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Analysis of the Conditional Correlations from Different Genetic Systems Between the Protein Content and the Appearance Quality Traits of Indica Rice 被引量:4
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作者 葛国科 郑希 +2 位作者 吴建国 叶子弘 石春海 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第2期129-137,共9页
A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines (A) and 5 restorer lines (R) along with their F1 (A × R) and F2 populations. The unconditional and conditio... A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines (A) and 5 restorer lines (R) along with their F1 (A × R) and F2 populations. The unconditional and conditional analyses of genetic models and the corresponding statistic methods, including endospermic, cytoplasmic, and maternal plant genetic systems, were used to analyze the genetic relationships between protein content (PC) and the appearance quality traits of indica rice (Oryza sativa L.). The results from unconditional analysis indicated that PC was significantly correlated with the appearance quality traits of rice, except for the brown rice thickness (BRT). Only the genetic covariance between PC and the brown rice width (BRW) was positively correlative, whereas all the other pairwise traits were negatively correlative. The results from conditional analysis revealed that the weight of brown rice (WBR) or the amylose content (AC) could significantly affect the relationships between PC and the appearance quality traits of indica rice. The conditional analysis showed that WBR might negatively affect the relationships between PC and the brown rice length (BRL), BRW, or BRT through the geuotype x environmental (GE) interaction effects, but positively affected the relationships between PC and the ratio of brown rice length to width (RLW) or the ratio of brown rice length to thickness (RLT). The amylase content could positively affect the relationships between PC and BRL, RLW, RLT through the cytoplasmic effects and maternal additive effects, but negatively affected the relationships between PC and BRW. 展开更多
关键词 indica rice (Oryza sativa L.) COVARIANCE unconditional and conditional analysis methods protein content amylose content appearance quality
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Mechanical properties and acoustic emission characteristics of soft rock with different water contents under dynamic disturbance 被引量:1
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作者 Yujing Jiang Lugen Chen +4 位作者 Dong Wang Hengjie Luan Guangchao Zhang Ling Dong Bin Liang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期135-148,共14页
Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties... Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties and acoustic emission characteristics of soft rocks with different water contents under dynamic disturbance.The mechanical properties and acoustic emission characteristics of muddy sandstones at different water contents were analysed.Results of experimental studies show that water is a key factor in the mechanical properties of rocks,softening them,increasing their porosity,reducing their brittleness and increasing their plasticity.Under uniaxial compression,the macroscopic damage characteristics of the muddy sandstone change from mono-bevel shear damage and‘X’type conjugate bevel shear damage to a roadway bottom-drum type damage as the water content increases.Dynamic perturbation has a strengthening effect on the mechanical properties of samples with 60%and less water content,and a weakening effect on samples with 80%and more water content,but the weakening effect is not obvious.Macroscopic damage characteristics of dry samples remain unchanged,water samples from shear damage and tensile–shear composite damage gradually transformed into cleavage damage,until saturation transformation monoclinic shear damage.The evolution of acoustic emission energy and event number is mainly divided into four stages:loading stage(Ⅰ),dynamic loading stage(Ⅱ),yield failure stage(Ⅲ),and post-peak stage(Ⅳ),the acoustic emission characteristics of the stages were different for different water contents.The characteristic value of acoustic emission key point frequency gradually decreases,and the damage degree of the specimen increases,corresponding to low water content—high main frequency—low damage and high water content—low main frequency—high damage. 展开更多
关键词 Dynamic disturbance Soft rock Cyclic loading Acoustic emission Water content
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Effect of sex and rearing system on the quality and mineral content of fiber from raeini cashmere goats 被引量:7
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作者 Mehrdad Shamsaddini-Bafti Mahnaz Salehi +3 位作者 Ali Maghsoudi Ali Mostafa Tehrani Farhad Mirzaei Syed Mojtaba Syed Momen 《Journal of Animal Science and Biotechnology》 SCIE CAS 2012年第3期160-165,共6页
The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (... The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (〈1.5 years of age, n=48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 um, 20.9±0.4%, 66.1 ± 1.5%, 33.8± 1.5% and 1.8±0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P 〈 0.05). 展开更多
关键词 cashmere fiber mineral contents Raeini goat
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Systematic analysis of components and contents in Houttuynia cordata Thunb 被引量:4
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作者 Xin-Yi Dong Yi Jin Li-Ping Yang 《Traditional Medicine Research》 2017年第4期176-188,共13页
Objective:This study aims to provide the material basis for the molecular mechanism of Yuxingcao(Houttuynia cordata Thunb,HCT)through the method of evidence-based study to summarize the natural constituents isolated f... Objective:This study aims to provide the material basis for the molecular mechanism of Yuxingcao(Houttuynia cordata Thunb,HCT)through the method of evidence-based study to summarize the natural constituents isolated from HCT.Methods:We searched CNKI,Wanfang,VIP,Pubmed and relevant conference compilations.The keywords were'Yuxingcao or Houttuynia cordata Thunb'and'components'or'ingredients'or'constituent'or'volatile oil'or'flavonoids'or'terpene'or'content',both in Chinese and English.According to the inclusion and exclusion criteria,the reported compositions and contents have been summarized,and SPSS software was used to draw the boxplot of contents.Results:A total of 603 natural compounds in 11 categories were obtained from pooled articles.In the diverse components,the number of aliphatic compounds(n=259)and terpenoids(n=158)are more than those of flavonoids(n=26),alkaloids(n=42)and aromatics(n=42).While,in the part of volatile oils of HCT,the largest components are aliphatic compounds(mainly distributed on the ground)and terpenoids(mainly distributed in the underground).Although,methyl n-nonylketone is distributed in the whole herb plant,a large proportion is present in the underground parts.As for non-volatiles,the flavonoid content(mainly distributed on the ground)was the highest,among which quercetin and its glycosyl derivatives were the prominent.Conclusion:The results of this study provide a more comprehensive material basis for the further study of HCT.It is also helpful to explain the mechanisms of anti-oxidant,anti-inflammatory,anti-bacterial,anti-viral and anti-cancer effects from the molecular target and molecular network levels. 展开更多
关键词 Houttuynia cordata Thunb INGREDIENT content Aliphatics TERPENOIDS FLAVONOIDS
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Digital twin driven and intelligence enabled content delivery in end-edge-cloud collaborative 5G networks
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作者 Bo Yi Jianhui Lv +2 位作者 Xingwei Wang Lianbo Ma Min Huang 《Digital Communications and Networks》 SCIE CSCD 2024年第2期328-336,共9页
The rapid development of 5G/6G and AI enables an environment of Internet of Everything(IoE)which can support millions of connected mobile devices and applications to operate smoothly at high speed and low delay.Howeve... The rapid development of 5G/6G and AI enables an environment of Internet of Everything(IoE)which can support millions of connected mobile devices and applications to operate smoothly at high speed and low delay.However,these massive devices will lead to explosive traffic growth,which in turn cause great burden for the data transmission and content delivery.This challenge can be eased by sinking some critical content from cloud to edge.In this case,how to determine the critical content,where to sink and how to access the content correctly and efficiently become new challenges.This work focuses on establishing a highly efficient content delivery framework in the IoE environment.In particular,the IoE environment is re-constructed as an end-edge-cloud collaborative system,in which the concept of digital twin is applied to promote the collaboration.Based on the digital asset obtained by digital twin from end users,a content popularity prediction scheme is firstly proposed to decide the critical content by using the Temporal Pattern Attention(TPA)enabled Long Short-Term Memory(LSTM)model.Then,the prediction results are input for the proposed caching scheme to decide where to sink the critical content by using the Reinforce Learning(RL)technology.Finally,a collaborative routing scheme is proposed to determine the way to access the content with the objective of minimizing overhead.The experimental results indicate that the proposed schemes outperform the state-of-the-art benchmarks in terms of the caching hit rate,the average throughput,the successful content delivery rate and the average routing overhead. 展开更多
关键词 Digital twin IoE content delivery CACHING Routing
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A glutathione S-transferase IbGSTL2 interacts with IbcPGM to increase starch content and improve starch quality in sweetpotato
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作者 Yue Fan Tianyu Chen +6 位作者 Luyao Xue Huan Zhang Shaopei Gao Ning Zhao Shaozhen He Hong Zhai Qingchang Liu 《The Crop Journal》 SCIE CSCD 2024年第6期1666-1676,共11页
A glutathione S-transferase(GST)gene IbGSTL2 was cloned and characterized from sweetpotato.It harbored a variation associated with starch content in storage roots.Overexpression of IbGSTL2 increased starch content and... A glutathione S-transferase(GST)gene IbGSTL2 was cloned and characterized from sweetpotato.It harbored a variation associated with starch content in storage roots.Overexpression of IbGSTL2 increased starch content and amylopectin proportion,decreased gelatinization temperature,and improved degree of crystallinity in sweetpotato storage roots,while its RNA interference resulted in the opposite trends.IbGSTL2 physically interacted with IbcPGM,an enzyme of sucrose metabolism,and improve starch content and quality by regulating genes involved in starch biosynthesis. 展开更多
关键词 IbcPGM IbGSTL2 Starch content Starch quality SWEETPOTATO
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Experimental and numerical analyses of the effect of fibre content on the close-in blast performance of a UHPFRC beam
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作者 Junbo Yan Qiyue Zhang +4 位作者 Yan Liu Yingliang Xu Zhenqing Shi Fan Bai Fenglei Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期242-261,共20页
Limited research has been conducted on the influences of fiber content on close-in blasting characteristics for ultrahigh-performance fiber-reinforced concrete(UHPFRC)beams.This paper aims to address this knowledge ga... Limited research has been conducted on the influences of fiber content on close-in blasting characteristics for ultrahigh-performance fiber-reinforced concrete(UHPFRC)beams.This paper aims to address this knowledge gap through experimental and mesoscale numerical methods.Experiments were conducted on ten UHPFRC beams built with varying steel fiber volumetric fractions subjected to close-in explosive conditions.Additionally,this study considered other parameters,such as the longitudinal reinforcement type and ratio.In the case of UHPFRC beams featuring normal-strength longitudinal reinforcement of diametersΦ12,Φ16,andΦ20,a reduction in maximum displacement by magnitudes of19.6%,19.5%,and 17.4%was observed,respectively,as the volumetric fractions of fiber increased from1.0%to 2.5%.In addition,increasing the longitudinal reinforcement ratio and using high-strength steel longitudinal reinforcement both significantly reduced the deformation characteristics and increase the blasting resistances of UHPFRC beams.However,the effects on the local crushing and spalling damage were not significant.A mesoscale finite element model,which considers the impacts of fiber parameters on UHPFRC beam behaviors,was also established and well correlated with the test findings.Nevertheless,parametric analyses were further conducted to examine the impacts of the steel fiber content and length and the hybrid effects of various types of microfibers and steel fibers on the blasting performance of UHPFRC beams. 展开更多
关键词 Blast performance Close-in blast Fiber content Mesoscale approach UHPFRC beams
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Selection and application of four QTLs for grain protein content in modern wheat cultivars
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作者 Zihui Liu Xiangjun Lai +4 位作者 Yijin Chen Peng Zhao Xiaoming Wang Wanquan Ji Shengbao Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2557-2570,共14页
The grain protein content(GPC)is the key parameter for wheat grain nutritional quality.This study conducted a resampling GWAS analysis using 406 wheat accessions across eight environments,and identified four previousl... The grain protein content(GPC)is the key parameter for wheat grain nutritional quality.This study conducted a resampling GWAS analysis using 406 wheat accessions across eight environments,and identified four previously reported GPC QTLs.An analysis of 87 landraces and 259 modern cultivars revealed the loss of superior GPC haplotypes,especially in Chinese cultivars.These haplotypes were preferentially adopted in different agroecological zones and had broad effects on wheat yield and agronomic traits.Most GPC QTLs did not significantly reduce yield,suggesting that high GPC can be achieved without a yield penalty.The results of this study provide a reference for future GPC breeding in wheat using the four identified QTLs. 展开更多
关键词 BREEDING grain protein content haplotype selection and application WHEAT
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Impact of Reservoir Heterogeneity on Bitumen Content in the Mackay River Oil Sands,Athabasca(Canada)
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作者 YANG Xiaofa YU Diyun +6 位作者 WU Suwei REN Junhao CHENG Dingsheng HUANG Jixin YANG Chengyu MA Guoqing LI Meijun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1285-1300,共16页
The Lower Cretaceous Manville Group of Upper Mc Murray Formation is one of the main bitumen reservoirs in Athabasca.In this study,the relationship between reservoirs heterogeneity and bitumen geochemical characteristi... The Lower Cretaceous Manville Group of Upper Mc Murray Formation is one of the main bitumen reservoirs in Athabasca.In this study,the relationship between reservoirs heterogeneity and bitumen geochemical characteristics were analyzed through core and microscopic observation,lab analysis,petrophysics and logging data.Based on the sedimentology framework,the formation environment of high-quality oil sand reservoirs and their significance for development were discussed.The results indicate that four types lithofacies were recognized in the Upper Mc Murray Formation based on their depositional characteristics.Each lithofacies reservoirs has unique physical properties,and is subject to varying degrees of degradation,resulting in diversity of bitumen content and geochemical composition.The tidal bar(TB)or tidal channel(TC)facies reservoir have excellent physical properties,which are evaluated as gas or water intervals due to strong degradation.The reservoir of sand bar(SB)facies was evaluated as oil intervals,due to its poor physical properties and weak degradation.The reservoir of mixed flat(MF)facies is composed of sand intercalated with laminated shale,which is evaluated as poor oil intervals due to its poor connectivity.The shale content in oil sand reservoir is very important for the reservoir physical properties and bitumen degradation degree.In the context of regional biodegradation,oil sand reservoirs with good physical properties will suffer from strong degradation,while oil sand reservoirs with relatively poor physical properties are more conducive to the bitumen preservation. 展开更多
关键词 oil sands reservoir heterogeneity geochemical characteristics bitumen content Upper Mc Murray Formation CANADA
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Can soil remediation agents synergistically mitigate rice Cd content and CH_(4)emission from karst paddies?
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作者 Wangbiao Lu Guangneng Zeng +8 位作者 Weijun Luo Jiangju Song Maofei Ni Shuangqin Guo Qi Zhang Chengling Huang Cheng Yang Haijun Du Shijie Wang 《Acta Geochimica》 EI CAS CSCD 2024年第6期1123-1132,共10页
Rice(Oryza sativa L.)paddies are increasingly threatened by cadmium(Cd)pollution,and potentially serve as CH_(4)emitters to the atmosphere.Remediation agents widely mitigate Cd pollution in paddy soil,however,we know ... Rice(Oryza sativa L.)paddies are increasingly threatened by cadmium(Cd)pollution,and potentially serve as CH_(4)emitters to the atmosphere.Remediation agents widely mitigate Cd pollution in paddy soil,however,we know little about their regulations on CH_(4)emission.Here,via adding biochar(B),sulfhydryl-modified palygorskite(SMP),and selenium foliar fertilizer(SFF),we conducted a pot experiment to investigate soil and rice Cd contents together with in-situ CH_(4)f luxes.Compared to CK,the addition of SMP,SFF,and B-SMP reduced Cd in brown rice by 25%to 50%,25%,and 50%to 75%,respectively.Agents 7%B,7%B-0.01%SMP,and SFF reduced CH_(4)emissions by 8.46%,5.30%,and 4.11%,respectively.CH_(4)emission increased gradually along the growing season,with the cumulative CH_(4)fluxes ranging between 338.82 and 619.13 kg hm^(-2).Our results highlight that mixed 7%B-0.01%SMP and SFF showed collaborative eff ects on Cd remediation and CH_(4)emission.This study reveals the feasibility of reducing Cd pollution and CH_(4)emission in karst rice paddies,which hopes to supplement the knowledge of collaborative controls on soil remediation and carbon emission. 展开更多
关键词 Cd content CH_(4) FLUX Remediation agents Synergistical effect Rice paddy
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Effect of phosphorus content on interfacial heat transfer and film deposition behavior during the high-temperature simulation of strip casting
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作者 Wanlin Wang Cheng Lu +5 位作者 Liang Hao Jie Zeng Lejun Zhou Xinyuan Liu Xia Li Chenyang Zhu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1016-1025,共10页
The interfacial wettability and heat transfer behavior are crucial in the strip casting of high phosphorus-containing steel.A hightemperature simulation of strip casting was conducted using the droplet solidification ... The interfacial wettability and heat transfer behavior are crucial in the strip casting of high phosphorus-containing steel.A hightemperature simulation of strip casting was conducted using the droplet solidification technique with the aims to reveal the effects of phosphorus content on interfacial wettability,deposited film,and interfacial heat transfer behavior.Results showed that when the phosphorus content increased from 0.014wt%to 0.406wt%,the mushy zone enlarged,the complete solidification temperature delayed from1518.3 to 1459.4℃,the final contact angle decreased from 118.4°to 102.8°,indicating improved interfacial contact,and the maximum heat flux increased from 6.9 to 9.2 MW/m2.Increasing the phosphorus content from 0.081wt%to 0.406wt%also accelerated the film deposition rate from 1.57 to 1.73μm per test,resulting in a thickened naturally deposited film with increased thermal resistance that advanced the transition point of heat transfer from the fifth experiment to the third experiment. 展开更多
关键词 strip casting interfacial heat transfer interfacial wettability naturally deposited film phosphorus content
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Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China
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作者 Gang Li Xian-Ming Xiao +3 位作者 Bo-Wei Cheng Chen-Gang Lu Yue Feng Dong-Sheng Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1488-1507,共20页
The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not w... The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not well understood.In the present study,two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area,representing the deep-water shelf facies and shallowwater platform facies,respectively,were investigated on the differences of pore types,pore structure and methane adsorption capacity between them,and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were discussed.The results show that the organic matter(OM)pores in the YD4 shale samples are dominant,while the inorganic mineral(IM)pores in the YD5 shale samples are primary,with underdeveloped OM pores.The pore specific surface area(SSA)and pore volume(PV)of the YD4 shale samples are mainly from micropores and mesopores,respectively,while those of the YD5 shale samples are mainly from micropores and macropores,respectively.The methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples,with a maximum absolute adsorption capacity of 3.13 cm^(3)/g and 1.31 cm^(3)/g in average,respectively.Compared with the shallow-water platform shale,the deep-water shelf shale has a higher TOC content,a better kerogen type and more developed OM pores,which is the main mechanism for its higher adsorption capacity.The GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 34 m^(3)/t within a depth range of 1000—4000 m,with shale gas exploration and development potential,while the shallow-water platform shale has normally a GIP content of<1 m^(3)/t,with little shale gas potential.Considering the geological and geochemical conditions of shale gas formation and preservation,the deep-water shelf facies is the most favorable target for the Lower Cambrian shale gas exploration and development in the western Hubei area,South China. 展开更多
关键词 Lower Cambrian shale Deep-water shelf facies Shallow-waterplat form facies Pore structure Methane adsorption Gas-in-place content Controlling factor
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Predictability of the upper ocean heat content in a Community Earth System Model ensemble prediction system
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作者 Ting Liu Wenxiu Zhong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第1期1-10,共10页
Upper ocean heat content(OHC)has been widely recognized as a crucial precursor to high-impact climate variability,especially for that being indispensable to the long-term memory of the ocean.Assessing the predictabili... Upper ocean heat content(OHC)has been widely recognized as a crucial precursor to high-impact climate variability,especially for that being indispensable to the long-term memory of the ocean.Assessing the predictability of OHC using state-of-the-art climate models is invaluable for improving and advancing climate forecasts.Recently developed retrospective forecast experiments,based on a Community Earth System Model ensemble prediction system,offer a great opportunity to comprehensively explore OHC predictability.Our results indicate that the skill of actual OHC predictions varies across different oceans and diminishes as the lead time of prediction extends.The spatial distribution of the actual prediction skill closely resembles the corresponding persistence skill,indicating that the persistence of OHC serves as the primary predictive signal for its predictability.The decline in actual prediction skill is more pronounced in the Indian and Atlantic oceans than in the Pacific Ocean,particularly within tropical regions.Additionally,notable seasonal variations in the actual prediction skills across different oceans align well with the phase-locking features of OHC variability.The potential predictability of OHC generally surpasses the actual prediction skill at all lead times,highlighting significant room for improvement in current OHC predictions,especially for the North Indian Ocean and the Atlantic Ocean.Achieving such improvements necessitates a collaborative effort to enhance the quality of ocean observations,develop effective data assimilation methods,and reduce model bias. 展开更多
关键词 ocean heat content prediction skill retrospective forecast experiment
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Estimation of unfrozen water content of saturated sandstones using nuclear magnetic resonance, mercury intrusion porosimetry, and ultrasonic tests
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作者 Fei Liu Shibing Huang +1 位作者 Gang Liu Shilin Yu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3465-3484,共20页
The unfrozenwater content(UWC)is a crucial parameter that affects the strength and thermal properties of rocks in relation to engineering construction and geological disasters in cold regions.In this study,three diffe... The unfrozenwater content(UWC)is a crucial parameter that affects the strength and thermal properties of rocks in relation to engineering construction and geological disasters in cold regions.In this study,three different methods were employed to test and estimate the UWC of saturated sandstones,including nuclear magnetic resonance(NMR),mercury intrusion porosimetry(MIP),and ultrasonic methods.The NMR method enabled the direct measurement of the UWC of sandstones using the free induction decay(FID).The MIP method was used to analyze the pore structures of sandstones,with the UWC subsequently calculated based on pore ice crystallization.Therefore,the MIP test constituted an indirect measurement method.Furthermore,a correlation was established between the P-wave velocity and the UWC of these sandstones based on the mixture theory,which could be employed to estimate the UWC as an empirical method.All methods demonstrated that the UWC initially exhibited a rapid decrease from 0C to5C and then generally became constant beyond20C.However,these test methods had different characteristics.The NMR method was used to directly and accurately calculate the UWC in the laboratory.However,the cost and complexity of NMR equipment have precluded its use in the field.The UWC can be effectively estimated by the MIP test,but the estimation accuracy is influenced by the ice crystallization process and the pore size distribution.The P-wave velocity has been demonstrated to be a straightforward and practical empirical parameter and was utilized to estimate the UWC based on the mixture theory.This method may be more suitable in the field.All methods confirmed the existence of a hysteresis phenomenon in the freezing-thawing process.The average hysteresis coefficient was approximately 0.538,thus validating the GibbseThomson equation.This study not only presents alternative methodologies for estimating the UWC of saturated sandstones but also contribute to our understanding of the freezing-thawing process of pore water. 展开更多
关键词 Unfrozen water content(UWC) Nuclear magnetic resonance(NMR) Mercury intrusion porosimetry(MIP) Pore structures P-wave velocity SandSTONE
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Effects of the Dicranopteris linearis root system and initial moisture content on the soil disintegration characteristics of gully erosion 被引量:2
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作者 HE Ling DENG Yu-Song +3 位作者 TANG Qiu-yue LIAO Da-lan WANG Chao DUAN Xiao-qian 《Journal of Mountain Science》 SCIE CSCD 2022年第12期3548-3567,共20页
Benggang erosion is caused by a special type of gully erosion in southern China that seriously endangers the local ecology and environment.In this study,typical Benggang collapsing-wall soils were used as the study ar... Benggang erosion is caused by a special type of gully erosion in southern China that seriously endangers the local ecology and environment.In this study,typical Benggang collapsing-wall soils were used as the study area to investigate the effects of different initial moisture contents and dicranopteris linearis root weight densities,as well as their interactions on disintegration in orthogonal test method.The results showed that the rate of soil disintegration decreased as a linear function of the initial moisture content.The soil disintegration rate tended to rise and then fall as the root weight density increased,reflecting an optimum root weight density of 0.75-1.00 g/100 cm3.The incorporation of dicranopteris linearis roots was most effective for soil consolidation in the shallow layers of soil.In addition,the disintegration rate of the collapsing-wall soils increases as the soil layer deepened.The dicranopteris linearis root system and initial moisture content had an interactive effect that was more pronounced in deeper soils.However,the combined effect of these processes was always dominated by the initial moisture content.Moderate initial soil moisture content(0.20-0.24 g/g)and the addition of a high root density in dicranopteris linearis(0.75-1.00 g/100 cm3)were the optimal combinations that reduced the disintegration rate.In conclusion,maintaining a suitable natural moisture content in collapsing-wall soils and taking measures that use plants to consolidate soil can effectively prevent and control the occurrence of Benggang erosion.The results of this study provided further insight into the factors that influence soil disintegration and offered a scientific basis for soil erosion management in the southern China. 展开更多
关键词 Collapsing wall Initial moisture content Interactive effect Root weight density Soil disintegration
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Observations and Modeling of Ice Water Content in a Mixed-Phase Cloud System 被引量:2
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作者 HOU Tuan-Jie LEI Heng-Chi +1 位作者 HU Zhao-Xia FENG Qiu-Juan 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第4期210-215,共6页
The ice water content(IWC) distribution in a mixed-phase cloud system was investigated using Cloud-Sat data,aircraft measurements,and the Weather Research and Forecasting(WRF) model.Simulated precipitation and IWC wer... The ice water content(IWC) distribution in a mixed-phase cloud system was investigated using Cloud-Sat data,aircraft measurements,and the Weather Research and Forecasting(WRF) model.Simulated precipitation and IWC were in general agreement with rain gauge,sat-ellite,and aircraft observations.The cloud case was char-acterized by a predominant cold layer and high IWC throughout the cloud-development and precipitation stages.The CloudSat-retrieved products suggested that the IWC was distributed from 4.0 to 8.0 km,with the maximum values(up to 0.5 g m-3) at 5.0-6.0 km at the earlymature stage of cloud development.High IWC(up to 0.8 g m-3) was also detected by airborne probes at 4.2 and 3.6 km at the late-mature stage.The WRF model simulation re-vealed that the predominant riming facilitated rapid ac-cumulation of high IWC at 3.0-6.0 km. 展开更多
关键词 aircraft observation ice water content WRF
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Influence of wind-blown sand content on the mechanical quality state of ballast bed in sandy railways
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作者 Yihao Chi Hong Xiao +3 位作者 Zhihai Zhang Yang Wang Zhongxia Qian Weize Zhao 《Railway Engineering Science》 EI 2024年第4期533-550,共18页
During the operation of sandy railways, the challenge posed by wind-blown sand is a persistent issue. An in-depth study on the influence of wind-blown sand content on the macroscopic and microscopic mechanical propert... During the operation of sandy railways, the challenge posed by wind-blown sand is a persistent issue. An in-depth study on the influence of wind-blown sand content on the macroscopic and microscopic mechanical properties of the ballast bed is of great significance for understanding the potential problems of sandy railways and proposing reasonable and adequate maintenance and repair strategies. Building upon existing research, this study proposes a new assessment indicator for sand content. Utilizing the discrete element method(DEM) and fully considering the complex interactions between ballast and sand particles, three-dimensional(3D) multi-scale analysis models of sandy ballast beds with different wind-blown sand contents are established and validated through field experiments. The effects of varying wind-blown sand content on the microscopic contact distribution and macroscopic mechanical behavior(such as resistance and support stiffness) of ballast beds are carefully analyzed. The results show that with the increase in sand content, the average contact force and coordination number between ballast particles gradually decrease, and the disparity in contact forces between different layers of the ballast bed diminishes. The longitudinal and lateral resistance of the ballast bed initially decreases and then increases, with a critical point at 10% sand content. At 15% sand content, the lateral resistance is mainly shared by the ballast shoulder. The longitudinal resistance sharing ratio is always the largest on the sleeper side, followed by that at the sleeper bottom, and the smallest on the ballast shoulder. When the sand content exceeds 10%, the contribution of sand particles to stiffness significantly increases, leading to an accelerated growth rate of the overall support stiffness of the ballast bed, which is highly detrimental to the long-term service performance of the ballast bed. In conclusion, it is recommended that maintenance and repair operations should be promptly conducted when the sand content of the ballast bed reaches or exceeds 10%. 展开更多
关键词 Sandy railway Wind-blown sand content Discrete element method(DEM) Macroscopic and microscopic mechanical properties Maintenance and repair strategies
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Effect of V content on microstructures and properties of TiC cermet fusion welding interface
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作者 魏炜 徐莹 +2 位作者 王旭 黄智泉 刘胜新 《China Welding》 CAS 2024年第1期40-45,共6页
The effects of vanadium(V)on the microstructures and mechanical properties of the TiC cermet fusion welding interface were studied by adjusting the content of V in the self-developed flux-cored wires using metal inert... The effects of vanadium(V)on the microstructures and mechanical properties of the TiC cermet fusion welding interface were studied by adjusting the content of V in the self-developed flux-cored wires using metal inert gas arc(MIG)welding for surfacing on the TiC cermet.The results show that the increase in V content promotes the element diffusion between TiC cermet and weld metal.There are no de-fects observed in the interface,and the diffusion of elements refers to excellent metallurgical bonding.The shear strength of the fusion zone initially decreases and then increases with the increase in V content.The maximum shear strength of the TiC cermet/weld interface,reaching 552 MPa,occurred when the V content reached 0.65%.Meanwhile,the average hardness in the transition zone reached 488.2 HV0.2. 展开更多
关键词 TiC cermet MIG welding INTERFACE V content shear strength
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Research Progress on Purification Process, Content Determination and Pharmacological Action of Atractylodin
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作者 Xin SUN Jingwen WANG +1 位作者 Yang XI Chenghao JIN 《Asian Agricultural Research》 2024年第3期33-35,40,共4页
Atractylodis Rhizoma comes from the dry rhizome of Atractylis lancea or Atractylodes chinensis in the Compositae family,and it is suitable for preventing and treating diseases such as cold,edema,night blindness and rh... Atractylodis Rhizoma comes from the dry rhizome of Atractylis lancea or Atractylodes chinensis in the Compositae family,and it is suitable for preventing and treating diseases such as cold,edema,night blindness and rheumatic arthralgia.Atractylodin is the main active component extracted and isolated from Atractylodis Rhizoma.A large number of studies have found that atractylodin has excellent drug activity in improving gastrointestinal emptying,anti-inflammation,inhibiting malignant tumor and reducing blood lipid.In this paper,the purification process and pharmacological activity of Atractylodin were summarized to provide a theoretical basis for basic research,clinical application and further development and utilization of atractylodin. 展开更多
关键词 ATRACTYLODIN PHARMACOLOGICAL action PURIFICATION PROCESS content DETERMINATION
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TLC Identification of Yao Medicine Pileostegia tomentellal and Extraction Technology and Content Determination of Umbelliferone
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作者 Jiangcun WEI Xiumei MA +5 位作者 Meiyan QIU Bing QING Jingrong LU Hong LEI Xiaodong HUANG Wen ZHONG 《Medicinal Plant》 2024年第2期15-17,20,共4页
[Objectives]To establish a TLC and content determination method of Pileostegia tomentellal,with umbelliferone as the indicator component.[Methods]TLC identification was performed by silica gel G thin layer plate with ... [Objectives]To establish a TLC and content determination method of Pileostegia tomentellal,with umbelliferone as the indicator component.[Methods]TLC identification was performed by silica gel G thin layer plate with n-hexane-ethyl acetate(4:3)as the developing agent,and the plate was examined by UV lamp(365 nm).The umbelliferone content was determined by HPLC:Inertsil ODS-3 C 18 column(4.60 mm×250 mm,5μm);mobile phase acetonitrile-0.2%phosphoric acid gradient elution;detection wavelength 320 nm,flow rate 1.0 mL/min,column temperature 30℃,injection volume 10μL.[Results]The chromatogram of P.tomentellal showed the same color spot in the same position as that of reference medicinal material,and the spot was clear with good specificity.Umbelliferone showed a good linear relationship when the injection volume was 2.63-131.27μg/mL(R^(2)=0.9997).The average recovery of umbelliferone in the low,middle and high adding groups of P.tomentellal was 99.57%and the RSD was 2.15%.[Conclusions]The method can effectively identify Yao medicine P.tomentellal and accurately determine the content of umbelliferone in medicinal materials,which will provide a scientific basis for the development and utilization of medicinal resources of Yao medicine P.tomentellal. 展开更多
关键词 Pileostegia tomentellal TLC identification Extraction technology UMBELLIFERONE content determination
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