In order to better understand the thermodynamic properties of magnesium oxysulfate(MOS)cement,pure reagent was analyzed to prepare magnesium sulfide cement,non-isothermal kinetics calculation of the main hydration pro...In order to better understand the thermodynamic properties of magnesium oxysulfate(MOS)cement,pure reagent was analyzed to prepare magnesium sulfide cement,non-isothermal kinetics calculation of the main hydration products was also carried out,and the conversion process of magnesium sulfide cement 517 phase at different temperatures was investigated.Composition of magnesium sulfide cement prepared was measured by XRD technique,and decomposed by a comprehensive thermal analyzer,and DSC curves of magnesium sulfide cement under different temperature rising rates were processed by Kinssinger method and Dolye-Ozawa method.According to the TG-DSC curves of magnesium sulfide cement,the thermal decomposition reaction process can be divided into five stages under normal conditions.The DSC curve was processed by Kinssinger method and Dolye-Ozawa method,and the kinetic analysis was carried out to calculate the 517 phase activation energy of magnesium sulfide cement.The three stages correspond to different activation energies.Therefore,flame retardant mechanism and thermal decomposition mechanism of magnesium sulfide cement based materials are deduced.展开更多
Ecological demonstration area (EDA) is an authorized nomination, which should be assessed from several aspects, including ecological, social, environmental, economic ones and so on. It is difficult to advance an exact...Ecological demonstration area (EDA) is an authorized nomination, which should be assessed from several aspects, including ecological, social, environmental, economic ones and so on. It is difficult to advance an exact developing level index of EDA due to its indicator system’s complexity and disequilibrium. In this paper, a framework of indicators was set to evaluate, monitor and examine the comprehensive level of ecological demonstration area (EDA). Fuzzy logic method was used to develop the fuzzy comprehensive evaluation model (FCEM), which could quantitatively reveal the developing degree of EDA. Huiji District of Zhengzhou, Henan Province, one of the 9th group of national EDAs, was taken as a study case. The framework of FCEM for the integrated system included six subsystems, which were social, economic, ecological, rural, urban and accessorial description ones. The research would be valuable in the comprehensive quantitative evaluation of EDA and would work as a guide in the construction practices of Huiji ecological demonstration area.展开更多
In the context of accelerated development of the Silk Road Economic Belt,it is necessary to conduct in-depth research on urbanization of Central Asian countries.This paper analyzes the spatial and temporal patterns an...In the context of accelerated development of the Silk Road Economic Belt,it is necessary to conduct in-depth research on urbanization of Central Asian countries.This paper analyzes the spatial and temporal patterns and evolution dynamics of urbanization during the period 1991-2017 from the perspective of internal-external forces.The results are as follows.(1)The urbanization process of the five Central Asian countries studied is significantly influenced by their political and economic situations and displays periodic characteristics.All five countries experienced a stagnation development stage at the beginning of independence,and then a rapid growth stage since the year 2000.The average annual growth rates of the two stages were 0.19% and 1.45%,respectively.(2)Differences in the urbanization of the studied countries are obvious,and the evolutionary characteristics of each subsystem of urbanization are different.It is therefore necessary to distinguish and clearly understand the urbanization process of each country.(3)Internal and external factors play a role in the urbanization processes of Central Asian countries.External railway transportation facilities are particularly important for the development of urbanization in these countries.The regression coefficients of railway construction length,total merchandise trade and actually utilized foreign capital are 0.5665,0.0937 and 0.0806,respectively.(4)Countries with smaller populations and economic scales need to engage in international cooperation to promote healthy development of urbanization.The results of the study indicate that internal and external factors work together in the urbanization process of Central Asian countries,and external forces are particularly important for the development of such urbanization.展开更多
Indicators are the basis for judging the working performance of exhaust hood and capture performance are usually used as the only indicator.An evaluation index system including three factors of cooking oil fumes(COF)i...Indicators are the basis for judging the working performance of exhaust hood and capture performance are usually used as the only indicator.An evaluation index system including three factors of cooking oil fumes(COF)instantaneous capture,health risk impact and thermal comfort was proposed to assess the comprehensive performance of exhaust hood in the present study.The primary capture efficiency(PCE)of formaldehyde,the PCE of particulate matter with the diameter less than or equal to 2.5μm(PM_(2.5)),the incremental lifetime cancer risk(ILCR)of formaldehyde,the ILCR of PM_(2.5)and the predicted mean vote(PMV),which can all be quantified with the aid of computational fluid dynamics(CFD),were selected as the indicators.And the analytic hierarchy process(AHP)method was introduced to perform the comprehensive performance evaluation of exhaust hood.The performance of two exhaust hood structures(grille and orifice type)with three exhaust rates(3000,4000,and 5000 m^(3)/h)in two cooking zones of a university canteen kitchen were evaluated.The result showed that the reduction of ILCR of COF exposure is the most important to the performance of exhaust hood.The comprehensive performance of orifice exhaust hood with exhaust rate of 4000 and 5000 m^(3)/h are optimal;the orifice exhaust hood with exhaust of 3000 m^(3)/h and grille exhaust hood with exhaust rate of 5000 m^(3)/h are moderate;the grille exhaust hood with exhaust rate of 3000 and 4000 m^(3)/h are low.Decision-making priorities based on comprehensive and individual performance are not exactly the same in the two cooking zones.It is necessary to use the index system to evaluate the comprehensive performance of exhaust hood that considers the impact on human health and thermal comfort.展开更多
Betula platyphylla var. mandshurica Hara. is a geographical variant of B. platyphylla Suk. with strong adaptability, rapid growth, fine texture, wide application and other notable features. In order to investigate the...Betula platyphylla var. mandshurica Hara. is a geographical variant of B. platyphylla Suk. with strong adaptability, rapid growth, fine texture, wide application and other notable features. In order to investigate the genetic effects of quantitative traits and specificity of different populations of B. platyphylla var. mandshurica Hara. , by permanent sample plot continuous measurement and temporary sample plot random investigation, B. platyphyUa var. mandshurica Hara. populations naturally distributed in Zhangguangcailing Mountain and Laoye Mountain in Changbai Mountain Range were used as experimental materials to systemati- cally analyze the growth dynamic patterns of plant height and diameter at breast height, and comprehensively evaluate the genetic effects of various quantitative traits. According to the results, site conditions suitable for B. platyphylla var. mandshurica Hara. were classified into four grades according to the absolute value of partial correlation coefficients. The growth process of B. platyphylla var. mandshurica Hara. stand generally underwent rapid growth period, steady growth period and slow growth period. The growth of B. platyphylla var. mandshurica Hara. stand at different growth stages varied signitlcantly among various site grades, but the growth trend was basieally the same. Plant height, diameter at breast height, east-west crown diameter and north-south crown diameter varied significantly among B. platyphylla vat. mandshurica Hara. populations, exhibiting extremely significant differences. The heritability of four growth traits was 0. 558,0. 762, 0. 652 and 0. 722, respectively; the genetic gain was 8.09%, 17.67%, 14.56% and 17.53%, respectively. Based on comprehensive evaluation of various indicators, MES （Maoershan） was identified as an excellent population, which exhibited minor variations between individuals within the population, stable growth, strong growth potential and remarkable genetie effects.展开更多
基金Fund by the National Natural Science Foundation of China (No.51778101)the General Program (Key Program,Major Research Plan)of National Natural Science Foundation of China+2 种基金the National Key R&D Program (No.2020YFC1909304)the National Program on Key Basic Research Project of Chinathe Joint Fund Project of National Natural Fund of China (U1908227)。
文摘In order to better understand the thermodynamic properties of magnesium oxysulfate(MOS)cement,pure reagent was analyzed to prepare magnesium sulfide cement,non-isothermal kinetics calculation of the main hydration products was also carried out,and the conversion process of magnesium sulfide cement 517 phase at different temperatures was investigated.Composition of magnesium sulfide cement prepared was measured by XRD technique,and decomposed by a comprehensive thermal analyzer,and DSC curves of magnesium sulfide cement under different temperature rising rates were processed by Kinssinger method and Dolye-Ozawa method.According to the TG-DSC curves of magnesium sulfide cement,the thermal decomposition reaction process can be divided into five stages under normal conditions.The DSC curve was processed by Kinssinger method and Dolye-Ozawa method,and the kinetic analysis was carried out to calculate the 517 phase activation energy of magnesium sulfide cement.The three stages correspond to different activation energies.Therefore,flame retardant mechanism and thermal decomposition mechanism of magnesium sulfide cement based materials are deduced.
基金U nder the auspices of the M ajor State B asic R esearch D evelopm ent Program of C hina (973 Program ) (N o.2005C B 724205)
文摘Ecological demonstration area (EDA) is an authorized nomination, which should be assessed from several aspects, including ecological, social, environmental, economic ones and so on. It is difficult to advance an exact developing level index of EDA due to its indicator system’s complexity and disequilibrium. In this paper, a framework of indicators was set to evaluate, monitor and examine the comprehensive level of ecological demonstration area (EDA). Fuzzy logic method was used to develop the fuzzy comprehensive evaluation model (FCEM), which could quantitatively reveal the developing degree of EDA. Huiji District of Zhengzhou, Henan Province, one of the 9th group of national EDAs, was taken as a study case. The framework of FCEM for the integrated system included six subsystems, which were social, economic, ecological, rural, urban and accessorial description ones. The research would be valuable in the comprehensive quantitative evaluation of EDA and would work as a guide in the construction practices of Huiji ecological demonstration area.
基金Strategic Priority Research Program of the CAS,Pan-Third Pole Environment Study for a Green Silk Road,No.XDA20040402。
文摘In the context of accelerated development of the Silk Road Economic Belt,it is necessary to conduct in-depth research on urbanization of Central Asian countries.This paper analyzes the spatial and temporal patterns and evolution dynamics of urbanization during the period 1991-2017 from the perspective of internal-external forces.The results are as follows.(1)The urbanization process of the five Central Asian countries studied is significantly influenced by their political and economic situations and displays periodic characteristics.All five countries experienced a stagnation development stage at the beginning of independence,and then a rapid growth stage since the year 2000.The average annual growth rates of the two stages were 0.19% and 1.45%,respectively.(2)Differences in the urbanization of the studied countries are obvious,and the evolutionary characteristics of each subsystem of urbanization are different.It is therefore necessary to distinguish and clearly understand the urbanization process of each country.(3)Internal and external factors play a role in the urbanization processes of Central Asian countries.External railway transportation facilities are particularly important for the development of urbanization in these countries.The regression coefficients of railway construction length,total merchandise trade and actually utilized foreign capital are 0.5665,0.0937 and 0.0806,respectively.(4)Countries with smaller populations and economic scales need to engage in international cooperation to promote healthy development of urbanization.The results of the study indicate that internal and external factors work together in the urbanization process of Central Asian countries,and external forces are particularly important for the development of such urbanization.
基金supported by the National Key R&D Program of China(No.2017YFC0211502).
文摘Indicators are the basis for judging the working performance of exhaust hood and capture performance are usually used as the only indicator.An evaluation index system including three factors of cooking oil fumes(COF)instantaneous capture,health risk impact and thermal comfort was proposed to assess the comprehensive performance of exhaust hood in the present study.The primary capture efficiency(PCE)of formaldehyde,the PCE of particulate matter with the diameter less than or equal to 2.5μm(PM_(2.5)),the incremental lifetime cancer risk(ILCR)of formaldehyde,the ILCR of PM_(2.5)and the predicted mean vote(PMV),which can all be quantified with the aid of computational fluid dynamics(CFD),were selected as the indicators.And the analytic hierarchy process(AHP)method was introduced to perform the comprehensive performance evaluation of exhaust hood.The performance of two exhaust hood structures(grille and orifice type)with three exhaust rates(3000,4000,and 5000 m^(3)/h)in two cooking zones of a university canteen kitchen were evaluated.The result showed that the reduction of ILCR of COF exposure is the most important to the performance of exhaust hood.The comprehensive performance of orifice exhaust hood with exhaust rate of 4000 and 5000 m^(3)/h are optimal;the orifice exhaust hood with exhaust of 3000 m^(3)/h and grille exhaust hood with exhaust rate of 5000 m^(3)/h are moderate;the grille exhaust hood with exhaust rate of 3000 and 4000 m^(3)/h are low.Decision-making priorities based on comprehensive and individual performance are not exactly the same in the two cooking zones.It is necessary to use the index system to evaluate the comprehensive performance of exhaust hood that considers the impact on human health and thermal comfort.
基金Supported by National Forestry Public Welfare Industry Research of China(201204307-07)Project for National Forest Tree Germplasm Platform Running Service of China(2011DKA21003-02)Science and Technology Support Program of Heilongjiang Province(GB07B301)
文摘Betula platyphylla var. mandshurica Hara. is a geographical variant of B. platyphylla Suk. with strong adaptability, rapid growth, fine texture, wide application and other notable features. In order to investigate the genetic effects of quantitative traits and specificity of different populations of B. platyphylla var. mandshurica Hara. , by permanent sample plot continuous measurement and temporary sample plot random investigation, B. platyphyUa var. mandshurica Hara. populations naturally distributed in Zhangguangcailing Mountain and Laoye Mountain in Changbai Mountain Range were used as experimental materials to systemati- cally analyze the growth dynamic patterns of plant height and diameter at breast height, and comprehensively evaluate the genetic effects of various quantitative traits. According to the results, site conditions suitable for B. platyphylla var. mandshurica Hara. were classified into four grades according to the absolute value of partial correlation coefficients. The growth process of B. platyphylla var. mandshurica Hara. stand generally underwent rapid growth period, steady growth period and slow growth period. The growth of B. platyphylla var. mandshurica Hara. stand at different growth stages varied signitlcantly among various site grades, but the growth trend was basieally the same. Plant height, diameter at breast height, east-west crown diameter and north-south crown diameter varied significantly among B. platyphylla vat. mandshurica Hara. populations, exhibiting extremely significant differences. The heritability of four growth traits was 0. 558,0. 762, 0. 652 and 0. 722, respectively; the genetic gain was 8.09%, 17.67%, 14.56% and 17.53%, respectively. Based on comprehensive evaluation of various indicators, MES （Maoershan） was identified as an excellent population, which exhibited minor variations between individuals within the population, stable growth, strong growth potential and remarkable genetie effects.
