promising candidate for designing efficient catalysts.According to our detailed experimental characterization and theoretical calculations,unlike previous studies,black titanium oxide is formed as the final product in addition to white Ti(IV)oxide and disordered carbons after the complete oxidation of Ti_(3)C_(2)T_(x).This work presents significant advancements in better understanding of 2D Ti_(3)C_(2)T_(x)(MXene)oxidation and enhances the prospects of this material for various applications. 展开更多
关键词 2D materials MXene Chemical degradation CATALYSIS Hydrogen evolution reaction
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Characterizations of semihoops based on derivations
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作者 WANG Mei ZHANG Xiao-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期291-310,共20页
In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of them.Then,we prove that every Heyting algebra is isomorphic to the algebra of all multipli... In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of them.Then,we prove that every Heyting algebra is isomorphic to the algebra of all multiplicative derivations and show that every Boolean algebra is isomorphic to the algebra of all implicative derivations.Finally,we show that the sets of multiplicative and implicative derivations on bounded regular idempotent semihoops are in oneto-one correspondence. 展开更多
关键词 (prelinear)semihoop DERIVATION Heyting algebra Galois connection
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The Role of Music Therapy in Supporting Intellectually Disabled Youth in Senegal
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作者 Raymond Birane Youm Kadidiatou Diarra +1 位作者 Mathias Pouye Jean Augustin Diégane Tine 《Health》 2024年第5期521-534,共14页
Introduction: Music therapy is a practice for helping and supporting people with intellectual and relational difficulties. This study illustrated the benefits of music therapy for young people living with intellectual... Introduction: Music therapy is a practice for helping and supporting people with intellectual and relational difficulties. This study illustrated the benefits of music therapy for young people living with intellectual disabilities (YLID) in an African context. Methodology: This study investigated six young individuals with intellectual disabilities who had undergone three years of music therapy. They were participants in the inclusive non-academic training program at the National School of Arts in Dakar from 2017 to 2019. Data collection utilized individual interviews with the youths, evaluation grids from teachers and psychiatrists. Guardians provided informed consent along with the assent of the young participants. Results: The six young were aged between 18 and 30 years old, with an average age of 24.6 years. Four of the YLID were male. Three young people with intellectual disabilities had delayed psychomotor development. Observations revealed the beneficial influence of music therapy on the health and well-being of young individuals. Music played a role in alleviating stress and anxiety among youth with intellectual disabilities (YLID), enhancing their mood and mental health. It assisted in navigating challenging situations and heightened alertness among YLID. Additionally, music therapy contributed to improvements in dyslexia, fine and gross motor skills, and memory development among intellectually disabled youth, ultimately facilitating their integration into society. Conclusion: In light of our results, music therapy makes a major contribution to the empowerment of YLID. Engaging in musical activities helps young people connect with others through instrumental expression and a sense of accomplishment. By facilitating music therapy, it becomes possible to combat discrimination and stigmatization, thus promoting the social inclusion of intellectually disabled youth. Therefore, it is important to promote music therapy in Senegal to meet the needs of YLID. 展开更多
关键词 Music Therapy YOUNG Intellectual Disabilities Senegal
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Determination of Latent Heats of Vaporization and Fusion
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作者 Lahbib Abbas Lahcen Bih +3 位作者 Khalid Yamni Abderrahim Elyahyaouy Abdelmalik El Attaoui Zahra Ramzi 《Advances in Chemical Engineering and Science》 CAS 2024年第3期113-124,共12页
Water is the most abundant liquid on the surface of the earth. It is a liquid whose properties are quite surprising, both as a pure liquid and as a solvent. Water is a very cohesive liquid: its melting and vaporizatio... Water is the most abundant liquid on the surface of the earth. It is a liquid whose properties are quite surprising, both as a pure liquid and as a solvent. Water is a very cohesive liquid: its melting and vaporization temperatures are very high for a liquid that is neither ionic nor metallic, and whose molar mass is low. Thus, water remains liquid at atmospheric pressure up to 100C while similar molecules such as H2S, H2Se, H2Te for example would give a vaporization temperature close to 80C. This cohesion is in fact ensured by hydrogen bonds between water molecules. This type of bonds between neighboring molecules, hydrogen bonds, is quite often found in chemistry [1] [2]. Any change in the state of aggregation of a substance occurs with the absorption or release of a certain amount of latent heat of transformation. Latent heat of fusion, vaporization or sublimation is the ratio of the energy supplied as heat to the mass of the substance that is melted, vaporized or sublimated. As a result of the reversibility of the processes, the fusion heat is equal to the heat released in the reverse process: crystallization and solidification heat. And likewise the heat of vaporization is equal to the heat of condensation. This equality of heat is often used to determine experimentally either of these quantities. There are two main measurement methods: 1) Direct measurement using the calorimeter, 2) Indirect measure based on the use of the VantHoff relationship. The objective of this work is to measure the latent heat of water vaporization and verify the compatibility of the experimental values with the values given by the tables using the indirect method. 展开更多
关键词 Latent Heat of Vaporization Latent Heat of Fusion CALORIMETRY Relationship of Vant’Hoff
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The Transport and Persistence of Escherichia coli in Leachate from Poultry Litter Amended Soils
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作者 Lorra Belle Hill 《Open Journal of Soil Science》 2024年第4期269-282,共14页
Fecal coliform bacteria such as Escherichia coli (E. coli) are one of the main sources of groundwater pollution. An assessment of the transport and Persistence of E. coli in poultry litter amended Decatur silty Clay s... Fecal coliform bacteria such as Escherichia coli (E. coli) are one of the main sources of groundwater pollution. An assessment of the transport and Persistence of E. coli in poultry litter amended Decatur silty Clay soil and Hartsells Sandy soil was conducted using soil columns and simulated groundwater leaching. Enumeration of initial E. coli was determined to range from 2.851 × 10<sup>3</sup> to 3.044 × 10<sup>3</sup> CFU per gram of soil. These results have been used in a batch study to determine the persistence rate of E. coli in Decatur silty Clay soil and Hartsells Sandy soil. Results prove that E. coli survival growth rate increases for clay soil later than and at a higher rate than sandy soil. The column study has determined that E. coli was transported at a rate of 3.7 × 10<sup>6</sup><sup> </sup>CFU for Decatur silty loam and 6.3 × 10<sup>6</sup><sup> </sup>CFU for Hartsells sandy per gram of soil. Further, linear regression analysis predictions show higher porosity and soil moisture content affect transport, and Hartsells sandy soil has higher transport of E. coli due to its higher porosity and lower volumetric water content. 展开更多
关键词 TRANSPORT LEACHATE PERSISTENCE Poultry Litter E. coli
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Scenario-Based Assessment of the Water-Energy-Food Nexus in Kuwait: Insights for Effective Resource Management
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作者 Amani Al-Adwani Ali Karnib +1 位作者 Alaa Elsadek Waleed Al-Zubari 《Computational Water, Energy, and Environmental Engineering》 2024年第1期38-57,共20页
The interdependency among water, food, and energy (WEF) in the GCC countries is strongly and closely interlinked, and is intensifying as demand for resources increases with population growth and changing consumption p... The interdependency among water, food, and energy (WEF) in the GCC countries is strongly and closely interlinked, and is intensifying as demand for resources increases with population growth and changing consumption patterns, and are expected to be further compounded by the impacts of climate change. Therefore, integrated management of the three sectors is crucial to reduce trade-offs and build synergies among them. This paper presents a comprehensive framework to assess the WEF nexus in Kuwait as a representative case for the GCC countries. The framework consists of three main steps: 1) evaluating the influence of socio-economic development and climate change on water, energy, and food resources;2) generating scenario-based projections;and 3) conducting an extensive quantitative nexus analysis. The WEF interlinkages in Kuwait are modelled quantitatively using the Q-Nexus model, and current critical interdependencies are evaluated. Then, various WEF-Nexus scenarios were conducted for the year 2035 to explore the effects of management interventions in one sector on the other two sectors. The main findings are that per capita municipal water consumption is a major influencer on the WEF-nexus due to the heavy reliance on thermal desalination in municipal water supply in Kuwait, which is attributed to its energy intensity, financial cost, GHGs emissions, and environmental impacts on the marine and air environments. To reduce WEF trade-offs, mitigate risks, and build synergies among the three sectors, it is important to shift the current policy focus on supply-side management approach to the demand-side management and efficiency approaches. 展开更多
关键词 Climate Change Socio-Economic Development Municipal Water Consumption Agricultural Water Consumption Renewable Energy Desalination Technology
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Anti-Melanogenesis Activity of Supercritical Carbon Dioxide Extract from Perilla frutescens Seeds 被引量:1
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作者 Satoshi Suzuki Hitomi Fujisawa +1 位作者 Junpei Abe Ken-ichi Kimura 《Advances in Biological Chemistry》 CAS 2023年第1期42-55,共14页
Perilla frutescens seed (PFS) oil is reported to inhibit skin photoaging;however, its effect on melanogenesis has not yet been investigated. Herein, we tested the anti-melanogenesis activity of an oil-based extract fr... Perilla frutescens seed (PFS) oil is reported to inhibit skin photoaging;however, its effect on melanogenesis has not yet been investigated. Herein, we tested the anti-melanogenesis activity of an oil-based extract from PFS with supercritical carbon dioxide (scCO<sub>2</sub>). In a cell culture system, B16 mouse melanoma cells were treated with the PFS scCO<sub>2</sub> extract and other samples. The PFS scCO<sub>2</sub> extract decreased melanin production by approximately 90% in B16 mouse melanoma cells without cytotoxicity at 100 μg/mL. This effect was greater than that of the well-known melanogenesis inhibitor, kojic acid. Although a hexane-extracted PFS oil and a squeezed PFS oil also decreased melanin production in the B16 cells, the inhibitory effect of the PFS scCO<sub>2</sub> extract was higher than both of these. Chemical analysis of the PFS scCO<sub>2</sub> extract and squeezed PFS oil showed that almost 90% of the components of both oils were α-linolenic acid, linoleic acid, and oleic acid. Furthermore, the ratio of those three fatty acids across both samples was almost the same. When the three fatty acids were mixed in the same ratio as in the PFS scCO<sub>2</sub> extract, the IC<sub>50</sub> of the mixture for melanin production in B16 melanoma cells was identical to that of the PFS scCO<sub>2</sub> extract. However, the IC<sub>50</sub> of the squeezed PFS oil was approximately 6.6 times higher than that of the mixture. Although those fatty acids are the main inhibitory ingredients against melanin production in all of the extracts, some factor(s) in the squeezed PFS reduce their affinity with the cells. These results indicated that the PFS scCO<sub>2</sub> extract could be a superior melanogenesis inhibitor. Although its main ingredients are probably the same as those of the squeezed PFS oil, it is necessary to extract with scCO<sub>2</sub> for stronger anti-melanogenesis activity. 展开更多
关键词 Perilla frutescens MELANOGENESIS Supercritical Carbon Dioxide B16 Mouse Melanoma Cells
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Inheritance and applications of Qu River Arts in Culture Village construction
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作者 Menglin WANG Chujing YUAN 《International Journal of Technology Management》 2014年第12期25-27,共3页
关键词 文化发展 建筑文化 应用 艺术 民族文化 民居风格 文化遗产 文化产业
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Quantitative Analysis of the Effectiveness of Antigen-and Polymerase Chain Reaction-Based Combination Strategies for Containing COVID-19 Transmission in a Simulated Community
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作者 Qiangru Huang Yanxia Sun +6 位作者 Mengmeng Jia Ting Zhang Fangyuan Chen Mingyue Jiang Qing Wang Luzhao Feng Weizhong Yang 《Engineering》 SCIE EI CAS CSCD 2023年第9期234-242,共9页
The number of coronavirus disease 2019(COVID-19)cases continues to surge,overwhelming healthcare systems and causing excess mortality in many countries.Testing of infectious populations remains a key strategy to conta... The number of coronavirus disease 2019(COVID-19)cases continues to surge,overwhelming healthcare systems and causing excess mortality in many countries.Testing of infectious populations remains a key strategy to contain the COVID-19 outbreak,delay the exponential spread of the disease,and flatten the epidemic curve.Using the Omicron variant outbreak as a background,this study aimed to evaluate the effectiveness of testing strategies with different test combinations and frequencies,analyze the factors associated with testing effectiveness,and optimize testing strategies based on these influencing factors.We developed a stochastic,agent-based,discrete-time susceptible–latent–infectious–recovered model simulating a community to estimate the association between three levels of testing strategies and COVID-19 transmission.Antigen testing and its combination strategies were more efficient than polymerase chain reaction(PCR)-related strategies.Antigen testing also showed better performance in reducing the demand for hospital beds and intensive care unit beds.The delay in the turnaround time of test results had a more significant impact on the efficiency of the testing strategy compared to the detection limit of viral load and detection-related contacts.The main advantage of antigen testing strategies is the short turnaround time,which is also a critical factor to be optimized to improve PCR strategies.After modifying the turnaround time,the strategies with less frequent testing were comparable to daily testing.The choice of testing strategy requires consideration of containment goals,test efficacy,community prevalence,and economic factors.This study provides evidence for the selection and optimization of testing strategies in the post-pandemic era and provides guidance for optimizing healthcare resources. 展开更多
关键词 COVID-19 Antigen testing PCR testing Testing strategies
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Lower risk of male infanticide in multilevel primate societies
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作者 Yi-Lin Xiang Yang Yu +1 位作者 Hui-Juan Pan Ming Li 《Zoological Research》 SCIE CAS CSCD 2023年第2期370-373,共4页
DEAR EDITOR,Male infanticide is considered a severe manifestation of sexual conflict in non-human primates during male takeover or male dominance changes. Males engaging in infanticide may obtain fitness benefits, but... DEAR EDITOR,Male infanticide is considered a severe manifestation of sexual conflict in non-human primates during male takeover or male dominance changes. Males engaging in infanticide may obtain fitness benefits, but at the cost of female reproductive outcomes. Consequently, females have developed various anti-infanticide counterstrategies, such as coalitions, dispersal. 展开更多
关键词 dispersal LOWER changes.
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Gravitational wave echoes from strange quark stars in the equation of state with density-dependent quark masses
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作者 Jian‑Feng Xu Lei Cui +2 位作者 Zhen‑Yan Lu Cheng‑Jun Xia Guang‑Xiong Peng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第11期112-119,共8页
According to the recent studies,the gravitational wave(GW)echoes are expected to be generated by quark stars composed of ultrastiff quark matter.The ultrastiff equations of state(EOS)for quark matter were usually obta... According to the recent studies,the gravitational wave(GW)echoes are expected to be generated by quark stars composed of ultrastiff quark matter.The ultrastiff equations of state(EOS)for quark matter were usually obtained either by a simple bag model with artificially assigned sound velocity or by employing interacting strange quark matter(SQM)depicted by simple reparameterization and rescaling.In this study,we investigate GW echoes with EOSs for SQM in the framework of the equivparticle model with density-dependent quark masses and pairing effects.We conclude that strange quark stars(SQSs)can be sufficiently compact to possess a photon sphere capable of generating GW echoes with frequencies in the range of approximately 20 kHz.However,SQSs cannot account for the observed 72 Hz signal in GW170817 event.Furthermore,we determined that quark-pairing effects play a crucial role in enabling SQSs to satisfy the necessary conditions for producing these types of echoes. 展开更多
关键词 Strange quark star Gravitational wave echoes Color-flavour-locked phase Strange quark matter
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Specific Heat Capacity of A2FeCoO6-δ (A = Ca or Sr)
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作者 S’Nya Sanchez Mandy Guinn +2 位作者 Uttam S. Phuyal Gurjot S. Dhaliwal Ram Krishna Hona 《Journal of Materials Science and Chemical Engineering》 CAS 2023年第4期1-10,共10页
A<sub>2</sub>FeCoO<sub>6-δ</sub> (A = Ca or Sr) is synthesized by the solid-state synthesis method and their specific heat capacities are evaluated at 40˚C using a heat flow meter. The effect ... A<sub>2</sub>FeCoO<sub>6-δ</sub> (A = Ca or Sr) is synthesized by the solid-state synthesis method and their specific heat capacities are evaluated at 40˚C using a heat flow meter. The effect of the A-cation size on the specific heat capacity of these compounds is observed. The specific heat capacity of Sr<sub>2</sub>FeCoO<sub>6-δ</sub> is found to be the highest, and that of Ca<sub>2</sub>FeCoO<sub>6-δ</sub> is the lowest while CaSrFeCoO<sub>6-δ</sub> shows the intermediate value. The specific heat capacity decreases with the decrease of the average A-site ionic radius, demonstrating the relationship between heat capacity and A-site ionic radius. The relationship between specific heat capacity and molar mass is also confirmed as the δ value decreases or molar mass increases from Ca<sub>2</sub>FeCoO<sub>6-δ</sub> to CaSrFeCoO<sub>6-δ</sub> to Sr<sub>2</sub>FeCoO<sub>6-δ</sub>. 展开更多
关键词 Perovskite Oxide Specific Heat Capacity Oxygen Vacancy XRD Vacancy Order
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Characteristics and C-E Translation Methods of the Four-Character Frame in the Subtitles of the Documentary Daming Palace
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作者 Junqi Jiang 《Open Journal of Applied Sciences》 CAS 2023年第3期424-430,共7页
This paper studies the four-character frame in the subtitle of the documentary Daming Palace, aiming to provide a reference for the translation of the documentary four-character case as well as better spread Chinese c... This paper studies the four-character frame in the subtitle of the documentary Daming Palace, aiming to provide a reference for the translation of the documentary four-character case as well as better spread Chinese culture. By analyzing, researching and summarizing the subtitle of Daming Palace and reading a lot of literature, the author has found that in Daming Palace the four-character frame is characterized by the use of the absolute four-character frames and the recurrence of some four-character frames, and that C-E translation methods of the four-character frame are mainly literal translation, free translation, provincial translation and concise translation. 展开更多
关键词 Documentary Subtitles Four-Character Frame English Translation
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Systematic Method for Constructing Lewis Representations
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作者 Lahbib Abbas Lahcen Bih +3 位作者 Khalid Yamni Abderrahim Elyahyaouy Abdelmalik El Attaoui Zahra Ramzi 《Open Journal of Inorganic Chemistry》 2024年第1期1-18,共18页
The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bon... The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bond. Using a number of rules in a defined order, it is often better suited to complicated cases than the Lewis representation of atoms. This method allows us to determine the formal charge and oxidation number of each atom in the edifice more efficiently than other methods. 展开更多
关键词 Systematic Method Lewis Representation Chemical Bond Formal Charge Oxidation Number
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Graphite Carbone Structure
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作者 Lahbib Abbas Lahcen Bih +3 位作者 Khalid Yamni Abderrahim Elyahyaouy Abdelmalik El Attaoui Zahra Ramzi 《Crystal Structure Theory and Applications》 2024年第1期1-10,共10页
Carbon graphite is a crystalline form of carbon consisting of layers of hexagonal carbon atoms arranged in a two-dimensional “graphene” structure. Graphene layers are stacked on top of each other, forming a three-di... Carbon graphite is a crystalline form of carbon consisting of layers of hexagonal carbon atoms arranged in a two-dimensional “graphene” structure. Graphene layers are stacked on top of each other, forming a three-dimensional structure with a high degree of anisotropy. The carbon atoms within each layer are linked together by strong covalent bonds, creating a strong, stable lattice structure. However, the layers themselves are held together by weak van der Waals forces, enabling them to slide easily over each other. The properties of carbon graphite are highly dependent on the orientation and alignment of the graphene layers. When the layers are aligned parallel to each other, the material exhibits high strength and stiffness along the alignment direction, but is weaker and more flexible in other directions. Carbon graphite is used in a variety of applications where high strength, rigidity and electrical conductivity are required. Some common applications include electrical contacts, electric motor brushes, and as a structural material in aerospace and defense applications. The aim of our work is to describe the structure of graphite, its physical and chemical properties and its applications. 展开更多
关键词 GRAPHITE GRAPHENE Hexagonal Structure HARDNESS RIGIDITY Electrical Con-ductivity
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Mechanisms of neuroplasticity and brain degeneration: strategies for protection during the aging process 被引量:9
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作者 Mariana Toricelli Arthur Antonio Ruiz Pereira +4 位作者 Guilherme Souza Abrao Helena Nascimento Malerba Julia Maia Hudson Sousa Buck Tania Araujo Viel 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第1期58-67,共10页
Aging is a dynamic and progressive process that begins at conception and continues until death.This process leads to a decrease in homeostasis and morphological,biochemical and psychological changes,increasing the ind... Aging is a dynamic and progressive process that begins at conception and continues until death.This process leads to a decrease in homeostasis and morphological,biochemical and psychological changes,increasing the individual’s vulnerability to various diseases.The growth in the number of aging populations has increased the prevalence of chronic degenerative diseases,impairment of the central nervous system and dementias,such as Alzheimer’s disease,whose main risk factor is age,leading to an increase of the number of individuals who need daily support for life activities.Some theories about aging suggest it is caused by an increase of cellular senescence and reactive oxygen species,which leads to inflammation,oxidation,cell membrane damage and consequently neuronal death.Also,mitochondrial mutations,which are generated throughout the aging process,can lead to changes in energy production,deficiencies in electron transport and apoptosis induction that can result in decreased function.Additionally,increasing cellular senescence and the release of proinflammatory cytokines can cause irreversible damage to neuronal cells.Recent reports point to the importance of changing lifestyle by increasing physical exercise,improving nutrition and environmental enrichment to activate neuroprotective defense mechanisms.Therefore,this review aims to address the latest information about the different mechanisms related to neuroplasticity and neuronal death and to provide strategies that can improve neuroprotection and decrease the neurodegeneration caused by aging and environmental stressors. 展开更多
关键词 cell senescence cell signaling CHOLINERGIC enriched environment long-term potentiation NEURODEGENERATION NEUROGENESIS neuroinflammatory neuronal death NEUROPROTECTION neurotophin
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Spatial and temporal variability in vegetation cover of Mongolia and its implications 被引量:4
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作者 Sumiya VANDANDORJ Batdelger GANTSETSEG Bazartseren BOLDGIV 《Journal of Arid Land》 SCIE CSCD 2015年第4期450-461,共12页
In this paper, we attempted to determine the most stable or unstable regions of vegetation cover in Mongolia and their spatio-temporal dynamics using Terra/MODIS Normalized Difference Vegetation Index (NDVI) dataset... In this paper, we attempted to determine the most stable or unstable regions of vegetation cover in Mongolia and their spatio-temporal dynamics using Terra/MODIS Normalized Difference Vegetation Index (NDVI) dataset, which had a 250-m spatial resolution and comprised 6 periods of 16-day composited temporal resolution data (from 10 June to 13 September) for summer seasons from 2000 to 2012. We also used precipitation data as well as biomass data from 12 meteorological stations located in 4 largest natural zones of Mongolia. Our study showed that taiga and forest steppe zones had relatively stable vegetation cover because of forest characteristics and relatively high precipitation. The highest coefficient of variation (CV) of vegetation cover occurred frequently in the steppe and desert steppe zones, mainly depending on variation of precipitation. Our results showed that spatial and temporal variability in vegetation cover (NDVI or plant biomass) of Mongolia was highly dependent on the amount, distribution and CV of precipitation. This suggests that the lowest inter-annual CV of NDVI can occur dur- ing wet periods of growing season or in high precipitation regions, while the highest inter-annual CV of NDVI can occur during dry periods and in low precipitation regions. Although the desert zone received less precipitation than other natural zones of the country, it had relatively low variation compared to the steppe and desert steppe, which could be attributed to the very sparse vegetation in the desert. 展开更多
关键词 vegetation cover MODIS NDVI natural zones seasonal dynamics STABILITY Mongolia
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