In the production and life of ancient Chinese folk artists,through the abstract and geometric arrangement of things,they formed many meaningful patterns.These patterns are widely used in a variety of decorations,refle...In the production and life of ancient Chinese folk artists,through the abstract and geometric arrangement of things,they formed many meaningful patterns.These patterns are widely used in a variety of decorations,reflecting the most simple artistic ideas in the life of the working people,and are also an important embodiment of folk art aesthetics.Many elements of folk patterns have been preserved to this day,and they have an important role in inspiring and guiding today’s art design.This paper mainly analyzes the folk pattern elements and their artistic value,and elaborates on the application of folk pattern elements in architectural design and the specific design methods,to provide certain references for the combination of modern architectural design and traditional folk patterns.展开更多
It has recently become evident that the de novo emergence of genes is widespread and documented for a variety of organisms.De novo genes frequently emerge in proximity to existing genes,forming gene overlaps.Here,we p...It has recently become evident that the de novo emergence of genes is widespread and documented for a variety of organisms.De novo genes frequently emerge in proximity to existing genes,forming gene overlaps.Here,we present an analysis of the evolutionary history of a putative de novo gene,lawc,which overlaps with the conserved Trf2 gene,which encodes a general transcription factor in Drosophila melanogaster.We demonstrate that lawc emerged approximately 68 million years ago in the 5'-untranslated region(UTR)of Trf2 and displays an extensive spatiotemporal expression pattern.One of the most remarkable features of the lawc evolutionary history is that its emergence was facilitated by the engagement of Drosophilidae-specific short,highly conserved regions located in Trf2 introns.This represents a unique example of putative de novo gene birth involving conserved DNA regions localized in introns of conserved genes.The observed lawc expression pattern may be due to the overlap of lawc with the 5'-UTR of Trf2.This study not only enriches our understanding of gene evolution but also highlights the complex interplay between genetic conservation and innovation.展开更多
As lithium-ion batteries(LIBs)continue to evolve toward lower costs and higher energy densities,their potential safety risks have become increasingly apparent.Incidents such as explosions at energy storage facilities,...As lithium-ion batteries(LIBs)continue to evolve toward lower costs and higher energy densities,their potential safety risks have become increasingly apparent.Incidents such as explosions at energy storage facilities,fires in electric vehicles,and building fires ignited by charging two-wheeled vehicles have been occurring with alarming frequency,often resulting in significant casualties and injuries.Conducting indepth investigations into thermal runaway(TR)incidents in LIBs can significantly reduce the risk of future occurrences.However,current investigations into LIB fire and explosion incidents face challenges due to the difficulty of conducting in-depth analyses and the lack of a robust theoretical framework to guide these investigations.To enhance the effectiveness of in-depth investigations into battery fire and explosion incidents and to address the lack of theoretical guidance,this paper is the first to systematically examine the conservation and flow patterns of elements during the TR process of LIBs.The analysis reveals that during TR,the gas products generated include approximately 1.5 g of H_(2),23.6 g of CO,88.4 g of CO_(2),8.9 g of C_(2)H_(4),7.3 g of CH_(4),3.7 g of C_(2)H_(6),and 82 g of electrolyte vapor.After TR,the solid compounds formed consist of approximately 2.5 g of LiF,29–92.2 g of elemental Ni/Co/Mn,11.4 g of Li_(2)CO_(3),200.6 g of graphite,1.4 g of NiO,29.6 g of MnO,30.1 g of CoO,67 g of elemental Cu,0.03 g of LiNiO_(2),and 4.3 g of LiAlO_(2).Importantly,the energy released from reactions forming solid compounds during TR surpasses that from gas-forming reactions.This investigation represents the first application of Hess’s law to verify the conservation of elements during the TR process of lithium-ion batteries.The proposed methodology is also applicable to other types of energy storage batteries,effectively advancing techniques for comprehensively investigating lithium battery fire and explosion incidents.展开更多
A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc(GTA)welding pool with different sulfur concentrations.It has been shown that,the weld penetrati...A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc(GTA)welding pool with different sulfur concentrations.It has been shown that,the weld penetration increases sharply with increasing sulfur content.When sulfur content increases beyond 80×10-6,the increase in sulfur content does not have an appreciable difference on the welding pool size and shape,and the depth/width remains constant.Sulfur changes the temperature dependence of surface tension coefficient from a negative value to a positive value and causes significant changes on flow patterns.The increase in soluble sulfur content and the decrease at free surface temperature can extend the region of positive surface tension coefficient.As sulfur content exceeds 125×10-6,the sign of surface tension coefficient is positive.Depending upon the sulfur concentrations,three,one or two vortexes that have different positions,strength and directions may be found in the welding pool.The contrary vortexes can efficiently transfer the thermal energy from the arc,creating a deep welding pool.An optimum range of sulfur content is 20-150×10-6.展开更多
The content and distribution pattern of rare earth elements(REEs)in surface sediments from the Eastern and Western Pacifi c Ocean,the Northern and Southern Atlantic Ocean,and the Southwestern Indian Ocean were explore...The content and distribution pattern of rare earth elements(REEs)in surface sediments from the Eastern and Western Pacifi c Ocean,the Northern and Southern Atlantic Ocean,and the Southwestern Indian Ocean were explored and the resources and geochemical characteristics of REEs in deep-ocean sediments from diff erent oceans were studied.The total REE abundances(ΣREE)in the diff erent oceans ranged as follows:Eastern Pacifi c,56.88–500.02μg/g;Western Pacifi c,290.68–439.94μg/g;Northern Atlantic,55.33–154.90μg/g;Southern Atlantic,40.83–69.30μg/g;and Southwestern Indian Ocean,20.24–64.76μg/g.Their corresponding LREE(La-Eu)/HREE(Gd-Lu)average values were 5.18,5.86,9.01,5.21,and 4.59,which indicated that the light REEs were all evidently enriched.δEu andδCe showed slight Eu-negative anomalies and signifi cant Ce-positive anomalies in all sediments.Although the contents of REEs in the sediments varied among the diff erent oceans,the distribution patterns of REEs were similar,and the correlation coeffi cient was greater than 0.9290.In the Eastern Pacifi c sediments,ΣREE showed a signifi cantly positive correlation with Co,Cu,Zn,Mn,Mo and a weak correlation with Fe.In the Western Pacifi c and Southern Atlantic sediments,ΣREE presented no obvious correlation and a weakly negative correlation with Co,Cu,Zn,Mn,Mo and Fe,respectively.ΣREE in the Southwestern Indian Ocean sediments positively correlated with Cu,Zn,Mn,Mo,Fe,and had a weakly negative correlation with Co.展开更多
Landform elements with varying morphologies and spatial arrangements are recognized as feature indicator of landform classification and play a critical role in geomorphological studies.Differential geometry method has...Landform elements with varying morphologies and spatial arrangements are recognized as feature indicator of landform classification and play a critical role in geomorphological studies.Differential geometry method has been extensively applied in prior landform element research,while its efficacy in differentiating similar morphological characteristics remains inadequate to date.To reduce reliance on geomorphometric variables and increase awareness of landform patterns,geomorphons method was generated in previous study corresponding to specific landform reclassification map based on lookup table.Besides,to address the problem of feature similarity,hierarchical classification was proposed and effectively utilized for terrain recognition through the analytical strategy of fuzzy gradient features.Thus,combining the advantages of these two aspects,a hierarchical framework was proposed in this study for landform element pattern recognition considering the morphology and hierarchy factors.First,the local triplet patterns derived from geomorphons were enhanced by setting the flatness threshold,and subsequently adopted for the primary landform element recognition.Then,as geomorphic units with the same morphology possess different spatial analytical scales,the unidentified landform elements under the principle of scale adaptation were determined by calculating the spatial correlation and entropy information.To ensure the effectiveness of this proposed method,the sampling points were randomly selected from NASADEM data and then validated against a real 3D terrain model.Quantitative results of landform element pattern recognition demonstrate that our approach can reach above 77%average accuracy.Additionally,it delineates local details more effectively than geomorphons in visual assessment,resulting in a 7%accuracy improvement in overall scale.展开更多
On the basis of the in situ data of DO2, pH, SiO2. PO4-P, NO3-N and NO2-N collected in the north of the East China Sea during 1987-1988, the following points are mainly expounded.1.The inorgonic nutrients are obviousl...On the basis of the in situ data of DO2, pH, SiO2. PO4-P, NO3-N and NO2-N collected in the north of the East China Sea during 1987-1988, the following points are mainly expounded.1.The inorgonic nutrients are obviously affected by continent runoff in the north of the East China Sea. Their distributions are characteristic of its distribution of terrigenous materials.2.There are three transport paths of nutrients from the shelf to the Kuroshio area. The first is mixing-diffusing-advec-tion and upwelling process, the process of biology and biochemistry belongs to the second, and the sinking process is the last one.3.The swing of the Kuroshio axis affectes both the range of the migration of substances through mixing-diffusing-advec-tion process and the upwelling degree of the subsurface Kuroshio water to the shelf.4.Most part of the substances sink as macroparticles to the deep layer before reaching the Kuroshio area.展开更多
Concentrations of sixteen rare earth elements（REEs） in PM2.5 and potential-source samples, collected in Nanchang city in mid-September 2013, were determined by inductively coupled plasma mass spectrometry（ICP-MS）....Concentrations of sixteen rare earth elements（REEs） in PM2.5 and potential-source samples, collected in Nanchang city in mid-September 2013, were determined by inductively coupled plasma mass spectrometry（ICP-MS）. The results showed that the concentrations of total REEs（ΣREE） ranged from 78.76 to 1351 ng/mg. The order of REEs in PM2.5 samples showed the anthropogenic effects, Ce and Eu were affected more than the other REEs according to the enrichment factors. The results of chondrite-normalized REEs patterns and characteristic parameters showed evident light REEs fractionation, and positive anomalies of Ce and Eu in PM2.5. The other non-local pollution sources affected the PM2.5 samples, according to the triangular diagram of La, Ce and Sm compositions and plot of ΣREE vs δEu. Moreover, plot of（La/Sm）N vs（Gd/Yb）N revealed the effects of local sources. In conclusion, the REEs in potential-source samples were close to the background of local soil, while the REEs in PM2.5 samples in Nanchang city were jointly affected by the investigated local sources and other non-local sources.展开更多
To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for c...To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for content, and analyzed. Coal in northwestern China is characterized by low to extremely low levels of sulfur; the coal of the Taiyuan Formation in northern China mainly has high-sulfur content; that of the Shanxi Formation is mainly characterized by low sulfur coal; and the Late Permian coal in southern China has overall higher sulfur content; other regions have low sulfur coal. The average content of harmful trace elements in the bulk of China＇s coal is similar to the corresponding content in the coal of the North America and the rest of the world, whereas the content of various elements （Hg, Sb and Se） is different in magnitude to the corresponding percentage in the crust. The average content of the elements Cr, Se, Co, Be, U, Br in Late Permian coal in S China ranks first in the country whereas the average content of Hg and CI in the coals of Late Carboniferous to Early Permian age in N China are the highest. The average content of Mn in Early and Middle Jurassic coal is higher in NW China. The high content of harmful elements in some coal should cause particular concern both in the development and utilization of coal.展开更多
Active fault creep slip induces deformation of rock mass buried deeply in fault zones that significantly affect the operational safety of long linear projects passing through it.Displacement distribution patterns of r...Active fault creep slip induces deformation of rock mass buried deeply in fault zones that significantly affect the operational safety of long linear projects passing through it.Displacement distribution patterns of rock masses in active fault zones which have been investigated previously are the key design basis for such projects.Therefore,a discrete element numerical model with different fault types,slip time,dip angles,and complex geological features was established,and then the creep slip for normal,reverse,and strike-slip faults were simulated to analyze the displacement distribution in the fault rock mass.A disk rotation test system and the corresponding laboratory test method were developed for simulating rock mass displacement induced by creep slippage of faults.A series of rotation tests for softand hard-layered specimens under combined compression and torsional stress were conducted to verify the numerical results and analyze the factors influencing the displacement distribution.An S-shaped displacement distribution independent of fault dip angle was identified corresponding to reverse,normal,and strike-slip faults.The results indicated that the higher the degree of horizontal extrusion,the softer the rock mass at the fault core,and the higher the degree of displacement concentration in the fault core;about 70%of the creep slip displacement occurs within this zone under 100 years of creep slippage.展开更多
In our previous work, it was found that large electrospun from chlorinated polypropylene solution doped Bird＇s Nest patterned nanofibrous membranes can be simply with an ionic liquid, and a plausible formation mechan...In our previous work, it was found that large electrospun from chlorinated polypropylene solution doped Bird＇s Nest patterned nanofibrous membranes can be simply with an ionic liquid, and a plausible formation mechanism of Bird＇s Nest patterned architectures was proposed. Here, we use Ansoft Maxwell version 12 software （3D, electrostatic solver） to simulate the electrical field distribution of the electrospinning setup, and to clarify the rationality of proposed formation mechanism. Calculation results clearly show that the introduction of charged nanofibrous bundles would produce a similar patterned electrical field distribution, which definitely confirms the important role of surface residual charges. The proposed mechanism can be well extended to other polymer systems including polystyrene, poly（acrylonitrile-co-acrylic acid） and chitosan/poly（ethylene oxide）.展开更多
By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional or...By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional ore zonality has been discovered. During the early and late Yanshanian epoch （corresponding respectively to the Jurassic and Cretaceous periods）, two centers of ore formation emerged successively in the Nanling region; the former is mainly for rare metals （W, Sn, Mo, Bi, Nb） and one rare-earth element （La） and was generated in the Jurassic period; whereas the latter is mainly for base metals （Cu, Pb, Zn, Sb, Hg）, noble metals （Au, Ag）, and one radioactive element （U） and was generated in the Cretaceous period. Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan Province. The characteristic giant nonlinear target-pattern regional ore zonality was generated by spatio-temporal synchronization process of the Nanling complex metallogenic system. It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality. Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures. Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution. A new methodology for revealing regional ore zonality is developed, which will encourage further investigation of the formation of deep-seated ore resources and the onset of large-scale mineralization.展开更多
文摘In the production and life of ancient Chinese folk artists,through the abstract and geometric arrangement of things,they formed many meaningful patterns.These patterns are widely used in a variety of decorations,reflecting the most simple artistic ideas in the life of the working people,and are also an important embodiment of folk art aesthetics.Many elements of folk patterns have been preserved to this day,and they have an important role in inspiring and guiding today’s art design.This paper mainly analyzes the folk pattern elements and their artistic value,and elaborates on the application of folk pattern elements in architectural design and the specific design methods,to provide certain references for the combination of modern architectural design and traditional folk patterns.
基金funded by a grant from the Russian Science Foundation № 24-24-00354
文摘It has recently become evident that the de novo emergence of genes is widespread and documented for a variety of organisms.De novo genes frequently emerge in proximity to existing genes,forming gene overlaps.Here,we present an analysis of the evolutionary history of a putative de novo gene,lawc,which overlaps with the conserved Trf2 gene,which encodes a general transcription factor in Drosophila melanogaster.We demonstrate that lawc emerged approximately 68 million years ago in the 5'-untranslated region(UTR)of Trf2 and displays an extensive spatiotemporal expression pattern.One of the most remarkable features of the lawc evolutionary history is that its emergence was facilitated by the engagement of Drosophilidae-specific short,highly conserved regions located in Trf2 introns.This represents a unique example of putative de novo gene birth involving conserved DNA regions localized in introns of conserved genes.The observed lawc expression pattern may be due to the overlap of lawc with the 5'-UTR of Trf2.This study not only enriches our understanding of gene evolution but also highlights the complex interplay between genetic conservation and innovation.
基金supported by the National Natural Science Foundation of China(52106284,52422609)the Natural Science Foundation of Hebei Province(B2021507001)Key Research Special Project of CPPU(ZDZX202501)。
文摘As lithium-ion batteries(LIBs)continue to evolve toward lower costs and higher energy densities,their potential safety risks have become increasingly apparent.Incidents such as explosions at energy storage facilities,fires in electric vehicles,and building fires ignited by charging two-wheeled vehicles have been occurring with alarming frequency,often resulting in significant casualties and injuries.Conducting indepth investigations into thermal runaway(TR)incidents in LIBs can significantly reduce the risk of future occurrences.However,current investigations into LIB fire and explosion incidents face challenges due to the difficulty of conducting in-depth analyses and the lack of a robust theoretical framework to guide these investigations.To enhance the effectiveness of in-depth investigations into battery fire and explosion incidents and to address the lack of theoretical guidance,this paper is the first to systematically examine the conservation and flow patterns of elements during the TR process of LIBs.The analysis reveals that during TR,the gas products generated include approximately 1.5 g of H_(2),23.6 g of CO,88.4 g of CO_(2),8.9 g of C_(2)H_(4),7.3 g of CH_(4),3.7 g of C_(2)H_(6),and 82 g of electrolyte vapor.After TR,the solid compounds formed consist of approximately 2.5 g of LiF,29–92.2 g of elemental Ni/Co/Mn,11.4 g of Li_(2)CO_(3),200.6 g of graphite,1.4 g of NiO,29.6 g of MnO,30.1 g of CoO,67 g of elemental Cu,0.03 g of LiNiO_(2),and 4.3 g of LiAlO_(2).Importantly,the energy released from reactions forming solid compounds during TR surpasses that from gas-forming reactions.This investigation represents the first application of Hess’s law to verify the conservation of elements during the TR process of lithium-ion batteries.The proposed methodology is also applicable to other types of energy storage batteries,effectively advancing techniques for comprehensively investigating lithium battery fire and explosion incidents.
基金The authors would like to acknowledge the financial sup-port from the 973 State Key Fundamental Research Project:Fundamental Research of New Generation Iron and Steel Ma-terials(No.G1998061500).
文摘A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc(GTA)welding pool with different sulfur concentrations.It has been shown that,the weld penetration increases sharply with increasing sulfur content.When sulfur content increases beyond 80×10-6,the increase in sulfur content does not have an appreciable difference on the welding pool size and shape,and the depth/width remains constant.Sulfur changes the temperature dependence of surface tension coefficient from a negative value to a positive value and causes significant changes on flow patterns.The increase in soluble sulfur content and the decrease at free surface temperature can extend the region of positive surface tension coefficient.As sulfur content exceeds 125×10-6,the sign of surface tension coefficient is positive.Depending upon the sulfur concentrations,three,one or two vortexes that have different positions,strength and directions may be found in the welding pool.The contrary vortexes can efficiently transfer the thermal energy from the arc,creating a deep welding pool.An optimum range of sulfur content is 20-150×10-6.
基金Supported by the Basic Scientifi c Fund for National Public Research Institutes of China(No.2020Q10)and the China Ocean Mineral Resources R&D Association(Nos.DY135-E2-1-07,DY135-E2-4)。
文摘The content and distribution pattern of rare earth elements(REEs)in surface sediments from the Eastern and Western Pacifi c Ocean,the Northern and Southern Atlantic Ocean,and the Southwestern Indian Ocean were explored and the resources and geochemical characteristics of REEs in deep-ocean sediments from diff erent oceans were studied.The total REE abundances(ΣREE)in the diff erent oceans ranged as follows:Eastern Pacifi c,56.88–500.02μg/g;Western Pacifi c,290.68–439.94μg/g;Northern Atlantic,55.33–154.90μg/g;Southern Atlantic,40.83–69.30μg/g;and Southwestern Indian Ocean,20.24–64.76μg/g.Their corresponding LREE(La-Eu)/HREE(Gd-Lu)average values were 5.18,5.86,9.01,5.21,and 4.59,which indicated that the light REEs were all evidently enriched.δEu andδCe showed slight Eu-negative anomalies and signifi cant Ce-positive anomalies in all sediments.Although the contents of REEs in the sediments varied among the diff erent oceans,the distribution patterns of REEs were similar,and the correlation coeffi cient was greater than 0.9290.In the Eastern Pacifi c sediments,ΣREE showed a signifi cantly positive correlation with Co,Cu,Zn,Mn,Mo and a weak correlation with Fe.In the Western Pacifi c and Southern Atlantic sediments,ΣREE presented no obvious correlation and a weakly negative correlation with Co,Cu,Zn,Mn,Mo and Fe,respectively.ΣREE in the Southwestern Indian Ocean sediments positively correlated with Cu,Zn,Mn,Mo,Fe,and had a weakly negative correlation with Co.
基金supported by the National Natural Science Foundation of China(Grant Nos.41930102,41971339 and 41771423)Shandong University of Science and Technology Research Fund(No.2019TDJH103)。
文摘Landform elements with varying morphologies and spatial arrangements are recognized as feature indicator of landform classification and play a critical role in geomorphological studies.Differential geometry method has been extensively applied in prior landform element research,while its efficacy in differentiating similar morphological characteristics remains inadequate to date.To reduce reliance on geomorphometric variables and increase awareness of landform patterns,geomorphons method was generated in previous study corresponding to specific landform reclassification map based on lookup table.Besides,to address the problem of feature similarity,hierarchical classification was proposed and effectively utilized for terrain recognition through the analytical strategy of fuzzy gradient features.Thus,combining the advantages of these two aspects,a hierarchical framework was proposed in this study for landform element pattern recognition considering the morphology and hierarchy factors.First,the local triplet patterns derived from geomorphons were enhanced by setting the flatness threshold,and subsequently adopted for the primary landform element recognition.Then,as geomorphic units with the same morphology possess different spatial analytical scales,the unidentified landform elements under the principle of scale adaptation were determined by calculating the spatial correlation and entropy information.To ensure the effectiveness of this proposed method,the sampling points were randomly selected from NASADEM data and then validated against a real 3D terrain model.Quantitative results of landform element pattern recognition demonstrate that our approach can reach above 77%average accuracy.Additionally,it delineates local details more effectively than geomorphons in visual assessment,resulting in a 7%accuracy improvement in overall scale.
文摘On the basis of the in situ data of DO2, pH, SiO2. PO4-P, NO3-N and NO2-N collected in the north of the East China Sea during 1987-1988, the following points are mainly expounded.1.The inorgonic nutrients are obviously affected by continent runoff in the north of the East China Sea. Their distributions are characteristic of its distribution of terrigenous materials.2.There are three transport paths of nutrients from the shelf to the Kuroshio area. The first is mixing-diffusing-advec-tion and upwelling process, the process of biology and biochemistry belongs to the second, and the sinking process is the last one.3.The swing of the Kuroshio axis affectes both the range of the migration of substances through mixing-diffusing-advec-tion process and the upwelling degree of the subsurface Kuroshio water to the shelf.4.Most part of the substances sink as macroparticles to the deep layer before reaching the Kuroshio area.
基金Project supported by the National Natural Science Foundation of China(21477042,21377042)the Natural Science Foundation of Fujian Province(2016J01065)
文摘Concentrations of sixteen rare earth elements（REEs） in PM2.5 and potential-source samples, collected in Nanchang city in mid-September 2013, were determined by inductively coupled plasma mass spectrometry（ICP-MS）. The results showed that the concentrations of total REEs（ΣREE） ranged from 78.76 to 1351 ng/mg. The order of REEs in PM2.5 samples showed the anthropogenic effects, Ce and Eu were affected more than the other REEs according to the enrichment factors. The results of chondrite-normalized REEs patterns and characteristic parameters showed evident light REEs fractionation, and positive anomalies of Ce and Eu in PM2.5. The other non-local pollution sources affected the PM2.5 samples, according to the triangular diagram of La, Ce and Sm compositions and plot of ΣREE vs δEu. Moreover, plot of（La/Sm）N vs（Gd/Yb）N revealed the effects of local sources. In conclusion, the REEs in potential-source samples were close to the background of local soil, while the REEs in PM2.5 samples in Nanchang city were jointly affected by the investigated local sources and other non-local sources.
文摘To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for content, and analyzed. Coal in northwestern China is characterized by low to extremely low levels of sulfur; the coal of the Taiyuan Formation in northern China mainly has high-sulfur content; that of the Shanxi Formation is mainly characterized by low sulfur coal; and the Late Permian coal in southern China has overall higher sulfur content; other regions have low sulfur coal. The average content of harmful trace elements in the bulk of China＇s coal is similar to the corresponding content in the coal of the North America and the rest of the world, whereas the content of various elements （Hg, Sb and Se） is different in magnitude to the corresponding percentage in the crust. The average content of the elements Cr, Se, Co, Be, U, Br in Late Permian coal in S China ranks first in the country whereas the average content of Hg and CI in the coals of Late Carboniferous to Early Permian age in N China are the highest. The average content of Mn in Early and Middle Jurassic coal is higher in NW China. The high content of harmful elements in some coal should cause particular concern both in the development and utilization of coal.
基金Project(U1865203)supported by the Key Projects of the Yalong River Joint Fund of the National Natural Science Foundation of ChinaProjects(41941018,51879135)supported by the National Natural Science Foundation of China。
文摘Active fault creep slip induces deformation of rock mass buried deeply in fault zones that significantly affect the operational safety of long linear projects passing through it.Displacement distribution patterns of rock masses in active fault zones which have been investigated previously are the key design basis for such projects.Therefore,a discrete element numerical model with different fault types,slip time,dip angles,and complex geological features was established,and then the creep slip for normal,reverse,and strike-slip faults were simulated to analyze the displacement distribution in the fault rock mass.A disk rotation test system and the corresponding laboratory test method were developed for simulating rock mass displacement induced by creep slippage of faults.A series of rotation tests for softand hard-layered specimens under combined compression and torsional stress were conducted to verify the numerical results and analyze the factors influencing the displacement distribution.An S-shaped displacement distribution independent of fault dip angle was identified corresponding to reverse,normal,and strike-slip faults.The results indicated that the higher the degree of horizontal extrusion,the softer the rock mass at the fault core,and the higher the degree of displacement concentration in the fault core;about 70%of the creep slip displacement occurs within this zone under 100 years of creep slippage.
基金financially supported by the National Natural Science Foundation of China (No.50933006)Zhejiang Provincial Innovative Research Team (No.2009R50004)
文摘In our previous work, it was found that large electrospun from chlorinated polypropylene solution doped Bird＇s Nest patterned nanofibrous membranes can be simply with an ionic liquid, and a plausible formation mechanism of Bird＇s Nest patterned architectures was proposed. Here, we use Ansoft Maxwell version 12 software （3D, electrostatic solver） to simulate the electrical field distribution of the electrospinning setup, and to clarify the rationality of proposed formation mechanism. Calculation results clearly show that the introduction of charged nanofibrous bundles would produce a similar patterned electrical field distribution, which definitely confirms the important role of surface residual charges. The proposed mechanism can be well extended to other polymer systems including polystyrene, poly（acrylonitrile-co-acrylic acid） and chitosan/poly（ethylene oxide）.
基金supported by China Geological Survey Grants No. 1212010561603(2005)
文摘By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional ore zonality has been discovered. During the early and late Yanshanian epoch （corresponding respectively to the Jurassic and Cretaceous periods）, two centers of ore formation emerged successively in the Nanling region; the former is mainly for rare metals （W, Sn, Mo, Bi, Nb） and one rare-earth element （La） and was generated in the Jurassic period; whereas the latter is mainly for base metals （Cu, Pb, Zn, Sb, Hg）, noble metals （Au, Ag）, and one radioactive element （U） and was generated in the Cretaceous period. Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan Province. The characteristic giant nonlinear target-pattern regional ore zonality was generated by spatio-temporal synchronization process of the Nanling complex metallogenic system. It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality. Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures. Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution. A new methodology for revealing regional ore zonality is developed, which will encourage further investigation of the formation of deep-seated ore resources and the onset of large-scale mineralization.
