Behavior and Design of Axially Compressed Sheathed Wall Studs

The objective of this paper is to summarize efforts in a multi year project dedicated to developing a reliable design method for cold - formed steel wall studs that rely on sheathing for bracing. Testing on single columns with sheathing, and full - scale walls with sheathin g, are summarized. Particular emphasis is placed on the observed limit states given the different sheathing conditions. The sheathing supplies beneficial restraint to the wall studs and the stiffness of this sheathing - based restraint is characterized exper imentally and analytically. A unique application of the Direct Strength Method of design is explored where the sheathing - based restraint is used explicitly in determination of the elastic buckling loads of the wall studs, and then these elastic buckling lo ads are utilized to determine the strength. The test results are compared with the newly proposed design method as well as with previous design methods adopted by the AISI Specification. Good agreement is demonstrated for the new approach both in terms of strength an d limit states prediction

TWO-STROKE ENGINE BEHAVIOR (SMALL CHAINSAW) OPERATING WITH NON-COMMERCIAL FUEL BLENDS AND DIVERSE LUBRICATION

The paper presents results for experimental tests in a two-stroke internal combustions engine operating on commercial fuel (gasoline and ethanol blends), with different proportions in mineral oil for lubrication purposes. Appropriate instrumentation was used to carry out the measurement of the quantities of interest, namely fuel consumption (g/s), angular velocity (rpm) and emissions (CO2 and NOx). The methodology was based on regulations from INMETRO (motor vehicles energy conversion efficiency) and ABNT (testing of internal combustion engines). Results obtained are analyzed and discussed for the fuel consumption versus angular velocity (g/s x rpm) for each combination fuel blend and lubricating oil (quantities). Main findings are that fuel consumption increases non linearly as angular velocity increases and as lubrication lowers, while emissions decreases as angular velocity increases. Lowest fuel consumption and emissions occurred, respectively, for A25/L1:25 and A25/L1:50 (commercial fuel and standard lubrication)

Numerical and Experimental Investigation of Cold-formed Steel Double Angle Members under Compression

This paper presents a numerical and experimental study of double angle members connected by batten plates under concentric and eccentric axial compression. The number of batten plates is varied to study the influence on the nominal axial strength. Numerical analyses are able to accurately predict the behavior and strength found in the experiments, except for long columns under eccentric axial compression where the composite section failed in major-axis flexural buckling. Two design hypotheses are compared to the results obtained: (i) non-composite action (no interaction between angles), with only local, flexural, and flexural-torsional buckling considered; (ii) composite action (full interaction between angles), and only considering local and minor-axis flexural buckling of the pair of angles. The two design hypotheses ignore load eccentricity. Numerical and experimental results for angles connected by bolted batten plates fall in between the design curves defined by methods (i) and (ii), while angles connected by welded batten plates have greater strength than the design curve defined by method (ii). The use of batten plates significantly increases the strength of the system, especially for members under eccentric compression. However, the strength remains constant after a certain number of batten plates are connected, and after a minimum batten plate width is reached

Oxidation reactions of derivatives of cis-octalins promoted by thallium trinitrate (TTN)

The reaction of ten cis-octalins and cis-octalones with thallium trinitrate (TTN) leads to different products, depending mainly on the substitution pattern of the substrate. Functionalized cis-hydrindanes were obtained from the reaction of 1,2,3,4,4a,5,8,8a-octahydro-4a-methylnaphthalene and of 1,2,3,4,4a,5,8,8a-octahydro-4a,7-dimethylnaphthalene with TTN in acetonitrile, whereas a cyclic ether was formed treating 1,2,3,4,4a,5,8,8a-octahydro-6,8a-dimethylnaphthalen-1-ol with TTN in trimethylorthoformate (TMOF).FAPESPCNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES

Exploring the physiological role of transthyretin in glucose metabolism in the liver

Transthyretin (TTR), a 55 kDa evolutionarily conserved protein, presents altered levels in several conditions, including malnutrition, inflammation, diabetes, and Alzheimer’s Disease. It has been shown that TTR is involved in several functions, such as insulin release from pancreatic ß-cells, recovery of blood glucose and glucagon levels of the islets of Langerhans, food intake, and body weight. Here, the role of TTR in hepatic glucose metabolism was explored by studying the levels of glucose in mice with different TTR genetic backgrounds, namely with two copies of the TTR gene, TTR+/+; with only one copy, TTR+/-; and without TTR, TTR-/-. Results showed that TTR haploinsufficiency (TTR+/-) leads to higher glucose in both plasma and in primary hepatocyte culture media and lower expression of the influx glucose transporters, GLUT1, GLUT3, and GLUT4. Further, we showed that TTR haploinsufficiency decreases pyruvate kinase M type (PKM) levels in mice livers, by qRT-PCR, but it does not affect the hepatic production of the studied metabolites, as determined by 1H NMR. Finally, we demonstrated that TTR increases mitochondrial density in HepG2 cells and that TTR insufficiency triggers a higher degree of oxidative phosphorylation in the liver. Altogether, these results indicate that TTR contributes to the homeostasis of glucose by regulating the levels of glucose transporters and PKM enzyme and by protecting against mitochondrial oxidative stress.This work was supported by Norte-01-0145-FEDER-000008-Porto Neurosciences and Neurologic Disease Research Initiative at I3S, and Pest-OE/SAU/UI0215/2014 at UMIB, supported by Norte Portugal Regional Operational Programme (NORTE2020), under the PORTUGAL 2020 Partnership Agreement, by COMPETE 2020—Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, through the European Regional Development Fund (FEDER), by Portuguese funds through FCT—Fundação para a Ciência e a Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior in the framework of the project “Institute for Research and Innovation in Health Sciences” (POCI-01-0145-FEDER-007274), and by a grant from Fundação Millennium bcp. Alemi M was a recipient of fellowship by Norte-01-0145-FEDER-000008. Oliveira  was a recipient of fellowship by Norte-01-0145-FEDER-000008. Cardoso I, Oliveira PF, and Alves MG work under the Investigator FCT Program, which is financed by national funds through the Foundation for Science and Technology and co-financed by the European Social Fund (ESF) through the Human Potential Operational Programme (HPOP), type 4.2—Promotion of Scientific Employment

One-to-one full scale simulations of laser wakefield acceleration using QuickPIC

We use the quasi-static particle-in-cell code QuickPIC to perform full-scale, one-to-one LWFA numerical experiments, with parameters that closely follow current experimental conditions. The propagation of state-of-the-art laser pulses in both preformed and uniform plasma channels is examined. We show that the presence of the channel is important whenever the laser self-modulations do not dominate the propagation. We examine the acceleration of an externally injected electron beam in the wake generated by 10 J laser pulses, showing that by using ten-centimeter-scale plasma channels it is possible to accelerate electrons to more than 4 GeV. A comparison between QuickPIC and 2D OSIRIS is provided. Good qualitative agreement between the two codes is found, but the 2D full PIC simulations fail to predict the correct laser and wakefield amplitudes.Comment: 5 pages, 5 figures, accepted for publication IEEE TPS, Special Issue - Laser & Plasma Accelerators - 8/200

Monosegemented flow potentiometric titration for the determination of chloride in milk and wine

An automated flow potentiometric titration procedure for the determination of chloride in milk and wine exploiting the monosegmented flow approach is described. The flow network was designed based on a six-way solenoid valve, controlled by a microcomputer running software written in VisualBasic 3.0, allowing selection of the titration conditions. An Ag2S tubular electrode selective for Cl- and a conventional Ag/AgCl electrode were employed as indicator and reference, respectively. An algorithm based on the potential difference between two subsequent titrant additions was developed, allowing to reach the end point in less than 10 attempts, with a precision better than 1.0%. The proposed system was evaluated by determining chloride in milk and wine, using a standard AgNO3 solution as titrant. Accuracy was ascertained by comparing the results with those obtained using the AOAC procedure. No significant difference at a 95% confidence level was observed.Este trabalho descreve um procedimento automático em fluxo monossegmentado para titulação potenciométrica aplicado à determinação de cloreto em leite e vinho. O sistema de fluxo foi desenvolvido com base em uma válvula solenóide de 6 vias, controlada por um microcomputador através de um programa escrito em VisualBasic 3.0. Um eletrodo indicador tubular de Ag2S seletivo a Cl- e um eletrodo de referência convencional de Ag/AgCl foram empregados. Um algoritmo baseado na diferença de potencial entre duas adições subsequentes de titulante foi desenvolvido, possibilitando a determinação do ponto final da titulação em, no máximo, 10 tentativas, com uma precisão melhor que 1,0%. O sistema proposto foi avaliado pela determinação de cloreto em leite e vinho, usando uma solução padrão de AgNO3 como titulante. A exatidão foi avaliada comparando-se os resultados com aqueles obtidos pelo método da AOAC, não sendo encontradas diferenças significativas ao nível de confiança de 95%.259264Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

THERMAL PERFORMANCE AND FLAME TEMPERATURES ON LPG RADIAL BURNERS IN DOMESTIC COOKERS

The objective is to investigate radial burners through experimental tests, looking for its thermal performance behavior. Gas burners in domestic cookers operate on LPG, typically with two different geometries and five thermal power conditions. Usually, those thermal equipment lacks information on its whole operating conditions range for higher energy conversion efficiency and lower fuel consumption; it is not pointed out by the manufacturer or by energy efficiency labeling, what could result in a recommendation for widely effective performance. Appropriate instrumentation was used to carry out the measurements and methodology used as a guideline regulations from INMETRO/CONPET, ABNT - Brazilian Technical Standards Normative, and ANP - National Agency of Petroleum, Natural Gas and Biofuels. Experimental measurements and uncertainties are for the following parameters: fuel mass consumption (kg.s-1), test time elapsed (s), temperature (°C), water mass (kg) and flame temperature by K-type thermocouples (quantitative) and a thermal camera (qualitative). Main conclusions are: a) Operating domestic cookers with handle position selector on middle position (TP3) provides almost the same temperature rise as maximum fuel consumption (TP5), i.e., ΔT in the water container; b) Heat is better transferred (Qgas → Qwater) with the handle position selector fully opened (TP5@B1) and just before fully opening (TP4@B2); c) A non-linear behavior occurs for ηThermal, when moving forward the handle position selector; maximum efficiency occurs at fully open (TP5@B2) and middle opening (TP3@B1); d) Higher values for TPexperimental occurs for B2, in comparison to B1, in whole operational condition ranges; differences are mainly due to geometric parameters (ARB2/ARB1~0.82). In general, B2 has a better geometric design; e) Uncertainty analysis indicate values lower than ±3%, proving to be a suitable methodology for the experimental results in this work; f) Flame temperatures are entirely consistent with both, ηThermal and heat energy delivered, reaching higher temperature values at TP4 for both burners; 751.5°C (B1) and 830.7°C (B2)

Graphene field-effect transistor array with integrated electrolytic gates scaled to 200 mm

Ten years have passed since the beginning of graphene research. In this period we have witnessed breakthroughs both in fundamental and applied research. However, the development of graphene devices for mass production has not yet reached the same level of progress. The architecture of graphene field-effect transistors (FET) has not significantly changed, and the integration of devices at the wafer scale has generally not been sought. Currently, whenever an electrolyte-gated FET (EGFET) is used, an external, cumbersome, out-of-plane gate electrode is required. Here, an alternative architecture for graphene EGFET is presented. In this architecture, source, drain, and gate are in the same plane, eliminating the need for an external gate electrode and the use of an additional reservoir to confine the electrolyte inside the transistor active zone. This planar structure with an integrated gate allows for wafer-scale fabrication of high-performance graphene EGFETs, with carrier mobility up to 1800 cm2 V−1 s−1. As a proof-of principle, a chemical sensor was achieved. It is shown that the sensor can discriminate between saline solutions of different concentrations. The proposed architecture will facilitate the mass production of graphene sensors, materializing the potential of previous achievements in fundamental and applied graphene research.N.C.S.Vieira acknowledges a Postdoctoral fellowship at INL from FAPESP – SP/Brazil (2014/01663-6). G. Machado Jr. acknowledges a PhD grant (no. 237630/2012-5) from CNPq – Brazil