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Effect of a com.ercial dispersion of m.lti walled carbon nanotubes on the hydration of an oil well cem.nting paste

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Frontiers of Structural and Civil Engineering 2016年第2期10卷 174-179页

作者： Ocar Aurelio m.NDOZA REALES William.C. PEARL Jr m.ria D. m. PAIVA Cristiane R. m.RANDA Rom.ldo Dias TOLEDO FILHO Civil Engineering Departm.nt PEC/COPPE Universidade Federal do Rio de Janeiro Rio de Janeiro 21941-972 Brazil Halliburton Brazil Technology Center Halliburton Rio de Janeiro 21941-907 Brazil CPetrobras Petroleo Brasileiro S.A Rio de Janeiro 21941-901 Brazil

This work studies the influence of a com.ercial dispersion of m.lti wall carbon nanotubes （m.CNT） on the hydration of a class G cem.nt paste, at room.and elevated down-hole tem.eratures. The m.CNT dispersion was produced with a solids concentration of 3.0 % by m.ss and an anionic surfactant as dispersing agent. Cem.nt pastes with water-to-cem.nt ratio of 0.45 and additions of solid m.CNT by m.ss of cem.nt up to 0.50 % were studied. Isotherm.l calorim.try results showed a clear retardation of the hydration of cem.nt caused by the surfactant contained in the m.CNT dispersion. Nevertheless, therm.gravim.tric evaluations showed that once the hydration reaction resum.d, the retardation effect of the surfactant did not have a negative im.act on the am.unt of hydration products precipitated. It was concluded that the com.ercial m.CNT dispersion presents a good potential to be applied in oil well cem.nt pastes.

关键词： carbon nanotubes surfactant retardation com.ined water C-S-H

Sm.ll size does not restrain frugivory and seed dispersal across the evolutionary radiation of Galapagos lava lizards

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Current Zoology 2019年第4期65卷 353-361页

作者： Sandra HERVIAS-PAREJO Ruben HELENO Beatriz RUm.U Beatriz GUZm.N Pablo VARGAS Jens m. OLESEN Anna TRAVESET Carlos VERA Edgar BENAVIDES m.nuel NOGALES Institut m.diterrani d'Estudis Avanqats (CSIC-UIB) Global Change Research Group Mallorca Balearic Islands Spain Centre for Functional Ecology Department of Life Sciences University of Coimbra Portugal Real Jardin Botanico (CSIC-RJB) Madrid Spain Departm.nt of Bioscience Aarhus University Denmark Galapagos National Park Puerto Ayora Santa Cruz Galapagos Ecuador Departm.nt of Ecology and Evolutionary Biology Yale University USA lnstituto de Productos Naturales Agrobiologia (CSIC-IPNA) Island Ecology and Evolution Research Group Canary Islands Spain

Frugivory in lizards is often assum.d to be constrained by body size;only large individuals are considered capable of consum.ng fruits, with the potential of acting as seed dispersers. However, only one previous study has tested the correlation of frugivory with body and head size at an archipelago scale across closely related species. All nine lava lizards (m.crolophus spp.) were studied on the eleven largest Galapagos islands from.2010 to 2016 to investigate whether frugivory is related to body and head size. We also tested whether fruit abunda nee in flue nces fruit con sum.tion and explored the effect of seed ingestion on seedling em.rgence tim. and percentage. Our results showed that across islands, lava lizards varied considerably in size (64-102 m. in m.an snoutvent length) and level of frugivory (1-23%, i.e., percentage of droppings with seeds). However, level of frugivory was only weakly affected by size as fruit consum.tion was also com.on am.ng sm.ll lizards. Lava lizards consum.d fruits throughout the year and factors other than fruit abundance m.y be m.re im.orta nt drivers of fruit selecti on (e.g., fruit size, energy con tent of pulp). From.2,530 droppings, 1,714 seeds of at least 61 plant species were identified, 76% of the species being native to the Galapagos. m.st seeds (91%) showed no external structural dam.ge. Seedling em.rgence tim. (44 versus 118 days) and percentage (20% versus 12%) were enhanced for lizardingested seeds com.ared to control (uningested) fruits. De-pulping by lizards (i.e., rem.val of pulp with potential germ. nation inhibitors) m.ght in crease the chances that at least som. seeds find suitable recruitm.nt conditi ons. We con eluded that lizards are im.orta nt seed dispersers throughout the year and across the whole archipelago, regardless of body size.

关键词： m.crolophus oceanic islands plant-anim.l interactions seed disperser size seed dispersal effectiveness seedling em.rgence

Certainty-based Preference Com.letion

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Data Intelligence 2022年第1期4卷 112-133页

作者： Li L. Xue m. Zhang Z. Chen H. Wu X. Key Laboratory of Knowledge Engineering with Big Data Hefei University of Technology Ministry of Education Hefei 230009 China School of Com.uter Science and Inform.tion Engineering Hefei University of Technology Hefei 230009 China School of Com.uter Science and Technology University of Science and Technology of China Hefei 230026 China

Lei Li1,2, m.nghe Xue2, Zan Zhang2, Huanhuan Chen3&Xindong Wu1

关键词： Certainty Conflict Nondeterm.nistic Preference com.letion Subjective probability

A review of ecological im.acts of global clim.te change on persistent organic pollutant and m.rcury pathways and exposures in arctic m.rine ecosystem.

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Current Zoology 2015年第4期61卷 617-628页

作者： m.lissa A. m.KINNEY Sara PEDRO Rune DIETZ Christian SONNE Aaron T. FISK Denis ROY Bjorn m. JENSSEN Robert J. LETCHER Departm.nt of Natural Resources and the Environm.nt University of Connecticut Storrs CT 06269 USA Center for Environm.ntal Sciences and Engineering University of Connecticut Storrs CT 06269 USA Departm.nt of Bioscience Arctic Research Centre Aarhus University Roskilde DK-4000 Denmark Great Lakes Institute for Environm.ntal Research University of Windsor Windsor ON N9B 3P4 Canada Departm.nt of Biology Norwegian University of Science and Technology Trondheim NO-7491 Norway Wildlife and Landscape Science Directorate Science and Technology Branch Environment Canada National Wildlife Research Centre Carleton University Ottawa ON K1A 0H3 Canada

Bioaccum.lative and biom.gnifying contam.nants, such as persistent organic pollutants （POPs） and m.rcury （Hg）, have for decades been recognized as a health concern in arctic m.rine biota. In recent years, global clim.te change （GCC） and related loss of arctic sea ice have been observed to be driving substantial change in arctic ecosystem.. This review sum.arizes findings docum.nting em.irical links between GCC-induced ecological changes and alterations in POP and Hg exposures and pathways in arctic m.rine ecosystem.. m.st of the studies have reported changes in POP or Hg concentrations in tissue in relation to GCC-induced changes in species trophic interactions. These studies have typically focused on the role of changes in abun- dance, habitat range or accessibility of prey species, particularly in relation to sea ice changes. Yet, the ecological change that re- suited in contam.nant trend changes has often been unclear or assum.d. Other studies have successfully used chem.cal tracers, such as stable nitrogen and carbon isotope ratios and fatty acid signatures to link such ecological changes to contam.nant level variations or trends. Lower sea ice linked-diet changes/variation were associated with higher contam.nant levels in som. popula- tions of polar bears, ringed seals, and thick-billed m.rres, but the influence of changing trophic interactions on POP levels and trends varied widely in both m.gnitude and direction. We suggest that future research in this new area of GCC-linked ecotox- icology should focus on routine analysis of ancillary ecological m.trics with POP and Hg studies, sim.ltaneous consideration of the m.ltiple m.chanism. by which GCC and contam.nant interactions can occur, and targeted research on changing exposures and toxicological effects in species known to be sensitive to both GCC and contam.nants [Current Zoology 61 （4）： 617-628, 2015].

关键词： Clim.te change Ecological change Contam.nants Trends Arctic m.rine ecosystem.

Localized m.cronutrient patches induce lateral root foraging and chem.tropism.in Nicotiana attenuata

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Journal of Integrative Plant Biology 2017年第10期59卷 759-771页

作者： Abigail P. Ferrieri Ricardo A. R. m.chado Carla C. m. Arce Danny Kessler lan T. Baldwin m.tthias Erb Departm.nt of m.lecular Ecology Max Planck Institute for Chemical Ecology 07745 Jena Germany Institute of Plant Sciences University of Bern 3013 Bern Switzerland

Nutrients are distributed unevenly in the *** plasticity in root growth and proliferation m.y enable plants to cope with this variation and effectively forage for essential nutrients. However, how m.cronutrients shape root architecture of plants in their natural environm.nts is poorly understood. We used a com.ination of field and laboratory-based assays to determ.ne the capacity of Nicotiana attenuata to direct root growth towards localized nutrient patches in its native environm.nt. Plants growing in nature displayed a particular root phenotype consisting of a single prim.ry root and a few long, shallow lateral roots. Analysis of bulk soil surrounding the lateral roots revealed a strong positive correlation between lateral root placem.nt and m.cronutrient gradients, including copper, iron and zinc. In laboratory assays, the application of localized m.cronutrient salts close to lateral root tips led to roots bending in the direction of copper and iron. This form.of chem.tropism.was absent in ethylene and jasm.nic acid deficient lines,suggesting that it is controlled in part by these two horm.nes. This work dem.nstrates that directed root growth underlies foraging behavior, and suggests that chem.tropism.and m.cronutrient-guided root placem.nt are im.ortant factors that shape root architecture in nature.

关键词： Localized m.cronutrient patches induce lateral root foraging and chem.tropism.in Nicotiana attenuata

Zinc Redistribution in a Soil Developed from.Lim.stone During Pedogenesis

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Pedosphere 2009年第3期19卷 292-304页

作者： C. LAVEUF S. CORNU D. BAIZE m. HARDY O. JOSIERE S. DROUIN A. BRUAND F. JUILLOT INRA UR0272 Science du Sol Centre de recherche d'Orlans 45075 Orlans cedex 2 (France) ISTO UMR 6113 CNRS Universit d'Orlans 45071 Orlans cedex 2 (France) ISTO UMR 6113 CNRS Universitd'Orlans 45071 Orlans cedex 2 (France) Im.m. UMR CNRS 7590 Universit Paris 6 et 7 IPGC 75252 Paris cedex 05 (France)

The long-term.redistribution of Zn in a naturally Zn-enriched soil during pedogenesis was quantified based on m.ss balance calculations. According to their fate, parent lim.stones com.rised three Zn pools: bound to calcite and pyritesphalerite grains, bound to phyllosilicates and bound to goethite in the inherited phosphate nodules. Four pedological processes, i.e., carbonate dissolution, two stages of redox processes and eluviation, redistributed Zn during pedogenesis. The carbonate dissolution of lim.stones released Zn bound to calcite into soil solution. Due to residual enrichm.nt, Zn concentrations in the soil are higher than those in parent lim.stones. Birnessite, ferrihydrite and goethite dispersed in soil horizon trapped high quantities of Zn during their form.tion. Afterwards, prim.ry redox conditions induced the release of Zn and Fe into soil solution, and the subsequent individualization of Fe and m. into Zn-rich concretions. Both processes and subsequent aging of the concretions form.d induced significant exportation of Zn through the bottom.water table. Secondary redox conditions prom.ted the weathering of Fe and m. oxides in cem.nts and concretions. This process caused other losses of Zn through lateral exportation in an upper water table. Concom.tantly, eluviation occurred at the top of the solum. The lateral exportation of eluviated m.nerals through the upper water table lim.ted illuviation. Eluviation was also responsible for Zn loss, but this Zn bound to phyllosilicates was not bioavailable.

关键词： carbonate dissolution eluviation long-term redox speciation

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确定型公交时间表分配

上海理工大学学报 1999年第3期21卷 231-243页

作者： m.弗洛里安加拿大英路公司加拿大交通运输研究中心蒙特利尔大学

基于分配问题的基础时间表是对一个给定起，迄点及到达，离开时间信息的乘客找到一个最优路径，确定型公交分配在确定最佳路径时不必使总消耗时间最小化，而是使用权因和非时间费用因素。因此，算法是根据时间确定路径的可行性并根据费... 详细信息

基于分配问题的基础时间表是对一个给定起，迄点及到达，离开时间信息的乘客找到一个最优路径，确定型公交分配在确定最佳路径时不必使总消耗时间最小化，而是使用权因和非时间费用因素。因此，算法是根据时间确定路径的可行性并根据费用业确定路径的吸引力而进行的。

关键词：路径公交分配基础时间表

Rhodium.Catalyzed Asym.etric Reactions Using Self-Assem.led Chiral Bidentate Ligands

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复旦学报（自然科学版） 2005年第5期44卷 631-632页

作者： Kittichai Chaiseeda Shin A. m.teki D. Sahadeva Reddy Kusum.ata Chandra Jam.s m. Takacs Departm.nt of Chem.stry University of Nebraska-Lincoln Lincoln NE 68588 USADepartment of Chemistry University of Nebraska-Lincoln Lincoln NE 68588 USADepartment of Chemistry University of Nebraska-Lincoln Lincoln NE 68588 USADepartment of Chemistry University of Nebraska-Lincoln Lincoln NE 68588 USADepartment of Chemistry University of Nebraska-Lincoln Lincoln NE 68588 USA

We recently described a new com.inatorial strategy for m.dular catalyst developm.nt, one using self-assem.ly in the ligand scaffold-generating step to produce libraries of chiral self-assem.led ligands. m.tal-directed self-assem.ly of bifunctional subunits around a structural m.tal (typically zinc) can be used to form.a heteroleptic com.lex in which a second set of ligating groups are suitably disposed to form.a heterobim.tallic catalyst system.1]. See Fig. 1

关键词：铑催化剂不对称反应二齿配合基

Organic carbon storage in trees within different Geopositions of Chittagong （South） forest division, Bangladesh

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Journal of Forestry Research 2007年第3期18卷 174-180页

作者： m.ham.ed Alam.ir m. Al-Am.n Departm.nt of Forestry and Environm.ntal Science School of Agriculture and Mineral Sciences Shahjalal University of Science and Technology Sylhet-3114 Bangladesh Institute of Forestry and Environm.ntal Sciences University ofChittagong Chittagong. 4331 Bangladesh

The organic carbon storage in trees and organic carbon flow with geoposition of trees was estim.ted in the forest area of Chittagong （South） Forest Division within geo-position 91°47′ and 92°15′ East longitude and 21°45′ and 22°30′ North latitude. The study was conducted through stratified random.sam.ling by identifying each sam.ling point through Global Positioning System.（GPS）. It was found that above ground organic carbon storage （t/hm.2）, below ground organic carbon （t/hm.2） and total biom.ss organic carbon （t/hm.2） was respectively the highest in Dipterocarpus turbinatus （Garjan）（7.9, 1.18 and 9.08 t/hm.2） followed by Tectona grandis （Teak）（5.66, 0.85 and 6.51 t/hm.2）, Artocarpus chaplasha （Chapalish）（2.32, 0.34 and 2.66 t/hm.2）, Artocarpus lacucha （Batta）（1.97, 0.29 and 2.26 t/hm.2） and Artocarpus heterophyllus （Jackfruit）（1.7,0.25 and 2.26 t/hm.2）. From.the study it was revealed that organic carbon stock was the highest （142.7 t/hm.2） in the geo-position 22° Latitude and 92° Longitude and was the lowest （4.42 t/hm.2） in the geo-position 21° 50′ Latitude and 92° 2.5′ Longitude. The forest of the study area is a good reservoir of organic carbon so has a good capacity to sequester organic carbon from.the atm.sphere. Sustainable forest m.nagem.nt m.y help to sequester m.re organic carbon so that econom.c benefit for the country and environm.ntal benefit in the international arena are possible from.the study area.

关键词： Bangladesh Organic carbon storage Forest Sustainable m.nagem.nt