Snap-8 mercury corrosion and materials research, volume iii topical report, jun. 1960 - dec. 1962

SNAP-8 materials research - mercury corrosion capsule tests of ferritic alloys for mass transfer, stress corrosion, mode of attack, and mechanical propertie

Hardware-in-the-loop performance analysis of a railway traction system under sensor faults

Fault mode and effects analysis (FMEA) has been used during decades for analysing the effects of faults in different applications. Initially, FMEA based on risk priority numbers provided information about the effects in the system, but during the last years different approaches have been developed to obtain a more robust risk evaluation. The proposed enhanced FMEA can provide the quantitative effects of sensor faults in a railway traction drive, in variables such as torque, current and voltages. In addition to the previous work, quantitative effects on overall performance indicators, such as energy efficiency and comfort, are obtained too. Hardware-in-the-loop (HIL)-based fault injection approach has been used to generate fault scenarios. The test platform is composed of a real-time simulator and a commercial traction control unit for a railway application

The global distribution of leaf chlorophyll content

Leaf chlorophyll is central to the exchange of carbon, water and energy between the biosphere and the atmosphere, and to the functioning of terrestrial ecosystems. This paper presents the first spatially-continuous view of terrestrial leaf chlorophyll content (ChlLeaf) at the global scale. Weekly maps of ChlLeaf were produced from ENVISAT MERIS full resolution (300 m) satellite data using a two-stage physically-based radiative transfer modelling approach. Firstly, leaf-level reflectance was derived from top-of-canopy satellite reflectance observations using 4-Scale and SAIL canopy radiative transfer models for woody and non-woody vegetation, respectively. Secondly, the modelled leaf-level reflectance was input into the PROSPECT leaf-level radiative transfer model to derive ChlLeaf. The ChlLeaf retrieval algorithm was validated using measured ChlLeaf data from 248 sample measurements at 28 field locations, and covering six plant functional types (PFTs). Modelled results show strong relationships with field measurements, particularly for deciduous broadleaf forests (R2 = 0.67; RMSE = 9.25 μg cm-2; p < 0.001), croplands (R2 = 0.41; RMSE = 13.18 μg cm-2; p < 0.001) and evergreen needleleaf forests (R2 = 0.47; RMSE = 10.63 μg cm-2; p < 0.001). When the modelled results from all PFTs were considered together, the overall relationship with measured ChlLeaf remained good (R2 = 0.47, RMSE = 10.79 μg cm-2; p < 0.001). This result is an improvement on the relationship between measured ChlLeaf and a commonly used chlorophyll-sensitive spectral vegetation index; the MERIS Terrestrial Chlorophyll Index (MTCI; R2 = 0.27, p < 0.001). The global maps show large temporal and spatial variability in ChlLeaf, with evergreen broadleaf forests presenting the highest leaf chlorophyll values, with global annual median values of 54.4 μg cm-2. Distinct seasonal ChlLeaf phenologies are also visible, particularly in deciduous plant forms, associated with budburst and crop growth, and leaf senescence. It is anticipated that this global ChlLeaf product will make an important step towards the explicit consideration of leaf-level biochemistry in terrestrial water, energy and carbon cycle modelling

Case Study: A Model Based Systems Engineering (MBSE) Framework for Characterising Transportation Systems Over the Full Life Cycle

Development of transport infrastructure has significant challenges including acquisition lag, phased evolution, multiple disparate stakeholders and environment-specific issues. The Asset Standards Authority (ASA) at TfNSW is introducing MBSE to address these challenges. Instrumental to the introduction is the development of a framework that structures the available data and provides guidance and traceability between the data sets. This framework combines the enterprise-level drivers with the lower level drivers such as standards to outline a generic conceptual design for a transport system. This conceptual design is then used to guide future system development. The outcome is future project information based on greater, enduring understanding of the transport system

Design and Integration for Biodiesel Production from Vegetable Oil via Transesterification Reaction

Introduction Biodiesel is Fatty Acid Methyl Esters (FAME) which is used as a renewable fuel in diesel engines. Extraction of lipid from various flora sources, including Sunflower, Palm, Canola or animal oils, with a Trans-Esterification reaction between alcohol and Triglyceride (TG), leads to production of Biodiesel and Glycerin. The production cost of biodiesel is so important that is now considered as the greatest obstacle during scale-up process. In this research, a model-type of biodiesel production unit (using vegetable oil source), was designed by Aspen HYSYS V7.2 software, then a great deal of the attempt was employed to optimize the overall yield against the processing parameters including: mass and energy consumption load, as well as some technical discussion regarding associated apparatuses. Materials and Methods Process Design The simulation was carried out using Aspen HYSYS V7.2 employing Triolein (as TG), Oleic acid (as Free Fatty Acid (FFA)), and Oleat as biodiesel. Avoiding side-stream reactions as well as trans-esterification, the FFA content was taken to a mere 0.05% (%mass). Feed stream was considered as product of NaOH-catalyzed bi-reactor system operating at 60˚C and 1 atm with the overall conversion of 70% using two series reactors. The ratio of TG to Alcohol is 1:3, however, owing to establish an appropriate reactor performance; this ratio was applied as 1:6 practically. The design was mainly intended to produce 480 m3d-1 biodiesel with mass concentration of 99.65%. Methanol was used in this investigation due to low cost, accessibility and handling considerations. NRTL was taken as the Equation of State (EOS) for the process and should be used PRSV equation in the decanter. Thermal Integration Energy consumption was taken into account as basis of optimization in this study. Table 2 demonstrates the thermal characteristics of all streams consist of source and down-streams, while outlet stream like glycerol streams were neglected to be considered. HR-1, HR-2, HD1-1, HD2-1 and HD3-1 represent cooling water leaving reactors and condensers respectively which input cooling water temperature to utility was 25˚C. Cp also indicates the thermal capacity of each line which can be calculated by multiplying mass flow rate in specific heat capacity. In order to calculate interval temperature, as the next step, the inlet and outlet temperatures of hot flow must be diffracted from the half of minimum approach temperature of exchangers; and the inlet and outlet cold temperatures should be summed with the half of minimum of approach temperature of exchangers. Interval enthalpy can also be calculated using following equation: ΔH interval= ΔT interval [Cp Cold-Cp Hot] Minimum approach temperature (ΔTmin) was also taken as 10°C in the following calculations. Results are shown in Table 3. Results and Discussion Mass Integration Feed stream after reaching 60˚C and 1 atm entered into first reactor. Feed streams reacted in Reac.1, and effluent after cooling to 25˚C flowed to Sep.1. Unreacted oil sent to Reac.1 and effluent of this reactor after cooling to 25 ˚C entered into Sep. 2. Products of Reac.2 including glycerin, methanol, biodiesel and oil were conveyed to Sep.2 (25˚C) for separation of ester and glycerin. The light phase (Ester) was directed to a recycle distillation column (Dist.1) with R=1.5 and 6 trays to obtain extra-pure methanol from biodiesel. Second effluents from Sep.1 and Sep.2 including large quantities of methanol and glycerin were conveyed to second distillation tower (Dist.2) with 5 tray and R=1.5 in order to purify methanol recovery and obtain glycerin purity up to 99.63%. Due to declining expenditure, methanol recycled back to the beginning of process as a feed; while glycerin was sent out to downstream as by-product. Effluent exited from Dist.2 flowed to Sep.3 to improve purity and remove any residual catalysts (NaOH) via HCl reaction. HCl and catalyst entered with identical molar flow and reacted with 95% conversion. The cold and hot energy required for the whole processes were calculated: 18860 kW and 17330 kW respectively. Heat Integration According to Table 3 network required hot and cold energy were found to be zero and 17146.6 kW respectively; where the number “zero” indicates hot streams are able to provide energy needed of cold stream. Care should be taken that the exchanger approach temperature should not be less than the minimum selected approach temperature (ΔTmin). Applying the new system in the process, cold and hot energy reduced to 17018 kW and 16670 kW respectively. According to Figure 2, HEX-8 outlet stream temperature reached 291.8 ˚C after heat transfer. On the other hand, required temperature and heat of distillation tower’s re-boiler were 187.6 ˚C and 1858 kW respectively; therefore this could be used as energy source for the second distillation tower’s re-boilers. The output stream of the 3rd distillation tower virtual exchanger (SHD 3-out) was also important; this stream temperature was 565 ℃ that could be used to provide energy in the 1st distillation column re-boiler. Finally cold energy and hot energy reduced by 19.6% and 38% reaching 15160 kW and 10990 kW respectively. Input and output streams of the process data and the main process flow diagram of the biodiesel process production are shown in table 4 and fig.3. Conclusions Using stream recycle and mass integration methanol, unreacted oil and feed oil consumption reduced up to 60.6%, 70% and 9% respectively. Consequently, due to energy integration by exchanger network, cold and hot energy was reduced by 19.6% and 38% respectively. This integration increases the number of exchangers and pumps power due to the integration target, because the mass and heat integration targets are just reducing the mass and heat consumption. As can be seen from table 5, the number/capacity of used facilities increased in some cases as a result of application of integration method; this item can be optimized depending on economic and operating data and changing the final target to reduce overall cost, for this purpose can be used other methods such as genetic algorithms

Case Study: Customised Enhancement of an MBSE Environment for Transport Infrastructure Projects

Architecture tools have become axiomatic for project success however these tools are designed for tailoring to better meet user\u27s needs. Transport for New South Wales (TfNSW), under the guidance of its Asset Standards Authority, is currently building an architecture framework model to help stakeholders understand and guide transport infrastructure projects in the future so that the delivered systems are more successful. To augment the work of developing the framework, the off-the-shelf tools have been tailored with a series of routines designed to standardize diagrams and structure, validate the model, detect anomalies and distribute data

Activation of mitochondrial KATP channels mediates neuroprotection induced by chronic morphine preconditioning in hippocampal CA-1 neurons following cerebral ischemia

Purpose Pharmacologic preconditioning, through activating several mechanisms and mediators, can increase the tolerance of different tissues against ischemia/reperfusion (I/R) injury. Recent studies have shown that morphine preconditioning has protective effects in different organs, especially in the heart. Nevertheless, its mechanisms are not well elucidated in the brain. The present study aimed to clarify whether the activation of mitochondrial KATP (mKATP) channels in chronic morphine (CM) preconditioning could decrease hippocampus damage following I/R injury. Materials and methods CM preconditioning was performed by the administration of additive doses of morphine for 5 days before I/R injury induction. I/R injury was induced by the occlusion of bilateral common carotid arteries. The possible role of mKATP channels was evaluated by the injection of 5-hydroxydecanoate (5-HD) before I/R injury. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) was performed to detect apoptosis in hippocampal neurons. The expressions of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (BAX) and levels of malondialdehyde (MDA) and catalase (CAT) enzymes were assessed. Results CM attenuated apoptosis in the hippocampal CA1 neurons (P < 0.001 vs I/R), and mKATP channel blocking with 5-HD significantly increased apoptosis (P < 0.001 vs CM + I/R). CM increased CAT activity (P < 0.05 vs I/R) and Bcl-2 protein expression (P < 0.01 vs I/R), while it decreased MDA level (P < 0.05 vs I/R) and BAX protein expression (P < 0.05 vs I/R). Pretreatment with 5-HD abolished all the above-mentioned effects of CM. Conclusions These findings describe novel evidence whereby CM preconditioning in hippocampal CA1 neurons can improve oxidative stress and apoptosis through the activation of mKATP channels and eventually protect the hippocampal tissue against I/R injury. © 2017 Medical University of Bialysto

Activation of mitochondrial KATP channels mediates neuroprotection induced by chronic morphine preconditioning in hippocampal CA-1 neurons following cerebral ischemia

Purpose Pharmacologic preconditioning, through activating several mechanisms and mediators, can increase the tolerance of different tissues against ischemia/reperfusion (I/R) injury. Recent studies have shown that morphine preconditioning has protective effects in different organs, especially in the heart. Nevertheless, its mechanisms are not well elucidated in the brain. The present study aimed to clarify whether the activation of mitochondrial KATP (mKATP) channels in chronic morphine (CM) preconditioning could decrease hippocampus damage following I/R injury. Materials and methods CM preconditioning was performed by the administration of additive doses of morphine for 5 days before I/R injury induction. I/R injury was induced by the occlusion of bilateral common carotid arteries. The possible role of mKATP channels was evaluated by the injection of 5-hydroxydecanoate (5-HD) before I/R injury. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) was performed to detect apoptosis in hippocampal neurons. The expressions of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (BAX) and levels of malondialdehyde (MDA) and catalase (CAT) enzymes were assessed. Results CM attenuated apoptosis in the hippocampal CA1 neurons (P < 0.001 vs I/R), and mKATP channel blocking with 5-HD significantly increased apoptosis (P < 0.001 vs CM + I/R). CM increased CAT activity (P < 0.05 vs I/R) and Bcl-2 protein expression (P < 0.01 vs I/R), while it decreased MDA level (P < 0.05 vs I/R) and BAX protein expression (P < 0.05 vs I/R). Pretreatment with 5-HD abolished all the above-mentioned effects of CM. Conclusions These findings describe novel evidence whereby CM preconditioning in hippocampal CA1 neurons can improve oxidative stress and apoptosis through the activation of mKATP channels and eventually protect the hippocampal tissue against I/R injury. © 2017 Medical University of Bialysto