Phosphorus ligands for iron(III)-mediated ATRP of styrene via generation of activators by monomer addition

He, Dan,Xue, Zhigang,Khan, Mohd Yusuf,Noh, Seok Kyun,Lyoo, Won Seok Wiley Subscription Services, Inc., A Wiley Company 2010 Journal of polymer science Part A, Polymer chemist Vol.48 No.1

<P>Styrene polymerization via generation of activators by monomer addition (GAMA) for atom transfer radical polymerization (ATRP) has been examined extensively with bulk FeX<SUB>3</SUB> and FeX<SUB>2</SUB> at 110 °C in conjunction with various phosphorus-bearing ligands. It was found that GAMA possesses advantages over normal ATRP. Most importantly, narrower polydispersity index (PDI) values were observed from the styrene polymerizations with Fe(III) over those with Fe(II). Every instance of 2-(diphenylphosphino)-N,N′-dimethyl-[1,1′-biphenyl]-2-amine and 2-(diphenylphosphino) pyridine with the Fe(III) system were controlled excellently without addition of any radical initiator or reducing agent additives. Initiator type was found to exert a significant factor to influence on the controllability of polymerization. The initiation of 1-phenylethyl chloride and methyl-2-chloropropionate gave rise to formation of polymers with narrow PDI (1.05–1.20), whereas those from 1-phenylethyl bromide increased to 1.35. The GAMA of bulk styrene exhibited the best performance in terms of both rate and controllability compared with toluene and anisole. Both formation of block copolymer from the macroinitiator and efficient perturbation of polymerization with 2,2,6,6-tetramethylpiperidine 1-oxyl provided firm evidence to support the living and radical characteristics for the GAMA of styrene. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 144–151, 2010</P> <B>Graphic Abstract</B> <P>Styrene polymerization with iron(III) complexes with various phosphorus-containing ligands via generation of activators by monomer addition (GAMA) for atom transfer radical polymerization (ATRP) in the absence of any additive, is herein reported as a new ATRP method. The polymers formed in the GAMA of styrene have better controlled molecular weights and narrower polydispersities than normal ATRP under same conditions. The use of oxidatively stable catalysts can avoid the air-sensitive properties of lower-oxidation-state metals, and in addition, styrene acts as a in situ reducing agent to generate activators (Iron(II) species) as is showed in this mechanism diagram of GAMA of styrene. All the advantages of GAMA make this novel ATRP method much easier for practical production. <img src='wiley_img/0887624X-2010-48-1-POLA23772-gra001.gif' alt='wiley_img/0887624X-2010-48-1-POLA23772-gra001'> </P>

Enhanced Ionic Conductivity of Semi-IPN Solid Polymer Electrolytes Based on Star-Shaped Oligo(ethyleneoxy)cyclotriphosphazenes

He, Dan,Cho, Song Yun,Kim, Dong Wook,Lee, Changjin,Kang, Yongku American Chemical Society 2012 Macromolecules Vol.45 No.19

<P>A family of oligo(ethyleneoxy)cyclotriphosphazenes was synthesized as low molecular (or oligomeric) ionic conductors (plasticizer) and incorporated with lithium salt into semi-interpenetrating network (semi-IPN) solid polymer electrolytes (SPEs) for the improvement of ionic conductivity. A novel semi-IPN SPE was prepared by <I>in situ</I> radical polymerization of precursor solution containing a new cross-linker <B>PA6</B> and plasticizers <B>PME</B><SUB><B><I>n</I></B></SUB> (<I>n</I> = 2, 4, 6, 8) based on cyclotriphosphazenes, which exhibited high ionic conductivity of ca. 10<SUP>–4</SUP> S/cm at room temperature with significantly enhanced dimensional stability. The effect of the number of ethyleneoxy (EO) units in plasticizers, lithium salt concentration, and the content of the plasticizers on ionic conductivity of SPEs was investigated. The thermodynamic behaviors of the cyclotriphosphazene plasticizers were also analyzed to figure out the contribution of plasticizers to the improvements of electrochemical properties in the semi-IPN SPEs. Cyclic voltammetry and chronopotentiometry were conducted to confirm the electrochemical stability of this semi-IPN SPE system.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/mamobx/2012/mamobx.2012.45.issue-19/ma3016745/production/images/medium/ma-2012-016745_0013.gif'></P>

Electrochemical Properties of Semi-IPN Solid Polymer Electrolytes Based On muti-armed Oligo(ethyleneoxy) Cyclotriphosphazene

( He Dan ),조성윤,이창진,강영구 한국공업화학회 2011 한국공업화학회 연구논문 초록집 Vol.2011 No.1

Homicidal Poisoning of Heroin and Estazolam : Autopsy and Pathological Findings, Toxicological Analysis

Dan Liu,Shangxun Li,Xiangtao Ma,Jinxue Gao,Liang Xu,Jun He,Yuhong Li,Dan Yan,Yiwu Zhou,Qingming Wu 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.4

We reported an unusual homicidal case in which a 40-year-old woman was deceived into drinking a cup of milk that had 72 tablets of estazolam (2mg/tablet) dissolved in, and then being injected heroin aqueous solution on the right deltoid region by the criminal. At autopsy, pinpoint pupils and a new injection site on the right deltoid region were found. The pathologic pictures showed multiple patchy hemorrhages and considerable amounts of foreign amorphous substance with yellow appearance at the injection site. Some double refracting crystals with the forms of Maltese cross, acicular, rhomb or irregular were found by polarizing microscope, which may result from the diluent in heroin such as starch. Toxicological qualitative analysis by gas chromatography mass spectrometry (GC-MS) demonstrated the presence of benzodiazepine and morphine in blood and urine, and heroin in the injector left at scene. Quantitative analysis was also performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), providing the data on distribution of 6-monoacetylmorphine, morphine and estazolam in the woman’s body. And the cause of death was determined to polydrug heroin-related deaths due to the combined poisoning of heroin and estazolam. It taught a lesson that the determination of other drugs, particularly central nervous system depressants in heroin poisoning were quite important in forensic expertise.

Structural optimization of rapidly separating microneedles for efficient drug delivery

Dan Dan Zhu,Bo Zhi Chen,Meng Chan He,Xin Dong Guo 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.51 No.-

Rapidly separating microneedles (RSMNs) arose as an improvement of traditional MNs for the specialseparable structures. The aim of this study was to investigate various structural parameters contributedto the delivery performance of RSMNs. The experimental results indicated that the optimized RSMNswith 500 mm-long solid PLA MNs, 250 mm-long overlap and 500 mm-long dissolving MNs delivered over95% of drugs within 30 s. In the in vivo diabetic mice treatment, insulin loaded optimized RSMNs reachedapproximately the same therapeutic effect on lowering the glucose in blood as injection, significantlybetter than traditional MNs.

Antitumor bioactivity of porphyran extracted from <i>Pyropia yezoensis</i> Chonsoo2 on human cancer cell lines

He, Dan,Wu, Siya,Yan, Liping,Zuo, Jihui,Cheng, Yang,Wang, Hanfei,Liu, Jian,Zhang, Xu,Wu, Mingjiang,Choi, Jong‐,il,Tong, Haibin John WileySons, Ltd 2019 Journal of the Science of Food and Agriculture Vol.99 No.15

<P><B>Abstract</B></P><P><B>BACKGROUND</B></P><P><I>Pyropia yezoensis</I>, rich in porphyran, is a medicine‐edible red alga. In the present study, the physicochemical characteristics, conformational states and antitumor activities of a novel porphyran extracted from the high‐yield algal strain <I>Pyropia yezoensis</I> Chonsoo2 and its two degraded derivatives by gamma irradiation were investigated.</P><P><B>RESULTS</B></P><P><I>Pyropia yezoensis</I> porphyran is a water‐soluble, triple‐helical sulfated hetero‐galactopyranose, named PYP. PYP was degraded by gamma irradiation at 20 kGy and 50 kGy, giving two low molecular weight derivatives comprising PYP‐20 and PYP‐50, respectively. PYP with a higher molecular weight has a solution conformation different from PYP‐20 and PYP‐50. Three porphyrans had no toxicity in normal human liver cells (HL‐7702) and showed antitumor effects on Hep3B, HeLa and MDA‐MB‐231. They had better antitumor against HeLa cells, exhibiting a similar inhibition ratio compared to 5‐fluorouracil, with PYP especially exhibiting a higher inhibition ratio than 5‐fluorouracil. With respect to HeLa cells, the different antitumor activities might be related to porphyran molecular weight and solution conformation. Furthermore, the HeLa cell cycle was blocked in the G2/M phase after PYP treatment, leading to cell proliferation inhibition. The induction of cell cycle arrest was related to the changes in the expression of p21, p53, Cyclin B1 and cyclin‐dependent kinase 1.</P><P><B>CONCLUSION</B></P><P><I>Pyropia yezoensis</I> porphyran, as applied to medicine and functional food, could potentially be used as a non‐toxic natural adjuvant in cancer therapy. © 2019 Society of Chemical Industry</P>

An Optimal Combined SVM Model for Short-term Wind Speed Forecasting

Bai, Dan-Dan,He, Jing-Han,Tian, Wen-Qi,Wang, Xiaojun,Tony, Yip 대한전기학회 2014 The Journal of International Council on Electrical Vol.4 No.4

A high precise wind speed forecasting method is one of current wind power research hotspots. This paper presented a combined wind speed forecasting model based on support vector machine (SVM) optimized by particle swarm optimization (PSO) using historical data of wind speed at the site. The model took the results of back propagation neural network (BPNN), radial basis function neural network (RBFNN), genetic neural network (GNN) and wavelet neural network (WNN) as the inputs, and adopted the actual wind speed as the output. Meanwhile, particle swarm optimization was used to optimize model parameters. Apply this model in hourly prediction of wind speed using historical data from a wind farm in Shanxi Province. It is observed that its prediction accuracy was not only higher than that of any of its single network but higher than traditional linear combined forecasting model and neural network combined forecasting model.

芻議戱曲音樂和近現代民族聲樂的發展與融合 ―以歌曲≪山鬼≫爲例

賀丹 ( He Dan ) 인문사회과학예술융합학회 2019 인문사회과학예술융합학회지 Vol.3 No.2

戏曲音乐作为中国传统文化中的精粹, 影响着中国传统文化和传统音乐的发展。随着时代的变迁, 戏曲音乐在其发展过程中与近现代民族声乐相互借鉴、融合。本文主要论述的是以歌曲龚琳娜版≪山鬼≫为例, 刍议戏曲音乐与近现代民族声乐的发展与融合。笔者在本文中使用文献研究法和总结归纳法, 通过收集歌曲≪山鬼≫以及近现代民族声乐与戏曲的发展历史文献, 进行整理、查阅、对比分析, 以及对龚琳娜演唱版本≪山鬼≫视频、音频在发音、声腔、舞台表演等方面进行深入分析, 总结论证近现代民族声乐与戏曲音乐在题材、唱腔、舞台表演、伴奏乐器四个方面的相互融合。从而呼吁歌唱者用辩证法看待戏曲音乐与民族声乐的融合与发展。 As the essence of Chinese traditional culture, opera music affects the development of traditional Chinese culture and traditional music. With the changes of the times, the opera music is learning from and integrating with the modern national vocal music in its development process. This article mainly discusses the development of the opera music and the modern national vocal music by taking the song Gong Linna's version of "Mountain Ghost" as an example. In this paper, the author uses the literature research method and the summary induction method to collect, review, compare and analyze the song “Mountain Ghost” and the historical literature of modern national vocal music and opera, and the video of Gong Linna’s singing version of “Mountain Ghost”. The audio is deeply analyzed in terms of pronunciation, voice chamber, stage performance, etc. The general conclusion is that the modern national vocal music and opera music are integrated in the four aspects of theme, aria, stage performance and accompanying instrument. Therefore, the singer is called to use dialectics to treat the integration and development of opera music and national vocal music.

Poly(ethyleneimine) functionalized organic-inorganic hybrid silica by hydrothermalassisted surface grafting method for removal of nickel(II)

Lu He,Hong-Bo Xu,Bing-Bing Wang,Dan-Dan Liu,Ke-Sen Qian 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.2

Poly(ethyleneimine)-functionalized organic-inorganic hybrid silica adsorbent was synthesized by hydrothermal-assisted surface grafting technique for the removal of Ni(II) ions from aqueous solution, and was characterizedby FT-IR, nitrogen adsorption and the static adsorption-desorption experiment method. The results indicated thatthe maximum static adsorption capacity of Ni(II) on poly(ethyleneimine)-functionalized hybrid silica adsorbent byhydrothermal heating method was 1.6 times as much as the conventional heating method. The poly(ethyleneimine)-functionalized hybrid silica adsorbent offered a fast kinetics for the adsorption of Ni(II), had a substantial binding capacityin the range of pH 4-8 and could be used repeatedly. The Langmuir adsorption model was more favorable thanthe Freundlich and Dubinin-Radushkevich adsorption models. The adsorption followed a pseudo-second-order modelcompared with pseudo-first-order model. Various thermodynamic parameters such as ΔGo, ΔHo and ΔSo indicated thatthe adsorption process was spontaneous and endothermic. The results showed that poly(ethyleneimine)-functionalizedhybrid silica adsorbent could be employed as an effective material for the removal of Ni(II) ions from aqueous solution.

Protein Associated with Adventitious Root Induction Analysis of Tree Peony (Paeonia suffruticosa Andr.) Plantlets In Vitro by Two-dimensional Electrophoresis and Mass Spectrometry

Dandan Zhang,Zheng Wang,Liyun Shi,Wenqian Shang,Zhenzhu Fu,Dan He,Song Lin He 한국화훼학회 2016 화훼연구 Vol.24 No.2

In the present study, the plantlets in vitro of Paeonia suffruticosa ‘Wu Long Peng Sheng’ were used as laboratory materials. The proteome during adventitious root induction process was investigated to sift the related proteins by two-dimensional electrophoresis and mass spectrometry. The results indicated that the protein spots were concentrated in the acidity gel region (pH 4 - 7) and the spots number had a dynamic change ranged from 373 to 462 at the process of root induction (0 – 7 d). 8 spots significantly changed were analyzed with a mass spectrometer and identified using associated software and databases. The peptide information of the 8 spots was similar to the ATP synthase β-subunit of P. suffruticosa (Spots 1 - 4 and 8), P. tenuifolia (Spots 5), P. californica (Spot 6) and P. brownie ( Spots 7) r espectiv ely. T he expression levels of protein spots 1, 4, 5, 6 and 7 was dramatically downregulated, and that of protein spots 2 and 3 had a slightly opposite tendency on the 3rd day. The obviously decreased period is particularly interesting as it was consistent with the induction period of adventitious root primordial of tree peony plantlet in vitro. The ATP synthase β-subunit could be consumed for assembling the ATP synthase in order to supply energy to the rooting process. Therefore, we speculated that the ATP synthase β-subunit was involved in adventitious root initiation of tree peony plantlets in vitro and we expect that further studies should be carried out in order to export its action mechanism.