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The influence of monomer concentration on the optical properties of electrochemically synthesized polypyrrole thin films

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Journal of semiconductors 2013年第10期34卷 13-18页

作者： J.V.Thombare M.C.Rath s.h.han V.J.Fulari holography and Material Research Laboratory Department of PhysicsShivaji UniversityKolhapur-416 004India Radiation and Photochemistry Division BARCMumbaiIndia Department of Chemistry Hanyang UniversitySeoulSouth Korea

Polypyrrole （PPy） thin films were deposited on stainless steel and ITO coated glass substrate at a constant deposition potential of 0.8 V versus saturated calomel electrode （sCE） by using the electrochemical polymerization method. The PPy thin films were deposited at room temperature at various monomer concentrations ranging from 0.1 M to 0.3 M pyrrole. The structural and optical properties of the polypyrrole thin films were investigated using an X-ray diffractometer （XRD）, FTIR spectroscopy, scanning electron microscopy （sEM）, and ultravioletvisible （UV-vis） spectroscopy. The XRD results show that polypyrrole thin films have a semi crystalline structure. higher monomer concentration results in a slight increase of crystallinity. The polypyrrole thin films deposited at higher monomer concentration exhibit high visible absorbance. The refractive indexes of the polypyrrole thin films are found to be in the range of 1 to 1.3 and vary with monomer concentration as well as wavelength. The extinction coefficient decreases slightly with monomer concentration. The electrochemically synthesized polypyrrole thin film shows optical band gap energy of 2.14 eV.

关键词： polypyrrole electrochemical polymerization method structure optical properties

The effects of electron irradiation on the optical properties of the organic semiconductor polypyrrole

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Journal of semiconductors 2013年第9期34卷 11-15页

作者： J.V.Thombare M.C.Rath s.h.han V.J.Fulari holography and Materials Research Laboratory Department of PhysicsShivaji University Radiation and Photochemistry Division BARC Department of Chemistry Hanyang University

The optical properties of polypyrrole （Ppy） thin films upon 2 MeV electron beam irradiation changes with different doses. The induced changes in the optical properties for Ppy thin films were studied in the visible range 300 to 800 nm at room temperature. The optical band gap of the pristine Ppy was found to be 2.19 cV and it decreases up to 1.97 eV for a 50 kGy dose of 2 MeV electron beam. The refractive index dispersion of the samples obeys the single oscillator model. The obtained results suggest that electron beam irradiation changes the optical parameters of Ppy thin films.

关键词： polypyrrole electron beam irradiation optical band gap

synthesis of Mesoporous Titanium silicate Materials with Mixture Mesophase

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Synthesis of Mesoporous Titanium Silicate Materials with Mix...

Trifluoromethylative homo-coupling of carbonyl compounds

中国化学会第十二届胶体与界面化学会议

作者： X.Yan~1,s.h.han~(2,*),W.G.hou~(2,*)and W.B.sun~3 1.school of medicine,shandong University of Traditional Chinese Medicine,science and Technology Zone of University, Changqin,Jinan,250355 2.Key Laboratory of Colloid and Interface science Chemistry,shandong University,27 shanda Nanlu,Jinan,250100 3.shanghai Research Institute of Petrochemical Technology,1658 Pudong Beilu, shanghai 201208

＜正＞Titanium-substituted zeolites show excellent catalytic properties in selective oxidation reactions. however,most of them are microporous solids and the pore-size limitation restricts their applications to the relatively lare molecules Therefore,many efforts have been dedicated to the synthesis of mesoporous titanium silicate materials.

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Chinese Chemical Letters 2025年第1期36卷 283-287页

作者： Xinlong han huiying Zeng Chao-Jun Li The state Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGill UniversityMontrealQuebecH3A 0B8Canada

Carbonyl compounds are abundant in nature and represent a substantial portion of biomass *** significant recent progress in homo-coupling of carbonyl compounds,achieving their deoxyfunctionalization homo-coupling remains a highly intricate ***,we report an entirely novel reaction paradigm:the trifluoromethylative homo-coupling of carbonyl compounds via hydrazones,which enables the formation of three C(sp^(3))-C(sp^(3))bonds in a single *** method provides a new pathway for synthesizing trifluoromethylative coupling product which has unique applications in both fields of medical and material *** investigations have unveiled that the formation of a trifluoromethyl-substituted benzyl radical plays a pivotal role as a key intermediate in this reaction.

关键词： Carbonyl compounds Trifluoromethylation homo-coupling C(sp^(3))-C(sp^(3))bond formation

Multi-frequency formation mechanism and modulation strategy of self-priming enhanced submerged pulsed waterjet

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International Journal of Mining science and Technology 2025年第2期35卷 175-189页

作者： Liu, Yanwei Jia, haojie Zuo, Weiqin han, hongkai Chang, Ping Ali Asad, Mohammad Waqar hu, Guozhong Miao, Jian Mitri, hani s. College of safety science and Engineering Henan Polytechnic University Jiaozuo454003 China henan International Joint Laboratory of Coal Mine safety and Occupational hazards Prevention and Control JiaoZuo454003 China Zhengzhou Institute for Advanced Research of henan Polytechnic University Zhengzhou451464 China WA school of Mines: Minerals Energy and Chemical Engineering Curtin University KalgoorlieWA6430 Australia school of Mines China University of Mining and Technology Xuzhou221116 China school of Intelligent Engineering Shandong Management University Jinan250357 China Department of Mining and Materials Engineering McGill University MontrealH3A0E8 Canada

Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets (sOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets (AFEsOPWs) exhibit a higher surge pressure through self-priming. however, their pressure frequency and cavitation characteristics remain unclear, resulting in an inability to fully utilize resonance and cavitation erosion to break coal and rock. In this study, high-frequency pressure testing, high-speed photography, and large eddy simulation (LEs) are used to investigate the distribution of the pressure frequency band, evolution law of the cavitation cloud, and its regulation mechanism of a continuous waterjet, sOPW, and AFEsOPW. The results indicated that the excitation of the plunger pump, shearing layer vortex, and bubble collapse corresponded to the three high-amplitude frequency bands of the waterjet pressure. AFEsOPWs have an additional self-priming frequency that can produce a larger amplitude under a synergistic effect with the second high-amplitude frequency band. A better cavitation effect was produced after self-priming the annulus fluid, and the shedding frequency of the cavitation clouds of the three types of waterjets was linearly related to the cavitation number. The peak pressure of the waterjet and cavitation erosion effect can be improved by modulating the waterjet pressure oscillation frequency and cavitation shedding frequency. © 2025

关键词： Cavitation

stabilizing water and regulating interfacial electrostatic interaction with economical supporting salt for stable Zn metal anode

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Journal of Energy Chemistry 2025年第2期101卷 429-436页

作者： Yiqun Du Rongkai Kang Boya Zhang han Wang Jianxin Zhang school of Material science & Engineering University of Jinan Key Laboratory for Liquid-solid structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University

Developing rechargeable aqueous Zn batteries for large-scale energy storage is impeded by inadequate reversibility and stability of the Zn anode,primarily caused by parasitic reactions and heterogeneous *** study proposes an economical electrolyte strategy to address these Zn-related *** addition of a supporting salt enhances the thermodynamic stability of water,reduces the number of highly reactive water molecules,and modulates the interfacial electrostatic *** approach effectively suppresses hydrogen evolution reaction and uncontrolled ***,the rationally proportioned electrolyte allows a high average Coulombic efficiency of 99.93% for 1000 cycles in a Zn‖Cu battery and a prolonged lifespan exceeding 4800 h in Zn‖Zn *** knock-on effect is that Zn‖MnO2pouch cells deliver stable cycling performance,demonstrating the viability of this approach for practical applications.

关键词： Aqueous electrolyte hydrogen bond sodium citrate solvation structure Zn anode

Phosphorylation modification reverses the transcriptional inhibitory activity of CsMYB4a in tea plants(Camellia sinensis)

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horticultural Plant Journal 2025年第1期11卷 406-416页

作者： Guoliang Ma Yunyun han Tongtong Li Tao Xia Liping Gao school of Life science Anhui Agricultural UniversityHefeiAnhui 230036China state Key Laboratory of Tea Plant Biology and Utilization Key Laboratory of Tea Biology and Tea Processing of Ministry of AgricultureAnhui Provincial Laboratory of Tea Plant Biology and UtilizationAnhui Agricultural UniversityHefeiAnhui 230036China

The members of the fourth subgroup of R2R3-MYB(sg4 members)are well-known inhibitors of phenylpropanoid and lignin synthesis *** C2 domain is closely related to the transcriptional inhibitory activity of sg4 *** modification enhances the transcriptional inhibitory activity of sg4 ***,we identified a phosphorylation site on the C2 domain of Cs MYB4a from tea plants(Camellia sinensis).A mitogen-activated protein kinase(MAPK),named Cs MPK3-2,phosphorylated this site on the C2 domain of Cs *** experiments revealed that phosphorylation of Cs MYB4a weakened its ability to inhibit the gene expression of PAL,C4h,and 4CL in the phenylpropanoid pathway and activated the expression of transcription factor YABBY5,maintaining the adaxial-abaxial polarity of the *** out Nt YAB5 in Cs MYB4a transgenic tobacco partially repaired the leaf wrinkling phenotype caused by Cs *** C1 domain exhibited an activation function when the C2 domain of Cs MYB4a was phosphorylated by Cs MPK3-2,causing this reversal *** results enrich our understanding of the regulatory diversity of sg4 members.

关键词： Camellia sinensis Cs MYB4a Phenylpropanoid pathway MAPK YABBY Leaf development

Uncovering the oxidation mechanism of sphalerite(Zns)in the absence and presence of water:A first-principles investigation

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International Journal of Mining science and Technology 2025年第1期35卷 149-157页

作者： Yuanjia Luo Wei sun haisheng han Jian Peng Feng Jiang school of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China

herein,a first-principles investigation was innovatively conducted to research the surface oxidation of Zns-like sphalerite in the absence and presence of h_(2)O .The findings showed that single O_(2) was preferred to be dissociated adsorption on sphalerite surface by generating sAO and Zn AO bonds,and the s atom on the surface was the most energy-supported site for O_(2) adsorption,on which a≡Zn-O-s-O-Zn≡structure will be ***,dissociated adsorption of single h_(2)O will not *** was preferred to be adsorbed on the top Zn atom on sphalerite surface in molecular form through Zn-O ***,sphalerite oxidation can occur as if O_(2) was present regardless of the presence of h_(2)O ,and when h_(2)O and O_(2) coexisted,the formation of sulfur oxide(sO_(2) )needed a lower energy barrier and it was easier to form on sphalerite surface than that only O_(2) *** the absence of h_(2)O ,when sO_(2) was generated,further oxidation of which would form neutral zinc *** the presence of h_(2)O ,the formation of sO_(2) on sphalerite surface was easier and the rate of further oxidation to form sulfate was also ***,the occurrence of sphalerite oxidation was accelerated.

关键词： First-principles Oxidation sphalerite h_(2)O Lower energy barrier

Combining slow-release fertilizer and plastic film mulching reduced the carbon footprint and enhanced maize yield on the Loess Plateau

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Journal of Environmental sciences 2025年第1期147卷 359-369页

作者： Xiaoqing han Pengfei Dang Lechen Liao Fangqi song Miaomiao Zhang Maoxue Zhang Guoqing Li shuyue Wen Ning Yang Xiping Pan Xiaofan Wang WenWang Xiaoliang Qin Charles O.Joseph Kadambot h.M.siddique College of Agronomy Key Laboratory of Crop Physi-ecology and Tillage Science in Northwestern Loess PlateauNorthwest A&F UniversityYanglingShaanxi 712100China Department of Crop sciences and Beekeeping Technology College of Agricultural sciences and Food Technology University of Dar es SalaamMwalimu Julius Nyerere Mlimani CampusP.O.Box 35091Dar es SalaamTanzania College of Life science Yulin UniversityChongwen Road No.4YulinShaanxi719000China The UWA Institute of Agriculture and school of Agriculture&Environment The University of Western AustraliaPerth WA 6001Australia

Agricultural practices significantly contribute to greenhouse gas(GhG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize *** film mulching is commonly used in the Loess Plateau *** slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop *** these techniques represents a novel agricultural approach in semi-arid ***,the impact of this integration on soil carbon storage(sOCs),carbon footprint(CF),and economic benefits has received limited research ***,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-s),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-s)]on soil fertility,economic and environmental *** results revealed that nitrogen fertilizer was the primary contributor to total GhG emissions(≥71.97%).Compared to other treatments,PM-s increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-s decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-s increased sOCs(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-s on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.

关键词： Plastic film mulching slow-release fertilizer Maize grain yield Carbon footprint Economic benefits