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Strength and elastic modulus enhancement in Mg-Li-Al matrix composites reinforced by ex situ TiB2 particles via stir casting 被引量:1
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作者 jiawei sun Dehua Ding +4 位作者 Wencai Liu Guohua Wu Hongjie Liu Guangling Wei Hezhou Liu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第9期3574-3588,共15页
A novel Mg^(-1)0Li-3Al(wt.%,LA103)matrix composite reinforced by ex situ micron TiB_(2) particles was developed in the present study.The ball milling and cold pressing pretreatment of the reinforcements made it feasib... A novel Mg^(-1)0Li-3Al(wt.%,LA103)matrix composite reinforced by ex situ micron TiB_(2) particles was developed in the present study.The ball milling and cold pressing pretreatment of the reinforcements made it feasible to prepare this material under stir casting conditions with good dispersion.The microstructure and mechanical properties of the composites prepared by different pretreatment methods were analyzed in detail.The TiB_(2) particles in the Al-TiB_(2)/LA103 composite using the pretreatment process were uniformly distributed in the microstructure due to the formation of highly wettable core-shell units in the melt.Compared with the matrix alloys,the Al-TiB_(2)/LA103 composite exhibited effective strength and elastic modulus improvements while maintaining acceptable elongation.The strengthening effect in the composites was mainly attributed to the strong grain refining effect of TiB2.This work shows a balance of high specific modulus(36.1 GPa·cm^(3)·g^(-1))and elongation(8.4%)with the conventional stir casting path,which is of considerable application value. 展开更多
关键词 Mg-Li composite Stir casting Elastic modulus Microstructure Mechanical properties
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Microstructure evolution and enhanced fatigue behavior in the Mg-10Li-5Zn-0.5Er alloys micro-alloyed with Yb
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作者 Guanglan Liao Guohua Wu +4 位作者 Wencai Liu jiawei sun Lv Xiao Song Pang Peijun Chen 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第8期3159-3172,共14页
In this paper,(0.2-1 wt%)Yb was added to improve the tensile properties and high-cycle fatigue behavior of the as-cast and as-extruded Mg-10Li-5Zn-0.5Er alloys.It is found that Yb mainly affects the mechanical propert... In this paper,(0.2-1 wt%)Yb was added to improve the tensile properties and high-cycle fatigue behavior of the as-cast and as-extruded Mg-10Li-5Zn-0.5Er alloys.It is found that Yb mainly affects the mechanical properties of the alloy by changing the grain size,type and morphology of the second phases.Yb mainly exists in the formation of Mg_(2)Yb and Mg-Zn-Yb phases in the metallographic structure.With the addition of Yb,the grains are refined and these Yb-containing phases replace the large-sized MgLiZn phase to be enriched at the grain boundaries.While the addition of excess Yb reduces the number of small-sized MgLiZn phases in the grain,thus reducing the alloys’mechanical performance.After extrusion,the small-sized MgLiZn phase is refined and the number increases,which effectively improves the tensile and fatigue strength of the alloy.The fatigue strength is mainly affected by the number and morphology of the second phase,positively correlated with the strength.Balanced in grain size and number and size of second phases,the extruded alloy with 0.2Yb added exhibits excellent mechanical properties with the yield strength,ultimate tensile strength and elongation of 292 MPa,303 MPa and 11.7%,and an fatigue strength of 130 MPa. 展开更多
关键词 Mg-Li alloy YB MICROSTRUCTURE Fatigue property Hot extrusion
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Local Discontinuous Galerkin Methods for the abcd Nonlinear Boussinesq System 被引量:1
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作者 jiawei sun Shusen Xie Yulong Xing 《Communications on Applied Mathematics and Computation》 2022年第2期381-416,共36页
Boussinesq type equations have been widely studied to model the surface water wave.In this paper,we consider the abcd Boussinesq system which is a family of Boussinesq type equations including many well-known models s... Boussinesq type equations have been widely studied to model the surface water wave.In this paper,we consider the abcd Boussinesq system which is a family of Boussinesq type equations including many well-known models such as the classical Boussinesq system,the BBM-BBM system,the Bona-Smith system,etc.We propose local discontinuous Galerkin(LDG)methods,with carefully chosen numerical fluxes,to numerically solve this abcd Boussinesq system.The main focus of this paper is to rigorously establish a priori error estimate of the proposed LDG methods for a wide range of the parameters a,b,c,d.Numerical experiments are shown to test the convergence rates,and to demonstrate that the proposed methods can simulate the head-on collision of traveling wave and finite time blow-up behavior well. 展开更多
关键词 Local discontinuous Galerkin methods Boussinesq equations Coupled BBM equations Error estimate Numerical fluxes Head-on collision
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理性选择视野下政府购买社会组织服务研究——以W街道购买养老服务为例 被引量:1
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作者 孙佳伟 范明林 《中国社会工作研究》 CSSCI 2013年第1期96-129,共34页
本文在深入的个案研究基础上,运用科尔曼的理性选择理论怍为分析工具,把政府购买服务的双方视为科尔曼分析框架中信任关系的“委托人”和“受托人”。政府通过理性选择在不同的历史时期和社会组织发展程度的情况下,形成不同的购买服... 本文在深入的个案研究基础上,运用科尔曼的理性选择理论怍为分析工具,把政府购买服务的双方视为科尔曼分析框架中信任关系的“委托人”和“受托人”。政府通过理性选择在不同的历史时期和社会组织发展程度的情况下,形成不同的购买服务模式,以及管理、监督、评估制度,最重要的目的就是提升社会组织的可信任度。而社会组织也通过积极满足购买服务的要求,提供自身专业性的信息,来提升政府对其的信任度。因此,怍为本土化的购买服务的理性选择是基于“制度信任”和“组织信任”的双重机制。在此前提下,本文围绕两个理念(即“法制化”理念和“增权”理念),来深入讨论如何进一步完善政府购买服务的制度和模式。 展开更多
关键词 购买服务 社会组织 养老服务 理性选择理论
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Spatiotemporal Input Control:Leveraging Temporal Variation in Network Dynamics
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作者 Yihan Lin jiawei sun +4 位作者 Guoqi Li Gaoxi Xiao Changyun Wen Lei Deng H.Eugene Stanley 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第4期635-651,共17页
The number of available control sources is a limiting factor to many network control tasks.A lack of input sources can result in compromised controllability and/or sub-optimal network performance,as noted in engineeri... The number of available control sources is a limiting factor to many network control tasks.A lack of input sources can result in compromised controllability and/or sub-optimal network performance,as noted in engineering applications such as the smart grids.The mechanism can be explained by a linear timeinvariant model,where structural controllability sets a lower bound on the number of required sources.Inspired by the ubiquity of time-varying topologies in the real world,we propose the strategy of spatiotemporal input control to overcome the source-related limit by exploiting temporal variation of the network topology.We theoretically prove that under this regime,the required number of sources can always be reduced to 2.It is further shown that the cost of control depends on two hyperparameters,the numbers of sources and intervals,in a trade-off fashion.As a demonstration,we achieve controllability over a complex network resembling the nervous system of Caenorhabditis elegans using as few as 6%of the sources predicted by a static control model.This example underlines the potential of utilizing topological variation in complex network control problems. 展开更多
关键词 Complex network complex system control theory complex system optimization temporal network time-varying system
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LARGE TIME BEHAVIOR OF THE 1D ISENTROPIC NAVIER-STOKES-POISSON SYSTEM
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作者 Qingyou HE jiawei sun 《Acta Mathematica Scientia》 SCIE CSCD 2022年第5期1843-1874,共32页
The initial value problem(IVP)for the one-dimensional isentropic compressible Navier-Stokes-Poisson(CNSP)system is considered in this paper.For the variables,the electric field and the velocity,under the Lagrange coor... The initial value problem(IVP)for the one-dimensional isentropic compressible Navier-Stokes-Poisson(CNSP)system is considered in this paper.For the variables,the electric field and the velocity,under the Lagrange coordinate,we establish the global existence and uniqueness of the classical solutions to this IVP problem.Then we prove by the method of complex analysis,that the solutions to this system converge to those of the corresponding linearized system in the L^(2) norm as time tends to infinity.In addition,we show,using Green’s function,that the solutions to this system are close to a diffusion profile,pointwisely,as time goes to infinity. 展开更多
关键词 1D Navier-Stokes-Poisson system WELL-POSEDNESS L^(2)-time decay rates timespace pointwise behaviors
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Impact of oxygen in electrical properties and hot-carrier stress-induced degradation of GaN high electron mobility transistors
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作者 Lixiang Chen Min Ma +3 位作者 Jiecheng Cao jiawei sun Miaoling Que Yunfei sun 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第10期660-664,共5页
The role of the oxygen in AlGaN/GaN high electron mobility transistors(HEMTs)before and after semi-on state stress was discussed.Comparing with the electrical characteristics of the devices in vacuum,air,and oxygen at... The role of the oxygen in AlGaN/GaN high electron mobility transistors(HEMTs)before and after semi-on state stress was discussed.Comparing with the electrical characteristics of the devices in vacuum,air,and oxygen atmosphere,it is revealed that the oxygen has significant influence on the electric characteristics and the hot-carrier-stress-induced degradation of the device.Comparing with the situation in vacuum,the gate leakage increased an order of magnitude in oxygen and air atmosphere.Double gate structure was used to separate the barrier leakage and surface leakage of AlGaN/GaN HEMT it is found that surface leakage is the major influencing factor in gate leakage of SiN-passivated devices before and after semi-on state stress.During semi-on state stress in the oxygen atmosphere,the electric-field-driven oxidation process promoted the oxidation of the nitride layer,and the oxidation layer in the SiN/AlGaN interface leads to the decreasing of the surface leakage. 展开更多
关键词 semi-on state stress AlGaN/GaN HEMTs oxygen atmosphere
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TDB-250-3CL双工位吹塑机智能化生产线
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作者 邱建成 徐文良 +4 位作者 何建领 肖志林 秦超 孙佳伟 朱虞 《塑料包装》 CAS 2018年第5期39-43,共5页
本文介绍了200L三层危包桶双工位连续挤出智能化生产线的研制现状。
关键词 三层连续挤出机头 吹塑机生产线 多槽闸块锁模装置
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Influence of artificial freezing onliquefaction characteristics of Nanjing sand
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作者 Jie Zhou Zeyao Li +1 位作者 Wanjun Tian jiawei sun 《Railway Sciences》 2023年第1期13-32,共20页
Purpose–This study purposes to study the influence of artificial freezing on the liquefaction characteristics of Nanjing sand,as well as its mechanism.Design/methodology/approach–was studied through dynamic triaxial... Purpose–This study purposes to study the influence of artificial freezing on the liquefaction characteristics of Nanjing sand,as well as its mechanism.Design/methodology/approach–was studied through dynamic triaxial tests by means of the GDS dynamic triaxial system on Nanjing sand extensively discovered in the middle and lower reaches of the Yangtze River under seismic load and metro train vibration load,respectively,and potential hazards of the two loads to the freezing construction of Nanjing sand were also identified in the tests.Findings–The results show that under both seismic load and metro train vibration load,freeze-thaw cycles will significantly reduce the stiffness and liquefaction resistance of Nanjing sand,especially in the first freezethaw cycle;the more freeze-thaw cycles,the worse structural behaviors of silty-fine sand,and the easier to liquefy;freeze-thaw cycles will increase the sensitivity of Nanjing sand’s dynamic pore pressure to dynamic load response;the lower the freezing temperature and the effective confining pressure,the worse the liquefaction resistance of Nanjing sand after freeze-thaw cycles;compared to the metro train vibration load,the seismic load in Nanjing is potentially less dangerous to freezing construction of Nanjing sand.Originality/value–The research results are helpful to the construction of the artificial ground freezing of the subway crossing passage in the lower reaches of the Yangtze River and to ensure the construction safety of the subway tunnel and its crossing passage. 展开更多
关键词 METRO FOUNDATION Nanjing sand Artificial formation freezing method Sand liquefaction Dynamic triaxial test
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通过激光/分散系耦合增强氧化石墨烯的还原效果:实现大规模、低缺陷的石墨烯用于无折痕散热膜在先进柔性电子器件中的应用
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作者 孙佳惟 熊雨薇 +3 位作者 贾海洋 韩龙祥 叶雯 孙立涛 《Science Bulletin》 SCIE EI CAS CSCD 2024年第11期1716-1727,共12页
The advancement of flexible electronics demands improved components,necessitating heat dissipation membranes(HDMs)to exhibit high thermal conductivity while maintaining structural integrity and performance stability e... The advancement of flexible electronics demands improved components,necessitating heat dissipation membranes(HDMs)to exhibit high thermal conductivity while maintaining structural integrity and performance stability even after extensive deformation.Herein,we have devised a laser-modulated reduction technique for graphene oxide(GO),enabling the fabrication of high-quality,large-scale,lowdefect graphene,which yields high-performance HDMs after orderly deposition.The work underscores the crucial role of the laser wavelength and dispersion liquid's coupling intensity in influencing the morphology and properties of graphene.Optimal coupling effect and energy conversion are realized when a laser of 1064 nm wavelength irradiates a triethylene glycol(TEG)/N,N-Dimethylformamide(DMF)dispersion.This unique synergy generates high transient energy,which facilitates the deprotonation process and ensures a swift,comprehensive GO reduction.In contrast to conventional water-based laser reduction methods,the accelerated reaction magnifies the size of the graphene sheets by mitigating the ablation effect.After membrane construction with an ordered structure,the corresponding membrane exhibits a high thermal conductivity of 1632 W m^(-1)K^(-1),requiring only~1/10 of the total preparation time required by other reported methods.Remarkably,the resulting HDM demonstrates superior resilience against creasing and folding,maintaining excellent smoothness and negligible reduction in thermal conductivity after violent rubbing.The combination of exceptional flexibility and thermal conductivity in HDMs paves the way for long-term practical use in the flexible electronics industry. 展开更多
关键词 Laser-irradiation technology System coupling Graphene-based Heat dissipation membranes Crease-free
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Optimization of confined aquifer dewatering for long-deep excavation using simulation–optimization method
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作者 Yanxiao sun Zhenxiong Jiang +4 位作者 Liyuan Tong jiawei sun Jia Cui Xin Zhou Songyu Liu 《Underground Space》 SCIE EI CSCD 2024年第4期246-266,共21页
The confined aquifer dewatering for long-deep excavations usually encounters challenges due to complicated geotechnical conditions,large excavation sizes,and high hydraulic pressures.To propose the most efficient sche... The confined aquifer dewatering for long-deep excavations usually encounters challenges due to complicated geotechnical conditions,large excavation sizes,and high hydraulic pressures.To propose the most efficient scheme of confined aquifer dewatering for long-deep excavations,dewatering optimizations were performed using the simulation–optimization method.An open cut tunnel of the Jiangyin-Jingjiang Yangtze River Tunnel Project was taken as an example.The methods of finite element and linear programming(LP)were combined to optimize the dewatering process.A three-dimensional finite element model was developed.After simulating the pumping tests,hydraulic conductivity was inverted.Then,necessary parameters in the LP method were determined by simulating dewatering with each pumping well,and various LP models were developed based on some important influence factors such as dewatering sequence,considered pumping wells,and pumping rate limitation.Finally,the optimal pumping rates were solved and applied to the numerical model,with induced drawdown and ground settlement computed for comparison.The results indicate that the optimization can significantly reduce the required wells in the original design.Dewatering in the deepest zone exhibits the highest efficiency for long-deep excavations with gradually varying depths.For the dewatering sequence from the shallowest to the deepest zone,more pumping wells are required but less energy is consumed.Higher quantity and more advantageous locations of pumping wells in the LP model usually result in lower total pumping rate,drawdown,and ground settlement.If more pumping wells are considered in the deepest zone,pumping rate limitation of single well will only slightly increase the total pumping rate,number of required pumping wells,drawdown,and ground settlement. 展开更多
关键词 DEWATERING Confined aquifer Simulation-optimization Linear programming Open cut tunnel
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Chemical constituents from Portulaca oleracea and their bioactivities 被引量:13
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作者 Tianyun Jin Tao Shen +7 位作者 Mingxing Zhou Ailing Li Da Feng Bolun Zheng Jie Gong jiawei sun Lingyu Li Lan Xiang 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2016年第12期898-905,共8页
In the present study, we aimed to intensively study the chemical constituents, especially organic acids from a medicinal plant Portulaca oleracea L., and screen their anti-inflammatory and quinone reductase (QR, a ph... In the present study, we aimed to intensively study the chemical constituents, especially organic acids from a medicinal plant Portulaca oleracea L., and screen their anti-inflammatory and quinone reductase (QR, a phase II detoxyfication enzyme) inductive activity. A total of 20 compounds were isolated and identified based on spectroscopic methods, as succinic acid (1), mono-methyl succinate (2), L-malic acid (3), L-l-methyl malate (4), L-4-methyl malate (5), L-dimethyl malate (6), L-6-ethyl citrate (7), L-1-methyl citrate (8), L-1,5-dimethyl citrate (9), 4-hydroxy-5-methylfuran-3-carboxylic acid (10), 5-hydroxymethyl-furoic acid (11), stearic acid (12), L-pyroglutamic acid (13), cyclo-(tyrosine-leucine) (14), L-isoleucine (15), (-)-dehydrovomifoliol (16), (-)-epiloliolide (17), 3,4-dihydroxyphenylethanol (18), succinimide (19), and uracil (20). Among them, 14 compounds (2, 4-8, 10, 11, 13-18) were isolated from P. oleracea for the first time. Compotmd 18 (12.5 μM) exhibited potent anti-inflammatory effect in lipopolysaccharide (LPS)-induced macrophage cells (RAW264.7) by reducing NO production, and it also increased QR activity in Hepa lclc7 cells. Compound 16 (50 μM) showed weak QR inductive activity. None of other compounds showed anti-inflammatory or QR inductive activities. 展开更多
关键词 Portulaca oleracea Chemical constituents ANTI-INFLAMMATORY QR inductive activity
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Quantitative phase imaging through an ultra-thin lensless fiber endoscope 被引量:12
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作者 jiawei sun Jiachen Wu +6 位作者 Song Wu Ruchi Goswami Salvatore Girardo Liangcai Cao Jochen Guck Nektarios Koukourakis Juergen W.Czarske 《Light(Science & Applications)》 SCIE EI CAS CSCD 2022年第8期1843-1852,共10页
Quantitative phase imaging(QPI)is a label-free technique providing both morphology and quantitative biophysical information in biomedicine.However,applying such a powerful technique to in vivo pathological diagnosis r... Quantitative phase imaging(QPI)is a label-free technique providing both morphology and quantitative biophysical information in biomedicine.However,applying such a powerful technique to in vivo pathological diagnosis remains challenging.Multi-core fiber bundles(MCFs)enable ultra-thin probes for in vivo imaging,but current MCF imaging techniques are limited to amplitude imaging modalities.We demonstrate a computational lensless microendoscope that uses an ultra-thin bare MCF to perform quantitative phase imaging with microscale lateral resolution and nanoscale axial sensitivity of the optical path length.The incident complex light field at the measurement side is precisely reconstructed from the far-field speckle pattern at the detection side,enabling digital refocusing in a multi-layer sample without any mechanical movement.The accuracy of the quantitative phase reconstruction is validated by imaging the phase target and hydrogel beads through the MCF.With the proposed imaging modality,three-dimensional imaging of human cancer cells is achieved through the ultra-thin fiber endoscope,promising widespread clinical applications. 展开更多
关键词 FIBER phase THIN
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Downregulated cytotoxic CD8^(+)T-cell identifies with the NKG2A-soluble HLA-E axis as a predictive biomarker and potential therapeutic target in keloids 被引量:7
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作者 Heng Xu Zhu Zhu +6 位作者 Jian Hu jiawei sun Yan Wo Xianshu Wang Hongzhi Zou Bin Li Yixin Zhang 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2022年第4期527-539,共13页
Keloids are an abnormal fibroproliferative wound-healing disease with a poorly understood pathogenesis,making it difficult to predict and prevent this disease in clinical settings.Identifying disease-specific signatur... Keloids are an abnormal fibroproliferative wound-healing disease with a poorly understood pathogenesis,making it difficult to predict and prevent this disease in clinical settings.Identifying disease-specific signatures at the molecular and cellular levels in both the blood circulation and primary lesions is urgently needed to develop novel biomarkers for risk assessment and therapeutic targets for recurrence-free treatment.There is mounting evidence of immune cell dysregulation in keloid scarring.In this study,we aimed to profile keloid scar tissues and blood cells and found that downregulation of cytotoxic CD8^(+)T cells is a keloid signature in the peripheral blood and keloid lesions.Single-cell RNA sequencing revealed that the NKG2A/CD94 complex was specifically upregulated,which might contribute to the significant reduction in CTLs within the scar tissue boundary.In addition,the NKG2A/CD94 complex was associated with high serum levels of soluble human leukocyte antigen-E(sHLA-E).We subsequently measured sHLA-E in our hospital-based study cohort,consisting of 104 keloid patients,512 healthy donors,and 100 patients with an interfering disease.The sensitivity and specificity of sHLA-E were 83.69%(87/104)and 92.16%(564/612),respectively,and hypertrophic scars and other unrelated diseases exhibited minimal interference with the test results.Furthermore,intralesional therapy with triamcinolone combined with 5-fluorouracil drastically decreased the sHLA-E levels in keloid patients with better prognostic outcomes,while an incomplete reduction in the sHLA-E levels in patient serum was associated with higher recurrence.sHLA-E may effectively serve as a diagnostic marker for assessing the risk of keloid formation and a prognostic marker for the clinical outcomes of intralesional treatment. 展开更多
关键词 KELOID Biomarker T cell immunology
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Integration of chemical and biological methods:A case study of polycyclic aromatic hydrocarbons pollution monitoring in Shandong Peninsula,China 被引量:1
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作者 Zeyuan Li Yunhao Cao +3 位作者 Huawei Qin Yuanqing Ma Luqing Pan jiawei sun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第1期24-37,共14页
Polycyclic aromatic hydrocarbons(PAHs),as persistent toxic substances(PTS),have been widely monitored in coastal environment,including seawater and sediment.However,scientific monitoring methods,like ecological risk a... Polycyclic aromatic hydrocarbons(PAHs),as persistent toxic substances(PTS),have been widely monitored in coastal environment,including seawater and sediment.However,scientific monitoring methods,like ecological risk assessment and integrated biomarker response,still need massive researches to verify their availabilities.This study was performed in March,May,August and October of 2018 at eight sites,Yellow River estuary(S1),Guangli Port(S2),Xiaying(S3),Laizhou(S4),Inner Bay(S5),Outer Bay(S6),Hongdao(S7)and Hongshiya(S8)of Shandong Peninsula,China.The contents of 16 priority PAHs in local seawater and sediment were determined,by which ecological risk assessment risk quotient(RQ)for seawater and sediment quality guidelines(SQGs)were calculated to characterize the PAHs pollution.Meanwhile,multiple biomarkers in the digestive gland of clam Ruditapes philippinarum were measured to represent different biological endpoints,including ethoxyresorufin-O-deethylase(EROD),glutathione S-transferase(GST),sulfotransferase(SULT),superoxide dismutase(SOD)and lipid peroxidation(LPO),by which integrated biomarker response(IBR)was calculated to provide a comprehensive assessment of environmental quality.Taken together,these results revealed the heaviest pollution at S2 as both PAHs concentrations and biomarkers responses reflected,and supported the integrated biomarker response as a useful tool for marine environmental monitoring,through its integration with SQGs. 展开更多
关键词 Shandong Peninsula Polycyclic aromatic hydrocarbons(PAHs) Ruditapes philippinarum Risk quotient Sediment quality guidelines Integrated biomarker response
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Functional characterization of piggyBac-like elements from Nilaparvata lugens(St?l)(Hemiptera:Delphacidae)
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作者 Jun LYU Qin SU +3 位作者 Jinhui LIU Lin CHEN jiawei sun Wenqing ZHANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2022年第6期515-527,共13页
Piggy Bac is a transposable DNA element originally discovered in the cabbage looper moth(Trichoplusia ni).The T.ni piggyBac transposon can introduce exogenous fragments into a genome,constructing a transgenic organism... Piggy Bac is a transposable DNA element originally discovered in the cabbage looper moth(Trichoplusia ni).The T.ni piggyBac transposon can introduce exogenous fragments into a genome,constructing a transgenic organism.Nevertheless,the comprehensive analysis of endogenous piggyBac-like elements(PLEs)is important before using piggyBac,because they may influence the genetic stability of transgenic lines.Herein,we conducted a genome-wide analysis of PLEs in the brown planthopper(BPH)Nilaparvata lugens(St?l)(Hemiptera:Delphacidae),and identified a total of 28 PLE sequences.All N.lugens piggy Bac-like elements(NlPLEs)were present as multiple copies in the genome of BPH.Among the identified NlPLEs,NlPLE25 had the highest copy number and it was distributed on five chromosomes.The full length of NlPLE25 consisted of terminal inverted repeats and sub-terminal inverted repeats at both terminals,as well as a single open reading frame transposase encoding546 amino acids.Furthermore,NlPLE25 transposase caused precise excision and transposition in cultured insect cells and also restored the original TTAA target sequence after excision.A cross-recognition between the NlPLE25 transposon and the piggy Bac transposon was also revealed in this study.These findings provide useful information for the construction of transgenic insect lines. 展开更多
关键词 Nilaparvata lugens piggyBac-like elements TRANSPOSON NlPLE25
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Compressive holographic sensing simplifies quantitative phase imaging
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作者 jiawei sun Juergen W.Czarske 《Light(Science & Applications)》 SCIE EI CSCD 2023年第6期946-948,共3页
Quantitative phase imaging (QPI) has emerged as method for investigating biological specimen and technical objects. However, conventional methods often suffer from shortcomings in image quality, such as the twin image... Quantitative phase imaging (QPI) has emerged as method for investigating biological specimen and technical objects. However, conventional methods often suffer from shortcomings in image quality, such as the twin image artifact. A novel computational framework for QPI is presented with high quality inline holographic imaging from a single intensity image. This paradigm shift is promising for advanced QPI of cells and tissues. 展开更多
关键词 HOLOGRAPHIC PHASE SHORTCOMINGS
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