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Influences of polymorphism of packed particles on bulk characterizations in fluidization realm

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Chinese Journal of Chemical Engineering 2024年第10期74卷 238-248页

作者： Quanhong Zhu Yalong cao Qiang Zhang Wankun Liu Hao Guan Donghui Liu Hengjun Gai College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China School of Chemical and Environmental Engineering China University of Mining and Technology-BeijingBeijing 100083China

The characterization of a particle ensemble(rather than a single particle) is of paramount significance to various particle technologies and has long been a fundamental subject in the fluidization realm. However, many of such bulk characterizations as loosely-packed density(ρbl), minimum fluidization velocity(Umf), sphericity(φ), discharge rate through orifice(q), angle of repose(β), and segregation index(S),were found to be poorly reproducible, making the reported results seldom comparable. Since these bulk characterizations started from the packed state of particles, such poor reproducibility was ascribed to the polymorphism of packed particles in this work. We observed that in the fluidized bed, the settled/packed state of particles varied monotonously with the settling rate(a) from complete fluidization to zero. This phenomenon confirmed the polymorphic characteristic of packed particles and further enabled us to systematically disclose/clarify its influences on the aforementioned bulk characterizations. Such influences could be comprehensively and intuitively reflected by the impacts induced by a. With the decrease of a, ρbl, φ and q first increased, then decreased, and finally leveled off while Umfand β showed an opposite trend. On the other hand, S first increased and then remained invariant. As per these findings and definitions of these bulk characterizations, benchmarks were indicated to unify the selection of settled state among future scholars and further make their outcomes become fairly comparable. Additionally, most packed states of the particle ensemble were proved to be metastable with their formation and behavior being identical to those of the amorphous state.

关键词： Fluidization Fluidized-bed Particle Polymorphism Bulk characterization Comparability

Deformation behavior and fluid action of quartz veins in the Xuelongshan metamorphic complex,Western Yunnan

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Science China Earth Sciences 2023年第9期66卷 2011-2033页

作者： Shuting WANG Shuyun cao Lefan ZHAN Xuemei CHENG Yanlong DONG Xiaowen LI Wenyuan LI State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China

The Xuelongshan metamorphic complex underwent Cenozoic sinistral strike-slip shearing and exhumation from deep to shallow in the southeast margin of the Tibet *** studied the deformation behavior and fluid action of quartz veins in the metamorphic complex in depth based on macroscopic observation,electron backscatter diffraction fabric,and fluid inclusion *** mylonitic samples are characterized by strongly elongated and orientated porphyroclasts and a finegrained matrix with a shear strain of *** ultramylonitic samples are characterized by a strongly fine-grained matrix with a shear strain of ***{m}glide controls the quartz deformation in the mylonites and *** the dominant recovery mechanism,subgrain rotation dynamic recrystallization reduces the grain size and promotes rheological *** porphyroclasts restrict the crystal orientation of the recrystallized quartz *** mylonitic quartz veins have abundant single-phase and two-phase fluid ***,the ultramylonitic quartz veins have a few fluid inclusions,most of which are small and irregular toward the grain *** temperature and pressure of fluid activity in quartz veins are 550–500℃and 391–218 MPa for ultramylonitic quartz veins,with a depth of 14.2–7.9 km and 450–400℃and 236–91 MPa for mylonitic quartz veins,with a depth of 8.6–3.3 *** deformation process changes the shape of fluid inclusions from mylonitization to ultramylonitization and causes fluid leakage,an increase in local fluid pressure at the boundary,and hydrolysis weakening,promoting lattice dislocation glide and recrystallization,which is directly related to regional continuous shear deformation and exhumation.

关键词： Deformed quartz veins EBSD fabric Fluid Rheological weakening Exhumation process

Experimental research and numerical simulation of the multi-field performance of cemented paste backfill:Review and future perspectives

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International Journal of Minerals,Metallurgy and Materials 2023年第2期30卷 193-208页

作者： Yong Wang Zhenqi Wang Aixiang Wu Liang Wang Qing Na Chen cao Gangfeng Yang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining&Technology(Beijing)Beijing 100083China ZHONGGUANCUN Green Mine Industry Alliance Beijing 100083China

Cemented paste backfill(CPB)technology is a green mining method used to control underground goaves and tailings *** curing process of CPB in the stope is the product of a thermo-hydro-mechanical-chemical multi-field performance *** present,research on the multi-field performance of CPB mainly includes indoor similar simulation experiments,in-situ multi-field performance monitoring experiments,multi-field performance coupling model construction of CPB,and numerical simulation of the multi-field performance of *** it is hard to study the in-situ multi-field performance of CPB in the real stope,most current research on in-situ multi-field performance adopts the numerical simulation *** simulating the conditions of CPB in the real stope(e.g.,maintenance environment,stope geometry,drainage conditions,and barricade and backfilling rates),the multi-field performance of CPB is further *** paper summarizes the mathematical models employed in the numerical simulation and lists the engineering application cases of numerical simulation in the in-situ multi-field performance of ***,it proposes that the multi-field performance of CPB needs to strengthen the theoretical study of multi-field performance,form the strength design criterion based on the multi-field performance of CPB,perform a full-range numerical simulation of the multi-field performance of CPB,develop a pre-warning technology for the CPB safety of CPB,develop automatic and wireless sensors for the multi-field performance monitoring of CPB,and realize the application and popularization of CPB monitoring technology.

关键词： cemented paste backfill multi-field performance in situ mathematic model numerical simulation

Self-doped n-type small molecular electron transport materials for high-performance organic solar cells

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Science China Chemistry 2017年第8期60卷 1136-1144页

作者： jinju liu nannan zheng zhicheng hu zhenfeng wang xiye yang fei huang yong cao Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of Technology Guangzhou 510640 China

Two naphthalene diimide （NDI） and perylene diimide （PDI） based n-type water/alcohol soluble small molecules （NFN and PFP） are designed and utilized as electron transport layers （ETLs） for organic solar cells （OSCs）. NFN and PFP are synthesized by using Sonogashira coupling from alkynyl modified fluorene with mono-bromo substituted NDI and PDI. Density functional theory study results of NFN and PFP show that they possess excellent planarity due to the employment of triple bonds as connection units. Moreover, it was shown by electron paramagnetic resonance study that both NFN and PFP possess obvious self-doping behaviors, which may effectively enhance their charge transporting capability as ETLs in OSCs. Power conversion efficiencies of 8.59% and 9.80% can be achieved for OSCs with NFN and PFP as ETLs, respectively. The higher power conversion efficiency （PCE） of PFP based photovoltaic device is originated from the stronger doping property and higher mobility of PFR

关键词： self-doped n-type small molecules organic solar cells electron transport layers

Degradation of ofloxacin using peroxymonosulfate activated by nitrogen-rich graphitized carbon microspheres:Structure and performance controllable study

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Journal of Environmental Sciences 2021年第1期33卷 10-20页

作者： Changsheng Feng Chen Chen Yu Zhu Qi cao Chao Chen Caiyun Jiang Yuping Wang School of Chemistry and Material Science Jiangsu Provincial Key Laboratory of Materials cycling and Pollution ControlNanjing Normal UniversityNanjing 210046China Department of Engineering and Technology Jiangsu lnstitute of CommerceNanjing 211168China

Nitrogen-rich graphitized carbon microspheres(NGCs)with hierarchically porous were constructed by *** different heat treatment conditions,the structure,morphology and properties of NGCs were studied by using multiple characterization *** results showed that the chemical microenvironments(*** chemistry,degree of graphitization and defective,etc.)and microstructures properties(***,specific surface area,particle size,etc.)could be delicately controlled via thermal carbonization *** degradation of ofloxacin(OFLX)by NGCs activated peroxymonosulfate(PMS)was studied *** was found that the synergistic coupling effect between optimum N or O bonding species configuration ratio(graphitic N and C=O)and special microstructure was the main reason for the enhanced catalytic activity of NGC-800(calcination temperature at 800°C).Electron paramagnetic resonance(EPR)experiments and radical quenching experiments indicated that the hydroxyl(·OH),sulfate(SO4^·-)and singlet oxygen(^1O_(2))were contributors in the NGC-800/PMS *** investigation of the durability of chemical structures and surface active sites revealed that undergo N bonding species configuration reconstruction and cannibalistic oxidation during PMS activation *** used NGC-800 physicochemical properties could be recovered by heat treatment to achieve the ideal catalytic *** findings proposed a valuable insight for catalytic performance and controllable design of construction.

关键词： Peroxymonosulfate Ofloxacin degradation Carbonization temperature Carbocatalyst

Effect of multiphase content on temperature-dependent electrical conductivity in silicone rubber composites

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High Voltage 2023年第2期8卷 283-292页

作者： ying Lin Yuhao Liu Bin cao Jianyi Xue Liming Wang Jianing Wang Lijian Ding School of Electrical and Automation Engineering Hefei University of TechnologyHefeiChina Institute of Energy Hefei Comprehensive National Science CenterHefeiChina Laboratory of Advanced Technology of Electrical Engineering and Energy Graduate School at ShenzhenTsinghua UniversityShenzhenGuangdongChina

To investigate how the multiphase structures affect the electrical conductivity in semicrystalline polymer composites,herein,an accurate multiphase content calculation method is proposed and verified,which combines amorphous phase information in broadband dielectric spectroscopy and crystalline phase information in differential scanning *** aluminium hydroxide(ATH)filled silicone rubber as an example,it is found that the rigid amorphous fraction(RAF)corresponding to the chains constrained by crystals(RAF_(cry))is not linearly increased with crystalline fraction(CF).Compared to non-isothermal crystallisation,RAF caused by ATH/silicone rubber interface(RAF_(int))after isothermal crystallisation at 213 K changes little,while mobile amorphous fraction and RAFcry is attenuated and CF is *** on the calculated structures of ATH filled silicone rubber,activation energy of conductivities during cooling is dominated by the thermal transition for conductive ions and shortened distance among the conductive ions through shrunk volumes of the amorphous *** findings deepen the understanding of multiphase content in semi-crystalline polymer composites and its relationship with electrical conductivity,which can be applied in manipulating electrical performance of semi-crystalline polymers by fillers.

关键词： composites rubber electrical

Solar radiation effects on leaf nitrogen and phosphorus stoichiometry of Chinese fir across subtropical China

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Forest Ecosystems 2021年第4期8卷 831-840页

作者： Ran Tong yini cao Zhihong Zhu Chenyang Lou Benzhi Zhou Tonggui Wu Qianjiangyuan Forest Ecosystem Research Station Research Institute of Subtropical ForestryChinese Academy of ForestryHangzhou 311400China East China Coastal Forest Ecosystem Long-term Research Station Research Institute of Subtropical ForestryChinese Academy of ForestryHangzhou 311400China Guangdong Provincial Key Laboratory of Water Quality 313 Improvement and Ecological Restoration for Watersheds Institute of Environmental and Ecological EngineeringGuangdong 314 University of TechnologyGuangzhou 510006China Zhejiang A&F University Hangzhou 311300China

Background:Solar radiation(SR)plays critical roles in plant physiological processes and ecosystems ***,the exploration of SR influences on the biogeochemical cycles of forest ecosystems is still in a slow progress,and has important implications for the understanding of plant adaption strategy under future environmental ***,this research was aimed to explore the influences of SR on plant nutrient characteristics,and provided theoretical basis for introducing SR into the establishment of biochemical models of forest ecosystems in the future ***:We measured leaf nitrogen(N)and phosphorus(P)stoichiometry in 19 Chinese fir plantations across subtropical China by a field *** direct and indirect effects of SR,including global radiation(Global R),direct radiation(Direct R)and diffuse radiation(Diffuse R)on the leaf N and P stoichiometry were ***:The linear regression analysis showed that leaf N concentration had no association with SR,while leaf P concentration and N:P ratio were negatively and positively related to SR,*** least squares path model(PLS-PM)demonstrated that SR(*** R and Diffuse R),as a latent variable,exhibited direct correlations with leaf N and P stoichiometry as well as the indirect correlation mediated by soil P *** direct associations(path coefficient=−0.518)were markedly greater than indirect associations(path coefficient=−0.087).The covariance-based structural equation modeling(CB-SEM)indicated that SR had direct effects on leaf P concentration(path coefficient=−0.481),and weak effects on leaf N *** high SR level elevated two temperature indexes(mean annual temperature,MAT;≥10°C annual accumulated temperature,≥10℃ AAT)and one hydrological index(mean annual evapotranspiration,MAE),but lowered the soil P ***,MAE and soil P content could affect the leaf P concentration,which cause the indirect effect of SR on leaf P concentration(pa

关键词： Solar radiation Leaf Soil Nitrogen and phosphorus Stoichiometry Chinese fir

Phosphide-oxide honeycomb-like heterostructure CoP@CoMoO4/CC for enhanced hydrogen evolution reaction in alkaline solution

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Journal of Materials Science & Technology 2020年第11期42卷 177-184页

作者： Zheng Liu Jieqiong Wang Changhong Zhan Jing Yu Yang cao Jinchun Tu Changsheng Shi State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringSchool of ScienceHainan UniversityHaikou 570228China Qiongtai Normal University Haikou 571127China

The design and construction of effective and stable hydrogen evolution reaction(HER)catalysts represent the key to obtaining hydrogen energy *** metal phosphides(TMPs)have attracted considerable attention due to their unique catalytic mechanism,which is similar to ***,single-phase TMPs remain limited by their low activity and weak stability in alkaline *** this work,CoP@CoMoO4 nanosheets with phosphide and oxide heterostructure were synthesized on carbon cloth(CC)through hydrothermal method and subsequently reacted with red phosphorus in a tube *** outstanding synergy between CoP and CoMoO4 enhanced the HER activity and stability in alkaline *** CoP@CoMoO4/CC heterostructure exhibited excellent HER activity with a low overpotential of 89 mV at 10 mA cm^-2 with Tafel slope of 69 mV dec^-1,and outstanding stability when compared with single-phase *** present research provides a new approach for the preparation of inexpensive,highly active,and highly durable phosphorus-based catalyst for HER.

关键词： Phosphorus-oxide Heterostructure Stability Hydrogen evolution reaction

Molecular Engineering of g-C_(3)N_(4)with Dibenzothiophene Groups as Electron Donor for Enhanced Photocatalytic H_(2)-Production

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Chinese Journal of Structural Chemistry 2022年第6期41卷 48-54页

作者： Shanren Tao Sijie Wan Qinyang Huang Chengming Li Jiaguo Yu Shaowen cao State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

The construction of donor-acceptor(D-A)molecular structure is an attractive strategy to enhance the photocatalytic performance of polymeric ***,dibenzothiophene(DBT)-4-carbaldehyde as the precursor is introduced into g-C_(3)N_(4)(TCN)prepared by two-step thermal polymerization to construct an intramolecular D-A type copolymer(TCN-DBT_(x)).DFT calculation and experimental results reveal that DBT plays the role of electron donor unit to modify g-C_(3)N_(4).The incorporation of DBT not only adjusts the band gap to improve reduction ability,but also induces an internal electric field with extendingπ-conjugated system for effective charge *** a result,TCN-DBT_(x)exhibits much better photocatalytic performance with an optimal hydrogen production rate of 3334μmol h^(-1)g^(-1),which is 2.5 times that of *** work provides a protocol for preparing high-performance g-C_(3)N_(4)-based photocatalysts toward various applications.

关键词： carbon nitride donor-acceptor photocatalysis charge transfer

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