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Monte Carlo Simulation on Layered Polymeric Films

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Chinese Journal of Polymer Science 2014年第5期32卷 595-602页

作者： ru xia xiang-song Wu 陈鹏 Jia-sheng Qian xiao-shuang Feng Anhui Province Key Laboratory of Environment-friendly Polymer Materials School of Chemistry and Chemical Engineering Anhui University Eco-Efficient Product & Process Laboratory (E2P2L) UMI 3464 Research & Innovation Center in Shanghai (RICS) Solvay(China) Co. Ltd.

Thin films of polymer blends composed of alternating copolymer, diblock copolymer and/or homopolymer are studied using Monte Carlo simulation. A multilayer morphology is observed in the film, that is, the blended polymers assemble into individual domains arranged from interior to the surfaces of the film. The coexisting components residing throughout the neighboring domains in the film make no distinguishable interface between any neighboring domains. By this means, it forms a vertical composition gradient in the polymeric film. Being different from layer-by-layer deposition of polyelectrolyte or hydrogen bonding approach etc., the layered structure in this study is formed by polymer blending in one step. Alternating copolymers are found to be essential components to form vertical composition gradient （layered structure） in thin films.

关键词： Monte Carlo simulation Polymer blends Alternating copolymer Layered structure.

Investigation of L/D-threonine substituted L-serine octamer ions by mass spectrometry and infrared photodissociation spectroscopy

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Chinese Chemical Letters 2017年第3期28卷 537-540页

作者： Juan Ren Yi-Yun Wang ru-xia Fenga xiang-Lei Kong The State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China Collaborative Innovation Center of Chemical Science and Engineering Nankai University Tianjin 300071 China

Threonine-substituted serine octamer ions were generated by electrospray ionization（ESI） and investigated by mass spectrometry and infrared photodissociation（IRPD） spectroscopy. IRPD spectra of[L-Ser_7＋ L/D-Thr_1]H~＋and [L-Ser_6＋ L/D-Thr_2]H~＋were obtained in the range of 2700–3600 cm^（-1）. Chiral differentiation was achieved by comparing their IRPD spectra. The main difference located in the range of 3300–3500 cm^（-1）. And the results indicate the substitution of L-Ser by D-Thr could weaken the intermolecular H-bonds and loosen the original structures of serine octamers.

关键词： IRPD spectroscopy Threonine Serine octamer Chiral differentiation Mass spectrometry

Grafting of thermoresponsive polymer from the surfaceof functionalized multiwalled carbon nanotubes via atom transfer radical polymerization

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Chinese Science Bulletin 2008年第15期53卷 2297-2306页

作者： XU GuoYong xia ru WANG Hu MENG xiangChun ZHU QingRen Center of Modern Experimental Technology Anhui University Hefei 230039 China Anhui Zhongding Share Co. Ltd. Ningguo 242300 China School of Chemistry & Chemical Engineering Anhui University Hefei 230039 China Hefei National Laboratory for Physical Sciences at the Microscale Structure Research Laboratory University of Science andTechnology of China Hefei 230026 China

Multiwalled carbon nanotubes were oxidized with concentrated HNO3 and H2SO4 to introduce carbox-ylic groups onto carbon nanotubes surfaces. The oxidized carbon nanotubes were reacted subse-quently with thionyl chloride and 2-Hydroxylethyl-2′-bromoisobutyrate, producing MWNT-based macroinitiators, MWNT-Br, for the atom transfer radical polymerization of (N-isopropylacrylamide). FTIR, XPS, 1H NMR, Raman and TGA were used to characterize the resulting products and to determine the content of the water-soluble poly (N-isopropylacrylamide) chains in the product. The MWNTs grafted with PNIPAM chains have good solubility in distilled water; THF and CHCl3. TEM images of the samples provide direct evidence for the formation of a nanostructure that MWNTs coated with polymer layer. The produced MWNT-g-PNIPAM has a PNIPAM shell, which is very sensitive to the change of temperature. This method would open a door for the fabrication of novel functional carbon nanotube-based nano-materials or nanodevices with designable structure and tailor-made properties.

关键词：碳纳米管 ATRP 官能高聚物化学反应

Structure of Pro_4H^＋ investigated by infrared photodissociation(IRPD) spectroscopy and theoretical calculations

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Chinese Chemical Letters 2016年第4期27卷 593-596页

作者： ru-xia Feng Lei Mu Shu-Mei Yang xiang-Lei Kong The State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China Collaborative Innovation Center of Chemical Science and Engineering Nankai University Tianjin 300071 China

Combining with electrospray ionization（ESI）mass spectrometry,infrared photodissociation（IRPD）spectroscopy is a powerful method to study structures of cluster ions in the gas *** this paper,infrared photodissociation spectrum of Pro_4H~＋in the range of 2700–3600 cm 1was obtained *** theoretically predicted spectra of the two most stable isomers of Pro4^（-1） and Pro4^（-2） obtained at the level of M062X/6-31＋G（d,p）are in good consistent with the experimental *** two isomers have similar structures and close *** of them only consist of zwitterionic units,indicating the strong salt-bridged interactions inside the *** the calculated collision cross section（ccs）of Pro4-1 is found to be very close to the experimental result previously reported.

关键词： IRPD spectroscopy Proline tetramer Theoretical calculations Structure FT ICR MS

A Green Synthesis of 2-Ethylanthraquinone by Dehydration of 2-(4'-ethylbenzoyl) benzoic Acid over Solid Acid Catalysts

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Chinese Chemical Letters 2005年第12期16卷 1587-1589页

作者： Ren Shu XU Xin Wen GUO Gui ru WANG Zhu xia ZHANG State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

The dehydration of 2-（4＇-ethylbenzoyl） benzoic acid （BE acid） to 2-ethylanthraquinone （2-EAQ） was investigated over solid acid catalysts. The results showed that H-beta zeolite catalyst modified by dilute HNO3 solution exhibited an excellent performance. In our study, the conversion of BE acid can reach 96.7%, and the selectivity to 2-EAQ is up to 99.6%.

关键词： 2-Ethylanthraquinone 2-(4'-ethylbenzoyl) benzoic acid H-beta dehydration

Trace determination of hexabromocyclododecane diastereomers in water samples with temperature controlled ionic liquid dispersive liquid phase microextraction

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Chinese Chemical Letters 2011年第1期22卷 97-100页

作者： ru Song Zhao xia Wang Jin Peng Yuan Shan Shan Wang Chuan Ge Cheng Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province Analysis and Test Center Shandong Academy of Sciences Jinan 250014 China

A novel temperature controlled ionic liquid dispersive liquid phase microextracfion （TCIL-DLPME） coupled with rapid resolution liquid chromatography-electrospray tandem mass spectrometry （RRLC-ESI-MS-MS） has been developed for the enrichment and determination of three hexabromocyclododecane diastereomers （HBCDs） in water samples. Green solvent ionic liquid （IL） was used as extraction solvent instead of toxic organic solvents. This technique also avoided the usage of dispersive solvent. Some important parameters that might affect the extraction efficiency were optimized. Under the optimum conditions, good linear relationship, sensitivity and reproducibility were obtained. All the limits of detection for the three diastereomers were 0.1 ng/ mL. The linear range was obtained in the range of 1-100 ng/mL for the total amount of three HBCD diastereomers. It was satisfactory to analyze real environmental water samples with the recoveries ranging from 77.2% to 99.3%. The main advantage of the method is toxic organic solvent-free.

关键词： Hexabromocyclododecane Temperature controlled ionic liquid dispersive liquid phase microextraction Rapid resolution liquidchromatography-electrospray tandem mass spectrometry

Real-time polymerase chain reaction for the diagnosis of necrotizing herpes stromal keratitis

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International Journal of Ophthalmology(English edition) 2016年第5期9卷 682-686页

作者： Jun-Xin Ma Lin-Nong Wang ru-xia Zhou Yang Yu Tong-Xin Du Department of Ophthalmology Nanjing First Hospital Nanjing Medical University Department of Clinical Nuclear Medicine Center Nanjing First HospitalNanjing Medical University

AIM： To design, optimize and validate a rapid,internally controlled real-time polymerase chain reaction（RT-PCR） test for herpes simplex virus（HSV） in the diagnosis of necrotizing herpes stromal keratitis.· METHODS： Tears alone or together with corneal epithelium scrapings from 30 patients（30 eyes）suspected of necrotizing herpes stromal keratitis were tested for HSV DNA by RT-PCR. The samples were collected during the first visit and then on the subsequent 7, 14, 28, 42, and 56 d. The symptoms of the patients were scored before treatment to determine the correlation between HSV concentration in the corneal epithelium scrapings and clinical scores.·RESULTS： The positive rate（46.4%） in the corneal epithelium group before the therapy was significantly higher than that（13.3%） in the tears group（P =0.006）.There were 13 positive HSV patients before the therapy,the concentration of HSV DNA in corneal epithelium scrapings group was significantly higher than that in the tears group（paired t-test, P =0.0397）. Multilevel mixedeffects model analysis showed that the difference between the corneal epithelium scrapings group and the tears group was statistically significant（P =0.0049）. The Spearman rank correlation analysis indicated a positive correlation between the HSV concentration in the corneal epithelium scrapings and clinical scores before the treatment（r =0.844, P〈 0.0001）.· CONCLUSION： RT-PCR appears to be a powerful molecular tool for the diagnosis of necrotizing herpes stromal keratitis.

关键词： necrotizingherpes stromal keratitis real-time polymerase chain reaction corneal epithelium scrapings tears

Hepatitis B core antigen modulates exosomal miR-135a to target vesicle-associated membrane protein 2 promoting chemoresistance in hepatocellular carcinoma

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World Journal of Gastroenterology 2021年第48期27卷 8302-8322页

作者： xiao-Cui Wei Ya-ru xia Ping Zhou Xing Xue Shuang Ding Li-Juan Liu Fan Zhu State Key Laboratory of Virology Hubei Province Key Laboratory of Allergy and ImmunologyDepartment of Medical MicrobiologySchool of MedicineWuhan UniversityWuhan 430071Hubei ProvinceChina

BACKGROUND Hepatocellular carcinoma(HCC)is one of the most common malignant *** association of hepatitis B virus(HBV)infection with HCC is hitherto *** miRNAs contribute to cancer progression and *** X protein has been known to modulate miRNAs that facilitate cell proliferation and the process of ***,there has been no report on hepatitis B core antigen(HBc)regulating exosomal miRNAs to induce drug resistance of HCC *** To elucidate the mechanism by which HBc promotes Doxorubicin hydrochloride(Dox)resistance in *** Exosomes were isolated by *** morphology and size of exosomes were evaluated by Dynamic Light Scattering(DLS)and transmission electron microscopy(TEM).The miRNAs differentially expressed in HCC were identified using The Cancer Genome Atlas(TCGA)*** level of miR-135a-5p in patient tissue samples was detected by quantitative polymerase chain *** and luciferase assay were used to predict and prove the target gene of ***,we identified the effects of miR-135a-5p on anti-apoptosis and the proliferation of HCC in the presence or absence of Dox using flow cytometry,Cell counting kit 8(CCK-8)assay and western *** We found that HBc increased the expression of exosomal *** analysis of bioinformatics and patient samples found that miR-135a-5p was increased in HCC tissues in comparison with paracancerous *** analysis and in vitro validation identified vesicle-associated membrane protein 2(VAMP2)as a novel target gene of *** assays showed that exosomal miR-135a-5p induced apoptosis protection,cell proliferation,and chemotherapy resistance in *** addition,the rescue experiment demonstrated that VAMP2 reversed apoptosis protection,cell growth,and drug resistance by ***,HBc promoted HCC anti-apoptosis,proliferation,and drug resistance and prevented Dox-i

关键词： Hepatocellular carcinoma Exosomes miR-135a-5p Anti-apoptosis Proliferation Chemoresistance

Lag of accommodation predicts clinically significant change of spherical equivalents after cycloplegia

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International Journal of Ophthalmology(English edition) 2021年第7期14卷 1052-1058页

作者： Cheng-Cheng Jin ru-xia Pei Bei Du Gui-Hua Liu Nan Jin Lin Liu rui-Hua Wei Tianjin Key Laboratory of Retinal Functions and Diseases Tianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China

AIM: To evaluate related factors with the change of spherical equivalents(ΔSE) and determine the suitable predictor of clinically significant ΔSE(≥0.50 D) with cyclopentolate hydrochloride on Chinese children. METHODS: A total of 145 right eyes of 145 children aged 4 to 15 y were enrolled. Intraocular pressure, axial length and lag of accommodation(LOA) were assessed before cycloplegia induced by 3 drops of 1% cyclopentolate at 5-minute intervals. SE was measured before and 1 h after the first drop of cyclopentolate. ΔSE was compared between different gender groups and among refractive groups. Multivariate linear regression analysis was performed to find related factors with ΔSE. ROC analysis was used to figure out the suitable predictor of clinically significant Δ***: For the total 145 eyes, the mean SE reached up to-0.70±1.86 D from-1.30±1.62 D, with the mean ΔSE of 0.60±0.55 D. The mean ΔSE were 0.63±0.55 D and 0.57±0.56 D respectively in the male and female group(P=0.40). The mean ΔSE was significantly different among different refractive groups(Pxial length and 86%(AUC=0.86) in association with axial length as well as ***: After cycloplegia with cyclopentolate, the ΔSE decreases with larger LOA, longer axial length and older age. Specifically, LOA plays a more vital role in predicting clinically significant ΔSE.

关键词： cycloplegia cyclopentolate spherical equivalent clinically significant change lag of accommodation