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Unorthodox chemistry for an unorthodox challenge:Exploration of new chemical reactivities for a sustainable future

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Science China Chemistry 2011年第12期54卷 1815-1830页

作者： li Chao-Jun Department of Chemistry and FQRNT Center for Green Chemistry and Catalysis McGill University 801 Sherbrooke Street West Montreal QC H3A 2K6 Canada

The sustainable development of our future represents an unorthodox challenge in sciences and *** exploration of unconventional chemical reactivities that could potentially result in more sustainable chemical productions with efficient utilization of resource and inherent prevention of waste will provide the foundation for the synthetic chemistry of our *** part of this endeavor,we have explored metal-mediated reactions in water to minimize protection-deprotection and the use of organic solvents,catalytic nucleophilic additions via C-H reactions to avoid generation and use of stoichiometric organic halides and metal in water,and Cross-Dehydrogenative-Coupling(CDC) reactions to minimize overall transformation steps.

关键词： green chemistry organometallic reactions in water aldehyde-alkyne-amine coupling cross-dehydrogenative-coupling

Functional Variable Separation for Extended Nonlinear Elliptic Equations

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Communications in Theoretical Physics 2007年第3X期48卷 385-390页

作者： ZHANG Shun-li Center for Nonlinear Studies Department of Mathematics Northwest University Xi'an 710069 China Center of Nonlinear Science Ningbo University Ningbo 315211 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

This paper is devoted to the study of functional variable separation for extended nonlinear elliptic equations. By applying the functional variable separation approach to extended nonlinear elliptic equations via the generalized conditional symmetry, we obtain complete classification of those equations which admit functional separable solutions （FSSs） and construct some exact FSSs to the resulting equations.

关键词： nonlinear elliptic equation functional variable separation generalized conditional symmetry

Hydrothermal Synthesis,Crystal Structure and Electrochemical Properties of the Copper(II) Complex [Cu_4O_4(phen)_4(ClC_6H_4COO)_2(H_2O)_2]·(H_2O)_3

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1331-1336页

作者： li Wei li Chang-Hong YANG Ying-Qun KUANG Yun-Fei Department of Chemistry and Materials Science Hengyang Normal University Hengyang 421008 China Department of Chemical Engineering Hunan Institute of Technology Hengyang 421008 China

The title complex of copper（Ⅱ） with m-chlorobenzoic acid, 1,10-phenanthroline （phen） and copper perchlorate has been synthesized and characterized in the solvent mixture of water and methanol. Crystal data for this complex： triclinic, space group PI^-, a = 1.06853（12）, b = 1.30740（16）, c = 1.49546（17） nm, α= 101.791（2）,β = 103.413（2）, γ = 105.815（2）°, V= 1.8736（4） nm^3, Mr = 904.67, Dc = 1.604 g/cm^3, Z = 2,/7（000） = 924,μ = 1.34 mm^-1, GOOF = 1.049, the final R = 0.0324 and wR = 0.0797. The structure analysis shows that a chair-like structure [Cu4O4] is defined by three quadrilaterals shaped by four copper and four oxygen atoms, and every copper ion is coordinated by three oxygen atoms from three wate： molecules and two nitrogen atoms from one 1,10-phenanthroline molecule, giving a distorted square-pyramidal coordination geometry. The CV analysis results indicate that the electron transfer in the electrode reaction is quasi-reversible.

关键词： copper(Ⅱ) complex hydrothermal synthesis electrochemical property

Understanding and optimizing the gasification of biomass waste with machine learning

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Green Chemical Engineering 2023年第1期4卷 123-133,F0004页

作者： Jie li Lanyu li Yen Wah Tong Xiaonan Wang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore117585Singapore Department of Chemical Engineering Tsinghua UniversityBeijing100084China

Gasification is a sustainable approach for biomass waste treatment with simultaneous combustible H2-syngas ***,this thermochemical process was quite complicated with multi-phase products *** product distribution and composition also highly depend on the feedstock information and gasification *** present,it is still challenging to fully understand and optimize this *** this context,four datadriven machine learning(ML)methods were applied to model the biomass waste gasification process for product prediction and process interpretation and *** results indicated that the Gradient Boosting Regression(GBR)model showed good performance for predicting three-phase products and syngas compositions with test R^(2)of 0.82–*** GBR model-based interpretation suggested that both feed and gasification condition(including the contents of feedstock ash,carbon,nitrogen,oxygen,and gasification temperature)were important factors influencing the distribution of char,tar,and ***,it was found that a feedstock with higher carbon(>48%),lower nitrogen(<0.5%),and ash(1%–5%)contents under a temperature over 800℃could achieve a higher yield of H_(2)-rich *** was shown that the optimal conditions suggested by the model could achieve an output containing 60%–62%syngas and achieve an H_(2)yield of 44.34 mol/*** valuable insights provided from the model-based interpretation could aid the understanding and optimization of biomass gasification to guide the production of H_(2)-rich syngas.

关键词： Biomass to energy Gasification Data-driven Hydrogen Tar reduction

Direct writing of silver microfiber with precise control on patterning for robust and flexible ultrahigh-performance transparent conductor

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Journal of Materials Science & Technology 2020年第12期47卷 103-112页

作者： Tao Chen Heping li Jing li Sanyuan Hu Pin Ye Youwei Yan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Ultrafine silver fiber is an alternative to commercial indium tin oxide(ITO) as a new-generation flexible transparent conductor that can be used in flexible ***,its primary limitation is the unrepeatable optoelectronic properties due to the disordered distribution of silver *** this work,we report the in-situ direct writing of the silver microfiber pattern with high conductivity and transparency to attain a flexible transparent *** silver network is composed of silver microfibers,which can be artificially designed and regularly patterned under the precise control of the fiber position and shape;this is crucial for regulating its optoelectronic ***,a high-performance conductor is achieved in the silver network with high *** novel conductor has a sheet resistance of 2 Ω sq-1at 90% transparency,which corre sponds to a high Figure of merit σdc/σopt=*** in-situ direct writing technique developed here is distinct from other fabrication methods because it requires no transfer steps,templates or ***,this silver network is integrated into a light-printable rewritable device,and can be used as a wearable heater;this heater when driven by a 1.5 V battery attains a temperature of up to 55.6℃.Therefore,in-situ direct writing is expected to offer a new platform for facile,scalable,and ultralow-cost production of high-performance metal networks for flexible transparent conductors.

关键词： Silver Transparent conductor Direct writing Patterning Transparent heater

In situ investigation on densification mechanism of Ti-20Al-19Nb(at.%)alloy by TiH_(2)-assisted pressureless sintering

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Journal of Materials Science & Technology 2023年第34期165卷 170-186页

作者： Qi Cai Qilin Yu Xinyao li Yao Lu Yanmo li Ganggang Cui School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Welding Engineering and Laser Processing Centre Cranfield UniversityBedfordshireMK43 OALUK Luoyang Ship Material Research Institute Luoyang 471023China

Dense Ti-20Al-19Nb(at.%)alloys can be cost-effectively fabricated by TiH_(2)-assisted pressureless sintering;nevertheless,the densification mechanism remains controversial without understanding the entire sintering *** in situ observing the surface morphology of the Ti/Al/Nb and Ti/TiH_(2)/Al/Nb compacts upon heating,the densification mechanism of the Ti-20Al-19Nb alloys was elucidated in this *** addition to the reported reason that the dehydrogenation of TiH_(2)provided reactive Ti,the densification of Ti-20Al-19Nb alloy was found to be strongly associated with the phase transformations upon *** TiH_(2)participated in the reverse eutectoid transformation,α-Ti+δ-TiH_(2)→β-Ti,inducing theα/βand TiH_(2)/βgrain boundaries for the rapid diffusion of *** reaction of Ti(s)+Al(s)→TiAl_(3)(s)was then accelerated,and the majority of the Al phase was consumed in the solid state,which significantly reduced the pores from the transient liquid *** activation energy of the Ti-Al reaction decreased with the addition of TiH_(2),and the growth mode of the TiAl_(3)phase was *** removing the large pores at 700℃,the Ti-Al intermetallic phases were well connected,forming the continuous interdiffusion route for Ti,Al,and *** diffusion of Nb,as well as the phase transformation ofα2→B2,was then promoted,and the ripening time for the B2 phase was *** a result,the density and mechanical properties were *** initial results of this study provided a foundation for the cost-effective fabrication of high-strength Ti-Al alloys containing refractory elements.

关键词： Ti-Al-Nb alloy Sintering mechanism Porosity In situ observation Phase transformation

Shear behaviour of a rock bridge sandwiched between incipient joints under the influence of hydraulic pressures

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International Journal of Mining Science and Technology 2023年第2期33卷 233-242页

作者： Shicheng Wang Xuxu Yang lichao li Panpan Sun Lei Yang Fuwei li Shandong Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science and TechnologyQingdao 266590China School of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China

The rock bridges sandwiched in incipiently jointed rock mass were considered as barriers that block the fluid seepage,and provide certain shear strength *** better revealing the influence of hydraulic pressure on the failure behaviour of rock bridges,direct shear tests were carried out through a newly proposed method on rock samples that contain two parallel incipient *** developing the gypsum-silicone pad coupling samples,a conventional triaxial test system was qualified to implement direct shear tests with satisfied sealing *** results showed that the rock bridges could be failed through the tensile failure,shear failure and mixed failure *** hydraulic pressure would facilitate the tensile failure mechanism and induce rougher fracture surfaces;while the normal stress would facilitate the shear failure mechanism and induce less rough *** hydraulic pressure reduced the global shear strength of the rock block through reducing the efficient normal stress applied on the rock bridge area,which was highly dependent on the joint persistence,***,because of the iterating occurrence of the hydraulic pressure lag with the fracture propagation,the rock bridge failure stage in the shear stress-shear displacement curves displayed a fluctuation trend.

关键词： Direct shear tests Hydraulic pressure Rock bridge Failure mechanism Hydraulic pressure lag Rock joints

Theoretical and Experimental Study of A Coaxial Double-Buoy Wave Energy Converter

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China Ocean Engineering 2021年第3期35卷 454-464页

作者： li De-min DONG Xiao-chen SHI Hong-da li Yan-ni Department of Ocean Engineering College of EngineeringOcean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China Qingdao Municipal Key Laboratory of Ocean Renewable Energy Ocean University of ChinaQingdao 266100China Pilot National Laboratory for Marine Science and Technology(QingDao) Qingdao 266200China

The double-body heave wave energy converter(WEC)is one of the most conducive devices to absorb the wave energy from relative motion while the law of which is not well *** paper makes an in-depth study on this wave energy converter,by means of the combination of theoretical analysis and physical model *** hydrodynamic characteristics and energy capture of the double-buoy under constant and linear Power Take-Off(PTO)damping are *** of absolute mass and mass ratio are discussed in the theoretical *** displacement amplitude and average power output are tested in the experiment to analyze the effect of the wave period and outer buoy’s mass,while the capture width ratio(CWR)is also *** show that the wave period and mass of the buoys have a significant effect on the *** forms of PTO damping have no influence on the optimal wave period and mass ratio of this *** is recommended to select the double-buoy converter with a mass ratio of 0.80 and to place it in an area with the frequent wave period close to the natural period of the outer buoy to achieve the optimal energy capture.

关键词： coaxial double-buoy wave energy converter hydrodynamic characteristics model test power take-off

Formation mechanism of typical aromatic sulfuric anhydrides and their potential role in atmospheric nucleation process

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Journal of Environmental Sciences 2023年第1期123卷 54-64页

作者： Haijie Zhang Rui Gao Hong li Yunfeng li Yisheng Xu Fahe Chai State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

Sulfuric anhydrides,generated from the cycloaddition reaction of SO3with carboxylic acids,have been revealed to be potential participants in the nucleation process of new particle formation(NPF).Hence the reaction mechanisms of typical aromatic acids(benzoic acid(BA),phenylacetic acid(PAA),phthalic acid(PA),isophthalic acid(mPA),and terephthalic acid(PTA))with SO3to generate the corresponding aromatic sulfuric anhydrides were investigated by density functional theory calculations at the level of M06-2X/6-311++G(3df,3pd).As a result,these reactions were found to be feasible in the gas phase with barriers of 0.34,0.30,0.18,0.08 and 0.12 kcal/mol to generate corresponding aromatic sulfuric anhydrides,*** thermodynamic stabilities of clusters containing aromatic sulfuric anhydrides and atmospheric nucleation precursors(sulfuric acid,ammonia and dimethylamine)were further analyzed to identify the potential role of aromatic sulfuric anhydrides in *** the thermodynamic stability of a cluster depends on both the number and strength of hydrogen bonds,the greater stability of the interactions between atmospheric nucleation precursors and aromatic sulfuric anhydrides than with aromatic acids make aromatic sulfuric anhydrides potential participators in the nucleation process of ***,compared with BA,the addition of a-CH_(2)-functional group in PAA has little influence on the reaction barrier with SO3but an inhibitive effect on the thermodynamic stability of *** position of the two-COOH functional groups in PA,m PA and PTA does not have a consistent impact on the reaction barrier with SO3or the thermodynamic stability.

关键词： New particle formation(NPF) Sulfuric anhydride Reaction mechanism Atmospheric clusters Thermodynamic stability