Protective Conversion Coating on Mixed-Metal Substrates and Methods Thereof

Mixed-metal automotive vehicle bodies-in-white comprising ferrous metal surfaces, zinc surfaces, aluminum alloy surfaces, and magnesium alloy surfaces are cleaned and immersed in an aqueous bath comprising an adhesion promoter and an aqueous electrocoat bath (the adhesion promoter may be in the electrocoat bath. The adhesion promoter, which may be a cerium salt, is selected to react with each metal in the body surfaces to form an oxide layer that provides corrosion resistance for the surface and adherence for the deposited polymeric paint coating. The body is cathodic in the electrocoat deposition

Loop Coalescing and Scheduling for Barrier MIMD Architectures

Barrier MIMDs are asynchronous Multiple Instruction stream Multiple Data stream architectures capable of parallel execution of variable execution time instructions and arbitrary control flow (e.g., while loops and calls); however, they differ from conventional MlMDs in that the need for run-time synchronization is significantly reduced. This work considers the problem of scheduling nested loop structures on a barrier MIMD. The basic approach employs loop coalescing, a technique for transforming a multiply-nested loop into a single loop. Loop coalescing is extended to nested triangular loops, in which inner loop bounds are functions of outer loop indices. Also, a more efficient scheme to generate the original loop indices from the coalesced index is proposed for the case of constant loop bounds. These results are general, and can be applied to extend previous work using loop coalescing techniques. We concentrate on using loop coalescing for scheduling barrier MIMDs, and show how previous work in loop transformations [Wol89], [Pol88] and linear scheduling theory [ShF88], rShO901 cart be applied to this problem

Hardware Barrier Synchronization: Static Barrier MIMD (SBM)

In this paper, we give the design, and performance analysis, of a new, highly efficient, synchronization mechanism called “Static Barrier MIMD” or “SBM.” Unlike traditional barrier synchronization, the proposed barriers are designed to facilitate the use of static (compile-time) code scheduling for eliminating some synchronizations. For this reason, our barrier hardware is more general than most hardware barrier mechanisms, allowing any subset of the processors to participate in each barrier. Since code scheduling typically operates on fine-grain parallelism, it is also vital that barriers be able to execute in a small number of clock ticks. The SBM is actually only one of two new classes of barrier machines proposed to facilitate static code scheduling; the other architecture is the “Dynamic Barrier MIMD,” or “DBM,” which is described in a companion paper1. The DBM differs from the SBM in that the DBM employs more complex hardware to make the system less dependent on the precision of the static analysis and code scheduling; for example, an SBM cannot efficiently manage simultaneous execution of independent parallel programs, whereas a DBM can

Static Scheduling for Barrier MIMD Architectures

Barrier MIMDs are asynchronous Multiple Instruction stream Multiple Data stream architectures capable of parallel execution of variable-execution-time instructions and arbitrary control flow (e.g., w h ile loops and calls); however, they differ from conventional MIMDs in that the need for run-time synchronization is significantly reduced. Whenever a group of processors within a barrier MIMD encounters a synchronization point (barrier), static timing constraints become precise, hence, conceptual synchronizations between the processors often can be statically resolved with zero cost — as in a SIMD or VLIW and using similar compiler technology. Unlike these machines, however, as execution continues past the synchronization point the accuracy within which the compiler can track the relative timing between processors is reduced. Where this imprecision becomes too large, the compiler simply inserts a synchronization barrier to insure that timing imprecision at that point is zero, and again employs static, implicit synchronization. This paper describes new scheduling and barrier placement algorithms for barrier MIMDs that are based loosely on the list scheduling approach employed for VLIWs [Elli85]. In addition, the experimental results from scheduling more than 3500 synthetic benchmark programs for a parameterized barrier MIMD machine are presented

Multifunctional Cerium-Based Nanomaterials and Methods for Producing the Same

Embodiments relate to a cerium-containing nano-coating composition, the composition including an amorphous matrix including one or more of cerium oxide, cerium hydroxide, and cerium phosphate; and crystalline regions including one or more of crystalline cerium oxide, crystalline cerium hydroxide, and crystalline cerium phosphate. The diameter of each crystalline region is less than about 50 nanometers

Deposition of Cerium-based Conversion Coatings on Aluminum Alloy 380

Cerium-based conversion coatings were deposited on as-cast aluminum alloy 380 substrates by a spontaneous immersion process. In this study, the effects of rinsing temperature prior to immersion in the coating deposition solution were studied with respect to the surface morphology, electrochemical response, and corrosion resistance of the coatings. Panels rinsed at 25 degrees celsius prior to coating had large cracks and holes in the coating. In contrast, panels rinsed at 100 degrees celsius prior to coating had a uniform coating morphology with fewer, smaller cracks. Electrochemical testing revealed that coatings deposited on substrates rinsed at 100 degrees celsius had higher impedance (~80kilo-ohms*cm^2) and lower corrosion current (~0.34nu*A/cm^2) compared to coatings deposited on substrates rinsed at 25 degrees celsius which had 10 kilo-ohms impedance and 2.7 nu*A/cm^2 corrosion current. Finally ASTM B117 salt spray testing showed that rinsing at 100 degrees celsius prior to coating resulted in cerium-based conversion coatings that could resist the formation of salt tails for at least 8 days

Cerium-Based Spontaneous Coating Process for Corrosion Protection of Aluminum Alloys

A cerium-based coating for corrosion resistance is applied by exposing a cleaned aluminum-based component to a corrosion-inhibiting cerium solution containing cerium ions in the presence of an oxidizing agent. The coating deposits spontaneously without an external source of electrons

Process Development for the Formation of Post-Bonding Biorecognition Layers in Microfluidic Biosensors

Formation of the biorecognition layers within microfluidic sensor channels must be done after the completion of the channel structure since these layers cannot withstand the wafer bonding temperature. We propose a new post-bonding immobilization process to prepare the enzyme layers within microfluidic channels of electrochemical biosensors. An array of Pt vertical electrodes is electroplated using a SU-8 mold. The cured SU-8 is then removed by plasma etching to expose the Pt electrode and to define the fluidic channel cavity simultaneously. An array of enzyme posts is formed on the Pt surface by either electropolymerizing or photopolymerizing enzyme precursor solutions injected into the channel. Very little report is available about the reactive ion etching (RIE) of SU-8 that is the most critical step in this process. A systematic investigation on the RIE of SU-8 is conducted to obtain the maximum etch rate (1.2 ¿m/min.) based on different combinations of parameters of CF4 and O2 gas flow, RF power and time

Millimeter Wave Imaging of Corrosion under Paint: Comparison of Two Probes

Critical aircraft structures are susceptible to harsh environmental conditions that cause corrosion of these structural components. It is of great importance to detect corrosion under paint, particularly in its early stages. Millimeter wave nondestructive evaluation methods have shown great potential for detecting corrosion under paint and evaluating its properties. This paper presents and compares the results of using two distinct millimeter wave detection methods; namely a standard single probe and a newly developed differential probe for detecting corrosion under paint

Capacitive Properties and Structure of RuO₂-HfO₂ Films Prepared by Thermal Decomposition Method

Binary RuO2-HfO2 films on Ti substrates were prepared by a thermal decomposition method. cyclic voltammetric and charge/discharge properties of the RuO2-HfO2 electrodes were characterized. It was determined that the incorporation of HfO2 into RuO 2 greatly improved the capacitive properties of the material. The RuO2-HfO2 electrodes showed excellent cyclic stability, with no decay in charge capability during 1000 CV cycles in acidic solution. A nominal content of 50 mol% RuO2 and 50 mol% HfO2 gave the highest specific capacitance of 789.3 F/g (RuO2). The excellent capacitive properties and stability were related to the hydrous amorphous mixed-oxides formed in the film. This work proves that high capacitive performance of RuO2-based electrode materials can be obtained by thermal decomposition, even with the retained chloride in the film