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Linking individual-tree and whole-stand models for forest growth and yield prediction

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Forestry Studies in China 2014年第3期16卷 177-184页

作者： Quang v cao School of Renewable Natural Resources Louisiana State University Agricultural Center

Background： Different types of growth and yield models provide essential information for making informed decisions on how to manage forests. Whole-stand models often provide well-behaved outputs at the stand level, but lack information on stand structures. Detailed information from individual-tree models and size-class models typically suffers from accumulation of errors. the disaggregation method, in assuming that predictions from a whole-stand model are reliable, partitions these outputs to individual trees. On the other hand, the combination method seeks to improve stand-level predictions from both whole-stand and individual-tree models by combining them. Methods： Data from 100 plots randomly selected from the Southwicte Seed Source Study of Ioblolly pine （Pinus taedo L） were used to evaluate the unadjusted individual-tree model against the disaggregation and combination methods. Results： Compared to the whole-stand model, the combination method did not show improvements in predicting stand attributes in this study. the combination method also did not perform as well as the disaggregation method in tree-level predictions. the disaggregation method provided the best predictions of tree- and stand-level survival and growth. Conclusions： the disaggregation approach provides a link between individual-tree models and whole-stand models, and should be considered as a better alternative to the unadjusted tree model.

关键词： Disaggregation Combination method Loblollv pine Pinus taeda

Solvent-salt synergy offers a safe pathway towards next generation high voltage Li-ion batteries

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Science China Materials 2018年第10期61卷 1360-1362页

作者： Guozhong cao Department of Materials Science and Engineering University of Washington

Driven by expanding applications in mobile electronics,grid storage,and electric vehicles,the global lithium-ion battery market is projected to reach>45 billion dollars by2022[1].While each of these applications has a... 详细信息

关键词：电解质锂电池电池行业技术创新

Influence of alkali metal doping on surface properties and catalytic activity/selectivity of cao catalysts in oxidative coupling of methane

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Journal of Natural Gas Chemistry 2008年第4期17卷 313-320页

作者： v.H.Rane S.t.Chaudhari v.R.Choudhary Chemical Engineering and Process Development Division National Chemical Laboratory

Surface properties （viz. surface area, basicity/base strength distribution, and crystal phases） of alkali metal doped cao （alkali metal/Ca= 0.1 and 0.4） catalysts and their catalytic activity/selectivity in oxidative coupling of methane （OCM） to higher hydrocarbons at different reaction conditions （viz. temperature, 700 and 750 ℃; CH4/O2 ratio, 4.0 and 8.0 and space velocity, 5140-20550 cm^3 ·g^-1·h^-1） have been investigated. the influence of catalyst calcination temperature on the activity/selectivity has also been investigated. the surface properties （viz. surface area, basicity/base strength distribution） and catalytic activity/selectivity of the alkali metal doped cao catalysts are strongly influenced by the alkali metal promoter and its concentration in the alkali metal doped cao catalysts. An addition of alkali metal promoter to cao results in a large decrease in the surface area but a large increase in the surface basicity （strong basic sites） and the C2＋ selectivity and yield of the catalysts in the OCM process. the activity and selectivity are strongly influenced by the catalyst calcination temperature. No direct relationship between surface basicity and catalytic activity/selectivity has been observed. Among the alkali metal doped cao catalysts, Na-cao （Na/Ca = 0.1, before calcination） catalyst （calcined at 750 ℃）, showed best performance （C2＋ selectivity of 68.8% with 24.7% methane conversion）, whereas the poorest performance was shown by the Rb-cao catalyst in the OCM process.

关键词： oxidative coupling of methane alkali metal doped cao catalysts basicity/base strength distribution catalytic activity/selectivity

Synthesis of nitrogen-tethered 1,6-enynes through CuI/tFA catalysis

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Organic Chemistry Frontiers 2022年第2期9卷 394-399页

作者： Leilei cao Liliang Huang Xianjun Xu Erik v.van der Eycken Huangdi Feng College of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai201620China Laboratory for Organic&Microwave-Assisted Chemistry(LOMAC) Department of ChemistryKU LeuvenCelestijnenlaan 200FLeuvenB-3001Belgium Shanghai Peoples’Friendship University of Russia(RUDN University) Miklukho-Maklaya Street 6Moscow117198Russia Shanghai Frontiers Science Research Center for Druggability of Cardiovascular noncoding RNA Institute for Frontier Medical TechnologyShanghai University of Engineering ScienceShanghai201620China

A novel method for the concise and effective construction of nitrogen-tethered 1,6-enynes in moderate to good yields was *** transformation involves a tFA-promoted Pictet-Spengler reaction/iminium formation,copper-catalyzed alkyne-iminium ene reaction/alkynylation of a 2-arylethan-1-amine,formaldehyde solution,and a terminal *** process features exclusive chemoselectivity,simple operation,and high atom *** experimental studies suggest that the alkyne-iminium ene reaction involving an intermolecular hydride transfer is the key step in the current methodology.

关键词： catalysis hydride promoted

Encapsulating metal organic framework into hollow mesoporous carbon sphere as efficient oxygen bifunctional electrocatalyst

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National Science Review 2020年第3期7卷 609-619页

作者： Wanfeng Xiong Hongfang Li Hanhui You Minna cao Rong cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences College of Chemistry and Materials Science Fujian Normal University

Applying metal organic frameworks(MOFs) in electrochemical systems is a currently emerging field owing to the rich metal nodes and highly specific surface area of MOFs. However, the problems for MOFs that need to be solved urgently are poor electrical conductivity and low ion transport. Here we present a facile in situ growth method for the rational synthesis of MOFs@hollow mesoporous carbon spheres(HMCS)yolk–shell-structured hybrid material for the first time. the size of the encapsulated Zeolitic Imidazolate Framework-67(ZIF-67) is well controlled to 100 nm due to the spatial confinement effect of HMCS, and the electrical conductivity of ZIF-67 is also increased significantly. the ZIF@HMCS-25% hybrid material obtained exhibits a highly efficient oxygen reduction reaction activity with 0.823 v(vs. reversible hydrogen electrode) half-wave potential and an even higher kinetic current density(JK= 13.8 m A cm-2) than commercial Pt/C. ZIF@HMCS-25% also displays excellent oxygen evolution reaction performance and the overpotential of ZIF@HMCS-25% at 10 m A cm-2 is 407 m v. In addition, ZIF@HMCS-25% is further employed as an air electrode for a rechargeable Zn–air battery, exhibiting a high power density(120.2 m W cm-2 at 171.4 m A cm-2) and long-term charge/discharge stability(80 h at 5 m A cm-2). this MOFs@HMCS yolk–shell design provides a versatile method for the application of MOFs as electrocatalysts directly.

关键词： metal organic frameworks yolk–shell structure bifunctional electrocatalyst Zn–air battery

Synergetic effects of gold-doped copper nanowires with low Au content for enhanced electrocatalytic CO_(2)reduction to multicarbon products

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Nano Research 2023年第5期16卷 7777-7783页

作者： Zongnan Wei Shuai Yue Shuiying Gao Minna cao Rong cao Department of Chemistry University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Fujian Science&technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

As efficient catalysts of electrochemical CO_(2)reduction reaction(CO_(2)RR)towards multicarbon(C_(2+))products,Cu-based catalysts have faced the challenges of increasing the reactive activity and ***,we decorated the surface of Cu nanowires(Cu NWs)with a small amount of Au nanoparticles(Au NPs)by the homo-nucleation *** the Au to Cu mass ratio is as little as 0.7 to 99.3,the gold-doped copper nanowires(Cu-Au NWs)could effectively improve the selectivity and activity of CO_(2)RR to C_(2+)resultants,with the Faradaic efficiency(FE)from 39.7%(Cu NWs)to 65.3%,the partial current density from 7.0(Cu NWs)to 12.1 mA/cm^(2) under−1.25 v *** hydrogen electrode(RHE).the enhanced electrocatalytic performance could be attributed to the following three synergetic *** addition of Au nanoparticles caused a rougher surface of the catalyst,which allowed for more active sites ***,Au sites generated*CO intermediates spilling over into Cu sites with the calculated efficiency of 87.2%,which are necessary for multicarbon ***,the interphase electron transferred from Cu to Au induced the electron-deficient Cu,which favored the adsorption of*CO to further generate multicarbon *** results uncovered the morphology,tandem,electronic effect between Cu NWs and Au NPs facilitated the activity and selectivity of CO_(2)RR to multicarbons.

关键词： electrochemical CO_(2)reduction multicarbon production bimetallic catalyst Cu nanowires Au nanoparticles

Hybrid bimetallic cluster ZrO_(2)/Rh@N,S co-doped porous carbon nanosheets for efficient hydrogen evolution in acid electrolytes

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tungsten 2024年第4期6卷 657-662页

作者： Xin-Yi Zhang Igor v.Zatovsky Jun-Ming cao Xing-Long Wu Faculty of Chemistry Northeast Normal UniversityChangchun130024China F.D.Ovcharenko Institute of Biocolloidal Chemistry NAS UkraineKiev03142Ukraine MOE Key Laboratory for Uv Light-Emitting Materials and technology Northeast Normal UniversityChangchun130024China

Acid hydrogen evolution reaction(HER)is a critical energy conversion process,which is significantly important in hydrogen energy manufacturing and storage[1].Although the performance of noble metal platinum(Pt)-based catalysts in acidic HER is well known,the challenges are high cost,limited reserves,poor stability,and susceptibility to toxic substances[2].therefore,it is urgent to design and manufacture acidic HER catalysts with high reactivity,high stability,and low cost.

关键词： stability cluster porous

SHRIMP Zircon U-Pb Age of the Piqiang Layered Intrusion in the tarim Large Igneous Province and Subducted Slab-Plume Interaction in Its Petrogenesis

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1651-1652页

作者： cao Jun Fundamental Science on Radioactive Geology and Exploration technology Laboratory East China University of Technology School of Earth Sciences East China University of Technology

Objective During the Permian, at least four mafic continental large igneous provinces （LIPs） were tbrmed in eastern Asia, i.e., the Siberian traps （-251 Ma）, Emeishan LIP （-260 Ma）, tarim LIP （-290-270 Ma） and Panjal traps （-290 Ma）（Shellnutt et al., 2015）. the Emeishan and tarim LIPs in China are both known for the presence of several magmatic Fe-ti-v oxide deposits hosted in layered mafic- ultramafic intrusions. the origin of such magmatic Fe-ti- v oxide deposits is enigmatic. One of the long-lasting debates is the mechanism by which large amounts of Fe-ti oxides accumulated in the layered intrusions. Regardless of mechanism, there is still considerable debate regarding the mantle source compositions of the Fe-ti-v oxide ore- bearing intrusions, in the tarim LIP, a giant Fe-ti-v oxide deposit is hosted by the Piqiang layered intrusion at the northern margin of the tarim block. this intrusion consists mainly of gabbro and minor plagioclase-bearing clinopyroxenite and anorthosite （Fig. l a）. For this study we present new SHRIMP zircon U-Pb age and whole-rock geochemical data for the Piqiang layered gabbroic intrusion to evaluate the nature of its possible source compositions, which in turn aids in understanding the formation of the giant Fe-ti-v oxide deposit in the plume- related LIPs.

关键词： SHRIMP Zircon U-Pb Age of the Piqiang Layered Intrusion in the tarim Large Igneous Province and Subducted Slab-Plume Interaction In ta Pb

Molecular Design of tPD-based Organic A-π-D-π-A Dyes for Dye-sensitized Solar Cells

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Chemical Research in Chinese Universities 2013年第2期29卷 355-360页

作者： cao Xing-bo College of Petroleum and Chemical Engineering Dongying Vocational College Dongying 257091 P. R. China

An interesitng class of organicA-π-D-π-A dyes based on an N,N,N＇,N＇-tetraphenylbenzidine（tPD） unit as donor was designed and synthesized for dye-sensitized solar cells（DSSCs）. tPD-4-based DSSCs gave a short circuit photocurrent density（Jsc） of 16.67 mA/cm2, a open circuit voltage（voc） of 0.635 v and a fill factor（f/） of 0.68, achieving a solar-to-electricity conversion efficiency（r/） of 7.22% in preliminary tests. the N3-sensitized device gave an η value of 8.02% with a Jsc of 18.81 mA/cm2, a voc of 0.630 v and anffof 0.68 under the same conditions. the incident photo-to-current efficiency（IPCE） values above 70% observed in a range of 460 to 600 nm with a maximum value of 80% at 500 nm indicate that the tPD-4-based DSSC shows a high performance. Under the same conditions, the DSSC based on N3 provided the IPCE values above 70% in a range of 490 to 580 nm with a maximum value of 76% at 500 nm. Both further optimization of the device processing and structural modification of these dyes are an- ticipated to make the device give even better performances.

关键词： N,N,N',N'tetraphenylbenzidine(tPD) unit Dye-sensitized solar cell Solar-to-electricity conversionefficiency