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magnetic resonance Letters 2022年第2期2卷 91-106,I0003页

作者： Chunfa Li Ting Huang Yubin Bao Zhe Chen Guangxin Lin SABIC R&D Center(China)Co. LtdShanghai201319China SABIC Mount VernonUSIN47620USA

Side reaction pathways are observed to occur between antioxidants and peroxide during the processing of multiple resin grades mediated by controlled peroxide-induced degradation of impact *** the present work,the reaction mechanism and main by-products between antioxidants and peroxides were *** results demonstrate that peroxides greatly accelerate the decomposition reactions,and the free radicals formed from peroxide decomposition react with,for example,the antioxidant AO1010 to produce dehydrogenation of phenyl propionic unit(s)at the a position(cinnamic acid ester moiety),which generates a conjugated system leading to the increased color of the *** is the first time to confirm the cinnamic acid moiety's existence and report its NMR ***,this work confirms the dehydrogenation mechanism by comparison with different sterically hindered phenolic *** also systematically summarizes the oxidation and degradation mechanism of AO168 and AO1010 under air and peroxide environments,*** on present study,clear guidelines are obtained to improve the quality of polymeric products,especially the appearance and stability,during product development.

关键词： Peroxide Antioxidant Free radical Cinnamic acid ester Polypropylene

Separation of Acearylenes from High-Temperature Coal Tar

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Transactions of Tianjin University 2012年第5期18卷 378-383页

作者：周建石马全领宗志敏魏贤勇 Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education China University of Mining and Technology Jiangsu Huaxin Technology Co. Ltd

High-temperature coal tar was extracted with petroleum ether （PE） under ultrasonic irradiation and the extracts were analyzed with gas chromatograph/mass spectrometer. The acearylene fractions including acenaphthylene, aceanthrylene and cyclopentapyrene were enriched together and named E, which was then transferred to a car- tridge in Isolera-One flash chromatography. Three groups of compounds were eluted out with ethyl acetate/PE mixed solvent （volume ratio 1：9） and named E1, E2 and E3 according to their main components. Acenaphthylene accounted for 78.2% in El, aceanthrylene 71.6% in E2 and cyclopentapyrene 75.9% in E3, respectively. The three groups of acearylenes were purified by Sephadex LH-20 column chromatography with ethanol/cyclohexane mixed solvent （vol- ume ratio 1：4）, and then confirmed with nuclear magnetic resonance spectrometer. This method indicates that flash chromatography has a good effect on separating the compounds with a similar structnre after extraction under ultrasonic irradiation.

关键词： separation acearylenes coal tar

Feasibility study of computed vs measured high b-value(1400 s/mm2) diffusion-weighted MR images of the prostate

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World Journal of Radiology 2014年第6期6卷 374-380页

作者： Leonardo K Bittencourt Ulrike I Attenberger Daniel Lima Ralph Strecker Andre de Oliveira Stefan O Schoenberg Emerson L Gasparetto Daniel Hausmann CDPI Ressonancia Magnética Avenida das Américas 4666 Barra da Tijuca RJ 22631-000 Brazil Institute of Clinical Radiology and Nuclear Medicine University of Heidelberg University Hospital Mannheim The-odor-Kutzer-Ufer 1-3 68167 Mannheim Germany siemens Healthcare Brazil Avenida Mutinga 3800 Jardim Santo Elias SP 05110-902 Brazil siemens AG Healthcare Sector Henkestrasse127 D-91052 Erlangen Germany

AIM: To evaluate the impact of computed b = 1400 s/mm2(C-b1400) vs measured b = 1400 s/mm2(M-b1400) diffusion-weighted images(DWI) on lesion detection rate, image quality and quality of lesion demarcation using a modern 3T-MR system based on a small-field-of-view sequence(sFOV). METHODS: Thirty patients(PSA: 9.5 ± 8.7 ng/mL; 68 ± 12 years) referred for magnetic resonance imaging(MRI) of the prostate were enrolled in this study. All measurements were performed on a 3T MR *** DWI, a single-shot EPI diffusion sequence(b = 0, 100, 400, 800 s/mm2) was utilized. C-b1400 was cal-culated voxelwise from the ADC and diffusion images. Additionally, M-b1400 was acquired for evaluation and comparison. Lesion detection rate and maximum lesion diameters were obtained and compared. Image quality and quality of lesion demarcation were rated accord-ing to a 5-point Likert-type scale. Ratios of lesion-to-bladder as well as prostate-to-bladder signal intensity(SI) were calculated to estimate the signal-to-noise-ratio(SNR). RESULTS: Twenty-four lesions were detected on M-b1400 images and compared to C-b1400 images. C-b1400 detected three additional cancer suspicious lesions. Overall image quality was rated significantly better and SI ratios were significantly higher on C-b1400(2.3 ± 0.8 vs 3.1 ± 1.0, P < 0.001; 5.6 ± 1.8 vs 2.8 ± 0.9, P < 0.001). Comparison of lesion size showed no significant differences between C- and M-b1400(P = 0.22). CONCLUSION: Combination of a high b-value extrap-olation and sFOV may contribute to increase diagnostic accuracy of DWI without an increase of acquisition time, which may be useful to guide targeted prostate biopsies and to improve quality of multiparametric MRI(mMRI) especially under economical aspects in a pri-vate practice setting.

关键词： Prostate cancer magnetic resonance imag-ing Diffusion-weighted imaging Ultra-high b-values Extrapolated b-values

Effect of alkali-activation on aluminosilicate-based cementitious materials

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Journal of University of Science and Technology Beijing 2008年第6期15卷 796-801页

作者： Xiaoguang Yang Wen Ni Xufang Zhang Yali Wang School of Civil and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China Central Research Institute of Building and Construction Co. ltd. MCC Group Beijing 100088 China

High-performance aluminosilicate-based cementitious materials were produced with fly ash from a coal power plant as one of the major raw materials. The structures of fly ash containing aluminosilicate-based cementitious materials were compared before and after treatment by the methods of nuclear magnetic resonance （NMR） and scanning electron microscopy （SEM）. During the 28 d curing time, the compressive strength of water glass and fly ash samples increased from 9.08 MPa to 26.75 MPa. The results show that most of the stiff shells are destroyed after mechanical grinding and chemical activation. Magic angle spinning （MAS） NMR of 27Al shows that the wide peak becomes narrow and the main peak shifts to the direction of low field, indicating the decrease of polymerization degree, the enhancing of activity, the decrease of six-coordination structure, and the increase of small and symmet- rical four-coordination polyhedron structure within the aluminum-oxygen polyhedron network. Comparisons between MAS NMR of 29Si with different treatments suggest that QO disappears, the quantity of Q2 increases, and the quantity of Q4 decreases. The polymerization degree of silicon-oxygen is reduced, and the potential activity of fly ash is increased.

关键词： fly ash modification alkali activation water glass

Synthesis and Characterization of Novel Biodegradable Poly (butylene succinate-co-triethylene glycol succinate)Copolymers

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Journal of Beijing Institute of Technology 2017年第2期26卷 276-284页

作者： Jie Ouyang Hongquan Yin Qingshan Zhang Yunzheng Li Pengjun Yao . School of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China Anhui Sealong Biotechnology Co. Ltd Bengbu Anhui 233316 China

Novel biodegradable aliphatic polyesters,poly（butylene succinate-co-triethylene glycol succinate）（P（BS-co-TEGS））and poly（butylene succinate）（PBS）,were synthesized through a two-step procedure of esterification and polycondensation with succinic acid and1,4-butanediol/triethylene glycol as raw materials as well as tetrabutyl titanate and diphenylphosphinic acid as the *** chemical structure and molecular weight of the copolymers were characterized by 1^H nuclear magnetic resonance（1^H NMR）and gel permeation chromatography（GPC）,*** addition,thermal properties,crystal structure and mechanical properties were also analyzed with various techniques.P（BS-co-TEGS）exhibited more excellent mechanical properties than PBS,especially in elongation at ***,the crystal structure and thermal stability of the P（BS-co-TEGS）have hardly *** crystallinity of P（BS-co-TEGS）was lower than that of PBS and decreased with the increase of mole ratio of triethylene *** the increase of TEGS unit molar composition,the melting point（Tm）,crystallization temperatures（Tc）and heat of fusion（ΔHm）of P（BS-co-TEGS）decreased,while glass transition temperature（Tg）increased.

关键词： aliphatic polyesters polycondesation mechanical properties crystallinity

Oil Production Optimization by Means of a Combined“Plugging,Profile Control,and Flooding”Treatment:Analysis of Results Obtained Using Computer Tomography and Nuclear magnetic resonance

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Fluid Dynamics & Materials Processing 2022年第3期18卷 737-749页

作者： Yanyue Li Changlong Liu Wenbo Bao Baoqing Xue Peng Lv Nan Wang Hui Li Wenguo Ma Cnooc(China)Co. Ltd.Tianjin BranchTianjin300452China School of Petroleum Engineering Northeast Petroleum UniversityDaqing163318China

Due to long-term water injection,often oilfields enter the so-called medium and high water cut stage,and it is difficult to achieve good oil recovery and water reduction through standard methods(single profile control and flooding measures).Therefore,in this study,a novel method based on“plugging,profile control,and flooding”being implemented at the same time is *** assess the performances of this approach,physical simulations,computer tomography,and nuclear magnetic resonance are *** results show that the combination of a gel plugging agent,a polymer microsphere flooding agent,and a high-efficiency oil displacement agent leads to better results in terms of oil recovery with respect to the situation in which these approaches are used separately(the oil recovery is increased by 15.37%).Computer tomography scan results show that with the combined approach,a larger sweep volume and higher oil washing efficiency are *** remaining oil in the cluster form can be recovered in the middle and low permeability layer,increasing the proportion of the columnar and blind end states of the *** nuclear magnetic resonance test results show that the combined“plugging,profile control,and flooding”treatment can also be used to control more effectively the dominant channels of the high permeability layer and further expand the recovery degree of the remaining oil in the pores of different sizes in the middle and low permeability ***,for the low permeability layer(permeability difference of 20),the benefits in terms of oil recovery are limited.

关键词： “Plugging,profile control and flooding”measures computed tomography scan nuclear magnetic resonance remaining oil recovery ratio

Characterization of a novel impurity in bulk drug of lisinopril by multidimensional NMR technique

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第4期7卷 310-313页

作者： WANG Dan-hua PEI Sai-fen ZHOU Ming-hua SUN Cui-rong PAN Yuan-jiang Department of Chemistry Zhejiang University Hangzhou 310027 China Zhejiang Huahai Pharmaceutical Co. Ltd. Linhai 317024 China

During the routine impurity profile of lisinopril bulk drug by HPLC (high-performance liquid chromatography), a potential impurity was detected. Using multidimensional NMR (nuclear magnetic resonance) technique, the trace-level impurity was unambiguously identified to be 2-(-2-oxo-azocan-3-ylamino)-4-phenyl-butyric acid after isolation from lisinopril bulk drug by semi-preparative HPLC. Formation of the impurity was also discussed. To our knowledge, this is a novel impurity and not reported elsewhere.

关键词： Lisinopril Impurity Structural characterization NMR

Organosilane surfactant-assisted synthesis of mesoporous SSZ-39 zeolite with enhanced catalytic performance in the methanol-to-olefins reaction

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Frontiers of Chemical Science and Engineering 2020年第2期14卷 267-274页

作者： Hao Xu Chi Lei Qinming Wu Qiuyan Zhu Xiangju Meng Daniel Dai Stefan Maurer Andrei-Nicolae Parvulescu Ulrich Muller Fengshou Xiao Key Laboratory of Applied Chemistry of Zhejiang Province Department of ChemistryZhejiang UniversityHangzhou 310028China BASF Catalysts(Shanghai)Co. Ltd.Shanghai 201206China BASF SE Ludwigshafen 67056Germany

SSZ-39 zeolite with AEI framework structure is a good catalyst candidate for the methanol-to-olefins(MTO)***,the diffusion limitation and coke formation often results in fast deactivation of the SSZ-39 zeolite *** solution for this challenge is to introduce mesoporosity in the SSZ-39 ***,we report the synthesis of mesoporous SSZ-39 zeolite using an organosilane surfactant,,-dimethyl--(3-(trimethoxysilyl)propyl)octan-1-aminium chloride,as a mesopore template and,-dimethyl--2,6-dimethylpiperidinium as a micropore *** obtained zeolites were characterized by X-ray diffraction,N sorption,scanning electron microscopy,temperature programmed desorption of ammonia,and magic angle spinning nuclear magnetic resonance of *** results show that the mesoporous SSZ-39 zeolite has high crystallinity,meso/microporosity,high surface area,cuboid morphology,and abundant acidic *** importantly,this mesoporous SSZ-39 zeolite exhibits enhanced catalyst lifetime in the MTO reaction due to the presence of mesoporosity for fast mass transfer,compared with a conventional SSZ-39 zeolite without mesoporosity.

关键词： SSZ-39 zeolite mesopores organosilane surfactant MTO reaction soft template mass transfer

Shaped binderless ZSM-11 zeolite catalyst prepared via a dry-gel conversion method:Characterization and application for alkylation of benzene with dimethyl ether

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Journal of Energy Chemistry 2017年第3期26卷 380-389页

作者： Wanshuo Zhang Shuang Zhang Wenjie Xin Hui Liu Yongchen Shang Xiangxue Zhu Shenglin Liu Longya Xu College of Chemistry and Chemical Engineering Harbin Normal University State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences Research and Development Center Sinochem Quanzhou Petrochemical Co.Ltd.

Shaped binderless ZSM-11 zeolite catalysts were synthesized via a dry-gel conversion technique from 70ZSM-11/30 SiO;mix extrudates. 1,6-hexanediamine combined with tetrabutylammonium bromide was proved to be the best structure directing agent for the synthesis of the binderless ZSM-11 catalyst, without adding other alkaline materials. The 70HZSM-11/30 SiO;mix serials materials crystallized for different times were detected by X-ray diffraction（XRD）, nuclear magnetic resonance（NMR）, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, scanning transmission electron microscopy–energy dispersive spectroscopy（STEM–EDS） techniques, and so on. In order to investigate the possible crystallization mechanism, the textural and structural properties of 70HZSM-11/30 SiO;mix serials samples were further characterized by N;adsorption–desorption. Acid properties were determined by temperature-programed desorption of NH;（NH;-TPD） and pyridine adsorption-infrared（Py-IR） measurements. In the alkylation of benzene with dimethyl ether, the serials catalysts exhibited different benzene conversions. 70HZSM-11/30 SiO;mix showed the lowest benzene conversion while sample 70HZSM-11/30 SiO;mix-6.5h synthesized only for 6.5h displayed a higher benzene conversion, even higher than the value over 70HZSM-11/30Al;O;mix. Extending the crystallization time, the obtained samples displayed the increased benzene conversion in general under the same reaction conditions. In the end, the relation of physicochemical properties with the reaction performance was investigated.

关键词： Shaped binderless ZSM-11 Crystallization mechanism Mechanical strength Acidity Alkylation Dimethyl ether

Exploration of Waterproofness of Concrete and Alkali-Aggregate Using Hydrophobic Impregnation and Coating

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Journal of Renewable Materials 2022年第12期10卷 3521-3538页

作者： Shun Kang Xun Yuan Changwu Liu Yulin Chen Xianliang Zhou Haikuan Wu Zhiguo Ma College of Water Resource and Hydropower Sichuan UniversityChengduChina School of Emergency Science Xihua UniversityChengduChina Sichuan Chuanjiao Road and Bridge Co. Ltd.GuanghanChina

Part of the tunnel spoil can not be used for concrete due to alkali aggregate reaction(AAR).Water is an indis-pensable condition for AAR,so separating the alkali-aggregate from water is of great benefit to controlling the *** paper investigates the modification of concrete and aggregate by hydrophobic impregnation and organic coating and then evaluates their waterproof and me chanical properties by dynamic contact angle(DCA),ultrasonic wave velocity,scanning electron microscope(SEM),nuclear magnetic resonance(NMR),and so *** waterproofness,hydrophobic impregnation and organic coating can both improve the waterproof-ness of concrete and *** organic coating is suitable for aggregate because it wrap aggregate *** aggregate coated by PVA can improve the interfacial transition zone(ITZ).For mechanical properties,both mate-rials will weaken the strength of the ***,concrete made by aggregate with organic coating shows plastic deformation and has a good correlation with the film thickness,a plastic estimation model based on flm thickness is *** paper evaluates the waterproof of concrete and aggregate and finds plastic con-crete with good aggregate waterproofness which provides a new idea for the application of alkali aggregate in see-page control facilities of water conservancy projects.

关键词： Alkali aggregate SEM NMR PVA