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温度和疲劳共同作用对溴化丁基橡胶气体阻隔性能的影响
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作者 张帆 张力伟 +1 位作者 熊英 郭少云 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第2期134-140,共7页
溴化丁基橡胶(BIIR)因其出色的气体阻隔性能成为轮胎内衬层首选材料,但轮胎使用过程中因摩擦生热产生的高温和滚动过程中的屈挠疲劳作用,其性能和使用寿命将会受到很大的影响,因此,探索温度和疲劳作用对BIIR气体阻隔性能的影响具有重要... 溴化丁基橡胶(BIIR)因其出色的气体阻隔性能成为轮胎内衬层首选材料,但轮胎使用过程中因摩擦生热产生的高温和滚动过程中的屈挠疲劳作用,其性能和使用寿命将会受到很大的影响,因此,探索温度和疲劳作用对BIIR气体阻隔性能的影响具有重要意义。文中对比研究了温度和屈挠疲劳单因素作用以及双因素作用下,BIIR气体阻隔性能的变化情况;通过交联密度测试、动态力学热分析及透射电镜等手段,探寻了BIIR在温度和疲劳双因素作用下其分子交联网络和填料分布情况的变化。结果表明,热老化作用使BIIR交联度增加,气体阻隔性能提高;疲劳作用对其气体阻隔性能的影响也较小;但温度和疲劳共同作用下,BIIR在较高温度下形成的交联网络又经屈挠疲劳的作用,更易发生裂解,并带动填料粒子的“移动”,导致了BIIR橡胶气体阻隔性能的大幅降低。 展开更多
关键词 溴化丁基橡胶 热老化 屈挠疲劳 气体阻隔性能
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挤压比对双相Mg-8Li-6Zn-2Gd合金显微组织、织构和力学性能的影响
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作者 孙月花 张帆 +2 位作者 杨滨 任建 宋广生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第3期833-845,共13页
通过显微组织观察、织构分析和拉伸测试等手段研究挤压比对双相Mg-8Li-6Zn-2Gd合金显微组织、织构和力学性能的影响。结果表明:均匀化态Mg-8Li-6Zn-2Gd合金中含有α-Mg、β-Li、Mg Li Zn、I相和W相。经热挤压后,共晶I相被碾碎成细小颗粒... 通过显微组织观察、织构分析和拉伸测试等手段研究挤压比对双相Mg-8Li-6Zn-2Gd合金显微组织、织构和力学性能的影响。结果表明:均匀化态Mg-8Li-6Zn-2Gd合金中含有α-Mg、β-Li、Mg Li Zn、I相和W相。经热挤压后,共晶I相被碾碎成细小颗粒状,而W相保持原有块状形状。合金中α-Mg基体和β-Li基体在热挤压过程中均发生了动态再结晶(DRX),且晶粒随着挤压比的增加逐渐细化。经热挤压后,α-Mg基体的基面织构弱化和柱面织构增强是由于非基面滑移的激活;β-Li基体中形成明显的α和γ纤维织构主要与动态回复与动态再结晶相关。热挤压同时提升Mg-8Li-6Zn-2Gd合金的抗拉强度和伸长率,并在挤压比为16:1时获得最佳的综合力学性能。 展开更多
关键词 MG-LI合金 二十面体准晶相 挤压比 动态再结晶 宏观织构 力学性能
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Artificial selection of the Green Revolution gene Semidwarf 1 is implicated in upland rice breeding
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作者 Shuliang Jiao Qinyan Li +6 位作者 fan zhang Yonghong Tao Yingzhen Yu fan Yao Qingmao Li Fengyi Hu Liyu Huang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期769-780,共12页
Semidwarf breeding has boosted crop production and is a well-known outcome from the first Green Revolution. The Green Revolution gene Semidwarf 1(SD1), which modulates gibberellic acid(GA) biosynthesis, plays a princi... Semidwarf breeding has boosted crop production and is a well-known outcome from the first Green Revolution. The Green Revolution gene Semidwarf 1(SD1), which modulates gibberellic acid(GA) biosynthesis, plays a principal role in determining rice plant height. Mutations in SD1 reduce rice plant height and promote lodging resistance and fertilizer tolerance to increase grain production. The plant height mediated by SD1 also favors grain yield under certain conditions. However, it is not yet known whether the function of SD1 in upland rice promotes adaptation and grain production. In this study, the plant height and grain yield of irrigated and upland rice were comparatively analyzed under paddy and dryland conditions. In response to dryland environments, rice requires a reduction in plant height to cope with water deficits. Upland rice accessions had greater plant heights than their irrigated counterparts under both paddy and dryland conditions, and appropriately reducing plant height could improve adaptability to dryland environments and maintain high grain yield formation. Moreover, upland rice cultivars with thicker stem diameters had stronger lodging resistance, which addresses the lodging problem. Knockout of SD1 in the upland rice cultivar IRAT104 reduced the plant height and grain yield, demonstrating that the adjustment of plant height mediated by SD1 could increase grain production in dryland fields. In addition, an SD1 genetic diversity analysis verified that haplotype variation causes phenotypic variation in plant height. During the breeding history of rice, SD1 allelic mutations were selected from landraces to improve the grain yield of irrigated rice cultivars, and this selection was accompanied by a reduction in plant height. Thus, five known mutant alleles were analyzed to verify that functional SD1 is required for upland rice production. All these results suggest that SD1 might have undergone artificial positive selection in upland rice, which provides further insights concerning greater plant height in upland rice breeding. 展开更多
关键词 Green Revolution Semidwarf 1 high-yield breeding upland rice plant height
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AlLi-LDH中Al-O八面体环吸附锂的机制
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作者 田勇攀 王成成 +3 位作者 张帆 徐亮 赵卓 童碧海 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第4期1321-1332,共12页
采用共沉淀法合成铝锂层状双氢氧化物(AlLi-LDH)并进行提锂试验。AlLi-LDH的空间群为P32或C2/m,微观形貌呈直径为5~10μm的规则球形。AlLi-LDH吸附Li^(+)后,空间群转化为P32。当Li^(+)浓度为95.4 mg/L时,1 h后锂吸附量为8.98 mg/g;吸附4... 采用共沉淀法合成铝锂层状双氢氧化物(AlLi-LDH)并进行提锂试验。AlLi-LDH的空间群为P32或C2/m,微观形貌呈直径为5~10μm的规则球形。AlLi-LDH吸附Li^(+)后,空间群转化为P32。当Li^(+)浓度为95.4 mg/L时,1 h后锂吸附量为8.98 mg/g;吸附48 h后,吸附量增加到16.50 mg/g;根据二级吸附模型预测Li^(+)吸附总量为17.57 mg/g。当Mg^(2+)/Li^(+)的质量比为1067时,Mg^(2+)/Li^(+)分离系数为29536。空间群为P32时,Li-O的相互作用强度变弱,且相互作用属于静电效应。具有P32空间基团的AlLi-LDH更容易吸附和解吸Li^(+)。 展开更多
关键词 共沉淀 铝锂层状双氢氧化物 空间群 吸附
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Pachymic acid exerts antitumor activities by modulating the Wnt/β-catenin signaling pathway via targeting PTP1B
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作者 Hao zhang Kun Zhu +5 位作者 Xue-Feng zhang Yi-Hui Ding Bing Zhu Wen Meng Qing-Song Ding fan zhang 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第4期170-180,共11页
Objective:To determine the inhibitory effects of pachymic acid on lung adenocarcinoma(LUAD)cells and elucidate its underlying mechanism.Methods:CCK-8,wound healing,Transwell,Western blot,tube formation,and immunofluor... Objective:To determine the inhibitory effects of pachymic acid on lung adenocarcinoma(LUAD)cells and elucidate its underlying mechanism.Methods:CCK-8,wound healing,Transwell,Western blot,tube formation,and immunofluorescence assays were carried out to measure the effects of various concentrations of pachymic acid on LUAD cell proliferation,metastasis,angiogenesis as well as autophagy.Subsequently,molecular docking technology was used to detect the potential targeted binding association between pachymic acid and protein tyrosine phosphatase 1B(PTP1B).Moreover,PTP1B was overexpressed in A549 cells to detect the specific mechanisms of pachymic acid.Results:Pachymic acid suppressed LUAD cell viability,metastasis as well as angiogenesis while inducing cell autophagy.It also targeted PTP1B and lowered PTP1B expression.However,PTP1B overexpression reversed the effects of pachymic acid on metastasis,angiogenesis,and autophagy as well as the expression of Wnt3a andβ-catenin in LUAD cells.Conclusions:Pachymic acid inhibits metastasis and angiogenesis,and promotes autophagy in LUAD cells by modulating the Wnt/β-catenin signaling pathway via targeting PTP1B. 展开更多
关键词 Pachymic acid Lung adenocarcinoma Protein tyrosine phosphatase 1B Wnt/β-catenin signaling pathway METASTASIS ANGIOGENESIS AUTOPHAGY
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Controllable step-flow growth of GaN on patterned freestanding substrate
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作者 Peng Wu Jianping Liu +7 位作者 Lei Hu Xiaoyu Ren Aiqin Tian Wei Zhou fan zhang Xuan Li Masao Ikeda Hui Yang 《Journal of Semiconductors》 EI CAS CSCD 2024年第2期46-50,共5页
A new kind of step-flow growth mode is proposed,which adopts sidewall as step source on patterned GaN substrate.The terrace width of steps originated from the sidewall was found to change with the growth temperature a... A new kind of step-flow growth mode is proposed,which adopts sidewall as step source on patterned GaN substrate.The terrace width of steps originated from the sidewall was found to change with the growth temperature and ammonia flux.The growth mechanism is explained and simulated based on step motion model.This work helps better understand the behaviors of step advancement and puts forward a method of precisely modulating atomic steps. 展开更多
关键词 step-flow growth GAN terrace width step motion
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Electrical properties and structural optimization of GaN/InGaN/GaN tunnel junctions grown by molecular beam epitaxy
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作者 Jun fang fan zhang +4 位作者 Wenxian Yang Aiqin Tian Jianping Liu Shulong Lu Hui Yang 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期48-54,共7页
The InGaN films and GaN/InGaN/GaN tunnel junctions(TJs)were grown on GaN templates with plasma-assisted molecular beam epitaxy.As the In content increases,the quality of InGaN films grown on GaN templates decreases an... The InGaN films and GaN/InGaN/GaN tunnel junctions(TJs)were grown on GaN templates with plasma-assisted molecular beam epitaxy.As the In content increases,the quality of InGaN films grown on GaN templates decreases and the surface roughness of the samples increases.V-pits and trench defects were not found in the AFM images.p++-GaN/InGaN/n++-GaN TJs were investigated for various In content,InGaN thicknesses and doping concentration in the InGaN insert layer.The InGaN insert layer can promote good interband tunneling in GaN/InGaN/GaN TJ and significantly reduce operating voltage when doping is sufficiently high.The current density increases with increasing In content for the 3 nm InGaN insert layer,which is achieved by reducing the depletion zone width and the height of the potential barrier.At a forward current density of 500 A/cm^(2),the measured voltage was 4.31 V and the differential resistance was measured to be 3.75×10^(−3)Ω·cm^(2)for the device with a 3 nm p++-In_(0.35)Ga_(0.65)N insert layer.When the thickness of the In_(0.35)Ga_(0.65)N layer is closer to the“balanced”thickness,the TJ current density is higher.If the thickness is too high or too low,the width of the depletion zone will increase and the current density will decrease.The undoped InGaN layer has a better performance than n-type doping in the TJ.Polarization-engineered tunnel junctions can enhance the functionality and performance of electronic and optoelectronic devices. 展开更多
关键词 GaN/InGaN/GaN tunnel junctions polarization-engineering molecular beam epitaxy
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Systematic analysis of DNA polymerases as therapeutic targets in pan-cancers
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作者 ZHENHUA LI HUILAI LV +8 位作者 fan zhang ZIMING ZHU QIANG GUO MINGBO WANG CHAO HUANG LIJUAN CHEN WENPAN zhang YUN LI ZIQIANG TIAN 《BIOCELL》 SCIE 2024年第1期123-138,共16页
Introduction:DNA polymerases are crucial for maintaining genome stability and influencing tumorigenesis.However,the clinical implications of DNA polymerases in tumorigenesis and their potential as anti-cancer therapy ... Introduction:DNA polymerases are crucial for maintaining genome stability and influencing tumorigenesis.However,the clinical implications of DNA polymerases in tumorigenesis and their potential as anti-cancer therapy targets are not well understood.Methods:We conducted a systematic analysis using TCGA Pan-Cancer Atlas data and Gene Set Cancer Analysis results to examine the expression profiles of 15 DNA polymerases(POLYs)and their clinical correlations.We also evaluated the prognostic value of POLYs by analyzing their expression levels in relation to overall survival time(OS)using Kaplan-Meier survival curves.Additionally,we investigated the correlations between POLY expression and immune cells,DNA damage repair(DDR)pathways,and ubiquitination.Drug sensitivity analysis was performed to assess the relationship between POLY expression and drug response.Results:Our analysis revealed that 14 out of 15 POLYs exhibited significantly distinct expression patterns between tumor and normal samples across most cancer types,except for DNA nucleotidylexotransferase(DNTT).Specifically,POLD1 and POLE showed elevated expression in almost all cancers,while POLQ exhibited high expression levels in all cancer types.Some POLYs showed heightened expression in specific cancer subtypes,while others exhibited low expression.Kaplan-Meier survival curves demonstrated significant prognostic value of POLYs in multiple cancers,including PAAD,KIRC,and ACC.Cox analysis further validated these findings.Alteration patterns of POLYs varied significantly among different cancer types and were associated with poorer survival outcomes.Significant correlations were observed between the expression of POLY members and immune cells,DDR pathways,and ubiquitination.Drug sensitivity analysis indicated an inverse relationship between POLY expression and drug response.Conclusion:Our comprehensive study highlights the significant role of POLYs in cancer development and identifies them as promising prognostic and immunological biomarkers for various cancer types.Additionally,targeting POLYs therapeutically holds promise for tumor immunotherapy. 展开更多
关键词 DNA polymerases(POLYs) Prognostic biomarker The Cancer Genome Atlas(TCGA) Ubiquitination network
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镍纳米粒子耦合氧空位高效催化转化棕榈酸制备烷烃
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作者 曾严 王慧 +7 位作者 杨惠茹 隽超 李丹 温晓东 张帆 邹吉军 彭冲 胡常伟 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第4期229-242,共14页
随着能源需求的增加和生态环境的恶化,可再生资源的开发与利用越来越受到人们的重视.其中,生物质能源分布广泛,储量丰富,是化石燃料的理想替代品.然而生物质具有高含氧量、高粘度和低热值等特性,开发高效的加氢脱氧催化剂对生物质资源... 随着能源需求的增加和生态环境的恶化,可再生资源的开发与利用越来越受到人们的重视.其中,生物质能源分布广泛,储量丰富,是化石燃料的理想替代品.然而生物质具有高含氧量、高粘度和低热值等特性,开发高效的加氢脱氧催化剂对生物质资源的开发和利用具有重要的应用价值.近年来,研究者们对生物质(脂肪酸及其衍生物)加氢脱氧催化体系进行了大量研究,发现Ni/CeO_(2)基催化剂能够有效地催化生物质转化并获得较高的生物油产率,然而CeO_(2)载体的氧空位含量与Ni纳米颗粒尺寸、催化剂脱氧性能之间的关系仍然不明晰.本文采用水热合成法和沉淀法分别制备了H-CeO_(2)和P-CeO_(2)载体(商用CeO_(2)标记为C-CeO_(2)),通过浸渍法制备了Ni/H-CeO_(2),Ni/P-CeO_(2)和Ni/C-CeO_(2)催化剂,同时采用无氧空位的SiO_(2)做载体制备了Ni/SiO_(2)催化剂,研究了CeO_(2)氧空位含量对Ni纳米粒子尺寸的影响及其与加氢脱氧催化性能之间的关系.EPR结果表明,不同载体上氧空位含量的顺序为H-CeO_(2)>P-CeO_(2)>C-CeO_(2).XRD结果表明,在H-CeO_(2)载体上生成的Ni纳米粒子尺寸最小,分散度最高;在C-CeO_(2)载体上生成的Ni纳米粒子尺寸最大,分散度最差;而在无氧空位的SiO_(2)载体上生成的Ni纳米粒子尺寸明显大于H-CeO_(2)和P-CeO_(2)载体上生成的Ni纳米粒子.XPS结果显示,不同载体上的O表面/(O表面+O晶格)的比值顺序为H-CeO_(2)>P-CeO_(2)>C-CeO_(2),表明H-CeO_(2)载体上具有最高的氧空位含量,C-CeO_(2)载体上氧空位含量最低,与EPR结果一致;Ni/H-CeO_(2),Ni/P-CeO_(2)和Ni/C-CeO_(2)催化剂上氧空位含量顺序与载体一致,但其氧空位含量比纯载体高,说明Ni有利于氧空位的生成.Raman结果表明,Ni/H-CeO_(2)催化剂上具有的氧空位含量最高,Ni/P-CeO_(2)次之,Ni/C-CeO_(2)最差,与XPS结果一致.H2-TPR结果表明,氧空位的存在增强了Ni与CeO_(2)载体的相互作用,有利于Ni的分散.SEM和TEM实验结果也表明了在氧空位含量最高的H-CeO_(2)载体上Ni分散度最高.DFT结果进一步证实了高的氧空位含量增强了金属-载体相互作用,促进了Ni的分散.电荷分析表明,Ni纳米颗粒和CeO_(2)载体之间存在电子转移,在具有丰富氧空位的表面上从Ni转移到CeO_(2)的电子数少于规则表面的电子数,Ni原子将电子转移到载体上,降低了Ni原子的氧化程度.活性结果表明,三种纯载体催化转化棕榈酸的效果均不佳,烷烃选择性均低于5.0%;负载活性组分Ni后,催化性能明显提升.在Ni/C-CeO_(2)催化剂上,棕榈酸的转化率为72.1%,十五烷的选择性为21.9%;Ni/P-CeO_(2)催化剂对棕榈酸的转化率达到99.6%,十五烷的选择性为77.6%;Ni/H-CeO_(2)催化剂具有最佳的催化活性,其催化性能高于大部分文献报道的贵金属催化剂,棕榈酸转化率为100%,十五烷选择性达到94.8%;而在无氧空位的Ni/SiO_(2)催化剂上性能最差,棕榈酸转化率仅为52.9%,得到少量十五烷,也未检测到十六烷,这表明丰富的氧空位在棕榈酸转化过程中发挥了重要作用.结合文献及活性结果分析,丰富的氧空位有利于吸附更多的棕榈酸,从而有利于其转化.通过反应后的XRD及TG测试结果发现,Ni纳米颗粒的尺寸在反应后没有显著变化,表明氧空位也能有效地稳定Ni纳米颗粒尺寸.不同尺寸Ni纳米颗粒的催化剂活性结果表明,在较小尺寸的Ni纳米颗粒催化剂上可以获得更高的十五烷选择性,表明十五烷选择性与Ni纳米颗粒尺寸相关联.综上,Ni/H-CeO_(2)的优异催化性能归因于高氧空位含量和小尺寸Ni纳米颗粒的协同耦合作用. 展开更多
关键词 加氢脱氧 氧空位 Ni纳米粒子 棕榈酸转化 生物燃料
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The complete reference genome for grapevine (Vitis vinifera L.) genetics and breeding 被引量:8
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作者 Xiaoya Shi Shuo Cao +29 位作者 Xu Wang Siyang Huang Yue Wang Zhongjie Liu Wenwen Liu Xiangpeng Leng Yanling Peng Nan Wang Yiwen Wang Zhiyao Ma Xiaodong Xu fan zhang Hui Xue Haixia Zhong Yi Wang Kekun zhang Amandine Velt Komlan Avia Daniela Holtgräwe Jérôme Grimplet JoséTomás Matus Doreen Ware Xinyu Wu Haibo Wang Chonghuai Liu Yuling fang Camille Rustenholz Zongming Cheng Hua Xiao Yongfeng Zhou 《Horticulture Research》 SCIE CSCD 2023年第5期207-219,共13页
Grapevine is one of the most economically important crops worldwide.However,the previous versions of the grapevine reference genome tipically consist of thousands of fragments with missing centromeres and telomeres,li... Grapevine is one of the most economically important crops worldwide.However,the previous versions of the grapevine reference genome tipically consist of thousands of fragments with missing centromeres and telomeres,limiting the accessibility of the repetitive sequences,the centromeric and telomeric regions,and the study of inheritance of important agronomic traits in these regions.Here,we assembled a telomere-to-telomere(T2T)gap-free reference genome for the cultivar PN40024 using PacBio HiFi long reads.The T2T reference genome(PN_T2T)is 69 Mb longer with 9018 more genes identified than the 12X.v0 version.We annotated 67%repetitive sequences,19 centromeres and 36 telomeres,and incorporated gene annotations of previous versions into the PN_T2T assembly.We detected a total of 377 gene clusters,which showed associations with complex traits,such as aroma and disease resistance.Even though PN40024 derives from nine generations of selfing,we still found nine genomic hotspots of heterozygous sites associated with biological processes,such as the oxidation–reduction process and protein phosphorylation.The fully annotated complete reference genome therefore constitutes an important resource for grapevine genetic studies and breeding programs. 展开更多
关键词 BREEDING CROPS CULTIVAR
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Adsorption of rubidium ion from aqueous solution by surface ion imprinted materials 被引量:3
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作者 Zhongqi Ren Jie Wang +3 位作者 Hewei zhang fan zhang Shichao Tian Zhiyong Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期1-10,共10页
A new type of rubidium ion-imprinted polymer has been synthesized by the surface-imprinting technique using methacrylic acid as the functional monomer,the rubidium ion as the template,methanol as the solvent,and silic... A new type of rubidium ion-imprinted polymer has been synthesized by the surface-imprinting technique using methacrylic acid as the functional monomer,the rubidium ion as the template,methanol as the solvent,and silica as a carrier.Ethylene glycol dimethacrylate and 2,2-azobisisobutyronitrile were used as acrosslinker and an initiator,respectively.In addition,based on the macrocyclic effect of crown ethers,the 18-crown-6 ligand was introduced as a ligand to fix the template ions better.Scanning electron microscopy,zeta-potential analysis,Fourier transform infrared spectroscopy,thermogravimetric analysis,and X-ray photoelectron spectroscopy were performed to characterize the ion-imprinted polymer.The effects of the preparation and adsorption conditions on the adsorption performance of the rubidium ion-imprinted polymer were investigated.The results indicated that the rubidium ion-imprinted polymer has high selectivity and faster kinetics than other adsorbents,with an equilibrium adsorption capacity of 200.19 mg·g^(-1)at 298 K within 25 min.The sorption isotherm was well described by the Freundlich isotherm model,while the adsorption kinetics fitted the pseudo-second-order kinetic model.Consecutive adsorption-desorption experiments showed that the ion-imprinted polymer had good chemical stability and reusability. 展开更多
关键词 Surface-imprinted material ADSORPTION Aqueous solution Silica SELECTIVITY
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添加剂及其含量对交联聚乙烯高压电缆绝缘材料性能影响 被引量:2
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作者 侯帅 傅明利 +4 位作者 黎小林 展云鹏 张繁 徐曙 巩俊强 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第2期58-65,共8页
为优化高压电缆交联聚乙烯(XLPE)绝缘材料配方,采用凝胶萃取、热延伸、转矩流变仪和失重法研究材料交联特性,采用红外光谱表征XLPE热氧老化特性,并测试了XLPE的力学性能和电学性能。结果表明,随交联剂过氧化二异丙苯(DCP)含量增大,XLPE... 为优化高压电缆交联聚乙烯(XLPE)绝缘材料配方,采用凝胶萃取、热延伸、转矩流变仪和失重法研究材料交联特性,采用红外光谱表征XLPE热氧老化特性,并测试了XLPE的力学性能和电学性能。结果表明,随交联剂过氧化二异丙苯(DCP)含量增大,XLPE凝胶含量及交联速率增大、力学性能变化较小、交流击穿强度的温度敏感性降低。优先考虑交联特性,确定DCP含量为1.8 phr。随抗氧剂含量增加,XLPE交联度降低、热延伸率稍有提高。相比单独使用0.3 phr抗氧剂300的XLPE,抗氧剂1010和1035各以0.15 phr复配使用可发生协同作用,从而更显著地抑制XLPE中羰基的形成和热氧老化,还可以在不降低交联度的前提下,改善XLPE抗焦烧性,避免预交联对XLPE性能的影响,且该材料具有更优的击穿强度温度特性和更低的介电损耗。 展开更多
关键词 交联聚乙烯 绝缘材料 交联剂 抗氧剂 击穿强度 热氧老化
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Development of a CLDN18.2-targeting immuno-PET probe for non-invasive imaging in gastrointestinal tumors 被引量:2
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作者 Yan Chen Xingguo Hou +11 位作者 Dapeng Li Jin Ding Jiayue Liu Zilei Wang Fei Teng Hongjun Li fan zhang Yi Gu Steven Yu Xueming Qian Zhi Yang Hua Zhu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第4期367-375,共9页
Claudin18.2(CLDN18.2)is a tight junction protein that is overexpressed in a variety of solid tumors such as gastrointestinal cancer and oesophageal cancer.It has been identified as a promising target and a potential b... Claudin18.2(CLDN18.2)is a tight junction protein that is overexpressed in a variety of solid tumors such as gastrointestinal cancer and oesophageal cancer.It has been identified as a promising target and a potential biomarker to diagnose tumor,evaluate efficacy,and determine patient prognosis.TST001 is a recombinant humanized CLDN18.2 antibody that selectively binds to the extracellular loop of human Claudin18.2.In this study,we constructed a solid target radionuclide zirconium-^(89)(^(89)Zr)labled-TST001 to detect the expression of in the human stomach cancer BGC823CLDN18.2 cell lines.The[^(89)Zr]Zr-desferrioxamine(DFO)-TST001 showed high radiochemical purity(RCP,>99%)and specific activity(24.15±1.34 GBq/mmol),and was stable in 5%human serum albumin,and phosphate buffer saline(>85%RCP at 96 h).The EC_(50) values of TST001 and DFO-TST001 were as high as 0.413±0.055 and 0.361±0.058 nM(P>0.05),respectively.The radiotracer had a significantly higher average standard uptake values in CLDN18.2-positive tumors than in CLDN18.2-negative tumors(1.11±0.02 vs.0.49±0.03,P=0.0016)2 days post injection(p.i.).BGC823CLDN18.2 mice models showed high tumor/muscle ratios 96 h p.i.with[^(89)Zr]Zr-DFO-TST001 was much higher than those of the other imaging groups.Immunohistochemistry results showed that BGC823CLDN18.2 tumors were highly positive(+++)for CLDN18.2,while those in the BGC823 group did not express CLDN18.2().The results of ex vivo biodistribution studies showed that there was a higher distribution in the BGC823CLDN18.2 tumor bearing mice(2.05±0.16%ID/g)than BGC823 mice(0.69±0.02%ID/g)and blocking group(0.72±0.02%ID/g).A dosimetry estimation study showed that the effective dose of[^(89)Zr]Zr-DFO-TST001 was 0.0705 mSv/MBq,which is within the range of acceptable doses for nuclear medicine research.Taken together,these results suggest that Good Manufacturing Practices produced by this immuno-positron emission tomography probe can detect CLDN18.2-overexpressing tumors. 展开更多
关键词 Claudin18.2 Gastrointestinal cancers Zirconium-89 Positron emission tomography Good Manufacturing Practices
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Improvement of inflammatory response and gastrointestinal function in perioperative of cholelithiasis by Modified Xiao-Cheng-Qi decoction 被引量:2
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作者 Bao-fang Sun fan zhang +4 位作者 Qiang-Pu Chen Qiang Wei Wen-Tao Zhu Hai-Bin Ji Xing-Yuan zhang 《World Journal of Clinical Cases》 SCIE 2023年第4期830-843,共14页
BACKGROUND In the perioperative period of biliary surgery,various factors can induce the release of a large number of inflammatory factors,leading to an imbalance in proinflammatory and anti-inflammatory responses and... BACKGROUND In the perioperative period of biliary surgery,various factors can induce the release of a large number of inflammatory factors,leading to an imbalance in proinflammatory and anti-inflammatory responses and resulting in gastrointestinal(GI)dysfunction.Enhanced Recovery After Surgery protocols in biliary surgery have been shown to reduce the stress response and accelerate postoperative recovery.It is crucial to reduce the inflammatory response and promote the recovery of GI function after biliary surgery,both of which are the basis and key for perioperative care and postoperative recovery.AIM To better understand the effects of Modified Xiao-Cheng-Qi decoction(MXD)on inflammatory response and GI function in the perioperative management of cholelithiasis and their correlation.METHODS This was a prospective randomized placebo-controlled trial,in which 162 patients who received biliary tract surgery were randomly assigned to three groups:MXD group,XD group,and placebo-control group.The observed parameters included frequency of bowel sounds,time of first flatus and defecation,time of diet,and amount of activity after surgery.The serum levels of C-reactive protein(CRP),interleukin(IL)-6,IL-10,serum amyloid A protein(SAA),and substance P were measured by the enzyme-linked immunosorbent assay.Then,the spearman correlation coefficient was used to analyze the relationship between the indicators of GI function and inflammation.RESULTS Compared to the placebo-control,improvements in GI function were observed in the MXD groups including reduced incidence of nausea,vomiting,and bloating;and earlier first exhaust time,first defecation time,and feeding time after surgery(P<0.05).On the 1st and 2nd d after surgery,IL-6,CRP and SAA levels in MXD group were lower than that in placebo control,but substance P level was higher,compared to the control(P<0.05).Functional diarrhea occurred in both MXD and XD groups without any other adverse effects,toxic reactions,and allergic reactions.Diarrhea was relieved after the discontinuation of the investigational remedies.Bowel sounds at 12 h after surgery,the occurring time of the first flatus,first defecation,postoperative liquid diet and semiliquid diet were significantly correlated with levels of IL-6,CRP,SAA and substance P on second day after surgery(P<0.05).CONCLUSION Treatment with MXD can relieve inflammatory response and improve GI function after surgery.Moreover,there are significant correlations between them.Furthermore,it does not cause serious adverse reactions. 展开更多
关键词 Modified Xiao-cheng-qi Decoction CHOLELITHIASIS Inflammatory response Gastrointestinal function Enhanced Recovery After Surgery PERIOPERATIVE
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A Review of Research on the Record-Breaking Precipitation Event in Henan Province,China,July 2021 被引量:1
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作者 Qinghong zhang Rumeng LI +3 位作者 Juanzhen SUN Feng LU Jun XU fan zhang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第8期1485-1500,共16页
A record-breaking precipitation event,with a maximum 24-h(1-h)precipitation of 624 mm(201.9 mm)observed at Zhengzhou Weather Station,occurred in Henan Province,China,in July 2021.However,all global operational forecas... A record-breaking precipitation event,with a maximum 24-h(1-h)precipitation of 624 mm(201.9 mm)observed at Zhengzhou Weather Station,occurred in Henan Province,China,in July 2021.However,all global operational forecast models failed to predict the intensity and location of maximum precipitation for this event.The unexpected heavy rainfall caused 398 deaths and 120.06 billion RMB of economic losses.The high-societal-impact of this event has drawn much attention from the research community.This article provides a research review of the event from the perspectives of observations,analysis,dynamics,predictability,and the connection with climate warming and urbanization.Global reanalysis data show that there was an anomalous large-scale circulation pattern that resulted in abundant moisture supply to the region of interest.Three mesoscale systems(a mesoscale low pressure system,a barrier jet,and downslope gravity current)were found by recent high-resolution model simulation and data assimilation studies to have contributed to the local intensification of the rainstorm.Furthermore,observational analysis has suggested that an abrupt increase in graupel through microphysical processes after the sequential merging of three convective cells contributed to the record-breaking precipitation.Although these findings have aided in our understanding of the extreme rainfall event,preliminary analysis indicated that the practical predictability of the extreme rainfall for this event was rather low.The contrary influences of climate warming and urbanization on precipitation extremes as revealed by two studies could add further challenges to the predictability.We conclude that data sharing and collaboration between meteorological and hydrological researchers will be crucial in future research on high-impact weather events. 展开更多
关键词 extreme precipitation observation dynamics PREDICTABILITY climate warming URBANIZATION
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Anti-Disturbance Control for Tethered Aircraft System With Deferred Output Constraints 被引量:1
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作者 Mengshi Song fan zhang +1 位作者 Bingxiao Huang Panfeng Huang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第2期474-485,共12页
In this paper,we investigate the peaking issue of extended state observers and the anti-disturbance control problem of tethered aircraft systems subject to the unstable flight of the main aircraft,airflow disturbances... In this paper,we investigate the peaking issue of extended state observers and the anti-disturbance control problem of tethered aircraft systems subject to the unstable flight of the main aircraft,airflow disturbances and deferred output constraints.Independent of exact initial values,a modified extended state observer is constructed from a shifting function such that not only the peaking issue inherently in the observer is circumvented completely but also the accurate estimation of the lumped disturbance is guaranteed.Meanwhile,to deal with deferred output constraints,an improved output constrained controller is employed by integrating the shifting function into the barrier Lyapunov function.Then,by combining the modified observer and the improved controller,an anti-disturbance control scheme is presented,which ensures that the outputs with any bounded initial conditions satisfy the constraints after a pre-specified finite time,and the tethered aircraft tracks the desired trajectory accurately.Finally,both a theoretical proof and simulation results verify the effectiveness of the proposed control scheme. 展开更多
关键词 Anti-disturbance control deferred output constraint extended state observer shifting function tethered aircraft system(TAS)
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基于沉后水浑浊度优化目标的中小型水厂侧向流斜板沉淀池改造 被引量:1
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作者 董志锋 刘倩 +2 位作者 范漳 林佳玲 曾威龙 《净水技术》 CAS 2023年第6期199-204,共6页
针对深圳某水厂斜管沉淀池沉淀效果差、排泥不畅、沉后水浑浊度偏高,最终导致滤池过滤周期短、滤后水及出厂水浑浊度偏高等问题,将斜管沉淀池改造为A型侧向流斜板沉淀池。改造并优化完成后,沉淀池空间利用率更高,运行更加平稳,对原水水... 针对深圳某水厂斜管沉淀池沉淀效果差、排泥不畅、沉后水浑浊度偏高,最终导致滤池过滤周期短、滤后水及出厂水浑浊度偏高等问题,将斜管沉淀池改造为A型侧向流斜板沉淀池。改造并优化完成后,沉淀池空间利用率更高,运行更加平稳,对原水水质波动的抗冲击能力也有一定提升。对比相同工艺改造前后的水质效果,发现经过改造优化后,因进水导流区及运行死角的消除,沉淀池运行有效容积由74.1%提升至100.0%,沉后水平均浑浊度下降26%,平均值在0.51 NTU,滤后水平均浑浊度下降19%,平均值为0.13 NTU。运行结果表明,A型侧向流斜板沉淀池改造效果显著,适用于存在相似问题的中小型水厂。 展开更多
关键词 侧向流斜板沉淀池 有效容积 出水浑浊度 斜板除泥装置 浑浊度
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Melatonin inhibits ESCC tumor growth by mitigating the HDAC7/β-catenin/c-Myc positive feedback loop and suppressing the USP10-maintained HDAC7 protein stability
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作者 Zhi-Qiang Ma Ying-Tong Feng +13 位作者 Kai Guo Dong Liu Chang-Jian Shao Ming-Hong Pan Yi-Meng zhang Yu-Xi zhang Di Lu Di Huang fan zhang Jin-Liang Wang Bo Yang Jing Han Xiao-Long Yan Yi Hu 《Military Medical Research》 SCIE CAS CSCD 2023年第2期207-226,共20页
Background:Melatonin,a natural hormone secreted by the pineal gland,has been reported to exhibit antitumor properties through diverse mechanisms of action.However,the oncostatic function of melatonin on esophageal squ... Background:Melatonin,a natural hormone secreted by the pineal gland,has been reported to exhibit antitumor properties through diverse mechanisms of action.However,the oncostatic function of melatonin on esophageal squamous cell carcinoma(ESCC) remains elusive.This study was conducted to investigate the potential effect and underlying molecular mechanism of melatonin as single anticancer agent against ESCC cells.Methods:ESCC cell lines treated with or without melatonin were used in this study.In vitro colony formation and 5-Ethynyl-2’-deoxyuridine(EdU) incorporation assays,and nude mice tumor xenograft model were used to confirm the proliferative capacities of ESCC cells.RNA-seq,qPCR,Western blotting,recombinant lentivirus-mediated target gene overexpression or knockdown,plasmids transfection and co-IP were applied to investigate the underlying molecular mechanism by which melatonin inhibited ESCC cell growth.IHC staining on ESCC tissue microarray and further survival analyses were performed to explore the relationship between target genes’ expression and prognosis of ESCC.Results:Melatonin treatment dose-dependently inhibited the proliferative ability and the expression of histone deacetylase 7(HDAC7),c-Myc and ubiquitin-specific peptidase 10(USP10) in ESCC cells(P<0.05).The expressions of HDAC7,c-Myc and USP10 in tumors were significantly higher than the paired normal tissues from 148 ESCC patients(P<0.001).Then,the Kaplan-Meier survival analysis suggested that ESCC patients with high HDAC7,c-Myc or USP10levels predicted worse overall survival(log-rank P<0.001).Co-IP and Western blotting further revealed that HDAC7physically deacetylated and activated β-catenin thus promoting downstream target c-Myc gene transcription.Notably,our mechanistic study validated that HDAC7/β-catenin/c-Myc could form the positive feedback loop to enhance ESCC cell growth,and USP10 could deubiquitinate and stabilize HDAC7 protein in the ESCC cells.Additionally,we verified that inhibition of the HDAC7/β-catenin/c-Myc axis and USP10/HDAC7 pathway mediated the anti-proliferative action of melatonin on ESCC cells.Conclusions:Our findings elucidate that melatonin mitigates the HDAC7/β-catenin/c-Myc positive feedback loop and inhibits the USP10-maintained HDAC7 protein stability thus suppressing ESCC cell growth,and provides the reference for identifying biomarkers and therapeutic targets for ESCC. 展开更多
关键词 MELATONIN Histone deacetylase 7(HDAC7) Β-CATENIN C-MYC Ubiquitin-specifc peptidase 10(USP10) Esophageal squamous cell carcinoma(ESCC)
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Influence of Cavitation on Unsteady Vortical Flows in a Side Channel Pump
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作者 Yefang Wang fan zhang +3 位作者 Shouqi Yuan Ke Chen Feng Hong Desmond Appiah 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第1期171-189,共19页
Previous investigation on side channel pump mainly concentrates on parameter optimization and internal unsteady vortical flows.However,cavitation is prone to occur in a side channel pump,which is a challenging issue i... Previous investigation on side channel pump mainly concentrates on parameter optimization and internal unsteady vortical flows.However,cavitation is prone to occur in a side channel pump,which is a challenging issue in promoting performance.In the present study,the cavitating flow is investigated numerically by the turbulence model of SAS combined with the Zwart cavitation model.The vapors inside the side channel pump firstly occur in the impeller passage near the inlet and then spread gradually to the downstream passages with the decrease of NPSHa.Moreover,a strong adverse pressure gradient is presented at the end of the cavity closure region,which leads to cavity shedding from the wall.The small scaled vortices in each passage reduce significantly and gather into larger vortices due to the cavitation.Comparing the three terms of vorticity transport equation with the vapor volume fraction and vorticity distributions,it is found that the stretching term is dominant and responsible for the vorticity production and evolution in cavitating flows.In addition,the magnitudes of the stretching term decrease once the cavitation occurs,while the values of dilatation are high in the cavity region and increase with the decreasing NPSHa.Even though the magnitude of the baroclinic torque term is smaller than vortex stretching and dilatation terms,it is important for the vorticity production along the cavity surface and near the cavity closure region.The pressure fluctuations in the impeller and side channel tend to be stronger due to the cavitation.The primary frequency of monitor points in the impeller is 24.94 Hz and in the side channel is 598.05 Hz.They are quite corresponding to the shaft frequency of 25 Hz(fshaft=1/n=25 Hz)and the blade frequency of 600 Hz(fblade=Z/n=600 Hz)respectively.This study complements the investigation on cavitation in the side channel pump,which could provide the theoretical foundation for further optimization of performance. 展开更多
关键词 Side channel pump Vortical flows CAVITATION Vortex-cavitation interaction Pressure fluctuation
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A novel candidate gene CLN8 regulates fat deposition in avian
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作者 Xiaoqin Li fan zhang +4 位作者 Yunxiao Sun Dandan Sun fangxi Yang Yongtong Liu Zhuocheng Hou 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第5期1895-1908,共14页
Background The fat deposition has a crucial role in animal meat flavor,and fat deposition-related traits are vital for breeding in the commercial duck industry.Avian fat-related traits are typical complex phenotypes,w... Background The fat deposition has a crucial role in animal meat flavor,and fat deposition-related traits are vital for breeding in the commercial duck industry.Avian fat-related traits are typical complex phenotypes,which need a large amount of data to analyze the genetic loci.Results In this study,we performed a new phenotypic analysis of fat traits and genotyped whole-genome varia-tions for 1,246 ducks,and combed with previous GWAS data to reach 1,880 ducks for following analysis.The carcass composition traits,subcutaneous fat weight(SFW),subcutaneous fat percentage(SFP),abdominal fat weight(AFW),abdominal fat percentage(AFP)and the body weight of day 42(BW42)for each duck were collected.We identified a set of new loci that affect the traits related to fat deposition in avian.Among these loci,ceroid-lipofuscinosis,neuronal 8(CLN8)is a novel candidate gene controlling fat deposition.We investigated its novel function and regulation in avian adipogenesis.Five significant SNPs(the most significant SNP,P-value=21.37E-12)and a single haplotype were detected in the upstream of CLN8 for subcutaneous fat percentage.Subsequently,luciferase assay demonstrated that 5 linked SNPs in the upstream of the CLN8 gene significantly decreased the transcriptional activity of CLN8.Further,ATAC-seq analysis showed that transcription factor binding sites were identified in a region close to the haplotype.A set of luciferase reporter gene vectors that contained different deletion fragments of the CLN8 promoter were con-structed,and the core promoter area of CLN8 was finally identified in the-1,884/-1,207 bp region of the 5′flanking sequences,which contains adipogenesis-related transcription factors binding sites.Moreover,the over-expression of CLN8 can remarkably facilitate adipocyte differentiation in ICPs.Consistent with these,the global transcriptome profiling and functional analysis of the over-expressed CLN8 in the cell line further revealed that the lipid biosynthetic process during the adipogenesis was significantly enriched.Conclusions Our results demonstrated that CLN8 is a positive regulator of avian adipocyte differentiation.These findings identify a novel function of CLN8 in adipocyte differentiation,which provides important clues for the further study of the mechanism of avian fat deposition. 展开更多
关键词 AVIAN ADIPOGENESIS CLN8 SNP Transcription regulation
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