Solar-driven desalination is a promising way to alleviate the freshwater shortage,while is facing challenges posed by low evaporation rates and severe salt accumulation.Herein,a high-performance twodimensional(2D) sol...Solar-driven desalination is a promising way to alleviate the freshwater shortage,while is facing challenges posed by low evaporation rates and severe salt accumulation.Herein,a high-performance twodimensional(2D) solar absorber with Co_(3)O_(4) nanoneedle arrays(Co_(3)O_(4)-NN) grown on the surface of reduced graphene oxide-coated pyrolyzed silk cloth(Co_(3)O_(4)-NN/rGO/PSC) was prepared,and a salt-free evaporator system was assembled based on the composite material and siphonage-the flowing water delivery.It is revealed that the evaporation enthalpy of water can be reduced over the 2D solar absorber grown with Co_(3)O_(4)-NN_T enabling an evaporation rate of up to 2.35 kg m^(-2) h^(-1) in DI water under one solar irradiation.The desalination process can be carried out continuously even with salt concentration up to 20 wt%,due to the timely removal of concentrated brine from the interface with the assistance of directed flowing water.Moreover,the 2D structure and the flowing water also provide an opportunity to convert waste solar heat into electricity in the evaporator based on the seebeck effect,ensuring simultaneous freshwater production and power generation.It is believed that this work provides insights into designing hybrid systems with high evaporation rate,salt resistance,and electricity generation.展开更多
Regional development strategies that align with urban characteristics and the sci-entific allocation of construction land indicators can effectively guide the high-quality coordi-nated development of urban agglomerati...Regional development strategies that align with urban characteristics and the sci-entific allocation of construction land indicators can effectively guide the high-quality coordi-nated development of urban agglomerations.However,the issue of whether urbanization matches the development strategy has always lacked an in-depth response in geography.Moreover,along with the urbanization process,the land limitation for agricultural and eco-logical spaces becomes increasingly strict,and the availability of construction land indicators is increasingly constrained.The construction land allocation is thus critical for the distribution of regional resources and the development goals of urban agglomeration.Based on the prin-ciples of development geography and the core-periphery theory,this study comprehensively considered three subsystems of urbanization(population,economy,and land)and the spatial link intensity among cities within a certain region to analyze the impacts of"siphon"and"ra-diation"effects on regional development,and assessed whether China's two major regional urbanization strategies aligned the comprehensive development characteristics.Furthermore,the quantitative construction land allocation in Beijing-Tianjin-Hebei(BTH)and Yangtze River Delta(YRD)urban agglomerations was completed.The results showed that the urban com-prehensive level index(UCL)in core cities(Beijing and Tianjin)and peripheral cities differed significantly in BTH,demonstrating a clear core-periphery structure.Along with urbanization,the"siphon"effect in BTH was weakening.Beijing's urban primacy decreased and the growth rate of UCL decreased from 53.89%in the first five years to 18.37%in the last five years during the study period(2020-2019).In contrast,the"radiation"effect in YRD was more ob-vious,exhibiting a development pattern driven by multiple growth poles.Temporally,the BTH indicated a coordinated development trend,while the integration level of YRD continued to strengthen.Compared to the top-down construction land allocated by the government,the results of quantitative allocation in this study reduced volatility.This study confirms the scientific basis of the coordinated development for BTH and the integrated regional development strategy for YRD from the perspective of development geography.It also provides a practical reference fortheconstructionland allocation.展开更多
基金the financial support from the National Natural Science Foundation of China (Grant No. 52172038, 22179017)National Key Research and Development Program of China (Nos. 2022YFB4101600, 2022YFB4101601)。
文摘Solar-driven desalination is a promising way to alleviate the freshwater shortage,while is facing challenges posed by low evaporation rates and severe salt accumulation.Herein,a high-performance twodimensional(2D) solar absorber with Co_(3)O_(4) nanoneedle arrays(Co_(3)O_(4)-NN) grown on the surface of reduced graphene oxide-coated pyrolyzed silk cloth(Co_(3)O_(4)-NN/rGO/PSC) was prepared,and a salt-free evaporator system was assembled based on the composite material and siphonage-the flowing water delivery.It is revealed that the evaporation enthalpy of water can be reduced over the 2D solar absorber grown with Co_(3)O_(4)-NN_T enabling an evaporation rate of up to 2.35 kg m^(-2) h^(-1) in DI water under one solar irradiation.The desalination process can be carried out continuously even with salt concentration up to 20 wt%,due to the timely removal of concentrated brine from the interface with the assistance of directed flowing water.Moreover,the 2D structure and the flowing water also provide an opportunity to convert waste solar heat into electricity in the evaporator based on the seebeck effect,ensuring simultaneous freshwater production and power generation.It is believed that this work provides insights into designing hybrid systems with high evaporation rate,salt resistance,and electricity generation.
基金National Natural Science Foundation of China,No.42071415Xinyang Academy of Ecological Research Open Foundation,No.2023XYMS01Central Plains Youth Top Talent Project。
文摘Regional development strategies that align with urban characteristics and the sci-entific allocation of construction land indicators can effectively guide the high-quality coordi-nated development of urban agglomerations.However,the issue of whether urbanization matches the development strategy has always lacked an in-depth response in geography.Moreover,along with the urbanization process,the land limitation for agricultural and eco-logical spaces becomes increasingly strict,and the availability of construction land indicators is increasingly constrained.The construction land allocation is thus critical for the distribution of regional resources and the development goals of urban agglomeration.Based on the prin-ciples of development geography and the core-periphery theory,this study comprehensively considered three subsystems of urbanization(population,economy,and land)and the spatial link intensity among cities within a certain region to analyze the impacts of"siphon"and"ra-diation"effects on regional development,and assessed whether China's two major regional urbanization strategies aligned the comprehensive development characteristics.Furthermore,the quantitative construction land allocation in Beijing-Tianjin-Hebei(BTH)and Yangtze River Delta(YRD)urban agglomerations was completed.The results showed that the urban com-prehensive level index(UCL)in core cities(Beijing and Tianjin)and peripheral cities differed significantly in BTH,demonstrating a clear core-periphery structure.Along with urbanization,the"siphon"effect in BTH was weakening.Beijing's urban primacy decreased and the growth rate of UCL decreased from 53.89%in the first five years to 18.37%in the last five years during the study period(2020-2019).In contrast,the"radiation"effect in YRD was more ob-vious,exhibiting a development pattern driven by multiple growth poles.Temporally,the BTH indicated a coordinated development trend,while the integration level of YRD continued to strengthen.Compared to the top-down construction land allocated by the government,the results of quantitative allocation in this study reduced volatility.This study confirms the scientific basis of the coordinated development for BTH and the integrated regional development strategy for YRD from the perspective of development geography.It also provides a practical reference fortheconstructionland allocation.
