December 12, 2014-China Academy of Telecommunication Research of MIIT has announced its analysis report of domestic mobile phone market of November 2014. In November 2014, the overall shipments of mobile phones reach...December 12, 2014-China Academy of Telecommunication Research of MIIT has announced its analysis report of domestic mobile phone market of November 2014. In November 2014, the overall shipments of mobile phones reached 44.543 million units in China. Among which 2G mobile phone shipments was of 5.742 million, 3G mobile phone was of 7.2 million and 31.601 million for 4G ones. 4G mobile phone shipments continued to increase rapidly, which was more than 4 times of 3G mobile phone shipments.展开更多
The in-orbit commissioning of ZY-1 02C satellite is proceeding smoothly. According to the relevant experts in this field, the imagery quality of the satellite has reached or nearly reached the level of international s...The in-orbit commissioning of ZY-1 02C satellite is proceeding smoothly. According to the relevant experts in this field, the imagery quality of the satellite has reached or nearly reached the level of international satellites of the same kind. ZY-1 02C satellite and ZY-3 satellite were successfully launched on December 22, 2011 and January 9, 2012 respectively. China Centre for Resources Satellite Data andApplication (CRSDA) was responsible for the building of a ground展开更多
On June 19,2020 the project“Development and application of package technology for manufacture of 5 kt/a of hydrogenation catalysts”,in the implementation of which the Resarch Institute of Petroleum Processing(RIPP)h...On June 19,2020 the project“Development and application of package technology for manufacture of 5 kt/a of hydrogenation catalysts”,in the implementation of which the Resarch Institute of Petroleum Processing(RIPP)has been taking part,had passed the apparaisal organized by the SINOPEC Science and Technology Division.This project has realized the integration,scale-up,and automation of hydrogenation catalyst production unit,while achieving low energy consumption and cleanness of hydrogenation catalyst production process,with its technology reaching an internationally advanced level.展开更多
The energy consumption of copper smelting in china reaches the lowest the world.According to information collected from China Nonferrous Metal Industry Association,in 2010,Dongying Fangyuan Non-ferrous Metals
[Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in t...[Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in the Upper Yangtze River.This study initiated continuous monitoring of natural spawning habitats from February 2022 to assess these ecological changes.[Methods]Environmental DNA(eDNA)metabarcoding was employed to analyze fish species composition,biodiversity patterns,and niche parameters of dominant species.Water sampling followed the CEN/TS 19461 standard across five monitoring transects(ZT1-ZT5).[Results]The eDNA analysis detected 45 species of fish belonging to 38 genera,13 families,and 3 orders were detected through environmental DNA(eDNA)in this survey,including 10 species endemic to the upper reaches of the Yangtze River,such as Procypris rabaudi and Myxocyprinus asiaticus.The fish community was mainly composed of bottom-dwelling,settling ovum-producing,omnivorous fish.The variation ranges of the Chao1 index,ACE index,Shannon index,and Simpson index are 736~996,719~965,1.58~3.23,and 0.83~0.99,respectively,indicating that fish species in spawning sites are abundant and community distribution uniformity is high.All indexes are highest at ZT1 monitoring points.Cluster analysis showed that,at a certain similarity level,fish community types in spawning sites could be basically divided into two groups:ZT1,ZT3,and ZT5 clustered together,and ZT2 and ZT4 clustered together,indicating similar fish community habitats.There are 9 dominant fish species in typical deep pool habitats in the reserve,with niche widths(Bi)ranging from 1.13 to 3.87.The dominant fish species are broad and medium niche fish,such as Cyprinus carpio and Hemiculter tchangi,with the niche overlap index(Oik)of some dominant fish species reaching more than 0.95.This indicates fierce competition for resources among the fish in this spawning ground.[Conclusion]The Zhutuo spawning ground demonstrates high species richness with homogeneous community structure and intense resource competition.This study establishes an eDNA-based monitoring framework that enhances conventional survey method,providing critical baseline data for adaptive management under the fishing moratorium regime.展开更多
The global issue of climate change presents young entrepreneurs with opportunities to explore new business models.FACED with the severe challenges presented by global climate change,pursuing a green lifestyle is a way...The global issue of climate change presents young entrepreneurs with opportunities to explore new business models.FACED with the severe challenges presented by global climate change,pursuing a green lifestyle is a way to achieve sustainable development.Many countries are exploring ways to reach a balance between economic development and environmental protection.展开更多
Collaborative changes in the hydro-sediment regime and erosional base level are vital factors that influence the evolution of wandering rivers.In the wandering Xiaobeiganliu reach of the Middle Yellow River(MYR),the r...Collaborative changes in the hydro-sediment regime and erosional base level are vital factors that influence the evolution of wandering rivers.In the wandering Xiaobeiganliu reach of the Middle Yellow River(MYR),the rapidly decreasing sediment discharge and lowering base level,i.e.,the Tongguan elevation,have resulted in new features of thalweg migration in river morphology.In this work,on the basis of topographic measurements of the reach from 2003–2021,the thalweg migration distance and intensity were calculated at both the section scale and reach scale.The results revealed that the annual sediment discharge decreased by 72%from 1986–2002,and the reach exhibited sustained scouring from deposition,leading to the Tongguan elevation decreasing by 1.69 m compared with that in 2002.Accordingly,the distance and intensity of thalweg migration have been reduced to varying degrees in both section and reach scales.The maximum section-scale thalweg migration distance was reduced by 11%,whereas the average thalweg migration distance and intensity at the reach scale decreased by 14%and 43%,respectively.During this sustained scouring period,the fluvial erosion intensity at the reach scale increased as the sediment discharge decreased.However,because the base level remained high,riverbed undercutting was deeply limited,which exacerbated lateral erosion of the bank and floodplain,enhancing thalweg migration.Flow-sediment regulation and training can be coupled to increase undercutting efficiency in the main channel and to protect banks from lateral erosion in river reach management.展开更多
随着欧盟《关于化学品注册、评估、授权和限制的法规》(Registration,Evaluation,Authorization and Restriction of Chemicals,REACH)管控要求越发严苛,作为直接接触人体皮肤产品的纺织品,需要对其高度关注物质(substances of very hig...随着欧盟《关于化学品注册、评估、授权和限制的法规》(Registration,Evaluation,Authorization and Restriction of Chemicals,REACH)管控要求越发严苛,作为直接接触人体皮肤产品的纺织品,需要对其高度关注物质(substances of very high concern,SVHC)残留情况进行检测,因此研究适用于纺织品基质复杂的SVHC筛查方法十分必要。针对纺织品基质复杂、SVHC种类多样以及传统的前处理方法耗时费力等问题,采用QuEChERS(quick、easy、cheap、eff ective、rugged、safe)前处理结合超高效液相色谱串联质谱(UPLC-MS/MS)的方法建立了一种纺织品SVHC快速筛查方法,通过优化前处理参数、色谱-质谱条件等手段对方法的线性范围、检出限(lower detection quantity,LOD)、定量限(lower quantification limit,LOQ)、回收率及精密度进行考查并应用于实际纺织品样品的筛查。研究表明,该方法具有简单快捷、灵敏度高、抗基质干扰能力强等特点,能适用于多种SVHC的纺织品筛查。展开更多
The backwater effect caused by tributary inflow can significantly elevate the water level profile upstream of a confluence point.However,the influence of mainstream and confluence discharges on the backwater effect in...The backwater effect caused by tributary inflow can significantly elevate the water level profile upstream of a confluence point.However,the influence of mainstream and confluence discharges on the backwater effect in a river reach remains unclear.In this study,various hydrological data collected from the Jingjiang Reach of the Yangtze River in China were statistically analyzed to determine the backwater degree and range with three representative mainstream discharges.The results indicated that the backwater degree increased with mainstream discharge,and a positive relationship was observed between the runoff ratio and backwater degree at specific representative mainstream discharges.Following the operation of the Three Gorges Project,the backwater effect in the Jingjiang Reach diminished.For instance,mean backwater degrees for low,moderate,and high mainstream discharges were recorded as 0.83 m,1.61 m,and 2.41 m during the period from 1990 to 2002,whereas these values decreased to 0.30 m,0.95 m,and 2.08 m from 2009 to 2020.The backwater range extended upstream as mainstream discharge increased from 7000 m3/s to 30000 m3/s.Moreover,a random forest-based machine learning model was used to quantify the backwater effect with varying mainstream and confluence discharges,accounting for the impacts of mainstream discharge,confluence discharge,and channel degradation in the Jingjiang Reach.At the Jianli Hydrological Station,a decrease in mainstream discharge during flood seasons resulted in a 7%–15%increase in monthly mean backwater degree,while an increase in mainstream discharge during dry seasons led to a 1%–15%decrease in monthly mean backwater degree.Furthermore,increasing confluence discharge from Dongting Lake during June to July and September to November resulted in an 11%–42%increase in monthly mean backwater degree.Continuous channel degradation in the Jingjiang Reach contributed to a 6%–19%decrease in monthly mean backwater degree.Under the influence of these factors,the monthly mean backwater degree in 2017 varied from a decrease of 53%to an increase of 37%compared to corresponding values in 1991.展开更多
With accelerated expansion,the Shanghai Cooperation Organization(SCO)has extended its geographical reach to the vast Eurasian region,where the balance of power has undergone profound changes since the end of the Cold ...With accelerated expansion,the Shanghai Cooperation Organization(SCO)has extended its geographical reach to the vast Eurasian region,where the balance of power has undergone profound changes since the end of the Cold War,showing instability and uncertainty.The type of order that can emerge in a region depends on the effectiveness of governance and the power structures and systems built upon it.The SCO advocates a brand new philosophy of cooperation that transcends the traditional mentality of international relations,forging a new model of multilateral collaboration.The SCO has vigorously participated in improving regional governance and is thus playing an increasingly important and unique role in reshaping the Eurasian regional order.展开更多
This paper introduces a novel chattering-free terminal sliding mode control(SMC)strategy to address chaotic behavior in permanent magnet synchronous generators(PMSG)for offshore wind turbine systems.By integrating an ...This paper introduces a novel chattering-free terminal sliding mode control(SMC)strategy to address chaotic behavior in permanent magnet synchronous generators(PMSG)for offshore wind turbine systems.By integrating an adaptive exponential reaching law with a continuous barrier function,the proposed approach eliminates chattering and ensures robust performance under model uncertainties.The methodology combines adaptive SMC with dynamic switching to estimate and compensates for unknown uncertainties,providing smooth and stable control.Finally,the performance and effectiveness of the proposed approach are compared with those of a previous study.展开更多
文摘December 12, 2014-China Academy of Telecommunication Research of MIIT has announced its analysis report of domestic mobile phone market of November 2014. In November 2014, the overall shipments of mobile phones reached 44.543 million units in China. Among which 2G mobile phone shipments was of 5.742 million, 3G mobile phone was of 7.2 million and 31.601 million for 4G ones. 4G mobile phone shipments continued to increase rapidly, which was more than 4 times of 3G mobile phone shipments.
文摘The in-orbit commissioning of ZY-1 02C satellite is proceeding smoothly. According to the relevant experts in this field, the imagery quality of the satellite has reached or nearly reached the level of international satellites of the same kind. ZY-1 02C satellite and ZY-3 satellite were successfully launched on December 22, 2011 and January 9, 2012 respectively. China Centre for Resources Satellite Data andApplication (CRSDA) was responsible for the building of a ground
文摘On June 19,2020 the project“Development and application of package technology for manufacture of 5 kt/a of hydrogenation catalysts”,in the implementation of which the Resarch Institute of Petroleum Processing(RIPP)has been taking part,had passed the apparaisal organized by the SINOPEC Science and Technology Division.This project has realized the integration,scale-up,and automation of hydrogenation catalyst production unit,while achieving low energy consumption and cleanness of hydrogenation catalyst production process,with its technology reaching an internationally advanced level.
文摘The energy consumption of copper smelting in china reaches the lowest the world.According to information collected from China Nonferrous Metal Industry Association,in 2010,Dongying Fangyuan Non-ferrous Metals
文摘[Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in the Upper Yangtze River.This study initiated continuous monitoring of natural spawning habitats from February 2022 to assess these ecological changes.[Methods]Environmental DNA(eDNA)metabarcoding was employed to analyze fish species composition,biodiversity patterns,and niche parameters of dominant species.Water sampling followed the CEN/TS 19461 standard across five monitoring transects(ZT1-ZT5).[Results]The eDNA analysis detected 45 species of fish belonging to 38 genera,13 families,and 3 orders were detected through environmental DNA(eDNA)in this survey,including 10 species endemic to the upper reaches of the Yangtze River,such as Procypris rabaudi and Myxocyprinus asiaticus.The fish community was mainly composed of bottom-dwelling,settling ovum-producing,omnivorous fish.The variation ranges of the Chao1 index,ACE index,Shannon index,and Simpson index are 736~996,719~965,1.58~3.23,and 0.83~0.99,respectively,indicating that fish species in spawning sites are abundant and community distribution uniformity is high.All indexes are highest at ZT1 monitoring points.Cluster analysis showed that,at a certain similarity level,fish community types in spawning sites could be basically divided into two groups:ZT1,ZT3,and ZT5 clustered together,and ZT2 and ZT4 clustered together,indicating similar fish community habitats.There are 9 dominant fish species in typical deep pool habitats in the reserve,with niche widths(Bi)ranging from 1.13 to 3.87.The dominant fish species are broad and medium niche fish,such as Cyprinus carpio and Hemiculter tchangi,with the niche overlap index(Oik)of some dominant fish species reaching more than 0.95.This indicates fierce competition for resources among the fish in this spawning ground.[Conclusion]The Zhutuo spawning ground demonstrates high species richness with homogeneous community structure and intense resource competition.This study establishes an eDNA-based monitoring framework that enhances conventional survey method,providing critical baseline data for adaptive management under the fishing moratorium regime.
文摘The global issue of climate change presents young entrepreneurs with opportunities to explore new business models.FACED with the severe challenges presented by global climate change,pursuing a green lifestyle is a way to achieve sustainable development.Many countries are exploring ways to reach a balance between economic development and environmental protection.
基金National Key R&D Program of China,No.2023YFC3206205National Natural Science Foundation of China,No.U22A20237Independent Research Project of Yellow River Engineering Consulting Co.,Ltd.,No.2025KY001。
文摘Collaborative changes in the hydro-sediment regime and erosional base level are vital factors that influence the evolution of wandering rivers.In the wandering Xiaobeiganliu reach of the Middle Yellow River(MYR),the rapidly decreasing sediment discharge and lowering base level,i.e.,the Tongguan elevation,have resulted in new features of thalweg migration in river morphology.In this work,on the basis of topographic measurements of the reach from 2003–2021,the thalweg migration distance and intensity were calculated at both the section scale and reach scale.The results revealed that the annual sediment discharge decreased by 72%from 1986–2002,and the reach exhibited sustained scouring from deposition,leading to the Tongguan elevation decreasing by 1.69 m compared with that in 2002.Accordingly,the distance and intensity of thalweg migration have been reduced to varying degrees in both section and reach scales.The maximum section-scale thalweg migration distance was reduced by 11%,whereas the average thalweg migration distance and intensity at the reach scale decreased by 14%and 43%,respectively.During this sustained scouring period,the fluvial erosion intensity at the reach scale increased as the sediment discharge decreased.However,because the base level remained high,riverbed undercutting was deeply limited,which exacerbated lateral erosion of the bank and floodplain,enhancing thalweg migration.Flow-sediment regulation and training can be coupled to increase undercutting efficiency in the main channel and to protect banks from lateral erosion in river reach management.
文摘随着欧盟《关于化学品注册、评估、授权和限制的法规》(Registration,Evaluation,Authorization and Restriction of Chemicals,REACH)管控要求越发严苛,作为直接接触人体皮肤产品的纺织品,需要对其高度关注物质(substances of very high concern,SVHC)残留情况进行检测,因此研究适用于纺织品基质复杂的SVHC筛查方法十分必要。针对纺织品基质复杂、SVHC种类多样以及传统的前处理方法耗时费力等问题,采用QuEChERS(quick、easy、cheap、eff ective、rugged、safe)前处理结合超高效液相色谱串联质谱(UPLC-MS/MS)的方法建立了一种纺织品SVHC快速筛查方法,通过优化前处理参数、色谱-质谱条件等手段对方法的线性范围、检出限(lower detection quantity,LOD)、定量限(lower quantification limit,LOQ)、回收率及精密度进行考查并应用于实际纺织品样品的筛查。研究表明,该方法具有简单快捷、灵敏度高、抗基质干扰能力强等特点,能适用于多种SVHC的纺织品筛查。
基金supported by the National Key Research and Development Program of China(Grant No.2023YFC3209504)the National Natural Science Foundation of China(Grants No.U2040215 and 52479075)the Natural Science Foundation of Hubei Province(Grant No.2021CFA029).
文摘The backwater effect caused by tributary inflow can significantly elevate the water level profile upstream of a confluence point.However,the influence of mainstream and confluence discharges on the backwater effect in a river reach remains unclear.In this study,various hydrological data collected from the Jingjiang Reach of the Yangtze River in China were statistically analyzed to determine the backwater degree and range with three representative mainstream discharges.The results indicated that the backwater degree increased with mainstream discharge,and a positive relationship was observed between the runoff ratio and backwater degree at specific representative mainstream discharges.Following the operation of the Three Gorges Project,the backwater effect in the Jingjiang Reach diminished.For instance,mean backwater degrees for low,moderate,and high mainstream discharges were recorded as 0.83 m,1.61 m,and 2.41 m during the period from 1990 to 2002,whereas these values decreased to 0.30 m,0.95 m,and 2.08 m from 2009 to 2020.The backwater range extended upstream as mainstream discharge increased from 7000 m3/s to 30000 m3/s.Moreover,a random forest-based machine learning model was used to quantify the backwater effect with varying mainstream and confluence discharges,accounting for the impacts of mainstream discharge,confluence discharge,and channel degradation in the Jingjiang Reach.At the Jianli Hydrological Station,a decrease in mainstream discharge during flood seasons resulted in a 7%–15%increase in monthly mean backwater degree,while an increase in mainstream discharge during dry seasons led to a 1%–15%decrease in monthly mean backwater degree.Furthermore,increasing confluence discharge from Dongting Lake during June to July and September to November resulted in an 11%–42%increase in monthly mean backwater degree.Continuous channel degradation in the Jingjiang Reach contributed to a 6%–19%decrease in monthly mean backwater degree.Under the influence of these factors,the monthly mean backwater degree in 2017 varied from a decrease of 53%to an increase of 37%compared to corresponding values in 1991.
文摘With accelerated expansion,the Shanghai Cooperation Organization(SCO)has extended its geographical reach to the vast Eurasian region,where the balance of power has undergone profound changes since the end of the Cold War,showing instability and uncertainty.The type of order that can emerge in a region depends on the effectiveness of governance and the power structures and systems built upon it.The SCO advocates a brand new philosophy of cooperation that transcends the traditional mentality of international relations,forging a new model of multilateral collaboration.The SCO has vigorously participated in improving regional governance and is thus playing an increasingly important and unique role in reshaping the Eurasian regional order.
文摘This paper introduces a novel chattering-free terminal sliding mode control(SMC)strategy to address chaotic behavior in permanent magnet synchronous generators(PMSG)for offshore wind turbine systems.By integrating an adaptive exponential reaching law with a continuous barrier function,the proposed approach eliminates chattering and ensures robust performance under model uncertainties.The methodology combines adaptive SMC with dynamic switching to estimate and compensates for unknown uncertainties,providing smooth and stable control.Finally,the performance and effectiveness of the proposed approach are compared with those of a previous study.
