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Designing laser powder bed fusion low-alloyed titanium with superior strength-ductility trade-offvia machine learning
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作者 Xiaohang Zhang Xing Ran +7 位作者 Zhe Wang Wei Xu Xiangyu Zhu zhiheng du Jiazhen Zhang Runguang Li Yageng Li Xin Lu 《Journal of Materials Science & Technology》 2025年第34期323-330,共8页
1.Introduction Titanium(Ti)and its alloy have become a critical structural material in aerospace,weaponry,and equipment industries due to their high strength,low density,and excellent corrosion resistance[1-3].
关键词 machine learning weaponry high strength structural material aerospace strength ductility trade off laser powder bed fusion equipment industries
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CH_(4) and CO_(2) emissions and dissolved carbon exporting in rivers on the upper Lanzhou section of the Yellow River,China
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作者 zhiheng du Hao Cui +11 位作者 Fangping Yan Lei Wang Zhiqiang Wei Wenhan Hu Simin Xie Changlian Tao Qian Xu Qiangqiang Xu Yicheng Wang Jingfeng Liu Xiaoxiang Wang Minzhu He 《Geoscience Frontiers》 2025年第4期153-167,共15页
The Yellow River(YR),China’s second-longest river,remains understudied regarding its greenhouse gases(GHGs)emissions,particularly the impacts of urban drainage ditches and wastewater treatment facilities on regional ... The Yellow River(YR),China’s second-longest river,remains understudied regarding its greenhouse gases(GHGs)emissions,particularly the impacts of urban drainage ditches and wastewater treatment facilities on regional GHGs dynamics.This study investigated methane(CH_(4))and carbon dioxide(CO_(2))concentrations,fluxes and stable carbon isotopes(δ^(13)C-CH_(4)and δ^(13)C-CO_(2))across six main stream,three ditches,and one wastewater treatment site along the upper Lanzhou section of the YR,spanning from the urban entrance(36.176°N,103.449°E)to the exit of Lanzhou city(36.056°N,104.020°E).Measured CH_(4)diffusion fluxes in mainstem sites ranged from 0.01 to 2.58 mmol·m^(−2)·d^(−1)(mean:0.36 mmol·m^(−2)·d^(−1)),while ebullitive fluxes(gas bubbles)ranged from 0.01 to 18.89 mmol·m^(−2)·d^(−1)(mean:0.90 mmol·m^(−2)·d^(−1)).CO_(2)diffusion fluxes varied between 9.16–92.80 mmol·m^(−2)·d^(−1)(averaged:39.11 mmol·m^(−2)·d^(−1))at these locations.Ebullition(bubble)fluxes accounted for 53.1%±22.4%(range:9.0%to 98.4%)to total CH_(4)emissions(diffusion plus ebullition),with peak fluxes occurring during summer,indicating its significance as a CH_(4)transport mechanism.Notably,both diffusion CH_(4)and CO_(2)fluxes and ebullitive CH_(4)rates at ditch sites substantially exceeded those in mainstream reaches.The lowest CH_(4)and highest CO_(2)concentrations were observed at a wastewater treatment site,likely resulting from the removal of high organic loads.Acetoclastic methanogenesis—the process converting acetate-derived methyl groups to CH_(4)—was identified as the dominant production pathway in both mainstream and ditch environments.CH_(4)and CO_(2)flux magnitudes in the upper YR(Lanzhou section)were comparable to those observed in subtropical Yangtze River tributaries.These results demonstrate that anthropogenic influences significantly enhance CO_(2)/CH_(4)emissions,and the lateral exports of dissolved carbon(DIC and DOC)in the main stream site was quantified.,which cannot be overlooked.The findings emphasize the critical need to account for pronounced spatiotemporal variations in arid-region GHG fluxes to improve basin-scale estimates for the YR. 展开更多
关键词 Yellow River CH_(4)and CO_(2)fluxes δ^(13)C isotope Ditch and Wastewater treatment water Acetoclastic methanogenesis
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A Statistical Linkage between Extreme Cold Wave Events in Southern China and Sea Ice Extent in the Barents-Kara Seas from 1289 to 2017 被引量:4
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作者 Cunde XIAO Qi ZHANG +4 位作者 Jiao YANG zhiheng du Minghu DING Tingfeng DOU Binhe LUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第12期2154-2168,共15页
Arctic sea ice loss and the associated enhanced warming has been related to midlatitude weather and climate changes through modulate meridional temperature gradients linked to circulation. However, contrasting lines o... Arctic sea ice loss and the associated enhanced warming has been related to midlatitude weather and climate changes through modulate meridional temperature gradients linked to circulation. However, contrasting lines of evidence result in low confidence in the influence of Arctic warming on midlatitude climate. This study examines the additional perspectives that palaeoclimate evidence provides on the decadal relationship between autumn sea ice extent (SIE) in the Barents-Kara (B-K) Seas and extreme cold wave events (ECWEs) in southern China. Reconstruction of the winter Cold Index and SIE in the B-K Seas from 1289 to 2017 shows that a significant anti-phase relationship occurred during most periods of decreasing SIE, indicating that cold winters are more likely in low SIE years due to the “bridge” role of the North Atlantic Oscillation and Siberian High. It is confirmed that the recent increase in ECWEs in southern China is closely related to the sea ice decline in the B-K Seas. However, our results show that the linkage is unstable, especially in high SIE periods, and it is probably modulated by atmospheric internal variability. 展开更多
关键词 extreme cold wave events sea ice Barents-Kara(B-K)Seas Arctic southern China
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Accumulation and geochemical evidence for the Little Ice Age episode in eastern Antarctica 被引量:1
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作者 ChuanJin Li JiaWen Ren +5 位作者 CunDe Xiao MingHu Ding AiHong Xie zhiheng du XiangYu Ma DaHe Qin 《Research in Cold and Arid Regions》 CSCD 2019年第1期50-61,共12页
Data on accumulation and concentration of chemical compounds recorded in an essentially unexplored area(Dome Argus)of the Indian Ocean sector of eastern Antarctica during the past 2,680 years(680 B.C. to 1999 A.D.) ar... Data on accumulation and concentration of chemical compounds recorded in an essentially unexplored area(Dome Argus)of the Indian Ocean sector of eastern Antarctica during the past 2,680 years(680 B.C. to 1999 A.D.) are presented. During the first 1, 700 years(680 B. C. to 1000 A. D.), the accumulation data shows a slightly decreasing trend, while chemical ions appear to be stable, representing a stable climatic condition. An intensive increasing trend of the accumulation occurred during the 12^(th) to 14^(th) century. The period from 15^(th) to 19^(th) century was characterized by a rapid reducing accumulation and concentrations of volatile compounds suffering post-depositional loss linked to sparse precipitation amount,which was temporally consistent with the Little Ice Age(LIA) episode. Comparison between observed accumulation rates with other eastern Antarctic ice cores show a consistent decreasing trend during LIA, while sea salt and dust-originated ions increased due to sea ice extent and intensified atmospheric transportation. Distribution of volcanic originated sulfate over the Antarctic continent show a significant change during the 15^(th) century, coincident with the onset of the LIA. These results are important for the assessment of Antarctic continent mass balance and associated interpretation of the Dome A deep ice core records. 展开更多
关键词 ACCUMULATION rates sea SALT chemical compounds LITTLE Ice Age EASTERN ANTARCTICA
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Pattern self-referenced single-pixel computational holographic imaging 被引量:1
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作者 Wenjing Zhao Zefang Gao +2 位作者 zhiheng du Aiping Zhai Dong Wang 《Advanced Photonics Nexus》 2024年第5期102-109,共8页
We propose pattern self-referenced single-pixel common-path holography(PSSCH),which can be realized using either the digital-micromirror-device(DMD)based off-axis scheme or the DMD-based phaseshifting approach,sharing... We propose pattern self-referenced single-pixel common-path holography(PSSCH),which can be realized using either the digital-micromirror-device(DMD)based off-axis scheme or the DMD-based phaseshifting approach,sharing the same experimental setup,to do wavefront reconstructions.In this method,each modulation pattern is elaborately encoded to be utilized to not only sample the target wavefront but also to dynamically introduce the reference light for single-pixel common-path holographic detection.As such,it does not need to intentionally introduce a static reference light,resulting in it making full use of the pixel resolution of the modulation patterns and suppressing dynamically varying noises.Experimental demonstrations show that the proposed method can not only obtain a larger field of view than the peripheral-referenced approach but also achieve a higher imaging resolution than the checkerboardreferenced approach.The phase-shifting-based PSSCH performs better than the off-axis-based PSSCH on imaging fidelity,while the imaging speed of the latter is several times faster.Further,we demonstrate our method to do wavefront imaging of a biological sample as well as to do phase detection of a physical lens.The experimental results suggest its effectiveness in applications. 展开更多
关键词 single-pixel imaging wavefront reconstruction self-referenced off-axis interferometry phase-shifting interferometry
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Isolation and Characterization of 15 Microsatellite DNA Loci for the Alpine Stream Frog Scutiger boulengeri (Anura: Megophryidae)
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作者 zhiheng du Chunzhu XU Fangyong NING 《Asian Herpetological Research》 SCIE CSCD 2016年第4期298-300,共3页
Fifteen microsatellite DNA markers were developed from a transcriptome assembly of the alpine stream frog (Scutiger boulengeri).To characterize these loci, we genotyped 23 individuals collected from two sites. Eleve... Fifteen microsatellite DNA markers were developed from a transcriptome assembly of the alpine stream frog (Scutiger boulengeri).To characterize these loci, we genotyped 23 individuals collected from two sites. Eleven loci were variable, with the number of alleles ranging from one to six within each population. The expected and observed heterozygosities ranged from 0 to 0.78 and from 0 to 0.64, respectively. None of the loci was in linkage disequilibrium and one locus for one population was deviated from will offer useful tools in detecting population structure Tibetan Plateau, where the species resides. the Hardy-Weinberg equilibrium. We hope that these markers of S. boulengeri and in monitoring the fragile ecosystem of the 展开更多
关键词 Alpine stream frogs Microsatellite DNA Tibetan Plateau Scutiger boulengeri
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Observed features of stable surface seawater isotopes across the Pacific, Indian and Southern oceans
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作者 Xuemei Wu Weijun Sun +3 位作者 Biao Tian Baojuan Huai zhiheng du Minghu Ding 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第10期33-39,共7页
The marine hydrological process is still unclear due to scarce observations.Based on stable water isotopes in surface seawater along the 33rd Chinese National Antarctic Science Expedition from November 2016 to April 2... The marine hydrological process is still unclear due to scarce observations.Based on stable water isotopes in surface seawater along the 33rd Chinese National Antarctic Science Expedition from November 2016 to April 2017,this study explored the hydrological processes in the Pacific,Indian and Southern oceans.The results show that the Northwest Pacific(0°–26°N)is a region with strong evaporation(theδ18O-δD slope is 6.58),while the southern Indian Ocean is a region with strong precipitation(theδ18O-δD slope is 9.57).The influence of continental runoff and water mass mixing reduces the correlation betweenδ18O and salinity in the eastern Indian Ocean.The characteristics of the isotopes and hydrological parameters indicate that the Agulhas Front and sub-Tropical Convergence do not merge in the Antarctic–Indian Ocean region.The freezing of sea ice near the Antarctic continent decreases theδ18O andδD by 0.40‰and 7.0‰,respectively,compared with those near 67°S.This study is helpful for understanding marine hydrological processes and promoting the understanding and research of the nature of ocean responses in the context of climate change. 展开更多
关键词 spatial variability surface seawater isotopes δ18O-salinity relation water mass fronts
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Sources, evolution and impacts of EC and OC in snow on sea ice: a measurement study in Barrow, Alaska 被引量:8
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作者 Tingfeng Dou Cunde Xiao +7 位作者 zhiheng du J. J. Schauer Hong Ren Baozhu Ge Aihong Xie Jihua Tan Pingqing Fu Yuanxun Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2017年第22期1547-1554,共8页
Based on the field measurements in Barrow, Alaska within the period of April-May 2015, we investigate the sources and variations of elemental carbon(EC) and organic carbon(OC) in the surface layer of snowpack on sea i... Based on the field measurements in Barrow, Alaska within the period of April-May 2015, we investigate the sources and variations of elemental carbon(EC) and organic carbon(OC) in the surface layer of snowpack on sea ice, and estimate their effects on the sea ice albedo. Results show that the snow OC in Barrow are from natural sources(e.g. terrestrial higher plants and micro-organisms) mainly, as well as biomass burning(e.g. forest fires and straw combustion) as an important part. Both EC and OC can accumulate at the snow surface with snow melt. The variations in EC and OC and liquid water content in the snow layer are well consistent during the snow-melting period. A higher rate of snow melt implied a more efficient enrichment of EC and OC. In the last phase of snow melt, the concentration increased to a maximum of 16.2 ng/g for EC and 128 ng/g for OC, which is ~10 times larger than those before snow melt onset. Except for the dominant influence of melt amplification mechanism, the variation in concentrations of EC and OC could be disturbed by the air temperature fluctuation and snowfall. Our study indicates that the lightabsorbing impurities contributed 1.6%-5.1% to the reduction in sea ice albedo with melt during the measurement period. The significant period oflight-absorbing impurities influencing on sea ice albedo begins with the rapid melting of overlying snow and ends before the melt ponds formed widely, which lasted for about 10 days in Barrow, 2015. 展开更多
关键词 ARCTIC EC OC Sea ice ALBEDO BARROW
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Temperate ice layer found in the upper area of Jima Yangzong Glacier,the headstream of Yarlung Zangbo River 被引量:1
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作者 Tong Zhang Minghu Ding +2 位作者 Cunde Xiao Dongqi Zhang zhiheng du 《Science Bulletin》 SCIE EI CAS CSCD 2016年第8期619-621,共3页
For the first time we investigate the basal thermal condition in the upper area of Jima Yangzong Glacier, the headstream of Yarlung Zangbo River, using ground-penetrating radar techniques. With common offset and commo... For the first time we investigate the basal thermal condition in the upper area of Jima Yangzong Glacier, the headstream of Yarlung Zangbo River, using ground-penetrating radar techniques. With common offset and common mid-point surveys we analyze the radar velocities in ice with respect to cold-temperate ice transi- tion surface (0.1751 0.0028 m ns-~) and ice-bedrock interface (0.1657 + 0.0033 m ns-a), indicating a radar velocity of 0.1410 4- 0.0154 m ns-1 for the temperate ice layer (16.6 ~ 1.8 m). We estimate that the temperate ice layer has a water content of around 6 % 4- 4 %, suggesting that the Jima Yangzong Glacier, previously known as continental-type, now possibly becomes polythermal. 展开更多
关键词 Jima Yangzong Glacier YarlungZangbo River - Ground-penetrating radar Radarvelocity - Englacial water content Polythermal
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Male heterogametic sex determination in Rana dybowskii based on sex-linked molecular markers
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作者 Yuan XU zhiheng du +8 位作者 Jiayu LIU Hang SU Fangyong NING Shiquan CUI Lijuan WANG Jianming LIU Chuanshuai REN Shengwei DI Xiujuan BAI 《Integrative Zoology》 SCIE CSCD 2022年第1期105-114,共10页
Identifying the mechanism for sex determination in amphibians is challenging.Very little is known about sex determination mechanisms of Rana dybowskii,a species of importance to evolutionary and conservation biology.W... Identifying the mechanism for sex determination in amphibians is challenging.Very little is known about sex determination mechanisms of Rana dybowskii,a species of importance to evolutionary and conservation biology.We screened for sex-linked molecular markers in R.dybowskii in China using target region amplification polymorphism with 2 fixed primers against the sequences of Dmrt1.We found 2 male-linked molecular markers in R.dybowskii,which were 222 bp and 261 bp long.The detection rates of 222 bp marker in males form Xinglong,Huadian,and Dandong were 93.79%,69.64%,and 13.64%,respectively,while the rate in females from Huadian was 27.50%.Besides,the detection rates of 261 bp marker in the above 3 regions were only observed in males at the rate of 93.79%,87.50%,and 32.73%,respectively.The inheritance patterns of sex-linked molecular markers showed that the 2 sex-linked molecular markers were heterozygous.Compared to the XY-male parent,progeny from XX-pseudo-male parent possessed lower sex reversal ratio at the same rearing temperature,and the proportion of female froglets from an XX-pseudo-male parent was more than 95%at low rearing temperature(15°C).Our findings suggest that R.dybowskii displays male heterogamety,and the 2 sex-linked molecular markers may have a guiding significance for the protection and utilization of R.dybowskii. 展开更多
关键词 male-linked molecular markers Rana dybowskii sexual reversal TRAP markers
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