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VAMP726 from maize and Arabidopsis confers pollen resistance to heat and uv radiation by influencing lignin content of sporopollenin

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Plant Communications 2023年第6期4卷 163-178页

作者： Wenqi Yang Dongdong Yao Haiyang Duan Junli Zhang Yaling Cai Chen Lan Bing Zhao Yong Mei Yan Zheng Erbing Yang Xiaoduo Lu Xuehai Zhang Jihua Tang Ke Yu Xuebin Zhang State Key Laboratory of Crop Stress Adaptation and Improvement Henan Joint International Laboratory for Crop Multi-Omics ResearchSchool of Life SciencesHenan UniversityKaifeng 475004China National Key Laboratory of Wheat and Maize Crop Science College of AgronomyHenan Agricultural UniversityZhengzhou 450002China The Shennong Laboratory Zhengzhou 450002China College of Chemistry Zhengzhou UniversityZhengzhou 450001China National Engineering Laboratory of Crop Stress Resistance School of Life ScienceAnhui Agricultural UniversityHefei 230036China

Sporopollenin in the pollen cell wall protects male gametophytes from stresses.Phenylpropanoid derivatives,including guaiacyl(G)lignin units,are known to be structural components of sporopollenin,but the exact composition of sporopollenin remains to be fully resolved.We analyzed the phenylpropanoid derivatives in sporopollenin from maize and Arabidopsis by thioacidolysis coupled with nuclear magnetic resonance(NMR)and gas chromatography–mass spectrometry(GC–MS).The NMR and GC–MS results confirmed the presence of p-hydroxyphenyl(H),G,and syringyl(S)lignin units in sporopollenin from maize and Arabidopsis.Strikingly,H units account for the majority of lignin monomers in sporopollenin from these species.We next performed a genome-wide association study to explore the genetic basis of maize sporopollenin composition and identified a vesicle-associated membrane protein(ZmVAMP726)that is strongly associated with lignin monomer composition of maize sporopollenin.Genetic manipulation of VAMP726 affected not only lignin monomer composition in sporopollenin but also pollen resistance to heat and uv radiation in maize and Arabidopsis,indicating that VAMP726 is functionally conserved in monocot and dicot plants.Our work provides new insight into the lignin monomers that serve as structural components of sporopollenin and characterizes VAMP726,which affects sporopollenin composition and stress resistance in pollen.

关键词： pollen cell wall sporopollenin lignin monomers heat stress uv radiation

Formation of Natural Melanin/TiO_(2) Nanostructure Hybrids with Enhanced Optical,Thermal and Magnetic Properties as a Soft Material

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 613-620页

作者： Saja Algessair Nawal Madkhali Department of Physics College of ScienceImam Mohammad Ibn Saud Islamic University(IMSIU)P.O.Box 5701Riyadh 11432Saudi Arabia

The natural Melanin/TiO_(2) was synthesized by the use of ultrasonication under uv radiation.The influence of natural melanin on the structural,optical and thermal properties of TiO_(2) nanoparticles was investigated by using Fourier transform infrared spectroscopy,thermogravimetric analysis and uv-Vis spectroscopy.It was observed that incorporating natural melanin on TiO_(2) nanoparticles(TiO_(2)-Mel)occurred at 2.01 eV with a low value of Urbach energy around 100 meV indicating improvement in the crystalline structure.Magnetic measurement at room temperature showed diamagnetic behavior.Furthermore,thermal results showed that TiO_(2)-Mel is stable even at temperatures up to 400℃.According to the results obtained by the thermal stability of melanin with titanium dioxide,it can be a good candidate in many applications such as solar cells and optoelectronics.

关键词： natural melanin/TiO_(2) thermal stability optoelectronic nanostructure uv radiation

uv radiation INDUCED GRAFT COPOLYMERIZATION OF ALLYL ACETATE ONTO POLY(ETHYLENE TEREPHTHALATE)(PET) FILMS FOR FUEL CELL MEMBRANES

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Chinese Journal of Polymer Science 2012年第2期30卷 227-234页

作者： Mostak Ahmed Mubarak A.Khan Nazia Rahman M.Anwar H.Khan radiation and Polymer Chemistry Laboratory Institute of Nuclear Science and TechnologyBangladesh Atomic Energy CommissionP.O.Box 3787DhakaBangladesh Department of Chemistry Shahjalal University of Science and TechnologySylhet-3114Bangladesh Department of Geography University of California BerkeleyBerkeleyCA 94720USA

Ultraviolet （uv）-induced graft copolymerization of allyl acetate （AA） monomer onto poly（ethylene terephthalate）（PET） films and the subsequent sulfonation on the monomer units in the grafting chain using chlorosulfonic acid （C1SO3H） were carried out to prepare proton exchange membranes （PEMs） for fuel cells. A maximum grafting value of 12.8% was found for 35 vol% allyl acetate after 3 h radiation time. Optimum concentration of C1SO3H was selected for the sulfonation reaction to be 0.05 mol/L based on the degree of sulfonation and the tensile strength studies of the membrane. The degree of sulfonation increased as the sulfonation reaction temperature and sulfonation time were increasing. The radiation grafting and the sulfonation have been confirmed by titrimetric and gravimetric analyses as well as FTIR spectroscopy. The maximum ion exchange capacity （IEC） of 0.04125 mmol g-1 was found at 12.1% degree of sulfonation and the maximum proton conductivity was found to be 0.035 S cm-1 at 30℃ and a relative humidity of 60%. The various physical and chemical properties of the PEMs such as water uptake, mechanical strength, thermal durability and oxidative stability were also studied. To investigate the suitability of the prepared membrane for fuel cell applications, its properties were compared with those ofNafion 117.

关键词： Polymer electrolyte membrane Allyl acetate Fuel cell uv radiation Grafting Sulfonation.

Enhanced electrochemical oxidation of phenol by introducing ferric ions and uv radiation

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Journal of Environmental Sciences 2008年第11期20卷 1386-1391页

作者： MAO, Xuhui WEI, Lin HONG, Song ZHU, Hua LIN, An GAN, Fuxing School of Resource and Environmental Science Environmental Engineering Department Wuhan University Wuhan 430079 China

The mineralization of phenol in aerated electrochemical oxidation has been investigated.The results show that a cathodic Fenton process can occur when the Ti-0.3Mo-0.8Ni alloy material is used as cathode in solution containing ferric or ferrous ions; moreover,the reinforcement of cathodic Fenton process on the total organic carbon (TOC) removal rate of phenol is quite distinct.Among the metallic ions investigated,the ferric ion is the best catalyst for the electrochemical mineralization of phenol at initial...

关键词： mineralization phenol electrochemical oxidation cathodic Fenton process uv radiation

The adsorption behavior of metals in aqueous solution by microplastics effected by uv radiation

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Journal of Environmental Sciences 2020年第1期32卷 272-280页

作者： Qiongjie Wang Yong Zhang Xiaoxue Wangjin Yulai Wang Guanhua Meng Yihua Chen School of Energy and Environment Anhui University of Technology

Microplastics are considered as the carrier to heavy metals in the environment.But the sorption ability of microplastics influenced by photo-aging is remaining unclear.In the present study,the sorption of two kinds of metal ions(Cu^2+ and Zn^2+)in the aqueous solution by both the virgin and aged microplastics was investigated.Polyethylene terephthalate(PET)debris,one of the typical kinds of microplastics was chosen in this study.Photo-aging of microplastics in environment was simulated using uv radiation in the laboratory.Date analysis indicated that the aged microplastics had higher adsorption capacity of heavy metals than original ones.This could be related to the increased surface area and oxygen containing function appeared in the surface of aged microplastics after uv radiation.When prolonging the time of radiation,the enhanced adsorption capacities of microplastics appeared for Cu^2+ and Zn^2+.These results showed a great interaction between the aging degree of plastics and sorption capacity to heavy metals.Meanwhile,external conditions including temperature and pH value were also showed great influence to the adsorption behavior.

关键词： uv radiation Microplastics Adsorption Metal ions

Effects of ultraviolet(uv) radiation and litter layer thickness on litter decomposition of two tree species in a semi-arid site of Northeast China

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Journal of Arid Land 2018年第3期10卷 416-428页

作者： MAO Bing ZHAO Lei ZHAO Qiong ZENG Dehui CAS Key Laboratory of Forest Ecology and Management Institute of Applied Ecology Chinese Academy of Sciences College of Horticulture Jilin Agricultural University Daqinggou Ecological Station Institute of Applied Ecology Chinese Academy of Sciences

Forests and grasslands in arid and semi-arid regions receive high-intensity ultraviolet（uv） radiation year-round. However, how the uv radiation affects the litter decomposition on the forest floor remains unclear. Here, we conducted a field-based experiment in 2011 in the southeastern Horqin Sandy Land, Northeast China, to investigate the effects of uv radiation, litter layer thickness, and their interaction on the mass loss and chemical properties of decomposing litter from Xiaozhuan poplar（Populus × xiaozhuanica） and Mongolian pine（Pinus sylvestris var. mongolica） plantation trees. We found that uv radiation accelerated the decomposition rates of both the Xiaozhuan poplar litter and Mongolian pine litter. For both species, the thick-layered litter had a lower mass loss than the thin-layered litter. The interaction between uv radiation and litter layer thickness significantly affected the litter mass loss of both tree species. However, the effects of uv radiation on the chemical properties of decomposing litter differed between the two species, which may be attributed to the contrasting initial leaf litter chemical properties and morphology. uv radiation mostly had positive effects on the lignin concentration and lignin/N ratio of Xiaozhuan poplar litter, while it had negative effects on the N concentration of Mongolian pine litter. Moreover, litter layer thickness and its interaction with uv radiation showed mostly positive effects on the N concentration and lignin/N ratio of Xiaozhuan poplar litter and the ratios of C/N and lignin/N of Mongolian pine litter, and mostly negative effects on the C/N ratio of Xiaozhuan poplar litter and the N concentration of Mongolian pine litter. Together, these results reveal the important roles played by uv radiation and litter layer thickness in the process of litter decomposition in this semi-arid region, and highlight how changes in the litter layer thickness can exert strong influences on the photodegradation of litter in tree plantations.

关键词： lignin litter decomposition litter layer thickness nitrogen forest plantation photodegradation uv radiation

Oxidative Degradation of Thermoplastic Starch Induced by uv radiation

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Journal of Renewable Materials 2019年第4期7卷 383-391页

作者： Mayte M.Quispe Olivia V.López Marcelo A.Villar Planta Piloto de Ingeniería Química PLAPIQUI(UNS CONICET)Bahía Blanca(8000)Argentina Departamento de Ingeniería Química Universidad Nacional del Sur(UNS)Bahía Blanca(8000)Argentina

Among biopolymers,thermoplastic starch(TPS)is a good candidate to obtain biomaterials because of its natural origin,biodegradable character,and processability.Exposure to ultraviolet(uv)radiation causes significant degradation of starch-based materials,inducing photooxidative reactions which result in breaking of polymer chains,production of free radical,and reduction of molar mass.These changes produce a deterioration of TPS mechanical properties,leading to useless materials after an unpredictable time.In this work,changes induced on TPS by uv radiation,analyzing structural properties and mechanical behavior,are studied.TPS was obtained through thermo-mechanical processing of native corn starch in the presence of water(45%w/w)and glycerol(30%w/w)as plasticizers.Films were obtained by thermocompression and,before testing,specimens were conditioned to reduce material fragility.Photodegradation process was performed by exposing TPS to 264 h uv radiation in a weathering test chamber.Specimen’s weight loss was determined gravimetrically.Chemical changes were studied by Fourier Transform Infrared Spectroscopy(FTIR)and morphological modifications were analyzed by Scanning Electron Microscopy(SEM).Reduction of weight average molar mass was measured by Static Light Scattering(SLS).Changes in mechanical properties were studied from tensile tests.After 96 h exposure,TPS specimens presented a weight reduction of 4-6%,mainly attributed to plasticizers lost by evaporation.SEM observations showed that uv radiation induced morphological changes on TPS,evidenced by an increment of specimens cracking.By FTIR,it was detected the presence of an additional band located at 1726 cm-1 in samples submitted to uv radiation,attributed to the formation of-C=O groups.Weight average molar mass of native starch was in the order of 107 g mol-1.TPS exposure to uv radiation decreased significantly its molar mass,confirming molecular degradation of the biopolymer.When TPS was exposed during 48 h,it was detected a considerable decrease in elongati

关键词： Thermoplastic starch uv radiation structural properties mechanical behavior

Quasi-periodic pulsations with double periods observed in Lyαemission during solar flares

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Science China(Technological Sciences) 2022年第1期65卷 139-146页

作者： LI Dong Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033China CAS Key Laboratory of Solar Activity National Astronomical ObservatoriesBeijing 100101China

Quasi-periodic pulsations(QPPs)are very common oscillation features during solar flares,which have been observed in almost the entire wavelengths.However,the flare-related QPPs with double periods in the Lyα emission,particularly within a period ratio of about 2,were rarely detected.In this paper,we report the QPPs with double periods in the full-disk Lyαemission during the impulsive phase of four solar flares,i.e.,SOL2016-Feb-12,SOL2014-Oct-24,SOL2014-Jun-10,and SOL2012-Nov-21.The fulldisk Lyαfluxes were recorded by the extreme-ultraviolet sensor on board the Geostationary Operational Environmental Satellite.Then,the quasi-periods are estimated by the Markov chain Monte Carlo(MCMC)sampling techniques.Finally,the double periods of around 3 and 1.5 min are detected in Lyαemissions,and their period ratio is roughly equal to 2.The 3-min QPP could also be detected in the local light curves measured by the Atmospheric Imaging Assembly at wavelengths of 304 and 1600A.Our observations suggest that the double periodic QPPs could be regarded as the fundamental and harmonic modes of acoustic waves,which should be helpful to understand magnetohydrodynamic waves in the solar chromosphere.However,we cannot rule out that the double periods are each caused by a different generation mechanism.

关键词： solar flares solar chromosphere oscillations uv radiation magnetohydrodynamics(MHD)

Functionalized Graphene Oxide with Bismuth and Titanium Oxide Nanoparticles for Efficiently Removing Formaldehyde from the Air by Photocatalytic Degradation-Adsorption Process

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Journal of Analysis and Testing 2023年第4期7卷 444-458页

作者： Mohsen Mohammadi Asl Hamid Shirkhanloo Nabiollah Mansouri Seyed Ali Reza Haji Seyed Mirzahosseini Farideh Atabi Department of Environmental Engineering Faculty of Natural Resource and EnvironmentScience and Research BranchIslamic Azad UniversityTehran 14778-93855Iran Research Institute of Petroleum Industry(RIPI) West BoulevardOlympic VillageTehran 14857-33111Iran

Formaldehyde(HCHO)is formed through the oxidation of volatile organic compounds(VOCs)and can cause human cancer.Bismuth oxide and titanium oxide nanoparticles-functionalized nanographene oxide(Bi_(2)O_(3)/TiO_(2)@NGO)were used to rapidly remove the HCHO from the air by a photocatalytic degradation-adsorption process(PC-DAP).The formaldehyde vapor in pure air was generated in a dynamic system within a chamber,and flowed over Bi_(2)O_(3)/TiO_(2)@NGO adsorbent inside a fixed-bed quartz reactor(FBQR)under uv irradiation at optimized conditions(250C).At atmospheric pressure,the flow rate and gas hourly space velocity(GHSV)were adjusted to 300 mL/min and 100-450 L/h,respectively.The radicals of HCHO and nanographene oxide(NGO)were generated through the uv-photochemical process,enhancing the chemical adsorption through the radicals’interactions.On the other hand,the semi-degradation process by catalytic oxidation process converted some HCHO into raw materials of CO_(2)and H_(2)O,while the unconverted HCHO was physically absorbed by NGO.Finally,the HCHO concentration in the outlet system was measured by gas chromatography with a flame ionization detector(GC-FID)after derivatizing formaldehyde with 2,4-dinitrophenylhydrazine(DNPH)and acetonitrile.Therefore,efficient removal of HCHO from the air,the removal efficiency of more than 95%,was achieved through physical/chemical adsorption and the semi-degradation.The mean removal efficiencies for HCHO with Bi_(2)O_(3)-TiO_(2)@NGO,TiO_(2)@NGO,Bi_(2)O_(3)@NGO,and NGO were 98.7%,73.6%,61.8%,and 11.4%,respectively(n=10,RSD<5%).The methodology was validated by spiking different concentrations of standard HCHO into pure air.

关键词： Formaldehyde removal Air Functionalized graphene oxide uv radiation Photocatalytic degradation-adsorption process