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Particuology 2023年第12期83卷 194-211页

作者： Hai Qu jun Hong Ying Liu Zhijun Zeng Xu Liu Xiangjun Chen Ruichang guo Chongqing University of Science and Technology Chongqing401331China Department of mining and minerals Engineering Virginia TechBlacksburgVA24061USA

Slurry flow and proppant placement in irregular fractures are crucial to evaluate hydraulic fracturing stimulation but need to be better *** study aims to investigate how irregular fracture affects proppant transport and distribution using laboratory experiments and micro-scale numerical *** unresolved method of the computational fluid dynamics(CFD)and the discrete element method(DEm)considers Saffman lift force,magnus force,and virtual mass force to accurately capture the frequent interaction between proppant and *** results validated the reliability of the optimized CFD-DEm model and calibrated primary *** effects of crack height and width,bending angle,and distance between the crack and inlet on particle distribution were *** results indicated that the improved numerical method could rationally simulate proppant transport in fractures at a scale *** small crack height causes downward and upward flows,which wash proppant to the fracture rear and form isolated proppant dunes.A wider region in the fracture is beneficial to build up a large dune,and the high dune can hinder particle transport into the fracture *** the crack is close to the inlet,the primary fracture without proppants will close to hinder gas *** smaller the bending angle,the smaller the proppant dune.A regression model can precisely predict the dune coverage *** results fundamentally understand how complex fractures and natural cracks affect slurry flow and proppant distribution.

关键词： Slurry flow Sand transport Particle-fluid interaction Irregular channel CFD-DEm

mechanical properties and thermal deformation behavior of low-cost titanium matrix composites prepared by a structure-optimized Y_(2)O_(3) crucible

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journal of Iron and Steel Research International 2024年第3期31卷 738-751页

作者： Qian Dang Gang Huang Ye Wang Chi Zhang guo-huai Liu Zhao-dong Wang The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina School of materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150004HeilongjiangChina School of materials Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina

A porous yttrium oxide crucible with both thermal shock resistance and erosion resistance was developed by structural *** structure-optimized yttrium oxide crucible was proved to be suitable for melting highly reactive titanium ***-cost(TiB+Y2O_(3))-reinforced titanium matrix composites were prepared by vacuum induction melting using the prepared *** thermal deformation behavior and microstructure evolution of(TiB+Y2O_(3))-reinforced tita-nium matrix composites were investigated at deformation temperatures of 900-1100℃with strain rates of 0.001-1 *** results showed that the prepared yttrium oxide crucible had both thermal shock and erosion resistance,the low-cost titanium matrix composites could be prepared by the developed yttrium oxide crucibles which were homogeneous in composition and highly sensitive to strain rate and deformation temperature,and the peak and theological stresses decreased with increasing deformation temperature or decreasing strain *** addition,the average thermal deformation activation energy of the composites was calculated to be 574.6 kj/mol by establishing the Arrhenius constitutive equation in consideration of the strain variables,and the fitting goodness between the predicted stress value and the measured value was 97.624%.The calculated analysis of the hot processing map showed that the best stable thermal deformation zone was located in the deformation temperature range of 1000-1100℃and strain rate range of 0.001-0.01 s^(-1),where the peak dissipation coefficient wasη=71%.In this zone,the deformation of the reinforcement and matrix was harmonious,the reinforcement was less likely to fracture,dynamic recrystallization occurred more fully and the alloy exhibited near steady rheological characteristics.

关键词： Yttrium oxide crucible Titanium matrix composite Thermal deformation behavior Constitutive equation Hot processing map microstructure evolution

Compound Control Strategy of Cuk AC/AC Converter for Street Lighting Application 36

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Compound Control Strategy of Cuk AC/AC Converter for Street ...

Highly efficient production of 2,5-dihydroxymethylfuran from biomass-derived 5-hydroxymethylfurfural over an amorphous and mesoporous zirconium phosphonate catalyst

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作者： menglong Liu Zemin Song Yuanbo guo Xiaohua Zhang School of Electrical Engineering Dalian University of Technology

ISBN: (纸本)9781538629185

By using the characteristic that the output voltage of Cuk circuit can be step-up or step-down,Cuk AC/AC converter is applied in the field of street lighting,and an illuminance controller with continuous change of output voltage is proposed in this *** at the problem of slow response speed of feedback control technology,this paper establishes the mathematical model based on the state-space average method,and puts forward a double-feedforward compound control *** the basis of theoretical analysis,the simulation based on mATLAB/Simulink is carried out,and the simulation results prove that the illuminance controller with compound control strategy has the advantages of wide output voltage range,small size,low harmonic content,high response speed and high stability,and it is a feasible strategy of energy saving technology on street lighting.

关键词： Cuk direct AC/AC converter illuminance controller compound control strategy street lighting

来源： cnki会议评论

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journal of Energy Chemistry 2019年第10期28卷 82-92页

作者： Lei Hu Ning Li Xiaoli Dai Yuqi guo Yetao jiang Aiyong He jiaxing Xu jiangsu Key Laboratory for Biomass-Based Energy and Enzyme Technology Jiangsu Collaborative Innovation Center of Regional Modern Agriculture &Environmental Protection School of Chemistry and Chemical Engineering Huaiyin Normal University

The development of high-efficiency and low-cost catalysts is very crucial for the meerweinPonndorf-Verley (mPV) reduction of biomass-derived 5-hydroxymethylfurfural (HmF) into 2,5-dihydroxymethylfuran (DHmF). In this work, an amorphous and mesoporous zirconium phosphonate catalyst (Zr-DTmP), which is a zirconium-containing organic-inorganic nanohybrid, was successfully designed and synthesized by the simple assembly of zirconium tetrachloride (ZrCl4) and diethylene triaminepenta(methylene phosphonic acid)(DTmP). Satisfactorily, when Zr-DTmP was employed for the mPV reduction of HmF in the presence of 2-butanol (secBuOH), DHmF yield could be achieved as 96.5% in 3 h under a relatively mild reaction temperature of 140℃. Systematic investigations indicated that this high catalytic activity should be mainly due to the cooperative role of enhancive Lewis acid site (Zr4+) and Lewis base site (O2-) in activating the carbonyl group of HmF and dissociating the hydroxyl group of secBuOH, respectively. Additionally, Zr-DTmP showed excellent catalytic stability, when it was successively used 5 recycles, its surface characteristics and textural properties still remained almost unchanged, and so, the catalytic activity was not obviously affected. more interestingly, Zr-DTmP could also be applied for the selective reduction of other biomass-derived carbonyl compounds, such as 5-methylfurfural (mF), furfural (FF), levulinic acid (LA), ethyl levulinate (EL) and cyclohexanone (CHN), into the corresponding products with high yields, which is beneficial to the effective synthesis of various valuable bio-based chemicals.

关键词： 5-Hydroxymethylfurfural 2,5-Dihydroxymethylfuran 2-Butanol Zirconium phosphonate catalyst meerwein-Ponndorf-Verley reduction

Heat treatment bimetallic PdAu nanocatalyst for oxygen reduction reaction

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journal of Energy Chemistry 2020年第1期29卷 217-223,I0008页

作者： Qingyun Hu Wei Zhan Yifei guo Laiming Luo Ronghua Zhang Di Chen Xinwen Zhou College of Biological and Pharmaceutical Science China Three Gorges University

Pd-based nanocatalyst is a potential oxygen reduction oxidation(ORR)catalyst because of its high activity in alkaline medium and low *** this work,bimetallic Pd Au nanocatalysts are prepared by one-pot hydrothermal method using triblock pluronic copolymers,poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)(PEO19-PPO69-PEO19)(P123)as reducer and stabilizer,and heat-treatment method is applied to regulate catalyst structure and improve catalyst *** results show that the heat treatment can agglomerate the catalyst to a certain extent,but effectively improve the crystallinity and alloying degree of the *** ORR performance of the Pd Au nanocatalysts obtained under different heat treatment conditions is systematically *** with commercial Pd black and Pd Au catalyst before heat treatment,the ORR performance of Au Pd nanocatalyst obtained after heat treatment for one hour at 500℃ has been *** Pd Au nanocatalysts after heat treatment also display enhanced anti-methanol toxicity ability in acidic medium.

关键词： PdAu catalysts Nanochain Heat treatment Oxygen reduction reaction Anti-methanol oxidation

Effect of high stirring speed on the agglomerate behaviors for cohesive SiO_(2) powders in gas fluidization

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Particuology 2023年第9期80卷 192-201页

作者： Fan Liu Zhan Du Qingshan Zhu Xiaojun guo Hebang Shi Pengpeng Lv Hongzhong Li School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of multiphase Complex Systems Institute of Process EngineeringChina Academy of SciencesBeijing100190China

The effects of superficial gas velocity and mechanical stirring speed on the precise regulation of flow regimes for cohesive SiO2 powders(mean diameter is 16μm)were experimentally investigated in a stirring-assisted fluidized *** results showed that compared with the agglomerates formed in the non-assisted fluidization of cohesive SiO2 powders,the introduction of mechanical stirring could effectively reduce the size of agglomerates and well disperse the agglomerates during *** best regulation range of agglomerate particulate fluidization can be achieved at 600 rpm when agglomerate sizes were reduced to below 200μ*** investigation based on the operational phase diagram revealed that transformations of flow regimes were dominated by both stirring speed and gas *** stirring applied enlarges the operational range of agglomerate particulate fluidization(APF)with a delayed onset of bubbling for cohesive ***,the exorbitant speed increases the collision velocity and contact area between small agglomerates,which results in the formation of unstable agglomerates and the whirlpool of powder.

关键词： Cohesive powders Stirring-assisted fluidized bed Agglomerate size Agglomerate particulate fluidization

Advances of polymer binders for silicon-based anodes in high energy density lithium-ion batteries

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Infomat 2021年第5期3卷 460-501页

作者： Yu-ming Zhao Feng-Shu Yue Shi-Cheng Li Yu Zhang Zhong-Rong Tian Quan Xu Sen Xin Yu-guo guo CAS Key Laboratory of molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of Sciences(CAS)BeijingChina Shenzhen EUBO New material Technology Co. LtdShenzhenChina University of Chinese Academy of Sciences BeijingChina

Conventional lithium-ion batteries(LIBs)with graphite anodes are approaching their theoretical limitations in energy *** the conventional graphite anodes with high-capacity Si-based anodes represents one of the most promising strategies to greatly boost the energy density of ***,the inherent huge volume expansion of Si-based materials after lithiation and the resulting series of intractable problems,such as unstable solid electrolyte interphase layer,cracking of electrode,and especially the rapid capacity degradation of cells,severely restrict the practical application of Sibased *** the past decade,numerous reports have demonstrated that polymer binders play a critical role in alleviating the volume expansion and maintaining the integrity and stable cycling of Si-based *** this review,the state-of-the-art designing of polymer binders for Si-based anodes have been systematically summarized based on their structures,including the linear,branched,crosslinked,and conjugated conductive polymer ***,the comprehensive designing of multifunctional polymer binders,by a combination of multiple structures,interactions,crosslinking chemistries,ionic or electronic conductivities,soft and hard segments,and so forth,would be promising to promote the practical application of Si-based ***,a perspective on the rational design of practical polymer binders for the large-scale application of Si-based anodes is presented.

关键词： high energy density lithium-ion battery multifunctional binder polymer binder silicon anode

The characterization of Fe-rich phases in a high-pressure die cast hypoeutectic aluminum-silicon alloy

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journal of materials Science & Technology 2020年第16期47卷 54-62页

作者： X.Y.jiao C.F.Liu Z.P.guo G.D.Tong S.L.ma Y.Bi Y.F.Zhang S.m.Xiong School of materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced materials Processing Technology Tsinghua UniversityBeijing 100084China China FAW Foundary Co. LTDChangchun 130011China

Both microstructural characteristics and fracture behavior of Fe-rich phases in a high-pressure die-cast hypoeutectic Al-Si alloy were *** was focused on the morphology and formation mechanism of Fe-rich phases,together with their influence on *** show that primary Ferich phases exhibited in blocky shape precipitated from liquid while secondary Fe-rich phase in a large net shape was distributed along eutectic boundary participating in a ternary eutectic *** synchrotron X-ray tomography characterization,three Fe-rich phases with different morphologies,i.e.,polyhedral shape,fine compact shape and Chinese script-type shape were extracted along the radial *** slow-shot speed promoted the polyhedral Fe-rich phase to precipitate in slow-shot sleeve while decreased the formation of fine compact and Chinese script-type Fe-rich phases in die *** of a worse deformation compatibility,polyhedral Fe-rich phases fractured and became stress concentration sources before the failure of the casting.

关键词： Hypoeutectic Al-10Si Fe-rich phases Fracture morphology High pressure die casting

Oxidation of diclofenac by permanganate: Kinetics, products and effect of inorganic reductants

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Chinese Chemical Letters 2023年第4期34卷 378-383页

作者： Run Huang Chaoting Guan Qin guo Zhen Wang Hanping Pan jin jiang Key Laboratory for City Cluster Environmental Safety and Green Development of the ministry of Education School of EcologyEnvironment and ResourcesGuangdong University of TechnologyGuangzhou 510006China Southern marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China

The large consumption and discharge of diclofenac(DCF) lead to its frequent detection in surface water and groundwater, posing great threats to humans and ecosystems. This study explored the oxidation kinetics of DCF by permanganate(mn(Ⅶ)), and expounded the underlying reason for the unusual p Hdependency that was unclear in previous studies. The kinetics of DCF analogues(i.e., aromatic secondary amines) by mn(Ⅶ) oxidation were comparatively investigated. Then, a tentative kinetic model involving the formation of an intermediate between mn(Ⅶ) and DCF or its analogues was proposed to fit the p H-rate profile. Since DCF contained two chloro groups, and a carboxyl group which could be ionized by negative electrospray ionization, a precursor ionization scanning approach was used for the first time for detection of N-containing chlorinated oxidation products. New degradation pathways of DCF containing ring opening, carboxylation, carbonylation, electrophilic addition, hydroxylation and dehydrogenation were proposed based on the identified oxidation products. moreover, it was demonstrated that the introduction of various reducing agents such as mn(Ⅱ), Fe(Ⅱ) and bisulfite significantly improved the oxidation kinetics of DCF by mn(Ⅶ). The positive effects of mn(Ⅱ) and Fe(Ⅱ) were mainly attributed to the accelerated formation of mnO_(2)that acted as a catalyst or co-oxidizer contributing to DCF degradation. The presence of bisulfite caused two-stage kinetics, where a sharp drop of DCF concentration followed by a slowdown of DCF removal. In the first stage, potent reactive manganese species(e.g., mn(Ⅲ), mn(V), and mn(VI)) and sulfate radical were generated during reaction of bisulfite with mn(Ⅶ), whereas bisulfite was depleted fast due to excess mn(Ⅶ) concentrations and the system became the mn(Ⅶ)/mnO_(2)system in the second stage. These results provide new insight into reaction mechanism of DCF with mn(Ⅶ)as well as propose a feasible strategy for enhancing the treatment of D

关键词： Permanganate Diclofenac Aromatic secondary amines Precursor ionization scanning Reductant activation

Software-aided detection and structural characterization of cyclic peptide metabolites in biological matrix by high-resolution mass spectrometry

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journal of Pharmaceutical Analysis 2020年第3期10卷 240-246页

作者： ming Yao Tingting Cai Eva Duchoslav Li ma Xu guo mingshe Zhu Pharmaceutical Candidate Optimization Bristol-Myers SquibbPrincetonNJUSA XenoBiotic Labs WuXi AppTecNanjingChina SCIEX ConcordONL4K 4V8Canada massDefect Technologies PrincetonNJUSA

Compared to their linear counterparts,cyclic peptides show better biological activities,such as antibacterial,immunosuppressive,and anti-tumor activities,and pharmaceutical properties due to their conformational ***,cyclic peptides could form numerous putative metabolites from potential hydrolytic cleavages and their fragments are very difficult to *** characteristics pose a great challenge when analyzing metabolites of cyclic peptides by mass *** study was to assess and apply a software-aided analytical workflow for the detection and structural characterization of cyclic peptide *** and atrial natriuretic peptide(ANP)as model cyclic peptides were incubated with trypsin/chymotrypsin and/or rat liver S9,followed by data acquisition using TripleTOF?*** full-scan mS and mS/mS datasets were automatically processed through a combination of targeted and untargeted peak finding ***/mS spectra of predicted metabolites were interrogated against putative metabolite sequences,in light of a,b,y and internal fragment *** resulting fragment assignments led to the confirmation and ranking of the metabolite sequences and identification of metabolic *** a result,29 metabolites with linear or cyclic structures were detected in the insulin incubation with the hydrolytic *** of twenty insulin metabolites were further determined,which were consistent with the hydrolytic sites of these *** the same manner,multiple metabolites of insulin and ANP formed in rat liver S9 incubation were detected and structurally characterized,some of which have not been previously *** results demonstrated the utility of software-aided data processing tool in detection and identification of cyclic peptide metabolites.

关键词： Atrial natriuretic peptide metabolism of cyclic peptide High resolution mass spectrometry Insulin Software-aided data processing