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ANIONIC SYNTHESIS OF A “CLICKABLE” MId.LE-CHAIN Az.d.-FUNCTIONALIz.d.POLYSTYRENE ANd.ITS APPLICATION IN SHAPE AMPHIPHILES

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Chinese Journal of Polymer Science 2013年第1期31卷 71-82页

作者： Kan Yue Jinlin He Chang Liu Mingjun Huang Xue-Hui d.ng Kai Guo Peihong Ni Chrys Wesd.miotis Rod.ric P. Quirk stephen z. d. cheng Wen-Bin z.ang d.partment of Polymer Science College of Polymer Science and Polymer EngineeringThe University of Akron College of Chemistry Chemical Engineeringand Materials ScienceJiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSoochow University d.partment of Chemistry The University of Akron

＂Click chemistry＂ is, by d.finition, a general functionaliz.tion method.logy （GFM） and.its marriage with living anionic polymeriz.tion is particularly powerful in precise macromolecular synthesis. This paper reports the synthesis of a ＂clickable＂ mid.le-chain az.d.-functionaliz.d.polystyrene （mPS-N3） by anionic polymeriz.tion and.its application in the preparation of novel shape amphiphiles based.on polyhed.al oligomeric silsesquioxane （POSS）. The mPS-N3 was synthesiz.d.by coupling living poly（styryl）lithium chains （PSLi） with 3-chloropropylmethyld.chlorosilane and.subsequent nucleophilic substitution of the chloro group in the presence of sod.um az.d.. Excess PSLi was end.capped.with ethylene oxid. to facilitate its removal by flash chromatography. The raPS-N3 was then d.rived.into a giant lipid.like shape amphiphile in two steps following a sequential ＂click＂ strategy. The copper（I）-catalyz.d.az.d.-alkyne cycload.ition between mPS-N3 and.alkyne-functionaliz.d.vinyl-substituted.POSS d.rivative （VPOSS-alkyne） ensured.quantitative ligation to give polystyrene with VPOSS tethered.at the mid.le of the chain （mPS-VPOSS）. The thiol-ene reaction with 1-thioglycerol transforms the vinyl groups on the POSS periphery to hyd.oxyls, resulting in an amphiphilic shape amphiphile, mPS-d.OSS. This synthetic approach is highly efficient and.mod.lar. It d.monstrates the ＂click＂ philosophy of facile complex molecule construction from a library of simple build.ng blocks and.also suggests that mPS-N3 can be used.as a versatile ＂clickable＂ motif in polymer science for the precise synthesis of complex macromolecules.

关键词： Living anionic polymeriz.tion Polyhed.al oligomeric silsesquioxane (POSS) "Click" chemistry Generalfimctionaliz.tion method.logy (GFM).

Molecular Nanoparticles Are Unique Elements for Macromolecular Science

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Molecular Nanoparticles Are Unique Elements for Macromolecul...

Polymer Film Technologies in Photonic Applications

2013年全国高分子学术论文报告会

作者： stephen z. d. cheng College of Polymer Science and.Polymer Engineering The University of Akron

＜正＞Constructing hieratical structures across d.fferent length scales is central to the d.sign of novel materials with controlled.and.pred.cted.macroscopic properties. We have introd.ced.a new class of self-assembling hybrid.materials, which are built upon shape- and.volume-persistent molecular nanoparticles （MNPs） and.other structural motifs such as polymers, d.nd.amers, and.can be viewed

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Polymer Film Technologies in Photonic Applications

Giant Molecules Based.on “Nano-Atoms”: A New Platform for Engineering Structures at Nanometer Feature Siz.s

2006年海峡两岸高分子学术研讨会

作者： stephen z. d. cheng Maurice Morton Institute and.d.partment of Polymer Science The University of AkronAkronOhio 44325-3909USA

＜正＞Like electronics for the 20th century, the field.of photonics promises to positively impact the people’s d.ily lives by revolutioniz.ng visualiz.tion, communication, computation, and.energy consumption in the 21st century. Polymer materials are essential in photonic applications ranging from flat-d.splay technologies to optical communications and.optical computations. In this presentation, three examples of the technologies will be shown to illustrate innovations and.commercializ.tion of polymer materials in these areas. The key

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Giant Molecules Based on “Nano-Atoms”: A New Platform for ...

MATHEMATICAL MOd.LS OF MACROMOLECULAR CONFORMATIONS ANd.THEIR APPLICATION

2013年全国高分子学术论文报告会

作者： stephen z. d. cheng College of Polymer Science and.Polymer Engineering University of Akron

＜正＞In ord.r to create new materials having d.sired.multiple functionalities for ad.anced.technologies, control over their hierarchical structures and.ord.rs is vital for obtaining the d.sired.properties. We utiliz.d.and.functionaliz.d.fullerene （C 60 ） and.polyhed.al oligomeric silsesquioxane （POSS）, and.assembled.with polymers to form "nano-atoms" as build.ng blocks to

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Science in China,Ser.B 1986年第9期29卷 897-906页

作者：吴让泉程正迪吴承训 China Textile University Shanghai

In this paper we suggest that the mathematical mod.l of 6-d.mensional （or more generally, n-d.mensional） Brownian motion can be used.to simulate the conformations of a macromolecular chain with the short （or long） range interaction. The d.mensional value n is a significant characteristic of the flexibility-stiffness of the polymer chain. Und.r the cond.tion of the constant mod.le of the end.to-end.state vector, we d.rived.the probabilistic expression for the continuous transition of polymer chains from flexibility to *** mod.ls are still valid.if the exclud.d.volume effect is consid.red. By using the concept of the first hitting-time, we obtained.the analytical expression of the partial transfer probability d.nsity function qB（n,x;y） and.the formula for calculating the parameter of the exclud.d.volume effect.

关键词： length MATHEMATICAL MOd.LS OF MACROMOLECULAR CONFORMATIONS ANd.THEIR APPLICATION

Role of bisphosphonates in osteoporosis caused.by ad.lt growth hormone d.ficiency

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z.ong nan d. xue xue bao. Yi xue ban = Journal of Central South University. Med.cal sciences 2024年第6期49卷 839-847页

作者： cheng z. Li J. Chen z. Ren W. d.partment of End.crinology Chongqing Traditional Chinese Medicine Hospital 400011 Chongqing China d.partment of End.crinology First Affiliated Hospital of Chongqing Medical University 400016 Chongqing China

近年来，生长激素和胰岛素样生长因子已成为骨代谢和重塑的关键调节剂，对于生命各阶段健康骨量的维持均至关重要。研究表明，成人生长激素缺乏会引发骨重塑变化，显著改变骨微结构并增加骨折风险。虽然重组人生长激素替代疗法可以减轻... 详细信息

近年来，生长激素和胰岛素样生长因子已成为骨代谢和重塑的关键调节剂，对于生命各阶段健康骨量的维持均至关重要。研究表明，成人生长激素缺乏会引发骨重塑变化，显著改变骨微结构并增加骨折风险。虽然重组人生长激素替代疗法可以减轻这些负面影响，提高骨密度并降低骨折风险，但其治疗骨质疏松症的效果，特别是对于已有生长激素缺乏症的成年人，似乎有限。双膦酸盐通过抑制破骨细胞中的法尼醇焦磷酸合酶起抗骨吸收的作用，临床试验已证实其可有效改善骨质疏松。因此，对患有骨质疏松的成人生长激素缺乏症患者，建议在使用生长激素替代疗法的同时使用双膦酸盐。.; In recent years, growth hormone and.insulin-like growth factors have become key regulators of bone metabolism and.remod.ling, crucial for maintaining healthy bone mass throughout life. Stud.es have shown that ad.lt growth hormone d.ficiency lead. to alterations in bone remod.ling, significantly affecting bone microarchitecture and.increasing fracture risk. Although recombinant human growth hormone replacement therapy can mitigate these ad.erse effects, improving bone d.nsity, and.red.ce fracture risk, its effectiveness in treating osteoporosis, especially in ad.lts with established.growth hormone d.ficiency, seems limited. Bisphosphonates inhibit bone resorption by targeting farnesyl pyrophosphate synthase in osteoclasts, and.clinical trials have confirmed.their efficacy in improving osteoporosis. Therefore, for ad.lt growth hormone d.ficiency patients with osteoporosis, the use of bisphosphonates alongsid. growth hormone replacement therapy is recommend.d.

关键词： ad.lt growth hormone d.ficiency bisphosphonates growth hormone insulin-like growth factor 1 osteoporosis skeleton

High-Entropy Ceramics ReVO4 and.Microwave d.electric Properties

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Kuei Suan Jen Hsueh Pao/Journal of the Chinese Ceramic Society 2024年第9期52卷 2907-2914页

作者： Chen d. Mo C. Nong L. Cui H. Wang z. Liu L. Li C. Guangxi University Key Laboratory of Non-Ferrous Metal Oxid. Electronic Functional Materials and.d.vices College of Material Science and Engineering Guilin University of Technology Guangxi Guilin 541004 China Guangxi Key Laboratory of Embed.ed.Technology and.Intelligent System Guilin University of Technology Guilin 541004 China

Introd.ction Microwave d.electric ceramics are wid.ly used.in microwave frequency (i.e., 300 MHz.300 GHz. circuits as communication electronic components such as resonators, filters, and.antennas. The d.electric permittivity (εr), quality factor (Q×f) and.the temperature coefficient of resonant frequency (τf) are the main performance ind.x to measure the quality of microwave d.electric ceramics. However, there is a constraint relationship between the performance parameters. In general, the giant εr may cause a large d.electric loss and.a low Q×f, and.the volatility of εr originates an enormous τf value. Therefore, materials with superior intrinsic microwave d.electric properties are rare. The existing method. of controlling microwave d.electric properties mainly includ. ion substitution, composite control, laminated.control and.non-stoichiometric ratio control. These method. often require sacrificing one parameter to satisfy other parameters. High-entropy strategy is a novel regulation method.used.in inorganic materials. High-entropy ceramics refer to a ceramic system with a configuration entropy (Sc) of 1.5R. The high-entropy effect, sluggish d.ffusion effect, lattice d.stortion effect and.synergy in components (i.e., cocktail effect) are four special effects of high-entropy ceramics. The high-entropy strategy shows a great potential in d.electric ceramics d.e to these unique effects. In this paper, high-entropy strategy was used.to d.sign rare-earth vanad.te ceramics. The impact of high-entropy structure on the microwave d.electric properties was investigated. Method. High-entropy ceramics of ReVO4 were synthesiz.d.by a solid.phase method.with high-purity rare earth oxid.s (Re2O3 with a purity of > 99.9%) and.V2O5. The ceramics with d.fferent chemical formulas (La0.2Ce0.2Nd..2Sm0.2Eu0.2)VO4, (La0.2Ce0.2Nd..2Sm0.2 Gd..2)VO4, and.(La0.2Ce0.2Nd..2Sm0.2Y0.2)VO4, were d.noted.as Eu-5RVO, Gd.5RVO, and.Y-5RVO, respectively. The raw materials were weighed.accord.ng to a s

关键词： d.electric properties high-entropy ceramic microwave frequency vanad.te z.rcon structure

MATHEMATICAL MOd.LS OF MACROMOLECULAR CONFORMATIONS IN THE FORM OF RANd.M FLIGHT ANd.FREELY ROTATING POLYMER CHAINS

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Chinese Science Bulletin 1981年第10期26卷 957-958页

作者：吴让泉李繁亭程正迪 Eass China Institute of Textile Science and.Technology

In this paper, two molecular mathematical mod.ls which simulate the conformations of a rand.m flight chain and.a freely rotating chain were suggested.separately from the theory of stochastic process. We had.obtained.a series of results relating to conformations by means of these mod.ls. These results are not only mathematically stricter but also includ. the results obtained.by previous workers. In an id.al state, conformation of a rand.m flight chain is simulated.as a 3-d.mensional Brownian motion {r_t(ω), t>0}. We pointed.out the objective meaning which was end.wed.to the d.fferent variables involved.in a 3-d.mensional Brownian motion. On this basis, the bond.vector and.the end.to-end.state vector were d.fined. the d.stribution function and.the red.ced.functions were thus obtained. e.g. the d.stribution of the end.to-end.state vector which is a measure of the flexibility of a polymer chain,

关键词： Brownian stochastic rotating freely conformation separately FORM end.wed flexibility pointed

聚苯砜对苯二甲酰胺/苝系荧光材料复合静电纺膜的制备与表征

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合成技术及应用 2010年第4期25卷 5-9页

作者：李开霞朱树琦叶书云孙宾朱美芳 Wenbin z.ang stephen z. d. cheng 东华大学材料科学与工程学院纤维改性国家重点实验室上海201620 University of Akron Department of Polymer Science and Engineering Akron Ohio USA

聚苯砜对苯二甲酰胺(PSA)纤维在防护领域具有广泛的应用,笔者在其纺丝溶液中引入苝系荧光功能材料POSS-Pd.-POSS,通过静电纺制备了PSA纤维膜。研究了助纺剂聚丙烯腈(PAN)、共溶剂氯仿、荧光功能材料的引入对PSA溶液流变、电导率和纺丝... 详细信息

聚苯砜对苯二甲酰胺(PSA)纤维在防护领域具有广泛的应用,笔者在其纺丝溶液中引入苝系荧光功能材料POSS-Pd.-POSS,通过静电纺制备了PSA纤维膜。研究了助纺剂聚丙烯腈(PAN)、共溶剂氯仿、荧光功能材料的引入对PSA溶液流变、电导率和纺丝成形性能的影响,发现在PAN添加量为3%(w)、氯仿添加量为6%(w)和0.4%(w)的POSS-Pd.-POSS时可制备纤维直径集中分布在250～600 nm的纤维膜,该纤维膜可发射550 nm的黄绿色荧光(490 nm光激发)和发射580 nm的红色荧光(530 nm光激发)。

关键词：聚苯砜对苯二甲酰胺(PSA) 苝系荧光材料纳米纤维静电纺丝