bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Investigation of Carboxylic Acids as Corrosion Inhibitors in Engine Coolant
Authors: Mercer WC 
Published: March 2009

The ability of carboxylic acids to inhibit corrosion in automotive cooling systems was first reported more than 40 years ago. Aromatic carboxylic acids, such as benzoic acid and its derivatives, have been extensively studied and are used in Europe as corrosion inhibitors in commercial coolants. There are few studies of corrosion inhibition by aliphatic carboxylic acids in the open literature. Aliphatic dibasic acids, such as 1,10-decanedioic, and aliphatic monobasic acids, such as octanoic, have recently been proposed as inhibitors in automotive coolant formulations. To date, ASTM performance test data have not been available.
This paper presents a comparison of the performance of selected carboxylic acid coolants with each other and with a traditional North American coolant in laboratory and fleet tests. Protection of cooling system metals, inhibitor depletion, and mixed coolant effects were investigated.
Corrosion Testing for Aluminum Alloy Selection in Automotive Radiators
Authors: Beal RE , El-Bourini R 
Published: March 2009

Durability of aluminum alloy automotive radiators in service depends on the alloy selected and the expected engine coolant environment. The challenge is to find testing methods that correlate with service experiences that allow for comparative evaluation of competing materials without resort to long-term vehicle exposure at initial selection stages. Design, manufacture, and processing affect radiator performance and must be taken into account in corrosion testing. Aluminum alloys AA3003 and AA7072 are used to illustrate the test program.
Electrochemical corrosion test methods were used for screening purposes in alloy selection and corrosion test environment studies. A simulated service test method is used with selected corrosion media to provide accelerated corrosion data in full sized radiators. The importance of relating corrosion test media to ultimate engine coolant use and abuse is covered. Methods have been correlated with field tests to prove the approach used.
Phosphate-Molybdate Supplement Coolant Additives for Heavy Duty Diesel Engines
Authors: Hudgens RD 
Published: March 2009

Supplemental coolant additives (SCAs) are commonly used in heavy duty diesel service. The SCA boosts the performance of the typical antifreeze coolant and replaces additives lost to depletion and coolant dilution.
In the early 1970s chromate based SCA's were phased out because of chromate's toxicity and adverse environmental impact. Borate-nitrite based SCAs replaced the chromates and are widely used today.
This paper describes the development of a third generation phosphate-molybdate additive package. Relative to the borate-nitrite SCAs, the phosphate-molybdate supplemental coolant additive gives better overall aluminum protection. Furthermore if overtreated, it is less likely to cause solder bloom, silicate gelation, and water pump leakage.
Test Strips for Rapid On-Site Analysis of Engine Coolants
Authors: Hemmes PR , Kreiser TH , Valle S , Hercamp RD 
Published: March 2009

This paper reviews the use of test strips for measuring the composition of engine coolants. The tests described include test strips for freezepoint, cylinder lining cavitation corrosion protection, reserve alkalinity, pH, chloride, and mercaptobenzothiazole.
Freezepoint strips work with reasonable accuracy with both ethylene glycol and propylene gly col based coolants. They will also work with mixtures of the two. The strips are shown to work with coolants containing phosphates, borates, or benzoates. Data show that good results can be obtained with new users so that training is minimized.
Strips for liner cavitation protection are described. Good results were obtained with visually read strips for nitrite in the range of 200 to 4000 ppm and for molybdate in the range of 75 to 1500 ppm. A hand-held reflectance meter to read these strips is described. Precision and accuracy data are given. The strips are not sensitive to glycol concentration.
Data are presented for the accuracy of test strips for reserve alkalinity and pH. Test strips for mercaptobenzothiazole are described. A description is also provided of a prototype test for chloride levels in used coolants where the makeup water may have contained salts. In all cases, test strips were found to be accurate, easy-to-use, inexpensive devices useful for routine field monitoring of coolants.
Characterization of Used Engine Coolant by Statistical Analysis
Authors: Woodward SM , Gershun AV 
Published: March 2009

Since the 1950s, the most common choice of engine coolant has been a 50:50 mixture of ethylene glycol and water, with the ethylene glycol containing selected corrosion inhibitors and other additives such as nitrates, silicates, borates, phosphates, tolyltriazole (TTZ), mercaptobenzothiazole (MET), antifoam, molybdates, silicones, dye, surfactant, and alkalinity builder. Manufacturers in Europe and Asia use a different corrosion inhibition technology than those used in North America.
The function of the engine coolant is simple, to remove the heat from the engine and to protect the engine from corrosion and pitting of the metal surfaces. As the coolant accumulates miles or hours in a vehicle cooling system, it develops many different types of problems. With time, the inhibitors deplete, the ethylene glycol degrades, the pH of the coolant solution decreases, and corrosion starts to take place. Silicates can combine with excessive levels of magnesium or calcium, thus losing their ability to protect aluminum; MBT is easily oxidized and results in loss of copper protection; and phosphates can combine with calcium and magnesium to form an insoluble sediment.
A consequence of this chemistry is that the coolant that comes out of an automobile after time and use can be significantly different than what went into it. With the increased emphasis placed on proper waste disposal and recycling of used coolant, it is important to understand what is coming out of the car.
During 1989 and 1990, a statistically valid survey and characterization of used engine coolant was taken from commercial automotive service centers. The purpose of the survey was to characterize the condition of a typical used engine coolant. The samples were evaluated for suspended matter, and analyzed for pH, reserve alkalinity (RA), percent ethylene glycol (EG), diethylene glycol (DEG), propylene glycol (PG); the presence of degradation acids (acetate, glycolate, formate, and ethylenediaminetetraacetate [EDTA]); the level of inhibitors (nitrites, nitrates, TTZ, MET, benzotriazole [BZT], benzoate), oil, chloride, fluoride, sulfate concentrations, and 14 other elements (Al, B, Ca, Cu, Fe, K, Mg, Mo, Na, P, Pb, Si, Sn, Zn) in their soluble and insoluble forms. The samples were also tested following U.S. Environmental Protection Agency (EPA) guidelines to determine if the engine coolant would be considered a hazardous waste.
This paper presents the findings of this survey and shows the variation in the condition of engine coolant taken from automobiles at the time the average consumer decides to change the fluid.
Hydroxylapatite Powders for Implant Coatings
Authors: Tofe AJ , Brewster GA , Bowerman MA , Myers RN , Hurson SM 
Published: March 2009

Dense, porous, resorbable and nonresorbable are all too familiar terms associated with hydroxylapatite (HA) bone grafting materials. While each of the above have their clinical applicability in osseous oral rehabilitation, the HA powder characteristics that ensure optimal plasma spray coatings to implants are distinctly different.
The powder's calcium phosphate phases, the density of the powder, the particle size of the powder and the particle shape and subsequent flow characteristics all can impact upon the quality of the final HA coating. These physical properties coupled to controlling the melt of the powder surface are shown to be related to the quality of HA coatings on implants with respect to crystallinity and bonding strengths. While multiple parameters are important in plasma spraying, control of the powder is the first step toward high-quality coatings.
Techniques for the Characterization and Quality Control of Hydroxyapatite Raw Materials and Coatings
Authors: Flohr KW 
Published: March 2009

The chemical laboratory at a commercial coating company is responsible for characterizing and testing the quality of hydroxyapatite (HA) for both incoming raw material and the applied coatings prior to acceptance of a manufactured lot. Quality control tests of the raw material include measurement of crystallinity of the HA using X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopic (FTIR) methods and chemical analysis of the HA for the proper calcium to phosphorus ratio and for the presence of impurities. The finished coatings undergo all the same tests as the raw material plus an evaluation of adhesion.
Evaluated raw materials have varied widely in composition and properties. Chemical compositions ranged from stoichiometric HA to tricalcium phosphate. Impurities ranged from a probably biologically insignificant presence of magnesium to the presence of over four weight percent of toxic barium and included up to 10 weight percent soluble calcium carbonate. The crystallinity varied from greater than 90% to less than 5%. Variations in crystallinity, the presence of calcium oxide and calcium carbonate, and substitutions of cations other than calcium have the potential of causing variations in the final coating. The reported crystallinity variation was between two different lots from the same supplier. Therefore, it is necessary to continue Quality Control (QC) testing, even for previously approved vendors. The samples with high levels of barium were submitted for use as a less expensive source of HA. This indicates the need to examine carefully all sources of raw materials.
Since the coating used by our company on implants is applied in an inert gas plasma arc, no introduction of foreign cations occurs. However, changes in crystallinity and the transformation from HA to other calcium phosphatephases can occur. The early detection of such changes allows for rapid correction of operator parameters.
In the process of testing HA, a variety of techniques have been developed which may be of general use in the field of HA studies. These include a rapid screening for the presence of carbonate by use of an FTIR, examination of the presence of gross levels of contaminants and simultaneous measurement of grain size and shape by use of a scanning electron microscope with an energy dispersive spectrometer, and working methods to determine the concentration of foreign cations using an atomic absorption spectrophotometer. Additionally, the use of a common vocabulary for HA properties and standardized methods will allow comparison of coatings, not of sales hype.
Calcium Phosphate Type Reference Material: Development, Preparation and Characterization
Authors: Tung MS , Sung P 
Published: March 2009

A proposed calcium hydroxyapatite (HA) reference material has been prepared in large quantity in accordance with the following reaction in solution at 100°C : 5CaO+3H3PO4--Ca5(PO4)3OH+H2O
Stoichiometric HA powder with an atomic Ca/P ratio of 1.67 was obtained as determined by chemical analysis. The X-ray powder diffraction technique was used to evaluate the crystallinity with the measured width at half height of the diffraction peaks. The infrared spectra of the HA powder were obtained to determine the structure and to detect any minor phases. The thermal analysis indicated thermal stability and no decomposition. The thermodynamic solubility product (Ksp) of this HA, expressed as - logKsp (pKsp), was determined to be 57.7 at 25°C. Three additional HA samples prepared by different methods were also characterized and compared.
Changes in Characteristics Arising from Processing and the Effect on In Vitro Stability of Calcium Phosphate Ceramics
Authors: Radin S , Ducheyne P 
Published: March 2009

Numerous studies have shown a three-fold possible effect of calcium phosphate ceramic (CPC) coatings on metallic implants: enhancement of bone tissue growth rates, bonding to bone, and reduction of metal corrosion product release. The two first effects are related to surface reactions of coatings upon implantation. In this study we focus on plasma spray (PS) induced changes in CPC phase compositions and surface areas, and their effect on the in vitro coating stability at physiological pH.
Hydroxyapatite (HA) and β- tricalcium phosphate (β-TCP) PS coatings were obtained from various commercial sources. All of these coatings underwent phase transformations and reduction of specific surface areas due to plasma spray processing. The dissolution rates of all of the PS coatings were found to significantly exceed those of the original HA or β-TCP, in spite of the reduction in specific surface areas. The increase in dissolution rates may be related to plasma spray induced transformations of starting monophases into multiphase coatings containing such components as oxyhydroxyapatite (OHA), α-TCP and tetracalcium phosphate (TTCP).
The multiphase stability depends upon components in the phase mixtures. The in vitro dissolution of monophases and their biphase combinations was studied to assess the influence of each phase component and their combinations. The dissolution rates of the monophase CPCs were found to increase in the order: HA &lt;OHA &lt;β-TCP &lt;α-TCP &lt;TTCP. Dissolution of biphase CPCs, α-TCP/ß-TCP or TTCP/α-TCP, increased with concentration of the more soluble component. Likewise, the dissolution of the PS coatings increased with concentration of the more soluble components. Therefore, PS coatings which contain such metastable components as OHA, α-TCP and TTCP can be expected to be more resorbable than starting HA or ß-TCP.
The Effect of Calcium Phosphate Ceramic Composition and Structure on In Vitro Precipitation Reactions
Authors: Ducheyne P , Radin S 
Published: March 2009

The formation of a biologically equivalent carbonated apatite on the surface of synthetic calcium phosphate ceramics (CPC) may be an important step leading to bonding with bone. Reactions of several single phase CPCs upon immersion into a simulated physiological solution (SPS) with an electrolyte composition of human plasma were determined.The CPCs covered a wide range of stabilities from hydroxyapatites (HA) to metastable tricalcium phosphates (TCP) and tetracalcium phosphate (TTCP). Changes in chemical compositions of SPS and infrared spectral features after CPC immersion were analyzed. New phase formation was observed on all the CPCs. However, kinetics, compositions, and structures of the new phases were significantly different.
The studied CPCs can be characterized by the time to new phase formation in vitro: it was found to increase in the order: not well crystallized (wc) HAS &lt;well crystallized (wc) HAs &lt;α-TCP, TTCP &lt;β-TCP. Only calcium-deficient HA (CDHA) and nwc stoichiometric HAs (s-HA) led to immediate new phase formation. The phase was identified as carbonated apatite. The wc HAs and β-TCP did not elicit carbonated apatite formation within the time frame of the experiment. TTCP transformed intensively to poorly crystallized carbonated apatite after 2 days of immersion.
Dense Hydroxylapatite (HA) and Microporous HA Resorption
Authors: Tofe AJ , Watson BA , Cheung HS 
Published: March 2009

The mechanism of dissolution/resorption of today's bone grafting materials has received minimal attention. While an understanding of this mechanism is of importance to the clinical outcome in osseous regeneration of grafted sites, knowledge of the resorptive process also has direct extrapolation to HA coatings on implants.
In this presentation, the density and porosity of commercially available hydroxylapatite (HA) bone grafting materials were analyzed by scanning electron microscopy (SEM). The calcium phosphate phases and molecular constituents responsible for dissolution/resorption of hydroxylapatite (HA) were analyzed by X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy. The lack of microporosity explains the nonresorptive nature of truly dense HA while the presence of microporosity leads to cell-mediated resorption. The latter was evaluated using an in vitro cell culture model with human fibroblasts. Scanning electron and light microscopy confirmed the endocytosis mechanism for porous HA and illustrated the inhibition of cellular invasion/resorption by dense HA.
A multi-analytical/spectroscopic approach coupled to in vitro cell culture studies provides insight into the dissolution/resorption of HA grafting materials and HA coating on implants.
Comparison of Current Interruption and Electrochemical Impedance Techniques in the Determination of Corrosion Rates of Steel in Concrete
Authors: Berke NS , Shen DF , Sundberg KM 
Published: March 2009

Steel reinforced concrete is a widely used construction material. It is often the material of choice in bridges, parking garages, and marine structures because of its good durability and resistance to corrosion. However, over time, even well designed concrete is susceptible to chloride intrusion from deicing or marine salts or both, resulting in corrosion of embedded steel.
By the time corrosion of steel in concrete is readily noticeable, major repairs are often required. A nondestructive means of determining the corrosion rate of inaccessible steel is thus needed. Electrochemical techniques such as polarization resistance are useful, however resistivities of concrete range from 1000 to greater than 30 000 ohm-cm. Furthermore, reference electrodes are usually greater than 25 mm from the working electrode (rebars). Thus, large ohmic electrolyte resistance is present, even at the low current densities associated with steel in concrete, and must be accounted for to accurately measure corrosion rates.
In this paper we compare the use of current interruption correction for ohmic resistance to an electrochemical impedance measurement at 20 KHz. In general, we find a good correlation between the two techniques, and demonstrate that substantial ohmic resistances are present.
Standards for the Playing Quality of Natural Turf for Association Football
Authors: Canaway PM , Bell MJ , Holmes G , Baker SW 
Published: March 2009

For athletic fields used for soccer (association football), important components of playing quality include: ball rebound resilience, rolling resistance, traction (i.e., grip), and hardness. Other criteria related to, but not direct measures of, playing quality include surface evenness, grass cover, and water infiltration rate.
Standards of playing quality were developed on the basis of comparisons between players' perceptions of surfaces and the results of objective tests taken on the fields within 2 h of matches. Questionnaires were collected from 444 football players at 20 different fields. The fields were tested in the same locations within each field at six 5 by 5-m plots.
The results were used to formulate standards in the form of “preferred” and “acceptable” limits for each component of playing quality. The apparatus, test methods, and proposed standards for association football fields are described.
Standards for the Playing Quality of Artificial Turf for Association Football
Authors: Baker SW 
Published: March 2009

In Britain, over 100 full-sized artificial playing surfaces have been installed for association football (soccer). Performance standards for the playing quality of artificial turf pitches (athletic fields) are required, and the development of different test methods is reviewed. For surfaces for soccer, it is necessary to consider both ball/surface and player/surface interaction. The principal techniques for testing surfaces used in Britain are ball rebound resilience, rolling resistance, traction/friction, sliding resistance, surface hardness (using Stuttgart and Berlin Artificial Athlete instrumentation), and the impact characteristics of a 5.5-kg head striking the turf.
Playing quality standards for soccer on artificial turf surfaces published in 1985 gave performance requirements for three levels of play. Classification to a national standard required ball rebound resilience in the range of 25 to 46%, ball deceleration of 0.45 to 1.5 m/s2, and a traction coefficient of 1.5 to 2.2. These limits are compared with data obtained from six natural turf pitches used by professional clubs covering a wide range of weather and pitch conditions. For ball rebound resilience and traction there was a reasonable comparability of the specified performance limits and the data for natural turf: the interquartile ranges were 31.7 to 44.4% for ball rebound resilience and 1.38 to 1.96 for traction. Some slight modifications to these performance limits are, however, proposed. For natural turf pitches, almost 90% of deceleration values were in the range 0.45 to 1.5 m/s2, but it was evident that values on artificial pitches, after the pile had been compacted by play, were not satisfying the threshold of 0.45 m/s2. Peak deceleration of a 5.5 kg headform after it had been dropped from 1.5 m was lower on natural turf surfaces than on artificial pitches. However, the values on the artificial pitches were comparable with those of safety tiles used as a playground surfacing.
Evaluation of Cyclodextrin Complexes of Pesticides for Use in Minimization of Groundwater Contamination
Authors: Dailey OD , Dowler CC , Glaze NC 
Published: March 2009

Recently, concern over the contamination of groundwater by pesticides has mounted. The cyclodextrin complexes of a number of pesticides most frequently implicated in groundwater contamination have been prepared.
Initial pesticide efficacy studies have been conducted using conventional application technologies with various preemergence herbicides (as both commercial formulations and cyclodextrin complexes) under greenhouse conditions. The leachability and persistence of the newly formulated herbicides in the soil profile were also measured utilizing bioassay indicator crops in the analyses. Cyclodextrin formulations of atrazine and simazine were prepared only under forcing conditions and had very low levels of biological activity. A cyclodextrin formulation of metribuzin was somewhat less active than the commercial formulation, possibly as a result of controlled release properties.
Effect of Sprayer Bounce and Wind Condition on Spray Pattern Displacement of Two Agricultural Nozzles
Authors: Krishnan P , Herrera J , Kemble LJ , Gottfried S 
Published: March 2009

Effect of sprayer bounce and wind velocity on spray pattern displacement (SPD) of two agricultural nozzles were studied using an experimental spray patternator. Tests were conducted at a nozzle pressure of 207 kPa at two wind conditions (C, crosswind velocity of 2.68 m/s; and CH, combination of crosswind velocity and headwind velocity of 2.63 m/s) and at two sprayer bounces (0.2 and 0.4 m amplitude at a frequency of 1 Hz).
Sprayer bounce × wind velocity had significant effect on the SPD values. For both the nozzles, the SPD value for sprayer bounce (0.4 m amplitude) × crosswind velocity × headwind velocity was higher by at least 5 percentage points than that for sprayer bounce (0.4 m amplitude) × crosswind.