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Potential adaptation of a Q biotype whitefly population from poinsettia to field crops

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Insect Science 2011年第6期18卷 719-728页

作者： Xiangshun Hu Timothy j. Dennehy Xinzhi Ni Huiyan Zhao Robert l. Nichols Xianchun li College of Plant Protection NorthwestA ＆ F University Yangfing Shaanxi Province China Department of Entomology and BI05 Institute University of Arizona Tucson Arizona USDA-ARS Crop Genetics and Breeding Research Unit Tifton Georgia Cotton Incorporated Cary North Carolina USA

The invasive Q biotype whitefly was first detected in the US on poinsettia in 2004 and is still not a pest outside of greenhouse environments in the US. To assess the potential for the establishment of the Q biotype on field crops, population cage experiments were conducted to compare the performance of a poinsettia-derived Q population named P＇06 on poinsettia and six field crops （alfalfa, tomato, melon, cotton, cowpea and cabbage）. P＇06 adults reared on poinsettia as nymphs laid eggs on all six field crops. Significantly more eggs were laid on alfalfa, tomato, melon and cotton than on cabbage, cowpea and poinsettia. These eggs hatched and the nymphs developed to adults on the six field crops. Relative to poinsettia, whitefly survival was similar on cowpea, alfalfa, tomato and cabbage, but significantly higher on cotton and melon. Moreover, P＇06 had significantly shorter development times from egg to adult on cotton, melon, cowpea, tomato and alfalfa than they did on poinsettia. However, the F1 adults raised on the six field crops had significantly shorter lifespans and laid 11- to 18-fold fewer eggs than did the F1 adults raised on poinsettia. Taken together, while P＇06 may have some potential to establish on field crops, the shorter lifespans and extremely low fectmdities of the F1 adults raised on the six field crops suggests that P＇06 is incapable of rapidly adapting to them. Poor adaptation to field crops may explain, at least partially, why the Q biotype has not established in the US field system.

关键词： Bemisia tabaci host adaptation life history traits population establishment,Q-biotype.

Nitrous Oxide Emission by Agricultural Soils: A Review of Spatial and Temporal Variability for Mitigation

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维普期刊数据库

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Pedosphere 2012年第4期22卷 426-433页

作者： C. HNAUlT A. GROSSEl B. MARY M. ROUSSEl j. lONARD INRA UR 272 Science du Sol Centre de Recherches d'Orléans CS 40001 Ardon 45075 Orléans cedex 2 (France) INRA-Université de Bourgogne UMR 1229 Microbiologie du sol et de l'Environnement 17 rue Sully BP 86510 21065 Dijon cedex (France) INRA US 1158 Agro-Impact Po le du Griffon 180 rue Pierre-Gilles de Gennes 02000 Barenton-Bugny (France)

This short review deals with soils as an important source of the greenhouse gas N2O. The production and consumption of N2O in soils mainly involve biotic processes: the anaerobic process of denitrification and the aerobic process of nitrification. The factors that significantly influence agricultural N2O emissions mainly concern the agricultural practices (N application rate, crop type, fertilizer type) and soil conditions (soil moisture, soil organic C content, soil pH and texture). large variability of N2O fluxes is known to occur both at different spatial and temporal scales. Currently new techniques could help to improve the capture of the spatial variability. Continuous measurement systems with automatic chambers could also help to capture temporal variability and consequently to improve quantification of N2O emissions by soils. Some attempts for mitigating soil N2O emissions, either by modifying agricultural practices or by managing soil microbial functioning taking into account the origin of the soil N2O emission variability, are reviewed.

关键词： agricultural practices fertilization greenhouse gas N2O fluxes soil-atmosphere interface

Interfacial bonding mechanism in Al/coated steel dissimilar refill friction stir spot welds

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j.urnal of Materials Science & Technology 2019年第6期35卷 1027-1038页

作者： Z. Shen Y. Ding j. Chen B. Shalch Amirkhiz j.Z. Wen l. Fu A.P. Gerlich School of Materials Science and Engineering Northwestern Poly technical University Xi'an 710072 China Shanxi Key laboratory of Friction Welding Technologies Northwestern Polytechnical University Xi'an 710072 China State Key laboratory of Solidification Processing Northwestern Poly technical University Xi'an 710072 China Centre of Advance Materials j.ining Department of Mechanical and Mechatronics Engineering University of Waterloo 200 University Ave. Waterloo N2L3G1 Ontario Canada CanmetMATERIAlS Natural Resources Canada Hamilton L8P 0A5 Canada

Defect-free dissimilar Al/zinc coated steel and Al/AlSi coated steel welds were successfully fabricated by refill friction stir spot welding. However, Al alloy and uncoated steel could not be welded under the same welding condition. Al-Zn eutectic layer formed at the Al/zinc coated steel interface showed nonuniformity in thickness and nanoscale intermetallic(IMC) produced was discontinuous. The bonding formation between the Al-Zn layer and the surrounding materials was attributed to a liquid/solid reaction mechanism. Bonding formation at Al alloy and AlSi coated steel interface was attributed to a solid/solid reaction mechanism, as the j.ining process did not involve with melting of base metals or AlSi coating materials. Kissing bond formed at the weld boundary acted as a crack initiation and propagation site,and the present study showed that weld strength of Al 5754/AlSi coated steel was greatly influenced by properties of original IMC layer.

关键词： Refill friction stir spot welding Al alloy Steel Coated materials j.ining mechanism

Microbiology : an introduction / Gerard j. Tortora, Berdell R. Funke, Christine l. Case. 6th ed.

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SIMUlATION-MEASUREMENT INVERSION OF ENVIRONMENT PARAMETERS DURING WElDING

1998年

作者： Gerard j. Tortora Berdell R. Funke Christine l. Case.

Includes index.

ISBN: (纸本)0805385355

Includes index.

关键词： Microbiology.

来源：畅想之星图书光盘版（南... 评论

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畅想之星图书光盘版（南通市图书馆镜像）

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Acta Metallurgica Sinica(English letters) 2005年第6期18卷 763-767页

作者： j. Tao D.Q. li C.l. Fan H.Y. Fang Beij.ng Aeronautical Manufacturing Technology Research Institute Beijing 100024 China State Key laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

The manual selection of environment parameters during welding simulation will bring a significant error to the simulation result of welding temperature field. By a combination of finite element method （FEM） and infrared thermography, these environment parameters were inversed mathematically in place of previous manual selection. First, FEM model of the welding process was constructed, and the temperature field was computed with initial environment parameters. Then, a real welding process was conducted and the temperature field was measured by infrared thermography. last, the simulation and measurement results were compared, and the environment parameters were adj.sted continuously with the genetic algorithm （ GA ） until the simulation matched the measurement best. Parameters according to the best-matched simulation results were considered as the most appropriate parameters.

关键词： environment parameters welding temperature field inversion

AGE STRENGTHENING OF DIFFUSION WElDED j.INT OF Al_2O_(3p)/6061Al COMPOSITE

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Acta Metallurgica Sinica(English letters) 2000年第1期13卷 18-22页

作者： j. T. Niu Y. H. Tian B. Y. li j. j. Xu l.M. liu (National Key laboratory of Advanced welding Production Technology, HIT, Harbin 150001, China)

Tensile strength of diffusion welded j.int of aluminum matrix composite is very low due to its poor weld- *** this paper, solution and age treatments were conducted on the welded j.int of Al2O3p/ 6061Al composite subj.cted to diffusion welding using Gleeble 1500 machine, and ensile strength and microstructure of welded j.int aged at175℃ were measured and analyzed respectively, Results showed that aging precipitation of welded j.int is promoted effectively because of redistribution of reinforcement and a few number of dislocations in the matrix of weld zone resulting from welding pressure,and hence tensile strength of welded j.int is increased significantly after aging treatment.

关键词： aluminum matrix composite diffusion welding aging

Coherent Structures Generated by a Circular j.t Issuing into a Cross laminar Boundary layer

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j.urnal of Thermal Science 1997年第2期6卷 81-85页

作者： l. E. Brizzi j. l. Bousgarbiès E. Foucault laboratoire d’Etudes Aérodynamiques URA 191 Poitiers France laboratoire d’Etudes Aérodynamiques URA 191 (ESIP) Poitiers France

Visualisations by lASER topographies and velocity measurements by lDV have allowed the study of the fiow resulting from the illteraction between a circular j.t and a cross boundary layer. This type of fiow is dominated by the presence of many complex vortices that come from the recombining of the vorticity created in the inj.ction tube and that created aIong the chamber floor.

关键词： j.t vortical structures cross-flow boundary layer

Reservoir stress path and induced seismic anisotropy： results from linking coupled fluid-flow/geomechanical simulation with seismic modelling

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Petroleum Science 2016年第4期13卷 669-684页

作者： D.A.Angus Q.j.Fisher j.M.Segura j.P.Verdon j.-M.Kendall M.Dutko A.j.l.Crook School of Earth and Environment University of LeedsLeeds UK Formerly School of Earth and Environment University of Leeds Leeds UK Department of Earth Sciences University of Bristol BristolUK Rockfield Software ltd. Swansea UK Three Cliffs Geomechanics Swansea UK Repsol Madrid Spain ESG Solutions Kingston Canada

We present a workflow linking coupled fluid-flow and geomechanical simulation with seismic modelling to predict seismic anisotropy induced by non-hydrostatic stress changes. We generate seismic models from coupled simulations to examine the relationship between reservoir geometry, stress path and seismic anisotropy. The results indicate that geometry influences the evolution of stress,which leads to stress-induced seismic anisotropy. Although stress anisotropy is high for the small reservoir, the effect of stress arching and the ability of the side-burden to support the excess load limit the overall change in effective stress and hence seismic anisotropy. For the extensive reservoir, stress anisotropy and induced seismic anisotropy are high. The extensive and elongate reservoirs experience significant compaction, where the inefficiency of the developed stress arching in the side-burden cannot support the excess *** elongate reservoir displays significant stress asymmetry,with seismic anisotropy developing predominantly along the long-edge of the reservoir. We show that the link betweenstress path parameters and seismic anisotropy is complex,where the anisotropic symmetry is controlled not only by model geometry but also the nonlinear rock physics model used. Nevertheless, a workflow has been developed to model seismic anisotropy induced by non-hydrostatic stress changes, allowing field observations of anisotropy to be linked with geomechanical models.

关键词： Coupled fluid-flow/geomechanics Reservoir characterization Seismic anisotropy Stress path

Management and monitoring of public buildings through ICT based systems： Control rules for energy saving with lighting and HVAC services

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Frontiers of Architectural Research 2013年第2期2卷 147-161页

作者： C. Aghemoa j. Virsone G.V. Fracastoro A. Pellegrino l. Blaso j. Savoyat Kevyn j.hannes Politecnico di Torino Energy Depurtment 24 Corso Ducu degli Abruzzi Torino 10129 Ituly CETHIl UMR 5008 Universite Lyon 1 INSA-Lyon Bat. Sudi Cornot 9 rue de 1o physique Villeurbunne Cedex 69621 Frunce

The presented work addresses the topic of energy savings in existing public buildings, when no significant retrofits on buitding envelope or plants can be done and savings can be achieved by designing intelligent ICT-based service to monitor and contro[ environmental conditions, energy loads and plants operation. At the end of 2010 the European Commission, within the Seventh Framework Program, has founded a proj.ct entitled ＂Smart Energy Efficient Middleware for Public Spaces＂（SEEMPubS）. To achieve this goal the proj.ct will implement, in a set of demonstrator buildings, an interoperab[e web-based software and hardware solution for real-time monitoring and control of lighting, heating, ventilation and air conditioning servfces, through both wired and wireless sensor networks. In this paper the first phase of the proj.ct, concerning the selection of the environments to be used as demonstrator and the definition of the control and monitoring strategies to reduce energy consumptions for lighting and air conditioning, are presented.

关键词： Energy efficiency Existing publicbuildings Control strategies Dynamic simulations