检索结果-南通市图书馆

Chinese Journal of Chemical Engineering 2024年第10期74卷 216-226页

作者： Peng Dong Yang Xin Yanwei Li Xiaohui Zhang Xiaorui Wang Yu Zhao Dongqiang Zhang Haowen Ma Guixian Li School of petrochemical Engineering Lanzhou University of TechnologyLanzhou 730050China Key Laboratory of Low Carbon Energy and Chemical Engineering of Gansu Province Lanzhou 730050China lanzhou petrochemical university of vocational technology Lanzhou 730060China lanzhou petrochemical Research Center Petrochemical Research InstitutePetroChina Company LimitedLanzhou 730060China

Hydroxylation of inert benzene through the activation of the C_(sp2)-H bond is a representative reaction about the transformation of C-H bonds to C-O bonds,which has far-reaching guiding significance but remains a challenging scientific *** overcome this problem,a series of VOx-Ga_(2)O_(3)/SiO_(2)-Al_(2)O_(3)were prepared to achieve an efficient and economical hydroxylation path of benzene to *** results showed that the phenol yield was 72.89%(selectivity>98.1%)under the optimum *** reason is that the C-H bond in the benzene ring is activated by heterolysis over a VOx-Ga_(2)O_(3)/SiO_(2)-Al_(2)O_(3)***,the introduction of aluminum(Al)and gallium(Ga)made a qualitative change in the catalyst,enhancing the electron motion and spin motion of vanadium species,resulting in the increase of V4^(+)/V5^(+)*** addition,the catalyst can provide an optimal acidic environment and a threedimensional cross-linked surface structure that facilitates product diffusion.

关键词： C_(sp2)-H activation V4^(+)/V5^(+)ratio Acid microenvironment Catalysis Support Catalyst activation

Theoretical analysis and experimental study on the dynamic behavior of a valve pipeline system during an earthquake

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2021年第4期20卷 969-979页

作者： Xue Ruiyuan Yu Shurong Zhang Xiheng College of petrochemical technology Lanzhou University of TechnologyLanzhou 730050China

To study the dynamic behavior of pipeline systems installed with large-mass valves within nuclear power plants during earthquakes,seismic simulation tests are carried out on a pipeline system equipped with a DN80 gate valve,and the FEM updating technique is used to identify the stiffness distribution of the *** conducting tests and a numerical analysis,the following conclusions are obtained:After a large-mass valve is installed in the pipeline,the system shows higher sensitivity to intermediate and high frequency components in the earthquake than low frequency *** is possible for the intermediate frequency components to be amplified by the valve in the horizontal direction,while the pipes tend to amplify the high frequency components in horizontal and vertical *** in the high-order modes of the system depend on valve stiffness *** the existence of a valve makes pipeline system damping distribute with an obvious non-proportional feature,when the response spectrum method is used to calculate the response of the pipeline system,it could result in an underestimation of low-damping positions and overestimation of high-damping positions.

关键词： seismic analysis shaking table test valve nuclear power plant

Identification of Parameters in 2D-FEM of Valve Piping System within NPP Utilizing Seismic Response

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2020年第10期65卷 789-805页

作者： Ruiyuan Xue Shurong Yu Xiheng Zhang College of petrochemical technology Lanzhou University of TechnologyLanzhou730050China

Nuclear power plants(NPP)contain plenty of valve piping systems(VPS’s)which are categorized into high anti-seismic *** such as seismic qualification,health monitoring and damage diagnosis of VPS’s in its design and operation processes all depend on finite element ***,in engineering practice,there is always deviations between the theoretical and the measured responses due to the inaccurate value of the structural parameters in the *** structure parameters identification of VPS within NPP is still an unexplored domain to a large *** this paper,the initial 2D-finite element model(FEM)for VPS with a DN80 gate valve was updated by utilizing seismic *** objective function used in the model updating procedure is the vibration control equation error of the *** experimental results show that the updated 2D-FEM can accurately predict the original dynamic characteristic of the *** was also found the Rayleigh damping coefficients corresponding to the VPS vary slightly with the change in seismic excitation *** research displayed the complete procedure of updating the complex structured initial FEM by utilizing seismic response,and the results show that the parameters can be accurately identified even if the seismic response used for updating merely contained the fundamental frequency information of the structure.

关键词： Seismic response nuclear power plant valve FEM updating parameter identification

Layer-by-layer Assembled Multilayers of Graphene/Mono-(6-amino-6-deoxy)-β-cyclodextrin for Detection of Dopamine

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2015年第2期33卷 185-191页

作者： Lin Tan Guo Wang Nali Chen Jianqiang Zhang Huixia Feng College of petrochemical technology Lanzhou University of TechnologyLanzhouGansu 730050China

Graphene/mono-(6-amino-6-deoxy)-β-cyclodextrin multilayer films composed of graphene sheet(GS)and mono-(6-amino-6-deoxy)-β-cyclodextrin(NH_(2)-β-CD)were fabricated easily by two ***,negatively charged graphene oxide(GO)and positively charged mono-(6-amino-6-deoxy)-β-cyclodextrin(NH_(2)-β-CD)were layer-by-layer(LBL)self-assembled on glassy carbon electrode(GCE)modified with a layer of poly(diallyldimethylammo-nium chloride)(PDDA).Then graphene/mono-(6-amino-6-deoxy)-β-cyclodextrin(GS/NH_(2)-β-CD)multilayer films were built up by electrochemical reduction of graphene oxide/mono-(6-amino-6-deoxy)-β-cyclodextrin(GO/NH_(2)-β-CD).Combining the high surface area of GS and the active recognition sites onβ-cyclodextrin(β-CD),the GS/NH_(2)-β-CD multilayer films show excellent electrochemical sensing performance for the detection of DA with an extraordinary broad linear range from 2.53 to 980.05μmol•L^(−1).This study offers a simple route to the controlla-ble formation of graphene-based electrochemical sensor for the detection of DA.

关键词： dopamine layer-by-layer graphene mono-(6-amino-6-deoxy)-β-cyclodextrin

Impregnated copper on magnetite as catalyst for the O-arylation of phenols with aryl halides

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2014年第1期25卷 141-145页

作者： Ying-Peng Zhang Ai-Hong Shi Yun-Shang Yang Chun-Lei Li School of petrochemical Engineering Lanzhou University of Technology

Nanoparticle Fe304 encapsulated CuO, as a heterogeneous catalyst, is a facile system for the synthesis of diaryl ethers by the cross-coupling reaction of various substituted aryl halides with various substituted phenols, which avoids using any type of expensive ligand and can be recovered from the reaction mixture by using a simple magnet. Moreover, this catalyst can be reused three times with high catalytic activity.

关键词： CuO-Fe3O4 Ullmann cross-coupling reaction Diaryl ether O-ArylationHeterogeneous catalysis

TRIGONOMETRIC CURVE MODIFICATION OF SCROLL PROFILE AND ITS EFFECT ON PERFORMANCES OF A SCROLL COMPRESSOR

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2005年第4期18卷 498-503页

作者： Liu Tao Liu Zhenquan College of Mechano-Electronic Engineering Lanzhou University of Technology Lanzhou 730050 China College of petrochemical technology Lanzhou University of Technology Lanzhou 730050 China

A modification of central profile with trigonometric curve is proposed based on the theory of engagement of scroll compressor. General modification equations for central profile of a pair of scrolls are given and various modification patterns are discussed. The equidistant method is employed to calculate the volume of a sealed chamber and a set of general equations is represented. Modification parameters affecting geometric and dynamic property of a scroll compressor are analyzed systematically, and the relations between them are accurately determined. The condition for transforming a trigonometric curve modification into an arc-curve modification is explained. The conclusions can also be applied to other scroll fluid machines.

关键词： Scroll profile Modification Trigonometric curve Geometric Dynamic

Numerical Simulation of Wet Particles Motion in a Vertical Powder Dryer

在线全文

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2024年第8期20卷 1823-1846页

作者： Long Yu Dongdong Pang Minmin She Hongwei Qiu Ping Cao Xiongwei You School of petrochemical Engineering Lanzhou University of TechnologyLanzhou730050China

In this study,the motion of wet particles in the drying unit of a vertical powder dryer is investigated by using a Discrete element method(DEM)coupled with a liquid bridge *** particular,by varying parameters such as the particle mass flow rates,the superficial gas velocities,and superficial gas temperatures,the influence of the moisture content on the flow behavior is *** results show that when the moisture content increases,the mean particle velocity decreases while the bed mean solid“holdup”and the mean residence time(MRT)of particles *** is also found that the local solid holdup is relatively higher in the near-wall region and decreases towards the near-fluid *** regression models are introduced accordingly for the mean particle velocity and the bed mean solid holdup by means of the RSM-BBD(Response surface methodology-Box-Behnken design)method to obtain the optimal combination of parameters for flooding ***,the optimal results are compared with numerical *** the relative error is less than 10%,this demonstrates that the proposed methodology can accurately describe the particle flow dynamics in the drying unit.

关键词： Counter-current gas-solid flow moisture content flow characteristics RSM-BBD

RuO_(2)-PdO nanowire networks with rich interfaces and defects supported on carbon toward the efficient alkaline hydrogen oxidation reaction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2023年第8期83卷 255-263,I0008页

作者： Yuanyuan Cong Fanchao Meng Haibin Wang Di Dou Qiuping Zhao Chunlei Li Ningshuang Zhang Junying Tian School of petrochemical technology Lanzhou University of TechnologyLanzhou 730050GansuChina Key Laboratory of Low Carbon Energy and Chemical Engineering of Gansu Province Lanzhou University of TechnologyLanzhou 730050GansuChina

Interfacial engineering is a promising approach for enhancing electrochemical performance,but rich and efficient interfacial active sites remain a challenge in ***,RuO_(2)-PdO heterostructure nanowire networks(NWs) with rich interfaces and defects supported on carbon(RuO_(2)-PdO NWs/C) for alkaline hydrogen oxidation reaction(HOR) was formed by a seed induction-oriented attachment-thermal treatment method for the first *** expected,the RuO_(2)-PdO NWs/C(72.8% Ru atomic content in metal) exhibits an excellent activity in alkaline HOR with a mass specific exchange current density(jo,m) of 1061 A gRuPd-1,which is 3.1 times of commercial Pt/C and better than most of the reported nonPt noble metal HOR *** at the high potential(~0.5 V ***) or the presence of CO(5 vol%),the RuO_(2)-PdO NWs/C still effectively catalyzes the alkaline ***/electrochemical analysis and theoretical calculations reveal that the interfaces between RuO_(2) and PdO act as the active *** electronic interactions between the two species and the rich defects for the interfacial active sites weaken the adsorption of Had,also strengthen the adsorption of OHad,and accelerate the alkaline HOR ***,OHadon RuO_(2) can spillover to the interfaces,keeping the RuO_(2)-PdO NWs/C with the stable current density at higher potential and high resistance to CO poisoning.

关键词： Hydrogen oxidation reaction Heterostructure Nanowire networks Defects Interfacial active sites

Novel Approach for the Decoration of Magnetic Carbon Nanospheres with Platinum Nanoparticles and Their Enhanced Peroxidase Activity for the Colorimetric Detection of H2O2

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2019年第1期35卷 163-170页

作者： SU Ce BAI Lingling ZHANG Hongbo CHANG Kaishan LI Guanbin LI Siliang School of petrochemical Engineering Lanzhou University of TechnologyLanzhou 730050P.R.China

Pt/Fe3O4-DIB-DETA-CNS(PFDDC)nanocomposite(DIB=2,4-dihydroxybenzaldehyde;DETA=diethylenetfiamine;CNS=carbon nanosphere)was synthesized by dispersing Pt nanoparticles on magnetic carbon nanospheres. The structure,morphology and composition of the nanocomposite were studied by X-ray diffraction(XRD),transmission electron microscopy(TEM),energy-dispersive X-ray spectroscopy(EDX)and X-ray photoelectron spectroscopy(XPS). In addition,the nanocomposite showed superior peroxidase-like activity towards 3,3',5,5'-tetramethylbenzidine(TMB) with a visual color change in the presence of hydrogen peroxide(H2O2).Therefore,the PFDDC nanocomposite provides a sensing platform for the colorimetric detection of H2O2 with high sensitivity and ***,the nanocomposite can be conveniently preserved and *** features enable the nanocomposite to colorimetrically detect H2O2 for potential pharmaceutical,environmental and industrial applications.

关键词： Pt nanoparticle Magnetic carbon nanosphere Peroxidase-like activity Colorimetric sensor H2O2

CRYSTALLIZATION BEHAVIOR, THERMAL AND MECHANICAL PROPERTIES OF PHBV/GRAPHENE NANOSHEET COMPOSITES

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2013年第4期31卷 670-678页

作者： Bing-jie Wang Yu-jie Zhang Jian-qiang Zhang Qu-ting Gou Zong-bao Wang Peng Chen 顾群 Ningbo Institute of Material technology and Engineering Chinese Academy of Sciences School of petrochemical technology Lanzhou University of Technology

Biodegradable poly（3-hydroxybutyrate-co-3-hydroxyvalerate）（PHBV）/graphene nanosheet （GNS） composites were prepared via a solution-casting method at low GNS loadings in this work. Transmission electron microscopy revealed that a fine dispersion of GNSs was achieved in the PHBV matrix. The thermal properties of the nanocomposites were investigated by thermogravimetric analysis, and the results showed that the thermal stability of PHBV was significantly improved with a very low loading of GNSs. Nonisothermal melts crystallization behavior, spherulitic morphology and crystal structure of neat PHBV and the PHBV/GNSs nanocomposites were investigated, and the experimental results indicated that crystallization behavior of PHBV was enhanced by the presence of GNSs due to the heterogeneous nucleation effect; however, the two-dimensional （2D） GNSs might restrict the mobility of the PHBV chains in the process of crystal growing. Dynamic mechanical analysis studies showed that the storage modulus of the PHBV/GNSs nanocomposites was greatly improved.

关键词： PHBV Graphene nanosheets Nanocomposites Solution-casting films.