On 19 June 2023,the Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction(BBNJ Agreement)was a...On 19 June 2023,the Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction(BBNJ Agreement)was adopted.The BBNJ Agreement aims to regulate the conservation and sustainable use of marine biodiversity in areas beyond national jurisdiction,including the high seas and the international seabed area.The BBNJ Agreement enters into an already crowded institutional landscape as a global authority with broad objectives,inevitably interacting with existing institutions,frameworks,and bodies(IFBs).Existing research has primarily focused on two areas:the first examines the impact of the institutions established by the BBNJ Agreement on existing marine governance IFBs;the second explores its influence on issues currently lacking institutional arrangements.However,comparatively little attention has been given to the Agreement’s potential impact on governance gaps within established systems.This paper takes the case of marine genetic resource(MGRs)management in the Antarctic Treaty Area to explore how the BBNJ Agreement may address regulatory gaps in a competent governance framework.Due to shortcomings in addressing core issues,concerning the legal status of MGRs access regulations,benefit-sharing mechanisms,and disclosure of origin,the Agreement is unlikely to have a significant impact on the governance of MGRs in the Antarctic Treaty System(ATS)in the short term.On the other hand,the ATS,as an effective governance framework for the Antarctic Treaty Area,has mature regulations and practical experience in Antarctic governance.Over the years,the ATS has focused on regulating bioprospecting activities as scientific research ones and strict environmental impact assessment procedures.However,there has not been an effective consensus on the regulation of commercial biological prospecting.This paper further explores the coordination issue between the BBNJ Agreement and the ATS,suggesting that in the future,MGRs governance in the Antarctic Treaty Area may evolve into a polycentric governance system.展开更多
在保障广播电视机房正常运行方面,机房的备用供电系统发挥了重要作用,其能够有效避免因突发电路故障导致安全播出事故。结合不间断电源(Uninterruptible Power Supply,UPS)的技术原理和特点,按照UPS与双电源自动切换开关(Automatic Tran...在保障广播电视机房正常运行方面,机房的备用供电系统发挥了重要作用,其能够有效避免因突发电路故障导致安全播出事故。结合不间断电源(Uninterruptible Power Supply,UPS)的技术原理和特点,按照UPS与双电源自动切换开关(Automatic Transfer Switch,ATS)组合应用的设计思路,提出一种基于单一ATS双电源接线模式的广播电视机房UPS系统改造方案。该方案旨在确保广播信号安全顺畅传输的基础上,有效降低备用供电系统的建设成本和运维成本。展开更多
The remodeling of root architecture is a major developmental response of plants to phosphate （Pi） deficiency and is thought to enhance a plant＇s ability to forage for the available Pi in topsoil. The underlying mec...The remodeling of root architecture is a major developmental response of plants to phosphate （Pi） deficiency and is thought to enhance a plant＇s ability to forage for the available Pi in topsoil. The underlying mechanism controlling this response, however, is poorly understood. In this study, we identified an Arabidopsis mutant, hps 10 （hypersensitive to Pi starvation 10）, which is morphologically normal under Pi sufficient condition but shows increased inhibition of primary root growth and enhanced production of lateral roots under Pi defi- ciency, hpslO is a previously identified allele （als3-3） of the ALUMINUM SENSITIVE3 （ALS3） gene, which is involved in plant tolerance to aluminum toxicity. Our results show that ALS3 and its interacting protein AtSTAR1 form an ABC transporter complex in the tonoplast. This protein complex mediates a highly electro- genic transport in Xenopus oocytes. Under Pi deficiency, als3 accumulates higher levels of Fe3＋ in its roots than the wild type does. In Arabidopsis, LPR1 （LOW PHOSPHATE ROOT1） and LPR2 encode ferroxidases, which when mutated, reduce Fe3＋ accumulation in roots and cause root growth to be insensitive to Pi defi- ciency. Here, we provide compelling evidence showing that ALS3 cooperates with LPR1/2 to regulate Pi deficiency-induced remodeling of root architecture by modulating Fe homeostasis in roots.展开更多
针对油浸式电力变压器瞬态温升计算效率过低的问题,该文提出本征正交分解-αATS(proper orthogonal decomposition-adaptive time stepping based onαfactor,POD-αATS)降阶自适应变步长瞬态计算方法。首先,推导变压器绕组瞬态温升计...针对油浸式电力变压器瞬态温升计算效率过低的问题,该文提出本征正交分解-αATS(proper orthogonal decomposition-adaptive time stepping based onαfactor,POD-αATS)降阶自适应变步长瞬态计算方法。首先,推导变压器绕组瞬态温升计算的有限元离散方程;其次,采用POD降阶算法改善传统瞬态计算中存在的条件数过大及方程阶数过高的问题;同时对于瞬态计算中的时间步长选择问题,提出适用于非线性问题的αATS变步长策略;然后,为验证方法的有效性,基于110 kV油浸式电力变压器绕组的基本结构建立二维八分区数值计算模型,同时将计算结果与基于110 kV绕组的温升实验结果进行对比。数值计算及实验结果表明,所提算法与全阶定步长算法在流场和温度场中的精度几乎相同,且流场计算效率提升约45倍,温度场计算效率提升约38倍,计算速度得到显著提高。这一点在温升实验中同样得到验证,说明该文所提算法的准确性、高效性及一定的工程实用性。展开更多
Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect o...Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect of temperature on land subsidence has received practically no attention in the past.This paper presents a thermo-hydro-mechanical(THM)coupled numerical study on an ATES system in Shanghai,China.Four water wells were installed for seasonal heating and cooling of an agriculture greenhouse.The target aquifer at a depth of 74e104.5 m consisted of alternating layers of sand and silty sand and was covered with clay.Groundwater level,temperature,and land subsidence data from 2015 to 2017 were collected using field monitoring instruments.Constrained by data,we constructed a field scale three-dimensional(3D)model using TOUGH(Transport of Unsaturated Groundwater and Heat)and FLAC3D(Fast Lagrangian Analysis of Continua)equipped with a thermo-elastoplastic constitutive model.The effectiveness of the numerical model was validated by field data.The model was used to reproduce groundwater flow,heat transfer,and mechanical responses in porous media over three years and capture the thermo-and pressure-induced land subsidence.The results show that the maximum thermoinduced land subsidence accounts for about 60%of the total subsidence.The thermo-induced subsidence is slightly greater in winter than that in summer,and more pronounced near the cold well area than the hot well area.This study provides some valuable guidelines for controlling land subsidence caused by ATES systems installed in soft soils.展开更多
基金funded by China Arctic and Antarctic Administration(Contract no.JDB2024060701014).
文摘On 19 June 2023,the Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction(BBNJ Agreement)was adopted.The BBNJ Agreement aims to regulate the conservation and sustainable use of marine biodiversity in areas beyond national jurisdiction,including the high seas and the international seabed area.The BBNJ Agreement enters into an already crowded institutional landscape as a global authority with broad objectives,inevitably interacting with existing institutions,frameworks,and bodies(IFBs).Existing research has primarily focused on two areas:the first examines the impact of the institutions established by the BBNJ Agreement on existing marine governance IFBs;the second explores its influence on issues currently lacking institutional arrangements.However,comparatively little attention has been given to the Agreement’s potential impact on governance gaps within established systems.This paper takes the case of marine genetic resource(MGRs)management in the Antarctic Treaty Area to explore how the BBNJ Agreement may address regulatory gaps in a competent governance framework.Due to shortcomings in addressing core issues,concerning the legal status of MGRs access regulations,benefit-sharing mechanisms,and disclosure of origin,the Agreement is unlikely to have a significant impact on the governance of MGRs in the Antarctic Treaty System(ATS)in the short term.On the other hand,the ATS,as an effective governance framework for the Antarctic Treaty Area,has mature regulations and practical experience in Antarctic governance.Over the years,the ATS has focused on regulating bioprospecting activities as scientific research ones and strict environmental impact assessment procedures.However,there has not been an effective consensus on the regulation of commercial biological prospecting.This paper further explores the coordination issue between the BBNJ Agreement and the ATS,suggesting that in the future,MGRs governance in the Antarctic Treaty Area may evolve into a polycentric governance system.
文摘在保障广播电视机房正常运行方面,机房的备用供电系统发挥了重要作用,其能够有效避免因突发电路故障导致安全播出事故。结合不间断电源(Uninterruptible Power Supply,UPS)的技术原理和特点,按照UPS与双电源自动切换开关(Automatic Transfer Switch,ATS)组合应用的设计思路,提出一种基于单一ATS双电源接线模式的广播电视机房UPS系统改造方案。该方案旨在确保广播信号安全顺畅传输的基础上,有效降低备用供电系统的建设成本和运维成本。
文摘The remodeling of root architecture is a major developmental response of plants to phosphate （Pi） deficiency and is thought to enhance a plant＇s ability to forage for the available Pi in topsoil. The underlying mechanism controlling this response, however, is poorly understood. In this study, we identified an Arabidopsis mutant, hps 10 （hypersensitive to Pi starvation 10）, which is morphologically normal under Pi sufficient condition but shows increased inhibition of primary root growth and enhanced production of lateral roots under Pi defi- ciency, hpslO is a previously identified allele （als3-3） of the ALUMINUM SENSITIVE3 （ALS3） gene, which is involved in plant tolerance to aluminum toxicity. Our results show that ALS3 and its interacting protein AtSTAR1 form an ABC transporter complex in the tonoplast. This protein complex mediates a highly electro- genic transport in Xenopus oocytes. Under Pi deficiency, als3 accumulates higher levels of Fe3＋ in its roots than the wild type does. In Arabidopsis, LPR1 （LOW PHOSPHATE ROOT1） and LPR2 encode ferroxidases, which when mutated, reduce Fe3＋ accumulation in roots and cause root growth to be insensitive to Pi defi- ciency. Here, we provide compelling evidence showing that ALS3 cooperates with LPR1/2 to regulate Pi deficiency-induced remodeling of root architecture by modulating Fe homeostasis in roots.
文摘针对油浸式电力变压器瞬态温升计算效率过低的问题,该文提出本征正交分解-αATS(proper orthogonal decomposition-adaptive time stepping based onαfactor,POD-αATS)降阶自适应变步长瞬态计算方法。首先,推导变压器绕组瞬态温升计算的有限元离散方程;其次,采用POD降阶算法改善传统瞬态计算中存在的条件数过大及方程阶数过高的问题;同时对于瞬态计算中的时间步长选择问题,提出适用于非线性问题的αATS变步长策略;然后,为验证方法的有效性,基于110 kV油浸式电力变压器绕组的基本结构建立二维八分区数值计算模型,同时将计算结果与基于110 kV绕组的温升实验结果进行对比。数值计算及实验结果表明,所提算法与全阶定步长算法在流场和温度场中的精度几乎相同,且流场计算效率提升约45倍,温度场计算效率提升约38倍,计算速度得到显著提高。这一点在温升实验中同样得到验证,说明该文所提算法的准确性、高效性及一定的工程实用性。
基金sponsored by the National Key Research and Development Program of China(Grant No.2020YFC1808102).
文摘Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect of temperature on land subsidence has received practically no attention in the past.This paper presents a thermo-hydro-mechanical(THM)coupled numerical study on an ATES system in Shanghai,China.Four water wells were installed for seasonal heating and cooling of an agriculture greenhouse.The target aquifer at a depth of 74e104.5 m consisted of alternating layers of sand and silty sand and was covered with clay.Groundwater level,temperature,and land subsidence data from 2015 to 2017 were collected using field monitoring instruments.Constrained by data,we constructed a field scale three-dimensional(3D)model using TOUGH(Transport of Unsaturated Groundwater and Heat)and FLAC3D(Fast Lagrangian Analysis of Continua)equipped with a thermo-elastoplastic constitutive model.The effectiveness of the numerical model was validated by field data.The model was used to reproduce groundwater flow,heat transfer,and mechanical responses in porous media over three years and capture the thermo-and pressure-induced land subsidence.The results show that the maximum thermoinduced land subsidence accounts for about 60%of the total subsidence.The thermo-induced subsidence is slightly greater in winter than that in summer,and more pronounced near the cold well area than the hot well area.This study provides some valuable guidelines for controlling land subsidence caused by ATES systems installed in soft soils.
