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Links between global CO_2 variability and climate anomalies of biomes

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science China Earth sciences 2008年第5期51卷 740-747页

作者： peter s. BAKWIN school of Earth and Environmental sciences Queens College City University of New York New York 11367 USA

The global rate of fossil fuel combustion continues to rise, but the amount of CO2 accumulating in the atmosphere has not increased accordingly. The causes for this discrepancy are widely debated. Par- ticularly, the location and drivers for the interannual variability of atmospheric CO2 are highly uncertain. Here we examine links between global atmospheric CO2 growth rate (CGR) and the climate anomalies of biomes based on (1986―1995) global climate data of ten years and accompanying satellite data sets. Our results show that four biomes, the tropical rainforest, tropical savanna, C4 grassland and boreal forest, and their responses to climate anomalies, are the major climate-sensitive CO2 sinks/sources that control the CGR. The nature and magnitude by which these biomes respond to climate anomalies are generally not the same. However, one common influence did emerge from our analysis; the ex- tremely high CGR observed for the one extreme El Nio year was caused by the response of the tropical biomes (rainforest, savanna and C4 grassland) to temperature.

关键词： biomes carbon cycle climate anomaly NDVI El Nio

The influence of various grease compositions and silver nanoparticle additives on electrically induced rolling-element bearing damage

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Friction 2024年第4期12卷 796-811页

作者： samuel BOND Robert L.JACKsON German mills Department of Chemistry and Biochemistry Auburn UniversityAuburn 36849-5412USA Department of Mechanical Engineering Auburn UniversityAuburn 36849-5412USA

Leakage currents accelerate surface degradation of metal contacts via small scale arcing across lubricating films,but recent observations suggest that metallic nanoparticle additives in lubricants may be useful to improve contact *** findings prompted a study that examined electrically induced surface pitting of steel contacts in the presence of several lubricating greases including some containing nanometer-sized colloidal silver(Ag)*** rolling sphere-on-disk experiments were conducted under electro-tribological loads employing polyurea greases derived from mineral and synthetic base oils with and without *** forces and electrical resistance were monitored continuously during the tests;surface changes were characterized by means of optical spectroscopy,stylus profilometry,and scanning electron microscopy(sEM)including compositional analysis using energy dispersive spectroscopy(EDs).The observations demonstrate that surface pitting induced by arcing occurs mainly at the points were the rolling motion changes direction and that eroded metal is deposited along the wear ***-sized pits are formed which contain carbon and oxygen indicating that arcing causes decomposition of the hydrocarbon *** findings indicate a significant inhibition of pitting is induced by the Ag nanoparticles;some greases containing other additives exhibit a similar,although less pronounced,effect.

关键词： electric motor bearings wheel bearings electric vehicles arcing electrically induced bearing damage pitting leakage current stray current

Re-evaluation of Rostraria bierii Tokioka,1970(Annelida)from seto,Japan as a magelonid,with a review of the Magelonidae of the western Pacific

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Acta Oceanologica sinica 2022年第3期41卷 61-69页

作者： Mortimer Kate mills Kimberley Gil Joao Department of Natural sciences Amgueddfa Cymru-National Museum WalesCathays ParkCardiff CF103NPWalesUK school of Earth and Environmental sciences Cardiff UniversityCardiff CF103ATWalesUK Centre of Marine sciences(CCMAR) University of AlgarveCampus de GambelasFaro 8005-139Portugal

The identity of Rostraria bierii,originally described as a larval amphinomid from Cape setozaki,Pacific coast of Japan,is *** on the original description and illustrations,reinterpretations conclude the“larva”to represent a partial juvenile or adult magelonid specimen,broken after the first *** original figures are compared with several known magelonid species to justify the new *** authors suggest the supposed amphinomid larva is a Magelonidae taxon *** identity of the species is discussed in line with the current knowledge of the Magelonidae in the western Pacific and a key to all known species within the region is provided to aid *** gaps in our taxonomic knowledge of the Magelonidae of the western Pacific are highlighted and discussed.

关键词： Polychaeta Amphinomida Magelonidae Magelona Octomagelona western Pacific identification key Cape setozaki

Generalized stacking fault energy surface mismatch and dislocation transformation

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npj Computational Materials 2021年第1期7卷 1863-1870页

作者： Longsheng Feng Michael J.mills Yunzhi Wang Department of Materials science and Engineering The Ohio State University2041 College RoadColumbusOH 43210USA

Even though the fundamental rules governing dislocation activities have been well established in the past century,we report a phenomenon,dislocation transformation,governed by the generalized-stacking-fault energy surface mismatch(GsF mismatch for short)between two co-existing *** carrying out ab-initio-informed microscopic phase-field simulations,we demonstrate that the GsF mismatch between a high symmetry matrix phase and a low symmetry precipitate phase can transform an array of identical full dislocations in the matrix into an array of two different types of full dislocations when they shear through the *** precipitates serve as a passive shockley partial source,creating new shockley partial dislocations that are neither the ones from the dissociation of the full *** phenomenon enriches our fundamental understanding of partial dislocation nucleation and dislocation-precipitate interactions,offering additional opportunities to tailor work-hardening and twinning processes in alloys strengthened by low-symmetry precipitate phases.

关键词： transformation dislocation mismatch

Is the disease course predictable in inflammatory bowel diseases?

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World Journal of Gastroenterology 2010年第21期16卷 2591-2599页

作者： peter Laszlo Lakatos Lajos s Kiss 1st Department of Medicine Semmelweis UniversityH-1083 BudapestKoranyi S 2AHungary

During the course of the disease,most patients with Crohn's disease(CD) may eventually develop a stricturing or a perforating complication,and a significant number of patients with both CD and ulcerative colitis will undergo *** recent years,research has focused on the determination of factors important in the prediction of disease course in inflammatory bowel diseases to improve stratification of patients,identify individual patient profiles,including clinical,laboratory and molecular markers,which hopefully will allow physicians to choose the most appropriate management in terms of therapy and intensity of *** review summarizes the available evidence on clinical,endoscopic variables and biomarkers in the prediction of short and long-term outcome in patients with inflammatory bowel diseases.

关键词： Inflammatory bowel disease Crohn’s disease Ulcerative colitis Disease course Predictive markers Clinical serology Genetics

Current status of thiopurine analogues in the treatment in Crohn's disease

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World Journal of Gastroenterology 2011年第39期17卷 4372-4381页

作者： peter Laszlo Lakatos Lajos s Kiss 1st Department of Medicine Semmelweis University

In the last decades,with the development of biological therapy,the treatment paradigms in patients with Crohn＇s disease have continuously *** studies focusing on the optimal use of both traditional immunosuppressants and biological therapy have been published,investigating conventional,accelerated stepup and top-down *** addition,much emphasis has been placed in recent years on the de-termination of important predictive factors that could enable early patient stratification,which would lead to a tailored management *** this review,the authors try to highlight new evidence on the optimal timing,benefits,and risks of immunosupressants alone,or in combination,in patients with Crohn＇s disease.

关键词： Crohn's disease Immunosuppressives Azathioprine Thiopurine methyltrans ferase Biologicals

Kinematics and Dynamics of Deployable structures with scissor-Like-Elements Based on screw Theory

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Chinese Journal of Mechanical Engineering 2014年第4期27卷 655-662页

作者： sUN Yuantao WANG sanmin mills James K ZHI Changjian school of Mechanical Engineering Northwestern Polytechnical University Department of Mechanical and Industrial Engineering University of Toronto5 King's College Rd.Toronto OntarioCanada

Because the deployable structures are complex multi-loop structures and methods of derivation which lead to simpler kinematic and dynamic equations of motion are the subject of research effort, the kinematics and dynamics of deployable structures with scissor-like-elements are presented based on screw theory and the principle of virtual work respectively. According to the geometric characteristic of the deployable structure examined, the basic structural unit is the common scissor-like-element（sLE）. First, a spatial deployable structure, comprised of three sLEs, is defined, and the constraint topology graph is obtained. The equations of motion are then derived based on screw theory and the geometric nature of scissor elements. second, to develop the dynamics of the whole deployable structure, the local coordinates of the sLEs and the Jacobian matrices of the center of mass of the deployable structure are derived. Then, the equivalent forces are assembled and added in the equations of motion based on the principle of virtual work. Finally, dynamic behavior and unfolded process of the deployable structure are simulated. Its figures of velocity, acceleration and input torque are obtained based on the simulate results. screw theory not only provides an efficient solution formulation and theory guidance for complex multi-closed loop deployable structures, but also extends the method to solve dynamics of deployable structures. As an efficient mathematical tool, the simper equations of motion are derived based on screw theory.

关键词： scissor-like-element screw theory kinematics dynamics the principle of virtual work

Effect of Osmotic stress in Early stages of Ontogenesis on Root Respiration, Growth, sugar Content,and Cell Injury in Maize seedlings Differing in Drought sensitivity

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Journal of Integrative Plant Biology 2006年第7期48卷 814-822页

作者： Lukás, Kolarovic Miroslava Luxová peter Valentovic Institute of Botany Slovak Academy of Sciences Dubravská cesta 14 Bratislava 84523 Slovakia

Cultivars of maize （Zea mays L.） with different sensitivity to drought were exposed to 0.3 mol/L sorbitol （-1.4 MPa water potential） for 24 h. Exposure to water deficiency significantly reduced the growth of both shoots （coleoptile and hypocotyl） and roots. shoot growth was inhibited more than the growth of roots. Osmotic stress enhanced accumulation of soluble sugars. Electrolyte leakage, a cell injury index, was slightly increased after 0.3 mol/L sorbitoh Respiration was measured in the presence and absence of 2,6-dlchloro-phenol indophenoh 2,6-Dichloro-phenol indophenol did not influence respiration rates, because statistically equal results were observed under both conditions. Total respiration （VT） decreased after osmoticum treatment. There were no significant differences in the VT among the cultlvars analysed. The decrease In VT was caused by a decline In the activities and capacities of both cytochrome （Vcyt, Vcyt） and alternative pathway （Valt, Valt） of respiration. A high residual respiration （Vres） was observed, up to 27% of total uninhibited respiration. The result of uncoupler use clearly indicated that coupling was maintained after 24 h of osmotic stress. The recovery of the respiration rate was comparable with that of non-stressed control rates. According to these observations, no possible mltochondrial damage is expected. Water deficiency did not induce a stimulation of the alternative oxidase, so we assume that the stimulation of the alternative pathway is not related to drought stress resistance; rather, the function of the alternative pathway is to balance carbon metabolism and electron transport in a response to a changing environment.

关键词： alternative oxidase (AOX) alternative respiration 2,6-dichloro-phenol indophenol (DCPIP) maize osmotic stress sugars uncoupler.

solidification and crystallization properties of CaO-siO_2-Na_2O based mold fluxes

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 261-264页

作者： sheng-ping He Qian Wang Dan Xie Chu-shao Xu Z.s. Li K.C. mills Chongqing Key Laboratory of Metallurgical Engineering College of Materials Science and Engineering Chongqing University Chongqing 400044 China Department of Materials Imperial College London London SW72AZ UK

Crystallization properties play an important role in keeping a smooth running of continuous casting process and high surface quality of cast strands. To reduce fluorine pollution in slag, a new type of CaO-siO2-Na2O （CsN） based mold flux was studied. The solidification and crystallization properties, including crystallization temperature, crystallization ratio and solidification mineragraphy, were measured, which were compared with the CaO-siO2-CaF2 （GF） mold flux. The results show that the crystallization performance is equal to the high fluoride mold powder and CsN can be used for peritectic steel grades sensitive to longitudinal cracking in continuous casting.

关键词： mold fluxes crystallization properties mineragraphy peritectic steel