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Versatile zeolite overlayer on ZnO film enabling high-performance bilayer NO_(2) sensoring

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Nano Research 2024年第10期17卷 9193-9201页

作者： Tianshuang Wang Yiheng li Dan li Peng Sun Xiaowei Song Geyu lu Jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin University2699 Qianjin StreetChangchun 130012China State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China International Center of Future Science Jilin University2699 Qianjin StreetChangchun 130012China

Bilayer structure with functional overlayer has been commonly adopted to resolve the issue of moisture poisoning in ***,the conventional overlayers always suffer from blocking access of gas molecules to sensing layer due to lacking porosity and deteriorated adsorption ***,taking advantages of the well-defined porous structure and hydrophobic nature of pure silica zeolite,we assembled an overlayer of Pd-PdO clusters-encapsulated mesoporous silicalite-1(MFI)zeolite(named M-S-1)on ZnO sensing layer,to prevent moisture poisoning,and enhance gas diffusion and adsorption *** inherent capability of MFI zeolite to incorporate monodispersed nanometric(ca.3 nm)Pd-PdO cluster in its void space is of great importance for the NO_(2) *** Pd-PdO@M-S-1 overlayer can attain negligible moisture interference to the ZnO layer without significantly altering the gas selectivity and baseline resistance,and enhance gas ***,the Pd-PdO@M-S-1/ZnO bilayer sensor can ultra-selectively(S_(nitrogen dioxide)/S_(interference gas)>4),and ultra-stably detect trace level of NO_(2)(9.5 ppb)at low temperature(370 K)under high levels of humidity(90%RH).This work exemplifies a next-generation solution to design bilayer sensors using zeolite overlayer for eliminating the humidity dependence of the gas-sensing properties.

关键词： zeolites metal clusters bilayer structure NO_(2)chemiresistor

Femtosecond laser-induced periodic surface structures on hard and brittle materials

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Science china(Technological Sciences) 2024年第1期67卷 19-36页

作者： ZHAO GuoXu WANG Gong li yunFei WANG Lei liAN yuDong yu yu ZHAO Hui WANG yuLei lu ZhiWei Center for Advanced Laser Technology Hebei University of TechnologyTianjin 300401China Hebei Key Laboratory of Advanced Laser Technology and Equipment Tianjin 300401China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China School of Information and Electrical Engineering Hebei University of EngineeringHandan 056038China

Hard and brittle materials have high hardness,excellent optical stability,chemical stability,and high thermal ***,they have huge application potential in various fields,such as optical components,substrate materials,and quantum information,especially under harsh conditions,such as high temperatures and high *** laser direct writing technology has greatly promoted the development of femtosecond laser-induced periodic surface structure(Fs-liPSS or liPSS by a femtosecond laser)applications of hard and brittle materials due to its high precision,controllability,and three-dimensional processing *** far,liPSSs have been widely used in material surface treatment,optoelectronic devices,and ***,a consensus has not been reached regarding the formation mechanism of liPSSs on hard and brittle *** this paper,three widely accepted liPSS formation mechanisms are introduced,and the characteristics and applications of liPSSs on diamonds,silicon,silicon carbide,and fused silica surfaces in recent years are *** addition,the application prospects and challenges of liPSSs on hard and brittle materials by a femtosecond laser are discussed.

关键词： laser-induced periodic surface structures hard and brittle materials femtosecond laser

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Effects of gallium surfactant on AlN thin films by microwave plasma chemical vapor deposition

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Journal of Semiconductors 2024年第9期45卷 53-60页

作者： lu Wang Xulei Qin li Zhang Kun Xu Feng Yang Shaoqian lu Yifei li Bosen liu Guohao yu Zhongming Zeng Baoshun Zhang School of Physics Changchun University of Science and TechnologyChangchun 130013China Nanofabrication Facility Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China

In this work, AlN films were grown using gallium (Ga) as surfactant on 4° off-axis 4H-SiC substrates via microwave plasma chemical vapor deposition (MPCVD). We have found that AlN growth rate can be greatly improved due to the catalytic effect of trimethyl-gallium (TMGa), but AlN crystal structure and composition are not affected. When the proportion of TMGa in gas phase was low, crystal quality of AlN can be improved and three-dimensional growth mode of AlN was enhanced with the increase of Ga source. When the proportion of TMGa in gas phase was high, two-dimensional growth mode of AlN was presented, with the increase of Ga source results in the deterioration of AlN crystal quality. Finally, employing a two-step growth approach, involving the initial growth of Ga-free AlN nucleation layer followed by Ga-assisted AlN growth, high quality of AlN film with flat surface was obtained and the full width at half maximum (FWHM) values of 415 nm AlN (002) and (102) planes were 465 and 597 arcsec.

关键词： AlN thin film MPCVD gallium surfactant nucleation layer laser

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New material of Coniopteris simplex from the Middle Jurassic of the Ordos Basin,Inner Mongolia,china and implications on its spatio-temporal distribution and paleogeography

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Journal of Palaeogeography 2024年第2期13卷 199-211页

作者： yun-Feng li Chang-lu Zhang Fei liang Xiao Tan Fan-Hao Gong Chun-lin Sun Tao li yu-ling Na Research Center of Paleontology and Stratigraphy Jilin UniversityChangchun 130026Jilin ProvinceChina College of Earth Sciences Jilin UniversityChangchun 130061Jilin ProvinceChina College of Paleontology Shenyang Normal UniversityShenyang 110034Liaoning ProvinceChina Key Lab of Evolution of Past life in NE Asia Ministry of Natural ResourcesShenyang Normal UniversityShenyang 110034Liaoning ProvinceChina Shenyang Center of Geological Survey China Geological SurveyShenyang 110034Liaoning ProvinceChina

Coniopteris simplex is a common component in many Jurassic ***,due to morphological variations in sterile fronds and incomplete preservation of reproductive organs,its classification has been controversial for a long ***,we present new material collected from the Middle Jurassic Yan’an Formation in the Ordos Basin,Inner *** new material reveals important morphological characters,including hemi-dimorphic fronds,two forms of sterile pinnae,short-stalked sori and sporangia on fertile fronds,annulus of sporangium composed of about 30 cells,in situ rounded triangular spores with protruded suture,and the lips of trilete laesura encircled by one or two rows of small *** on these observations,we emended the diagnosis of this common *** spatio-temporal distribution of Coniopteris simplex shows that the iconic species was restricted to the paleolatitudes ranging from 19.5°N to 48.9°N in the Northern Hemisphere during the Early—Late Jurassic,mainly distributed in the tropical to paratropical zones,and the paleolongitude ranging from 9.6°E to 129.3°E,which may be limited by the opening of the Viking Corridor and the splitting of the Central Atlantic Ocean.

关键词： Coniopteris simplex Yan'an Formation Middle Jurassic Inner Mongolia Paleogeography

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Method with reliable accuracy and fast speed for measuring operational current of HTS NI closed-loop coils in steady persistent-current-mode

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Superconductivity 2024年第1期9卷 65-73页

作者： li lu Wei Wu Xin yu Zhuoyan Zhong Kai li Chengyun Pan Mengzhu li Zhijian Jin School of Electrical Engineering and Electronic Information Shanghai Jiao Tong UniversityMinghang District200240 ShanghaiPR China Shanghai Superconductor Technology Co. Ltd.Pudong New District201203 ShanghaiPR China CRRC changchun Railway Vehicles Co. Ltd.Changchun 130062JilinPR China

This study proposes a method for measuring the operational current of high temperature superconducting(HTS)non‐insulation(NI)closed‐loop coils,which operate in the steady persistent‐current‐mode(PCM).HTS NI closed‐loop coils are promising for many easily‐quenching direct‐current(DC)applications,where their performance is determined by magnetomotive forces,total number of turns,and *** the primary interface parameter in an application system,the operational current must be accurately and rapidly ***,this is achieved by dividing the measured magnetic field by the coil ***,even if the influence of the screening current induced field(SCIF)is not considered,existing methods for the coil constant may be disturbed by the performance and location of Hall sensors,or experience a long measuring ***,a relatively accurate and fast method is proposed in this study,which is based on adjusting the output current of the adjustable power supply and monitoring the coil voltage as an *** proposed method was validated through experiments and simulations using an equivalent circuit model coupled with a finite element method(FEM)model,and its current accuracy can be equivalent to the resolution of the employed power *** was demonstrated that this method reduced the requirements for Hall sensor’s performance and location,and has a more reliable accuracy in contrast to the simulation *** to the experimentally conventional method,the proposed method presents a significantly faster *** impact of the SCIF was considered and proven to be negligible for the tested pancake *** for coils whose coil constant vibrates owing to the SCIF,this method can be adapted to directly measure various operational ***,it was demonstrated that the measurement error can be influenced by the current discrepancy among turns when the coil is not in the steady PCM,and a procedure for reducing this error was pr

关键词： Operational current HTS NI closed‐loop coils Measurement method Adjustable power supply Coil voltage

Present Status and Future Prospects of the Mushroom Industry in china

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食用菌学报 2006年第1期 6-12页

作者： lu min, li yu*College of Agronomy, jilin agricultural university, changchun, jilin 130118, china

The present status and operation of the mushroom industry in china are summarized in terms of environmental and economic cycles, variety diversity, breeding of high quality varieties, features associated with developing mushroom industry models, evolving cultivation techniques, health functions and environmental protection. The advantages enjoyed by china′s mushroom industry such as strain resources, raw material and labor resources, and varied climatic conditions are also explored. Problems relating to resource protection, new germplasm preservation and breeding, variety protection and associated policies and laws, the need to manufacture finished and highly processed mushroom products, industrialization, industrial clustering, optimization of industry structure, mycology training, lack of multi-skilled teams with different experience levels, and the need to foster reserves of talent are discussed. Projections are also made for the future development of china′s mushroom industry.

关键词： Mushroom Industry development Cyclical economy Development mode Industrial clustering Status of mycology

Roles of Salicylic Acid-responsive Cis-acting Elements and W-boxes in Salicylic Acid Induction of VCH3 Promoter in Transgenic Tobaccos

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Acta Biochimica et Biophysica Sinica 2006年第1期38卷 46-52页

作者： Hai-Yan li~(1,2),Wei WEI~(2&),and yu li~(1*) ~1 Institute of Mycology,jilin agricultural university,changchun 130118,china ~2 College of Biotechnology,jilin agricultural university,changchun 130118,china Institute of Mycology Jilin Agricultural University Changchun 130118 China

A salicylic acid (SA)-inducible VCH3 promoter was recently identified from grapevine (Vitisarnurensis) that contains two inverse SA-responsive cis-acting elements and four *** furtherdemonstrate the roles of these elements,four fragments with lengths from-1187,-892,-589,-276 to+7 bp were fused with the β-glucuronidase (GUS) reporter géne and transferred to Nicotiana tobacum,together with another four VCH3 promoter fragments with mutation in the two inverse *** functions,of each promoter fragment were-examined by analysis of GUS activity in thetransgenic tobacco root treated with *** GUS activity was shown in the roots of transgenictobaccos with the VCH3 (-1187)-GUS construct containing two SA-responsive cis-acting elements andfour ***,GUS activity directed by the VCH3 (-892)-GUS construct,containing one SA cis-acting element and four W-boxes,was reduced by up to 35% compared with that in tobaccos transformedwith the VCH3 (-1187)-GUS construct,indicating that the SA cis-acting element plays an important role inSA induction of the VCH3 *** the m2VCH3 (-1187)-GUS nor the mVCH3 (-892)-GUSconstruct,with mutation on the SA-responsive elements,abolished the expression of GUS activity,demon-strating that the W-boxes in the VCH3 promoter are also involved in SA *** arialysis ofGUS activity directed by each of the eight VCH3 promoter fragments showed that GUS was expressedspecifically in vascular *** was concluded that both the SA-responsive cis-acting elements and the W-boxes are important for the SA induction of the VCH3 *** promoter might have a potential usein plant genetic engineering.

关键词： VCH3 promoter salicylic acid(SA)-responsive cis-acting element W-box site-directed mutagenesis SA induction transgenic tobacco

Reversibly Cross-linking Polyimide and Cyclophosphazene Toward Closed-Loop Recyclable Plastics with High Mechanical Strength,Excellent Flame Retardancy,and Chemical Resistance

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CCS Chemistry 2024年第4期6卷 976-987页

作者： Tingting Guan Xiaohan Wang Xi Zhao Xingyuan lu Xiu-li Wang yu-Zhong Wang Junqi Sun State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012 The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu 610064

Traditional flame-retardant plastics are technically difficult to chemically *** development of newtypes of flame-retardant plastics that are intrinsically capable of being closed-loop recycled and are sufficiently robust and stable to satisfy their practical application is urgently *** this study,closed-loop recyclable flame-retardant plastics with high mechanical strength and excellent chemical resistance are fabricated by cross-linking amino-terminated polyimide(PI-NH_(2))and aldehyde-terminated cyclophosphazene(CP-CHO)with imine *** resultant flame-retardant plastic,which is denoted as PI-CP,exhibits a tensile strength of∼115.6 MPa,Young’s modulus of∼2.5 GPa,and glass transition temperature of 316°*** the PI-CP plastic,the imine bonds are isolated within hydrophobic microenvironments generated by the rigid and hydrophobic polyimide chains and the benzene ring of *** a result,the PI-CP plastics are highly stable in highly acidic and basic aqueous solutions and other commonly used organic *** PI-CP plastic shows outstanding flame retardancy with a limiting oxygen index value of 48.8%.More importantly,the PI-CP plastic can be depolymerized to generate the original PI-NH_(2)and CPCHO monomers in high yields(∼97%)and *** recovered monomers can be used to refabricate the original plastics,establishing highly efficient polymer-monomer-polymer circulation and a sustainable plastics economy.

关键词： closed-loop recyclable plastics recyclable polymers reversibly cross-linked polymers flame retardancy supramolecular polymers

High quality repair of osteochondral defects in rats using the extracellular matrix of antler stem cells

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World Journal of Stem Cells 2024年第2期16卷 176-190页

作者： yu-Su Wang Wen-Hui Chu Jing-Jie Zhai Wen-Ying Wang Zhong-Mei He Quan-min Zhao Chun-Yi li Institute of Antler Science and Product Technology Changchun Sci-Tech UniversityChangchun 130000Jilin ProvinceChina College of Chinese Medicinal Materials Jilin Agricultural UniversityChangchun 130118Jilin ProvinceChina School of life Science Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina Department of Oral Implantology Hospital of StomatologyJilin UniversityChangchun 130000Jilin ProvinceChina

BACKGROUND Cartilage defects are some of the most common causes of *** lesions caused by inflammation,trauma or degenerative disease normally result in osteochondral *** studies have shown that decellularized extracellular matrix(ECM)derived from autologous,allogenic,or xenogeneic mesenchymal stromal cells(MSCs)can effectively restore osteochondral *** To determine whether the decellularized ECM of antler reserve mesenchymal cells(RMCs),a xenogeneic material from antler stem cells,is superior to the currently available treatments for osteochondral *** We isolated the RMCs from a 60-d-old sika deer antler and cultured them in vitro to 70%confluence;50 mg/mL L-ascorbic acid was then added to the medium to stimulate ECM *** sheets of adipocyte-derived MSCs(aMSCs)and antlerogenic periosteal cells(another type of antler stem cells)were used as the *** weeks after ascorbic acid stimulation,the ECM sheets were harvested and applied to the osteochondral defects in rat knee *** The defects were successfully repaired by applying the *** highest quality of repair was achieved in the RMC-ECM group both in vitro(including cell attachment and proliferation),and in vivo(including the simultaneous regeneration of well-vascularized subchondral bone and avascular articular hyaline cartilage integrated with surrounding native tissues).Notably,the antler-stem-cell-derived ECM(xenogeneic)performed better than the aMSC-ECM(allogenic),while the ECM of the active antler stem cells was superior to that of the quiescent antler stem *** Decellularized xenogeneic ECM derived from the antler stem cell,particularly the active form(RMC-ECM),can achieve high quality repair/reconstruction of osteochondral defects,suggesting that selection of decellularized ECM for such repair should be focused more on bioactivity rather than kinship.

关键词： Osteochondral defect repair Mesenchymal stem cells Extracellular matrix Decellularization Antler stem cells Reserve mesenchymal cells Xenogeneic