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Research on Adaptability Analysis of Environmental Space Demand and Design Optimization of Daycare Centers: Taking Chongqing’s Community F as an Example
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作者 Tijin Gui Minna Yu +1 位作者 Bin Chen jun tao 《Journal of World Architecture》 2024年第3期49-56,共8页
Currently,there is a lack of research on the detailed environmental spatial design of community daycare centers at the micro level.This study focuses on Community F in Chongqing,using the elderly’s“willingness to de... Currently,there is a lack of research on the detailed environmental spatial design of community daycare centers at the micro level.This study focuses on Community F in Chongqing,using the elderly’s“willingness to demand”as a central aspect.It examines indoor and outdoor environmental space needs at a micro level,considering both functional requirements and spiritual needs based on existing research.The analysis incorporates three adaptive elements:current construction,surrounding environment,and operational management.It explores the feasibility of restructuring spatial layouts,utilizing local resources,and integrating Bayu cultural characteristics.Finally,through design optimization practices,the study proposes three strategies for aging optimization:functional integration and interaction,user-friendly facilities,and emotional connections to place. 展开更多
关键词 Daycare center Environmental space Willingness to demand Design optimization
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近β型钛合金线性摩擦焊接头变形行为及组织演变的热物理模拟 被引量:1
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作者 郭震国 马铁军 +4 位作者 杨夏炜 李文亚 陶军 李菊 Achilleas VAIRIS 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第2期481-493,共13页
为了更好地理解近β型钛合金线性摩擦焊(LFW)接头的界面连接行为,采用热压缩物理模拟的方法,以TB2近β型钛合金为研究材料,设计符合LFW工艺特点的帽形热压缩试样,在不同下压量、变形温度及应变速率条件下进行热压缩试验,研究热压缩接头... 为了更好地理解近β型钛合金线性摩擦焊(LFW)接头的界面连接行为,采用热压缩物理模拟的方法,以TB2近β型钛合金为研究材料,设计符合LFW工艺特点的帽形热压缩试样,在不同下压量、变形温度及应变速率条件下进行热压缩试验,研究热压缩接头的变形行为及组织演变。结果表明,热压缩过程中热压缩接头连接区(BZ)的峰值剪切应力随变形温度的降低及应变速率的增加而增大,接头BZ的宽度随变形温度和应变速率的增加而减小。接头BZ边缘由沿剪切方向变形的晶粒组成,接头BZ中心由细小的等轴再结晶晶粒组成。接头的动态再结晶机制为连续动态再结晶(CDRX),且CDRX的程度随下压量、变形温度及应变速率的增加而增大。此外,在界面剪切力的作用下接头BZ边缘形成{112}[111]织构,接头BZ中心形成{110}[001]织构。 展开更多
关键词 线性摩擦焊 TB2近β钛合金 热物理模拟 变形行为 组织演变 织构演变
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Federated Learning with Blockchain for Privacy-Preserving Data Sharing in Internet of Vehicles 被引量:3
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作者 Wenxian Jiang Mengjuan Chen jun tao 《China Communications》 SCIE CSCD 2023年第3期69-85,共17页
Data sharing technology in Internet of Vehicles(Io V)has attracted great research interest with the goal of realizing intelligent transportation and traffic management.Meanwhile,the main concerns have been raised abou... Data sharing technology in Internet of Vehicles(Io V)has attracted great research interest with the goal of realizing intelligent transportation and traffic management.Meanwhile,the main concerns have been raised about the security and privacy of vehicle data.The mobility and real-time characteristics of vehicle data make data sharing more difficult in Io V.The emergence of blockchain and federated learning brings new directions.In this paper,a data-sharing model that combines blockchain and federated learning is proposed to solve the security and privacy problems of data sharing in Io V.First,we use federated learning to share data instead of exposing actual data and propose an adaptive differential privacy scheme to further balance the privacy and availability of data.Then,we integrate the verification scheme into the consensus process,so that the consensus computation can filter out low-quality models.Experimental data shows that our data-sharing model can better balance the relationship between data availability and privacy,and also has enhanced security. 展开更多
关键词 blockchain federated learning PRIVACY data sharing Internet of Vehicles
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Identification of Dynamic Active Sites Among Cu Species Derived from MOFs@CuPc for Electrocatalytic Nitrate Reduction Reaction to Ammonia 被引量:3
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作者 Xue‑Yang Ji Ke Sun +5 位作者 Zhi‑Kun Liu Xinghui Liu Weikang Dong Xintao Zuo Ruiwen Shao jun tao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第8期20-34,共15页
Direct electrochemical nitrate reduction reaction(NITRR)is a promising strategy to alleviate the unbalanced nitrogen cycle while achieving the electrosynthesis of ammonia.However,the restructuration of the high-activi... Direct electrochemical nitrate reduction reaction(NITRR)is a promising strategy to alleviate the unbalanced nitrogen cycle while achieving the electrosynthesis of ammonia.However,the restructuration of the high-activity Cu-based electrocatalysts in the NITRR process has hindered the identification of dynamical active sites and in-depth investigation of the catalytic mechanism.Herein,Cu species(single-atom,clusters,and nanoparticles)with tunable loading supported on N-doped TiO_(2)/C are successfully manufactured with MOFs@CuPc precursors via the pre-anchor and post-pyrolysis strategy.Restructuration behavior among Cu species is co-dependent on the Cu loading and reaction potential,as evidenced by the advanced operando X-ray absorption spectroscopy,and there exists an incompletely reversible transformation of the restructured structure to the initial state.Notably,restructured CuN_(4)&Cu_(4) deliver the high NH_(3) yield of 88.2 mmol h^(−1)g_(cata)^(−1) and FE(~94.3%)at−0.75 V,resulting from the optimal adsorption of NO_(3)^(−) as well as the rapid conversion of^(*)NH_(2)OH to^(*)NH_(2) intermediates originated from the modulation of charge distribution and d-band center for Cu site.This work not only uncovers CuN_(4)&Cu_(4) have the promising NITRR but also identifies the dynamic Cu species active sites that play a critical role in the efficient electrocatalytic reduction in nitrate to ammonia. 展开更多
关键词 Metal-organic frameworks Copper phthalocyanine Electrocatalytic nitrate reduction reaction
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Composition and antioxidant activity of Paeonia lactiflora petal flavonoid extract and underlying mechanisms of the protective effect on H_(2)O_(2)-induced oxidative damage in BRL3A cells
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作者 Lei Liu Yingdan Yuan +1 位作者 Jiajia Zuo jun tao 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第2期335-344,共10页
Flavonoids have attracted considerable attention due to their health benefits. This study aimed to investigate the flavonoid profiles and antioxidant activity of Paeonia lactiflora petal flavonoid extract(PPF). The UH... Flavonoids have attracted considerable attention due to their health benefits. This study aimed to investigate the flavonoid profiles and antioxidant activity of Paeonia lactiflora petal flavonoid extract(PPF). The UHPLC-ESI-Q-Exactive HF MS/MS method was established for characterization, and 21 predominant flavonoid compounds were tentatively identified in PPF. Among them, isoscutellarein-7-(6’-acetylallosyl-(1->2)-glucoside) and scutellarin methylester were discovered in PPF for the first time. Pretreatment with PPF significantly reduced H2O2-induced cell damage, ROS accumulation, and malondialdehyde content and increased the activity of SOD, CAT, and GSH-Px in buffalo rat liver 3A(BRL3A) cells. Moreover, the expression of nuclear Factor E2-related factor(Nrf2) was upregulated by PPF, whose expression trend was consistent with that of heme oxygenase-1(HO-1), glutamate-cysteine ligase catalytic subunit(GCLC), and NAD(P)H quinone oxidoreductase-1(NQO1). These findings suggested that herbaceous peony flavonoids can be used as a natural bioactive agent to prevent oxidative stress. 展开更多
关键词 Antioxidant activity Flavonoid Herbaceous peony petal Oxidative stress Solid-phase extraction
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PoWRKY71 is involved in Paeonia ostii resistance to drought stress by directly regulating light-harvesting chlorophyll a/b-binding 151 gene
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作者 Yuting Luan Zijie Chen +3 位作者 Ziwen Fang Xingqi Huang Daqiu Zhao jun tao 《Horticulture Research》 SCIE CSCD 2023年第11期1-12,共12页
Although the functions of WRKY transcription factors in drought resistance are well known,their regulatory mechanisms in response to drought by stabilising photosynthesis remain unclear.Here,a differentially expressed... Although the functions of WRKY transcription factors in drought resistance are well known,their regulatory mechanisms in response to drought by stabilising photosynthesis remain unclear.Here,a differentially expressed PoWRKY71 gene that was highly expressed in drought-treated Paeonia ostii leaves was identified through transcriptome analysis.PoWRKY71 positively responded to drought stress with significantly enhanced expression patterns and overexpressing PoWRKY71 in tobacco greatly improved plant tolerance to drought stress,whereas silencing PoWRKY71 in P.ostii resulted in a drought-intolerant phenotype.Furthermore,lower chlorophyll contents,photosynthesis,and inhibited expression of photosynthesis-related light-harvesting chlorophyll a/b-binding 151(CAB151)gene were found in PoWRKY71-silenced P.ostii.Meanwhile,a homologous system indicated that drought treatment increased PoCAB151 promoter activity.Interactive assays revealed that PoWRKY71 directly bound on the W-box element of PoCAB151 promoter and activated its transcription.In addition,PoCAB151 overexpressing plants demonstrated increased drought tolerance,together with significantly higher chlorophyll contents and photosynthesis,whereas these indices were dramatically lower in PoCAB151-silenced P.ostii.The above results indicated that PoWRKY71 activated the expression of PoCAB151,thus stabilising photosynthesis via regulating chloroplast homeostasis and chlorophyll content in P.ostii under drought stress.This study reveals a novel drought-resistancemechanism in plants and provides a feasible strategy for improving plant drought resistance via stabilising photosynthesis. 展开更多
关键词 HARVESTING DROUGHT RESISTANCE
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Selection of Stable Reference Genes for Quantitative Real-Time PCR on Herbaceous Peony (Paeonia lactiflora Pall.) in Response to Drought Stress
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作者 Zhipeng Sheng Yuting Luan +2 位作者 Cong Xu jun tao Daqiu Zhao 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第3期801-814,共14页
Herbaceous peony(Paeonia lactiflora Pall.),as a high-end cut flower in the international market,has high ornamental and medicinal values.But in Northern China,drought is a major environmental factor influencing the gr... Herbaceous peony(Paeonia lactiflora Pall.),as a high-end cut flower in the international market,has high ornamental and medicinal values.But in Northern China,drought is a major environmental factor influencing the growth and development of P.lactiflora.Quantitative real-time polymerase chain reaction(qRT-PCR)can evaluate gene expression levels under different stress conditions,and stable internal reference is the key for qRT-PCR.At present,there is no systematic screening of internal reference for correcting gene expressions of P.lactiflora in response to drought stress.In this study,10 candidate genes[ubiquitin(UBQ2),UBQ1,elongation factor 1-α(EF-1α),Histidine(His),eukaryotic initiation factor(eIF),tubulin(TUB),actin(ACT),UBQ3,ACT2,RNA polymerase II(RNA Pol II)]were chosen,and 4 analysis methods were used to compare the stabilities for these 10 genes coping with drought stress.Due to the difference of operation methods,the results of different analysis were distinct,and the final comprehensive analysis indicated that EF-1αwas a relatively stable internal reference gene for P.lactiflora under drought stress.Also,UBQ1 and UBQ2 were the best reference gene combination according to GeNorm analysis.This study will lay a foundation for screening the key genes of P.lactiflora in response to drought stress. 展开更多
关键词 Herbaceous peony QRT-PCR reference gene drought stress
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Osmotic Regulation,Antioxidant Enzyme Activities and Photosynthetic Characteristics of Tree Peony(Paeonia suffruticosa Andr.)in Response to High-Temperature Stress
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作者 Zhipeng Sheng Jiasong Meng +1 位作者 jun tao Daqiu Zhao 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第11期3133-3147,共15页
Tree peony(Paeonia suffruticosa Andr.)is a traditional Chinese flower,which prefers cool weather.However,high temperature in summer in the middle and lower reaches of the Yangtze River restricts its growth and develop... Tree peony(Paeonia suffruticosa Andr.)is a traditional Chinese flower,which prefers cool weather.However,high temperature in summer in the middle and lower reaches of the Yangtze River restricts its growth and development.In this study,osmotic regulation,antioxidant enzyme activities,and photosynthetic characteristics of tree peony in response to high-temperature stress were investigated.The results showed that high-temperature stress had destroyed the cell membrane,manifested as the increased relative electrical conductivity and malondialdehyde content.Moreover,high-temperature stress led to excessive accumulation of reactive oxygen species,thereby,activating antioxidant enzyme activities.Also,photosynthetic parameters and chlorophyll fluorescence parameters directly reflected the damage to the photosystem II reflection center under high-temperature stress.In addition,high-temperature stress led to stomatal closure and chloroplast damage.This study revealed the physiological responses of tree peony to high-temperature stress,laying a foundation for the promotion of tree peony in high-temperature areas and the improvement of high-temperature resistance. 展开更多
关键词 Tree peony high-temperature stress antioxidant enzyme photosynthetic characteristics
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基于超级电容储能型MMC的控制策略 被引量:12
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作者 李磊 陶骏 +1 位作者 朱明星 樊渊 《中国电力》 CSCD 北大核心 2020年第11期15-22,共8页
新能源并网以及冲击性负荷接入易引发电网功率波动,会对邻近发电机组及电力系统的安全稳定构成威胁,为此提出一种基于超级电容器储能型模块化多电平变换器(modular multilevel converter,MMC)的分布式储能系统,利用双向DC/DC变换器控制... 新能源并网以及冲击性负荷接入易引发电网功率波动,会对邻近发电机组及电力系统的安全稳定构成威胁,为此提出一种基于超级电容器储能型模块化多电平变换器(modular multilevel converter,MMC)的分布式储能系统,利用双向DC/DC变换器控制储能系统的充放电过程,并给出相应参数设计原则。采用了基于双闭环PI调节和移相PWM调制技术的控制策略,控制超级电容能量均衡和MMC级联子模块电容电压稳定,引入能量管理机制控制MMC和DC/DC变换器的协同运行,实现了对中、高压系统中冲击性有功变化率的实时补偿。搭建了Matlab/Simulink模型,仿真结果验证了该装置及控制策略的有效性。 展开更多
关键词 超级电容储能 MMC 双向DC/DC变换器 有功冲击 实时补偿
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Prostate cancer risk and aggressiveness associated with the CYPIB1 4326C/G (Leu432Val) polymorphism: a meta-analysis of 2788 cases and 2968 controls 被引量:5
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作者 Jie Yang Dong-Liang Xu +6 位作者 Qiang Lu Zhi-Jian Han jun tao Pei Lu Chao Wang Xiao-Ke Di Min Gu 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第4期560-565,共6页
To derive a precise estimation of the associations between the cytochrome P450 1B 1 (CYPIB1) 4326C/G variants and prostate cancer (PCa) risk or aggressiveness, a meta-analysis was performed using all eligible publ... To derive a precise estimation of the associations between the cytochrome P450 1B 1 (CYPIB1) 4326C/G variants and prostate cancer (PCa) risk or aggressiveness, a meta-analysis was performed using all eligible published studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association in seven literature studies with 2788 cases and 2968 controls. In the overall analysis, no significant association was found between the CYPIB1 4326C/G polymorphism and PCa risk, but ethnicity subgroup analyses and a case-source analysis revealed significant associations. The 4326G allele showed a significant association with increased PCa risk in Asians (OR= 1.52, 95% Ch 1.20-1.92), and significant associations were also observed in a heterozygote comparison (OR= 1.40, 95% Ch 1.03-1.89), a homozygote comparison (0R=2.38, 95% Ch 1.31-4.33) and in a dominant genetic model (OR = 1.52, 95% Ch 1.14-2.01). Moreover, the 4326G allele was also significantly correlated with an increased risk of sporadic PCa (OR= 1.13, 95% Ch 1.04-1.24), and significant associations were observed in a heterozygote comparison (OR= 1.16, 95% Ch 1.02-1.33), a homozygote comparison (OR= 1.24, 95% Ch 1.03-1.49) and a dominant genetic model (OR= 1.19, 95% Ch 1.05- 1.34). The overall analyses and all subgroup analyses showed no significant association between the 4326C/G polymorphism and PCa aggressiveness. Our meta-analysis showed that CYPIB1 4326G allele is significantly associated with an increased PCa risk in Asians and in sporadic PCa cases. 展开更多
关键词 AGGRESSIVENESS CYPIB1 META-ANALYSIS POLYMORPHISM prostate cancer risk
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Theoretical calculation and experimental study on the interaction mechanism between TKX-50 and AP 被引量:6
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作者 jun tao Xiao-Feng Wang +1 位作者 Kun Zhang Xue-song Feng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第4期825-833,共9页
The combination of 5,5'-bistetrazole-1,1'-diolate(TKX-50) and ammonium perchlorate(AP) can make greater use of the chemical energy of TKX-50 based energetic materials.The research on the interaction mechanism ... The combination of 5,5'-bistetrazole-1,1'-diolate(TKX-50) and ammonium perchlorate(AP) can make greater use of the chemical energy of TKX-50 based energetic materials.The research on the interaction mechanism between TKX-50 and AP is very important for designing TKX-50-AP compounds and judging the formation feasibility of composite particles,which can lay a theoretical foundation for the preparation of TKX-50-AP mixed crystals and the application of TKX-50 in propellant,propellant and explosive.Herein,in order to research the interaction mechanism between TKX-50 and AP,density-functional theory calculation was applied to optimize three configurations of TKX-50-AP compounds.The geometry structure,electrostatic potential and binding energy of the compounds were predicted,and the electronic density topological analysis was also carried out.Then TKX-50-AP mixed crystals structures were constructed,and the radial distribution function of H-O and H-N in mixed crystals was calculated.Finally,solvent/non-solvent method was applied to prepare TKX-50-AP composites,and the infrared spectro scopy and the non-isothermal decomposition perfo rmance of the composites were characterized.Results show that the superposition of positive charges in TKX-50 molecule and negative charges in AP makes the electrostatic potential distributions of TKX-50-AP compounds different from that of TKX-50 and AP.The interaction energies of TKX-50-AP 1,TKX-50-AP 2 and TKX-50-AP 3 are 39.743 kJ/mol,61.206 kJ/mol and 27.702 kJ/mol,respectively.The interaction between TKX-50 molecules and AP molecules in TKX-50-AP mixed crystals both depends on hydrogen bonds and van der Waals force,and the number and strength of hydrogen bonds are significantly greater than that of van der Waals force.The composition of AP and TKX-50 makes the absorption peak of the five-membered rings and NH_3 OH^+ of TKX-50 shift to low wavenumber in the infrared spectroscopy.In general,TKX-50 interacts with AP via hydrogen bonds and van der Waals force,and the calculated results are in good agreement with the experimental results.The composition of TKX-50 and AP can also prolong the decomposition process. 展开更多
关键词 5 5'-bistetrazole-1 1'-diolate Ammonium perchlorate Density-functional theory Molecular dynamics Hydrogen bond
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Effect of heating time on bonding interface, atom diffusion and mechanical properties of dissimilar titanium joints produced by thermal self-compressing bonding 被引量:7
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作者 Yun-hua DENG Qiao GUAN jun tao 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第4期662-668,共7页
Solid-state bonding between pure titanium and Ti6Al4V(TC4)alloy was conducted by a new bonding method named as rigid restraint thermal self-compressing bonding.Effects of heating time on bonding interface,atom diffusi... Solid-state bonding between pure titanium and Ti6Al4V(TC4)alloy was conducted by a new bonding method named as rigid restraint thermal self-compressing bonding.Effects of heating time on bonding interface,atom diffusion and mechanical properties of the joints were studied.Results show that atom diffusion between pure titanium and TC4 alloy significantly takes place during bonding.The diffusion depths of Al and V in pure titanium side are increased with increasing heating time.Due to the enhancement of atom diffusion,bond quality of the bonding interface is improved along with the increase of heating time.The heating time seems to have little effect on microhardness distribution across the joint.However,the tensile strength and ductility of the joint have close relation to heating time.Prolonging heating time can improve the tensile strength and ductility of the joint,especially the latter.When the heating time increases to 450 s,solid-state joint with good combination of strength and ductility is attained. 展开更多
关键词 dissimilar titanium alloys joining rigid restraint thermal self-compressing bonding atom diffusion mechanical properties
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Numerical Study on the Stress–Strain Cycle of Thermal Self-Compressing Bonding 被引量:3
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作者 Yun-Hua Deng Qiao Guan +1 位作者 jun tao Bing Wu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第4期140-147,共8页
Thermal self-compressing bonding(TSCB) is a new solid-state bonding method pioneered by the authors. With electron beam as the non-melted heat source, previous experimental study performed on titanium alloys has prove... Thermal self-compressing bonding(TSCB) is a new solid-state bonding method pioneered by the authors. With electron beam as the non-melted heat source, previous experimental study performed on titanium alloys has proved the feasibility of TSCB. However, the thermal stress–strain process during bonding, which is of very important significance in revealing the mechanism of TSCB, was not analysed. In this paper, finite element analysis method is adopted to numerically study the thermal elasto-plastic stress–strain cycle of thermal self-compressing bonding. It is found that due to the localized heating, a non-uniform temperature distribution is formed during bonding, with the highest temperature existed on the bond interface. The expansion of high temperature materials adjacent to the bond interface are restrained by surrounding cool materials and rigid restraints, and thus an internal elasto-plastic stress–strain field is developed by itself which makes the bond interface subjected to thermal compressive action. This thermal self-compressing action combined with the high temperature on the bond interface promotes the atom diffusion across the bond interface to produce solid-state joints. Due to the relatively large plastic deformation, rigid restraint TSCB obtains sound joints in relatively short time compared to diffusion bonding. 展开更多
关键词 Thermal self-compressing bonding Locally non-melted heating Thermal elasto-plastic stress–strain Atom diffusion Solid-state bonding Finite element analysis
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EGTA reduces the inflorescence stem mechanical strength of herbaceous peony by modifying secondary wall biosynthesis 被引量:5
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作者 Yuhan Tang Daqiu Zhao +1 位作者 Jiasong Meng jun tao 《Horticulture Research》 SCIE 2019年第1期1302-1314,共13页
The mechanical strength of inflorescence stems is an important trait in cut flowers.Calcium ions(Ca^(2+))play a pivotal role in maintaining stem strength,but little is known about the underlying molecular mechanisms.I... The mechanical strength of inflorescence stems is an important trait in cut flowers.Calcium ions(Ca^(2+))play a pivotal role in maintaining stem strength,but little is known about the underlying molecular mechanisms.In this study,we treated herbaceous peony(Paeonia lactiflora Pall.)with ethyl glycol tetraacetic acid(EGTA),an effective Ca^(2+)chelator,and used morphology indicators,spectroscopic analysis,histochemical staining,electron microscopy,and proteomic techniques to investigate the role of Ca^(2+)in inflorescence stem mechanical strength.The EGTA treatment reduced the mechanical strength of inflorescence stems,triggered the loss of Ca^(2+)from cell walls,and reduced lignin in thickened secondary walls in xylem cells as determined by spectroscopic analysis and histochemical staining.Electron microscopy showed that the EGTA treatment also resulted in significantly fewer xylem cell layers with thickened secondary walls as well as in reducing the thickness of these secondary walls.The proteomic analysis showed 1065 differentially expressed proteins(DEPs)at the full-flowering stage(S4).By overlapping the Kyoto encyclopedia of genes and genomes(KEGG)and gene ontology(GO)analysis results,we identified 43 DEPs involved in signal transduction,transport,energy metabolism,carbohydrate metabolism,and secondary metabolite biosynthesis.Using quantitative real-time polymerase chain reaction(qRT-PCR)analysis,we showed that EGTA treatment inhibited Ca^(2+)sensors and secondary wall biosynthesis-related genes.Our findings revealed that EGTA treatment reduced the inflorescence stem mechanical strength by reducing lignin deposition in xylem cells through altering the expression of genes involved in Ca^(2+)binding and secondary wall biosynthesis. 展开更多
关键词 metabolism herba inhibited
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血清PDGF-BB作为糖尿病视网膜病变生物标志物的研究 被引量:4
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作者 陈冉 王应利 +2 位作者 周玉梅 陶俊 靳扬扬 《国际眼科杂志》 CAS 北大核心 2019年第5期853-856,共4页
目的:研究血清中血小板源性生长因子-BB(PDGF-BB)的水平与2型糖尿病患者DR的相关性。方法:以健康体检者为对照组(75例),糖尿病病例组分为NDR 25例、NPDR 25例和PDR 25例。用ELISA测定各组样本血清中PDGF-BB水平,并分析血清PDGF-BB与糖... 目的:研究血清中血小板源性生长因子-BB(PDGF-BB)的水平与2型糖尿病患者DR的相关性。方法:以健康体检者为对照组(75例),糖尿病病例组分为NDR 25例、NPDR 25例和PDR 25例。用ELISA测定各组样本血清中PDGF-BB水平,并分析血清PDGF-BB与糖尿病病程、HbA1c等各项生化指标的关系,分析PDGF-BB与黄斑厚度的关系。结果:对照组、NDR组、NPDR组、PDR组血清PDGF-BB水平各组间均有差异(F=14.259,P<0.01)。NPDR组、PDR组血清PDGF-BB水平(535.67±69.21、551.60±103.46pg/mL)均高于对照组、NDR组(400.28±44.55、409.65±50.37pg/mL)。多元回归分析血清PDGF-BB水平与空腹血糖(FPG)、甘油三酯(TG)、糖尿病病程有相关性(均P<0.05)。PDR组血清PDGF-BB水平与黄斑厚度存在相关性(r=0.613,P<0.05),对照组、NDR组、NPDR组血清PDGF-BB水平与黄斑厚度无相关性(r=0.013、0.051、0.062,均P>0.05)。结论:血清PDGF-BB水平随着DR病变程度加重而升高,与黄斑水肿存在相关性,并与FPG、TG、糖尿病病程有相关性,可以考虑作为DR的生物学标志物。 展开更多
关键词 糖尿病视网膜病变 血小板源性生长因子-BB 黄斑厚度
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Simultaneous optical g, r, i monitoring and IDV periodic analysis for quasar 3C 454.3 被引量:2
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作者 jun-Hui Fan Yu-Hai Yuan +3 位作者 Hong Wu Feng Wang jun tao Min-Feng Gu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第10期43-50,共8页
With the 1.26 m National Astronomical Observatory-Guangzhou University Infrared/Optical Telescope(NAGIOT) at Xinglong Station of National Astronomical Observatories, Chinese Academy of Sciences, we obtained 419 groups... With the 1.26 m National Astronomical Observatory-Guangzhou University Infrared/Optical Telescope(NAGIOT) at Xinglong Station of National Astronomical Observatories, Chinese Academy of Sciences, we obtained 419 groups of simultaneous observations at g, r and i bands, for the first time,targeting quasar 3 C 454.3 during 15 nights from 2016 October 23 to 2016 December 15. Based on our observations, we investigate the optical variabilities, the relation between brightness and color index, and the periodicity variability. The presented analyses demonstrate that: 1. The maximum variations at the g, r and i bands are △mg|max= 1.015 ± 0.042 mag,△mr|max= 1.188 ± 0.050 mag and △mi|max= 1.305 ± 0.057 mag respectively. 2. During our 15 night monitoring program, intra-day variability was detected on one night(Nov. 2). Also, the brightness increased by A = 15.86% over 50.8 min,then decreased by A = 22.42% over 40.1 min. After a small bright state, its brightness increased again by18.1% over 55 min at the g band. Similar phenomena happened at r and i bands. The intra-day variabilities at the three bands on 2016 November 2 indicate a period of 105 min, which implies a black hole mass of MBH =(0.3 ~ 1.85)× 10^9 M⊙. 3. There is an anti-correlation between color index and magnitude,suggesting the source becomes redder when it brightens. 展开更多
关键词 GALAXIES QUASARS INDIVIDUAL (3C 454.3)
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Effects of High-Temperature Stress on Photosynthetic Characteristics and Antioxidant Enzyme System of Paeonia ostii 被引量:3
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作者 Xiaoxiao Wang Ziwen Fang +1 位作者 Daqiu Zhao jun tao 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第3期599-615,共17页
Paeonia ostii is an economically important oil crop,which has been widely cultivated in the middle and lower reaches of the Yangtze River in China in recent years.Although P.ostii is highly adaptable to the environmen... Paeonia ostii is an economically important oil crop,which has been widely cultivated in the middle and lower reaches of the Yangtze River in China in recent years.Although P.ostii is highly adaptable to the environment,the prolonged high summer temperature in this region severely inhibits its growth,which adversely affects seed yield and quality.In this study,P.ostii plants were subjected to 20℃/15℃(day/night)and 40℃/35℃(day/night)temperatures for 15 days.The changes in physiological and biochemical indicators of P.ostii under high-temperature stress were initially investigated.The results showed that with the deepening of leaf etiolation,chlorophyll a and chlorophyll b concentration,carotenoid concentration,Soil Plant Analysis Development(SPAD)values and leaf relative water content decreased significantly,while both relative electrical conductivity(REC)and free proline concentration showed an upward trend.Meanwhile,the continuous accumulation of reactive oxygen species(ROS)in P.ostii plants,led to an increased activity of antioxidant enzymes including superoxide dismutase(SOD),peroxidase(POD),catalase(CAT)and ascorbate peroxidase(APX).Moreover,with the extension of the high-temperature treatment,the anatomical structures of P.ostii were destroyed,resulting in a decreased photochemical efficiency of the photosystem II(PSII)reaction center and photosynthesis was inhibited.Taken together,these results provide reference values for understanding the physiological response of P.ostii to hightemperature stress and establish a foundation for further research on the relevant underlying molecular mechanisms. 展开更多
关键词 Antioxidant enzymes membrane damage PHOTOSYNTHESIS reactive oxygen species
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Lignin provides mechanical support to herbaceous peony(Paeonia lactiflora Pall.)stems 被引量:2
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作者 Daqiu Zhao Yuting Luan +3 位作者 Xing Xia Wenbo Shi Yuhan Tang jun tao 《Horticulture Research》 SCIE 2020年第1期14-28,共15页
Stem bending caused by mechanical failure is a major constraint for high-quality herbaceous peony(Paeonia lactiflora Pall.)cut flowers,but little is known about the underlying factors.In this study,two P.lactiflora cu... Stem bending caused by mechanical failure is a major constraint for high-quality herbaceous peony(Paeonia lactiflora Pall.)cut flowers,but little is known about the underlying factors.In this study,two P.lactiflora cultivars,Xixia Yingxue(bending)and Hong Feng(upright),were used to investigate differences in stem bending.The results showed that the stem mechanical strength of Hong Feng was significantly higher than that of Xixia Yingxue,and the thickening of the secondary cell wall and the number of thickened secondary cell wall layers in Hong Feng were significantly higher than those in Xixia Yingxue.Moreover,compared with Xixia Yingxue,Hong Feng showed greater lignification of the cell wall and lignin deposition in the cell walls of the sclerenchyma,vascular bundle sheath and duct.All three types of lignin monomers were detected.The S-lignin,G-lignin,and total lignin contents and the activities of several lignin biosynthesis-related enzymes were higher in Hong Feng than in the other cultivar,and the S-lignin content was closely correlated with stem mechanical strength.In addition,113,974 full-length isoforms with an average read length of 2106 bp were obtained from the full-length transcriptome of P.lactiflora stems,and differential expression analysis was performed based on the comparative transcriptomes of these two cultivars.Ten lignin biosynthesis-related genes,including 26 members that were closely associated with lignin content,were identified,and multiple upregulated and downregulated transcription factors were found to positively or negatively regulate lignin biosynthesis.Consequently,lignin was shown to provide mechanical support to P.lactiflora stems,providing useful information for understanding the formation of P.lactiflora stem strength. 展开更多
关键词 strength FLOWERS CULTIVAR
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Central retinal artery occlusion after endovascular coil embolization for internal carotid artery aneurysm 被引量:1
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作者 Ying-Li Wang Yan-Nian Hui +3 位作者 Ran Chen Yang-Yang Jin jun tao Yu-Mei Zhou 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第3期520-522,共3页
Dear Editor,We are writing this letter to report an unexpected rare caseofcentralretinalarteryocclusion(CRAO)happened after stent-assisted coiling for internal carotid artery(ICA)aneurysm in a female patient.CRAO is a... Dear Editor,We are writing this letter to report an unexpected rare caseofcentralretinalarteryocclusion(CRAO)happened after stent-assisted coiling for internal carotid artery(ICA)aneurysm in a female patient.CRAO is a devastating ocular emergency with poor visual prognosis and no universal acceptedtreatmentatpresent.CRAOisusuallyassociated witharterialhypertension,diabetesmellitus,renaldisease. 展开更多
关键词 Figure Central retinal ARTERY occlusion AFTER ENDOVASCULAR coil EMBOLIZATION for internal CAROTID ARTERY ANEURYSM ICA FFA
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Compact Coplanar Epsilon-Negative Antenna with Ultra-Wide Band Character 被引量:1
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作者 jun tao Quanyuan Feng Zongliang Zheng 《China Communications》 SCIE CSCD 2017年第2期49-56,共8页
In this paper, a compact coplanar epsilon.negative(ENG) antenna is proposed with ultra.wide operation band and small size of 18×11.5 mm2. The proposed antenna is designed based on a coplanar.waveguide(CPW) feedin... In this paper, a compact coplanar epsilon.negative(ENG) antenna is proposed with ultra.wide operation band and small size of 18×11.5 mm2. The proposed antenna is designed based on a coplanar.waveguide(CPW) feeding antenna, and thus the via.free structure is employed to realize the ENG unit cell, which is convenient to tune the frequency of zeroth.order resonance(ZOR) and extends the ZOR bandwidth. The high.order resonant frequencies are achieved and mainly determined by the separate slots that are located between the radiating patch and the ground plane. Adding the left.handed inductance between the radiating patch and ground has slight impact on the high.order resonant frequencies, and then the ultra.wide band is achieved by merging the ZOR bandwidth with the high.order resonant bandwidths. The ground plane primarily works as a matching network for the proposed antenna. Although it generates a low.frequency resonance, the performance is undesirable due to the impedance mismatching. The measured results show that the reflection coefficient, |S11| <.10 d B, is in a wide frequency range from 5.25 to 13 GHz, which covers the upper operation band of UWB communication. Also, the antenna contains relatively stable gains and omni.directional radiation patterns. 展开更多
关键词 ENG antenna CPW ZOR bandwidth merging ultra-wide band
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