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Kinetics of non-catalyzed hydrolysis of tannin in high temperature liquid water

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第5期9卷 401-406页

作者： li-li LU Xiu-yang LU Nan MA Institute of Pharmaceutical Engineering Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China

High temperature liquid water(HTLW) has drawn increasing attention as an environmentally benign medium for organic chemical reactions,especially acid-/base-catalyzed reactions. Non-catalyzed hydrolyses of gallotannin and tara tannin in HTLW for the simultaneous preparation of gallic acid(GA) and pyrogallol(PY) are under investigation in our laboratory. In this study,the hydrolysis kinetics of gallotannin and tara tannin were determined. The reaction is indicated to be a typical consecutive first-order one in which GA has formed as a main intermediate and PY as the final product. Selective decomposition of tannin in HTLW was proved to be possible by adjusting reaction temperature and time. The present results provide an important basic data and reference for the green preparation of GA and PY.

关键词： High temperature liquid water Gallotannin Tara tannin Non-catalyzed hydrolysis Kinetics

Synthesis and Characterization of Temperature-sensitive Cellulose-graftPoly(N-isopropylacrylamide) Copolymers

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Chinese Journal of Polymer Science 2015年第12期33卷 1640-1649页

作者： li-li yang Jin-ming Zhang Jia-song He 张军甘志华 Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Engineering Plastics Institute of ChemistryChinese Academy of Sciences (CAS) University of Chinese Academy of Sciences State Key Laboratory of Organic-inorganic Composites Beijing Laboratory of Biomaterials College of Life Science and Technology Beijing University of Chemical Technology

A new series of cellulose-graft-poly（N-isopropylacrylamide）（cellulose-g-PNIPAM） copolymers were prepared by atom transfer radical polymerization （ATRP） of N-isopropylacrylamide monomers from a cellulose-based macro-initiator, which was homogeneously synthesized in an ionic liquid 1-allyl-3-methylimidazolium chloride （AmimC1）. The composition of cellulose-g-PNIPAM copolymers could be adjusted by altering the feeding ratio and reaction time. The resultant copolymers with relatively high content of PNIPAM segments （molar substitution of PNIPAM ≥ 18.3） were soluble in water at room temperature. Aqueous solutions of cellulose-g-PNIPAM copolymers exhibited clear temperature-sensitive behavior, and their sol-to-gel phase transition properties were investigated by dynamic light scattering （DLS） and UV measurements. Compared with pure PNIPAM, the cellulose-g-PNIPAM copolymers possessed higher lower critical solution temperatures （LCST） in a range from 36.9 ℃ to 40.8 ℃, which are close to normal human body temperature, and could be tuned by adjusting the content of PNIPAM segments in copolymers. Spherical structure of cellulose-g-PNIPAM copolymers formed at temperatures above LCST and its morphology was observed by TEM and SEM. These novel cellulose-g-PNIPAM copolymers may be attractive substrates for some biomedical applications, such as drug release and tissue engineering.

关键词： Cellulose-g-PNIPAM ATRP Temperature-sensitive Water soluble.

Effects of Headgroups and Serum on Gene Transfection of Alkaline Amino Acid Based Cationic lipids

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Chemical Research in Chinese Universities 2009年第1期25卷 69-71页

作者： li li yang yang NIE Yu HE Bin GU Zhong-wei National Engineering Research Center for Biomaterials Sichuan University Chengdu 610064 P. R. China

Three cationic lipids with lysylated（1）, histidylated（2）, and arginylated（3） headgroups and cholesterol hydrophobic moiety were synthesized. The average sizes of liposomes and lipoplexes were around 100 and 160 nm, respectively. The gene transfection efficiency of the three lipoplexes loaded with pGL3 or pORF-LacZ was compared on 293T cells in the presence or the absence of serum. The transfection efficiency of the three lipoplexes in a serum-free medium was 2 to 3-fold higher than that of dioleoyl-trimethylammonium propane（DOTAP）. In the presence of serum, however, most of the lipoplexes showed lower transfection activities; only lipoplex 3 retained its high transfection efficiency.

关键词： Cationic lipids Alkaline amino acids Serum Gene delivery Transfection efficiency

Thermodynamic Calculation of Inclusion Formation in Mg-Al-Si-O System of 430 Stainless Steel Melts

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Journal of Iron and Steel Research International 2011年第2期18卷 14-17页

作者： JIANG Zhou-hua li Shuang-jiang li yang School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China

A phase diagram was drawn through thermodynamic calculation to understand the equilibrium conditions of 2MgO · SiO2 , MgO · Al2O3 , 3Al2O3 · 2SIO2, and 2MgO·2Al2O3 · 5SiO2 formation in Mg-AI-Si-O system of 430 stainless steel melts at 1873 K. Further, the thermodynamic formation and transformation conditions of MgO · Al2O3 inclusion were discussed. The following results are obtained when ws, =0.26% and wo = 1.0 × 10^-5 in molten steel. The uniphase cordierite inclusion is difficult to exist stably; MgO· At203 inclusion cannot he formed in case of wAl being less than 1× 10^- 6 ; 3Al2O3 · 2SiO2 would change to MgO· Al2O3 and 2MgO · SiO2 in turn with increasing the Mg content when wAl is above 1.7× 10^- 6 ; with the formation of MgO · Al2O3 inclusion, A1 content increases with increasing Mg content when wMg is over 1. 7 × 10^- 9. For equilibrium condition and calculated steel composition, 2MgO·SiO2 inclusion would be formed ultimately and MgO · Al2O3 is almost inexistent.

关键词： phase diagram thermodynamic calculation MgO · Al2O3 inclusion 430 stainless steel

Effect of Boron Mud and CaF_2 on Surface Tension and Density of CaO-SiO_2-B_2O_3 Ternary Slag Systems

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Journal of Iron and Steel Research International 2014年第8期21卷 745-748页

作者： li-li yang Hong-ming WANG Xiang ZHU Gui-rong li School of Materials Science and Engineering Jiangsu University Jiangsu Province Key Laboratory of High-End Structural Materials

The effect of boron mud and CaF2,which were used as fluxing agents,on surface tension and density of CaO-SiO2-B2O3 ternary slag systems was *** surface tension and density were measured by using the ring detachment method and Archimedean method,*** results indicated that surface tension and density of the slag systems decreased with increasing temperature in the range of 1380-1480℃.When 5%-10% CaF2 was employed as fluxing agent,the surface tension and density of slag were decreased with increasing CaF2 content,and the surface tension changed from 0.3to 0.6N/m,while the density changed from 3.4to 4.1g/***,when using 5%-10%boron mud as fluxing agent,the surface tension was enhanced,whereas the density decreased with the increase of boron mud content,and the variation range was 0.4-0.6N/m for surface tension and 3.2-3.9g/cm3 for the *** a conclusion,using boron mud as fluxing agent to substitute for CaF2 did not cause significant changes in slag surface tension and density.

关键词： boron mud calcium fluoride surface tension density

ZrCl_4/Hantzsch 1,4-dihydropyridine as a new and efficient reagent combination for the direct reductive amination of aldehydes and ketones with weakly basic amines

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Chinese Chemical Letters 2007年第4期18卷 458-460页

作者： Zhen Gang liu Nan li li yang Zhong li liu Wei Yu State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China

ZrCl4/Hantzsch 1,4-dihydropyridine is a mild and highly efficient reagent combination for the direct reductive amination. Weakly basic amines such as anilines substituted by electron-withdrawing group and heteroaromatic amines can be reductively alkylated with electron rich aldehydes and ketones under mild conditions to form the secondary amines in excellent yields.

关键词： Zirconium tetractfloride Hantzsch 1,4-dihydropyfidine Reductive amination

Elevated serum levels of ghrelin and TNF-a in patients with cyanotic and acyanotic congenital heart disease

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World Journal of Pediatrics 2017年第2期13卷 122-128页

作者： Sai Zhang Gong-liang Guo li-li yang li-Qun Sun Outpatient Department of Pediatrics No.1 Hospiml of Jilin UniversityChangchunChina Department of Cardiology the Third Hospital ofJilin UniversityChangchunChina Department of Gynecology and Obstetrics No.1 Hospital of Jilin UniversityChangchunChina

Background:The levels of ghrelin and tumor necrosis factor alpha (TNF-a) are considered biological markers of congenital heart diseases (CHD).The present meta-analysis was conducted to investigate the clinical significance of serum levels of ghrelin and TNF-α in children with (CHD).Methods:Chinese and English scientific literature databases were searched to retrieve published studies relevant to ghrelin,TNF-α and *** search was additionally employed to identify other relevant studies from *** retrieved studies were screened on the basis of our stringent inclusion and exclusion criteria to select high quality case-control studies for ***:We initially retrieved 108 published studies (20 in Chinese and 88 in English) from database ***,6 case-control studies (5 in English and 1 in Chinese) were enrolled in our meta-analysis,and contained a total of 160 cyanotic congenital heart disease (CCHD) patients and 215 acyanotic congenital heart disease (ACHD) patients,along with 162 healthy *** results of meta-analysis showed that serum levels of ghrelin and TNF-α in CCHD or ACHD children were significantly higher than those in healthy ***:Our meta-analysis results showed that serum levels of ghrelin and TNF-α are elevated in children with CHD,and could be used as effective biologic markers in early diagnosis of CHD.

关键词： acyanotic congenital heart disease cyanotic ghrelin meta-analysis TNF-α

The Filament Eruption of 1999 March 21 and Its Associated Coronal Dimmings and CME

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Chinese Journal of Astronomy and Astrophysics 2006年第3期6卷 345-353页

作者： Yun-Chun Jiang Le-Ping li li-Heng yang National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011

We report a filament eruption near the center of the solar disk on 1999 March 21, in multi-wavelength observations by the Yohkoh Soft X-Ray Telescope （SXT）, the Extremeultraviolet Images Telescope （EIT） and the Michelson Doppler Imager （MDI） on the Solar and Heliospheric Observatory （SOHO）. The eruption involved in the disappearance of an Ha filament can be clearly identified in EIT 195A difference images. Two flare-like EUV ribbons and two obvious coronal dimming regions were formed. The two dimming regions had a similar appearance in lines formed in temperature range 6×10^4 K to several 10^6 K. They were located in regions of opposite magnetic polarities near the two ends of the eruptive filament. No significant X-ray or Hα flare was recorded associated with the eruption and no obvious photospheric magnetic activity was detected around the eruptive region, and particularly below the coronal dimming regions. The above surface activities were closely associated with a partial halo-type coronal mass ejection （CME） observed by the Large Angle and Spectrometric Coronagraphs （LASCO） on the SOHO. In terms of the magnetic flux rope model of CMEs, we explained these multiple observations as an integral process of largescale rearrangement of coronal magnetic field initiated by the filament eruption, in which the dimming regions marked the evacuated feet of the flux rope.

关键词： Sun: activity - Sun: filaments - Sun: coronal mass ejections(CMEs) - Sun:magnetic fields

Integration of a fused silica capillary and in-situ Raman spectroscopy for investigating CO_(2) solubility in n-dodecane at near-critical and supercritical conditions of CO_(2)

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Petroleum Science 2022年第6期19卷 3124-3133页

作者： Jun-liang Wang Zi-Hao Song lin-Jun li li-li yang Quan-Yuan Wang I-Ming Chou Zhi-Yan Pan College of Environment Zhejiang University of TechnologyHangzhouZhejiang310032China Hangzhou Academy of Environmental Protection HangzhouZhejiang310032China Laboratory for Experimental Study Under Deep-sea Extreme Conditions Institute of Deep-sea Science and EngineeringChinese Academy of SciencesSanyaHainan572000China

To determine the solubility of CO_(2)in n-dodecane at T=303.15-353.15 K,P≤11.00 MPa,an integrated fused silica capillary and in-situ Raman spectroscopy system was *** Raman peak intensity ratio(I_(CO_(2))/IC-H)between the upper band of CO_(2)Fermi diad(I_(CO_(2)))and the C-H stretching band of n-dodecane(IC-H)was employed to determine the solubility of CO_(2)in n-dodecane based on the calibrated correlation equation between the known CO_(2)molality in n-dodecane and the I_(CO_(2))/IC-Hratio with R^(2)=*** results indicated that the solubility of CO_(2)decreased with increasing temperature and increased with increasing *** maximum CO_(2)molality(30.7314 mol/kg)was obtained at 303.15 K and7.00 ***,a solubility prediction model(lnS=(P-A)/B)based on the relationship with temperature(T in K)and pressure(P in MPa)was developed,where S is CO_(2)molality,A=-8×10^(-6)T^(2)+0.0354T-8.1605,and B=*** results indicated that the solubilities of CO_(2)derived from this model were in good agreement with the experimental data.

关键词： CO_(2)solubility n-dodecane Raman spectroscopy Fused silica capillary In-situ