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AMPHIPHIliC STAR-BLOCK COPOLYMERS BY IODIDE-MEDIATED RADICAL POLYMERIZATION

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Chinese Journal of Polymer Science 2007年第6期25卷 609-619页

作者： bing-yi li yan Shi Zhi-feng Fu Wan-tai yang Shu-ke Jiao State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Amphiphilic star-block copolymers composed of polystyrene and poly（acrylic acid） were synthesized by iodide- mediated radical polymerization. Firstly, free radical polymerization of styrene was carried out with AIBN as initiator and 1,1,1-trimethyolpropane tri（2-iodoisobutyrate） as chain transfer agent, giving iodine atom ended star-shaped polystyrene with three arm chains, R（polystyrene）3. Secondly, tert-butyl acrylate was polymerization using polystyrene obtained as macro-chain transfer agent, and star-block copolymer, R（polystyrene-b-poly（tert-butyl acrylate））3 with controlled molecular weight was obtained. Finally, amphiphilic star-block copolymer, R（polystyrene-b-poly（acrylic acid））3 was obtained by hydrolysis of R（polystyrene-b-poly（tert-butyl acrylate））3 under acidic condition.

关键词： living radical polymerization Iodide-Mediated radical polymerization Star-block copolymers Amphiphilic copolymers.

FeBr_3-catalyzed dibromination of alkenes and alkynes

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Chinese Chemical Letters 2011年第10期22卷 1195-1198页

作者： Yun Fa Zheng Jian Yu Guo bing yan Xu li Song Luo Department of Chemistry Lishui University Lishui 323000 China

The dibromination of alkenes and alkynes with bromosuccinimide and sodium bromide catalyzed by FeBr_3 under mild conditions has been *** trans-dibromo compounds were exclusively obtained with excellent yields.

关键词： Dibromination Alkenes and alkynes Iron catalyst

Role of interferons in diabetic retinopathy

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World Journal of Diabetes 2021年第7期12卷 939-953页

作者： bing-yan li Wei Tan Jing-ling Zou yan He Shigeo Yoshida bing Jiang Ye-Di Zhou Department of Ophthalmology The Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina Hunan Clinical Research Center of Ophthalmic Disease The Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina Department of Ophthalmology Kurume University School of MedicineKurume 830-0011FukuokaJapan

Diabetic retinopathy(DR)is one of the major causes of visual impairment and irreversible blindness in developed *** from abnormal angiogenesis,inflammation is the most specific and might be the initiating factor of *** a key participant in inflammation,interferon-gamma(IFN-γ)can be detected in different parts of the eye and is responsible for the breakdown of the blood-retina barrier and activation of inflammatory cells and other cytokines,which accelerate neovascularization and neuroglial *** addition,IFN-γis involved in other vascular complications of diabetes mellitus and angiogenesis-dependent diseases,such as diabetic nephropathy,cerebral microbleeds,and age-related macular *** treatments,such as anti-vascular endothelial growth factor agents,vitrectomy,and laser photocoagulation therapy,are more effective for angiogenesis and not tolerable for every *** ongoing clinical trials are exploring effective drugs that target *** instance,IFN-αacts against viruses and angiogenesis and is commonly used to treat malignant ***,IFN-αhas been shown to contribute to alleviating the progression of DR and other ocular *** this review,we emphasize the roles that IFNs play in the pathogenesis of DR and discuss potential clinical applications of IFNs in DR,such as diagnosis,prognosis,and therapeutic treatment.

关键词： Interferons Cytokines Diabetic retinopathy Interferon-alpha Interferongamma Inflammation

Role of flood discharge in shaping stream geometry:Analysis of a small modern stream in the Uinta Basin,USA

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Journal of Palaeogeography 2017年第1期6卷 84-95页

作者： Guang-Ming Hu Ru-Xin Ding yan-bing li Jing-Fu Shan Xiao-Tao Yu Wei Feng School of Geosciences Yangtze UniversityWuhan 430100HubeiChina State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China School of Earth Science and Geological Engineering Sun Yat-sen UniversityGuangzhou 510275GuangdongChina Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes Guangzhou 510275GuangdongChina The Third Production Plant Daqing Oilfield BranchPetroChinaDaqing 163000HeilongjiangChina

This small modern river system is located on a retativety flat （about 1°-2°）, unconsotidated sandy pediment surface in the Uinta Basin of Utah, USA, and it is with a scare of about 30 m tong and 0.4-0.8 m wide, simitar as a natural flume experiment modet. The smart stream is informatty divided into upstream, midstream and downstream. The anatysis shows that flood discharge influences channet sinuosity and morphology to produce an initiat meandering pattern which is tater changed to a braided and then a straisht pattern in the downflow direction. The upstream segment has a hish sinuous geometry dominated by both erosion （cutbanks） and deposition （point bars）. In the resistance of sporadic vegetation rooting in banks, the upstream flood deviates its original direction, which resutts in the powerful flood intensively eroding the cutbank and accreting clastics to build point bars, and thus producing a high sinuous channet. The midstream is dominated by deposits （many smart bars） with a moderate to tow sinuosity. Due to the bad drainage of the high sinuous channel in the upstream, the strong flood can cut off the point bar comptetely or even surmount the tevee in the fast meandering upstream, which widens the channel suddenty with a quick decreasing current power. Then, the ctastics from the upstream are untoaded in the midstream and form many smart bars. Untoaded sediments protect the bank, and the tow-power current brings a moderate erosion to the bank, which forms a moderate to tow sinuous channel in the midstream. The downstream shows multistage erosionat terraces in its retativety straight channets. After the midstream water drops its toad, it becomes ＂dear＂ and reaches downstream, the tower current power is hetptess to reform channet 8eometry. Thus, the downstream channel sesment keeps a tower sinuous geometry, evenstraight partially. Small amounts of fine clastics are deposited, and simultaneously multistage terraces are formed due to regressive flood erosion.

关键词： Sinuosity Braiding Point bar Channel bar Flood discharge Uinta Basin

Treatment Efficiencies of Constructed Wetlands for Eutrophic Landscape River Water

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Pedosphere 2007年第4期17卷 522-528页

作者： HE Sheng-bing yan li KONG Hai-Nan liU Zhi-Ming WU De-Yi HU Zhan-Bo School of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 （China）.

The efficiencies of two types of constructed wetlands for the treatment of low-concentration polluted eutrophic land- scape river water were studied in the western section of the Qingyuan River at the Minhang campus of Shanghai Jiaotong *** first wetland was a single-stage system using gravel as a filtration medium,and the second was a three- stage system filled with combinations of gravel,zeolite,and fly *** from parallel operations of the wetlands showed that the three-stage constructed wetland could remove organics,nitrogen, and phosphorus *** the same time,it could also decrease ammoniacal odour in the *** to the single-stage constructed wetland,it had better nutrient removal efficiencies with a higher removal of 19.37%-65.27% for total phosphorus (TP) and 21.56%- 62.94% for total nitrogen (TN),respectively,during the operation period of 14 *** terms of removal of chemical oxygen demand (COD), turbidity,and blue-green algae,these two wetland systems had equivalent *** was also found that in the western section of the test river,in which the two constructed wetlands were located, the water quality was much better than that in the eastern and middle sections without constructed wetland because COD,TN, and TP were all in a relatively lower level and the eutrophication could be prevented completely in the western section.

关键词： constructed wetland eutrophic landscape river water treatment

常压下环己烷-环氧环己烷二元体系汽液平衡研究

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高校化学工程学报 2012年第4期26卷 547-551页

作者：王训遒闫炳利付丽王卉郑州大学化工与能源学院河南郑州450001

合成环氧环己烷的反应液中常含有环己烷,为获得高纯度的环氧环己烷产品,可采用精馏方法进行分离。而精馏设计计算需要环氧环己烷-环己烷二元体系汽液平衡数据,为此用改进的Rose汽液平衡釜在常压(101.3 kPa)下测定该二元体系的汽液平衡数... 详细信息

合成环氧环己烷的反应液中常含有环己烷,为获得高纯度的环氧环己烷产品,可采用精馏方法进行分离。而精馏设计计算需要环氧环己烷-环己烷二元体系汽液平衡数据,为此用改进的Rose汽液平衡釜在常压(101.3 kPa)下测定该二元体系的汽液平衡数据,并对所测得的数据进行热力学一致性检验,结果表明实验数据符合热力学一致性。以汽相组成的误差平方和作为目标函数,分别用Wilson方程和NRTL方程关联实验数据,得到分子交互作用能量参数,并对汽液平衡计算值与实验值进行比较,发现二者偏差较小,可以满足工程上分离设计的需要。

关键词：汽液平衡环己烷环氧环己烷 Wilson方程 NRTL方程

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肠黏液屏障在肠道中的作用

世界华人消化杂志 2017年第19期25卷 1764-1771页

作者：李冰于岩波山东大学齐鲁医院消化内科山东省济南市250012

肠黏液屏障是覆盖在肠上皮表面的由黏蛋白构成的凝胶型网状结构.MUC2是黏蛋白的主要成分,其特殊结构能保障黏液屏障的结构稳定性和抗性.杯状细胞能通过基础及调节分泌途径生成黏蛋白来维持和更新肠黏液层,肠道菌群也是黏液的组成、厚度... 详细信息

肠黏液屏障是覆盖在肠上皮表面的由黏蛋白构成的凝胶型网状结构.MUC2是黏蛋白的主要成分,其特殊结构能保障黏液屏障的结构稳定性和抗性.杯状细胞能通过基础及调节分泌途径生成黏蛋白来维持和更新肠黏液层,肠道菌群也是黏液的组成、厚度及黏液屏障通透性功能形成的关键因素.肠黏液屏障能防止腔内细菌接触上皮,发挥抗感染作用,调节肠道免疫与外来刺激之间的平衡.而黏液屏障的结构和功能受损在感染性疾病、炎症性肠病、囊性纤维化、肿瘤等多种肠道疾病的发生发展中也起重要作用,或许会成为疾病治疗的新靶点.

关键词：肠黏液屏障黏蛋白杯状细胞肠道菌群

具有QoS特征宽带IP网络队列调度算法的研究

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计算机科学 2003年第5期30卷 132-133,175页

作者：刘宴兵李秉智重庆邮电学院计算机系重庆400065

IP Quality of Service (QoS) guarantee is realized by managing and avoiding congestion in network. In thispaper ,the primary queue algorithms are compared in managing congestion. On the basis of these theories, a newLL... 详细信息

关键词： Internet 宽带IP网络队列调度算法服务质量 QoS 计算机网络

Solubility Diagrams of Aqueous Na+,Rb+,Cs+ // SO42--H2O,Rb+,Cs+,Mg2+//SO42--H2O and Rb+,Cs+ //Cl-,SO42--H2O Systems at 298.15K

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Solubility Diagrams of Aqueous Na+,Rb+,Cs+ // SO42--H2O,Rb+,...