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Polyethylene glycol has immunoprotective effects on sciatic allografts, but behavioral recovery and graft tolerance require neurorrhaphy and axonal fusion
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作者 Tyler A.Smith Liwen Zhou +6 位作者 Cameron L.Ghergherehchi Michelle Mikesh Cathy Z.Yang Haley O.Tucker JuliAnne Allgood Jared S.Bushman George D.Bittner 《Neural Regeneration Research》 SCIE CAS 2025年第4期1192-1206,共15页
Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal regeneration.Furthermore,such peripher... Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal regeneration.Furthermore,such peripheral nerve allografts undergo immunological rejection by the host immune system.In contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian degeneration.The relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this study.We hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral recovery.We examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal fusion.Ablation-type sciatic nerve injuries in outbred Sprague–Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host axons.Similar to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days postoperatively.Other morphological signs of rejection,such as collapsed Schwann cell basal lamina tubes,were absent in polyethylene glycol-fused peripheral nerve allografts but commonly observed in negative control and loose-sutured polyethylene glycol peripheral nerve allografts at 21 days postoperatively.Loose-sutured polyethylene glycol peripheral nerve allografts had more pro-inflammatory and less anti-inflammatory macrophages than negative control peripheral nerve allografts.While T cell counts were similarly high in loose-sutured-polyethylene glycol and negative control peripheral nerve allografts,loose-sutured polyethylene glycol peripheral nerve allografts expressed some cytokines/chemokines important for T cell activation at much lower levels at 14 days postoperatively.MHCI expression was elevated in loose-sutured polyethylene glycol peripheral nerve allografts,but MHCII expression was modestly lower compared to negative control at 21 days postoperatively.We conclude that,while polyethylene glycol per se reduces some immune responses of peripheral nerve allografts,successful polyethylene glycol-fusion repair of some axons is necessary to prevent Wallerian degeneration of those axons and immune rejection of peripheral nerve allografts,and produce recovery of sensory/motor functions and voluntary behaviors.Translation of polyethylene glycol-fusion technologies would produce a paradigm shift from the current clinical practice of waiting days to months to repair ablation peripheral nerve injuries. 展开更多
关键词 allograft rejection AXOTOMY macrophage MYELIN nerve repair polyethylene glycol(peg) sciatic nerve T cell transplantation Wallerian degeneration
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Vertically aligned montmorillonite aerogel-encapsulated polyethylene glycol with directional heat transfer paths for efficient solar thermal energy harvesting and storage
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作者 Qijing Guo Cong Guo +2 位作者 Hao Yi Feifei Jia Shaoxian Song 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期907-916,共10页
The conversion and storage of photothermal energy using phase change materials(PCMs)represent an optimal approach for harnessing clean and sustainable solar energy.Herein,we encapsulated polyethylene glycol(PEG)in mon... The conversion and storage of photothermal energy using phase change materials(PCMs)represent an optimal approach for harnessing clean and sustainable solar energy.Herein,we encapsulated polyethylene glycol(PEG)in montmorillonite aerogels(3D-Mt)through vacuum impregnation to prepare 3D-Mt/PEG composite PCMs.When used as a support matrix,3D-Mt can effectively prevent PEG leakage and act as a flame-retardant barrier to reduce the flammability of PEG.Simultaneously,3D-Mt/PEG demonstrates outstanding shape retention,increased thermal energy storage density,and commendable thermal and chemical stability.The phase transition enthalpy of 3D-Mt/PEG can reach 167.53 J/g and remains stable even after 50 heating-cooling cycles.Furthermore,the vertical sheet-like structure of 3D-Mt establishes directional heat transport channels,facilitating efficient phonon transfer.This configuration results in highly anisotropic thermal conductivities that ensure swift thermal responses and efficient heat conduction.This study addresses the shortcomings of PCMs,including the issues of leakage and inadequate flame retardancy.It achieves the development and design of 3D-Mt/PEG with ultrahigh strength,superior flame retardancy,and directional heat transfer.Therefore,this work offers a design strategy for the preparation of high-performance composite PCMs.The 3D-Mt/PEG with vertically aligned and well-ordered array structure developed in this research shows great potential for thermal management and photothermal conversion applications. 展开更多
关键词 montmorillonite aerogel polyethylene glycol phase change materials solar thermal energy storage flame retardant
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Hyponatremic encephalopathy due to polyethylene glycol-based bowel preparation for colonoscopy:A case report 被引量:1
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作者 Yuan Zhao Hai-Sheng Dong 《World Journal of Clinical Cases》 SCIE 2023年第1期187-192,共6页
BACKGROUND Adequate bowel preparation is critical for colonoscopy screening.At present,the most widely used intestinal cleaner recommended at home and abroad is Polyethylene glycol(PEG).Intestinal cleansers can cause ... BACKGROUND Adequate bowel preparation is critical for colonoscopy screening.At present,the most widely used intestinal cleaner recommended at home and abroad is Polyethylene glycol(PEG).Intestinal cleansers can cause electrolyte disturbances and hyponatremia.However,hyponatremic encephalopathy due to hyponatremia induced by PEG solution,although rare,can lead to serious irreversible sequelae and even death.CASE SUMMARY In this report,we discuss a case of neurological dysfunction due to hyponatremia,also known as hyponatremic encephalopathy,observed in a 63-year-old woman who underwent PEG-based bowel preparation for colonoscopy.She was eventually transferred to our intensive care unit for treatment due to her Glasgow Coma Scale score of 9/15(Eye opening 2;Verbal response 1;Motor response 6)and abnormal laboratory tests.CONCLUSION Physicians should be thoroughly familiarized with the patient’s history before prescribing PEG for bowel preparation,and timely identification of patients with hyponatremic encephalopathy is essential as delayed treatment is associated with poor neurological outcomes.An intravenous infusion of 3%sodium chloride is recommended at the onset of early symptoms.The goal of treatment is to adequately treat cerebral edema while avoiding serum sodium correction beyond 15 to 20 m Eq/L within 48 h of treatment to prevent osmotic demyelination syndrome. 展开更多
关键词 polyethylene glycol Intestinal preparation Hyponatremic encephalopathy HYPONATREMIA BRAIN Case report
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Polyethylene glycol crosslinked decellularized single liver lobe scaffolds with vascular endothelial growth factor promotes angiogenesis in vivo
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作者 Jian-Se Zhang Zhi-Bin Wang +5 位作者 Zhi-Zhen Lai Jing-Wen Yang Wen-Jing Song Yu-Bing Wei Jin Mei Jian-Guang Wang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第6期622-631,共10页
Background: Improving the mechanical properties and angiogenesis of acellular scaffolds before transplantation is an important challenge facing the development of acellular liver grafts. The present study aimed to eva... Background: Improving the mechanical properties and angiogenesis of acellular scaffolds before transplantation is an important challenge facing the development of acellular liver grafts. The present study aimed to evaluate the cytotoxicity and angiogenesis of polyethylene glycol(PEG) crosslinked decellularized single liver lobe scaffolds(DLSs), and establish its suitability as a graft for long-term liver tissue engineering. Methods: Using mercaptoacrylate produced by the Michael addition reaction, DLSs were first modified using N-succinimidyl S-acetylthioacetate(SATA), followed by cross-linking with PEG as well as vascular endothelial growth factor(VEGF). The optimal concentration of agents and time of the individual steps were identified in this procedure through biomechanical testing and morphological analysis. Subsequently, human umbilical vein endothelial cells(HUVECs) were seeded on the PEG crosslinked scaffolds to detect the proliferation and viability of cells. The scaffolds were then transplanted into the subcutaneous tissue of Sprague-Dawley rats to evaluate angiogenesis. In addition, the average number of blood vessels was evaluated in the grafts with or without PEG at days 7, 14, and 21 after implantation. Results: The PEG crosslinked DLS maintained their three-dimensional structure and were more translucent after decellularization than native DLS, which presented a denser and more porous network structure. The results for Young’s modulus proved that the mechanical properties of 0.5 PEG crosslinked DLS were the best and close to that of native livers. The PEG-VEGF-DLS could better promote cell proliferation and differentiation of HUVECs compared with the groups without PEG cross-linking. Importantly, the average density of blood vessels was higher in the PEG-VEGF-DLS than that in other groups at days 7, 14, and 21 after implantation in vivo. Conclusions: The PEG crosslinked DLS with VEGF could improve the biomechanical properties of native DLS, and most importantly, their lack of cytotoxicity provides a new route to promote the proliferation of cells in vitro and angiogenesis in vivo in liver tissue engineering. 展开更多
关键词 DECELLULARIZATION Single liver lobe polyethylene glycol ANGIOGENESIS Liver tissue engineering
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高增塑PEG弹性体网络结构与力学性能关系
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作者 王耀霄 王小英 +2 位作者 陈晨 谭茱匀 周星 《含能材料》 EI CAS CSCD 北大核心 2024年第2期204-210,共7页
为了建立硝酸酯增塑聚醚(NEPE)推进剂中高增塑的聚乙二醇(PEG)基聚氨酯的微观结构与宏观力学性能的相关性,以缩二脲三异氰酸酯(N⁃100)为多官能度固化剂,与硝酸酯增塑的PEG混胶固化,制备了固化参数1.2~1.7的高增塑PEG弹性体。采用单轴拉... 为了建立硝酸酯增塑聚醚(NEPE)推进剂中高增塑的聚乙二醇(PEG)基聚氨酯的微观结构与宏观力学性能的相关性,以缩二脲三异氰酸酯(N⁃100)为多官能度固化剂,与硝酸酯增塑的PEG混胶固化,制备了固化参数1.2~1.7的高增塑PEG弹性体。采用单轴拉伸、X射线衍射、低场核磁共振、平衡溶胀测试方法,对PEG弹性体交联网络微观结构特征进行研究,并基于低场核磁结果,分析了不同网链结构对高增塑PEG弹性体力学性能的影响。结果表明:由于高增塑的特性,PEG弹性体为非晶态,悬尾链与自由链总比例大于85%,交联网络结构完整度低,弹性体呈高伸长率、低抗拉强度和低初始模量的特点。弹性体抗拉强度和初始模量均与交联链网链密度呈正相关;随着物理暂时缠结网链密度的升高,最大伸长率先升高后降低。固化参数为1.6的CU⁃5弹性体交联网络最完整,抗拉强度为0.80 MPa,最大伸长率为1456%,力学性能最优。2种方法测得的网链密度满足低场核磁法交联链密度(νL,A)<溶胀法网链密度(νs)<低场核磁法交联链与悬尾链总网链密度(ν_(L,A+B))的大小关系。 展开更多
关键词 聚乙二醇聚氨酯弹性体 交联网络结构 力学性能 低场核磁
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Polyethylene glycol (PEG) as a benign solvent for Knoevenagel condensation 被引量:7
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作者 Yang Liu Jun Liang Xiu Hong Liu Ji Cai Fan Zhi Cai Shang 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第9期1043-1046,共4页
有活跃甲又化合物的芳香的醛的 Knoevenagel 冷凝作用作为催化剂在房间温度在聚乙烯乙二醇高效地继续了 l 脯氨酸。收益高,产品主导地有电子异构体。包含 l 脯氨酸的聚乙烯乙二醇能被再循环并且再使用为若干次没有显著地在生产率减少。
关键词 聚氧乙烯 L脯氨酸 催化剂 生产力
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PEG辅助合成片层结构钛硅分子筛催化氧化脱硫性能研究
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作者 党阳 王海彦 任铁强 《精细石油化工》 CAS 2024年第3期13-18,共6页
以正硅酸乙酯为硅源、钛酸四丁酯为钛源、四丙基氢氧化铵为模板剂,采用聚乙二醇作为结构导向剂制备了片层结构钛硅分子筛,进行了表征和分析。结果表明:聚乙二醇辅助合成的钛硅分子筛(PTS)具有明显的片层结构、较高的比表面积和多级孔道... 以正硅酸乙酯为硅源、钛酸四丁酯为钛源、四丙基氢氧化铵为模板剂,采用聚乙二醇作为结构导向剂制备了片层结构钛硅分子筛,进行了表征和分析。结果表明:聚乙二醇辅助合成的钛硅分子筛(PTS)具有明显的片层结构、较高的比表面积和多级孔道结构;以1 000 mg/L噻吩-正辛烷为模拟油、H_(2)O_(2)为氧化剂进行脱硫性能实验,在相同脱硫时间内PTS-30(硅钛比为30)对噻吩脱除性能较传统钛硅分子筛提高近10%,循环7次后PTS-30分子筛脱硫性能仍保持60.2%。 展开更多
关键词 钛硅分子筛 硅钛比 聚乙二醇 氧化脱硫
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Anaphylactic shock induced by polyethylene glycol after bowel preparation for the colorectal cancer surgery:A case report
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作者 Go Woon Park Nahyeon Park +2 位作者 Jung Cheol Kuk Eung Jin Shin Dae Ro Lim 《World Journal of Clinical Cases》 SCIE 2023年第23期5589-5594,共6页
BACKGROUND Polyethylene glycol(PEG)is widely used as an additive because of its hydrophilic and chemically inert properties.However,there are been increasing reports of PEG allergies,including anaphylaxis,although the... BACKGROUND Polyethylene glycol(PEG)is widely used as an additive because of its hydrophilic and chemically inert properties.However,there are been increasing reports of PEG allergies,including anaphylaxis,although they are still rare.This case report aims to raise awareness,that the commonly used bowel cleansing agent containing PEG can cause serious allergic reactions.CASE SUMMARY Prior to surgery for sigmoid colon cancer,a 63-year-old man was prescribed a bowel cleansing agent containing PEG.Within 30 min of ingestion,he developed symptoms of anaphylactic shock and did not respond to initial intramuscular epinephrine injection.Under diagnosis of anaphylaxis to PEG,he was stabilized with fluid hydration and continuous norepinephrine infusion.CONCLUSION While allergic reactions to PEG are rare,they can be life-threatening.Therefore,it is crucial for clinicians to be aware of this possibility and to diagnose and resuscitate patients immediately. 展开更多
关键词 polyethylene glycol ANAPHYLAXIS Sigmoid colon cancer Bowel preparation Case report
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聚氨酯绷带用PEG-CL-LA共聚物的制备及其性能的研究
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作者 虞远忠 夏浙安 +1 位作者 陈伶俐 叶炜 《中国胶粘剂》 CAS 2024年第4期35-40,共6页
以辛酸亚锡为催化剂,聚乙二醇(PEG)为起始剂,ε-己内酯(CL)和乳酸(LA)为原料,在170℃和高真空的条件下直接缩聚合成了不同数量CL单元与LA单元的二元醇共聚物(PLCA)。PLCA与过量的4,4’-二苯基甲烷二异氰酸酯(MDI-100)及少量叔胺类催化... 以辛酸亚锡为催化剂,聚乙二醇(PEG)为起始剂,ε-己内酯(CL)和乳酸(LA)为原料,在170℃和高真空的条件下直接缩聚合成了不同数量CL单元与LA单元的二元醇共聚物(PLCA)。PLCA与过量的4,4’-二苯基甲烷二异氰酸酯(MDI-100)及少量叔胺类催化剂混合,在70℃反应,得到异氰酸酯封端的共聚物混合胶体(PLCA-PU),并涂覆在聚酯多孔编织带上制备出聚氨酯绷带。保持PEG的量,改变CL和LA的比例和异氰酸酯的量,得到一系列的PLCA和PLCA-PU。对它们的结构进行了分析,并对聚氨酯绷带的固化时间、径向压缩力值进行了测试。研究结果表明:成功制备了PLCA和PLCA-PU;当R=5、n(PEG)∶n(CL)∶n(LA)=1∶6∶7时,PLCA-PU制备的绷带的固化时间为383 s,压缩力值最高能达到19.4 N;选用合适的物料配比可以满足绷带尽快固化、具有合适刚性强度的要求。 展开更多
关键词 聚乙二醇 聚氨酯绷带 Ε-己内酯 乳酸
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星型PLLA-PEG嵌段共聚物纤维膜的制备及其亲水性能
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作者 邢东风 李雲环 +3 位作者 高宇 王福兴 富强 金达莱 《现代纺织技术》 北大核心 2024年第3期45-52,共8页
星型结构相比较于线型结构具有更稳定的形态和更优异的力学性能。选用季戊四醇(PET)为引发剂,辛酸亚锡(Sn(Oct)_(2))为催化剂,通过L-丙交酯(L-LA)的开环聚合(ROP)制备星型端羟基聚(L-丙交酯)(s-PLLA),并与聚乙二醇(PEG,相对分子质量为10... 星型结构相比较于线型结构具有更稳定的形态和更优异的力学性能。选用季戊四醇(PET)为引发剂,辛酸亚锡(Sn(Oct)_(2))为催化剂,通过L-丙交酯(L-LA)的开环聚合(ROP)制备星型端羟基聚(L-丙交酯)(s-PLLA),并与聚乙二醇(PEG,相对分子质量为1000)缩合制备四臂星型聚(L-丙交酯)-聚乙二醇共聚物(s-PLLA-PEG)。采用^(1)H-核磁共振、^(13)C-核磁共振、傅里叶变换红外光谱、超高效聚合物色谱仪对产物进行表征,并用静电纺丝技术制备s-PLLA-PEG纤维膜进行亲水性能测试。结果表明:s-PLLA-PEG共聚物被成功合成;相对于s-PLLA,s-PLLA-PEG的熔体温度和玻璃化转变温度降低,柔韧性得到改善,韧性增强;s-PLLA-PEG纤维膜对水的接触角是84.10°,随着时间的推移,接触角逐渐减小,最终水被纤维膜完全吸收,相比较s-PLLA纤维膜具有更强的亲水性。该研究表明,PEG嵌段的引入可以有效改善s-PLLA纤维膜的亲水性,展现出静电纺s-PLLA-PEG纤维膜在医用敷料领域的应用前景。 展开更多
关键词 星型 聚(L-丙交酯)-聚乙二醇共聚物 静电纺丝 亲水性
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PEG降低HIV第四代试剂检测假阳性干扰的研究
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作者 阳冬冬 穆银玉 +2 位作者 张日伊 李静 徐琳 《中国现代医生》 2024年第13期40-42,59,共4页
目的探讨聚乙二醇(polyethylene glycol,PEG)沉淀法降低化学发光法人类免疫缺陷病毒(human immunodeficiency virus,HIV)第四代试剂检测假阳性干扰的研究。方法选取2022年1月至6月就诊于宁波市医疗中心李惠利医院的门诊和住院患者109例... 目的探讨聚乙二醇(polyethylene glycol,PEG)沉淀法降低化学发光法人类免疫缺陷病毒(human immunodeficiency virus,HIV)第四代试剂检测假阳性干扰的研究。方法选取2022年1月至6月就诊于宁波市医疗中心李惠利医院的门诊和住院患者109例,经化学发光法初筛阳性的样本经蛋白质印迹法确证实验,确证真阳性样本20例、假阳性样本89例。根据是否添加处理剂将假阳性样本分为三组:无PEG沉淀组(无特殊处理,89例)、PEG沉淀组(PEG沉淀处理,89例)和对照组(生理盐水处理,89例),离心后测定上清液HIV抗原/抗体(antigen/antibody,Ag/Ab)水平,比较不同处理方法前后HIV Ag/Ab水平的差异及回收率。结果处理后,PEG沉淀组和对照组的HIV Ag/Ab浓度显著均低于无PEG沉淀组(P<0.001)。处理后,PEG沉淀组阳性3例,对照组阳性56例,阳性率均显著低于无PEG沉淀组(P<0.001);PEG沉淀组的回收率为4.92(2.12,12.69)%,对照组的回收率为65.28(18.04,91.28)%。不论PEG处理还是生理盐水处理,真阳性样本的回收率均>50%。结论PEG沉淀法可有效降低化学发光法HIV第四代试剂检测的假阳性干扰,且对真阳性样本无影响。 展开更多
关键词 人类免疫缺陷病毒 聚乙二醇 化学发光法 假阳性 干扰
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PEG/漂珠复合相变材料的表征及性能研究
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作者 程作栋 张家玮 +3 位作者 余阳 王向阳 刘生玮 郭月霞 《交通科学与工程》 2024年第2期8-16,27,共10页
为了研发适用于高温环境下沥青路面的复合相变材料,本研究以PEG2000作为相变材料,漂珠作为载体,利用PEG2000优良的相变特性及漂珠的高强度特性,制备出一种高强度且耐高温的复合相变材料(composite phase change materials,CPCMs)。制备... 为了研发适用于高温环境下沥青路面的复合相变材料,本研究以PEG2000作为相变材料,漂珠作为载体,利用PEG2000优良的相变特性及漂珠的高强度特性,制备出一种高强度且耐高温的复合相变材料(composite phase change materials,CPCMs)。制备的CPCMs在相变储热性能上表现较好,同时具有优良的化学稳定性、兼容性及热稳定性。当CPCMs的掺量达到60%时,测温试件之间的最高温差仅为2.8℃,峰值温度出现的时间延迟了2.1 min,对路用性能也产生了不利影响。因此,适量CPCMs能够有效调控沥青混合料温度。该研究结果为沥青路面的降温调控提供了参考。 展开更多
关键词 沥青路面 复合相变材料 peg 漂珠 路用性能 降温调控
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Effect of Free Cells and Additional Supporting Material on Performance of Polyethylene Glycol (PEG)-Pellet Reactor to Treat NH4-N Contaminated Groundwater
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作者 Wilawan Khanitchaidecha Tatsuo Sumino Futaba Kazama 《Journal of Water Resource and Protection》 2011年第1期12-21,共10页
To study the effect of free cells (suspended bacteria) on performance of entrapped bacteria system (i.e. polyethylene glycol (PEG)-pellet reactor) to treat NH4-N contaminated groundwater, two PEG-pellet reactors with ... To study the effect of free cells (suspended bacteria) on performance of entrapped bacteria system (i.e. polyethylene glycol (PEG)-pellet reactor) to treat NH4-N contaminated groundwater, two PEG-pellet reactors with a lot of free cells - Reactor A containing PEG-pellet and Reactor B containing PEG-pellet and supporting material - and the another control reactor without free cells (Reactor C) were set-up. Three reactors were operated under various NH4-N concentrations (40-60 mg/L) and various temperatures (5-25oC). The results show that the free cells effected on the NH4-N removal efficiency significantly. The free cells developed to be a biofilm layer on the pellet surface for Reactor A, the biofilm layer caused the decreasing NH4-N diffusion and incomplete nitrification eventually. On the other hand, most free cells attached to the supporting material for Reactor B. Although the NH4-N could diffuse properly, the free cells consuming acetate caused the added acetate was insufficient for complete denitrification. However, the results suggest that the supporting material could reduce the effect of free cells on the reactor performance at low temperature as indicated by 1) higher efficiency and 2) lower activation energy (Ea) for nitrification and denitrification in Reactor B than Reactor A. 展开更多
关键词 NH4-N removal Nitrification and Denitrification Groundwater Purification polyethylene glycol (peg)-Pellet SUPPORTING MATERIAL Free CELLS
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Effect of Silicon (Si) Application on Phoenix dactylifera L. Growth under Drought Stress Induced by Polyethylene Glycol (PEG) in Vitro
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作者 Ahmed Madi Waheed Al-Mayahi 《American Journal of Plant Sciences》 2016年第13期1711-1728,共18页
This study was carried out to investigate the effects of silicon (Si) 3.6 mM (as calcium silicate) under drought stress induced by polyethylene glycol “PEG” at 15% (MW 8000), in addition to the control treatment on ... This study was carried out to investigate the effects of silicon (Si) 3.6 mM (as calcium silicate) under drought stress induced by polyethylene glycol “PEG” at 15% (MW 8000), in addition to the control treatment on growth and some biochemical constituents of date palm cv. Barhee cultured in vitro. Drought stress (15% PEG) depressed the growth of shoot and decreased protein content and chlorophyll concentration. Addition of 3.6 mM Si could improve the growth of shoot and increase the protein content and leaf chlorophyll concentrations of stressed plants. The inclusion of Si to the PEG containing medium significantly increased the catalase (CAT) and superoxide dismutase (SOD) activity in regenerated shoot, compared to other treatments. As well as drought stress 15% PEG induced significant accumulation of shoots proline, which were decreased by added silicon. Moreover, the results were also supported by the observation that PEG stress-induced decrease the response percentage of root induction and root lengths was reversed by added silicon. Addition of Si obviously significantly increased the wax content in leaves, response percentage of root induction and root lengths of plantlets under drought stress. The results of this study indicate that the application of silicon improved growth attributes, effectively mitigate the adverse effect of drought, and increase tolerance of date palm plants for drought stress during the course of date palm tissue cultures. 展开更多
关键词 Silicon (Si) Drought Stress polyethylene glycol (peg) Tissue Culturing Antioxidant Activity Waxy Layer
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载多西紫杉醇Poloxamer188复合PEG100k电纺纤维的表征
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作者 邱志越 王瑛颖 +1 位作者 吕蕴麒 王浩 《锦州医科大学学报》 CAS 2024年第2期9-17,共9页
目的考察Poloxamer188复合PEG100k电纺纤维的形态及载多西紫杉醇后的形态、材料复合,以及载药纤维水化后药物增溶和包裹情况。方法将多西紫杉醇、Poloxamer188和PEG100k溶解在二氯甲烷中形成共溶液后静电纺丝。考察了Poloxamer188的复... 目的考察Poloxamer188复合PEG100k电纺纤维的形态及载多西紫杉醇后的形态、材料复合,以及载药纤维水化后药物增溶和包裹情况。方法将多西紫杉醇、Poloxamer188和PEG100k溶解在二氯甲烷中形成共溶液后静电纺丝。考察了Poloxamer188的复合量从10%直至100%以及多西紫杉醇载量为5%、10%、15%、20%等情况。扫描电子显微镜考察纤维形态、差示热分析、热重分析和X-射线衍射考察材料复合及载药。分别在纯水/载药纤维为40/100和5/100(V/m,mL/mg)两种水化条件下水化载药纤维,前者得到液体后者溶胀。在10000 r/min下离心3 min后,前者得到固体沉淀和上清液,后者得到水凝胶沉淀和上清液。采用高效液相色谱-紫外分光光度法测定两种不同处理方法下上清液中多西紫杉醇的含量,分别计算药物增溶百分率和渗漏百分率。结果所得电纺纤维直径均小于5μm,直径较为均一且完全无珠子结构存在。物质之间发生复合,但是在纤维表面有PEG100k片段的衍射峰。水化后所得的液体,5%多西紫杉醇载量的纤维药物增溶百分率最高,大部分样品在70%~80%之间,载药量升高至10%、15%时,增溶百分率降至20%以下,载药量升高至20%时,大部分样品增溶量接近于0。5%载药量系列纤维随着Poloxamer188复合量的增高药物增溶百分率先升高后降低,F-5%-40%中多西紫杉醇的增溶百分率可达80%。多西紫杉醇载量为5%时,水化后所得的凝胶渗漏百分率大于其他载药量的情况,但是未超过5%的渗漏百分率,载药量为10%、15%、20%时,渗漏百分率均小于2%。结论通过均相溶液静电纺丝技术可以制备形态较为理想的载多西紫杉醇PEG100k纤维,水化后纤维中的药物增溶量可以达到药典标准,多西紫杉醇载量及Poloxamer188复合量对药物增溶量影响明显,且所得水化凝胶渗漏率很低。 展开更多
关键词 多西紫杉醇 电纺纤维 聚乙二醇 泊洛沙姆 增溶
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SA/AKP/PEG 4000神经导管的制备与表征
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作者 丁铭飞 郭静 +2 位作者 张一航 李政 田钧 《大连工业大学学报》 CAS 2024年第2期147-151,共5页
将神经导管植入损伤的神经组织处可促进神经恢复。受成本与技术的限制,湿法成型难以批量生产孔径大小和分布相对均匀的神经导管。为连续制备孔径大小及分布均匀的神经导管,以海藻酸钠、磷虾蛋白生物可降解材料作为基体,以PEG 4000作为... 将神经导管植入损伤的神经组织处可促进神经恢复。受成本与技术的限制,湿法成型难以批量生产孔径大小和分布相对均匀的神经导管。为连续制备孔径大小及分布均匀的神经导管,以海藻酸钠、磷虾蛋白生物可降解材料作为基体,以PEG 4000作为致孔剂,通过低温湿法成型结合冷冻干燥方法制备了多孔神经导管支架材料,表征了材料的结构和性质。结果表明,PEG 4000有降低溶液的黏度、提高导管热稳定性的作用,导管截面具有蜂窝状孔洞结构,其孔径在10~20μm,最大孔隙率达到97%。导管为亲水材料,其吸液性能随PEG 4000质量分数呈先增大后减小的趋势,PEG 4000质量分数为30%~40%时导管的吸液性能达到1 417%。 展开更多
关键词 海藻酸钠 聚乙二醇 神经导管 低温凝固
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PEG-2000添加量对Pr_(x)Zr_(1-x)O_(2-δ)催化氧化NO活性的影响
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作者 龚宥精 田文珊 +2 位作者 赵光垒 贾丽娟 刘天成 《现代化工》 CAS CSCD 北大核心 2024年第6期134-139,共6页
采用溶胶-凝胶法制备了Pr_(x)Zr_(1-x)O_(2-δ)催化剂,并用于NO催化氧化。以聚乙二醇-2000(PEG-2000)为模板剂对催化剂进行改性,研究了不同模板剂添加质量分数对NO催化氧化活性的影响。结果表明,催化剂活性随PEG-2000添加质量分数的增... 采用溶胶-凝胶法制备了Pr_(x)Zr_(1-x)O_(2-δ)催化剂,并用于NO催化氧化。以聚乙二醇-2000(PEG-2000)为模板剂对催化剂进行改性,研究了不同模板剂添加质量分数对NO催化氧化活性的影响。结果表明,催化剂活性随PEG-2000添加质量分数的增加而降低;在300℃、PEG-2000添加质量分数为2%时,Pr_(x)Zr_(1-x)O_(2-δ)的催化活性最高,NO转化率达到了94.81%。利用XRD、SEM、N2吸附-脱附、XPS及FT-IR对催化剂进行表征,结果表明,模板剂添加质量分数的变化不会改变催化剂Pr_(2)Zr_(2)O_(7)晶型;催化剂为介孔结构,质量分数为2%时的比表面积和孔容最大,有利于催化氧化NO。此外,模板剂质量分数的增加会增强催化剂的亲水性。 展开更多
关键词 聚乙二醇 催化氧化 氮氧化物 Pr_(x)Zr_(1-x)O_(2-δ) 溶胶-凝胶法
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不同分子质量PEG对水泥基材料性能的影响 被引量:1
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作者 孔德玉 孙浩铨 +3 位作者 王蓉 曾法军 张永军 陈元朋 《新型建筑材料》 2023年第2期74-78,共5页
研究了相对分子质量分别为1000和6000的2种聚乙二醇(分别记为P10和P60)对水泥基材料性能的影响。结果表明:掺P60对水泥砂浆的增黏效果明显优于掺P10。掺P60对水泥砂浆3 d和28 d抗折、抗压强度有明显增强作用,但养护至90 d时,其增强效果... 研究了相对分子质量分别为1000和6000的2种聚乙二醇(分别记为P10和P60)对水泥基材料性能的影响。结果表明:掺P60对水泥砂浆的增黏效果明显优于掺P10。掺P60对水泥砂浆3 d和28 d抗折、抗压强度有明显增强作用,但养护至90 d时,其增强效果已不明显;掺P10则在所有龄期对水泥砂浆均无明显增强效果。掺聚乙二醇(PEG)可一定程度上减小水泥砂浆在6.0mol/L氯化铵溶液中浸泡的强度损失率,但其对砂浆抗溶蚀性能和抗氯离子渗透性能均有不利影响。掺P10对水泥砂浆抗氯离子渗透性能的不利影响明显小于掺P60,其原因是掺P10对硬化水泥石毛细孔和有害孔的影响较小所致。 展开更多
关键词 聚乙二醇(peg) 水泥基材料 力学性能 耐久性 微观结构
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EPEG大单体聚合升温与其合成减水剂性能的关联
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作者 裴继凯 王越 +4 位作者 陈广明 刘学明 任建国 张慧爱 王自为 《混凝土》 CAS 北大核心 2023年第7期66-69,74,共5页
研究了几种乙烯氧基聚乙二醇EPEG大单体与丙烯酸接枝共聚合成聚羧酸减水剂,在相同条件下进行聚合反应,对EPEG型聚羧酸减水剂合成过程进行升温测试及聚合过程分析,使用凝胶渗透色谱法表征产物的相对平均分子量、分子量分布指数及转化率... 研究了几种乙烯氧基聚乙二醇EPEG大单体与丙烯酸接枝共聚合成聚羧酸减水剂,在相同条件下进行聚合反应,对EPEG型聚羧酸减水剂合成过程进行升温测试及聚合过程分析,使用凝胶渗透色谱法表征产物的相对平均分子量、分子量分布指数及转化率等结构参数,最后测试产物的水泥净浆流动度、混凝土材料的流动性以及硬化后的力学性能。试验结果表明:不同EPEG大单体聚合活性差异很大,大单体聚合快速升温期在15 min以内的聚合效果好。EPEG聚合放热升温曲线可以作为评价EPEG大单体活性的一种简单有效的方法,EPEG大单体聚合升温曲线与其合成聚羧酸减水剂应用性能二者间有很好的关联性。 展开更多
关键词 单体活性 丙烯酸-乙烯氧基聚乙二醇接枝共聚物(AA-g-Epeg) 聚合升温 Epeg型聚羧酸减水剂 混凝土
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Bisacodyl plus split 2-L polyethylene glycol-citrate-simethicone improves quality of bowel preparation before screening colonoscopy 被引量:10
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作者 Flavio Valiante Angelo Bellumat +1 位作者 Manuela De Bona Michele De Boni 《World Journal of Gastroenterology》 SCIE CAS 2013年第33期5493-5499,共7页
AIM:To compare the bowel cleansing efficacy,tolerability and acceptability of split 2-L polyethylene glycol(PEG)-citrate-simethicone(PEG-CS)plus bisacodyl(BIS)vs 4-L PEG for fecal occult blood test-positive screening ... AIM:To compare the bowel cleansing efficacy,tolerability and acceptability of split 2-L polyethylene glycol(PEG)-citrate-simethicone(PEG-CS)plus bisacodyl(BIS)vs 4-L PEG for fecal occult blood test-positive screening colonoscopy.METHODS:This was a randomised,observer-blind comparative study.Two hundred and sixty-four subjects underwent screening colonoscopy(mean age 62.5±7.4years,male 61.7%).The primary objective of the study was to compare the bowel cleansing efficacy of the two preparations.Interventions:BIS plus PEG-CS:3 tablets of 5-mg BIS at 16:00,PEG-CS 1-L at 19:00 and 1-L at7:00,4-L PEG:3-L at 17:00,and 1-L at 7:00.Colonoscopy was carried out after 11:00,at least 3 h after the completion of bowel preparation.Bowel cleansing was evaluated using the Harefield Cleansing Scale.RESULTS:Bowel preparation was successful for 92.8%of subjects in the PEG-CS group and for 92.1%of subjects in the 4-L PEG(RR=1.01;95%CI:0.94-1.08).BIS+PEG-CS was better tolerated than 4-L PEG.A greater rate of patients in the BIS+PEG-CS group had no difficulty and/or were willing to repeat the same preparation compared to split-dose 4-L PEG group.Subjects in the BIS+PEG-CS group rated the prep as good or satisfactory in 90.6%as compared to 77%in the 4-L PEG(P=0.003).Subjects receiving BIS+PEGCS stated they fully adhered to instructions drinking all the 2-L solution in 97.1%compared with 87.3%in the4-L PEG(P=0.003).CONCLUSION:BIS plus split 2-L PEG-CS was as effective as but better tolerated and accepted than split4-L PEG for screening colonoscopy.This new procedure may increase the positive attitude and participation to colorectal cancer screening colonoscopy. 展开更多
关键词 COLONOSCOPY Colon CLEANSING Bowel preparations polyethylene glycol SIMETHICONE BISACODYL
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