检索结果-南通市图书馆

Recent Advances in the Catalytic Upgrading of Biomass Platform Chemicals Via Hydrotalcite-Derived Metal Catalysts

在线全文

学校读者我要写书评

暂无评论

Transactions of Tianjin University 2022年第2期28卷 89-111页

作者： Zhe-Hui Zhang Zhuohua sun Tong-qi Yuan Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing 100083China

With the world’s fossil fuels being finite in nature,an increasing interest focuses on the application of alternative renewable resources such as biomass.Biomass-derived platform chemicals with abundant functional groups have the potential to replace bulk chemicals for the production of value-added chemicals,fuels,and materials.The upgrading of these platform chemicals relies on the development of efficient catalytic systems.Hydrotalcite,with its wide compositional variety,tuneable anion-exchange capacity,and controlled acidity/basicity sites demonstrates great potential in the catalytic upgrading of biomass and the derived platform chemicals.The past decade has witnessed the emergence of research achievements on the development of efficient and robust hydrotalcite-derived metal catalysts and their applications in the upgrading of biomass or the derived platform chemicals.In this review,we aim to summarize the recent advances on the catalytic upgrading of biomass-derived platform chemicals(e.g.,furfural,5-hydroxymethylfurfural,levulinic acid,and glycerol)via hydrotalcitederived metal catalysts.We also observed that the crucial role of using hydrotalcite-derived catalysts relies on their strong metal–support interactions.As a result,a section focusing on the discussion of the metal–support interactions of hydrotalcitederived catalysts was provided.

关键词： Hydrotalcite Biomass Catalysis Metal-support interactions

Novel localized wave solutions of the (2+1)-dimensional Boiti–Leon–Manna–Pempinelli equation

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2020年第12期72卷 105-115页

作者： Li sun Jiaxin qi Hongli An College of Sciences Nanjing Agricultural UniversityNanjing210095China

Based on a special transformation that we introduce,the N-soliton solution of the(2+1)-dimensional Boiti–Leon–Manna–Pempinelli equation is constructed.By applying the long wave limit and restricting certain conjugation conditions to the related solitons,some novel localized wave solutions are obtained,which contain higher-order breathers and lumps as well as their interactions.In particular,by choosing appropriate parameters involved in the N-solitons,two interaction solutions mixed by a bell-shaped soliton and one breather or by a bell-shaped soliton and one lump are constructed from the 3-soliton solution.Five solutions including two breathers,two lumps,and interaction solutions between one breather and two bell-shaped solitons,one breather and one lump,or one lump and two bell-shaped solitons are constructed from the4-soliton solution.Five interaction solutions mixed by one breather/lump and three bell-shaped solitons,two breathers/lumps and a bell-shaped soliton,as well as mixing with one lump,one breather and a bell-shaped soliton are constructed from the 5-soliton solution.To study the behaviors that the obtained interaction solutions may have,we present some illustrative numerical simulations,which demonstrate that the choice of the parameters has a great impacts on the types of the solutions and their propagation properties.The method proposed can be effectively used to construct localized interaction solutions of many nonlinear evolution equations.The results obtained may help related experts to understand and study the interaction phenomena of nonlinear localized waves during propagations.

关键词： Boiti-Leon-Manna-Pempinelli equation Hirota bilinear method localized interaction wave solution

Interfacial engineering of perfluoroalkyl functionalized covalent organic framework achieved ultra-long cycled and dendrite-free lithium anodes

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第7期16卷 9289-9298页

作者： Yongxin Yang Conghui Zhang Zhiyuan Mei Yongjiang sun qi An qi Jing Genfu Zhao Hong Guo International Joint Research Center for Advanced Energy Materials of Yunnan Province Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon TechnologiesSchool of Materials and EnergyYunnan UniversityKunming 650091China

The finite lithium-ion utilization,short cycling life,and lower capacity retention caused by irreversible dendrite growth become the maximum dilemma in lithium metal batteries’(LMBs’)commercialization.Herein,a perfluoroalkyl-functionalized covalent organic framework(COF-F6)equipped with high stability and supernal proton conduction is introduced as an artificial solid electrolyte interface to stable the lithium metal anode.Benefiting from the strong electron-withdrawing effect of perfluoroalkyl,Li^(+)will be freed more by the competition of electronegative fluorine(F)and bis(trifluoromethanesulphonyl)imide anion(TFSI^(-)).The dissociation of LiTFSI and process of Li^(+)desolvation are easier to achieve.In addition,high electronegative fluorine can also regulate local electron-cloud density to induce the fast immigration of Li^(+).All the above roles contribute to improving the Li^(+)transfer number(0.7)and achieving the goal of inhibiting Li dendrite.As a result,the perfluoroalkyl COF-F6 modified LMB presents outstanding cycling stability.The symmetric batteries accomplish an overlong life-span of more than 5000 h with a lower hysteresis voltage(11 mV)at 5 mA·cm^(-2).Also,no dendrites are observed when using an in-situ optical microscope to learn the process of Li deposition.Therefore,this dendrite-free protection tactic holds broad prospects for the practical application of Li metal anodes.

关键词： perfluoroalkyl-functionalized covalent organic framework(COF-F6) artificial solid electrolyte interface strong electronwithdrawing effect dendrite-free lithium metal anode

Compact nano-void spectrometer based on a stable engineered scattering system

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2022年第10期10卷 2328-2336页

作者： Qi Sun PRZEMYSLAW FALAK TOM VETTENBURG TIMOTHY LEE DAVID BPHILLIPS GILBERTO BRAMBILLA MARTYNAS BERESNA Optoelectronics Research Centre University of SouthamptonSouthamptonSO171BJUK University of Dundee NethergateDundeeDD14HNUK University of Exeter ExeterEX44QLUK

Random scattering of light in disordered media can be used for highly sensitive speckle-based wavemeters and spectrometers. However, the multiple scattering events that fold long optical paths within a compact space also make such devices exceedingly sensitive to vibrations and small disturbances to the disordered media. Here, we show how scattering can be engineered so that it can be used for a compact computational spectrometer that is largely insensitive to environmental factors. We designed and fabricated a three-dimensional pseudo-random nano-void pattern with 62% scattering efficiency. The controlled amount of multiple scattering ensured a sufficiently long optical path for the target resolution of 100 pm, with optimal long-term stability. The 200-μm-thick scattering silica substrate was integrated in a compact assembly with a low-cost camera sensor. The target resolution was achieved for full spectrum measurements while single wavelengths could be determined with 50 pm resolution. Such tailored scattering systems can improve the trade-off among cost, size, stability, and spectral resolution in computational spectrometers.

关键词： stability disordered exceeding

Switching the coordination geometry to enhance erbium(Ⅲ)single-molecule magnets

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第5期34卷 535-538页

作者： qian-Cheng Luo Ning Ge Yuan-qi Zhai Tengbo Wang Lin sun Qi Sun Fanni Li Zhendong Fu Yan-Zhen Zheng Frontier Institute of Science and Technology School of Chemistry and School of PhysicsXi'an Jiaotong UniversityXi'an 710054China The School of Automation Science and Technology Xi'an Jiaotong UniversityXi'an 712000China Institute of Molecular and Crystal Engineering College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China Department of General Surgery The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061China Department of Talent Highland The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061China Neutron Platform Songshan Lake Materials LaboratoryDongguan 523808China

Two erbium(Ⅲ)complexes[ErCl(OAr^(Ad))_(3)][Na(THF)_(6)](1)and Er(OAr^(Ad))_(3)(2)are successfully prepared by using one variety of"hard"base ligand with large steric hindrance.The coordination geometry around the Er(Ⅲ)site changes from distorted tetrahedral to flat trigonal pyramid geometry in different solvent environment due to the removal of the coordinated chloride.Such an alternation significantly enhances the single-molecule magnet(SMM)behavior and makes the field-induced effective energy barrier(Ueff)arrive at 43(1)cm-1for the latter.Together with theoretical calculations,this study shows that strong equatorial ligand field and high local symmetry are critical to suppress the quantum tunneling of the magnetization(QTM)and achieve high-performance erbium(Ⅲ)based SMMs.

关键词： Single-molecule magnets Erbium Lanthanide complexes Magnetic anisotropy Slow magnetic relaxation

Age, Growth and Maturation of Largehead Hairtail (Trichiurus japonicus) in the East China Sea

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2022年第5期21卷 1244-1250页

作者： CHENG Shuo sun Peng LIU Yang CHEN qi SHI Zhengtong sun Runlong College of Fisheries Ocean University of ChinaQingdao 266003China College of Marine Life Sciences Ocean University of ChinaQingdao 266003China

Largehead hairtail(Trichiurus japonicus)is a commercially important fish species in China Seas,characterized by wide distribution,seasonal migration,spawning all year round.Under long-term high fishing pressure,the biological traits of largehead hair-tail have changed,such as miniaturization,smaller size-at-age and earlier age-at-maturation.To explore its current biological charac-ters,we analyzed age,growth and maturation of largehead hairtail in the East China Sea by analyzing the otolith microstructure and gonads.The results showed that largehead hairtail is mainly composed of 1 year and 2 years old individuals.The estimated von Ber-talanffy growth function(VBGF)showed significant differences between sexes,and asymptotic pre-anal length of male is longer than that of female.Two spawning seasons were observed in spring and autumn by monthly gonadosomatic index(GSI).Compared to historic survey data,the average pre-anal length at age decreased and size-at-maturation became smaller in the East China Sea.This study updates life history parameters of largehead hairtail,and provides a reference for the present status of largehead hairtail,which can contribute to largehead haritail stock assessment and sustainable utilization in the China Seas.

关键词： Trichiurus japonicus East China Sea age growth maturation

Coalitional game-based WiFi offloading algorithm in heterogeneous networks

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2019年第4期26卷 25-35页

作者： sun Lin Zhu qi Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China Engineering Research Center of Health Service System Based on Ubiquitous Wireless Networks Nanjing University of Posts and TelecommunicationsMinistry of EducationNanjing 210003China

Aiming at the coexistence of cellular network and wireless fidelity(WiFi)network,a coalitional game-based WiFi offloading algorithm in heterogeneous networks is proposed.Firstly,this paper defines the user fairness utility function that comprehensively considers the user communication rate,cost and delay.Then,the coalitional game model including two types of coalitions is constructed.To control the transfer of users among coalitions,a coalition transfer criterion that simultaneously improves the user's individual utility and the total system utility is proposed.In addition,this paper presents a channel allocation scheme that ensures full utilization of system resources to maximize the total utility of the system.The simulation results show that the proposed offloading algorithm can reasonably utilize the resources of cellular network and WiFi network,and improve the utility of users and system.

关键词： WiFi offloading fairness coalitional game resource allocation

Graphene-supported cobalt nanoparticles used to activate SiO_(2)-based anode for lithium-ion batteries

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第3期34卷 447-453页

作者： qi An Xiaohong sun Ying Na Shu Cai Chunming Zheng School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China School of Chemistry and Chemical Engineering State Key Laboratory of Hollow-fiber Membrane Materials and Membrane ProcessesTiangong UniversityTianjin 300387China

Although SiO_(2)-based anode is a strong competitor to supersede graphite anode for lithium-ion batteries,it still has problems such as low electrochemical activity, enormous loss of active lithium, and serious volume expansion. In order to solve these problems, we used a graphene network loaded with cobalt metal nanoparticles(rGO-Co) to coat SiO_(2) porous hollow spheres(SiO_(2)@rGO-Co). The construction of porous hollow structure and graphene network can shorten the lithium-ion(Li^(+)) diffusion distance and enhance the conductivity of the composite, which improves the electrochemical activity of SiO_(2) effectively. They also alleviate the volume expansion of the anode in the cycling process. Moreover,nano-scale cobalt metal particles dispersed on graphene catalyze the conversion reaction of SiO_(2) and activate the locked Li+in Li_(2)O through a reversible reaction, which improves the charge and discharge capacity of the anode. The capacity of SiO_(2)@rGO-Co reaches 370.4 m Ah/g after 100 cycles at 0.1 A/g,which is 6.19 times the capacity of pure SiO_(2)(59.8 mAh/g) under the same circumstance. What is more,its structure also exhibits excellent cycle stability, with a volume expansion rate of only 13.0% after 100 cycles at a current density of 0.1 A/g.

关键词： Lithium-ion batteries SiO_(2)-based anode Graphene network Co nanoparticles Electrochemical activity

Danshensu Ameliorates Cardiac Ischaemia Reperfusion Injury through Activating Sirt1/Fox01/Rab7 Signal Pathway

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Integrative Medicine 2020年第4期26卷 283-291页

作者： sun Da-wei GAO qing qi Xin Department of Neurology Tianjin Academy of Traditional Chinese Medicine Affiliated HospitalTianjin(300120)China School of Integrative Medicine Tianjin University of Traditional Chinese MedicineTianjin(301617)China Department of Cardiology Tianjin Union Medical CenterTianjin(300121)China

Objective:To explore the specific molecular mechanisms of Danshensu(DSS)in the treatment of ischemia reperfusion injury(IRI).Methods:IRI model was established with isolated rat hearts by performing global ischaemia for 30 min,and then followed by 60 min reperfusion.Also,H9C2 cells were subjected to 4-h hypoxia followed by 3-h reoxygenation.Then 10|i mol/L DSS were added in the reperfusion/reoxygenation step to intervene IRI.Cardiac function,structural change and apoptosis were respectively tested by Langendorff System,hematoxylin and eosin(HE)and terminal-deoxynucleotidyl transferase mediated nick endabeling(TUNEL)stainings.Then lactate dehydrogenase(LDH),cardiac troponin T(cTnT),reactive oxygen species(ROS),superoxide dismutase(SOD)and glutathione peroxidase(GSH-PX)were detected by enzyme-linked immunosorbent assay(ELISA).Sirt1/FoxO1/Rab7 Signal Pathway was monitored at both protein and mRNA levels.Results:The results showed that IRI not only greatly attenuated cardiac function(LVDP and±dp/dtmax,P<0.01,P<0.05)and increased the level of the marker enzymes(cTnT,LDH,P<0.01)from the coronary effluents,but also markedly induced changes in the structure of cardiomyocytes and contributed to apoptosis,which were mediated by boosted en doge nous ROS.However,after treatment with DSS all above indexes were improved,which was related to activating Sirt1/FoxO1/Rab7 signal pathway accompanied with the enhancement of antioxidant defense system,such as SOD and GSH-PX.Conclusion:DSS is able to protect hearts from IRI,which may be attributable to inhibiting excessive ROS through Sirt1/FoxO1/Rab7 signaling.

关键词： Chinese medicine Danshensu ischemia reperfusion injury Sirt1/FoxO1/Rab7 signal pathway reactive oxygen species apoptosis