Affective factors and cognitive factors are two important parts of English learning, However, English teaching in recent years have taken into special consideration the necessity of knowledge and intelligence and comp...Affective factors and cognitive factors are two important parts of English learning, However, English teaching in recent years have taken into special consideration the necessity of knowledge and intelligence and comparatively ignored the development of affection. It may greatly reduce students＇ English learning capacity and limit the whole development of students. This paper will discuss the definition and the importance of affection and some main affective factors, and illustrate some implications of how to implement practical affective activities.展开更多
The new curriculum standard points out that affection is one of the most important goals of fundamental education. The non-target language environment is easier to cause the affective change of middle school students ...The new curriculum standard points out that affection is one of the most important goals of fundamental education. The non-target language environment is easier to cause the affective change of middle school students who are changeable in their affective state. Based on the affective filter hypothesis, this paper deals with the adjustment to affective factors in English learning by using Internet English Curriculum Resource, such as attitude and motivation, anxiety and inhibition, self-esteem and self-confidence. At last, some suggestions are offered to judge Internet English Curriculum Resource.展开更多
In foreign language teaching, there appear a lot of approaches. This essay lays special stress on humanistic approach and analyses the influence of some important affective factors on language learning, for the purpos...In foreign language teaching, there appear a lot of approaches. This essay lays special stress on humanistic approach and analyses the influence of some important affective factors on language learning, for the purpose of inviting teachers＇ attention to students＇ emotions in fulfilling their teaching task.展开更多
Second language acquisition is a complex psychological process which comprises acquirement of phonetics,vocabulary,grammar and many unacquainted points.Facing a new linguistic system that represents a different cultur...Second language acquisition is a complex psychological process which comprises acquirement of phonetics,vocabulary,grammar and many unacquainted points.Facing a new linguistic system that represents a different culture and a novel way of thinking,the learners have to work hard to cross the boundary of language for mastering it.This needs not only a simple literal course,but also a psychological one that mainly refers to sensations,attitudes and mood which are called the affective factors.This essay aims at discussing the related affective factors in second language acquisition that may have a positive or negative impact on the effect of mastering a second language for learners because the positive emotions can play an effective role in language learning practice of quickening the language acquisition while the negative emotions are a hindrance of mental perception,comprehension,and memory function.Thus,applying those positive affective factors during the process is a vital way to help learners study English effectively.展开更多
Language learning is a complicated process which is influenced by many factors,including cognitive factors,environmental factors and affective factors.The importance of affective factors in language learning has gaine...Language learning is a complicated process which is influenced by many factors,including cognitive factors,environmental factors and affective factors.The importance of affective factors in language learning has gained increasing attention in recent years.Based on the affective filter hypothesis(Krashen,1985),this study mainly investigates four important affective factors,namely,attitude,character,inhibition,and teacher-student empathy.Through a questionnaire survey,this study analyzes the current situation of learning affections of high school and college students,and compares their influence on second language acquisition.The results show that attitude,inhibition,and teacher-student empathy affected high school students more than college students,and character affected neither high school students nor college students.The results provide some implications for English teaching.展开更多
Recent years has witnessed the great efforts made to investigate the relationship between language and affective factors. This essay serves both to focus awareness on the role of affective factors in the communicative...Recent years has witnessed the great efforts made to investigate the relationship between language and affective factors. This essay serves both to focus awareness on the role of affective factors in the communicative classroom and to show how affective factors influence many different aspects of communicative language teaching/learning. A survey is also conducted on the communicative language teaching to illustrate affective factors in the communicative classroom.展开更多
Affective factors are the meaning of"decisive essence "in foreign language learning. Adult foreign language learning is much influenced by affective factors than children language development in the process ...Affective factors are the meaning of"decisive essence "in foreign language learning. Adult foreign language learning is much influenced by affective factors than children language development in the process of language development. In this paper, on the basis of a Krashen's"Affective Filter Hypothesis", the writer analyses the reasons, and analyses adult foreign language learning and child language development affect differently from four main affective factors: motivation, self-confidence,anxiety and empathy.展开更多
More than 5000 landslides or potential landslides have been triggered in the Three Gorges Reservoir(TGR)area since the impoundment in 2003.This study aims at investigating the reservoirinduced landslides spatiotempora...More than 5000 landslides or potential landslides have been triggered in the Three Gorges Reservoir(TGR)area since the impoundment in 2003.This study aims at investigating the reservoirinduced landslides spatiotemporal and size distribution and its influence factors in the TGR by taking 790 landslides as statistical samples.The landslides exhibit significant regional and sub-regional spatial differences,and numerous landslides occurred at the initial three impoundment stages and the corresponding 2-3 cycles of reservoir operations followed,but the landslide frequency decreased dramatically after 2010 from temporal perspective.The relationship between landslide development and topographical,geological as well as hydrological factors were analyzed qualitatively.The reservoir-induced landslides in TGR area exhibit self-organized criticality and the rollover is nearly 2.5×10^(4) m^(2),which could not be attributed to the missing data but the coupled influences imposed by affecting factors.Both the double Pareto and inverse gamma functions are more suitable than the power-law function to present the landslide size characteristics.In term of the fitting precious,the adaptability of the inverse gamma function is better if the landslide inventories are limited.The research results provide foundation for the landslide susceptibility maps and hazard risk assessment.展开更多
Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient ele...Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter.展开更多
Ocean energy has progressively gained considerable interest due to its sufficient potential to meet the world’s energy demand,and the blade is the core component in electricity generation from the ocean current.Howev...Ocean energy has progressively gained considerable interest due to its sufficient potential to meet the world’s energy demand,and the blade is the core component in electricity generation from the ocean current.However,the widened hydraulic excitation frequency may satisfy the blade resonance due to the time variation in the velocity and angle of attack of the ocean current,even resulting in blade fatigue and destructively interfering with grid stability.A key parameter that determines the resonance amplitude of the blade is the hydrodynamic damping ratio(HDR).However,HDR is difficult to obtain due to the complex fluid-structure interaction(FSI).Therefore,a literature review was conducted on the hydrodynamic damping characteristics of blade-like structures.The experimental and simulation methods used to identify and obtain the HDR quantitatively were described,placing emphasis on the experimental processes and simulation setups.Moreover,the accuracy and efficiency of different simulation methods were compared,and the modal work approach was recommended.The effects of key typical parameters,including flow velocity,angle of attack,gap,rotational speed,and cavitation,on the HDR were then summarized,and the suggestions on operating conditions were presented from the perspective of increasing the HDR.Subsequently,considering multiple flow parameters,several theoretical derivations and semi-empirical prediction formulas for HDR were introduced,and the accuracy and application were discussed.Based on the shortcomings of the existing research,the direction of future research was finally determined.The current work offers a clear understanding of the HDR of blade-like structures,which could improve the evaluation accuracy of flow-induced vibration in the design stage.展开更多
With the development of basic education, higher vocational education has gradually attracted attention from all walks of life. At present, higher vocational public English classes play an important role in higher voca...With the development of basic education, higher vocational education has gradually attracted attention from all walks of life. At present, higher vocational public English classes play an important role in higher vocational public English education. Higher vocational English teachers' teaching quality and teaching methods also determine the quality of teaching. If higher vocational public English teachers want to happily complete the teaching tasks, complete English teaching in happy teaching and improve students' learning results;it is necessary to pay attention to the injection of emotional factors in teaching and break the traditional teaching model. This paper mainly studies the current situation of public English teaching in higher vocational colleges, studies the problems existing in public English interesting teaching in higher vocational colleges, and puts forward some countermeasures for public English interesting teaching in higher vocational colleges.展开更多
To change the undesirable present situation of recovering and using converter gas in steel plants in China, the basic approaches to improving the converter gas recovery rate were analyzed theoretically along with the ...To change the undesirable present situation of recovering and using converter gas in steel plants in China, the basic approaches to improving the converter gas recovery rate were analyzed theoretically along with the change curves of the converter gas component content, based on the converter gas recovery system of Baosteel No. 2 steel- making plant. The effects of converter device, raw material, air imbibed quantity, recovery restricted condition, and intensity of oxygen blowing on the converter gas recovery rate were studied. Among these, the effects of the air im bibed quantity, recovery restricted condition, and intensity of oxygen blowing are remarkable. Comprehensive measures were put forward for improving the converter gas recovery from the point of devices, etc. , and good results were achieved.展开更多
This research examines the distribution features of 4960 caves across Guizhou Province, while probing the relationship between the caves＇ spatial patterns and geographic elements. This study is based on hydrogeologic...This research examines the distribution features of 4960 caves across Guizhou Province, while probing the relationship between the caves＇ spatial patterns and geographic elements. This study is based on hydrogeological and topographic maps of Guizhou. ArcGIS software was used to process the adjacent index, spatial analysis, and coupling analysis of the caves altitude and longitude, as well as the rock properties, lithology, drainage and tec- tonic division of almost 5000 caves. Based on a point pattern analysis of Guizhou caves, the adjacent index is 0.53, and the coefficient of variation verified by Tyson polygon reached 72.469%. This figure reflects the clustered distribution pattern of the caves. Across the entire province, caves are divided into four concentrated areas and one weakly affected area. The four concentrated areas are Zunyi-Tongren, Bijie, Qianxinan-Liupanshui, and Gui- yang-Anshun-Qinan. The one weakly affected zone is Qiandongnan. The most concentrated among them is the Guiyang-Anshun-Qiannan area, which covers 24.67% of the total province area, and accounts for 36.63% of the total province＇s caves. Cave distribution in Guizhou is characterized as dense in the western part and sparse in the eastern part. Under this study background, the natural elements of formation, including lithology, structure, climate, hydrol- ogy, and altitude, and their effects on the distribution, number, and spatial pattern of cave development is analyzed.展开更多
Based on field survey, the thesis analyzes the key factors affecting development of rural tourism systematically, taking Chengdu as an example. These factors include regional e-conomic development level & leisure ...Based on field survey, the thesis analyzes the key factors affecting development of rural tourism systematically, taking Chengdu as an example. These factors include regional e-conomic development level & leisure tradition, tourist market & traffic, tourist resource, spatial agglomeration and competition of rural tourism, and decision-making behavior. Among them, regional economic development level & leisure tradition and tourist market & traffic are prerequisites for the development of rural tourism which have an impact on tourist' s consumption level, consumption custom, operator's investment ability, tourist destination distribution and scale; Tourist resource, spatial agglomeration and competition of rural tourism are restrictive conditions affecting character and distribution of rural tourism; Government's decision-making behavior is of importance for expansion of scale and popularity of regional rural tourism, meanwhile, operators' decision-making behavior includes investment scale and operational strategies, and for operators from the outside, location selection is included additionally. All these decision-making behaviors are subjective conditions for the development of rural tourism.展开更多
In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When...In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning.展开更多
The nano intercalation compounding of wood and MMT has important implications for the modification of wood and for the development of new materials. With water-soluble phenol formaldehyde resin as an intermediary, the...The nano intercalation compounding of wood and MMT has important implications for the modification of wood and for the development of new materials. With water-soluble phenol formaldehyde resin as an intermediary, the nanocomposites of Chinese fir （Cunningharnia lanceolata） wood and montmorillonite （MMT） were prepared via three impregnation methods, i.e. normal pressure, once and twice vacuum methods. Based on the weight percent gain （WPG） of impregnated wood, the effects of compounding wood and MMT in terms of concentration, impregnating temperature and time, wood moisture content and wood extraction treatments, on sapwood and heartwood are discussed. Results show that： 1） the optimum MMT concentration in the impregnation solution is 3% for sapwood and 5% for heartwood; 2） room temperature is suitable in practice; 3） treatment pressure should be set at a high enough value in order to ensure sufficient permeation; 4） the effects of different impregnation methods on sapwood and heartwood are different, the heartwood extractives affect WPG significantly; cell wall permeability of sapwood is better than that of heartwood; 5） the cold water, hot water and benzene-ethanol solution extractions can all greatly improve the permeability of heartwood, hot water can dissolve some hemicellulose of low aggregation and hot water extraction improves wood cell wall permeability; 6） with an increase in wood moisture content, the permeable space in wood is reduced, but with a certain amount of water, instantaneous spaces are created and the permeation dynamic increases. This effect is especially apparent for difficult impregnating situations in heartwood and impregnation under normal pressure.展开更多
文摘Affective factors and cognitive factors are two important parts of English learning, However, English teaching in recent years have taken into special consideration the necessity of knowledge and intelligence and comparatively ignored the development of affection. It may greatly reduce students＇ English learning capacity and limit the whole development of students. This paper will discuss the definition and the importance of affection and some main affective factors, and illustrate some implications of how to implement practical affective activities.
文摘The new curriculum standard points out that affection is one of the most important goals of fundamental education. The non-target language environment is easier to cause the affective change of middle school students who are changeable in their affective state. Based on the affective filter hypothesis, this paper deals with the adjustment to affective factors in English learning by using Internet English Curriculum Resource, such as attitude and motivation, anxiety and inhibition, self-esteem and self-confidence. At last, some suggestions are offered to judge Internet English Curriculum Resource.
文摘In foreign language teaching, there appear a lot of approaches. This essay lays special stress on humanistic approach and analyses the influence of some important affective factors on language learning, for the purpose of inviting teachers＇ attention to students＇ emotions in fulfilling their teaching task.
文摘Second language acquisition is a complex psychological process which comprises acquirement of phonetics,vocabulary,grammar and many unacquainted points.Facing a new linguistic system that represents a different culture and a novel way of thinking,the learners have to work hard to cross the boundary of language for mastering it.This needs not only a simple literal course,but also a psychological one that mainly refers to sensations,attitudes and mood which are called the affective factors.This essay aims at discussing the related affective factors in second language acquisition that may have a positive or negative impact on the effect of mastering a second language for learners because the positive emotions can play an effective role in language learning practice of quickening the language acquisition while the negative emotions are a hindrance of mental perception,comprehension,and memory function.Thus,applying those positive affective factors during the process is a vital way to help learners study English effectively.
文摘Language learning is a complicated process which is influenced by many factors,including cognitive factors,environmental factors and affective factors.The importance of affective factors in language learning has gained increasing attention in recent years.Based on the affective filter hypothesis(Krashen,1985),this study mainly investigates four important affective factors,namely,attitude,character,inhibition,and teacher-student empathy.Through a questionnaire survey,this study analyzes the current situation of learning affections of high school and college students,and compares their influence on second language acquisition.The results show that attitude,inhibition,and teacher-student empathy affected high school students more than college students,and character affected neither high school students nor college students.The results provide some implications for English teaching.
文摘Recent years has witnessed the great efforts made to investigate the relationship between language and affective factors. This essay serves both to focus awareness on the role of affective factors in the communicative classroom and to show how affective factors influence many different aspects of communicative language teaching/learning. A survey is also conducted on the communicative language teaching to illustrate affective factors in the communicative classroom.
文摘Affective factors are the meaning of"decisive essence "in foreign language learning. Adult foreign language learning is much influenced by affective factors than children language development in the process of language development. In this paper, on the basis of a Krashen's"Affective Filter Hypothesis", the writer analyses the reasons, and analyses adult foreign language learning and child language development affect differently from four main affective factors: motivation, self-confidence,anxiety and empathy.
基金supported by the National Natural Science Foundation of China(Nos.42277187,42407279)the United Key Program of the National Natural Sciences Foundation of China(No.U23A202579)+4 种基金Hebei Provincial Natural Science Foundation(No.D2021202002)Hunan Provincial Natural Science Foundation(No.2022JJ40521)Changsha Municipal Natural Science Foundation(No.kq2202065)the Open Research Fund Program of Hunan Provincial Key Laboratory for Big Data Smart Application of Natural Disaster Risks Survey of Highway Engineering(No.BNH2024KFB04)the Conselleria de Innovación,Universidades,Ciencia y Sociedad Digital(No.CIAICO/2021/335)to Roberto Tomás。
文摘More than 5000 landslides or potential landslides have been triggered in the Three Gorges Reservoir(TGR)area since the impoundment in 2003.This study aims at investigating the reservoirinduced landslides spatiotemporal and size distribution and its influence factors in the TGR by taking 790 landslides as statistical samples.The landslides exhibit significant regional and sub-regional spatial differences,and numerous landslides occurred at the initial three impoundment stages and the corresponding 2-3 cycles of reservoir operations followed,but the landslide frequency decreased dramatically after 2010 from temporal perspective.The relationship between landslide development and topographical,geological as well as hydrological factors were analyzed qualitatively.The reservoir-induced landslides in TGR area exhibit self-organized criticality and the rollover is nearly 2.5×10^(4) m^(2),which could not be attributed to the missing data but the coupled influences imposed by affecting factors.Both the double Pareto and inverse gamma functions are more suitable than the power-law function to present the landslide size characteristics.In term of the fitting precious,the adaptability of the inverse gamma function is better if the landslide inventories are limited.The research results provide foundation for the landslide susceptibility maps and hazard risk assessment.
基金Supported by a Sub-project "Ecological Geochemical Survey of Oil Crop (sunflower) Producing Area in Western Jilin" of the Project of China Geological Survey and Jilin Provincial Government " Agricul-tural Geological Survey of Jilin Province"~~
文摘Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter.
基金Supported by the National Natural Science Foundation of China(Nos.52222904 and 52309117)China Postdoctoral Science Foundation(Nos.2022TQ0168 and 2023M731895).
文摘Ocean energy has progressively gained considerable interest due to its sufficient potential to meet the world’s energy demand,and the blade is the core component in electricity generation from the ocean current.However,the widened hydraulic excitation frequency may satisfy the blade resonance due to the time variation in the velocity and angle of attack of the ocean current,even resulting in blade fatigue and destructively interfering with grid stability.A key parameter that determines the resonance amplitude of the blade is the hydrodynamic damping ratio(HDR).However,HDR is difficult to obtain due to the complex fluid-structure interaction(FSI).Therefore,a literature review was conducted on the hydrodynamic damping characteristics of blade-like structures.The experimental and simulation methods used to identify and obtain the HDR quantitatively were described,placing emphasis on the experimental processes and simulation setups.Moreover,the accuracy and efficiency of different simulation methods were compared,and the modal work approach was recommended.The effects of key typical parameters,including flow velocity,angle of attack,gap,rotational speed,and cavitation,on the HDR were then summarized,and the suggestions on operating conditions were presented from the perspective of increasing the HDR.Subsequently,considering multiple flow parameters,several theoretical derivations and semi-empirical prediction formulas for HDR were introduced,and the accuracy and application were discussed.Based on the shortcomings of the existing research,the direction of future research was finally determined.The current work offers a clear understanding of the HDR of blade-like structures,which could improve the evaluation accuracy of flow-induced vibration in the design stage.
文摘With the development of basic education, higher vocational education has gradually attracted attention from all walks of life. At present, higher vocational public English classes play an important role in higher vocational public English education. Higher vocational English teachers' teaching quality and teaching methods also determine the quality of teaching. If higher vocational public English teachers want to happily complete the teaching tasks, complete English teaching in happy teaching and improve students' learning results;it is necessary to pay attention to the injection of emotional factors in teaching and break the traditional teaching model. This paper mainly studies the current situation of public English teaching in higher vocational colleges, studies the problems existing in public English interesting teaching in higher vocational colleges, and puts forward some countermeasures for public English interesting teaching in higher vocational colleges.
基金Item Sponsored by National Natural Science Foundation of China (50334020)
文摘To change the undesirable present situation of recovering and using converter gas in steel plants in China, the basic approaches to improving the converter gas recovery rate were analyzed theoretically along with the change curves of the converter gas component content, based on the converter gas recovery system of Baosteel No. 2 steel- making plant. The effects of converter device, raw material, air imbibed quantity, recovery restricted condition, and intensity of oxygen blowing on the converter gas recovery rate were studied. Among these, the effects of the air im bibed quantity, recovery restricted condition, and intensity of oxygen blowing are remarkable. Comprehensive measures were put forward for improving the converter gas recovery from the point of devices, etc. , and good results were achieved.
基金National Natural Science Foundation of China, No.41361081 High-level Innovative Talents Cultivation Program of Guizhou Province （Qian Ke He SY [201615674） Project of Innovation Program for Postgraduate Education of Guizhou Province, No.[2016]04
文摘This research examines the distribution features of 4960 caves across Guizhou Province, while probing the relationship between the caves＇ spatial patterns and geographic elements. This study is based on hydrogeological and topographic maps of Guizhou. ArcGIS software was used to process the adjacent index, spatial analysis, and coupling analysis of the caves altitude and longitude, as well as the rock properties, lithology, drainage and tec- tonic division of almost 5000 caves. Based on a point pattern analysis of Guizhou caves, the adjacent index is 0.53, and the coefficient of variation verified by Tyson polygon reached 72.469%. This figure reflects the clustered distribution pattern of the caves. Across the entire province, caves are divided into four concentrated areas and one weakly affected area. The four concentrated areas are Zunyi-Tongren, Bijie, Qianxinan-Liupanshui, and Gui- yang-Anshun-Qinan. The one weakly affected zone is Qiandongnan. The most concentrated among them is the Guiyang-Anshun-Qiannan area, which covers 24.67% of the total province area, and accounts for 36.63% of the total province＇s caves. Cave distribution in Guizhou is characterized as dense in the western part and sparse in the eastern part. Under this study background, the natural elements of formation, including lithology, structure, climate, hydrol- ogy, and altitude, and their effects on the distribution, number, and spatial pattern of cave development is analyzed.
基金Supported by the 10th Five-Year Plan Programme Item of Chengdu Philosophy and Social Science Research and the Knowledge Innovation Program of Chinese Academy of Sciences(KZCX2-SW-319-4)
文摘Based on field survey, the thesis analyzes the key factors affecting development of rural tourism systematically, taking Chengdu as an example. These factors include regional e-conomic development level & leisure tradition, tourist market & traffic, tourist resource, spatial agglomeration and competition of rural tourism, and decision-making behavior. Among them, regional economic development level & leisure tradition and tourist market & traffic are prerequisites for the development of rural tourism which have an impact on tourist' s consumption level, consumption custom, operator's investment ability, tourist destination distribution and scale; Tourist resource, spatial agglomeration and competition of rural tourism are restrictive conditions affecting character and distribution of rural tourism; Government's decision-making behavior is of importance for expansion of scale and popularity of regional rural tourism, meanwhile, operators' decision-making behavior includes investment scale and operational strategies, and for operators from the outside, location selection is included additionally. All these decision-making behaviors are subjective conditions for the development of rural tourism.
基金Projects BK2007145 supported by the Jiangsu Natural Science Foundation of China NCET-04-0454 by the Program for New Century Excellent Talentsin Universities
文摘In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning.
基金This study was financially supported by the National Natural Science Foundation of China （Grant No. 30271055）.
文摘The nano intercalation compounding of wood and MMT has important implications for the modification of wood and for the development of new materials. With water-soluble phenol formaldehyde resin as an intermediary, the nanocomposites of Chinese fir （Cunningharnia lanceolata） wood and montmorillonite （MMT） were prepared via three impregnation methods, i.e. normal pressure, once and twice vacuum methods. Based on the weight percent gain （WPG） of impregnated wood, the effects of compounding wood and MMT in terms of concentration, impregnating temperature and time, wood moisture content and wood extraction treatments, on sapwood and heartwood are discussed. Results show that： 1） the optimum MMT concentration in the impregnation solution is 3% for sapwood and 5% for heartwood; 2） room temperature is suitable in practice; 3） treatment pressure should be set at a high enough value in order to ensure sufficient permeation; 4） the effects of different impregnation methods on sapwood and heartwood are different, the heartwood extractives affect WPG significantly; cell wall permeability of sapwood is better than that of heartwood; 5） the cold water, hot water and benzene-ethanol solution extractions can all greatly improve the permeability of heartwood, hot water can dissolve some hemicellulose of low aggregation and hot water extraction improves wood cell wall permeability; 6） with an increase in wood moisture content, the permeable space in wood is reduced, but with a certain amount of water, instantaneous spaces are created and the permeation dynamic increases. This effect is especially apparent for difficult impregnating situations in heartwood and impregnation under normal pressure.
