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Quantifying the Role of the Eddy Transfer Coefficient in Simulating the Response of the Southern Ocean Meridional Overturning Circulation to Enhanced Westerlies in a Coarse-resolution Model
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作者 yiwen li Hailong liU +3 位作者 Pengfei liN Eric PCHASSIGNET Zipeng YU Fanghua WU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1853-1867,共15页
This study assesses the capability of a coarse-resolution ocean model to replicate the response of the Southern Ocean Meridional Overturning Circulation(MOC) to intensified westerlies,focusing on the role of the eddy ... This study assesses the capability of a coarse-resolution ocean model to replicate the response of the Southern Ocean Meridional Overturning Circulation(MOC) to intensified westerlies,focusing on the role of the eddy transfer coefficient(κ).κ is a parameter commonly used to represent the velocities induced by unresolved eddies.Our findings reveal that a stratification-dependent κ,incorporating spatiotemporal variability,leads to the most robust eddy-induced MOC response,capturing 82% of the reference eddy-resolving simulation.Decomposing the eddy-induced velocity into its vertical variation(VV) and spatial structure(SS) components unveils that the enhanced eddy compensation response primarily stems from an augmented SS term,while the introduced VV term weakens the response.Furthermore,the temporal variability of the stratification-dependent κ emerges as a key factor in enhancing the eddy compensation response to intensified westerlies.The experiment with stratification-dependent κ exhibits a more potent eddy compensation response compared to the constant κ,attributed to the structure of κ and the vertical variation of the density slope.These results underscore the critical role of accurately representing κ in capturing the response of the Southern Ocean MOC and emphasize the significance of the isopycnal slope in modulating the eddy compensation mechanism. 展开更多
关键词 eddy transfer coefficient mesoscale eddy parameterization enhanced westerlies Southern Ocean Meridional Overturning Circulation ocean model
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High-Value-Added Utilization of Turpentine:Screening of Anti-Influenza Virus Agents fromβ-Pinene Derivatives
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作者 yiwen li Hongyan Si +7 位作者 Peng Wang Hai Luo Minggui Shen Xiaoping Rao Zhanqian Song Shibin Shang Zongde Wang Shengliang liao 《Journal of Renewable Materials》 EI CAS 2024年第1期45-56,共12页
Turpentine is a renewable and resourceful forest product.The deep processing and utilization of turpentine,particularly its primary componentβ-pinene,has garnered widespread attention.This study aimed to synthesize 4... Turpentine is a renewable and resourceful forest product.The deep processing and utilization of turpentine,particularly its primary componentβ-pinene,has garnered widespread attention.This study aimed to synthesize 40 derivatives ofβ-pinene,including nopinone,3-cyanopyridines of nopinone,myrtanyl acid,myrtanyl acylthioureas,and myrtanyl amides.We assessed the antiviral activities of theseβ-pinene derivatives against influenza virus A/Puerto Rico/8/34(H1N1)using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method.Theβ-pinene derivatives were used before and after cellular infection with the influenza virus to evaluate their preventive and therapeutic effects against the H1N1 virus.The results showed that only compound 10o exhibited a preventive effect against the H1N1 virus with a half-maximal inhibitory concentration(IC50)value of 47.6μmol/L.Among the compounds,4e,4i,and 4l demonstrated therapeutic effects against cellular infection,with compound 4e displaying the most potent therapeutic effect(IC50=17.5μmol/L),comparable to the positive control ribavirin.These findings indicated that certainβ-pinene derivatives exhibited in vitro antiviral activity against the H1N1 influenza A virus,warranting further investigation as potential anti-influenza agents. 展开更多
关键词 Antiviral activity Β-PINENE DERIVATIVE 3-CYANOPYRIDINE influenza virus
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Bifidobacterium longum CCFM1077 Attenuates Hyperlipidemia by Modulating the Gut Microbiota Composition and Fecal Metabolites:A Randomized,Double-Blind,Placebo-Controlled Clinical Trial
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作者 Chuanqi Chu Jinchi Jiang +8 位作者 Leilei Yu yiwen li Songli Zhang Wei Zhou Qun Wang Jianxin Zhao Qixiao Zhai Fengwei Tian Wei Chen 《Engineering》 SCIE EI CAS CSCD 2023年第9期193-205,共13页
An increasing number of studies have indicated that gut microbiota and its metabolites are crucial in the development of hyperlipidemia.Bifidobacterium longum(B.longum)CCFM1077 has been shown to have lipid-lowering ef... An increasing number of studies have indicated that gut microbiota and its metabolites are crucial in the development of hyperlipidemia.Bifidobacterium longum(B.longum)CCFM1077 has been shown to have lipid-lowering effects in animals.This study aimed to evaluate the potential of B.longum CCFM1077 in lowering the lipid levels in patients with hyperlipidemia and investigate the effect of this bacterium on serum lipid abnormalities,gut microbiota,and fecal metabolites in these patients.This study was a six-week,randomized,double-blind,and placebo-controlled pilot clinical trial.Subjects with hyperlipidemia(N=62)were randomly assigned to receive placebo(N=31)or B.longum CCFM1077(1×1010colony-forming units(CFUs)per day;N=31).Serum lipid levels including total cholesterol(TC),lowdensity lipoprotein cholesterol(LDL-C),total triglyceride(TG),and high-density lipoprotein cholesterol(HDL-C)were examined at the baseline and interventio nal endpoints.Changes in the gut microbiota composition and diversity were measured based on 16S ribosomal RNA(rRNA)sequencing of the V3-V4region at the end of the intervention period.Non-targeted metabolomics of the feces was performed using ultra-performance liquid chromatography(UPLC)-Q-Exactive Orbitrap/mass spectrometer.Oral administration of B.longum CCFM1077 for six weeks significantly decreased the serum levels of TC(p<0.01)and LDL-C(p<0.01)in patients with hyperlipidemia.B.longum CCFM1077 treatment markedly increased gut microbiota diversity and the relative abundance of anti-obesity-related genera,including Lactobacillus,Butyricicoccus,Bifidobacterium,and Blautia,whereas it decreased the relative abundance of obesity-related genera,including Alistipes,Megamonas,and Catenibacterium.Additionally,some key metabolites(bile acids(BAs),biotin,and caffeine)and their corresponding metabolic pathways(primary BA biosynthesis,and taurine and hypotaurine,biotin,purine,and caffeine metabolisms)were enriched by B.longum CCFM1077,and thus it may lower lipid levels.B.longum CCFM1077 is a probiotic strain with the potential to lower serum TC and LDL-C levels patients with hyperlipidemia.The underlying mechanism may be related to the increased abundance of anti-obesity-related genera and fecal metabolites.These findings provide a foundation for future clinical applications of lipid-lowering probiotics in managing individuals with hyperlipidemia. 展开更多
关键词 PROBIOTICS Bifidobacterium longum HYPERLIPIDEMIA Gut microbiota Fecal metabolites Bile acid(BA)
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LICOM Model Datasets for the CMIP6 Ocean Model Intercomparison Project 被引量:15
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作者 Pengfei liN Zhipeng YU +14 位作者 Hailong liU Yongqiang YU yiwen li Jirong JIANG Wei XUE Kangjun CHEN Qian YANG Bowen ZHAO Jilin WEI Mengrong DING Zhikuo SUN Yaqi WANG Yao MENG Weipeng ZHENG Jinfeng MA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第3期239-249,共11页
The datasets of two Ocean Model Intercomparison Project(OMIP)simulation experiments from the LASG/IAP Climate Ocean Model,version 3(LICOM3),forced by two different sets of atmospheric surface data,are described in thi... The datasets of two Ocean Model Intercomparison Project(OMIP)simulation experiments from the LASG/IAP Climate Ocean Model,version 3(LICOM3),forced by two different sets of atmospheric surface data,are described in this paper.The experiment forced by CORE-II(Co-ordinated Ocean–Ice Reference Experiments,Phase II)data(1948–2009)is called OMIP1,and that forced by JRA55-do(surface dataset for driving ocean–sea-ice models based on Japanese 55-year atmospheric reanalysis)data(1958–2018)is called OMIP2.First,the improvement of LICOM from CMIP5 to CMIP6 and the configurations of the two experiments are described.Second,the basic performances of the two experiments are validated using the climatological-mean and interannual time scales from observation.We find that the mean states,interannual variabilities,and long-term linear trends can be reproduced well by the two experiments.The differences between the two datasets are also discussed.Finally,the usage of these data is described.These datasets are helpful toward understanding the origin system bias of the fully coupled model. 展开更多
关键词 OMIP CMIP6 ocean sea-ice model model bias
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Molecular genetic and genomic analysis of wheat milling and end-use traits in China:Progress and perspectives 被引量:7
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作者 Daowen Wang Kunpu Zhang +4 位作者 lingli Dong Zhenying Dong yiwen li Abrar Hussain Huijie Zhai 《The Crop Journal》 SCIE CAS CSCD 2018年第1期68-81,共14页
Wheat is the most widely cultivated staple food crop, and multiple types of food derivatives are processed and consumed globally. Wheat grain quality(WGQ) is central to food processing and nutritional value, and is a ... Wheat is the most widely cultivated staple food crop, and multiple types of food derivatives are processed and consumed globally. Wheat grain quality(WGQ) is central to food processing and nutritional value, and is a decisive factor for consumer acceptance and commercial value of wheat cultivars. Hence, improvement in WGQ traits is top priority for both conventional and molecular wheat breeding. In this review we will focus on two important WGQ traits, grain milling and end-use, and will summarize recent progress in China. Chinese scientists have invested substantial effort in molecular genetic and genomic analysis of these traits and their effects on end-use properties. The insights and resources generated have contributed to the understanding and improvement of these traits. As high-quality genomics information and powerful genome engineering tools are becoming available for wheat, more fundamental breakthroughs in dissecting the molecular and genomic basis of WGQ are expected. China will strive to make further significant contributions to the study and improvement of WGQ in the genomics era. 展开更多
关键词 GENOMICS GLUTEN protein GRAIN hardness PUROINDOLINE WHEAT GRAIN quality
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Eddy-resolving Simulation of CAS-LICOM3 for Phase 2 of the Ocean Model Intercomparison Project 被引量:7
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作者 yiwen li Hailong liU +15 位作者 Mengrong DING Pengfei liN Zipeng YU Yongqiang YU Yao MENG Yunlong li Xiaodong JIAN Jinrong JIANG Kangjun CHEN Qian YANG Yaqi WANG Bowen ZHAO Jilin WEI Jinfeng MA Weipeng ZHENG and Pengfei WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第10期1067-1080,共14页
A 61-year(1958–2018)global eddy-resolving dataset for phase 2 of the Ocean Model Intercomparison Project has been produced by the version 3 of Chinese Academy of Science,the State Key Laboratory of Numerical Modeling... A 61-year(1958–2018)global eddy-resolving dataset for phase 2 of the Ocean Model Intercomparison Project has been produced by the version 3 of Chinese Academy of Science,the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics/Institute of Atmospheric Physics(LASG/IAP)Climate system Ocean Model(CAS-LICOM3).The monthly and a part of the surface daily data in this study can be accessed on the Earth System Grid Federation(ESGF)node.Besides the details of the model and experiments,the evolutions and spatial patterns of large-scale and mesoscale features are also presented.The mesoscale features are reproduced well in the high-resolution simulation,as the mesoscale activities can contribute up to 50%of the total SST variability in eddy-rich regions.Also,the large-scale circulations are remarkably improved compared with the low-resolution simulation,such as the climatological annual mean SST(the RMSE is reduced from 0.59°C to 0.47°C,globally)and the evolution of Atlantic Meridional Overturning Circulation.The preliminary evaluation also indicates that there are systematic biases in the salinity,the separation location of the western boundary currents,and the magnitude of eddy kinetic energy.All these biases are worthy of further investigation. 展开更多
关键词 eddy-resolving dataset mesoscale eddies CAS-LICOM3 OMIP
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Erratum to:LICOM Model Datasets for the CMIP6 OceanModel Intercomparison ProjectLICOM Model Datasets for the CMIP6 OceanModel Intercomparison Project
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作者 Pengfei liN Zipeng YU +14 位作者 Hailong liU Yongqiang YU yiwen li Jinrong JIANG Wei XUE Kangjun CHEN Qian YANG Bowen ZHAO Jilin WEI Mengrong DING Zhikuo SUN Yaqi WANG Yao MENG Weipeng ZHENG Jinfeng MA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第6期662-662,共1页
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Structural disruption of melanin-like polymers with boosted UV protection
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作者 Zhen Yang Xianheng Wang +3 位作者 Wanjie Bai Zikun Zou Haoxing Wu yiwen li 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第5期1653-1663,共11页
Manipulating the energy structure of materials represents an efficient way to regulate their light absorption behaviors. For example, constructing donor-acceptor(D-A) structures to increase the polarizability and redu... Manipulating the energy structure of materials represents an efficient way to regulate their light absorption behaviors. For example, constructing donor-acceptor(D-A) structures to increase the polarizability and reduce the energy bandgap of local molecules has been widely used in the field of organic photovoltaics with ordered structures. Remarkably, even in disordered and chaotic systems such as melanin-like polydopamine(PDA), visible and near-infrared light absorption can be significantly improved using this strategy. However, there has been a noticeable dearth of research on the ultraviolet(UV) light absorption regulation of bioinspired polymers with disordered and chaotic architectures by tailoring the D-A microstructures. In this study, a series of benzoheterocyclic molecules with strong electron-donating features screened by molecular simulation calculations were involved in disrupting the D-A structures within PDA. The destruction of D-A structures promoted the increase of the energy band gap and finally boosted the UV absorption of PDA. The resulting PDA nanoparticles with enhanced UV absorption were further employed to fabricate UV shielding composite films to protect the growth of plants from harmful UV radiation. This research may open up new avenues for structural disruption of bioinspired polymers for enhanced photoprotection applications. 展开更多
关键词 melanin-like polymers POLYDOPAMINE D-A structure UV absorption PHOTOPROTECTION
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日用工艺陶瓷实验创新基础课教学与产教融合路径研究 被引量:1
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作者 张美萍 李亦文 魏忠 《江苏陶瓷》 CAS 2020年第4期8-11,共4页
本文以与宜兴万宝日用工艺陶瓷生产企业合作的日用工艺陶瓷实验创新基础课程教学为实验对象,从企业和院校优势和价值触点分析出发,开展了长达半年的以产教融合为导向的基础课教学实验。通过这次实验,探讨了南京工业大学浦江学院"... 本文以与宜兴万宝日用工艺陶瓷生产企业合作的日用工艺陶瓷实验创新基础课程教学为实验对象,从企业和院校优势和价值触点分析出发,开展了长达半年的以产教融合为导向的基础课教学实验。通过这次实验,探讨了南京工业大学浦江学院"工本位"教育理念下产教融合创新模式的可行性,并提出了重视助推企业发展的"价值融合点"的产教融合实现路径。 展开更多
关键词 日用工艺陶瓷 实验课程 产教融合 价值融合点 以教助产
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Powdery mildew disease resistance and markerassisted screening at the Pm60 locus in wild diploid wheat Triticum urartu 被引量:3
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作者 Fukai Zhao Yinghui li +9 位作者 Baoju Yang Hongbo Yuan Cong Jin lixun Zhou Hongcui Pei lifang Zhao yiwen li Yilin Zhou Jiankun Xie Qian-Hua Shen 《The Crop Journal》 SCIE CAS CSCD 2020年第2期252-259,共8页
Triticum urartu,a diploid wild wheat and progenitor of the A genome of bread wheat,is an important resource for resistance to powdery mildew fungus caused by Blumeria graminis f.sp.tritici(Bgt).In the present study we... Triticum urartu,a diploid wild wheat and progenitor of the A genome of bread wheat,is an important resource for resistance to powdery mildew fungus caused by Blumeria graminis f.sp.tritici(Bgt).In the present study we systematically characterized the interaction between the Bgt fungus and T.urartu at the microscopic level.We also tested 227 T.urartu accessions for reaction to Bgt isolate E09 and discovered previously uncategorized powdery mildew resistance in this collection.Pm60 is a CC-NB-LRR type powdery mildew resistance gene that has at least three functional alleles,Pm60,Pm60a,and Pm60b.A marker-assisted screen targeting the Pm60 locus identified a non-functional allele of Pm60a,designated as Pm60a′.A sequence comparison of Pm60a′and Pm60a revealed that they differed by 58 SNPs and one 3-nucleotide deletion.Based on the sequence variations two molecular markers were developed to differentiate the functional Pm60a allele from the non-functional Pm60a′.Our screen revealed the presence of a previously uncharacterized powdery mildew resistance in T.urartu and provides new insights into the Pm60 locus.We believe that the two molecular markers developed here and new T.urartu resistant accessions will facilitate further identification of novel powdery mildew resistance genes and benefit breeding for powdery mildew resistance. 展开更多
关键词 TRITICUM BREEDING resistance
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The Super-large Ensemble Experiments of CAS FGOALS-g3 被引量:2
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作者 Pengfei liN Bowen ZHAO +15 位作者 Jilin WEI Hailong liU Wenxia ZHANG Xiaolong CHEN Jie JIANG Mengrong DING Wenmin MAN Jinrong JIANG Xu ZHANG Yuewen DING Wenrong BAI Chenyang JIN Zipeng YU yiwen li Weipeng ZHENG Tianjun ZHOU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第10期1746-1765,I0021-I0025,共25页
A super-large ensemble simulation dataset with 110 members has been produced by the fully coupled model FGOALS-g3 developed by researchers at the Institute of Atmospheric Physics,Chinese Academy of Sciences.This is th... A super-large ensemble simulation dataset with 110 members has been produced by the fully coupled model FGOALS-g3 developed by researchers at the Institute of Atmospheric Physics,Chinese Academy of Sciences.This is the first dataset of large ensemble simulations with a climate system model developed by a Chinese modeling center.The simulation has the largest realizations up to now worldwide in terms of single-model initial-condition large ensembles.Each member includes a historical experiment(1850-2014)and an experiment(2015-99)under the very high greenhouse gas emissions Shared Socioeconomic Pathway scenario(SSP5-8.5).The dataset includes monthly and daily temperature,precipitation,and other variables,requiring storage of 275 TB.Additionally,the surface air temperature(SAT)and land precipitation simulated by the FGOALS-g3 super-large ensemble have been validated and projected.The ensemble can capture the response of SAT and land precipitation to external forcings well,and the internal variabilities can be quantified.The availability of more than 100 realizations will help researchers to study rare events and improve the understanding of the impact of internal variability on forced climate changes. 展开更多
关键词 large ensemble forced response internal variability climate change
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FGOALS-g3 Model Datasets for CMIP6 Flux-Anomaly-Forced Model Intercomparison Project 被引量:2
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作者 Yaqi WANG Zipeng YU +14 位作者 Pengfei liN Hailong liU Jiangbo JIN lijuan li Yanli TANG li DONG Kangjun CHEN yiwen li Qian YANG Mengrong DING Yao MENG Bowen ZHAO Jilin WEI Jinfeng MA and Zhikuo SUN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第10期1093-1101,共9页
The Flux-Anomaly-Forced Model Intercomparison Project(FAFMIP)is an endorsed Model Intercomparison Project in phase 6 of the Coupled Model Intercomparison Project(CMIP6).The goal of FAFMIP is to investigate the spread ... The Flux-Anomaly-Forced Model Intercomparison Project(FAFMIP)is an endorsed Model Intercomparison Project in phase 6 of the Coupled Model Intercomparison Project(CMIP6).The goal of FAFMIP is to investigate the spread in the atmosphere–ocean general circulation model projections of ocean climate change forced by increased CO2,including the uncertainties in the simulations of ocean heat uptake,global mean sea level rise due to ocean thermal expansion and dynamic sea level change due to ocean circulation and density changes.The FAFMIP experiments have already been conducted with the Flexible Global Ocean–Atmosphere–Land System Model,gridpoint version 3.0(FGOALS-g3).The model datasets have been submitted to the Earth System Grid Federation(ESGF)node.Here,the details of the experiments,the output variables and some baseline results are presented.Compared with the preliminary results of other models,the evolutions of global mean variables can be reproduced well by FGOALS-g3.The simulations of spatial patterns are also consistent with those of other models in most regions except the North Atlantic and the Southern Ocean,indicating large uncertainties in the regional sea level projections of these two regions. 展开更多
关键词 FAFMIP CMIP6 global mean sea level rise dynamic sea level change
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Kuroshio intrusion in the Luzon Strait in an eddy-resolving ocean model and air-sea coupled model 被引量:1
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作者 Qian Yang Hailong liu +1 位作者 Pengfei lin yiwen li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第11期52-68,共17页
The Kuroshio intrusion in a quasi-global eddy-resolving model(LICOMH)and a fully air-sea coupled mode(LICOMHC)was evaluated against observations.We found that the Kuroshio intrusion was exaggerated in the former,while... The Kuroshio intrusion in a quasi-global eddy-resolving model(LICOMH)and a fully air-sea coupled mode(LICOMHC)was evaluated against observations.We found that the Kuroshio intrusion was exaggerated in the former,while biases were significantly attenuated in the latter.Luzon Strait transport(LST)in winter was reduced from–8.8×106 m3/s in LICOMH to–6.0×106 m3/s in LICOMHC.Further analysis showed that different LST values could be explained by different large-scale and local surface wind stresses and the eddies east to the Luzon Strait as well.The relatively stronger cyclonic eddies in LICOMH northeast of the Luzon Island led to weak Kuroshio transport and strong intrusion through the Luzon Strait.The summed transport of all three factors was approximately 2.0×106 m3/s,which was comparable with the difference in LST between the two experiments.The EKE budget showed that strong EKE transport and the baroclinic transformation term led to strong cyclonic eddies east of the Kuroshio in LICOMH,while surface winds contributed little to the differences in the eddies. 展开更多
关键词 Kuroshio intrusion South China Sea eddy-resolving model air-sea coupled model
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Manipulating the antioxidative capacity of melanin-like nanoparticles by involving condensation polymerization 被引量:1
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作者 Peng Yang Tianyou Wang +7 位作者 Jianhua Zhang Hengjie Zhang Wanjie Bai Gaigai Duan Wei Zhang Jinrong Wu Zhipeng Gu yiwen li 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第5期1520-1528,共9页
Melanin is ubiquitous in nature and plays important roles in physiological activities especially in keeping the oxidative balance.Both natural and synthetic melanin were synthesized via the free radical polymerization... Melanin is ubiquitous in nature and plays important roles in physiological activities especially in keeping the oxidative balance.Both natural and synthetic melanin were synthesized via the free radical polymerization of 5,6-dihydroxyindole(DHI)monomer,which may lead to the inherent compactπ-conjugation stacking microstructures and finally results in limited antioxidative capacities.To address this issue,we have strived to involve condensation polymerization during the melanin synthetic process,aiming to disrupt the compact stacking microstructures and improve the total antioxidative performance.The resulting melaninlike nanoparticles(NPs)indeed possessed less compact stackingπ-conjugation structures and decreased density,which further demonstrated enhanced antioxidative abilities compared with conventional melanin-like polymers such as poly-5,6-dihydroxyindole(Poly-DHI)and polydopamine(PDA).Their excellent free radical scavenging capability was further confirmed by the intracellular cell protection effects against reactive oxygen species(ROS)as well as in vivo therapy for acute diseases including acute kidney injury and acute liver injury.This work would promote future work toward new types of melanin-inspired nanomaterials with tunable and improved functions beyond nature. 展开更多
关键词 MELANIN condensation polymerization free radical polymerization POLYDOPAMINE antioxidative-therapy
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A Bioinspired Strategy Toward UV Absorption Enhancement of Melaninlike Polymers for Sun Protection 被引量:1
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作者 Zhen Yang Jianhua Zhang +7 位作者 Huijie liu Junfei Hu Xianheng Wang Wanjie Bai Wei Zhang Ye Yang Zhipeng Gu yiwen li 《CCS Chemistry》 CSCD 2023年第10期2389-2402,共14页
Due to the complexity of the structure within melanin and synthetic polymers(i.e.,polydopamine,PDA),it is a challenge to regulate the ultraviolet(UV)absorption.In nature,melanocytes can biosynthesize more pheomelanins... Due to the complexity of the structure within melanin and synthetic polymers(i.e.,polydopamine,PDA),it is a challenge to regulate the ultraviolet(UV)absorption.In nature,melanocytes can biosynthesize more pheomelanins than eumelanins via protein and gene overexpression for photoprotection when the UV irradiation is enhanced.During this biosynthetic pathway,L-cystine,transported by xCT gene,can be involved to form a new monomer structure incorporating a benzothiazole group,finally resulting in the formation of UV absorption-enhanced pheomelanin.Inspired by this,we have proposed a facile strategy to regulate the UV absorption of PDA by introducing the benzimidazole(BI)unit through the thiol-Michael addition reaction during the polymerization process.It was further found that the introduction of BI units not only significantly increased the content of chromophores and auxochromes,but also effectively restricted the red-shift of the absorption spectrum via interrupting the conjugated microstructure within PDA,both of which contribute to UV absorption enhancement.These UV absorption-enhanced PDA nanoparticles could be used to fabricate bio-inspired sunscreens for efficient sun protection.This work will provide a facile strategy to regulate UV absorption of melanin-like materials and open new horizons for the design and construction of bioinspired sunscreens. 展开更多
关键词 MELANIN sun protection POLYDOPAMINE UV absorption
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Experimental study on nanosecond pulsed pin-to-plate discharge in supersonic air flow
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作者 yiwen li zhong ZHUANG +3 位作者 Lei PANG Pengzhen DUAN Zhiwen DING Bailing ZHANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第6期122-131,共10页
Development of magnetohydrodynamic acceleration technology is expected to improve wind tunnel simulation capability and testing capability.The underlying premise is to produce uniform and stable plasma in supersonic a... Development of magnetohydrodynamic acceleration technology is expected to improve wind tunnel simulation capability and testing capability.The underlying premise is to produce uniform and stable plasma in supersonic air flow,and gas discharge is an effective way to achieve this.A nanosecond pulsed discharge experimental system under supersonic conditions was established,and a pin-to-plate nanosecond pulsed discharge experiment in Mach 2 air flow was performed to verify that the proposed method produced uniform and stable plasma under supersonic conditions.The results show that the discharge under supersonic conditions was stable overall,but uniformity was not as good as that under static conditions.Increasing the number of pins improved discharge uniformity,but reduced discharge intensity and hence plasma density.Under multi-pin conditions at 1000Hz,the discharge was almost completely corona discharge,with the main current component being the displacement current,which was smaller than that under static conditions. 展开更多
关键词 nanosecond pulse DISCHARGE SUPERSONIC air flow pin-to-plate DISCHARGE plasma UNIFORM and stable
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Stimulating and harnessing circularly polarized luminescence of helically assembled carbonized polymer dots via interfacial dynamics
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作者 Jiaying lin Rulin liu +9 位作者 Peixian Chen Yangfei Lv Junjie Hao Meijuan Chen Dongxiang Zhang Ruikun Pan yiwen li Xi Zhu Tingchao He Jiaji Cheng 《Aggregate》 2023年第4期100-110,共11页
Stimulating and harnessing circularly polarized luminescence(CPL)is not only a sine qua non for fundamentally unveiling chirogenesis in physical chemistry,but also a pivotal prerequisite for implementation of such phe... Stimulating and harnessing circularly polarized luminescence(CPL)is not only a sine qua non for fundamentally unveiling chirogenesis in physical chemistry,but also a pivotal prerequisite for implementation of such phenomenon in research fields including chiral optoelectronics and theranostics.Herein,red-emissive carbonized polymer dots(CPDs)-based helical structures were synthesized in this work via biomolecule-tailored organic–inorganic co-assembly strategy.The surface statesrelated chirality exhibits enhanced circular dichroism(CD)and CPL activities with anisotropic factors as high as gCD,max=5.4×10^(−3) and glum,max=1.5×10^(−2),respectively.The obtained CPL signals can be further manipulated in an excitationdependent manner,indicating that a synergistic-competition phenomenon exists between configurational chirality and intermolecular energy-transfer dynamics,which is further supported by simulations based on density function theory(DFT).Such tunable CPL behavior triggers revolutionary designs and applications of these chiral CPDs into the realm of chirality-related biological issues and next-generation chiral optoelectronics. 展开更多
关键词 carbonized polymer dots circular dichroism circularly polarized luminescence organic-inorganic coassembly synergistic-competition
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关注口腔-肠道菌群互作:糖尿病冠心病机制研究的新视角
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作者 李逸雯 刘艳飞 刘玥 《科学通报》 EI CAS CSCD 北大核心 2024年第26期3843-3845,共3页
近年心血管代谢医学(Cardiometabolic Medicine)已成为备受关注的亚专业.糖尿病对心脏损伤的不良影响是由遗传易感性与环境因素共同决定的.其中,菌群是环境因素中与人体最密切的因素之一.口腔与胃肠黏膜物理上相连,也已有大量研究提出... 近年心血管代谢医学(Cardiometabolic Medicine)已成为备受关注的亚专业.糖尿病对心脏损伤的不良影响是由遗传易感性与环境因素共同决定的.其中,菌群是环境因素中与人体最密切的因素之一.口腔与胃肠黏膜物理上相连,也已有大量研究提出不同定植部位之间(如口腔和肠道)的菌群可相互影响,但遗憾的是多数为关联性研究[1]. 展开更多
关键词 心脏损伤 胃肠黏膜 糖尿病冠心病 环境因素 遗传易感性 肠道菌群 关联性研究 口腔
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Machine learning-assisted wearable sensor array for comprehensive ammonia and nitrogen dioxide detection in wide relative humidity range 被引量:1
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作者 yiwen li Shuai Guo +9 位作者 Boyi Wang Jianguo Sun liupeng Zhao Tianshuang Wang Xu Yan Fangmeng liu Peng Sun John Wang Swee Ching Tan Geyu Lu 《InfoMat》 SCIE CSCD 2024年第6期95-109,共15页
The fast booming of wearable electronics provides great opportunities for intelligent gas detection with improved healthcare of mining workers,and a variety of gas sensors have been simultaneously developed.However,th... The fast booming of wearable electronics provides great opportunities for intelligent gas detection with improved healthcare of mining workers,and a variety of gas sensors have been simultaneously developed.However,these sensing systems are always limited to single gas detection and are highly susceptible to the inference of ubiquitous moisture,resulting in less accuracy in the analysis of gas compositions in real mining conditions.To address these challenges,we propose a synergistic strategy based on sensor integration and machine learning algorithms to realize precise NH_(3) and NO_(2) gas detections under real mining conditions.A wearable sensing array based on the graphene and polyaniline composite is developed to largely enhance the sensitivity and selectivity under mixed gas conditions.Further introduction of backpropagation neural network(BP-NN)and partial least squares(PLS)algorithms could improve the accuracy of gas identification and concentration prediction and settle the inference of moisture,realizing over 99%theoretical prediction level on NH_(3) and NO_(2) concentrations within a wide relative humidity range,showing great promise in real mining detection.As proof of concept,a wireless wearable bracelet,integrated with sensing arrays and machine-learning algorithms,is developed for wireless real-time warning of hazardous gases in mines under different humidity conditions. 展开更多
关键词 bismuth oxyselenide device applications preparation methods properties two-dimensional material
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配体对映选择性触发的热激活碳化聚合物点表面态手性异构化
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作者 周宾倩 郝俊杰 +8 位作者 刘汝林 雷茜 敖秀琴 崔妍妍 张蕾 李以文 贺廷超 朱熹 程佳吉 《中国科学:化学》 CAS CSCD 北大核心 2024年第8期1369-1379,共11页
碳化聚合物点(CPDs)的选择性异构化与手性光学活性调控是多层次手性纳米材料的研究前沿问题.实现其表面态电子跃迁的可控手性效应是创制可见-近红外光区域内圆偏振光电器件与医用材料的重要基础.基于此,本文拟通过简单热激活的触发方式... 碳化聚合物点(CPDs)的选择性异构化与手性光学活性调控是多层次手性纳米材料的研究前沿问题.实现其表面态电子跃迁的可控手性效应是创制可见-近红外光区域内圆偏振光电器件与医用材料的重要基础.基于此,本文拟通过简单热激活的触发方式将N-乙酰-L/D-半胱氨酸的分子手性诱导至非手性CPDs上,通过有机配体与CPDs表面的界面手性诱导效应,实现表面态手性异构化与手性信号的调制与反转.研究表明,N-乙酰-L/D-半胱氨酸分子的用量以及热激活时间的长短等因素对CPDs中基于表面态的圆二色谱(g_(CD,max)~1.28×10^(-3))以及圆偏振发光光谱(g_(lum,max)~2.1×10^(-2))信号峰的位置与强弱都有着重要影响.相关密度泛函理论(DFT)数理模型分析指出手性配体在CPDs表面吸附的不对称性极有可能是产生该现象的原因。 展开更多
关键词 碳化聚合物点 圆二色谱 热激活 手性反转 圆偏振发光
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