搜索到1156篇“ CROSSLINK“的相关文章
交联密度和交联键分布对NR/TBIR硫化胶应用性能的影响
2024年
通过在普通硫磺硫化体系(CV)、半有效硫磺硫化体系(SEV)和有效硫磺硫化体系(EV)中变化促进剂/硫磺用量调控硫化胶的交联密度和交联键分布,研究其对天然橡胶(NR)和NR/反式丁戊橡胶(TBIR)硫化胶应用性能的影响。结果表明,交联密度是影响硫化胶应用性能的关键,在CV、SEV和EV硫化体系中提高交联密度,NR和NR/TBIR硫化胶的硬度、定伸应力、耐磨耗性能逐渐提高,拉断伸长率、耐疲劳性能和滚动阻力逐渐降低。在同样的交联密度下调控交联键类型由多硫键向单硫键和双硫键转变,NR和NR/TBIR硫化胶的耐疲劳性能显著下降。在同样的交联密度和交联键分布下,NR/TBIR硫化胶相比NR硫化胶均具有更优异的耐磨耗性能和耐疲劳性能以及更低的滚动阻力,相比NR硫化胶,降低交联密度会使NR/TBIR硫化胶在耐磨耗性能上具有更大优势,降低交联密度、提高多硫键比例会使NR/TBIR硫化胶在耐疲劳性能上具有更大优势。
王浩李兰阁刘晓孟夏王日国
关键词:交联密度耐疲劳性能
Ultraclean transfer of graphene by mechanically exfoliating polymer with modified crosslink density
2024年
The transfer of graphene from metallic substrates onto application-specific substrates is usually inevitable for the applications of high-quality graphene films derived from chemical vapour deposition(CVD)approaches.Commonly used to support the graphene films during the transfer,the coating of the polymer would produce the surface contaminations and hinder the industrially compatible transfer.In this work,through the thermal imidization of polyamide acid(PAA)to polyimide(PI)and tuning of the concentration of dangling chains,we achieved the ultraclean and crack-free transfer of graphene wafers with high electronic quality.The resulting contamination-free and hydrophilic surface also enabled the observed improved cell viability in a biomedical applications.By avoiding aqueous etching or the usage of strong bases,our proposed transfer method is industrially compatible for batch transfer of graphene films towards the real applications.
Qi LuJiawei YangChaofan ZhouZhaoning HuSaiyu BuBingbing GuoYixuan ZhaoJunhao LiaoMingpeng ShangGe ChenKaicheng JiaJianbo YinQiang ZengLi LinZhongfan Liu
In situ crosslink polymerization induced long-lived multicolor supramolecular hydrogel based on modifiedβ-cyclodextrin
2024年
The construction of hydrogels with good mechanical properties and phosphorescent properties is full of challenges.Herein,we report a supramolecular phosphorescent hydrogel with long lifetime,high tensile strength and self-healing property,which can be easily constructed through in-situ thermalinitiated polymerization of isocyanatoethyl acrylate-modifiedβ-cyclodextrin(β-CD-DA)and acrylatemodified adamantane(Ad-DA),acrylic acid(AA),followed by the non-covalent association with carbon dots(CNDs).The lifetime of phosphorescent hydrogel can reach 1261 ms at room temperature,and the quantum yield is 11%.Importantly,through the efficient triplet to singlet Förster resonance energy transfer(TS-FRET),the phosphorescent hydrogel shows the good phosphorescence energy transfer property for organic dyes Rhodamine B and Eosin Y with the delayed fluorescence lifetime up to 730 ms and 585 ms as well as the energy transfer efficiency(Φ_(ET))up to 99.9%and 99.3%,respectively.Moreover,owing to the host-guest interactions betweenβ-CD-DA and Ad-DA,the three-dimensional cross-linked network phosphorescent hydrogel can be easily stretched to 18 times of its original length,and can achieve self-healing of the cut surfaces within 30 min.These results will expand the scope of phosphorescent materials and provide new ideas and opportunities for materials science.
Yonghui SunLinnan JiangYong ChenYu Liu
关键词:CYCLODEXTRIN
A Fast Insertion Tabu Search with Conflict-Avoidance Heuristic for the Multisatellite Multimode Crosslink Scheduling Problem被引量:1
2024年
An agile earth-observing satellite equipped with multimode cameras capable of transmitting observation data to other satellites is developed to rapidly respond to requests with multiple observation modes.This gives rise to the Multisatellite Multimode Crosslink Scheduling(MMCS)problem,which involves allocating observation requests to agile satellites,selecting appropriate timing and observation modes for the requests,and transmitting the data to the ground station via the satellite communication system.Herein,a mixed integer programming model is introduced to include all complex time and operation constraints.To solve the MMCS problem,a two-stage heuristic method,called Fast insertion Tabu Search with Conflict-avoidance(FTS-C)heuristic,is developed.In the first stage,a conflict-avoidance insertion algorithm is designed to generate a high-quality initial solution by considering the requests transmission and download.Further,the tabu search-based second stage optimizes the initial solution.Finally,an extensive empirical study based on a real-world situation demonstrates that FTS-C can generate a solution with higher quality in less time than other state-of-the-art algorithms and the CPLEX solver.
Weiyi YangLei HeXiaolu LiuWeican MengYingwu Chen
Crosslink among cyclin-dependent kinase 9,ATP binding cassette transporter G2 and Beclin 1 in colorectal cancer
2024年
Colorectal cancer(CRC)ranks third in the number of cancers mainly because of the inability to diagnose it at an early stage.The pathogenesis of CRC is complicated,which is the result of the complex interaction of multiple genetic and environmental factors.Currently,one of the main treatments for CRC is chemotherapy.But the primary cause of CRC treatment failure is drug resistance.The expression of cyclin-dependent kinase 9(CDK9)was correlated with elevated autophagy levels in colon cancer,and high expression of CDK9 indicates a poor prognosis in CRC.The incidence of autophagy and the expressions of Beclin 1 and ATP binding cassette transporter G2 are different in left and right colon cancer,and autophagy may be involved in the occurrence of chemotherapy resistance.In this article,the roles of CDK9,ATP binding cassette transporter G2 and Beclin 1 in CRC were elucidated,emphasizing the linkages among them and providing potential therapeutic targets of CRC.
Zhong-Bao ShaoKe HeYu-Bin SuZhi Shi
关键词:CHEMOTHERAPY
新型钉尾横连在后路寰枢椎固定中的生物力学分析被引量:1
2024年
背景:后路寰-枢椎椎弓根钉棒内固定是治疗寰枢椎脱位的主要方法,横连接在内固定系统抗旋转能力中起着重要作用。新型寰椎钉尾横连可以有效克服传统横连安装不便、影响植骨床和脊髓损伤可能等缺点,但不同安装模式的新型钉尾横连的生物力学性能尚不清楚。目的:测试不同安装模式的新型寰椎钉尾横连在后路寰-枢椎椎弓根钉棒内固定系统中的生物力学特性,为临床选择最佳安装模式提供理论依据。方法:6具新鲜人体枕颈标本作为完整组(A组),在完整组基础上建立Ⅱ型齿状突骨折的寰枢椎失稳模型(B组),在失稳组基础上对每具标本先后进行后路寰-枢椎椎弓根钉、棒内固定(C组),在C组上依次安装不同模式新型寰椎钉尾横连,其中包括上水平横连(两寰椎螺钉钉尾)为D组,下水平横连(两枢椎螺钉钉尾)为E组,斜形横连(左上右下为F组,左下右上为G组),交叉横连为H组。在三维运动机上将标本模型按顺序进行前屈、后伸、左右侧屈和左右旋转测试,获取各个内固定状态下的寰枢椎活动度。运用重复测量方差分析评价各组模型的生物力学特性。结果与结论:①在6种工况下,A、C、D、E、F、G、H组寰枢椎活动度小于B组,差异均有显著性意义(P<0.05);②在前屈、后伸状态下,5种横连内固定组相比无统计学差异(P>0.05);③在左右旋转方向上,D、E组与F、G、H组对比差异均有显著性意义(P<0.05),D与E组,F与G组组间对比无统计学差异(P>0.05),F、G与H组对比亦无统计学差异(P>0.05);④提示在前屈、后伸状态下,5种钉尾横连组生物力学稳定性相当;但在左右旋转状态下,斜形钉尾横连和交叉钉尾横连的稳定性明显优于上下钉尾横连组;而斜形钉尾横连具备和交叉横连同等的抗旋转稳定性,故值得临床优先推荐。
欧阳北平马向阳罗春山邹小宝陆廷盛陈啟鸰
关键词:后路寰枢椎内固定生物力学
交联诱导重组装多重刺激响应型聚合物胶束的制备及抗肿瘤应用
2024年
本工作合成了基于聚赖氨酸的三嵌段两亲性聚合物mPEG-P(LL/LL-LA)-PCL-IR820,其中聚赖氨酸链为交联剂硫辛酸(LA)提供了反应位点,疏水链段的聚己内酯(PCL)为物理包埋化疗药物阿霉素(DOX)提供了可行性。随后,光敏剂(IR820)通过酯键接枝到PCL上得到mPEG-P(LL/LL-LA)-PCL-IR820。将聚合物通过溶剂蒸发法制备未交联载药胶束(DUCM),再使用交联诱导剂二硫苏糖醇(DTT)诱导LA制备交联载药胶束(DCM)。由于内部交联结构的存在,DCM在经历注射和血液循环后保持结构稳定,并且在进入肿瘤细胞后,LA中的二硫键会在肿瘤细胞中高浓度谷胱甘肽(GSH)作用下断裂,从而释放化疗药物,避免了未交联胶束因剪切力和蛋白质吸附作用而提前裂解,进而避免了药物在体内的非特异性分布。最终,该交联纳米胶束协同化疗和光动力疗法高效杀死癌细胞,为胶束在药物传递系统中的研发提供了有价值的参考。
唐昭敏赵健清周建仁唐婉兰魏佳元韩秉锟吕文轩
关键词:胶束光疗
新型钉尾横连在后路寰枢椎内固定中的三维有限元分析
2024年
背景:在寰枢关节疾病采用后路寰枢椎椎弓根螺钉内固定术(C_(1)-C_(2)pedicle screw-rod fixation,C_(1)-C_(2)PSR)中加用传统的棒-棒横连可以为螺钉/棒结构提供更坚固抗旋转稳定性,但有安装困难、影响植骨床和脊髓损伤的风险。作者设计的新型寰椎钉尾横连(horizontal screw-screw crosslink,hS-S CL)可以有效克服上述缺点,但其生物力学性能尚不清楚。目的:利用三维有限元分析新型寰椎钉尾横连在C_(1)-C_(2)PSR中的生物力学特性。方法:采集1名成人健康男性志愿者枕骨底到枢椎(C0-2)的CT薄层扫描数据,分别建立寰枢椎有限元模型:正常组、失稳组、失稳+C_(1)-C_(2)PSR(无横连组)、C_(1)-C_(2)PSR+hS-S CL(钉尾横连组)。对各个有限元模型加载1.5 Nm的扭矩,计算出4组模型在屈伸、左右侧屈、左右旋转工况下的活动度及横连应力峰值,并提取内固定应力云图。结果与结论:①失稳组较正常组的运动范围明显增大43.8%-78.7%;2种内固定组在6种工况下的运动范围较失稳组减少90.2%-98.7%,在屈伸状态下的运动范围基本一致,但在侧屈及旋转状态下,钉尾横连组较无横连组运动范围分别减少34.3%-43.8%和78.6%-79.1%,其中在旋转状态运动范围减少最为明显;②2种内固定内植物模型应力峰值:钉尾横连组最大应力总体上小于无横连组,内固定组在后伸时应力峰值最小;③内植物的应力云图:显示内固定未出现明显的应力集中现象,且主要的应力分布区域为螺钉根部与骨质结合部,横连两端与螺钉尾槽或连接棒结合部;④新型钉尾横连能明显提高内固定的抗旋转稳定性,在三维运动上承担部分应力,降低内植物的最大应力;钉尾横连两端的应力分布明显,该部位可能出现横连的断裂。
欧阳北平马向阳罗春山邹小宝陆廷盛陈啟鸰
关键词:后路寰枢椎三维有限元内固定
橡塑鞋微孔材料交联密度特征值试验方法
本文件规定了橡塑鞋微孔材料交联密度特征值的试验方法。 本文件适用于橡塑鞋微孔材料交联密度特征值的测定。
钉尾横连与棒-棒横连在后路寰枢椎固定中的生物力学对比研究
2023年
目的探讨钉尾横连在后路寰-枢椎椎弓根钉棒内固定系统中生物力学稳定性。方法6具新鲜人体枕颈标本分为完整状态组(A组),在完整状态组上建立II型齿状突骨折的寰枢椎失稳模型(B组),在失稳组上对每具标本先后进行后路寰枢椎椎弓根钉棒内固定(C_(1)~C_(2)pedicle screw-rod fixation C_(1)~C_(2)PSR)(C组),在C组基础上分别装置传统棒-棒横连(horizontal rod-rod crosslink,hR-R CL)为D组和钉尾横连(horizontal screw-screw crosslink,hS-S CL)为E组,E组包括上横连(两寰椎螺钉钉尾)E_(1)组和下横连(两枢椎螺钉钉尾)E_(2)组,在三维运动机上将标本模型按顺序进行前屈、后伸、左右侧屈和左右旋转测试,获取每组标本的寰枢椎活动度(ROM)。运用重复测量方差分析评价各组的生物力学特性。结果①在各种状态下,完整组及内固定组活动度小于失稳组,有显著差异(P<0.05);②在前屈、后伸状态下,4种内固定组活动度无统计学差异(P>0.05),活动度(ROM):A组0.05),E_(1)和E_(2)组在各种状态下活动度也无计学差异(P>0.05)。结论横连在后路寰枢椎钉棒内固定中具有良好的抗轴向旋转稳定性;钉尾横连具有与传统棒-棒横连相同的生物力学稳定性;钉尾横连安装在寰椎侧和枢椎侧生物力学性能基本相同。
欧阳北平马向阳罗春山邹小宝梁栋柱陆廷盛陈啟鸰
关键词:后路寰枢椎生物力学

相关作者

李慧
作品数:55被引量:108H指数:5
供职机构:华东理工大学材料科学与工程学院上海市先进聚合物材料重点实验室
研究主题:乳液聚合 丁腈橡胶 超临界CO2 嵌段共聚物 交联
吴驰飞
作品数:250被引量:403H指数:11
供职机构:华东理工大学材料科学与工程学院
研究主题:炭黑 天然橡胶 丁腈橡胶 纳米炭黑 有机小分子
王庆国
作品数:93被引量:204H指数:6
供职机构:青岛科技大学
研究主题:聚酯 可生物降解 有机盐 辐射交联 辐射硫化
赵辉
作品数:272被引量:983H指数:17
供职机构:长江大学
研究主题:油藏 数值模拟 井间连通性 湿气 连通性
沈飞
作品数:14被引量:28H指数:3
供职机构:华东理工大学材料科学与工程学院高分子合金研究室
研究主题:丁腈橡胶 配位交联 NBR/PVC 交联 配位反应