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Forest Ecosystems 2024年第1期11卷 14-23页

作者： sisira Ediriweera Champika bandara Tithira Lakkana shanika Jayasinghe David Woodbury Arun Dayanandan b.M.P.singhakumara Xiangcheng Mi I.A.u.N.Gunatilleke C.V.s.Gunatilleke Mark sAshton Department of science and technology Uva Wellassa UniversityBadullaSri Lanka The Forest school Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental science University of Sri JayewardenepuraNugegodaSri Lanka state Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China botany Department University of PeradeniyaPeradeniyaSri Lanka

background:No studies have documented long-term trends in aboveground biomass(AGb)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial *** our study,we sought to document such trends over forty years across three sites representing lowland to lower montane ***:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth *** measured trees for diameter at breast height that we identified to species and *** took wood samples to calculate species wood-specific *** re-measured plots in 1998 and again in ***:We show standing AGb for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).No differences exist among sites in AGb primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the *** few species represented a high proportion of the AGb with the top five species comprising between 34%and 65%,depending upon site and year *** species,Mesua nagassarium,represented a disproportionately large amount of AGb and decline over time,particularly at the low elevation ***:Our results are directly relevant to estimating AGb and standing carbon sequestered in *** study is the first to demonstrate varying but overall,declining trends in amounts of AGb among forests making predictions of biomass and standing carbon in MDF difficult over wide regions.

关键词： Western ghats shorea spp. southeast Asia sri Lanka Tropical rain forest Wood specific gravity

Protein-activated atomic layer deposition for robust crude-oil-repellent hierarchical nano-armored membranes

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science bulletin 2024年第2期69卷 218-226页

作者： Xiaobin Yang Pan sun Yajie Wen Anil u.Mane Jeffrey W.Elam Jun Ma shaomin Liu seth b.Darling Lu.s.a. MIIT Key Laboratory of Critical Materials technology for New Energy Conversion and storage State Key Laboratory of Urban Water Resource and EnvironmentSchool of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China Chemical sciences and Engineering Division Argonne National LaboratoryLemont IL 60439USA Applied Materials Division Argonne National LaboratoryLemont IL 60439USA Advanced Materials for Energy-Water systems Energy Frontier Research Center Argonne National LaboratoryLemont IL 60439USA Pritzker school of Molecular Engineering University of ChicagoChicago IL 60637USA Department of Physics University of Ilinois at ChicagoChicago IL 60607USA school of Environment Harbin Institute of TechnologyHarbin 150090China WA school of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerth WA 6845Australia

Atomic layer deposition(ALD)offers unique capabilities to fabricate atomically engineered porous materials with precise pore tuning and multi-functionalization for diverse applications like advanced membrane separations towards sustainable energy-water ***,current ALD technique is inhibited on most non-polar polymeric membranes due to lack of accessible nucleation ***,we report a facile method to efficiently promote ALD coating on hydrophobic surface of polymeric membranes via novel protein activation/*** a proof of concept,TiO2 ALD-coated membranes activated by bovine serum albumin exhibit remarkable superhydrophilicity,ultralow underwater crude oil adhesion,and robust tolerance to rigorous environments including acid,alkali,saline,and *** importantly,excellent cyclable crude oil-in-water emulsion separation performance can be *** mechanism for activation/sensitization is rooted in reactivity for a particular set of amino ***,the universality of protein-sensitized ALD is demonstrated using common egg white,promising numerous potential usages in biomedical engineering,environmental remediation,lowcarbon manufacturing,catalysis,and beyond.

关键词： Membrane separation Atomic layer deposition Water treatment Antifouling

A multi-dimensional microcanonical Monte Carlo study of s_0→T_1 intersystem crossing of isocyanic acid

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science China chemistry 2009年第11期52卷 1885-1891页

作者： ZHANG Feng1,2,FANG WeiHai1,LuO Yi2 & LIu RuoZhuang1 1 College of chemistry,beijing Normal university,beijing 100875,China 2 Theoretical chemistry,school of biotechnology,Royal institute of technology,s-10691 stockholm,sweden College of chemistry Beijing Normal University Beijing China Theoretical chemistry School of Biotechnology Royal Institute of Technology Stockholm Sweden

A general formula for the multi-dimensional Monte Carlo microcanonical nonadiabatic rate constant expressed in configuration space is applied to calculate the rate of intersystem crossing(IsC) between the ground(s0) and first excited triplet(T1) states for isocyanic ***-,two-and three-dimensional potential energy surfaces are constructed by coupled-cluster single-double CCsD calculations,which are used for Monte Carlo *** calculated s0→T1 IsC rate is in good agreement with experimental findings,which gives us a reason to believe that the multi-dimensional Monte Carlo microcanonical nonadiabatic rate theory is a very effective method for calculating nonadiabatic transition rate of a polyatomic molecule.

关键词： multi-dimensional Monte Carlo microcanonical nonadiabatic rate theory intersystem crossing isocyanic acid nonadiabatic transition

CHIRAL CONJugaTED OLIGOMER bAsED ON 1,1’-bINOL WITH 3,3’-ACETYLENE-PHENYLENE-ACETYLENE sPACER

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Chinese Journal of Polymer science 2001年第5期19卷 521-526页

作者： Tian-jun Liu Ke-shen Zhang Yong-jun Chen Dong Wang Chao-jun Li Center for Molecular science, institute of chemistry Chinese Academy of sciences, beijing 100080 China Department of chemistry Tulane university New Orleans, LA 70118 u.s.a. 中科院化学所北京 Tulane university 美国

The 1,2'-binaphthol based oligomers 3 and 7 with 3,3'-acetylene-phenylene-acetylene spacer were prepared from bINOL 1. The high optical rotation value and CD spectra demonstrated the main chain chirality of the oligomer molecule. The uV-VIs and fluorescent spectra evidence the characteristics of conjugated structure. In comparison with oligomer 2 bearing 3,3'-acetylene spacer, the oligomers 3 and 7 have longer efficient conjugation segment, and their fluorescent quantum yields (phi) increased (0.60-0.65 versus 0.14). Extending the effective conjugation segment would improve the photophysical properties of chiral conjugated polymers.

关键词： chiral conjugated oligomer bINOL 3,3 '-acetylene-phenylene-acetylene spacer

Excellent photoluminescence and electrochemical properties of sm^(3+) doped Ca_(2)Mgsi_(2)O_(7) nanophosphor:Display and electrochemical sensor applications

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Journal of Rare Earths 2024年第6期42卷 1046-1055,I0002页

作者： R.b.basavaraj K.sureshkumar D.P.Aarti M.b.Madhusudana Reddy G.Nagaraju T.Ramakrishnappa G.R.Navyashree K.R.Venkatesha babu K.s.Hemalatha Department of Physics BMS Institute of Technology and ManagementBangalore560064India Department of chemistry BMS Institute of Technology and ManagementBangalore560064India Department of chemistry School of Applied SciencesREVA UniversityBangalore560064India Energy Materials ResearchLaboratory Department of ChemistrySiddaganga Institute of TechnologyTumakuru57203KarnatakaIndia school of Physical sciences REVA UniversityBangalore560057Indi Department of Physics Govt.Science CollegeBengaluru560001India Department of Physics Maharani Science College for WomenMaharani Cluster UniversityBengaluru560001India

A series of orange-red light emitting Ca_(2)Mgsi_(2)O_(7):sm^(3+)nanopowders were fabricated via low-cost ecofriendly green combustion technique using Aloe vera gel as *** phase purity of the samples were confirmed by the powder X-ray diffraction(PXRD)*** single-phase tetragonal structure is observed from the PXRD results with no additional impurity *** band gap energy of the fabricated powders was estimated by diffuse reflectance spectra(DRs)and is found to be in the range of 4.01-5.98 eV.A high resolution scanning electron microscope(sEM)was used to study the morphological behaviour of the ***-like structures are observed from the sEM *** particle size was evaluated by transmission electron microscopy(TEM)and is found to be~50 *** interplanar distance is found to be 0.53 *** properties were systematically studied in *** phosphors are successfully excited at 403 nm NuV light,producing reddish-orange characteristic *** emission peaks are centered at 558(^(4)G_(5/2)→^(6)H_(5/2)),607(^(4)G_(5/2)→^(6)H_(7/2))and 645 nm(^(4)G_(5/2)→^(6)H_(9/2)),*** the observed peaks the red emanation(^(4)G_(5/2)→^(6)H_(7/2))is stronger than the orange emission(^(4)G_(5/2)→^(6)H_(5/2))in the current *** photoluminescent concentration quenching is noticed above 5 mol%sm^(3+)ion doping *** dipole-dipole interaction resulting in cross relaxation is found to be the principal cause of concentration quenching *** color features such as Commission Internationale de I’Eclairage(CIE)and correlated color temperature(CCT)were studied in *** optimized chromaticity coordinates were estimated to be(0.6363,0.3632),which fall in the reddish-orange *** average CCT value obtained is 3362 *** average color purity is found to be~82%.sm^(3+)incorporated Ca_(2)Mgsi_(2)O_(7) samples are possible contender for single white light generation commercial candidates owing to

关键词： Green combustion Photoluminescence Orange-red emission Color purity sensors Rare earths

Investigation of 'chazi'(damaged-enamels)on Chenghua doucai Porcelains

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science China(Technological sciences) 2009年第6期52卷 1722-1729页

作者： Du Feng1 & su baoRu2 1 institute of chemistry & Molecular Engineering,Qingdao university of science & technology,Qingdao,China 2 College of Information science & technology,Qingdao university of science & technology,Qingdao,China institute of chemistry & Molecular Engineering Qingdao University of Science & Technology Qingdao China College of Information science & technology Qingdao University of Science & Technology Qingdao China

At the end of the 1950s,sun Yingzhou considered that the 'chazi'(damaged colour)on Chenghua doucai imperial porcelain as a defect was originally produced in firing process during Chenghua period(1465―1487).Researchers in China have accepted his *** any fragment with the 'chazi' has never been found in several tons of Chenghua imperial sherds excavated from Ming imperial kiln site in *** China,few scholars have questioned the formation of 'chazi',and further investigated *** researchers at the Research Laboratory in the british Museum,employing unde-structive EDXRF,have analyzed the chemical composition of the 'chazi'(damaged colour)on a Chen-ghua doucai stem cup in the museum,and they have confirmed that the 'chazi'(damaged colour)was caused by the fire of the Jianfu palace in the Forbidden City in *** on their research,the authors studied the colour chemical principle of the 'chazi's' formation *** to the ceramic technology principle,scientific reasoning for the 'chazi' was carried *** the help of the history of Qing court,the brainteaser of the 'chazi' was totally uncovered,the misunderstanding for the 'chazi' has also been *** research also suggests that employing modern science and technology is a direction to study Chinese ancient ceramic further.

关键词： Chenghua doucai porcelains court eunuchs the set on fire at the Jianfu palace ’chazi’(damaged-enamels) the british Museum colour chemical principle archaeology using science and technology

surface tension of liquid Au-bi-sn alloys

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Rare Metals 2012年第3期31卷 250-254页

作者： Guo, Zhongnan Li, shan Mikula, Adolf Yuan, Wenxia Department of chemistry School of Chemical and Biological Engineering University of Science and Technology Beijing Beijing 100083 China institute of Inorganic chemistry/Material chemistry University of Vienna A-1090 Vienna Austria

The surface tension of a promising lead-free solder Au-bi-sn alloys was investigated both by the sessile-drop method and calculation. Experimental measurements were carried out for two cross-sections with the constant gold to bismuth ration of 1:1 and 1:2. For all the investigated compositions, decrease of the surface tension is observed with increasing temperature. Meanwhile, the surface tension values were also calculated based on butler’s equation, with using the newest research on thermodynamics data of Au-bi-sn ternary system. Compared with the experimental results, a good agreement was obtained.

关键词： sessile-drop method Au-bi-sn alloys density surface tension butler’s equation

Photodecomposition of H_2s to H_2 over Cd_xZn_(1-x)s composite photocatalysts

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Rare Metals 2009年第2期28卷 137-141页

作者： bai, Xuefeng Wu, Dan Wang, Peng school of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Heilongjiang institute of Petrochemistry Harbin 150040 China school of chemistry and Material science Heilongjiang University Harbin 150080 China

A series of CdxZn1-xs (x = 0.1-0.9) photocatalysts were prepared by coprecipitation. They could form solid solution semiconductors with hexagonal phase in agreement with pure Cds by characterization of XRD. The photophysical properties of CdxZn1-xs photocatalysts were measured by uV-Vis diffuse reflectance spectrum and surface photovoltage spectroscopy (sPs). The band gap energy gradually reduced with the increasing of x value in CdxZn1-xs,and when x = 0.7,the Cd0.7Zn0.3s photocatalyst had the strongest sur...

关键词： hydrogen production photodecomposition composite photocatalyst solid solution semiconductor

Quantum mechanical reaction dynamics in collisions of chlorine atom with hydrogen molecule

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Chinese Journal of chemistry 1994年第3期12卷 213-222页

作者： Meishan ZHAO The James Franck institute, the university of Chicago, Chicago, Illinois 60637, u.s.a. The James Franck institute the University of Chicago Chicago Illinois 60637 U.S.A.

We report the accurate determinations of quantum mechanical state-to-state probabilities tor reactions Cl + H2 - HCl + H and H' + HCl - H'Cl + H by the generalized Newton variational principle, on the most accurate available potential energy surface. We compare the results for three versions of realistic potential energy surfaces, and to those from hyperspherical close-coupling calculations.

关键词： Triatomic collision reactive scattering Green's function reactance matrix scattering matrix reactive transition probability.