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With the growing environmental concerns, biodegradable materials are gaining more importance. Biocomposites which are made from a combination of biological fiber such as flax and hemp together with plastics are finding a good number of applications in day to day life. Flax has good physical and mechanical properties that can be utilized in areas like construction, biomedical & bioproducts and electronics applications. The quality of fiber depends upon various unit operations used in the processing. Drying is one of the most important unit operations which significantly affect the quality of the fiber. The method of drying for removal of moisture from the fiber significantly affects the drying time and quality. In the present study the raw flax fiber was subjected to drying before and after chemical treatment. The physical properties such as; tensile strength, color and structural changes were measured for raw and chemically treated flax fibers.

Engine mounts are an integral part of the vehicle that helps in reducing the vibrations generated from the engine. Engine mounts require a simple yet complicated amalgamation of two very different materials, steel and rubber. Proper adhesion between the two is required to prevent any part failure. Therefore, it becomes important that a comprehensive study is done to understand the mating phenomenon of both. A good linking between rubber and metal substrate is governed by surface pretreatment. Various methodologies such as mechanical and chemical are adopted for the same. This paper aims to present a comparative study as to which surface pretreatment has an edge over other techniques in terms of separation force required to break the bonding between the two parts. The study also presents a cost comparison between the techniques so that the best possible technique can be put to use in the commercial vehicle industry.

In this study a 1-dimensional computational model of a Fe-Zeolite catalyst, implementing conservation of mass, species and energy for both gas and catalyst surface phases has been developed to simulate emissions conversion performance. It is applied to both a fresh catalyst and one that has been aged through exposure to the exhaust system of a Heavy Duty Diesel engine performing in the field for 376K miles. Details of the chemical kinetics associated with the various NOx reduction reactions in the two Fe-Zeolite configurations have been examined and correlated with data from a synthetic gas rig test bench. It was found that the Standard reaction, (4NH3 + 4NO + O2 → 2N2 + 6H2O), which is one of the main reactions for NOx reduction, degraded significantly at the lower temperatures for the aged system.

Research activities in the development of reliable computational models for aftertreatment systems are constantly increasing in the automotive field. These investigations are essential in order to get a complete understanding of the main catalytic processes which clearly have a great impact on tailpipe emissions. In this work, a 1D chemical reaction model to simulate the catalytic activity of a Pd/Rh Three-Way Catalyst (TWC) for a Natural Gas heavy-duty engine is presented. An extensive database of tests carried out with the use of a Synthetic Gas Bench (SGB) has been collected to investigate the methane abatement pathways, linked to the lambda variation and oxide formation on palladium surface. Specific steady-state tests have shown a dynamics of the methane conversion even at fixed λ and temperature conditions, essentially due to the Pd/PdO ratio.

Modern optical diagnostics such as laser induced fluorescence (LIF) offer considerable assistance in developing effective computational capabilities for complex reactive flows. Applications of these selective, spatially-resolved, non-intrusive technologies include model verification, input parameters, and kinetic simplifications for complex calculations. Pertinent examples from our current diagnostics development and flame applications are reviewed with an emphasis on the chemical implications to advanced computational dynamics for engines. Raman, LIF, and chemiluminescence diagnostics are discussed; potential diagnostics applications include fluid mixing, pollutants, knock, flame front location, and temperature measurement.

Individual organic compounds such as hopanes and steranes (originating in lube oil) and selected polycyclic aromatic compounds (PAHs) (generated via combustion) found in particulate emissions from vehicles have proven useful in source apportionment of ambient particulate matter. Currently, little ambient data exists for a majority of these species. Trace organic species in the size-segregated ultrafine (<0.18 µm) and accumulation (0.18-2.5 µm) particulate matter (PM) modes were measured during the winter season next to a busy Southern California freeway with significant (∼20%) diesel traffic. The ultrafine mode was further segregated into 4 size ranges (18-32 nm, 32-56 nm, 56-100 nm, and 100-180nm) with a NanoMOUDI low-pressure cascade impactor sampler. Both ambient and concentrated size-segregated impactor samples were taken in order to collect enough mass for chemical analysis.

The use of environmental friendly lubricants is driven by the emergence of regulations appearing in many countries. The absence of water toxicity is of prime importance. To meet the stringent toxicity requirements, it is important to minimize the amount of additives which are potentially toxic. Base stocks of stable fatty chemicals were selected because the inherent properties closely matched the fluid properties required. This would necessitate the use of a minimum amount of additives. Particular attention has been devoted to the following : low temperature stability, proper viscosity, elastomers swelling, resistance to oxidation and parking brake friction. Complex neopolyol esters based on blends of linear saturated fatty acids are good candidates since they closely match the requirements of hydraulic fluids meeting the ecolabel specification. Comparisons with unsaturated derivatives and synthetic petrochemical esters base oils show their advantages.

One of the major problem in an injection-type agricultural sprayer is measuring and controlling the flow rate of the concentrated chemicals. An electro-mechanical feedback system was designed to control the chemical concentrate flow rate in an injection-type sprayer. The system works well for a fluid with viscosity from 90 to 300 mPa.s and a flow rate from 3 to 20 mL/s (0.1 to 0.68 oz/s). A linear relationship was achieved between the flow rate and metering pump speed. The system also showed a good dynamic performance.

Field Grid Sense is a new system developed for use with a laptop computer to control crop production inputs. The system spatially controls and records field inputs according to regional requirements within the field. Location is identified via the travel lanes formed during field operations. Application rates are predetermined for each field region and stored on computer diskette. The application is adjusted to the assigned value during field operations. This system can be adapted to control/record granular fertilizers, direct chemical injection systems, liquid fertilizers, seed planters, crop yield maps, and/or any field input that needs to be spatially managed. The use of equipment and/or products in this study is not intended to endorse or discredit the manufacturer or product by the researchers, SDSU, and/or SAE. This pulication has been approved by the South Dakota Agricultural Experiment Station as Journal Article No. 2509.

The analysis and description of field generated containment in fluid systems (hydraulic or lubricating oil, fuels, water, etc.) continues to be one of the best indicators of system “health.” The monitoring of the contaminant provides an effective health measure by accurate determination of the contributing factors to system degradation. These include solid particles, water, additive depletion, and a host of resultant synergistic effects such as sludges, gels, etc. Their are many options available for field fluid analysis. Five specific analyses have been found to provide an extensive description of field contaminants. They are particle counting, gravimetric level analysis, proton induced X-ray emission (PIXE) analysis, ferrographic wear debris analysis, and water content analysis. Thorough descriptions of this procedures is provided with detailed application considerations.

Two peristaltic pumps were tested to determine their accuracies in metering three liquid herbicides for injection-type sprayers. To maintain acceptable chemical application accuracy from either pump, recalibration is necessary if the formulation or its temperature changes. An experimental thermal flowmeter was developed and evaluated along with turbine and piston flowmeters. The piston flowmeter had the best linearity and smallest time constant. A system to control the flow rate of the injected chemical is proposed and was simulated to determine its dynamic response. The proposed chemical metering system, coupled with plumbing systems of sprayers used by private and commercial applicators, were simulated to predict chemical application accuracies.

Plasma nitriding has long been used to harden the surfaces of austenitic stainless steels. However, conventional nitriding at temperatures above 500°C normally results in a significant reduction in the corrosion resistance of material, due to the formation of chromium nitride precipitates in the nitrided case and the depletion of free chromium from the substrate. Attempts have been made in the past decade to tackle this problem mainly by lowering the nitriding temperature. It has been established that when the nitriding temperature is sufficiently low, precipitation of chromium nitrides can be suppressed and a hard and corrosion resistant layer, known as S phase, can be produced on austenitic stainless steel surface, achieving combined improvement in wear, fatigue and corrosion resistance. More recently, it has been found that carbon can also be used as the major alloying species to engineer the surfaces of austenitic stainless steels.

Spring steels are the materials most commonly used in suspensions of vehicles and are subject to heavy efforts in terms of load, impact and also under intense fatigue solicitation. Required mechanical performance depends mainly on the chemical composition and heat treatments. Therefore, the aim of the present work was to compare SAE 5160 steel with one Super Clean steel developed in Slovenia. Searches improving mechanical properties of these steels are constantly present in the automotive industry, reducing vehicle weight and maintaining safety. In this scenario, cryogenic treatment in combination with quenching and tempering has shown interesting results in the scientific literature for tool steels and the best results for cryogenics are achieved when the treatment occurs for long duration as 24 hours.

Degradation of the deNOx performance has been found in in-use heavy-duty vehicles with a urea-SCR system in Japan. The causes of the degradation were studied, and two major reasons are suggested here: HC poisoning and deactivation of pre-oxidation catalysts. Hydrocarbons that accumulated on the catalysts inhibited the catalysis. Although they were easily removed by a simple heat treatment, the treatment could only partially recover the original catalytic performance for the deNOx reaction. The unrecovered catalytic activity was found to result from the decrease in conversion of NO to NO2 on the pre-oxidation catalyst. The pre-oxidation catalyst was thus studied in detail by various techniques to reveal the causes of the degradation: Exhaust emission tests for in-use vehicles, effect of heat treatment on the urea-SCR systems, structural changes and chemical changes in active components during the deactivation were systematically investigated.

Low viscosity engine oils are considered a feasible solution for improving fuel economy in internal combustion engines (ICE). So, the aim of this study was to verify experimentally the performance of low viscosity engine oils regarding their degradation process and possible related engine wear, since the use of low viscosity engine oils could imply higher degradation rates and/or unwanted wear performance. Potential higher wear could result in a reduction in life cycle for the ICE, and higher degradation rates would be translated in a reduction of the oil drain period, both of them non-desired effects. In addition, currently limited data are available regarding “real-world” performance of low viscosity engine oils in a real service fleet.

The pneumatic air brake system for heavy commercial trucks is composed by a large number of components, aiming its proper work and compliance with rigorous criteria of vehicular safety. One of those components, present along the whole vehicle, is the air brake tube, ducts which feed valves and reservoirs with compressed air, carrying signals for acting or releasing the brake system. In 2011, due to a lack of butadiene in a global scale, the manufacturing of these tubes was compromised; as this is an important raw material present on the polymer used so far, PA12. This article introduces the methodology of selecting, developing and validating in vehicle an alternative polymer for this application. For this purpose, acceptance criteria have been established through global material specifications, as well as bench tests and vehicular validation requirements.

The demand for higher output performance engines has lead to the increase of PCP (Peak Cylinder Pressure) and more aggressive engine designs for cylinder liners, mainly for new heavy duty engines developments where low cost components are been introduced. Such trends have generated demands to adequate the liner design by improving its material properties by changing its chemical composition, new materials data or even by introducing more accurate casting manufacturing process. Therefore, there is a clear tendency to development more and more alternative solutions that combine a certain technical high-value added and low cost. The most important material properties for cylinder liners are the ultimate tensile strength (UTS) and the fatigue tensile strength. Both parameters confer to the cylinder liners, especially for wet top flanged designs, the ability to survive under high mechanical and thermal load conditions even with reduced wall thickness.

Cyclic oligomers of butylene terephthalate (CBT™)† represent a new chemical route to semi-crystalline thermoplastic polybutylene terephthalate (PBT). The oligomers of interest melt completely at about 150°C to produce a low viscosity fluid that is ideal for wetting and dispersing fibrous fillers and reinforcements thereby enabling the development of composites that were previously not possible when working with high viscosity commercial PBT. Introduction of catalyst to undiluted molten cyclic oligomer leads to rapid ring opening polymerization and the formation of high molecular weight thermoplastic PBT without the generation of volatile organic compounds. The polymer resulting from this polymerization will be hereby referred to as pCBT. Treatment of cyclic oligomers in this fashion results in pCBT thermoplastic resin with a high melting point (230°C) and physical performance similar to that of other commercially available PBT resins.

Site-Specific Crop Management (SSCM) involves use of automated seeders and chemical applicators to make spatially-variable applications to agricultural fields. Soil productivity is spatially variable and thus, SSCM provides an opportunity to reduce total applications of seed and fertilizer without reducing crop yields. Also, more complete crop use of fertilizers with SSCM could reduce the potential for environmental contamination. A key element in SSCM is a Field Information System (FIS) for preparing application maps to control application rates.

The sealing of electrical splices in heavy equipment has become an important element in increasing the life and reliability of both on and off-the-road vehicles. Adhesive lined heat shrink tubing is an effective protective and sealing method for these splices; it protects splices from the mechanical, electrical, chemical and temperature environments that exist in heavy equipment operation. In addition, the tubing meets the production requirements of reproducible installation at production rates and low installed cost. This paper will focus on one heat shrink tubing system which was designed for the sealing of vehicular electrical splices. It will discuss the design requirements, manufacturing methods and installation techniques and mechanisms for this heat shrink tubing system.