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Thermal stability of permafrost under U-shaped crushed rock embankment of the qinghai-Tibet Railway

Advances in Climate Change Research 2024年第1期15卷 158-169页

作者： Kun-Ming XU Guan-Li JIANG Ji CHEN qing-Bai wu State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Beiluhe Observation Station of Frozen Soil Environment and Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China

The U-shaped crushed rock embankment(UCRE),of which widely utilized in the permafrost regions along the qinghai-Tibet Railway,has the capability to rapidly reduce the ground temperature of the underlying ***,there remains uncertainty regarding the adaptation of UCRE to climate change and its long-term cooling *** study focuses on nine UCRE monitoring sites along the qinghai-Tibet Railway to analyze the dynamic variations of the ground temperature underlying permafrost from 2006 to *** efficiency of UCRE in stabilizing permafrost temperature in different permafrost zones is evaluated by considering the permafrost table,ground temperature,and MAGT,as well as the temperature difference between the top and bottom of the crushed rock layer and the ground temperature variation index(GTVI).The results show that UCRE is suitable for application in extremely unstable warm permafrost regions where the MAGT is higher than-0.5℃.Moreover,UCRE effectively diminishes the disparity in permafrost thermal stability between the sunny and shaded shoulders of the *** short-term and long-term effect of cooling permafrost is experiencing a change related with permafrost ***,in stable cold permafrost regions with MAGT lower than-1.5℃,the long-term cooling effect of UCRE on permafrost seems to gradually di-minishes,but UCRE continues to fulfill the role of stabilizing the underlying permafrost thermal state over the *** results show that UCRE can quickly restore and stabilize the thermal state of permafrost in the early stages of construction,and adapt to the influence of future climate *** findings provide important guidance for understanding the variations of permafrost thermal stability beneath the embankment in permafrost regions,as well as for improving the embankment stability and operational safety of the qinghai-Tibet Railway.

关键词： qinghai-Tibet Railway U-shaped crushed rock embankment Climate change Permafrost zone Ground temperature variation index Long-term coolingrole

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Significantly Enhanced Melt Memory Effect of Metallocene-made Isotactic Polypropylene Containing Talc

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Chinese Journal of Polymer Science 2024年第2期42卷 213-222,I0008页

作者： Hong-Wen Sun Fu-Shan Wang yan Gao Fu-qing Wei Jia-Chun Feng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China Lanzhou Petrochemical Corporation of PetroChina Lanzhou730060China Lanzhou Petrochemical Research Center Petrochemical Research Institute of PetroChinaLanzhou730060China

The melt memory effect is a widely observed phenomenon in semi-crystalline polymers. In practical applications, various additives are usually introduced into polymers, which may affect their melt memory behavior. In this work, the effect of talc on the melt memory effect of metallocene-made isotactic polypropylene(M-PP) was investigated in detail by using the differential scanning calorimetry. The results indicated that the introduction of talc significantly strengthened the melt memory effect of M-PP. Specifically, the upper limit temperature of Domain II increased from 161 ℃ to 174 ℃, resulting in a substantial widening of the temperature range of Domain IIa from 1 ℃ to 14 ℃. Analysis of the crystal orientation of the M-PP containing talc cooled from various Ts suggested that the remarkably enhanced melt memory effect could be ascribed to the stabilization of oriented nuclei facilitated by talc. This stabilizing effect was likely attributable to the prefreezing effect or the sorption interaction between talc and the M-PP chains.

关键词： Metallocene-made isotactic polypropylene Talc Melt memory effect Crystal orientation

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Reliability of DC-link capacitor in pulsed power supply for accelerator magnet

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Nuclear Science and Techniques 2024年第9期35卷 28-40页

作者： Jie Wang Da-qing Gao Wan-Zeng Shen Hong-Bin yan Li-Jun Mao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Capacitors are widely used in pulsed magnet power supplies to reduce ripple voltage,store energy,and decrease power *** this study,DC-link capacitors in pulsed power supplies were *** deriving an analytical method for the capacitor current on the H-bridge topology side,the root-mean-square value of the capacitor current was calculated,which helps in selecting the DC-link *** proposed method solves this problem quickly and with high *** current reconstruction of the DC-link capacitor is proposed to avoid structural damage in the capacitor’s current measurement,and the capacitor’s hotspot temperature and temperature rise are calculated using the FFT *** test results showed that the error between the calculated and measured temperature increases was within 1.5℃.Finally,the lifetime of DC-link capacitors was predicted based on Monte Carlo *** proposed method can evaluate the reliability of DC-link capacitors in a non-isolated switching pulsed power supply for accelerators and is also applicable to film capacitors.

关键词： Aluminum electrolytic capacitor DC-link current DC–DC power converter Hotspot temperature

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Multi-endpoint assays reveal more severe toxicity induced by chloraminated effluent organic matter than chloraminated natural organic matter

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Journal of Environmental Sciences 2024年第1期135卷 310-317页

作者： Hai-yan Wang De-Xiu wu Ye Du Xiao-Tong Lv Qian-Yuan wu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environmental Protection Key Laboratory of Microorganism Application and Risk Control Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental SafetyTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China College of Architecture and Environment Sichuan UniversityChengdu 610000China

Disinfection by chloramination produces toxic byproducts and the difference in toxicity of reclaimed and drinking water treated by chloramination remains *** study investigated cytotoxic effects at the same concentrations of dissolved organic matter and showed that chloraminated effluent organic matter(EfOM)induced 1.7 times higher cytotoxicity than chloraminated natural organic matter(NOM)applied to simulate drinking *** EfOM induced more reactive nitrogen species than chloraminated NOM,and chloraminated EfOM and NOM induced similar and higher levels of reactive oxygen species than the negative control,***,intracellular macromolecule damage indicated by DNA/RNA damage marker 8–hydroxy-(deoxy)guanosine and the intracellular protein carbonyl concentration induced by chloraminated EfOM was higher and slightly more than that induced by chloraminated NOM,*** data were consistent with the effects on cell physiological *** cycle arrest mainly occurred in G2 phase by chloraminated EfOM and *** apoptotic cells,which could return to normal,increased upon exposure to high concentrations of chloraminated EfOM and ***,necrotic cells were significantly increased from 0.5%to 2.5%when the concentration increased from 20-to 60-fold chloraminated EfOM,but were not obviously changed by chloraminated *** results indicated that the comprehensive intracellular changes induced by toxic substances in chloraminated EfOM were more irreversible and induced more cell death than chloraminated NOM.

关键词： Cytotoxicity Intracellular active nitrogen/oxygen Intracellular oxidative damage Cell necrosis Reclaimed water

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Portable fluorogenic probe for monitoring of volatile amine vapour and food spoilage

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Chinese Chemical Letters 2024年第3期35卷 257-261页

作者： Jian-Hao Zhao Wen-Xing Xu Bin Li Wei Xu wu-Kun Zhang Ming-Shuai Yuan Hui-Zi Li qing-Guo He Xiang Ma Jian-Gong Cheng yan-yan Fu State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of the Chinese Academy of SciencesBeijing 100039China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

There are urgent needs of volatile amine gas sensors with high-performance in food quality control,disease monitoring and environmental ***-film fluorescent probe is suitable for amine vapour sensing due to its high sensitivity,high selectivity,and no polluting ***,a novel fluorescent probe based on indacenodithiophene structure withπconjugated system was designed and *** experimental results show that the films prepared by this material exhibit rapid and distinct fluorescence quenching after being exposed to saturated vapours of primary amine,secondary amine and tertiary amine represented by n-propylamine,diethylamine and trimethylamine,*** quenching of fluorescence is 84%,87%and 96%,respectively,within 10 *** detection mechanism of probe for primary amine is based on specific chemical reaction,while the detection mechanism for secondary amine and tertiary amine is intramolecular charge *** experiments show that the detection limit of the fluorescent probe for trimethylamine,an important marker of food spoilage,could reach 4.610 ***-site detection based on spoilage of small yellow croaker suggests the material possesses the potential for food freshness *** simple fluorogenic probe is an original approach to simplify real-time visual monitoring of volatile amine vapour.

关键词： Fluorescent probe Volatile amine Gas sensing Trimethylamine Food spoilage

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Experimental investigation into the salinity effect on the physicomechanical properties of carbonate saline soil

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1883-1895页

作者： Jiejie Shen qing Wang Yating Chen Xuefei Zhang yan Han Yaowu Liu College of Construction Engineering Jilin UniversityChangchun130026China Shandong Zhengyuan Geological Resources Exploration Co.Ltd. Jinan250013China China Renewable Energy Engineering Institute Beijing100120China

For engineering structures with saline soil as a filling material,such as channel slope,road subgrade,etc.,the rich soluble salt in the soil is an important potential factor affecting their safety *** study examines the Atterberg limits,shear strength,and compressibility of carbonate saline soil samples with different NaHCO3 contents in Northeast *** mechanism underlying the influence of salt content on soil macroscopic properties was investigated based on a volumetric flask test,a mercury intrusion porosimetry(MIP)test,and a scanning electron microscopic(SEM)*** results demonstrated that when NaHCO3 contents were lower than the threshold value of 1.5%,the bound water film adsorbed on the surface of clay particles thickened continuously,and correspondingly,the Atterberg limits and plasticity index increased rapidly as the increase of sodium ion ***,the bonding force between particles was weakened,the dispersion of large aggregates was enhanced,and the soil structure became ***,the compressibility increased and the shear strength(mainly cohesion)decreased by 28.64%.However,when the NaHCO3 content exceeded the threshold value of 1.5%,the salt gradually approached solubility and filled the pores between particles in the form of crystals,resulting in a decrease in soil *** cementation effect generated by salt crystals increased the bonding force between soil particles,leading to a decrease in plasticity index and an improvement in soil mechanical ***,this work provides valuable suggestions and theoretical guidance for the scientific utilization of carbonate saline soil in backfill engineering projects.

关键词： Carbonate saline soil Salt content Physicomechanical properties Bound water Microstructure

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Retrieval of Antarctic sea ice freeboard and thickness from HY-2B satellite altimeter data

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Acta Oceanologica Sinica 2024年第3期43卷 87-101页

作者： Yizhuo Chen Xiaoping Pang qing Ji Zhongnan yan Zeyu Liang Chenlei Zhang Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Surveying and Mapping Science Ministry of Natural ResourcesWuhan 430079China Key Laboratory of Polar Environment Monitoring and Public Governance Ministry of EducationWuhan 430079China 4 School of Geography and Tourism Anhui Normal UniversityWuhu 241002China

Antarctic sea ice is an important part of the Earth’s atmospheric system,and satellite remote sensing is an important technology for observing Antarctic sea *** Chinese Haiyang-2B(HY-2B)satellite altimeter data could be used to estimate sea ice freeboard and provide alternative Antarctic sea ice thickness information with a high precision and long time series,as other radar altimetry satellites can,needs further *** paper proposed an algorithm to discriminate leads and then retrieve sea ice freeboard and thickness from HY-2B radar altimeter *** first collected the Moderate-resolution Imaging Spectroradiometer ice surface temperature(IST)product from the National Aeronautics and Space Administration to extract leads from the Antarctic waters and verified their accuracy through Sentinel-1 Synthetic Aperture Radar ***,a surface classification decision tree was generated for HY-2B satellite altimeter measurements of the Antarctic waters to extract leads and calculate local sea surface *** then estimated the Antarctic sea ice freeboard and thickness based on local sea surface heights and the static equilibrium ***,the retrieved HY-2B Antarctic sea ice thickness was compared with the CryoSat-2 sea ice thickness and the Antarctic Sea Ice Processes and Climate(ASPeCt)ship-based observed sea ice *** results indicate that our classification decision tree constructed for HY-2B satellite altimeter measurements was reasonable,and the root mean square error of the obtained sea ice thickness compared to the ship measurements was 0.62 *** proposed sea ice thickness algorithm for the HY-2B radar satellite fills a gap in this application domain for the HY-series satellites and can be a complement to existing Antarctic sea ice thickness products;this algorithm could provide long-time-series and large-scale sea ice thickness data that contribute to research on global climate change.

关键词： HY-2B satellite altimeter classification decision tree sea ice freeboard and thickness Antarctic waters

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Peripheral leukocyte count and risk of bleeding in patients with non-valvular atrial fibrillation taking dabigatran: a real-world study

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Chinese Medical Journal 2019年第18期132卷 2150-2156页

作者： Wei Zhou Tao Wang Ling-Juan Zhu Ming-Hua Wen Li-Hua Hu Xiao Huang Chun-Jiao You Ju-Xiang Li yan-qing wu qing-Hua wu Hui-Hui Bao Xiao-Shu Cheng Center for Prevention and Treatment of Cardiovascular Diseases The Second Affiliated Hospital of Nanchang University Nanchang Jiangxi 330006 China Department of Cardiovascular Medicine The Second Affiliated Hospital of Nanchang University Nanchang Jiangxi 330006 China

Background: The association between peripheral leukocyte count and bleeding events in nonvalvular atrial fibrillation (NVAF) patients treated with dabigatran remains unclear. This study aimed to explore the association between leukocyte count and bleeding events after excluding other confounders in NVAF patients taking dabigatran. Methods: A total of 851 NVAF patients treated with dabigatran (110 mg bid) were recruited from 12 centers in China from February 2015 to December 2017. Follow-up was completed by May 2018. The exposure and outcome variables were leukocyte count measured at baseline and the number of bleeding events within the subsequent 6 months. Multivariate Cox proportional hazards models were constructed to analyze independent associations, and a Cox proportional hazards regression with cubic spline functions and smooth curve fitting (penalized spline method) was used to address nonlinearity between leukocyte count and bleeding. The inflection point was calculated using a recursive algorithm, and then a two-piecewise Cox proportional hazards model for both sides of the inflection point was constructed. Results: During 6-month follow-up, 87 participants occurred bleeding events. For every 1×10^9/L increase in leukocyte count, the risk of bleeding increased by 11%(hazard ratio [HR]: 1.11, 95% confidence interval [CI]: 0.99–1.25). The smooth curve showed nonlinear relationship between leukocyte count and bleeding events. The inflection point of the leukocyte count was 6.75×10^9/L. For leukocyte counts < 6.75×10^9/L, the HR (95% CI) was 0.88 (0.69–1.13), and for leukocyte counts ≥ 6.75×10^9/L, the HR (95% CI) was 1.28 (1.09–1.51). Conclusion: This study found a J-shaped association between baseline leukocyte count and risk of bleeding in NVAF patients treated with dabigatran.

关键词： Peripheral leukocyte count Bleeding Nonvalvular atrial fibrillation Threshold effect

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The AaBBX21–AaHY5 module mediates light-regulated artemisinin biosynthesis in Artemisia annua L.

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Journal of Integrative Plant Biology 2024年第8期66卷 1735-1751页

作者： Weizhi He Hang Liu Zhangkuanyu wu qing Miao Xinyi Hu Xin yan Hangyu Wen Yaojie Zhang Xueqing Fu Li Ren Kexuan Tang Ling Li Frontiers Science Center for Transformative Molecules Joint International ResearchLaboratory of Metabolic and Developmental SciencesKey Laboratory of Urban Agriculture(South)Ministry of AgriculturePlant Biotechnology Research CenterFudan-SJTU-Nottingham Plant Biotechnology R&D CenterSchool of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China Institute for Agri-Food Standards and Testing Technology Shanghai Academy of Agricultural SciencesShanghai 201403China

The sesquiterpene lactone artemisinin is an important anti-malarial component produced by the glandular secretory trichomes of sweet wormwood(Artemisia annua L.).Light was previously shown to promote artemisinin production,but the underlying regulatory mechanism remains *** this study,we demonstrate that ELONGATED HYPOCOTYL5(HY5),a central transcription factor in the light signaling pathway,cannot promote artemisinin biosynthesis on its own,as the binding of AaHY5 to the promoters of artemisinin biosynthetic genes failed to activate their *** analysis and yeast two-hybrid screening revealed the B-box transcription factor AaBBX21 as a potential interactor with ***21 showed a trichome-specific expression ***,the AaBBX21–AaHY5 complex cooperatively activated transcription from the promoters of the downstream genes AaGSW1,AaMYB108,and AaORA,encoding positive regulators of artemisinin ***,AaHY5 and AaBBX21 physically interacted with the *** E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1(COP1).In the dark,AaCOP1 decreased the accumulation of AaHY5 and AaBBX21 and repressed the activation of genes downstream of the AaHY5–AaBBX21 complex,explaining the enhanced production of artemisinin upon light *** study provides insights into the central regulatory mechanism by which light governs terpenoid biosynthesis in the plant kingdom.

关键词： AaBBX21 AaHY5 AaCOP1 Artemisia annua L. artemisinin biosynthesis light

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Defined hydrogels for spinal cord organoids:challenges and potential applications

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Neural Regeneration Research 2024年第11期19卷 2329-2330页

作者： Wai Hon Chooi Yuewen wu Shi-yan Ng Institute of Molecular and Cell Biology(IMCB) Agency for ScienceTechnology and Research(A*STAR)SingaporeSingapore Department of Physiology Yong Loo Lin School of MedicineNational University of Singapore(NUS)SingaporeSingapore

Organoids of the central nervous system,primarily derived from pluripotent stem cells or neural stem cells,are three-dimensional tissue cultures with self-organizing *** exposed to the right combinations of signals,they differentiate into a 3D tissue consisting of complex cytoarchitecture and native cell types,including various neuron subtypes and glial *** features closely mimic native tissues,making them invaluable for developmental studies and disease *** recent years,spinal cord organoids(SCOs)have been developed to investigate spinal cord development,injuries,and various neurological *** an integral part of the central nervous system,SCOs play a vital role and serve as a site for studying both neurodevelopment and neurodegenerative diseases.

关键词： properties injuries primarily

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