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Synthesis of spherical nano-ZSM-5 zeolite with intergranular mesoporous for alkylation of ethylbenzene with ethanol to produce m-diethylbenzene

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Chinese Journal of Chemical Engineering 2024年第3期67卷 298-309页

作者： Siyue Wang Jinhong Li Qingxin Xu Shengjie Song Yu'ni Jiang Lidong Chen Xin Shi weiguo cheng Faculty of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 110629China Beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to develop efficient and stable heterogeneous ***,the spherical nano-ZSM-5 zeolite with abundant intergranular mesoporous is synthesized by the seed-mediated growth method for alkylation of EB with ethanol to produce *** results show that the spherical nano-ZSM-5 zeolite exhibits better stability and higher alkylation activity at a lower temperature than those of commercial micropore *** then,the spherical nano-ZSM-5 is further modified by La_(2)O_(3) through acid treatment followed by immersion *** acid treatment causes nano-ZSM-5 to exhibit the increased pore size but decreased the acid sites,and subsequent La_(2)O_(3) loading reintroduces the weak acid *** a result,the HNO_(3)-La_(2)O_(3)-modified catalyst exhibits a slight increase in EB conversion and DEB yield in comparison with unmodified one,and meanwhile,it still maintains high m-DEB *** catalyst after acid treatment achieves higher catalytic stability besides maintaining the high alkylation activity of EB with *** present study on the spherical nano-HZSM-5 zeolite and its modification catalyst with excellent alkylation ability provides new insights into the production of mDEB.

关键词： Zeolite Modification Alkylation reaction m-diethylbenzene Catalyst Fixed-bed

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采用分组模型的高比转速离心风机改进设计

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流体机械 2024年第3期52卷 81-88页

作者：成伟国秦国良雷健封昂西安交通大学能源与动力工程学院西安710049

为了提升某高比转速离心风机的气动性能,采用分组设计的方法,结合试验和数值模拟依次对原始风机的叶轮、蜗壳和集流器进行了改进设计。结果表明:叶轮前盘型线对高比转速离心风机的气动性能影响较大,仅对叶轮前盘型线改进设计后,风机的... 详细信息

为了提升某高比转速离心风机的气动性能,采用分组设计的方法,结合试验和数值模拟依次对原始风机的叶轮、蜗壳和集流器进行了改进设计。结果表明:叶轮前盘型线对高比转速离心风机的气动性能影响较大,仅对叶轮前盘型线改进设计后,风机的全压和效率分别提升了9.64%和8.91%;双圆弧叶片相较于单圆弧叶片具有更高的设计自由度,可实现对叶轮内部流动更加精细的控制,当双圆弧叶片的相对半径系数和相对叶片角系数分别取0.7和0.3时,全压效率值为87.43%;经过分组改进设计后的风机在设计工况下的全压和全压效率较原始风机分别提升了17.84%和12.79%,最高效率值为88.58%,内部流场得到优化,流动损失明显减小,性能得到全面提升。采用分组模型的改进设计方法可以有效地提升离心风机的气动性能,具有实际工程应用价值。

关键词：离心风机高比转速分组模型改进设计

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Spatiotemporal characteristics of the expansion of an urban agglomeration and its effect on the eco-environment: Case study on the northern slope of the Tianshan Mountains

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Science China Earth Sciences 2019年第9期62卷 1461-1472页

作者： Chuanglin FANG Qian GAO Xiaolei ZHANG weiguo cheng Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China College of Resources and Environmental Science Xinjiang University Urumqi 830046 China Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

Urban agglomerations, which are highly integrated urban groups, form during the advanced stages of industrialization and urban development. The urban agglomeration on the northern slope of the Tianshan Mountains is one of the 19 urban agglomerations promoted by China’s 13th Five-Year Plan and a key area of urbanization in Xinjiang. Based on remote sensing data, we analyzed the expansion of construction land in the urban agglomeration on the northern slope of the Tianshan Mountains and its effect on ecological value in 1980–2015. The results show that the expansion of construction land significantly affected ecological value in the study area over the past 35 years. Among land use types, grassland was the dominant contributor to changes in ecological value;its contribution rate reached 66.27% with an interannual variation of only 5%. The contribution rate of urban and rural residential land along with industrial and mining lands was very low(0.82%), while the interannual variation was large(86%). The area of construction land in the urban agglomeration expanded from 1,067 to 2,586 km^2, and the conversions of different land use types had different effects on ecological value. Among land use types, the conversions of lowcoverage grassland and dry land made the largest contributions to changes in ecological value. During the study period, a total of 1,685 km^2 of ecological land, 69.91% of which belonged to cultivated land and grassland, was converted into construction land.A total area of 1,082 km^2 of dry land and low-coverage grassland was converted into construction land, accounting for 64.21% of the total ecological land that was converted into construction land. In 2000–2015, the area of urban construction land increased significantly along with the proportion of unused land, including gobi(172 km^2), bare land(65 km^2), and salt-affected land(65 km^2), being converted into construction land. In contrast, the area of construction land that was converted into ecol

关键词： Urban agglomeration Tianshan Mountains Spatial expansion Temporal and spatial evolution Ecological environmental effect

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Study of image reconstruction using dynamic grids in tomographic gamma scanning

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Nuclear Science and Techniques 2012年第5期23卷 277-283页

作者： LIU cheng GU weiguo QIAN Nan WANG Dezhong School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China

In this paper, a new image reconstruction algorithm employing dynamic grids technique is proposed for tomographic gamma scanning. The key feature of the algorithm is the use of adaptive grid refinement in areas that indicate large values. Simulation results show that the application of dynamic grids has a good performance in emission reconstruction with a distinct advantage in the accurate positioning of the 'hot spots' and reducing the number of grids, but doesn't achieve a tangible improvement in transmission reconstruction.

关键词：层析γ扫描动态网格图像重建网格技术网格细化仿真结果准确定位自适应

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Glycerol carbonate synthesis from glycerol and dimethyl carbonate using guanidine ionic liquids

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Chinese Journal of Chemical Engineering 2017年第9期25卷 1182-1186页

作者： Xingxing Wang Peng Zhang Penglei Cui weiguo cheng Suojiang Zhang Beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process Engineering State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences

A large number of surplus glycerol from the biodiesel production can be used as renewable feedstock to produce glycerol carbonate. In this paper, a series of guanidine-based ionic liquids were synthesized to catalyze the transesterification of glycerol and dimethyl carbonate. The tunable basicity and the anion–cation cooperative effect were responsible for the obtained results. The [TMG][TFE] showed the best activity turnover frequency(TOF)of 1754.0 h^(-1), glycerol(GL) conversion of 91.8%, glycerol carbonate(GC) selectivity of 95.5%) at 80 °C with 0.1 mol% catalyst for 30 min. The reaction mechanism of the transesterification was also proposed.

关键词： Guanidine-based ionic liquids Glycerol carbonate Transesterification

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Uncertainty analysis of hydrological model parameters based on the bootstrap method:A case study of the SWAT model applied to the Dongliao River Watershed,Jilin Province,Northeastern China

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Science China(Technological Sciences) 2014年第1期57卷 219-229页

作者： ZHANG Zheng LU WenXi CHU HaiBo cheng weiguo ZHAO Ying Key Laboratory of Groundwater Resources and Environment Ministry of Education College of Environment and ResourcesJilin University

As an important tool for the description and analysis of hydrological processes,the watershed hydrological model has been increasingly applied to watershed hydrological simulations and water resource ***,in most cases,model parameters are only determined in a calibration scheme which fits the modeled data to observations,thus significant uncertainties exist in the model *** to quantitatively evaluate the uncertainties in model parameters and the resulting uncertainty impacts on model simulations has always been a question which has attracted much *** this study,two methods based on the bootstrap method(specifically,the model-based bootstrap and block bootstrap)are used to analyze the parameter uncertainties in the case of the SWAT(Soil and Water Assessment Tool)model applied to a hydrological simulation of the Dongliao River ***,the uncertainty ranges of five sensitivity parameters are *** calculated variation coefficients and the variable parameter contributions show that,among the five parameters,ESCO and CN2 have relatively high uncertainties:the variation coefficients and contribution rates are 23.98 and 70%,14.43 and 18%,*** three remaining parameters have relatively low *** compare the two uncertainty ranges of parameters acquired by the two bootstrap methods,and find that the uncertainty ranges of parameters acquired by the block bootstrap are narrower than those acquired by the model-based *** analysis of the effects of parameter uncertainties on the model simulation reveals that the parameter uncertainties have great impacts on results of the model simulation,and in the model calibration stage 60%70%of runoff observations were within the corresponding 95%confidence *** uncertainty in the model simulation during the flood season(*** wet period)is relatively higher than that during the dry season.

关键词：不确定性分析模型应用东辽河流域水文过程 SWAT 模型参数自举法吉林省

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Effect of vegetation type, wetting intensity, and nitrogen supply on external carbon stimulated heterotrophic respiration and microbial biomass carbon in forest soils

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Science China Earth Sciences 2015年第6期58卷 1446-1456页

作者： WU HaoHao XU XingKai DUAN CunTao LI TuanSheng cheng weiguo State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences College of Earth Science and Resources Chang'an University Faculty of Agriculture Yamagata University

By using packed soil-core incubation experiments,we have studied stimulating effects of addition of external carbon(C)(glucose,6.4 g Cm^(-2))on heterotrophic respiration and microbial biomass C of a mature broadleaf and Korean pine mixed forest(BKPF)and an adjacent white birch forest(WBF)soil under different wetting intensities(55%and 80%WFPS,water-filled pore space)and nitrogen(N)supply(NH_4C1 and KNO_3,4.5 g Nm^(-2))*** results showed that for the control,the cumulative carbon dioxide(CO_2)flux from WBF soil during the 15-day incubation ranged from 5.44 to 5.82 g CO_2-Cm^(-2),which was significantly larger than that from BKPF soil(2.86 to 3.36 g CO_2-Cm^(-2)).With increasing wetting intensity,the cumulative CO_2 flux from the control was decreased for the WBF soil,whereas an increase in the CO_2 flux was observed in the BKPF soil(P<0.05).The addition of NH_4C1 or KNO_3 alone significantly reduced the cumulative CO_2 fluxes by 9.2%-21.6%from the two soils,especially from WBF soil at low wetting *** addition of glucose alone significantly increased soil heterotrophic respiration,microbial biomass C(MBC),and microbial metabolic *** glucose-induced cumulative CO_2 fluxes and soil MBC during the incubation ranged from 8.7 to 11.7 g CO_2-Cm^(-2)and from 7.4 to 23.9 g Cm^(-2),which are larger than the dose of added ***,the addition of external carbon can increase the decomposition of soil native organic *** glucose-induced average and maximum rates of CO_2 fluxes during the incubation were significantly influenced by wetting intensity(WI)and vegetation type(VT),and by WI×VT,NH_4Cl×VT and WI×VT×NH_4Cl(P<0.05).The addition of NH_4C1,instead of KNO_3 significantly decreased the glucose-induced MBC of WBF soil(P<0.05),whereas adding NH_4C1 and KNO_3 both significantly increased the glucose-induced MBC of BKPF soil at high moisture(P<0.05).According to the differences in soil labile C pools,MBC and CO_2 fluxes in the presence and absence of

关键词：土壤异养呼吸土壤湿润微生物量碳植被类型外加碳源湿强度氮源土壤微生物生物量碳

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Effects of imidazolium-based ionic liquids on the isobaric vapor–liquid equilibria of methanol+dimethyl carbonate azeotropic systems

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Chinese Journal of Chemical Engineering 2020年第3期28卷 766-776页

作者： Songsong Chen Li Dong Junping Zhang weiguo cheng Feng Huo Qian Su Wei Hua Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of Sciences.Beijing 100090China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China SINOPEC Beijing Yanshan CompanyBeijing 102500China Dalian National Laboratory for Clean Energy Dalian 116023China

The separation of methanol(MeOH)and dimethyl carbonate(DMC)is important but difficult due to the formation of an azeotropic *** this work,isobaric vapor–liquid equilibrium(VLE)data for the ternary systems containing different imidazolium–based ionic liquids(ILs),***+DMC+1-butyl-3-methy-limidazolium bis[(trifluoromethyl)sulfonyl]imide([Bmim][Tf2N]),MeOH+DMC+1-ethyl-3-methyl-imidazolium bis[(trifluoromethyl)sulfonyl]imide([Emim][Tf2N]),and MeOH+DMC+1-ethyl-3-methylimidazolium hexafluorophosphate([Emim][PF6])were measured at 101.3 *** mole fraction of IL was varied from0.05 to *** experimental data were correlated with the NRTL and Wilson equations,*** results show that imidazolium-based ILs were beneficial to improve the relative volatility of MeOH to DMC,and[Bmim][Tf2 N]showed a much more excellent performance on the activity coefficient of *** interaction energies of system components were calculated using Gaussian program,and the effects of cation and anion on the separation coefficient of the azeotropic system were discussed.

关键词： Vapor liquid equilibria Ionic liquid Azeotrope Separation Interaction energy

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RAD51B-AS1 promotes the malignant biological behavior of ovarian cancer through upregulation of RAD51B

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第7期25卷 581-593页

作者： Xinyi WEI Conghui WANG Sangsang TANG Qian YANG Zhangjin SHEN Jiawei ZHU Xiaodong cheng Xinyu WANG Xing XIE Junfen XU weiguo LU Women's Reproductive Health Laboratory of Zhejiang Province Women�s HospitalZhejiang University School of MedicineHangzhou 310006China Department of Gynecologic Oncology Women�s HospitalZhejiang University School of MedicineHangzhou 310006China Cancer Center Zhejiang UniversityHangzhou 310058China Department of Obstetrics and Gynecology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Zhejiang Provincial Clinical Research Center for Obstetrics and Gynecology Hangzhou 310006China

Long non-coding RNAs(lncRNAs)play an indispensable role in the occurrence and development of ovarian cancer(OC).However,the potential involvement of lncRNAs in the progression of OC is largely *** investigate the detailed roles and mechanisms of RAD51 homolog B-antisense 1(RAD51B-AS1),a novel lncRNA in OC,reverse transcription-quantitative polymerase chain reaction(RT-qPCR)was performed to verify the expression of *** proliferation,metastasis,and apoptosis were detected using the cell counting kit-8(CCK-8),colony-formation,transwell,and flow cytometry *** xenograft models were established for the detection of *** results revealed that RAD51B-AS1 was significantly upregulated in a highly metastatic human OC cell line and OC ***51B-AS1 significantly increased the proliferation and metastasis of OC cells and enhanced their resistance to *** prediction analysis revealed that the only target gene of RAD51B-AS1 was *** gene function experiments revealed that RAD51B exerts the same biological effects as *** experiments demonstrated that the malignant biological behaviors promoted by RAD51B-AS1 overexpression were partially or completely reversed by RAD51B silencing in vitro and in ***,RAD51B-AS1 promotes the malignant biological behaviors of OC and activates the protein kinase B(Akt)/B cell lymphoma protein-2(Bcl-2)signaling pathway,and these effects may be associated with the positive regulation of RAD51B ***51B-AS1 is expected to serve as a novel molecular biomarker for the diagnosis and prediction of poor prognosis in OC,and as a potential therapeutic target for disease management.

关键词： Ovarian cancer(OC) Long non-coding RNA(LncRNA) Metastasis Anoikis

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An Efficient and Stable Ionic Liquid System for Synthesis of Ethylene Glycol via Hydrolysis of Ethylene Carbonate

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Chinese Journal of Chemical Engineering 2010年第6期18卷 962-966页

作者： MENG Zhenying SUN Jian WANG Jinquan ZHANG Jianxin FU Zengzeng cheng weiguo ZHANG Xiangping State Key Laboratory of Multiphase Complex System Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100049 China College of Chemistry and Chemical Engineering Henan Universitv Kaifeng 475001 China School of Chemical and Environmental Engineering China University of Mining & Technology (Beijing) Beijing 100083 China

An ionic liquid system of [Bmim]X/[Bmim]OH(X Cl,BF4,and PF6,) was developed for the hydroly-sis of ethylene carbonate to ethylene glycol. The important parameters,such as the variety of ionic liquids,molar ratio of [Bmim]X to [Bmim]OH,amount of ionic liquid,molar ratio of water to ethylene carbonate,reaction tem-perature,pressure and reaction time,were investigated systematically. Excellent yield(>93%) and high selectivity(99.5%) of ethylene glycol were achieved. Under the optimum reaction conditions,the ionic liquid system could be reused at least five times and the selectivity of ethylene glycol remained higher than 99.5%.

关键词：离子液体水解乙烯碳酸醇合成稳定最佳反应条件可重复使用

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