Monthly changes in the resin yield of semi-sib families of Pinus elliottii during 2013-2015 were studied.The results showed that from April to October,the resin yield of the P.elliottii families was the lowest in Apri...Monthly changes in the resin yield of semi-sib families of Pinus elliottii during 2013-2015 were studied.The results showed that from April to October,the resin yield of the P.elliottii families was the lowest in April and the highest in July.There were significant differences between various families in terms of resin yield.The change of resin yield was closely related to temperature,and the higher the temperature was,the higher the resin yield was.P.elliottii mainly produced resin from June to September.展开更多
Growth traits of semi-sib families of Pinus elliottii were studied.The results showed that there were extremely significant differences between the P.elliottii families in terms of tree height,DBH and volume( P < 0...Growth traits of semi-sib families of Pinus elliottii were studied.The results showed that there were extremely significant differences between the P.elliottii families in terms of tree height,DBH and volume( P < 0.01),and the families could be selected effectively.Both family heritability and single plant heritability of growth traits of P.elliottii were high.The family heritability of tree height,DBH and volume was 0.799,0.779 and 0.770 respectively,and their single plant heritability was 0.683,0.829 and 0.742 respectively.Among them,the family heritability of tree height was the highest,while the single plant heritability of DBH was the highest.The Duncan analysis of growth traits of the P.elliottii families revealed that families 12,7,15,4 and 6 were superior families and can be used as high-yield families.展开更多
This study examines wave reflection by a multi-chamber partially perforated caisson breakwater based on potential theory.A quadratic pressure drop boundary condition at perforated walls is adopted,which can well consi...This study examines wave reflection by a multi-chamber partially perforated caisson breakwater based on potential theory.A quadratic pressure drop boundary condition at perforated walls is adopted,which can well consider the effect of wave height on the wave dissipation by perforated walls.The matched eigenfunction expansions with iterative calculations are applied to develop an analytical solution for the present problem.The convergences of both the iterative calculations and the series solution itself are confirmed to be satisfactory.The calculation results of the present analytical solution are in excellent agreement with the numerical results of a multi-domain boundary element solution.Also,the predictions by the present solution are in reasonable agreement with experimental data in literature.Major factors that affect the reflection coefficient of the perforated caisson breakwater are examined by calculation examples.The analysis results show that the multi-chamber perforated caisson breakwater has a better wave energy dissipation function(lower reflection coefficient)than the single-chamber type over a broad range of wave frequency and may perform better if the perforated walls have larger porosities.When the porosities of the perforated walls decrease along the incident wave direction,the perforated caisson breakwater can achieve a lower reflection coefficient.The present analytical solution is simple and reliable,and it can be used as an efficient tool for analyzing the hydrodynamic performance of perforated breakwaters in preliminary engineering design.展开更多
Modern agriculture, based on the improved single-genotype crop varieties and the intensive and monocultural managements, has contributed tremendously to the world’s food supply. However, it is also challenged by stag...Modern agriculture, based on the improved single-genotype crop varieties and the intensive and monocultural managements, has contributed tremendously to the world’s food supply. However, it is also challenged by stagnant yield growth, increasingly high input, mounting environmental pollution and pressing sustainability of development. In comparison, old agriculture of 100 years ago, based on the traditional multi-genotype landraces and low-input cultivation, prevailed thousands of years and still exists now in subsistence farming in marginal areas in spite of its low productivity. Crop multi-genotype breeding, which combines the advantages of both old and modern agriculture at the high level of productivity, will give us a promising strategy to break the predicament of modern agriculture. The concept, necessity, principle, technical tactics and characteristics of crop multi-genotype breeding are first elucidated in detail here. Two successful cases of application in rice and cotton are presented. Firstly, rice multi-genotype inbred varieties (colony variety) have commercialized using MAGIC lines. In cotton, a multi-genotype hybrid variety Jing-Mi 1 revealed superiority in seeded cotton and lint yields over the check variety in regional trial. Multigenotype variety could be maintained and recover the genetic diversity in production system. In their progenies of the MAGIC lines, most of them could be transmitted to the multi-genotype varieties, implying that the genetic diversity of agro-ecosystem could be effectively restored by crop multi-genotype varieties. We believe crop multi-genotype breeding will make a substantial contribution to restoring genetic diversity of agro-ecosystem, preventing the exacerbation of vulnerable environment and promoting the sustainable development of agriculture. We call for ever-increasing efforts to develop and apply the crop multi-genotype breeding in agriculture.展开更多
The World Meteorological Organization estimates that about 90 percent of all natural disasters is extreme meteorological hazards like typhoon/hurricane and tropical cyclone triggered disasters. With the increasing ten...The World Meteorological Organization estimates that about 90 percent of all natural disasters is extreme meteorological hazards like typhoon/hurricane and tropical cyclone triggered disasters. With the increasing tendency of natural hazards, the typhoon induced surge, wave, precipitation, flood and wind as extreme external loads menacing Nuclear Power Plants (NPP) in coastal and inland provinces of China. For all of the planned, designed and constructed NPP in China the National Nuclear Safety Administration of China and IAEA recommended Probable Maximum Hurricane/ Typhoon/(PMH/T), Probable Maximum Storm Surge (PMSS), Probable Maximum Flood (PMF), Design Basis Flood (DBF) as safety regulations recommended for NPP defense infrastructures. This paper discusses the joint probability analysis of simultaneous occurrence typhoon induced extreme external hazards and compared with IAEA 2003-2011 recommended safety regulations for some NPP along China coast to make safety assessment based on the “As Low As Reasonable Practice” (ALARP) principle.展开更多
In this study, we investigated the effects of dexamethasone, pertussis toxin （a Gi protein inhibitor） and actinomycin （a transcription inhibitor） on serum nitric oxide synthase activity and nitric oxide content in...In this study, we investigated the effects of dexamethasone, pertussis toxin （a Gi protein inhibitor） and actinomycin （a transcription inhibitor） on serum nitric oxide synthase activity and nitric oxide content in a rat model of lung disease-induced brain injury. High-dose dexamethasone （13 mg/kg） and dexamethasone ＋ actinomycin reduced lung water content, increased serum nitric oxide synthase activity and nitric oxide content, diminished inflammatory cell infiltration in pulmonary alveolar interstitium, attenuated meningeal vascular hyperemia, reduced glial cell infiltration, and decreased cerebral edema. These results demonstrate that high-dose glucocorticoid treatment can reduce the severity of lung disease-induced brain injury by increasing nitric oxide synthase activity and nitric oxide levels.展开更多
The reversibility of lithium(Li) metal anodes is highly susceptible to temperature,owing to the aggravated side reactions at high temperatures and serious Li dendrite growth at low temperatures.Thus it is extremely ch...The reversibility of lithium(Li) metal anodes is highly susceptible to temperature,owing to the aggravated side reactions at high temperatures and serious Li dendrite growth at low temperatures.Thus it is extremely challenging to simultaneously realize the high Li reversibility in both low and high temperature scenarios.Herein,an oxygen-free solvent(n-hexane,HEX) assisted with the hexyl methyl ether and 1 mol L^(-1)lithium bis(fluorosulfonyl)imide is proposed to constitute an electrolyte for temperatureimmune lithium metal batteries.It demonstrates that the HEX not only greatly suppresses the solvent reduction even at high temperatures but also weaken the Li~+-solvent interaction for the facile Li-ion desolvation,leading to high Li Coulombic efficiencies(99.59% at 25℃,99.30%at 60℃ and 98.75% at -30℃) and the dendrite-free Li plating from -30℃ to 60℃.Benefitting from the low density and temperature-immune properties of our electrolyte,the sulfurized polyacrylonitrile(3.8mAh cm^(-2))||Li(60 μm) pouch-cells deliver 278 Wh kg^(-1)energy density and maintain the stable performance over 50 cycles,and retain 248 and 320 Wh kg^(-1) energy density at -30℃ and 60℃,respectively.This work provides a new perspective on the electrolyte design for wide-temperature Li metal batteries.展开更多
Using the multivision technique, a new void fraction measurement method was developed for bubble and slug flow in a small channel. The multivision system was developed to obtain images of the two-phase flow in two per...Using the multivision technique, a new void fraction measurement method was developed for bubble and slug flow in a small channel. The multivision system was developed to obtain images of the two-phase flow in two perpendicular directions. The obtained images were processed--using image segmentation, image subtraction, Canny edge detection, binarization, and hole filling-to extract the phase boundaries and information about the bubble or slug parameters, With the extracted information, a new void fraction measurement model was developed and used to determine the void fraction of the two-phase flow. The proposed method was validated experimentally in horizontal and vertical channels with different inner diameters of 2.1, 2.9, and 4.0 mm, The proposed method of measuring the void fraction has better performance than the methods that use images acquired in only one direction, with a maximum absolute difference between the measured and reference values of less than 6%.展开更多
The oceans are crucial to human civilization.They provide core support for exploitation and utilization of marine space,resources,and energy.Thus,marine infrastructures are vital to a nation’s economic sustainable de...The oceans are crucial to human civilization.They provide core support for exploitation and utilization of marine space,resources,and energy.Thus,marine infrastructures are vital to a nation’s economic sustainable development.To this end,this article first describes the main challenges in current ocean utilization,and then reviews the China’s ocean engineering progress.As such,six major sectors are evaluated:1)global climate change and marine environment,2)comprehensive utilization of marine space,3)marine transportation infrastructure interconnection,4)ocean clean energy development and maricultural facilities,5)ecological crisis and marine engineering countermeasures,and 6)marine infrastructure operation safety and maintenance.Finally,perspectives on future directions of ocean utilization and marine infrastructure construction in China are provided.展开更多
基金Supported by National Key Research and Development Plan(2017YFD0600502)Forestry Science and Technology Planning Project of Hunan Province,China(XLK201307-2)
文摘Monthly changes in the resin yield of semi-sib families of Pinus elliottii during 2013-2015 were studied.The results showed that from April to October,the resin yield of the P.elliottii families was the lowest in April and the highest in July.There were significant differences between various families in terms of resin yield.The change of resin yield was closely related to temperature,and the higher the temperature was,the higher the resin yield was.P.elliottii mainly produced resin from June to September.
基金Supported by National Key Research and Development Plan(2017YFD0600502)Forestry Science and Technology Planning Project of Hunan Province,China(XLK201307-2)
文摘Growth traits of semi-sib families of Pinus elliottii were studied.The results showed that there were extremely significant differences between the P.elliottii families in terms of tree height,DBH and volume( P < 0.01),and the families could be selected effectively.Both family heritability and single plant heritability of growth traits of P.elliottii were high.The family heritability of tree height,DBH and volume was 0.799,0.779 and 0.770 respectively,and their single plant heritability was 0.683,0.829 and 0.742 respectively.Among them,the family heritability of tree height was the highest,while the single plant heritability of DBH was the highest.The Duncan analysis of growth traits of the P.elliottii families revealed that families 12,7,15,4 and 6 were superior families and can be used as high-yield families.
基金The National Natural Science Foundation of China under contract Nos 51725903 and 51490675。
文摘This study examines wave reflection by a multi-chamber partially perforated caisson breakwater based on potential theory.A quadratic pressure drop boundary condition at perforated walls is adopted,which can well consider the effect of wave height on the wave dissipation by perforated walls.The matched eigenfunction expansions with iterative calculations are applied to develop an analytical solution for the present problem.The convergences of both the iterative calculations and the series solution itself are confirmed to be satisfactory.The calculation results of the present analytical solution are in excellent agreement with the numerical results of a multi-domain boundary element solution.Also,the predictions by the present solution are in reasonable agreement with experimental data in literature.Major factors that affect the reflection coefficient of the perforated caisson breakwater are examined by calculation examples.The analysis results show that the multi-chamber perforated caisson breakwater has a better wave energy dissipation function(lower reflection coefficient)than the single-chamber type over a broad range of wave frequency and may perform better if the perforated walls have larger porosities.When the porosities of the perforated walls decrease along the incident wave direction,the perforated caisson breakwater can achieve a lower reflection coefficient.The present analytical solution is simple and reliable,and it can be used as an efficient tool for analyzing the hydrodynamic performance of perforated breakwaters in preliminary engineering design.
文摘Modern agriculture, based on the improved single-genotype crop varieties and the intensive and monocultural managements, has contributed tremendously to the world’s food supply. However, it is also challenged by stagnant yield growth, increasingly high input, mounting environmental pollution and pressing sustainability of development. In comparison, old agriculture of 100 years ago, based on the traditional multi-genotype landraces and low-input cultivation, prevailed thousands of years and still exists now in subsistence farming in marginal areas in spite of its low productivity. Crop multi-genotype breeding, which combines the advantages of both old and modern agriculture at the high level of productivity, will give us a promising strategy to break the predicament of modern agriculture. The concept, necessity, principle, technical tactics and characteristics of crop multi-genotype breeding are first elucidated in detail here. Two successful cases of application in rice and cotton are presented. Firstly, rice multi-genotype inbred varieties (colony variety) have commercialized using MAGIC lines. In cotton, a multi-genotype hybrid variety Jing-Mi 1 revealed superiority in seeded cotton and lint yields over the check variety in regional trial. Multigenotype variety could be maintained and recover the genetic diversity in production system. In their progenies of the MAGIC lines, most of them could be transmitted to the multi-genotype varieties, implying that the genetic diversity of agro-ecosystem could be effectively restored by crop multi-genotype varieties. We believe crop multi-genotype breeding will make a substantial contribution to restoring genetic diversity of agro-ecosystem, preventing the exacerbation of vulnerable environment and promoting the sustainable development of agriculture. We call for ever-increasing efforts to develop and apply the crop multi-genotype breeding in agriculture.
文摘The World Meteorological Organization estimates that about 90 percent of all natural disasters is extreme meteorological hazards like typhoon/hurricane and tropical cyclone triggered disasters. With the increasing tendency of natural hazards, the typhoon induced surge, wave, precipitation, flood and wind as extreme external loads menacing Nuclear Power Plants (NPP) in coastal and inland provinces of China. For all of the planned, designed and constructed NPP in China the National Nuclear Safety Administration of China and IAEA recommended Probable Maximum Hurricane/ Typhoon/(PMH/T), Probable Maximum Storm Surge (PMSS), Probable Maximum Flood (PMF), Design Basis Flood (DBF) as safety regulations recommended for NPP defense infrastructures. This paper discusses the joint probability analysis of simultaneous occurrence typhoon induced extreme external hazards and compared with IAEA 2003-2011 recommended safety regulations for some NPP along China coast to make safety assessment based on the “As Low As Reasonable Practice” (ALARP) principle.
文摘In this study, we investigated the effects of dexamethasone, pertussis toxin （a Gi protein inhibitor） and actinomycin （a transcription inhibitor） on serum nitric oxide synthase activity and nitric oxide content in a rat model of lung disease-induced brain injury. High-dose dexamethasone （13 mg/kg） and dexamethasone ＋ actinomycin reduced lung water content, increased serum nitric oxide synthase activity and nitric oxide content, diminished inflammatory cell infiltration in pulmonary alveolar interstitium, attenuated meningeal vascular hyperemia, reduced glial cell infiltration, and decreased cerebral edema. These results demonstrate that high-dose glucocorticoid treatment can reduce the severity of lung disease-induced brain injury by increasing nitric oxide synthase activity and nitric oxide levels.
基金supported by CAS Youth Interdisciplinary TeamChina Postdoctoral Science Foundation (2021M703318, 2022T150671)。
文摘The reversibility of lithium(Li) metal anodes is highly susceptible to temperature,owing to the aggravated side reactions at high temperatures and serious Li dendrite growth at low temperatures.Thus it is extremely challenging to simultaneously realize the high Li reversibility in both low and high temperature scenarios.Herein,an oxygen-free solvent(n-hexane,HEX) assisted with the hexyl methyl ether and 1 mol L^(-1)lithium bis(fluorosulfonyl)imide is proposed to constitute an electrolyte for temperatureimmune lithium metal batteries.It demonstrates that the HEX not only greatly suppresses the solvent reduction even at high temperatures but also weaken the Li~+-solvent interaction for the facile Li-ion desolvation,leading to high Li Coulombic efficiencies(99.59% at 25℃,99.30%at 60℃ and 98.75% at -30℃) and the dendrite-free Li plating from -30℃ to 60℃.Benefitting from the low density and temperature-immune properties of our electrolyte,the sulfurized polyacrylonitrile(3.8mAh cm^(-2))||Li(60 μm) pouch-cells deliver 278 Wh kg^(-1)energy density and maintain the stable performance over 50 cycles,and retain 248 and 320 Wh kg^(-1) energy density at -30℃ and 60℃,respectively.This work provides a new perspective on the electrolyte design for wide-temperature Li metal batteries.
文摘Using the multivision technique, a new void fraction measurement method was developed for bubble and slug flow in a small channel. The multivision system was developed to obtain images of the two-phase flow in two perpendicular directions. The obtained images were processed--using image segmentation, image subtraction, Canny edge detection, binarization, and hole filling-to extract the phase boundaries and information about the bubble or slug parameters, With the extracted information, a new void fraction measurement model was developed and used to determine the void fraction of the two-phase flow. The proposed method was validated experimentally in horizontal and vertical channels with different inner diameters of 2.1, 2.9, and 4.0 mm, The proposed method of measuring the void fraction has better performance than the methods that use images acquired in only one direction, with a maximum absolute difference between the measured and reference values of less than 6%.
基金The authors would like to acknowledge the National Natural Science Foundation of China’s Basic Science Center Project(Grant No.52088102)for supporting the research work of this article.
文摘The oceans are crucial to human civilization.They provide core support for exploitation and utilization of marine space,resources,and energy.Thus,marine infrastructures are vital to a nation’s economic sustainable development.To this end,this article first describes the main challenges in current ocean utilization,and then reviews the China’s ocean engineering progress.As such,six major sectors are evaluated:1)global climate change and marine environment,2)comprehensive utilization of marine space,3)marine transportation infrastructure interconnection,4)ocean clean energy development and maricultural facilities,5)ecological crisis and marine engineering countermeasures,and 6)marine infrastructure operation safety and maintenance.Finally,perspectives on future directions of ocean utilization and marine infrastructure construction in China are provided.
