期刊文献+
共找到66篇文章
< 1 2 4 >
每页显示 20 50 100
Protective mechanism of Paeoniae Radix Alba against chemical liver injury based on network pharmacology,molecular docking,and in vitro experiments
1
作者 Shuangqiao liu Xin liu +7 位作者 Sijia Jiang Min Fu Jinxi Hu jiaqi liu Xiaoxu Fan Yingtong Feng Shujing Zhang Jingxia Wang 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期55-66,共12页
Objective:To explore and validate the potential targets of Paeoniae Radix Alba(P.Radix,Bai Shao)in protecting against chemical liver injury through network pharmacology,molecular docking technology,and in vitro cell e... Objective:To explore and validate the potential targets of Paeoniae Radix Alba(P.Radix,Bai Shao)in protecting against chemical liver injury through network pharmacology,molecular docking technology,and in vitro cell experiments.Methods:Network pharmacology was used to identify the common potential targets of P.Radix and chemical liver injury.Molecular docking was used to fit the components,which were subsequently verified in vitro.A cell model of hepatic fibrosis was established by activating hepatic stellate cell(HSC)-LX2 cells with 10 ng/mL transforming growth factor-β1.The cells were exposed to different concentrations of total glucosides of paeony(TGP),the active substance of P.Radix,and then evaluated using the cell counting kit-8 assay,enzyme-linked immunosorbent assay,and western blot.Results:Analysis through network pharmacology revealed 13 key compounds of P.Radix,and the potential targets for preventing chemical liver injury were IL-6,AKT serine/threonine kinase 1,jun protooncogene,heat shock protein 90 alpha family class A member 1(HSP90AA1),peroxisome proliferator activated receptor gamma(PPARG),PTGS2,and CASP3.Gene Ontology(GO)enrichment analysis indicated the involvement of response to drugs,membrane rafts,and peptide binding.Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis revealed that the main pathways involved lipid and atherosclerosis and chemical carcinogenesis-receptor activation.Paeoniflorin and albiflorin exhibited strong affinity for HSP90AA1,PTGS2,PPARG,and CASP3.Different concentrations of TGP can inhibit the expression of COL-I,COL-III,IL-6,TNF-a,IL-1β,HSP-90a,and PTGS2 while increasing the expression of PPAR-γand CASP3 in activated HSC-LX2 cells.Conclusion:P.Radix primarily can regulate targets such as HSP90AA1,PTGS2,PPARG,CASP3.TGP,the main active compound of P.Radix,protects against chemical liver injury by reducing the inflammatory response,activating apoptotic proteins,and promoting the apoptosis of activated HSCs. 展开更多
关键词 Paeoniae Radix Alba Total glycosides of paeony Chemical liver injury Liver fibrosis Network pharmacology Hepatic stellate cells
下载PDF
Marine ecological risk assessment for the herbicide sulfometuron-methyl based on species sensitivity distribution approach
2
作者 jiaqi liu Fanping MENG +1 位作者 Shuhao DU Siyuan SHAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1493-1503,共11页
In recent years,herbicide sulfometuron-methyl(SM)has been used to kill the invasive plant Spartina alterniflora in some coastal areas of China,which may lead to the toxic effects on non-target marine organisms.The 96-... In recent years,herbicide sulfometuron-methyl(SM)has been used to kill the invasive plant Spartina alterniflora in some coastal areas of China,which may lead to the toxic effects on non-target marine organisms.The 96-h median effective concentrations(96-h EC50)of SM on six species of marine microalgae were measured in growth inhibition tests,and were then compared with other published toxicity data,based on which a method of species sensitivity distribution(SSD)was built to estimate the hazardous concentration of SM for 5%of species(HC5)and potentially affected fraction(PAF)for a certain concentration.Results indicate that SM exhibited a high toxicity to two species of green algae(Chlorella pacifica and Dunaliella salina)with a 96-h EC50 of 0.11 and 0.13 mg/L respectively,had a medium toxicity to two species of golden algae(Diacronema viridis and Isochrysis galbana)with a 96-h EC50 of 14.24 and 21.48 mg/L respectively,and showed a low toxicity to two species of diatoms(Skeletonema costatum and Phaeodactylum tricornutum)with a 96-h EC50 of 148.99 and>100 mg/L,respectively.The estimated values of HC5 and the predicted no-effect concentrations(PNEC)for SM were 0.077 and 0.015 mg/L,respectively.According to the current dosage for killing S.alterniflora in tidal flats in Fujian Province,China,SM entering the sea by spraying might cause the acute injury or death of 14%of marine species.This hazard could last for about a month for those sensitive species.Therefore,on the premise of inhibiting the growth of this invasive plant,the dosage of SM should be reduced as much as possible to avoid severe damage to the marine ecosystem.The results provide a valuable information for marine ecological risk assessment on SM and for marine environmental management. 展开更多
关键词 sulfometuron-methyl(SM) MICROALGAE acute toxicity species sensitivity distribution(SSD) marine ecological risk
下载PDF
MXene Lubricated Tribovoltaic Nanogenerator with High Current Output and Long Lifetime
3
作者 Wenyan Qiao Linglin Zhou +7 位作者 Zhihao Zhao Peiyuan Yang Di liu Xiaoru liu jiaqi liu Dongyang liu Zhong Lin Wang Jie Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期36-48,共13页
Tribovoltaic nanogenerators(TVNGs)have the characteristics of high current density,low matched impedance and continuous output,which is expected to solve the problem of power supply for small electronic devices.Howeve... Tribovoltaic nanogenerators(TVNGs)have the characteristics of high current density,low matched impedance and continuous output,which is expected to solve the problem of power supply for small electronic devices.However,wear occurrence in friction interface will seriously reduce the performance of TVNGs as well as lifetime.Here,we employ MXene solution as lubricate to improve output current density and lifetime of TVNG simultaneously,where a high value of 754 mA m^(-2)accompanied with a record durability of 90,000 cycles were achieved.By comparing multiple liquid lubricates with different polarity,we show that conductive polar liquid with MXene as additive plays a crucial role in enhancing the electrical output performance and durability of TVNG.Moreover,the universality of MXene solution is well demonstrated in various TVNGs with Cu and P-type Si,and Cu and N-GaAs as material pairs.This work may guide and accelerates the practical application of TVNG in future. 展开更多
关键词 Tribovoltaic nanogenerators Ultra-robust Interface wear Interface lubricant
下载PDF
An Ultra-Compact Broadband Polarizing Beam Splitter Utilizing Hybrid Plasmonic Waveguide
4
作者 Li Zhang jiaqi liu +1 位作者 Can Pan Yatao Yang 《China Communications》 SCIE CSCD 2023年第6期49-59,共11页
Polarizing beam splitter has rather significant applications in polarization diversity circuits and polarization multiplexing systems.In this paper,we present an asymmetric polarizing beam splitter utilizing hybrid pl... Polarizing beam splitter has rather significant applications in polarization diversity circuits and polarization multiplexing systems.In this paper,we present an asymmetric polarizing beam splitter utilizing hybrid plasmonic waveguide.The special hybrid structure with a hybrid waveguide and a dielectric waveguide can limit the energy of TE and TM modes to a different layer.Therefore,we can achieve beam splitting by adjusting the corresponding parameters of the two waveguides.First,we studied the influences of different structure parameters on the real part of the effective mode refractive index of the two waveguides,and obtained a set of parameters that satisfy the condition of strong coupling of TM mode and weak coupling of TE mode.Then,the performance of our proposed polarizing beam splitter is evaluated numerically.The length of the coupling section is only 4.1μm,and the propagation loss of TM and TE modes is 0.0025 d B/μm and 0.0031 d B/μm respectively.Additionally,the extinction ratios of TM and TE modes are 10.62 d B and 12.55 d B,respectively.Particularly,the proposed device has excellent wavelength insensitivity.Over the entire C-band,the fluctuation of the whole normalized output power is less than 0.03.In short,our proposed asymmetric polarizing beam splitter features ultra-compactness,low propagation loss,and broad bandwidth,which would provide promising applications in polarization multiplexing system and polarization diversity circuits relevant to optical interconnection. 展开更多
关键词 polarizing beam splitter hybrid plasmonic waveguide directional coupler polarization multiplexing systems
下载PDF
Analysis on Climatic Characteristics of High Temperature Weather in Longdong Region
5
作者 Meiyu LI Jiaping LI jiaqi liu 《Meteorological and Environmental Research》 CAS 2023年第4期12-16,共5页
Using meteorological data from 8 national basic meteorological observation stations in Qingyang City of Longdong region from 1972 to 2021,the causes and change characteristics of high-temperature weather were analyzed... Using meteorological data from 8 national basic meteorological observation stations in Qingyang City of Longdong region from 1972 to 2021,the causes and change characteristics of high-temperature weather were analyzed,and targeted countermeasures and suggestions were proposed for residents' production,life,and energy security supply affected by high-temperature weather.The results showed that①affected by global warming,the annual average temperature,annual average maximum temperature,annual extreme maximum temperature,days of daily maximum temperature≥30℃,and days of daily maximum temperature≥35℃in Longdong region were all showing an upward trend;②due to the different terrain and soil properties of the underlying surface,the increase in high temperature weather varied in different regions.Due to the influence of desert and hilly terrain,the frequency and days of high temperature occurrence were relatively high in the central and northern parts of Qingyang City.Due to the climate regulation of the Ziwuling Mountains,the days of high temperature in the central and southern parts was significantly less than that in the central and northern parts;③if the warm high pressure ridge on the Qinghai-Tibet Plateau developed strongly in summer,the temperature of the closed warm center reached 0-4℃on the 500 hPa of high-altitude weather map.If the warm air mass developed eastward,it often led to sustained high temperature weather in Longdong region;④when the El Nino phenomenon occurred,the subtropical high in the western Pacific developed strongly in summer,with a center located northward,which was stable,with little movement.It was dry,sunny,hot,and rainless in Longdong region,and the high temperature weather was more significant than that in normal years. 展开更多
关键词 High temperature weather Climate change Characteristics analysis
下载PDF
Development Model and Quantitative Prediction of Igneous Rock in S Oilfield, the Bohai Sea Area
6
作者 Xijie Wang Jianmin Zhang +2 位作者 Youchun Lai Shicong Lyu jiaqi liu 《Journal of Geoscience and Environment Protection》 2023年第5期174-185,共12页
The structure of S Oilfield of Bohai sea area in China is located in the low uplift slope zone of the Dongwa Laibei area in the Huanghekou depression. The target interval of the oilfield belongs to the Paleogene layer... The structure of S Oilfield of Bohai sea area in China is located in the low uplift slope zone of the Dongwa Laibei area in the Huanghekou depression. The target interval of the oilfield belongs to the Paleogene layered structural oil reservoir under the influence of igneous rocks. Due to the widespread development of igneous rocks, and the diversity of igneous rock types, the structure is complex, and the lateral changes are intense. The differences in volcanic eruption intensity and volcanic materials made the igneous rock masses overlap each other, with rapid changes in lithofacies, and complex seismic reflection structures. Therefore, it was difficult to carry out fine characterization of igneous rocks. Based on the lithofacies model, lithofacies combination types, and seismic response characteristics of volcanic mechanisms, this paper summarized three types of development models of volcanic mechanisms in the study area. At the same time, through technical means such as stratigraphic slicing, seismic attribute extraction, and attribute optimization analysis, the spatial distribution characteristics of various facies zones of igneous rocks at different stages were described in detail, achieving precise prediction of igneous rocks in Bozhong S Oilfield. During the development process of the oilfield, the technical research results guided the optimization of well locations and provided technical support for the efficient development of the oilfield. 展开更多
关键词 Igneous Rock Facies Model Volcanic Institutions Seismic Attribute
下载PDF
掺杂质子化石墨相氮化碳增强碳基太阳能电池中钙钛矿的结晶质量
7
作者 郭明星 刘文超 +3 位作者 黄均妍 刘佳琦 尹淑慧 冷静 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第2期390-398,I0004,共10页
钙钛矿层的品质极大影响钙钛矿太阳能电池性能.然而,在溶液法生成多晶钙钛矿膜过程中会不可避免地形成缺陷和陷阱位.通过在钙钛矿层中嵌入添加物改善钙钛矿晶化,用于减少和钝化缺陷是非常重要的.本文合成一种环境友好的二维纳米材料质... 钙钛矿层的品质极大影响钙钛矿太阳能电池性能.然而,在溶液法生成多晶钙钛矿膜过程中会不可避免地形成缺陷和陷阱位.通过在钙钛矿层中嵌入添加物改善钙钛矿晶化,用于减少和钝化缺陷是非常重要的.本文合成一种环境友好的二维纳米材料质子化石墨相氮化碳(p-g-C_(3)N_(4)),并掺杂于碳基钙太阳能电池的钙钛矿层中.实验证明,在钙钛矿前驱体溶液中添加p-g-C_(3)N_(4)不仅能调解碘铅甲胺(MAPbI_(3))结品的成核和生长速率,获得大晶粒尺寸的平滑表面,还能减少钙钛矿层的本征缺陷.质子化过程在氮化碳表面引入活性基团-NH_(2)/-NH_(3),它们和钙钛矿晶体表面N-H键发生强化学作用,有效地钝化电子陷阱,提高钙钛矿结晶质量.结果表明,与不掺杂的对照电池(效率为4.48%)和掺杂石墨相氮化碳(g-C_(3)N_(4))电池(效率为5.93%)相比,掺杂质子化石墨相氮化碳(p-g-C_(3)N_(4))的电池获得了6.61%的较高效率.本工作展示了一种通过掺杂改性添加物改善钙钛矿膜的简单方法,为碳基钙钛矿太阳能电池的低成本制备提供了建议. 展开更多
关键词 钙钛矿太阳能电池 碳对电极 p-g-C_(3)N_(4) 结晶质量 光电性能
下载PDF
多孔Nafion膜离子聚合物金属复合材料的制备及性能 被引量:3
8
作者 杜野 梁博 +8 位作者 张鹏 赵刚 赵金涛 王伟华 刘甲奇 马昊哲 王运鑫 王冠正 李政勋 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第7期132-140,共9页
离子聚合物金属复合材料(IPMC)是一种新型人工肌肉材料。传统IPMC的含水率较低,其电致动性能较差。文中采用微粒浸析法,利用纳米四氧化三铁粒子成功制备了多孔Nafion膜。多孔Nafion膜含水率是普通Nafion膜的2.5~4.3倍,并且随着纳米粒子... 离子聚合物金属复合材料(IPMC)是一种新型人工肌肉材料。传统IPMC的含水率较低,其电致动性能较差。文中采用微粒浸析法,利用纳米四氧化三铁粒子成功制备了多孔Nafion膜。多孔Nafion膜含水率是普通Nafion膜的2.5~4.3倍,并且随着纳米粒子含量的增加,含水率不断增大。多孔Nafion膜IPMC的输出位移、应变能密度(能量转换效率)和稳定工作时间分别是普通Nafion膜IPMC的1.6~2.5倍、2.8~4.8倍和1.7~2.1倍。总之,Nafion膜中多孔结构的存在提高了IPMC的电致动性能。 展开更多
关键词 离子聚合物金属复合材料 人工肌肉材料 多孔Nafion膜 电致动性能
下载PDF
In Situ Coupling Strategy for Anchoring Monodisperse Co_9S_8 Nanoparticles on S and N Dual?Doped Graphene as a Bifunctional Electrocatalyst for Rechargeable Zn–Air Battery 被引量:8
9
作者 Qi Shao jiaqi liu +4 位作者 Qiong Wu Qiang Li Heng?guo Wang Yanhui Li Qian Duan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第1期64-77,共14页
An in situ coupling strategy to prepare Co_9S_8/S and N dual?doped graphene composite(Co_9S_8/NSG) has been proposed. The key point of this strategy is the function?oriented design of organic compounds. Herein, cobalt... An in situ coupling strategy to prepare Co_9S_8/S and N dual?doped graphene composite(Co_9S_8/NSG) has been proposed. The key point of this strategy is the function?oriented design of organic compounds. Herein, cobalt porphyrin derivatives with sulfo groups are employed as not only the coupling agents to form and anchor Co_9S_8 on the graphene in situ, but also the heteroatom?doped agent to generate S and N dual?doped graphene. The tight coupling of multiple active sites endows the composite materials with fast electrochemical kinetics and excellent stability for both oxygen reduction reaction(ORR) and oxygen evolution reaction(OER). The obtained electrocatalyst exhibits better activity parameter(ΔE = 0.82 V) and smaller Tafel slope(47.7 mV dec^(-1) for ORR and 69.2 mV dec^(-1) for OER) than commercially available Pt/C and RuO_2. Most importantly, as electrocatalyst for rechargeable Zn–air battery, Co_9S_8/NSG displays low charge–discharge voltage gap and outstanding long?term cycle stability over 138 h compared to Pt/C–RuO_2. To further broaden its application scope, a homemade all?solid?state Zn–air battery is also prepared, which displays good charge–discharge performance and cycle performance. The function?oriented design of N_4?metallomacrocycle derivatives might open new avenues to strategic construction of high?performance and long?life multifunctional electrocatalysts for wider electro?chemical energy applications. 展开更多
关键词 In situ COUPLING strategy Porphyrin derivate DOPED GRAPHENE Metal sulfide BIFUNCTIONAL ELECTROCATALYST RECHARGEABLE Zn–air battery
下载PDF
CH4/N2 separation on methane molecules grade diameter channel molecular sieves with a CHA-type structure 被引量:8
10
作者 Hua Shang Yuping Li +3 位作者 jiaqi liu Xuan Tang Jiangfeng Yang Jinping Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第5期1044-1049,共6页
Samples of methane molecules grade diameter channel CHA-type molecular sieves(Chabazite-K, SAPO-34 and SSZ-13) were investigated using the adsorption separation of CH4/N2 mixtures. The isotherms recorded for CH4 and N... Samples of methane molecules grade diameter channel CHA-type molecular sieves(Chabazite-K, SAPO-34 and SSZ-13) were investigated using the adsorption separation of CH4/N2 mixtures. The isotherms recorded for CH4 and N2 follow a typical type-Ι behavior, which were fitted well with the Sips model(R2>0.999) and the selectivity was calculated using IAST theory. The results reveal that Chabazite-K has the highest selectivity(SCH4/N= 5.5).2 SSZ-13 has the largest capacity, which can adsorb up to a maximum of 30.957 cm3·g-1(STP) of CH4, due to it having the largest pore volume and surface area, but the lowest selectivity(SCH4/N2= 2.5). From the breakthrough test, we can conclude that SSZ-13 may be a suitable candidate for the recovery of CH4 from low concentration methane(CH4<20%) based on its larger pore volume and higher CH4 capacity. Chabazite-K is more suited to the separation of high concentration methane(CH4>50%) due to its higher selectivity. 展开更多
关键词 Molecular SIEVES Adsorption CH4/N2 SEPARATION BREAKTHROUGH
下载PDF
Polyoxometalate-based silica-supported ionic liquids for heterogeneous oxidative desulfurization in fuels 被引量:5
11
作者 Ming Zhang Miao Wang +5 位作者 Jiapeng Yang Hongping Li jiaqi liu Xiao Chen Wenshuai Zhu Huaming Li 《Petroleum Science》 SCIE CAS CSCD 2018年第4期882-889,共8页
With the aim of deep desulfurization, silica-supported polyoxometalate-based ionic liquids were successfully prepared by a one-pot hydrothermal process and employed in heterogeneous oxidative desulfurization of variou... With the aim of deep desulfurization, silica-supported polyoxometalate-based ionic liquids were successfully prepared by a one-pot hydrothermal process and employed in heterogeneous oxidative desulfurization of various sulfur compounds. The compositions and structures of the hybrid samples were characterized by various methods such as FT-IR, XPS, Raman,UV–Vis, wide-angle XRD and N_2 adsorption–desorption. The experimental results indicated that the hybrid materials presented a high dispersion of tungsten species and excellent catalytic activity for the removal of 4,6-dimethyldibenzothiophene without any organic solvent as extractant, and the sulfur removal could reach 100.0% under mild conditions.The catalytic performance on various substrates was also investigated in detail. After cycling seven cycles, the sulfur removal of the heterogeneous system still reached 93.0%. The GC-MS analysis results demonstrated that the sulfur compound was first adsorbed by the catalyst and subsequently oxidized to its corresponding sulfone. 展开更多
关键词 POLYOXOMETALATE SILICA-SUPPORTED IONIC liquid HETEROGENEOUS oxidative DESULFURIZATION
下载PDF
Comprehensive evaluation of the metabolic effects of porcine CRTC3 overexpression on subcutaneous adipocytes with metabolomic and transcriptomic analyses 被引量:2
12
作者 jiaqi liu Jie Li +5 位作者 Wentao Chen Xintao Xie Xingang Chu Teresa G.Valencak Yizhen Wang Tizhong Shan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第3期891-903,共13页
Background:Meat quality is largely driven by fat deposition,which is regulated by several genes and signaling pathways.The cyclic adenosine monophosphate(cAMP)-regulated transcriptional coactivator 3(CRTC3)is a coacti... Background:Meat quality is largely driven by fat deposition,which is regulated by several genes and signaling pathways.The cyclic adenosine monophosphate(cAMP)-regulated transcriptional coactivator 3(CRTC3)is a coactivator of cAMP response element binding protein(CREB)that mediates the function of protein kinase A(PKA)signaling pathway and is involved in various biological processes including lipid and energy metabolism.However,the effects of CRTC3 on the metabolome and transcriptome of porcine subcutaneous adipocytes have not been studied yet.Here,we tested whether porcine CRTC3 expression would be related to fat deposition in Heigai pigs(a local fatty breed in China)and Duroc×Landrace×Yorkshire(DLY,a lean breed)pigs in vivo.The effects of adenovirus-induced CRTC3 overexpression on the metabolomic and transcriptomic profiles of subcutaneous adipocytes were also determined in vitro by performing mass spectrometry-based metabolomics combined with RNA sequencing(RNA-seq).Results:Porcine CRTC3 expression is associated with fat deposition in vivo.In addition,CRTC3 overexpression increased lipid accumulation and the expression of mature adipocyte-related genes in cultured porcine subcutaneous adipocytes.According to the metabolomic analysis,CRTC3 overexpression induced significant changes in adipocyte lipid,amino acid and nucleotide metabolites in vitro.The RNA-seq analysis suggested that CRTC3 overexpression alters the expression of genes and pathways involved in adipogenesis,fatty acid metabolism and glycerophospholipid metabolism in vitro.Conclusions:We identified significant alterations in the metabolite composition and the expression of genes and pathways involved in lipid metabolism in CRTC3-overexpressing adipocytes.Our results suggest that CRTC3 might play an important regulatory role in lipid metabolism and thus affects lipid accumulation in porcine subcutaneous adipocytes. 展开更多
关键词 CRTC3 Energy metabolism Metabolomics OVEREXPRESSION Subcutaneous adipocytes TRANSCRIPTOMICS
下载PDF
Novel Kriging-Based Decomposed-Coordinated Approach for Estimating the Clearance Reliability of Assembled Structures 被引量:2
13
作者 Da Teng Yunwen Feng +3 位作者 Cheng Lu Chengwei Fei jiaqi liu Xiaofeng Xue 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第11期1029-1049,共21页
Turbine blisks are assembled using blades,disks and casings.They can endure complex loads at a high temperature,high pressure and high speed.The safe operation of assembled structures depends on the reliability of eac... Turbine blisks are assembled using blades,disks and casings.They can endure complex loads at a high temperature,high pressure and high speed.The safe operation of assembled structures depends on the reliability of each component.Monte Carlo(MC)simulation is commonly used to analyze structural reliability,but this method needs to run thousands of computations.In order to assess the clearance reliability of assembled structures in an efficient and precise manner,the novel Kriging-based decomposed-coordinated(DC)(DCNK)approach is proposed by integrating the DC strategy,the Kriging model and the importance sampling-based Markov chain(MCIS)technique.In this method,the DC strategy is used to decompose a multi-objective problem into many single-objective problems.The relationships between these many single-objectives and the overall objective are then coordinated.The Kriging model is applied to establish the limit state functions of the single-objectives and multi-objective problems,while the MCIS method is used to assess the structural assembled clearance reliability.Moreover,a highly nonlinear complex compound function is first utilized to verify the DCNK model from a mathematical perspective.Then,the reliability of an aeroengine high-pressure turbine(HPT)blade-tip radial running clearance(BTRRC)is analyzed to validate the DCNK approach by considering thermo-structural interaction.The analytical results show that the reliability is 0.9976 when the allowance value of the BTTRC is 1.7650×10^(−3)m.Compared with different methodologies(including direct simulation,the classical Kriging model,and the weighted response surface method(WRSM)),the proposed method holds obvious advantages in computing time and precision,as well as simulation efficiency and precision.The efforts of this paper provide a useful approach to analyzing assembled clearance reliability and contribute to the development of structural reliability theory. 展开更多
关键词 Kriging-based decomposed-coordinated approach assembled clearance reliability assessment importance
下载PDF
Influence of warm eddies on sound propagation in the Gulf of Mexico 被引量:1
14
作者 肖瑶 李整林 +2 位作者 李鋆 刘佳琪 Karim G Sabra 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第5期134-144,共11页
An automatic detection method is employed to identify and track eddies in the Gulf of Mexico. The physical parameters of the eddies, such as lifespan, radius, and distribution position are first examined and used to d... An automatic detection method is employed to identify and track eddies in the Gulf of Mexico. The physical parameters of the eddies, such as lifespan, radius, and distribution position are first examined and used to determine the spatio–temporal evolution of a strong warm eddy separated from the Mexico current. Then, the influence of this strong warm eddy on sound propagation during its lifespan are comprehensively analyzed with the parabolic equation and explained by using the normal mode and ray theories. Additionally, the influence of mesoscale eddies on the redistribution of total depth-integrated energy among the normal modes in the deep water is also discussed. The variation of arrival angle is investigated to explain the spreading acoustic energy caused by eddies. Overall, the results show that warm eddies can change the propagation paths and cause the convergence zone to broaden and approach the sound source. Moreover,the warm eddy can disperse sound energy and cause the total depth-integrated energy to incline to a lower normal mode.Throughout the whole of these three periods(eddy generating, eddy maturing, and eddy terminating), the fluctuation in the transmission loss is up to 30 dB(depending on the relative location of eddy center to the source). 展开更多
关键词 MESOSCALE EDDIES SOUND PROPAGATION mode coupling acoustic energy DISTURBANCE
原文传递
Numerical simulation and analysis of lithium plasma during low-pressure DC arc discharge 被引量:1
15
作者 邬润辉 柴忪 +2 位作者 刘佳琪 从拾源 孟刚 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第4期16-21,共6页
Alkali metal DC arc discharge has the characteristics of easy ionization,low power consumption,high plasma temperature and ionization degree,etc,which can be applied in aerospace vehicles in various ways.In this paper... Alkali metal DC arc discharge has the characteristics of easy ionization,low power consumption,high plasma temperature and ionization degree,etc,which can be applied in aerospace vehicles in various ways.In this paper,we calculate the physical property parameters of lithium vapor,one of the major alkali metals,and analyze the discharge characteristics of lithium plasma with the magnetohydrodynamic(MHD)model.The discharge effects between constant current and voltage sources are also compared.It is shown that the lithium plasma of DC arc discharge has relatively high temperature and current density.The peak temperature can reach tens of thousands of K,and the current density reaches 6 x 107 A m 2.Under the same rated power,the plasma parameters of the constant voltage source discharge are much higher than those of the constant current source discharge,which can be used as the preferred discharge mode for aerospace applications. 展开更多
关键词 DC DISCHARGE LITHIUM PLASMA NUMERICAL simulation LOW-PRESSURE ARC
下载PDF
Research on System Control and Energy Management Strategy of Flux-Modulated Compound-Structure Permanent Magnet Synchronous Machine 被引量:2
16
作者 jiaqi liu Chengde Tong +2 位作者 Zengfeng Jin Guangyuan Qiao Ping Zheng 《CES Transactions on Electrical Machines and Systems》 2017年第2期100-108,共9页
The flux-modulated compound-structure permanent magnet synchronous machine (CS-PMSM), composed of a brushless double rotor machine (DRM) and a conventional permanent magnet synchronous machine (PMSM), is a power split... The flux-modulated compound-structure permanent magnet synchronous machine (CS-PMSM), composed of a brushless double rotor machine (DRM) and a conventional permanent magnet synchronous machine (PMSM), is a power split device for plug-in hybrid electric vehicles. In this paper, its operating principle and mathematical model are introduced. A modified current controller with decoupled state feedback is proposed and verified. The system control strategy is simulated in Matlab, and the feasibility of the control system is proven. To improve fuel economy, an energy management strategy based on fuzzy logic controller is proposed and evaluated by the Urban Dynamometer Driving Schedule (UDDS) drive cycle. The results show that the total energy consumption is similar to that of Prius 2012. 展开更多
关键词 CS-PMSM energy management strategy flux-modulated hybrid electric vehicle system control
下载PDF
Information Transmitting and Cognition with a Spiking Neural Network Model
17
作者 杜莹 刘嘉琦 付士慧 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第9期24-27,共4页
Information encoding plays a crucial role in neuroscience. One of the fundamental questions in cognitive neuroscience is how the brain encodes external stimuli in the sensory cortex. We use a network model based on th... Information encoding plays a crucial role in neuroscience. One of the fundamental questions in cognitive neuroscience is how the brain encodes external stimuli in the sensory cortex. We use a network model based on the Hodgkin–Huxley type to study the information transmitting including its storage and recall. The model is inspired by psychological and neurobiological evidence on sequential memories. The model contains excitatory and inhibitory neurons with all-to-all connections whose architecture has two layers. A lower layer represents consecutive events during the information encoding process, and the upper layer is used to tag sequences of events represented in the lower layer. The spike-timing-dependent plasticity learning rule is used for sequential storage of excitatory connections between the modules. Computer simulations demonstrate that the synchronization status of multiple neurons is dependent on the network connectivity patterns, and also this model has good performance for different sequences of storage and recall. 展开更多
关键词 神经网络模型 信息 编码过程 连接模式 计算机模拟 神经科学 体系结构 刺激性
原文传递
Geological evolution of offshore pollution and its long-term potential impacts on marine ecosystems
18
作者 Qixing Zhou Simin Wang +5 位作者 jiaqi liu Xiangang Hu Yuxia liu Yuqing He Xuan He Xiaotong Wu 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第5期75-88,共14页
Populations and metropolitan centers are accumulated in coastal areas around the world.In view of the fact that they are geographically adjacent to coasts and intense anthropogenic activities,increasing global offshor... Populations and metropolitan centers are accumulated in coastal areas around the world.In view of the fact that they are geographically adjacent to coasts and intense anthropogenic activities,increasing global offshore pollution has been an important worldwide concern over the past several decades and has become a very serious problem that needs to be addressed urgently.Due to offshore pollution,various geological disasters occur in high frequency,including intensified erosion and salinization of coastal soils,frequent geological collapses and landslides and increasing seismic activities.Moreover,offshore pollution shows increasingly serious impacts on the topography and geomorphology of offshore and coastal areas,including coastal degradation,retreating coastlines and estuary delta erosion.Offshore sedimentation processes are strongly influenced by the pH changes of terrestrial discharges,and sedimentary dynamics have become extremely acute and complex due to offshore pollution.The seabed topography and hydrodynamic environment determine the fate and transport of pollutants entering offshore regions.Coastal estuaries,port basins and lagoons that have relatively moderate ocean currents and winds are more likely to accumulate pollutants.Offshore regions and undersea canyons can be used as conduits for transporting pollutants from the continent to the seabed.It is particularly noteworthy that the spatial/temporal distribution of species,community structures,and ecological functions in offshore areas have undergone unprecedented changes in recent decades.Due to increasing offshore pollution,the stable succession and development trend of marine ecosystems has been broken.It is thus important to identify and regulate the quantity,composition and transportation of pollutants in offshore regions and their behavior in marine ecosystems.In particular,crucial actions for stabilizing marine ecosystems,including increasing species and biodiversity,should be implemented to enhance their anti-interference capabilities.This review provides an overview of the current situation of offshore pollution,as well as major trends of pollutant fate and transportation from continent to marine ecosystems,transformation of pollutants in sediments,and their bioaccumulation and diffusion.This study retrospectively reviews the long-term geological evolution of offshore pollution from the perspective of marine geology,and analyses their long-term potential impacts on marine ecosystems.Due to ecological risks associated with pollutants released from offshore sediments,more research on the influence of global offshore pollution based on marine geology is undoubtedly needed. 展开更多
关键词 Global offshore pollution Geological evolution SEDIMENTATION Marine ecosystem Coastal area
下载PDF
Relationship between multifunctionality and rural sustainable development: Insights from 129 counties of the Sichuan Province, China
19
作者 Xuefeng Li jiaqi liu +1 位作者 Jin Jia Han Yang 《Chinese Journal of Population,Resources and Environment》 2022年第3期285-294,共10页
Rural areas are multifunctional and often have production,living,and ecological functions.The high-quality and balanced development of these three functions is key to sustainable rural development(SRD).Thus,the evalua... Rural areas are multifunctional and often have production,living,and ecological functions.The high-quality and balanced development of these three functions is key to sustainable rural development(SRD).Thus,the evaluation of SRD based on rural multifunctionality is of immense significance.This study clarifies the rela‐tionship between multifunctionality and sustainable rural development.An evaluation index system with six sub-components was established for calculating the SRD.In addition,we included 129 counties from the Sich‐uan Province in our case study,and used this index system to analyze the characteristics of rural multifunc‐tionality for evaluating the SRD.The results showed indisputable evidence of multifunctional development.At the county level,rural multifunctionality faces the challenge of insufficient and uneven development,particu‐larly in production functions.Significant spatial differences existed in rural multifunctional development,and the suburban counties generally performed better.Moreover,a mutually reinforcing relationship between pro‐duction,living,and ecological functions was established;however,there was still a significant gap in realizing SRD.Our results emphasize the necessity of a differentiated SRD strategy that should be formulated and imple‐mented based on rural multifunctionality differentiation rules.Our study offers useful guidance for realizing rural multifunctional and sustainable development. 展开更多
关键词 Sustainable rural development Rural multifunctionality Production-ecological-living function Spatial difference Index system Sichuan Province
下载PDF
Assessment of Reversibility in Pulmonary Hypertension Related to Congenital Heart Disease by Using Biomarkers and Clinical Features
20
作者 Liping Wang Mingjie Zhang +3 位作者 Xi Chen Yachang Pang jiaqi liu Zhuoming Xu 《Congenital Heart Disease》 SCIE 2022年第1期87-97,共11页
Background:Reversibility of pulmonary hypertension(PH)is closely related to the treatment options for and prognosis of children with congenital heart disease.Objective:We combined patient-specific clinical features in... Background:Reversibility of pulmonary hypertension(PH)is closely related to the treatment options for and prognosis of children with congenital heart disease.Objective:We combined patient-specific clinical features including diagnosis,age and echocardiographic results,and biomarkers of pulmonary vascular dysfunction to explore the noninvasive methods that can be used to accurately evaluate the reversibility of pulmonary hypertension in congenital heart disease(PH-CHD).Methods:Based on the preoperative systolic pulmonary arterial pressure(sPAP),70 CHD patients were divided into normal,PH-CHD suspected,and confirmed groups.Additionally,biomarkers of circulating endothelial cells(CECs),endothelin-1(ET-1),and endothelial nitric oxide synthase(eNOS)were detected.Patients were categorized into reversible(RPH)and irreversible(IRPH)groups according to the sPAP 6 months after surgery.Risk stratification was performed according to the clinical features and biomarkers.Results:CECs and ET-1 levels in the confirmed group were significantly higher.eNOS was higher in the confirmed and suspected groups than that in the normal group.CECs in the IRPH group were significantly higher compared to the RPH group.No such intergroup differences were observed with respect to ET-1 and eNOS levels.The ROC curve showed that the risk stratification was of high diagnostic value to evaluate reversibility.Conclusion:The CECs,eNOS,and ET-1 were closely related with PH-CHD.CECs and risk stratification have high practical value in assessing the reversibility of PH-CHD. 展开更多
关键词 Pulmonary hypertension in congenital heart disease risk stratification circulating endothelial cells ENDOTHELIN-1 endothelial nitric oxide synthase
下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部