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The Relationship between Pendant Phosphate Groups and Mechanical Properties of Polyisoprene Rubber

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Chinese Journal of Polymer Science 2021年第4期39卷 465-473,I0006页

作者： Shi-Qi Li Mao-Zhu Tang Cheng Huang Rong Zhang Guang-Su Huang yun-xiang xu College of Polymer Science&Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

It is still a great challenge to mimic the structure and function of natural rubber by introducing polar components into synthetic *** order to explore the function of phosphate groups on the mechanical properties of polyisoprene rubber,a terminally functionalized compound(PIP-P)containing phosphate groups was synthesized and further vulcanized to prepare the model compound *** analyzing the test results,it was found that these phosphate groups formed polar aggregates in non-polar polyisoprene rubber matrix,serving as an additional dynamic cross-linking sites,which increases the cross-linking density and improves mechanical *** influence of the phosphate groups on the strain-induced crystallization(SIC)was further investigated via synchrotron wide-angle X-ray diffraction(WAXD)*** phosphate group aggregates not only reduced the onset strain of SIC,but also slowed down the molecular chain mobility,which hinder the crystal lateral *** above results help us to gain a deeper understanding for the function of phosphate groups in the formation of"naturally occurring network"and guide the molecular design of next generation polyisoprene rubber.

关键词： Phosphate groups Strain-induced crystallization Naturally occurring network Natural rubber

Promoted Comprehensive Properties of Polyisoprene Rubber with Extremely High Fatigue Resistance Enabled by Oligopeptide Aggregates

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Chinese Journal of Polymer Science 2023年第8期41卷 1250-1260,I0008页

作者： Yu He Ran xu Rong Zhang Chang-Cheng Wang Shi-Qi Li Jian Cao Mao-Zhu Tang yun-xiang xu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

For decades,the preparation of polyisoprene rubber that can match the comprehensive properties of natural rubber(NR)has been *** sacrificial bonds have been used to promote the strength and toughness of rubbers,little is known about their effects on fatigue resistance,which is important in dynamic ***,terminal block and randomly functionalized polyisoprene rubbers tethered with di-alanine,tri-alanine and tetra-alanine were *** results showed that the flow activation energy,aggregates ordering and energy dissipation of the hydrogen-bonded aggregates increase with the elongation of oligopeptide length(XA,X=2,3,4),therefore resulting in enhanced mechanical strength and toughness of corresponding ***,the tear strengths are barely affected by oligopeptide lengths in block samples,but promoted from dipeptide to tetrapeptide in random samples,probably due to the well dispersed oligopeptide *** importantly,it is found that the tight binding aggregates of oligopeptides are critical for the excellent fatigue resistance,which is absent in polyisoprene and natural *** loose aggregates dissociate and recombine repeatedly under cyclic loading and the tight aggregates keep the network integrated and ***,the largest hysteresis of PIP-4A-V with the longest oligopeptide length give the lowest heat generation,which is contrary to the traditional sacrificial ***,the oligopeptide aggregates have repeatable energy dissipation properties and cycle life comparable to or even surpassing those of the linked proteins in NR,resulting in similar tensile strength,fracture toughness,and better fatigue resistance relative to *** deep insight on the role of oligopeptide aggregates is very useful for the engineering rubbers served in dynamic environments.

关键词： Polyisoprene Hydrogen bonding Oligopeptides Fatigueresistance

Unsymmetric Side Chains of Indacenodithiophene Copolymers Lead to Improved Packing and Device Performance

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Chinese Journal of Polymer Science 2020年第4期38卷 342-348,I0005页

作者： Ying Yang Tong Shan Jian Cao Hua-Chun Wang Ji-Kang Wang Hong-Liang Zhong yun-xiang xu College of Polymer Science&Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai200240China

Two conjugated polymers(PulDTBD and PulDTQ)with un symmetric side chai ns have been prepared for polymer solar cells using two other polymers(PIDTBD and PIDTQ)with symmetric side chains as control *** combi nation of methyl a nd 4-hexylphenyl side chai ns on the same bridged carb on can en sure good solubility,decrease tt-tt stacking dista nces,and bring proper miscibility with PC71BM ***,the corresp on ding polymer solar cells(PSCs)based on donor polymers with un symmetric side chains exhibited enhanced short-circuit current density(■)and power conversion efficiency(PCE)compared with those of control *** PIDTBD and PIDTQ based devices possessed low PCE of 2.13%and 1.48%,while PCEs of devices based on PulDTBD and PulDTQ were improved to 3.93%and 4.12%,*** results demonstrate that unsymmetric side chain engineering of conjugated polymers is an effective approach to achieve high performance PSCs.

关键词： Polymer solar cell Indacenodithiophene Side-chain engineering Unsymmetric

Surfactant Mediated Microphase Separation in Miscible Block Copolymer of Poly(4-vinyl pyridine-b-hydroxybutylacrylate)

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Chinese Journal of Polymer Science 2023年第6期41卷 897-904,I0007页

作者： xiang-yun xu Yu-Tong Gao Ying-Ying Wang You-Shuang Zhou Bi-Jin Xiong Jin-Tao Zhu Key Laboratory of Materials Chemistry for Energy Conversion and Storage(HUST)of Ministry of Education School of Chemistry and Chemical Engineering.Huazhong University of Science and Technology(HUST)Wuhan 430074China Key Laboratory of Optoelectronic Chemical Materials and Devices(Ministry of Education) Jianghan UniversityWuhan 430056China Key Laboratory of Green Preparation and Application of Functional Materials(Ministry of Education) Hubei Key Laboratory of Polymer MaterialsFaculty of Materials Science and EngineeringHubei UniversityWuhan 430062China

Miscible disordered block copolymers(BCPs)are rarely studied due to the limits in self-assembly into ordered ***,we proposed a facile method for the transformation of disordered miscible BCPs to comb-like BCPs with well-ordered microphase separation structures via blending with amphiphilic *** this work,poly(4-vinyl pyridine-b-hydroxybutylacrylate)(P4VP-b-P4HBA)was applied as a model of miscible disordered BCPs and the microphase separation was induced via blending with surfactants of dodecylbenzene sulfonic acid(DBSA)and 3-pentadecylphenol(PDP).The ordered microstructures including spherical and cylindrical morphologies were confirmed by transmission electron microscopy(TEM)and small angle X-ray scattering(SAXS)*** ordered microstructures thermal sensitive,in which ordered and disordered transformation(ODT)was observed in the blend of P4VP-b-P4HBA and PDP whereas it disappeared in the blend of P4VP-b-P4HBA and *** results show that the thermal stability of the ordered microstructures are strongly depends on the interactions between the miscible BCPs and surfactants,which investigated by in situ SAXS and Fourier transform infrared spectrometer(FTIR).The combination of miscible BCPs and surfactant creates a feasible strategy to fabricate ordered nanostructures,which could be employed to develop complicated nanomaterials.

关键词： ordered disordered vinyl

Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials

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Neural Regeneration Research 2025年第9期20卷 2437-2453页

作者： Siyi xu Junqiu Jia Rui Mao xiang Cao yun xu Department of Neurology Nanjing Drum Tower HospitalClinical College of Jiangsu UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Science&Peking Union Medical CollegeNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases Nanjing UniversityNanjingJiangsu ProvinceChina Jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjingJiangsu ProvinceChina Nanjing Neurology Medical Center NanjingJiangsu ProvinceChina

Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health *** optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent *** are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,which induce cell ***,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these *** evidence has highlighted the significant role of mitophagy in acute central nervous system *** this review,we provide a comprehensive overview of the process,classification,and related mechanisms of *** also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate *** the final section of this review,we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

关键词： autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control mitophagy spinal cord injury subarachnoid hemorrhage traumatic brain injury

Narrow-band imaging in the diagnosis of early esophageal cancer and precancerous lesions

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Chinese Medical Journal 2009年第7期122卷 776-780页

作者： HUANG Liu-ye CUI Jun WU Cheng-rong LIU yun-xiang xu Ning Department of Gastroenterology Yantai Yuhuangding HospitalAffiliated to Medical College of Qingdao University YantaiShandong 264000 China

Background In the recent years, the incidence of esophageal cancer in China has increased. The key point for raising the survival rate is the diagnosis and treatment at an early stage. Narrow-band imaging （NBI） can enhance the contrast of the mucous membrane of the esophagus without staining. This study aimed to explore the value of NBI in the diagnosis of early esophageal cancer and precancerous lesions. Methods The esophagus was examined with ordinary endoscopy and NBI endoscopy. Pit patterns and blood capillary forms were examined with routine magnifying endoscopy and NBI endoscopy. Finally, a 1.2% Lugoul＇s iodine solution was used to stain the esophageal mucosal surface and a biopsy was taken at all the sites where NBI or iodine staining was positive. NBI and iodine staining scales were compared with pathologic diagnosis, which was considered as the gold standard. Results A total of 90 cases （138 lesions in total） were diagnosed as early esophageal cancer or precancerous lesions; 104 lesions （75.4%） were detected with ordinary endoscopy, 120 lesions （87.0%） were detected with NBI endoscopy, and 138 lesions （100%） were detected with iodine staining. The lesion detection rate of NBI was significantly lower than that of iodine staining （X2=17.176, P 〈0.01）. However, there was no significant difference between NBI and iodine staining for the diagnosis of high grade intraepithelial neoplasia （X2=1.362, P 〉0.05）, while the detection rate of NBI was significantly lower than that of iodine staining for the diagnosis of low grade intraepithelial neoplasia （X2=13.388, P 〈0.01）. The pit pattern and blood capillary form of early esophageal cancer and precancerous lesions could be demonstrated clearer with NBI than with ordinary endoscopy. Conclusions NBI can enhance the contrast of the mucous membrane of the esophagus without staining. The combination of NBI and iodine staining can raise the diagnostic rate of early esophageal cancer and precancerous lesions.

关键词： esophageal neoplasms endoscopy narrow-band imaging

Bis(thien-2-yl)-2,1,3-benzothiadiazole-Diketopyrrolopyrrole Based Acceptor-Acceptor Conjugated Polymers: Design,Synthesis and the Synergistic Effect of the Substituent on Their Solar Cell Properties

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Bis(thien-2-yl)-2,1,3-benzothiadiazole-Diketopyrrolopyrrole ...

河南省化学会2018年学术年会

作者： Jun-ping Du Peng-ju Qin Lian-cai xu Shao-ming Fang Feng-hua Chen yun-xiang xu Jiang Huang College of Material and Chemical Engineering Zhengzhou University of Light Industry

Three acceptor-acceptor conjugated copolymers(TBT-DPP, FTBT-DPP and HFTBT-DPP) based on diketopyrrolopyrrole unit and bis(thien-2-yl)-2,1,3-benthothiadiazole unit with different substituent groups as side chains have been synthesized and fully characterized. Polymer solar cells based on these copolymers as the electron donors and PC71 BM as the acceptor were fabricated. Because of the introduction of the substituent groups to bis(thien-2-yl)-2,1,3-benthothiadiazole fragment, the solubility can be improved effectively while the excellent thermal stability properties of the polymers were retained. Interesting, the photophysical properties, electrochemical properties, film structures and surface morphology of the polymers changed regularity along with the substituent groups. Density function theory calculations about the polymers structure explained the reasons for the change well. Conjugation level of the polymer backbone is one of key factors to effect on their properties. Their polymer solar cells performance is consistent well with their properties. The introduction of the two fluorine atoms induced the power conversion efficiency of the polymer solar cells improved twice while the synergistic effect of the substituent decreased seriously to zero.

关键词： Polymer solar cells Acceptor-acceptor conjugated polymer Synergistic effect Bezothiadiazole Diketopyrrolopyrrole

来源： cnki会议评论

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cnki会议

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陕西山阳盆地晚白垩世介形类

微体古生物学报 1991年第2期8卷 227-235,254页

作者：张云翔薛祥煦李存购西北大学地质系西安710069

本文报道了陕西山阳盆地晚白垩世介形类8属16种(包括4个新种及3个未定种),建立了Cypridea-Talicypridea-Eucypris组合。该组合与国内外晚白垩世晚期非海相介形类组合相似。共生的化石有恐龙、恐龙蛋及腹足类等。这是晚白垩世介形类在秦... 详细信息

本文报道了陕西山阳盆地晚白垩世介形类8属16种(包括4个新种及3个未定种),建立了Cypridea-Talicypridea-Eucypris组合。该组合与国内外晚白垩世晚期非海相介形类组合相似。共生的化石有恐龙、恐龙蛋及腹足类等。这是晚白垩世介形类在秦岭地区的首次发现,它对秦岭地区中、新生代红色盆地地层的划分与对比具有重要意义。

关键词：介形类白垩纪陕西山阳盆地

Mainchain conformation ordering self-assembly tailored room temperature phosphorescence emission

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Science China Chemistry 2025年第01期 329-336页

作者： Yuzhu Li Yumeng Gao Feng Tian Yu Wang Yuan Yao Shaoliang Lin xiang Ma Binbin xu Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Key Laboratory for Advance Materials and Feringa Noble Prize Scientist Joint Research Centre Frontiers Science for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular Engineering East China University of Science & Technology

Developing organic room-temperature phosphorescence （RTP） materials with a wide range of tunable-emission is significant in expanding the applications of RTP ***,we rationally designed amphiphilic alternating copolymers poly(1,2-bis（4-alkoxyphenyl）ethane-1,2-dione-alt-（ethylene glycol）x)(P（Bz-alt-EGx）) that combined the advantage of alternating benzil and EGxskeleton,and tunable mainchain *** a mainchain conformation ordering assembly （COA） process,P（Bz-alt-EGx） self-assembled into well-defined platelets,and such assemblies emitted blue RTP at ca.425 nm due to the ordered folded-chain conformation and confined *** contrast,traditional self-assembly （TA） of P（Bz-alt-EGx） obtained less ordered aggregates,such as asymmetric worms,vesicles,and rod-like *** resultant less ordered aggregates exhibited yellow-green RTP at ca.550 *** wide-tuning RTP emission in solution （between blue and yellow-green,over125 nm） is realized using the P（Bz-alt-EGx） alternating copolymers under the treatment of different self-assembly *** study uncovers a new strategy to tailor the RTP emission through different self-assembly pathways and holds great promise for the fabrication of advanced optical materials.

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