Lightweight structures for gears enable a reduction in material usage while maintaining the technical function of the gear.Previous approaches have pursued the strategy of lightweight structures in the gear wheel body...Lightweight structures for gears enable a reduction in material usage while maintaining the technical function of the gear.Previous approaches have pursued the strategy of lightweight structures in the gear wheel body.By taking inspiration from biological models and utilizing material savings in the gear rim,new design approaches for the lightweight design of gears can be realized.For this reason,a holistic biological design approach for spur gears is presented.In addition to the method of topology optimization,a biologically inspired approach based on diatoms is introduced,which achieves a weight reduction of over 50%compared to conventional solid gears.Diatom structures are extracted from the oceans,digitally modelled,and adapted to the load conditions of a reference gear by parametric design and simulation optimization.For the experimental validation of the design,a manufactured gear is statically loaded in the nominal load range and analyzed using a tactile geometry gear measurement.The measurement results of selected standard gear parameters show that the gear does not exhibit any plastic deformation for the nominal load capacity of 383 Nm,validating the presented design approach.展开更多
Microplastics(MPs)have garnered significant international scrutiny as an emerging environmental pollutant,constituting one of the four principal global environmental threats and posing potential health hazards to huma...Microplastics(MPs)have garnered significant international scrutiny as an emerging environmental pollutant,constituting one of the four principal global environmental threats and posing potential health hazards to humans.However,data on the impact of MPs on the early life of the commercially important fish remain limited.In this study,polystyrene microspheres(PS-MPs)(1 and 5μm)were used to investigate the effects of MPs on the growth,development,and metabolism in early life stages of large yellow croaker Pseudosciaena crocea.Results indicate that MPs were enriched in the gastrointestinal tract and gills of the fish.In addition,PS-MPs(1μm)exhibited no obvious effects on embryo hatching and heart rates,while increased the mortality rate(23.00%vs.control 14.99%)and decreased the body length(4098.61±447.03μm vs.control with 2827.04±254.75μm)of the larvae at the highest exposure concentration(5×10^(4)items/L).Metabolomics analysis revealed that PS-MPs(5μm)induced mild perturbations in phospholipid metabolism,specifically alterations in phosphatidylethanolamine(PE)levels.These changes influenced the cell membranes of juvenile fish,and consequently elicited inflammatory responses,disrupted lipid homeostasis,and affected other critical physiological processes.Ultimately,these effects may avoid the growth retardation and potential mortality.Therefore,PS-MPs could affect negatively the fish health in the early life stage,which has implications for aquatic ecosystems.展开更多
The Arctic is one of Earth’s regions highly susceptible to climate change.However,in situ long-term observations used for climate research are relatively sparse in the Arctic Ocean,and current climate models exhibit ...The Arctic is one of Earth’s regions highly susceptible to climate change.However,in situ long-term observations used for climate research are relatively sparse in the Arctic Ocean,and current climate models exhibit notable biases in Arctic Ocean simulations.Here,we present an Arctic Ocean dynamical downscaling dataset,obtained from the global ocean-sea ice model FESOM2 with a regionally refined horizonal resolution of 4.5 km in the Arctic region,which is driven by bias-corrected surface forcings derived from a climate model.The dataset includes 115 years(1900-2014)of historical simulations and two 86-year future projection simulations(2015-2100)for the SSP2-4.5 and SSP5-8.5 scenarios.The historical simulations demonstrate substantially reduced biases in temperature,salinity and sea-ice thickness compared to CMIP6 climate models.Common biases in the representation of the Atlantic Water layer found in climate model simulations are also markedly reduced in the dataset.Serving as a crucial long-term data source for climate change assessments and scientific research for the Arctic Ocean,this dataset provides valuable information for the scientific community.展开更多
通过对可可西里库赛湖KS-2006孔矿物组合的分析表明:库赛湖沉积的碳酸盐为以文石为主的自生碳酸盐,其含量的高低能够指示温度的变化;盐类矿物只是在2150 cal aBP以来才出现,表明湖水盐度增高,与此同时,石英含量的持续增高可能同冷干气...通过对可可西里库赛湖KS-2006孔矿物组合的分析表明:库赛湖沉积的碳酸盐为以文石为主的自生碳酸盐,其含量的高低能够指示温度的变化;盐类矿物只是在2150 cal aBP以来才出现,表明湖水盐度增高,与此同时,石英含量的持续增高可能同冷干气候条件下该区风成活动的加强有关.青藏高原北部晚全新世的气候环境演化过程为:3770-2550 cal aBP期间气候条件整体较为温暖;2550-2150 cal aBP期间,气温缓慢下降有变冷的趋势;约2150 cal aBP至今,气候迅速转冷,湖区湿度降低,湖水盐度增高,风成活动加强,但900-700 cal aBP期间,为明显的温暖时期.展开更多
基金funded by the Federal Ministry for Economic Affairs and Climate Action as part of the Technology Transfer Program Lightweight Construction(Grant no.03LB1000A).
文摘Lightweight structures for gears enable a reduction in material usage while maintaining the technical function of the gear.Previous approaches have pursued the strategy of lightweight structures in the gear wheel body.By taking inspiration from biological models and utilizing material savings in the gear rim,new design approaches for the lightweight design of gears can be realized.For this reason,a holistic biological design approach for spur gears is presented.In addition to the method of topology optimization,a biologically inspired approach based on diatoms is introduced,which achieves a weight reduction of over 50%compared to conventional solid gears.Diatom structures are extracted from the oceans,digitally modelled,and adapted to the load conditions of a reference gear by parametric design and simulation optimization.For the experimental validation of the design,a manufactured gear is statically loaded in the nominal load range and analyzed using a tactile geometry gear measurement.The measurement results of selected standard gear parameters show that the gear does not exhibit any plastic deformation for the nominal load capacity of 383 Nm,validating the presented design approach.
基金Supported by the Pioneer and Leading Goose R&D Program of Zhejiang(No.2023C03130)the National Key R&D Program of China(No.2019YFD0901101)+4 种基金the National Natural Science Foundation of China(No.42076169)the Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(Nos.SL2022ZD203,SL2022MS012)the Zhejiang Provincial Natural Science Founds for Distinguished Young Scientists(No.LR21D060001)the State Key Laboratory of Satellite Ocean Environment Dynamics(No.SOEDZZ1902)the ChinaAPEC Cooperation Fund(No.2029901)。
文摘Microplastics(MPs)have garnered significant international scrutiny as an emerging environmental pollutant,constituting one of the four principal global environmental threats and posing potential health hazards to humans.However,data on the impact of MPs on the early life of the commercially important fish remain limited.In this study,polystyrene microspheres(PS-MPs)(1 and 5μm)were used to investigate the effects of MPs on the growth,development,and metabolism in early life stages of large yellow croaker Pseudosciaena crocea.Results indicate that MPs were enriched in the gastrointestinal tract and gills of the fish.In addition,PS-MPs(1μm)exhibited no obvious effects on embryo hatching and heart rates,while increased the mortality rate(23.00%vs.control 14.99%)and decreased the body length(4098.61±447.03μm vs.control with 2827.04±254.75μm)of the larvae at the highest exposure concentration(5×10^(4)items/L).Metabolomics analysis revealed that PS-MPs(5μm)induced mild perturbations in phospholipid metabolism,specifically alterations in phosphatidylethanolamine(PE)levels.These changes influenced the cell membranes of juvenile fish,and consequently elicited inflammatory responses,disrupted lipid homeostasis,and affected other critical physiological processes.Ultimately,these effects may avoid the growth retardation and potential mortality.Therefore,PS-MPs could affect negatively the fish health in the early life stage,which has implications for aquatic ecosystems.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFF0804600)the National Natural Science Foundation of China(Grant Nos.42276253 and 41821004)+1 种基金the Shandong Provincial Natural Science Foundation(Grant No.ZR2022JQ17)the Taishan Scholar Foundation of Shandong Province(Grant No.tsqn202211264).
文摘The Arctic is one of Earth’s regions highly susceptible to climate change.However,in situ long-term observations used for climate research are relatively sparse in the Arctic Ocean,and current climate models exhibit notable biases in Arctic Ocean simulations.Here,we present an Arctic Ocean dynamical downscaling dataset,obtained from the global ocean-sea ice model FESOM2 with a regionally refined horizonal resolution of 4.5 km in the Arctic region,which is driven by bias-corrected surface forcings derived from a climate model.The dataset includes 115 years(1900-2014)of historical simulations and two 86-year future projection simulations(2015-2100)for the SSP2-4.5 and SSP5-8.5 scenarios.The historical simulations demonstrate substantially reduced biases in temperature,salinity and sea-ice thickness compared to CMIP6 climate models.Common biases in the representation of the Atlantic Water layer found in climate model simulations are also markedly reduced in the dataset.Serving as a crucial long-term data source for climate change assessments and scientific research for the Arctic Ocean,this dataset provides valuable information for the scientific community.
文摘通过对可可西里库赛湖KS-2006孔矿物组合的分析表明:库赛湖沉积的碳酸盐为以文石为主的自生碳酸盐,其含量的高低能够指示温度的变化;盐类矿物只是在2150 cal aBP以来才出现,表明湖水盐度增高,与此同时,石英含量的持续增高可能同冷干气候条件下该区风成活动的加强有关.青藏高原北部晚全新世的气候环境演化过程为:3770-2550 cal aBP期间气候条件整体较为温暖;2550-2150 cal aBP期间,气温缓慢下降有变冷的趋势;约2150 cal aBP至今,气候迅速转冷,湖区湿度降低,湖水盐度增高,风成活动加强,但900-700 cal aBP期间,为明显的温暖时期.
