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Photolysis studies on HCOOH and HCOO^- in presence of TiO_2 photocatalyst as suspension in aqueous medium

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Journal of natural gas Chemistry 2009年第1期18卷 50-54页

作者： g. r. Dey K. n. r. nair K. K. Pushpa radiation and Photochemistry Division Bhabha Atomic Research Centre Trombay Mumbai 400 085 India

Photolysis studies on formic acid （HCOOH） and formate ion （HCOO-） in presence of TiO2, a photocatalyst, as suspension in water were carried out separately using 350 nm ultraviolet light. The products, such as H2, CO, CO2 and CH4, generated during the experiments were monitored with varying the ambient, light exposure time, and the concentration of HCOOH/HCOO-. The yields of CO in all these systems increased with light exposure time. In aerated systems, CO yields were higher in contrast to the deoxygenated （Ar-purged） systems under identical conditions. It is proposed apparently that the formation of CO is taking place during the chemical reduction of in-situ generated CO2, a photo-mineralized product of HCOOH/HCOO-, but not through the direct photodecomposition or photodehydration （CO＋H2O） of solute molecules. The rates of CO formation during 1.3 M HCOOH photolysis in presence of TiO2 photocatalyst were evaluated to be 0.21 and 0.13 μl/min in aerated and Ar-purged systems, respectively. As compared with HCOOH systems, the CO yields are lower when 0.2 M HCOOna was exposed to light under identical conditions. The CO growth rates were evaluated to be 0.07 and 0.046 μl/min^-1 for aerated and deoxygenated HCOOna systems, respectively; moreover, the trend is quite similar to that of the HCOOH system. Under these conditions, the emission of H2 was also observed, and its yield was significantly higher in Ar-purged system as compared with the CO yields. However, in aerated system, the yields of these products were just opposite. The formation of low yield of methane was observed during photolysis of HCOOH/HCOO ions. In CO2 ambient, the yields of CO and H2 varied drastically with time.

关键词： formic acid formate ion photolysis TiO2

Endangered lowland oak forest steppe remnants keep unique bird species richness in Central Hungary

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Journal of Forestry research 2022年第1期33卷 343-355页

作者： gáborÓnodi Zoltán Botta‑Dukát Dániel Winkler Tamás rédei Institute of Ecology and Botany Centre for Ecological ResearchVácrátótHungary Department of Botany and Biodiversity research University of ViennaViennaAustria Institute of Wildlife Management and Wildlife Biology University of SopronSopronHungary

The biodiversity of natural or semi-natural native,old oak woodlands have high conservation importance,especially in landscapes of monocultural forest plantations and arable *** a wider variety of microhabitats and foraging sources,such old oak forests can provide essential habitat for native forest bird *** conducted a study using bird point counts to compare the forest bird communities of old pedunculate oak(Quercus robur)remnants with native and non-native plantations in central Hungary in a landscape of mostly arable fields,settlements,and monocultural *** surveys were carried out in old oak forest remnants,middle-aged oak,white poplar(Populus alba),hybrid poplar(Populus×euramericana),black locust(robinia pseudoacacia),and pine(Pinus spp.)*** has been carried out in nine study sites,where all six habitat types were represented(with a few exceptions),to determine total abundance,species richness,Shannon–Wiener diversity,species evenness,dominant and indicator species,and guild *** found that old oak forest remnants were the most diverse habitats among the studied forest types,while hybrid poplar and pine plantations exhibited the lowest avian *** avian guilds most sensitive to the loss of old oak forest remnants were ground foragers,bark foragers,cavity-nesters,residents,and Mediterranean migratory *** habitats were more diverse than non-native *** results suggest that it is important to conserve all remaining high biodiversity old oak stands and to avoid clear-cutting of monocultural plantations in favour of practices such as mixed-species plantations,longer rotation lengths,or retention forestry.

关键词： Forest bird community Bird conservation Old oak forest-steppe remnant Plantation forestry Forest conservation non-native plantation

Olfactory receptors in neural regeneration in the central nervous system

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neural regeneration research 2025年第9期20卷 2480-2494页

作者： rafael Franco Claudia garrigós Toni Capó Joan Serrano-Marín rafael rivas-Santisteban Jaume Lillo Molecular neurobiology Laboratory Department of Biochemistry and Molecular BiomedicineFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain Ciberned network Center for Biomedical research in neurodegenerative Diseases Spanish National Health Institute Carlos ⅢMadridSpain School of Chemistry Universitat de BarcelonaBarcelonaSpain Department of Biochemistry and Physiology School of Pharmacy and Food SciencesUniversitat de BarcelonaBarcelonaSpain Laboratory of Computational Medicine Biostatistics UnitFaculty of MedicineAutonomous University of BarcelonaCampus BellaterraBarcelonaSpain

Olfactory receptors are crucial for detecting odors and play a vital role in our sense of smell,influencing behaviors from food choices to emotional *** receptors also contribute to our perception of flavor and have potential applications in medical diagnostics and environmental *** ability of the olfactory system to regenerate its sensory neurons provides a unique model to study neural regeneration,a phenomenon largely absent in the central nervous *** gained from how olfactory neurons continuously replace themselves and reestablish functional connections can provide strategies to promote similar regenerative processes in the central nervous system,where damage often results in permanent *** the molecular and cellular mechanisms underpinning olfactory neuron regeneration could pave the way for developing therapeutic approaches to treat spinal co rd injuries and neurodegenerative diseases like Alzheimer's *** ctory receptors are found in almost any cell of eve ry orga n/tissue of the mammalian *** ectopic expression provides insights into the chemical structures that can activate olfactory *** addition to odors,olfactory receptors in ectopic expression may respond to endogenous compounds and molecules produced by mucosal colonizing *** analysis of the function of olfactory receptors in ectopic expression provides valuable information on the signaling pathway engaged upon receptor activation and the receptor's role in proliferation and cell differentiation *** review explo res the ectopic expression of olfa ctory receptors and the role they may play in neural regeneration within the central nervous system,with particular attention to compounds that can activate these receptors to initiate regenerative *** suggests that olfactory receptors could serve as potential therapeutic targets for enhancing neural repair and recovery following central nervous syste

关键词： adenosine receptors adrenergic receptors ectopic expression g proteincoupled receptors glia neurons

Lattice thermal conduction in cadmium arsenide

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Chinese Physics B 2022年第11期31卷 424-430页

作者： r F Chinnappagoudra M D Kamatagi n r Patil n S Sankeshwar Department of Physics S.S.Government First Grade CollegeNargund-582207KarnatakaIndia research resource Centre Visvesvaraya Technological UniversityBelagavi-590018KarnatakIndia Department of Physics B V B College of Engineering and TechnologyHubliKarnataka 80031India Department of Physics&Electronics CHRIST(Deemed to be University)Bangalore-560029KarnatakaIndia

Lattice thermal conductivity(LTC)of cadmium arsenide(Cd_(3)As_(2))is studied over a wide temperature range(1–400 K)by employing the Callaway *** acoustic phonons are considered to be the major carriers of heat and to be scattered by the sample boundaries,disorder,impurities,and other phonons via both Umklapp and normal phonon *** calculations of LTC of Cd_(3)As_(2)bring out the relative importance of the scattering *** systematic analysis of recent experimental data on thermal conductivity(TC)of Cd_(3)As_(2)samples of different groups,presented in terms of LTC,κL,using a nonlinear regression method,reveals good fits to the TC data of the samples considered for Tnd suggests a value of 0.2 for the gruneisen *** is,however,found that for T>100 K the inclusion of the electronic component of TC,κe,incorporating contributions from relevant electron scattering mechanisms,is needed to obtain good agreement with the TC data over the wide temperature *** detailed investigations of TC of Cd_(3)As_(2)are required to better understand its suitability in thermoelectric and thermal management devices.

关键词： dirac semimetals Cd_(3)As_(2) thermal conductivity phonon scattering

Estimation of Basal Area in West Oak Forests of Iran Using remote Sensing Imagery

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International Journal of geosciences 2012年第2期3卷 398-403页

作者： Loghman.ghahramany Parviz Fatehi Hedayat ghazanfari Department of Forestry College of Natural Resources University of Kurdistan Sanandaj Iran remote Sensing Laboratories Department of Geography University of Zurich Zurich Switzerland

The objective of this study is to evaluate the capability of satellite imagery for the estimation of basal area in northern Zagros Forests. The data of the high resolution geometric (Hrg) sensor of SPOT-5 satellite dated in July 2005 were used. Investigation of the quality of Satellite images shows that these images have no radiometric distortion. Overlaying of geocoded images with the digital topographic maps indicated that the images have high geometric precision. A number of 319 circular plots (0.1 ha) were established using systematic random method in the study area. All trees having diameter at breast height (DBH) (i.e. 1.3 m above ground) greater than 5 cm were callipered in each plot. Basal area in each plot was determined using field data. Main bands, artificial bands such as vegetation indices and principle component analysis (PCA) were studied. Digital numbers related to each plot were extracted from original and artificial bands. All plots were ordinated by major geographic aspects and the best fitted regression models were determined for both the study area without consideration of aspects and with consideration of major geographic aspects by multiple regression analysis (step wise regression). The results from regression analysis indicated that the square root of basal area without consideration of aspects has a high correlation with band B1 (r = –0.60). The consideration of aspects resulted in correlation of different indices with square root of basal area such that in northern forests, band B1 had higher correlation coefficient(r = –0.67) among other indices. In Eastern forests, the same band showed correlation of basal area with different correlation coefficient (r = –0.65). In southern and western forests, the square root of basal area had higher correlation (r = –0.68) with rVI. The use of the square root of basal area as a dependent variable in multivariate linear regression improved the results. The assessment of model validity indicated that the

关键词： northern Zagros Forests Basal Area SPOT-5 Data

nature of light scalars through photon-photon collisions

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Chinese Physics C 2010年第6期34卷 807-815页

作者： n.n.Achasov g.n.Shestakov Laboratory of Theoretical Physics Sobolev Institute for Mathematics

The surprising thing is that arising almost 50 years ago from the linear sigma model （LSM） with spontaneously broken chiral symmetry, the light scalar meson problem has become central in the nonperturbative quantum chromodynamics （QCD） for it has been made clear that LSM could be the low energy realization of QCD. First we review briefly signs of four-quark nature of light scalars. Then we show that the light scalars are produced in the two photon collisions via four-quark transitions in contrast to the classic P wave tensor qq mesons that are produced via two-quark transitions γγ→qq. Thus we get new evidence of the four-quark nature of these states.

关键词： linear sigma model light scalar mesons four-quark states two photon production mechanisms

resource-sharing strategies in ecotypes of the invasive clonal plant Carpobrotus edulis: specialization for abundance or scarcity of resources

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Journal of Plant Ecology 2017年第4期10卷 681-691页

作者： Josefina g.Campoy rubén retuerto Sergio r.roiloa Departamento de Biología Celular y Ecología Área de EcologíaFacultad de BiologíaCampus VidaUniversidade de Santiago de Compostela15782 Santiago de CompostelaSpain grupo BioCost Departamento de Biología AnimalBiología Vegetal y EcologíaÁrea de EcologíaFacultad de CienciasUniversidade da Coruña15071 A CoruñaSpain

Aims Carpobrotus edulis(L.)*** known to invade many coastal ecosystems around the world,and it has been considered as one of the most severe threats to numerous terrestrial plant ***,the study of the relationships between life-history traits that may favour its invasiveness and the invasibility of the environments is necessary to improve our knowledge about inva-sion *** this research,we specifically tested the effects of physiological integration in genotypes from contrasting habitats,where the importance of integration is expected to ***,the main objective of this work was to detect the presence of adaptive plasticity in the capacity for clonal integration in this aggressive *** In a greenhouse experiment,we compared the performance,in terms of growth and photochemical efficiency,of two *** *** and severed ramet pairs from coastal sand dunes and rocky coast habitats were grown in substrates of different quality and *** Findings Our study clearly indicates that clonal integration improves growth and photosynthetic efficiency in the aggressive invader *** differ-ent aspects of clonal integration determine site-specific strategies in this species in order to optimize its successful propagation in a particular *** demonstrated that the adaptation of *** to local envi-ronments has led to a differential selection of two complex clonal traits associated with the capacity for clonal *** patchy sand dunes,*** has evolved ecotypes with ramets highly plastic in patterns of biomass allocation,which allows ramets to specialize in the acquisi-tion of the resource that is locally most abundant,i.e.,a spatial division of labour among ***,in the harsher rocky coast habitats,local adaptation produced highly integrated ecotypes,where resource sharing is not combined with a specialization of resource acquisition.

关键词： adaptive plasticity biomass allocation Carpobrotus edulis chlorophyll fluorescence clonal integration

Field curing methods and storage duration affect the quality of hay from six rangeland grass species in Kenya

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Ecological Processes 2016年第1期5卷 32-37页

作者： O.K.Koech r.n.Kinuthia g.n.Karuku S.M.Mureithi r.Wanjogu Department of Land resource Management and Agricultural Technology Range Management SectionUniversity of NairobiP.O.Box 209053-00625NairobiKenya national Irrigation Board Mwea Irrigation Agricultural Development(MIAD)CentreP.O.Box 21010303 WanguruKenya

Introduction:rangelands are important source of pasture for livestock in Kenya since time immemorial to pastoral ***,seasonality on forage availability has been a big challenge in meeting animals’feed *** demands harvest and storage of pastures for use during dry *** making has been done to bridge this forage deficit ***,hay quality in the rangelands is affected by curing methods,phonological stage at harvest,and the storage *** therefore evaluated the effect of field curing and storage duration on the quality(Crude Protein(CP))of hay from six rangeland grasses in ***:The grasses evaluated are Chloris roxburghiana,Eragrostis superba,Enteropogon macrostachyus,Cenchrus ciliaris,Chloris gayana,and Sorghum *** grasses are the common species in the rangelands of Kenya and have been promoted in the past for hay making and reseeding *** grasses were harvested at the mature flowering stage(12 weeks phenological stage),which is a period that provides high biomass without much effect on quality as practiced in the study *** grasses were then cured in the field for 1,2,and 3 days before baling and stored indoors for 12,24,and 36 *** were taken for CP content determination at the three periods following Macro-Kjeldahl ***:There was significant decline(p≤0.05)in crude protein content in all the grass species with storage *** period did not affect the CP content for all the species at a given storage period;however,3 days curing changed the hay color from green to brownish which reduces palatability and consequently reduced feed *** period of over 12 weeks adversely lowered CP to less than 6% for all the species which is the required minimum level for animal under production and *** had significantly higher decline in CP after 24 weeks storage compared to the other ***:Therefore,hay from the six grass spec

关键词： grass quality range grasses Semi-arid rangelands grass storage grass curing Kenya

Leveraging rOTI map derived from Indonesian gnSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia

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Earth and Planetary Physics 2025年第1期9卷 101-116页

作者： Prayitno Abadi Ihsan n.Muafiry Teguh n.Pratama Angga Y.Putra Suraina gatot H.Pramono Sidik T.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.Tresna Asnawi research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory Management Facilities and Science and Technology Park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia research Center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian geospatial Information Agency(BIg) JakartaIndonesia research Center for Photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and Planetary Sciences Hokkaido UniversitySapporoJapan

This paper highlights the crucial role of Indonesia’s gnSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt gnSS signals and degrade positioning *** by the Indonesian geospatial Information Agency(BIg),the Indonesia Continuously Operating reference Station(Ina-COrS)network comprises over 300 gnSS receivers spanning equatorial to southern low-latitude ***-COrS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(rOTI)derived from this *** generate rOTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific *** preliminary findings from the rOTI maps of Ina-COrS are ***,the Ina-COrS rOTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined rOTI maps from Ina-COrS and gnSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined rOTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the g5 geomagnetic Storm on May 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing rOTI maps from Indonesia and integrating them with regional gnSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial Plasma Bubble(EPB) gnSS receivers’network Indonesia Continuously Operating reference Station(Ina-COrS) ionospheric map rate of TEC change index(rOTI)map