Coal and coal-shale undergo low-temperature oxidation when exposed to air,potentially leading to spontaneous combustion.Coal-shale found in association with coal seams vary considerably in their intrinsic properties a...Coal and coal-shale undergo low-temperature oxidation when exposed to air,potentially leading to spontaneous combustion.Coal-shale found in association with coal seams vary considerably in their intrinsic properties and spontaneous combustion liability index.Fourteen coal-shale samples collected from four different coal mines in Witbank Coalfield,South Africa,were experimentally investigated.The influence of coal-shale intrinsic properties and spontaneous combustion liability indices(determined by the WitsEhac Index and the Wits-CT Index)were established.The liability indices indicate relationships with the intrinsic factors and thus,identifying the major intrinsic factors affecting liability toward spontaneous combustion in these coal-shale samples.The XRF analysis indicated that the coal-shale samples are rich in Si O2,Al2O3 and Fe2O3,while the XRD showed that same coal-shale samples are generally dominated with kaolinite and quartz.The coal-shale occurred in association with medium Rank C bituminous coal and contained varying proportion of macerals.The Wits-Ehac Index was unable to reliably determine liability indices of some coal-shale samples,and hence the Wits-CT Index was developed.The results obtained from the characterisation tests may be used as a tool to predict the spontaneous combustion liability in carbonaceous material and may serve as a reference when comparing coal-shale from different coal mines.展开更多
In order to objectively and reasonably evaluate the actual and potential value of cultivated land, both social and ecological values are introduced into the classification and grading index system of cultivated land b...In order to objectively and reasonably evaluate the actual and potential value of cultivated land, both social and ecological values are introduced into the classification and grading index system of cultivated land based on the viewpoint of sustainable development, after considering the natural and economic values of cultivated land. Index system construction of the sustainable utilization of cultivated land should follow the principles of economic viability, social acceptability, and ecological protection. Classification of cultivated land should take into account the soil fertility of cultivated land. Then, grading of cultivated land is carried out from the practical productivity (or potential productivity) of cultivated land. According to the existing classification index system of cultivated land, the soil, natural and environmental factors in plains, mountains and hills are mainly modified in the classification index system of cultivated land. And index systems for the cultivated land classification in plains, mountains and hills are set up. The grading index system of cultivated land is established based on the economic viability (economic value), social acceptability (social value) and protection of cultivated land (ecological value). Quantitative expression of cultivated land grading index is also carried out.展开更多
Following slack-based inefficiency measurement method and Luenberger productivity index, this paper decomposes industrial environmental TFP index by input factors and output to estimate the sources of China＇s industr...Following slack-based inefficiency measurement method and Luenberger productivity index, this paper decomposes industrial environmental TFP index by input factors and output to estimate the sources of China＇s industrial environmental TFP. Results indicate that （1） China＇s industrial environmental TFP increased between 2001 and 2007 but declined in 2008 under the effect of global financial crisis; （2） input utilization productivity contributes 1/3 to industrial environmental TFP and pollution treatment productivity contributes about 2/3, which means that pollution treatment will effectively increase industrial environmental TFP; （3） capital utilization productivity contributes I/6 to input productivity and labor utilization productivity contributes about 5/6, which means that progress of labor production technologies is an effective means to increase industrial environmental TFP; （4） COD treatment productivity contributes roughly 2/3 to pollution treatment productivity, and S02 treatment productivity contributes about 1/3, which shows that priority on COD treatment will more effectively increase industrial environmental TFP.展开更多
We study the existence of multiple nonnegative solutions of the equation with y(0) = y(1) = y'(0) = y'(1) = 0. We show the existence of at least two non- negative solutions under f satisfying certain condition...We study the existence of multiple nonnegative solutions of the equation with y(0) = y(1) = y'(0) = y'(1) = 0. We show the existence of at least two non- negative solutions under f satisfying certain conditions by means of the fixed point index.展开更多
Let A be a ring.In this paper we generalize some results introduced by Aliabad and Mohamadian.We give a relation bet ween the z-ideals of A and t hose of the formal power series rings in an infinite set of indetermiii...Let A be a ring.In this paper we generalize some results introduced by Aliabad and Mohamadian.We give a relation bet ween the z-ideals of A and t hose of the formal power series rings in an infinite set of indetermiiiates over A.Consider A[[Xa]]3 and its subrings A[[X_(A)]]_(1),A[[X_(A)]]_(2),and A[[X_(A)]]_(α),where a is an infinite cardinal number.In fact,a z-ideal of the rings defined above is of the form I+(X_(A))i,where i=1,2,3 or an infinite cardinal number and I is a z-ideal of A.In addition,we prove that the same condition given by Aliabad and Mohamadian can be used to get a relation between the minimal prime ideals of the ring of the formal power series in an infinite set of indeterminates and those of the ring of coefficients.As a natural result,we get a relation between the z°-ideals of the formal power series ring in an infinite set of indeterminates and those of the ring of coefficients.展开更多
基金funded by Coaltech and is part of a PhD research/Postdoctoral study in the School of Mining Engineering at the University of the Witwatersrand
文摘Coal and coal-shale undergo low-temperature oxidation when exposed to air,potentially leading to spontaneous combustion.Coal-shale found in association with coal seams vary considerably in their intrinsic properties and spontaneous combustion liability index.Fourteen coal-shale samples collected from four different coal mines in Witbank Coalfield,South Africa,were experimentally investigated.The influence of coal-shale intrinsic properties and spontaneous combustion liability indices(determined by the WitsEhac Index and the Wits-CT Index)were established.The liability indices indicate relationships with the intrinsic factors and thus,identifying the major intrinsic factors affecting liability toward spontaneous combustion in these coal-shale samples.The XRF analysis indicated that the coal-shale samples are rich in Si O2,Al2O3 and Fe2O3,while the XRD showed that same coal-shale samples are generally dominated with kaolinite and quartz.The coal-shale occurred in association with medium Rank C bituminous coal and contained varying proportion of macerals.The Wits-Ehac Index was unable to reliably determine liability indices of some coal-shale samples,and hence the Wits-CT Index was developed.The results obtained from the characterisation tests may be used as a tool to predict the spontaneous combustion liability in carbonaceous material and may serve as a reference when comparing coal-shale from different coal mines.
基金Supported by the Key Project of Chinese Ministry of Education ( 108098)the National Natural Science Foundation of China ( 40671078,40771088)the Dangui Plan of Huazhong Normal University
文摘In order to objectively and reasonably evaluate the actual and potential value of cultivated land, both social and ecological values are introduced into the classification and grading index system of cultivated land based on the viewpoint of sustainable development, after considering the natural and economic values of cultivated land. Index system construction of the sustainable utilization of cultivated land should follow the principles of economic viability, social acceptability, and ecological protection. Classification of cultivated land should take into account the soil fertility of cultivated land. Then, grading of cultivated land is carried out from the practical productivity (or potential productivity) of cultivated land. According to the existing classification index system of cultivated land, the soil, natural and environmental factors in plains, mountains and hills are mainly modified in the classification index system of cultivated land. And index systems for the cultivated land classification in plains, mountains and hills are set up. The grading index system of cultivated land is established based on the economic viability (economic value), social acceptability (social value) and protection of cultivated land (ecological value). Quantitative expression of cultivated land grading index is also carried out.
文摘Following slack-based inefficiency measurement method and Luenberger productivity index, this paper decomposes industrial environmental TFP index by input factors and output to estimate the sources of China＇s industrial environmental TFP. Results indicate that （1） China＇s industrial environmental TFP increased between 2001 and 2007 but declined in 2008 under the effect of global financial crisis; （2） input utilization productivity contributes 1/3 to industrial environmental TFP and pollution treatment productivity contributes about 2/3, which means that pollution treatment will effectively increase industrial environmental TFP; （3） capital utilization productivity contributes I/6 to input productivity and labor utilization productivity contributes about 5/6, which means that progress of labor production technologies is an effective means to increase industrial environmental TFP; （4） COD treatment productivity contributes roughly 2/3 to pollution treatment productivity, and S02 treatment productivity contributes about 1/3, which shows that priority on COD treatment will more effectively increase industrial environmental TFP.
文摘We study the existence of multiple nonnegative solutions of the equation with y(0) = y(1) = y'(0) = y'(1) = 0. We show the existence of at least two non- negative solutions under f satisfying certain conditions by means of the fixed point index.
文摘Let A be a ring.In this paper we generalize some results introduced by Aliabad and Mohamadian.We give a relation bet ween the z-ideals of A and t hose of the formal power series rings in an infinite set of indetermiiiates over A.Consider A[[Xa]]3 and its subrings A[[X_(A)]]_(1),A[[X_(A)]]_(2),and A[[X_(A)]]_(α),where a is an infinite cardinal number.In fact,a z-ideal of the rings defined above is of the form I+(X_(A))i,where i=1,2,3 or an infinite cardinal number and I is a z-ideal of A.In addition,we prove that the same condition given by Aliabad and Mohamadian can be used to get a relation between the minimal prime ideals of the ring of the formal power series in an infinite set of indeterminates and those of the ring of coefficients.As a natural result,we get a relation between the z°-ideals of the formal power series ring in an infinite set of indeterminates and those of the ring of coefficients.
