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PU基体和吸波材料热带海洋大气环境下力学性能变化规律研究
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作者 罗丹 吴欣睿 +5 位作者 任宏宇 李昊瑜 李旭 彭冬 李晗 李鸿飞 《环境技术》 2026年第1期18-22,共5页
为研究PU基体和吸波材料在热带海洋大气环境下的力学性能变化规律。在某试验站采用黑箱暴露贮存方式开展1年的暴露贮存试验,分别通过拉伸强度与断裂伸长率研究其力学性能变化规律。PU基体和吸波材料在1年的黑箱暴露贮存试验下,其力学性... 为研究PU基体和吸波材料在热带海洋大气环境下的力学性能变化规律。在某试验站采用黑箱暴露贮存方式开展1年的暴露贮存试验,分别通过拉伸强度与断裂伸长率研究其力学性能变化规律。PU基体和吸波材料在1年的黑箱暴露贮存试验下,其力学性能呈总体下降趋势,并在贮存1年左右就发生了明显的粉化现象。而吸波材料的防水覆膜对材料具有明显的保护作用,大大降低了对空气中水汽的敏感性。吸波材料在热带海洋大气环境下的力学性能优于PU基体。 展开更多
关键词 pu基体 吸波材料 热带海洋大气环境 力学性能变化规律
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基于变轴线运动副3(rU)PU变胞并联机构设计
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作者 冯盛权 屈淑维 +2 位作者 李瑞琴 姚威 马春生 《中国机械工程》 北大核心 2026年第2期361-373,共13页
运用螺旋理论的线几何法分析UPU支链中运动副轴线之间的几何关系,发现几何关系不同,则支链的约束不同,根据这一规律设计了一种由U副、滑块和滑轨组成的变轴线运动副(rU)。通过滑块在滑轨上滑动来带动与滑块连接的U副滑动,实现U副中一个... 运用螺旋理论的线几何法分析UPU支链中运动副轴线之间的几何关系,发现几何关系不同,则支链的约束不同,根据这一规律设计了一种由U副、滑块和滑轨组成的变轴线运动副(rU)。通过滑块在滑轨上滑动来带动与滑块连接的U副滑动,实现U副中一个转动副轴线方向的变化,从而改变轴线之间的几何关系。用变轴线运动副(rU)代替UPU支链上的U副,使得3(rU)PU变胞并联机构可以实现三转动(3R)和三移动(3T)两种运动。提出UPU支链的等效平面,并将该等效平面应用于运动中3(rU)PU变胞机构自由度的分析。基于等边三角形的相似性设计了一种可伸缩平台,用于调整下平台的大小。通过仿真实验证明该变胞机构可实现3R-3T两种运动模式,该机构被应用于位姿调整中。 展开更多
关键词 3(rU)pu变胞并联机构 变轴线运动副 3R-3T运动模式 切换方案 位姿调整
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三氧化铀中Pu和Np的α放射性比活度分析
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作者 孙媛媛 张相鲁 +2 位作者 李春艳 牟凌 杨利 《核化学与放射化学》 北大核心 2026年第1期52-57,I0003,共7页
三氧化铀中Pu和Np的α放射性比活度是产品质量质控的重要参数。本研究基于TEVA树脂建立高铀样品中Pu和Np放射性比活度α谱仪准确测量的方法。该方法首先将铀氧化物粉末溶解到2 mL的5 mol/L HNO_(3)中,加入0.1 mL 30%(质量分数)H_(2)O_(2... 三氧化铀中Pu和Np的α放射性比活度是产品质量质控的重要参数。本研究基于TEVA树脂建立高铀样品中Pu和Np放射性比活度α谱仪准确测量的方法。该方法首先将铀氧化物粉末溶解到2 mL的5 mol/L HNO_(3)中,加入0.1 mL 30%(质量分数)H_(2)O_(2)将Pu和Np调节为+4价;随后用TEVA树脂吸附Pu和Np,并用10 mL5 mol/L HNO_(3)+0.1 mL 30%H_(2)O_(2)溶液洗涤树脂去除干扰元素U,最后用10 mL 0.3 mol/L HNO_(3)+0.02 mol/L H_(2)C_(2)O_(4)溶液洗脱Pu和Np。实验表明:99%以上的U穿透树脂而被去除,U的去污因子>3.2×10^(4),Pu和Np的回收率>90%,适用于0.1~0.5 g三氧化铀中Pu和Np的放射性比活度测量。加标实验结果表明期望值与测量值吻合,相对偏差在-2%~5%之间。空白流程的分析结果证明,当三氧化铀样品取样量为0.2 g时,本方法对Pu和Np的检出限为2.7 Bq/g,满足后处理工艺对铀氧化物粉末中Pu和Np放射性比活度的分析要求。 展开更多
关键词 三氧化铀 TEVA树脂 pu NP
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Pyridine-based ionic sp^(2)carbon-conjugated covalent organic frameworks for selective extraction of Pu(Ⅳ)from high-level liquid waste
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作者 Li-Ying Wang Jun-jie Yu +6 位作者 Shuai Wang Yang Liu Ke-Xian Song Ji-Pan Yu Li-Yong Yuan Zhi-Rong Liu Wei-Qun Shi 《Chinese Chemical Letters》 2025年第8期337-343,共7页
In the current era marked by energy shortages,the advancement of nuclear energy stands as an inevitable progression.The reprocessing of spent nuclear fuel plays a crucial role in determining the sustainability of nucl... In the current era marked by energy shortages,the advancement of nuclear energy stands as an inevitable progression.The reprocessing of spent nuclear fuel plays a crucial role in determining the sustainability of nuclear energy as a viable energy source.Among these processes,the separation and recovery of Pu(Ⅳ)from high-level liquid waste(HLLW)hold paramount significance in terms of safety and strategic implications.Herein,this work focused on the synthesis of two acid-and radiation-resistant pyridine-based sp^(2)c-COFs(COF-IHEP3 and COF-IHEP4),followed by the creation of two pyridine-based ionized sp^(2)c-COFs named COF-IHEP3-CH_(3)NO_(3)and COF-IHEP4-CH3NO3through post-modification.These materials have potential anion exchange capacity for the selective separation of Pu(Ⅳ)in highly acidic conditions.Notably,in 8 mol/L nitric acid solution,COF-IHEP3-CH3NO3demonstrated the capability to eliminate plutonium within 20 min in 98%removal efficiency with a Kdvalue of 2450 m L/g.Experimental and theoretical analysis suggest that the ionized sp^(2)c-COFs exhibit exceptional stability,selectivity,and prevention of secondary contamination towards Pu(Ⅳ)in the presence of multiple ions environments.In short,this work provides an appropriate anion exchange strategy to design ionic sp^(2)c-COFs as a promising platform for Pu(Ⅳ)recovery from HLLW. 展开更多
关键词 Covalentorganic framework Highlyacidic conditions High-level liquidwaste anion exchange pu(IV)
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Acupuncture treatment for Bartholin’s abscesst:A case report and literature review
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作者 Xiao-xuan GENG Sheng CHEN +2 位作者 Wen-yi YANG Mei-lun HUANG Jia-le KANG 《World Journal of Acupuncture-Moxibustion》 2025年第4期384-387,共4页
A 30-year-old female patient with Bartholin’s abscess was treated by acupuncture.Before visit,she had taken wuwei xiaodu yin for 4 consecutive days,but the symptoms were not alleviated markedly and pain was worsening... A 30-year-old female patient with Bartholin’s abscess was treated by acupuncture.Before visit,she had taken wuwei xiaodu yin for 4 consecutive days,but the symptoms were not alleviated markedly and pain was worsening.According to the conditions of tongue and pulse,and physical signs,the case was differ-entiated as pathogenic heat invading blood phase;and the injury of qi and yin by the herbal decoction the patient took before.In treatment with acupuncture,the treatment principle focused on benefiting qi,nourishing yin,expelling pus from the interior and draining toxin,and promoting the circulations of meridians to stop pain.He-sea points were selected to clear heat and resolve damp,and replenish the liver and kidney;and the acupoints of bladder meridian were combined under the guidance of“taiyang dominating the openings,”aiming at elevating qi and expelling toxin from the interior.Acupuncture was given once daily.After treated for 4 days,abscess was ruptured,pain disappeared,and no recurrence was presented and no sequelae happened during over 2 years of follow-up.This case shows that acupuncture is effective on Bartholin’s abscess.By reviewing this case,it is put forward that there may by the signs before the onset of Bartholin’s abscess,and the treatment should focus on opening a way for eliminating pathogens.Moreover,the clinical trial is required to verify acupuncture effect on this disease. 展开更多
关键词 Bartholin’s abscess CARBUNCLE Acupuncture Blood phase Expelling pus from interior and drawing toxin
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PU.1 regulation of type 1 dendritic cell function via NF-κB pathway in inhibition of non-small cell lung cancer progression
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作者 Tingting Wang Yishuo Li +3 位作者 Qiongyu Duan Chunlei Wang Yixian Wang Tianyu Hu 《Journal of Pharmaceutical Analysis》 2025年第7期1565-1584,共20页
This research investigates the regulatory role of the transcription factor PU.1 in type 1 conventional dendritic cells(cDC1)and its therapeutic potential of modulating the nuclear factor kappaB(NF-κB)cells signaling ... This research investigates the regulatory role of the transcription factor PU.1 in type 1 conventional dendritic cells(cDC1)and its therapeutic potential of modulating the nuclear factor kappaB(NF-κB)cells signaling pathway in non-small cell lung cancer(NSCLC).Utilizing single-cell transcriptome sequencing and comprehensive bioinformatics tools,including the CIBERSORT algorithm,we analyzed the immune cell landscape within NSCLC tissues.Our analysis revealed distinct NSCLC subtypes and delineated the developmental trajectories and functional distinctions of cDC1 cells.Key differentially expressed genes(DEGs)and pivotal functional modules within these cells were identified,highlighting PU.1 as a critical mediator underexpressed in NSCLC samples.Functionally,PU.1 demonstrated the induction of the NF-κB pathway,which led to inhibited tumor proliferation and enhanced activation of cDC1,thereby suggesting its role in tumor immune surveillance.In vivo models confirmed the suppressive effect of PU.1 on NSCLC progression,mediated through its influence on cDC1 functionality via the NF-κB pathway.These findings propose PU.1 as a promising target for NSCLC therapeutic strategies,emphasizing the importance of transcriptional regulators in the tumor microenvironment. 展开更多
关键词 Non-small cell lung cancer pu.1 NF-κB signaling pathway cDC1 Single-cell transcriptome sequencing Immune infiltration
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Chemistry and potential applications of multifunctional polymer nanocomposite coatings:A review
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作者 A.M.FADL 《Journal of Central South University》 2026年第1期1-49,共49页
Polymer nanocomposite coatings(PNCCs)are unprecedented generation of coatings engineered for displaying inexpensive and brilliant functional surface coatings with eminent corrosion guard,mechanical resistance,antimicr... Polymer nanocomposite coatings(PNCCs)are unprecedented generation of coatings engineered for displaying inexpensive and brilliant functional surface coatings with eminent corrosion guard,mechanical resistance,antimicrobial,chemical durability,electrical insulation,and UV aging features.Due to their widely anticipation in petroleum,applications in building,conveyance,aerospace,electronics,automobiles and energy,these multi-functional coatings have a tremendous leverage in human life,all technological and scientific subjects.Numerous applications have been made for multilateral polymers like polyurethane(PU),epoxy(EP),polyaniline(PANI)conductive polymer,polypyrrole(PPy),and etc,on various metallic surfaces especially,carbon steel substrate owing to their excellent resistance properties.Practically,nanomaterials can possess potential in the all-interdisciplinary domains of materials science and engineering,chemical and physical sciences,biological and health sciences.As known,the designed polymer nanocomposite coating paradigm is fundamentally constituted from polymer or resin as a vehicle and inorganic nanofillers(nanoparticles and nanocomposites).Some commercialized and excessively employed nanocontainers in polymer nanocomposite coating formulations,like ZnO,TiO_(2),carbon nanotubes(CNTs),clay,SiO_(2),Al_(2)O_(3),graphene,GO,CeO_(2),ZrO_(2),FeTiO_(3),etc were discussed.The current review covered the chemistry and potential applications of the largest utilized multifunctional polymer nanocomposite coatings such as EP,PU and other considerable PNCCs.Lately,a titanic attention was made for epoxy nanocomposites because of their distinct physicochemical characteristics,which result from the combined qualities of the nanoparticles and polymer material unity.In addition,the author incorporated some of his scientific contributions in this area represented in construction of innovative functional polymer nanocomposites for a variety of uses with high economic,industrial impacts and future orientation.Furthermore,some newly published applications of polymer nanocomposite coatings were incorporated and discussed. 展开更多
关键词 polymer nanocomposite coatings(PNCCs) multifunctional properties corrosion mitigation mechanical resistance chemical durability anTIMICROBIAL UV aging epoxy(EP) polyurethane(pu) NanOCONTAINERS economic and industrial potentials
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静电纺PU/PANI纳米纤维膜制备及性能研究 被引量:4
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作者 范兰兰 贾志霞 +3 位作者 鞠敬鸽 马晓敏 赵卉卉 康卫民 《化工新型材料》 CAS CSCD 北大核心 2017年第2期61-63,66,共4页
以聚苯胺(PANI)和聚氨酯(PU)等为原料,采用静电纺丝技术,成功制备PU/PANI纳米纤维膜。采用SEM扫描电镜研究了PU/PANI配比、纺丝液浓度、挤出速度等对纤维形貌与结构的影响,并研究了其力学性能、过滤性能以及电学性能。结果表明,当PU/PAN... 以聚苯胺(PANI)和聚氨酯(PU)等为原料,采用静电纺丝技术,成功制备PU/PANI纳米纤维膜。采用SEM扫描电镜研究了PU/PANI配比、纺丝液浓度、挤出速度等对纤维形貌与结构的影响,并研究了其力学性能、过滤性能以及电学性能。结果表明,当PU/PANI质量配比为10∶1,纺丝液质量浓度为8%,挤出速度为6mL/h时,纺丝效果最佳,制得纳米纤维直径分布较为均匀,约为300~500nm。添加一定量的PANI可提高纺丝液电导率,有助于改善静电纺丝效果,降低纳米纤维直径;PU/PANI纳米纤维膜阻抗比纯聚氨酯纳米纤维小2个数量级,具有优良的抗静电性。在32L/min流量下,对0.3μm的粒子,过滤效率达96.0%以上,是一种优异高效抗静电过滤材料。在易燃易爆、安全过滤、特种工况防护服装中具有潜在的应用前景。 展开更多
关键词 静电纺丝 pu/PanI 纳米纤维膜 过滤材料
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nano-SiO_2/PU亲水性注浆材料的制备与性能研究
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作者 李雅迪 范仁祥 +3 位作者 朱锦 孙晓红 Ali Bahader 丁运生 《中国建筑防水》 2015年第13期6-10,共5页
分别采用预聚体法和原位聚合法制备了nano-SiO2/PU复合注浆液,研究了nano-SiO2的含量与制备方法对复合注浆液及其固结体性能的影响。结果表明,与PU注浆液相比,nano-SiO2/PU复合注浆液热稳定性得到了提高,固结体的压缩强度也明显增加。
关键词 nano-SiO2/pu复合注浆液 固结体 原位聚合法 压缩强度
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加速器质谱测量海水中^(239)Pu
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作者 邬蒙蒙 尹云云 +3 位作者 郭庐阵 吕天林 汪传高 庞洪超 《辐射防护》 北大核心 2025年第2期133-140,共8页
采用中国原子能科学研究院自主研制的加速器质谱(AMS)系统对海水中^(239)Pu进行测量,用阴离子树脂对样品中^(239)Pu进行了分离纯化、氢氧化铁共沉淀法制备测量使用靶样品。制备一组自来水样品作为空白样品得到测量方法的检出限为0.9 fg(... 采用中国原子能科学研究院自主研制的加速器质谱(AMS)系统对海水中^(239)Pu进行测量,用阴离子树脂对样品中^(239)Pu进行了分离纯化、氢氧化铁共沉淀法制备测量使用靶样品。制备一组自来水样品作为空白样品得到测量方法的检出限为0.9 fg(2.0μBq),对实际海水样品中^(239)Pu进行了测量和分析,并对测量方法的不确定度进行了分析。 展开更多
关键词 加速器质谱 海水 放射性测量 ^(239)pu
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Pu和Tc在北山新场花岗岩及其裂隙填充物中的扩散行为
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作者 周舵 王波 +3 位作者 陈曦 商澄铭 陈平 周明芳 《核化学与放射化学》 北大核心 2025年第6期635-642,I0002,共9页
为评估我国高放废物深地质处置库预选区场址的长期安全性,针对我国北山预选区新场花岗岩及其裂隙填充物,系统开展了关键放射性核素^(238)Pu和^(99)Tc的扩散行为实验。通过恒定源贯穿扩散法测定了低氧条件下核素在北山新场花岗岩完整样... 为评估我国高放废物深地质处置库预选区场址的长期安全性,针对我国北山预选区新场花岗岩及其裂隙填充物,系统开展了关键放射性核素^(238)Pu和^(99)Tc的扩散行为实验。通过恒定源贯穿扩散法测定了低氧条件下核素在北山新场花岗岩完整样片及北山新场花岗岩裂隙填充物中的有效扩散系数(De),结果显示:对于北山新场花岗岩完整样片和北山新场花岗岩裂隙填充物,有效扩散系数的大小顺序均为:De(HTO)>De(Tc)>De(Pu);由于北山新场花岗岩完整样片的致密度远大于其裂隙填充物的致密度,导致HTO、^(238)Pu和^(99)Tc在北山新场花岗岩完整样片中的有效扩散系数远小于其在裂隙填充物中的有效扩散系数。本研究证实,相对HTO而言,北山新场花岗岩及其裂隙物均对^(238)Pu和^(99)Tc的迁移具有一定程度上的阻滞效果,但对Pu效果更显著,可能是Pu与这两种介质存在更复杂的吸附反应。值得注意的是,花岗岩完整岩片对某些核素可能不能简单当作均匀介质对待,其中可能存在优势通道,不利于核素的阻滞。 展开更多
关键词 ^(238)pu ^(99)Tc 北山新场花岗岩 裂隙填充物 扩散
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基于PU学习的科技领域文献集自动降噪方法研究
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作者 陈果 杨泽雨 +1 位作者 陈晶 邵雨 《情报学报》 北大核心 2025年第4期414-424,共11页
在开展领域文献分析时,通过惯用方式构造的文献集普遍存在相当比例的非领域相关文献,降低了最终结果的可靠性,因此,有必要对其开展降噪以剔除杂质。如何实现在无人工标注的前提下开展文献集的自动降噪,是保障降噪方案的领域泛化性、实... 在开展领域文献分析时,通过惯用方式构造的文献集普遍存在相当比例的非领域相关文献,降低了最终结果的可靠性,因此,有必要对其开展降噪以剔除杂质。如何实现在无人工标注的前提下开展文献集的自动降噪,是保障降噪方案的领域泛化性、实践应用可行性的必要前提。本文在充分利用原始文献集自身特征的前提下,将领域文献集降噪任务转化为一个在自动构造正负样本集基础上的分类问题;其思路是利用文献集当中自然存在且易识别的一批绝对正样本集,开展PU(positive-unlabeled)分类学习,定位出一批可靠负样本集,以训练最终分类器。本文以人工智能、经济学和免疫学领域MAG(Microsoft Academic Graph)期刊文献集为例,开展了对比实验,比较了降噪方案中选择不同语义表示方法对最终降噪性能的影响,进一步构造了一个基准比较值,引入归一化折扣累积收益这一评价指标,从降噪收益、最终结果可用性以及文献降噪在科技领域情报分析多种任务场景下的有效性3个方面证明了本文方案的有效性。 展开更多
关键词 领域分析 领域文献集 文献计量 数据集降噪 pu学习
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撞击荷载作用下PU泡沫防护RC柱抗冲击数值模拟研究
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作者 何庆锋 张俊峰 +1 位作者 易帆 唐志龙 《振动与冲击》 北大核心 2025年第14期120-131,共12页
缓冲泡沫构型防护措施具有优良的防护效果,为探究所设计防护的钢筋混凝土(reinforced concrete,RC)柱在碰撞过程中的耗能效果及防撞机理,基于摆锤冲击试验数据,采用LS-DYNA软件对冲击作用下RC柱的动态响应与破坏模式进行数值模拟与模型... 缓冲泡沫构型防护措施具有优良的防护效果,为探究所设计防护的钢筋混凝土(reinforced concrete,RC)柱在碰撞过程中的耗能效果及防撞机理,基于摆锤冲击试验数据,采用LS-DYNA软件对冲击作用下RC柱的动态响应与破坏模式进行数值模拟与模型有效性验证。对比研究了无防护、采用聚氨酯(polyurethanes,PU)泡沫防护以及钢丝网砂浆综合防护等三种措施下的不同设计参数的RC柱抗冲击性能,结果表明,该研究所采取的两种防护措施均可显著提高RC柱抗冲击性能。在摆锤冲击荷载作用下,钢丝网砂浆-PU泡沫防护措施具有优异的抗冲击防护效果,相对于仅使用PU泡沫防护,在同样的防护厚度下,PU泡沫外层设置钢丝网复合砂浆相比来说可以分别降低冲击力峰值与位移峰值约20%、25%;在不同冲击速度下均有较好的耐撞性能,增加缓冲层的厚度与密度均能有效提升RC柱的抗冲击性能。 展开更多
关键词 摆锤冲击试验 聚氨酯(pu)泡沫 防护措施 抗冲击性能 能量耗散
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La, Ce, Pr, Nd and Sm concentrations in Pu’er tea of Yunnan, China 被引量:12
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作者 宁蓬勃 龚春梅 +1 位作者 张彦明 郭抗抗 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第4期636-640,共5页
The rare earth elements contents (La, Ce, Pr, Nd, Sm) in 150 Pu er tea samples were analyzed by using inductively coupled plasma atomic emission spectroscopy (ICP-AES), to evaluate the safety of Pu er tea. Among the i... The rare earth elements contents (La, Ce, Pr, Nd, Sm) in 150 Pu er tea samples were analyzed by using inductively coupled plasma atomic emission spectroscopy (ICP-AES), to evaluate the safety of Pu er tea. Among the investigated rare earth elements (REEs), Ce was the highest (35% of the total REEs content) whose concentrations were found to be in the range of 0.11–1.39 mg/kg, whereas that of Sm in the range 0.01–0.21 mg/kg, showing minimum levels (5.2%). La was the second highest element (28%) found in Pu e... 展开更多
关键词 LA CE PR ND SM pu er tea quality safety rare earths
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3D打印用PC/PCL/PU复合隐形牙套材料制备与性能研究
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作者 何显运 《粘接》 2025年第9期102-104,共3页
研究了3D打印用PC/PCL/PU复合隐形牙套材料的制备与性能。针对隐形牙套材料依赖进口和传统注塑工艺局限,提出三元复合改性策略开发高性能国产材料,分析组分比例对材料性能的协同影响。结果显示,在流动性和韧性方面具有优势,一定程度上... 研究了3D打印用PC/PCL/PU复合隐形牙套材料的制备与性能。针对隐形牙套材料依赖进口和传统注塑工艺局限,提出三元复合改性策略开发高性能国产材料,分析组分比例对材料性能的协同影响。结果显示,在流动性和韧性方面具有优势,一定程度上改善了PLA材料的综合性能。PCL能够提升流动性,但拉伸强度和弹性模量降低;PU增强冲击强度和韧性,复合材料相容性和可加工性良好。 展开更多
关键词 3D打印 隐形牙套 PC/PCL/pu复合材料
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Indeterminate pulmonary nodules in colorectal cancer 被引量:5
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作者 Eun-Joo Jung Su-Ran Kim +3 位作者 Chun-Geun Ryu Jin Hee Paik Jeong Geun Yi Dae-Yong Hwang 《World Journal of Gastroenterology》 SCIE CAS 2015年第10期2967-2972,共6页
AIM:To investigate the clinicopathologic parameters of pulmonary metastasis in colorectal cancer(CRC) patients after lung operation of indeterminate pulmonary nodules(IPNs).METHODS:From a prospective database of CRCpa... AIM:To investigate the clinicopathologic parameters of pulmonary metastasis in colorectal cancer(CRC) patients after lung operation of indeterminate pulmonary nodules(IPNs).METHODS:From a prospective database of CRCpatients,40 cases that underwent lung operation between November 2008 and December 2012 for suspicious metastatic pulmonary nodules on chest computed tomography(CT)were enrolled.The decision to perform a lung operation was made if the patient met the following criteria:(1)completely resected or resectable primary CRC;(2)completely resectable IPNs;(3)controlled or controllable extrapulmonary metastasis;and(4)adequate general condition and pulmonary function to tolerate pulmonary operation.Lung operation was performed by a thoracic surgeon without CT-guided biopsy for pathologic confirmation.RESULTS:A total of 40 cases of lung resection was performed in 29 patients.Five patients underwent repeated lung resection.The final pathology result showed metastasis from the CRC in 30 cases(75%)and benign pathology in 10 cases(25%).The primary tumor site was the rectum in 26/30(86.6%)cases with pulmonary metastasis,but only 3/10(30%)cases in the benign group had a primary rectal cancer(P=0.001).Positron emission tomography(PET)-CT was performed for 22/30(73.4%)patients in the lung metastasis group and for 6/10(60.0%)patients in the benign group.PET-CT revealed hot uptake of18fluorine 2-fluoro-2-deoxy-D-glucose with all IPNs in both groups.The group with pulmonary metastasis had a higher incidence of primary rectal cancer(P=0.001),a more advanced tumor stage(P=0.011),and more frequent lymphatic invasion of tumor cells(P=0.005).Six cases with previous liver metastasectomy were present in the lung metastasis group.Serum carcinoembryonic antigen levels before lung operation were not elevated in any of the patients.CONCLUSION:The stage and location of the primary tumor and tumor cell infiltration of lymphatics provide useful indicators for deciding on lung resection of IPNs in CRC. 展开更多
关键词 COLORECTAL NEOPLASM LUNG NEOPLASM INDETERMINATE pu
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Antibacterial Thermoplastic Polyurethane Electrospun Fiber Mats Prepared by 3-Aminopropyltriethoxysilane-assisted Adsorption of Ag Nanoparticles 被引量:4
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作者 Yu-man Liu 李强 +3 位作者 Huan-huan Liu Hui-hui Cheng Jian Yu 郭朝霞 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2017年第6期713-720,共8页
Antibacterial thermoplastic polyurethane (TPU) electrospun fiber mats were prepared by adsorption of Ag nanoparticles (Ag NPs) onto TPU/3-aminopropyltriethoxysilane (APS) co-electrospun fiber mats from silver so... Antibacterial thermoplastic polyurethane (TPU) electrospun fiber mats were prepared by adsorption of Ag nanoparticles (Ag NPs) onto TPU/3-aminopropyltriethoxysilane (APS) co-electrospun fiber mats from silver sol. The use of APS can functionalize TPU fibers with amino groups, facilitating the adsorption of Ag NPs. The effects of pH of silver sol and APS content on Ag NP adsorption and antibacterial activity were investigated. Ag NP adsorption was evidenced by TEM, XPS and TGA. Significant Ag NP adsorption occurred at pH = 3-5, The main driving force for Ag NP adsorption is electrostatic interaction between --NH3^+ of the fibers and --COO- derived from the --COOH group capped on the surfaces of Ag NPs. The antibacterial activity of the Ag NP-decorated TPU/APS fiber mats was investigated using both gram-negative Escherichia coli and gram-positive Bacillus subtilis. The antibacterial rate increases with increasing APS content up to 5% where the antibacterial rates against both types of bacteria are over 99.9%. 展开更多
关键词 pu ELECTROSPINNING Coupling agent IMMOBILIZATION Bacteria
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Downregulation of the Spi-1/PU.1 oncogene induces the expression of TRIM10/HERF1, a key factor required for terminal erythroid cell differentiation and survival 被引量:4
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作者 Rand Blaybel Orianne Theoleyre Alexandre Douablin Faouzi Baklouti 《Cell Research》 SCIE CAS CSCD 2008年第8期834-845,共12页
Sustained expression of the Spi-1/PU.1 and Fli-1 oncoproteins blocks globin gene activation in mouse erythroleukemia cells; however, only Spi-1/PU.1 expression inhibits the inclusion of exon 16 in the mature 4.1R mRNA... Sustained expression of the Spi-1/PU.1 and Fli-1 oncoproteins blocks globin gene activation in mouse erythroleukemia cells; however, only Spi-1/PU.1 expression inhibits the inclusion of exon 16 in the mature 4.1R mRNA. This splicing event is crucial for a functional 4.1R protein and, therefore, for red blood cell membrane integrity. This report demonstrates that Spi-1/PU.1 downregulation induces the activation of TRIM10/hematopoietic RING finger 1 (HERF1), a member of the tripartite motif (TRIM)/RBCC protein family needed for globin gene transcription. Additionally, we demonstrate that TRIM10/HERF1 is required for the regulated splicing of exon 16 during late erythroid differentia- tion. Using inducible overexpression and silencing approaches, we found that: (1) TRIM10/HERF1 knockdown inhibits hemoglobin production and exon splicing and triggers cell apoptosis in dimethylsulfoxide (DMSO)-induced cells; (2) TRIM10/HERF1 upregulation is required but is insufficient on its own to activate exon retention; (3) Fli-1 has no effect on TRIM10/HERFI expression, whereas either DMSO-induced downregulation or shRNA-knockdown of Spi-I/PU.I expression is sufficient to activate TRIM10/HERF1 expression; and (4) Spi-1/PU.1 knockdown triggers both the transcription and the splicing events independently of the chemical induction. Altogether, these data indicate that primary Spi-1/PU.1 downregulation acts on late erythroid differentiation through at least two pathways, one of which requires TRIM10/HERF1 upregulation and parallels the Spi-1/PU.1-induced Fli-1 shutoff regulatory cascade. 展开更多
关键词 alternative splicing erythroid differentiation HERF1 ONCOGENE protein 4.1R Spi-1/pu. 1 TRIM10
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Theoretical calculation and evaluation of n +^(240,242,244)Pu reactions 被引量:3
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作者 Hai-Rui Guo Yin-Lu Han Chong-Hai Cai 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第1期79-88,共10页
The nuclear data of n+^(240;242;244)Pu reactions for incident energy below 200 MeV are calculated and evaluated to meet the requirement in the design of an accelerator-driven subcritical system. The optical model is u... The nuclear data of n+^(240;242;244)Pu reactions for incident energy below 200 MeV are calculated and evaluated to meet the requirement in the design of an accelerator-driven subcritical system. The optical model is used to calculate the total, nonelastic, shape elastic cross sections, shape elastic scattering angular distributions, and transmission coefficients. The distorted-wave Born approximation is applied to calculate the direct inelastic scatterings to the discrete excited states. The nuclear reaction statistical models and fission theory are applied to describe neutron, proton, deuteron, triton, helium-3, alpha and c emissions, and fission consistently. The results thus obtained are compared with experimental data and the evaluated data obtained from ENDF/B-VII.1 and JENDL-4.0. 展开更多
关键词 n+240 242 244pu REACTIONS THEORETICAL calculation of NUCLEAR reaction NUCLEAR data for E≤200 MEV
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A HEVC Video Steganalysis Algorithm Based on PU Partition Modes 被引量:3
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作者 Zhonghao Li Laijing Meng +3 位作者 Shutong Xu Zhaohong Li Yunqing Shi Yuanchang Liang 《Computers, Materials & Continua》 SCIE EI 2019年第5期563-574,共12页
Steganalysis is a technique used for detecting the existence of secret information embedded into cover media such as images and videos.Currently,with the higher speed of the Internet,videos have become a kind of main ... Steganalysis is a technique used for detecting the existence of secret information embedded into cover media such as images and videos.Currently,with the higher speed of the Internet,videos have become a kind of main methods for transferring information.The latest video coding standard High Efficiency Video Coding(HEVC)shows better coding performance compared with the H.264/AVC standard published in the previous time.Therefore,since the HEVC was published,HEVC videos have been widely used as carriers of hidden information.In this paper,a steganalysis algorithm is proposed to detect the latest HEVC video steganography method which is based on the modification of Prediction Units(PU)partition modes.To detect the embedded data,All the PU partition modes are extracted from P pictures,and the probability of each PU partition mode in cover videos and stego videos is adopted as the classification feature.Furthermore,feature optimization is applied,that the 25-dimensional steganalysis feature has been reduced to the 3-dimensional feature.Then the Support Vector Machine(SVM)is used to identify stego videos.It is demonstrated in experimental results that the proposed steganalysis algorithm can effectively detect the stego videos,and much higher classification accuracy has been achieved compared with state-of-the-art work. 展开更多
关键词 Video steganalysis pu partition modes data hiding HEVC videos
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