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Fluorescence can be used to measure and visualize the activity of herbicides that inhibit the photosynthesis. Glyphosate, although not acting primarily on the photosystems, appears to increase fluorescence of plants. We investigated whether fluorescence technology is a useful tool to both quantify and image of the performance of different adjuvants for glyphosate. A red laser beam providing equipment is used to scan black nightshade plants at a low and high light intensity. A cooled, integrating 16 bit CCD camera is used to record the fluorescence during the low level (Fo) and high level scan (Fm). The relative increase of fluorescence expressed as [(Fm—Fo)/Fm] 100 % is calculated and color images are produced. Glyphosate was applied at two suboptimal application rates of 16.9 and 33.8 g ae/ha at 200 L/ha. Both the influence of glyphosate rate and the influence of added adjuvants were obvious. The fluorescence data 30 h after treatment demonstrated that the adjuvants HM9121-A and HM9110 performed better than AMS, HM9541-A, HM9910, or HM2005-B. This observation was consistent over the next three observations (54, 78, and 102 h). The fluorescence data after 72 h correlated (R2=0.82; logarithmic regression) with the fresh weight reduction caused by the glyphosate treatments. The adjuvants HM 9121-A and HM9110 performed the best and the adjuvant HM9541-A had little effect on glyphosate performance. Both imaging and fresh weight data indicate that HM 9121-A performs somewhat better than HM9110.

Oxygen distribution in the rod cladding tubes during a Loss of Coolant Accident (LOCA) situation is known to play a key role regarding the post-quench mechanical properties of fuel rods. Analyticalsolutions of the diffusion equations in the complex multilayer and multiphase systems describing thecladding material tube during high temperature oxidation are limited to stationary isothermal conditions. To address the problem of non-stationary transient LOCA situations, a numerical tool (named DIFFOX) hasbeen developed. In the first part, the main assumptions and main features of the code are described. In parallel to the code development, an experimental program has been launched to provide a validation database as well as to input data for improvement of the code models. Zircaloy-4 cladding samples have been pre-oxidized at low temperature then vacuum annealed or steam oxidized at high temperature. Oxygen distribution profiles are investigated by Electron Probe Microanalysis. The ability of the code to describe the chemical reduction of the pre-oxide layer and oxygen diffusion into the metal during high temperature annealing is demonstrated. Regarding high temperature steam oxidation, the pre-oxide layers are observed to be either protective or not on a same given sample. While a good code to experimental data agreement is obtained in the first case, the growing of a high temperature oxide underneath the pre-oxide is not well reproduced by the code. The effect of hydrogen has also been investigated by performing small scale oxidation tests on 600 wppm hydrogen charged Zy-4 cladding. Samples have been long-term annealed for homogenization after oxidation. The main purpose of these experiments is to provide quantitative data on the modification of the α/α+β and α+β/β transus of the Zy4-O pseudo binary phase diagram induced by the presence of hydrogen. A variation of the transus locations deduced from these experiments is proposed. Copyright © 2011 by ASTM International.

The highly hardened surface layers obtained from a TiN-physical vapor deposition (PVD) coating and a treatment that leads to a surface carbon enrichment, applied to American Iron and Steel Institute (AISI) 304, 316, and 316L stainless steels, have been characterized. The metallographic analyses have revealed a depth of about 2.5 μm for the TiN-PVD treatment (1150 HV) and of between 30 and 40 μm for the carbon enrichment (1000–1150 HV), depending on the steel composition. The molybdenum enhancing carbon diffusion is also discussed. The X-ray diffraction analysis has shown an increase in the lattice parameter, subsequent to insertion of the carbon interstitial element, a reduced Fe5C2 Hagg carbide precipitation (mainly on AISI 304 samples), and high compressive stresses. The carbon profiles, obtained on carbon enriched samples through microprobe analysis, have been related to the HV profiles.

Stainless steels are widely used in chemical and other industries due to their corrosion resistance. However, because of their low hardness and wear properties, their applications are limited. Many attempts have been made to increase the surface hardness of these materials by using plasma techniques. Plasma nitriding is distinguished by its effectiveness, and for presenting a relatively low cost and being a clean process, producing hard surface layers on stainless steels. Aiming to verify the influence of the temperature and pressure on the modified resultant layers, samples of AISI 316 and 409 stainless steels were plasma nitrided in two different temperatures (450 and 500°C) and pressures of 400, 500, and 600 Pa for 5 h. After the nitriding treatment, the layers were analyzed by means of optical microscopy and wear tests. Wear tests were conducted in a fixed-ball micro-wear machine without lubrication. After the plasma nitriding treatment on AISI 316 and 409 samples, homogeneous and continuous layers were produced and their thicknesses increased as the temperature increased and as the pressure decreased. The nitriding treatment on the AISI 316 steel resulted on the formation of expanded austenite layers at 450°C and chromium nitrides (CrN and Cr2N) phases at 500°C. The nitriding treatment on AISI 409 yielded the formation of similar layers for both treatment temperatures; these layers constituted mainly chromium (Cr2N) and iron (Fe2N, Fe3N, and Fe4N) nitrides. After the nitriding treatment, the AISI 316 steel sample presented higher wear resistance for lower temperature and pressure values. The increase on layer fragility, for higher temperature and pressure values, can be responsible for this inverse tendency. The wear resistance of the nitrided AISI 409 sample followed a logic tendency: the harder the layer, the better the performance, i.e., the performance was improved with the increase in both the temperature and pressure.

Promoted ignition testing [1–3] is used to determine the relative flammability of metal rods in oxygen-enriched atmospheres. In these tests, a promoter is used to ignite each metal rod to start the sample burning. Experiments were performed to better understand the promoted ignition test by obtaining insight into the effect a burning promoter has on the preheating of a test sample. Test samples of several metallic materials were prepared and coupled to fast-responding thermocouples along their length. Various ignition promoters were used to ignite the test samples. The thermocouple measurements and test video were synchronized to determine temperature increase with respect to time and length along each test sample. A recommended length of test sample that must be consumed to be considered a flammable material was determined based on the preheated zone measured from these tests. This length was determined to be 30 mm (1.18 in.). Validation of this length and its rationale are presented.

The detailing of wall-window interfaces and the consequences of defective installation of windows is an on-going concern in North America. This manuscript concerns laboratory evaluation of the water leakage performance of a select set of window-wall interface details. The details were for windows with mounting flanges installed in wood-frame walls sheathed with rigid extruded polystyrene foam. The tests were performed on a single full scale test assembly in which two identical windows were installed by two similar but nonetheless different means. Each detail included a sill pan intended to collect water that gained entry into the assembly and thus was designed to be robust (tolerant of flaws). Tests were performed over a series of different water loading (spray) rates, and over a series of different air pressure differentials at each spray rate. Air leakage rates through the window opening were monitored; they were controlled by a unique methodology. Leakage paths were introduced in the window frames and these paths were alternatively blocked or opened to permit evaluation of the performance of the installation details under two different assumed conditions of window leakage. Air pressure distribution within the assemblies was monitored during spray testing. The wall assembly were designed to permit observation of water entry in it, and to allow measurement of water entry to, or drainage from, various locations within the assembly. Results on water entry and management for the two wall-window interface configurations are given and effectiveness of the details is discussed.

International audience; It is now well acknowledged that, after a prototypical loss of coolant accident (LOCA) transient, the resultant mechanical properties of fuel cladding tubes depend strongly on the oxygen content of the residual prior-β layer, as this phase is the only metallic part of the high-temperature oxidized cladding that may show some residual ductility. The aim of this study is to obtain relevant information on the evolution of the mechanical properties, on the one hand, of the prior-β structure as a function of the oxygen content, assuming that there is a critical oxygen content that leads to a ductile-to-brittle failure mode transition at low testing temperatures (20–135°C); and on the other hand, of the α(O) structure as a function of the oxygen content. Sheets of Zircaloy-4, 1 to 3 mm thick, and M5® advanced alloys from AREVA NP have been studied. To obtain different oxygen contents, they were oxidized at high temperature and then annealed under vacuum in order to reduce the oxide layer. Systematic post-treatment measurements of the oxygen concentration and of its homogeneity within the sheet thickness were performed. The different prior-β and α(O) structures thus obtained have homogeneous oxygen content between ∼0.14 wt. % and 0.9 wt. % and ∼2 wt. % and 7 wt. %, respectively. Such oxygen concentration ranges cover the solubility values that are expected in the β phase and in the α(O) phase at high temperatures typical of LOCA transients. Detailed microstructure investigations were subsequently performed on the prior-β structures since it is considered to be the most important layer when regarding the post-quench mechanical behavior of the material. Continuous cooling temperature (CCT) phase diagrams as a function of the oxygen content were established to correctly interpret the results. Electron backscattered diffraction (EBSD) analysis has then allowed the crystallographic orientations and the morphology of prior-β phase sub-grains to be determined. For each considered prior-β grain, it was possible to interpret the data by taking into account the “Bürgers” crystallographic relationship between the parent β phase and the resultant α phase. Complementary electron probe microanalysis (EPMA) was also used. These last experiments have shown a spatial fluctuation of the oxygen content within the microstructure that depends both on the nominal oxygen content and on the cooling rate. Nanohardness measurements were also performed and correlated with this oxygen spatial partition. These measurements proved to be useful for the understanding of the tensile macroscopic mechanical behavior. Finally, on the one hand, tensile tests were performed on prior-β phase at testing temperatures ranging from −100°C up to 260°C. The ductile-to-brittle temperature transition and the mechanical constitutive laws as a function of the oxygen content were then described. These tests show the existence of a ductile-to-brittle failure mode transition at 20°C for a critical oxygen concentration of ∼0.5 wt. %. A detailed fractographic analysis was performed to assess the failure mechanism. On the other hand, four-point bending tests were conducted on α(O) phase at 25°C and 135°C in order to obtain behavior laws. Preliminary finite element calculations were performed to simulate ring compression tests carried out on multi-layered high-temperature oxidized cladding tubes.

An overview is given of practices for “retrospective” dosimetry based on extraction and counting of niobium and manganese present in typical pressure vessel materials. The main problem of counting structural materials is the overwhelming presence of the nuclide 60Co in the gamma-ray spectra of irradiated materials. Chemical separation of niobium and manganese is needed to determine the induced 93Nbm and 54Mn activities. Procedures have been developed for retrospective dosimetry applicable at normally equipped radiochemical laboratories. Chemical separation procedures have been applied followed by determination of the amount of niobium in dissolution after separation. Special attention has been given to the accurate counting of the very weak X rays of 93Nbm. Different techniques have been applied. Advantages, disadvantages, and the accuracy that can be achieved are discussed. Special attention has been given to the maximum accuracy that can be reached and the minimum amount of niobium that has to be collected to reach this accuracy.

The lifetime of thin-walled catalyst-carrying foils is directly linked to the overall amount of aluminum present in the base alloy. Ferritic stainless steel containing more than 7 wt. % of Al represents an interesting material for the production of substrates in catalytic converters because of its good corrosion resistance at high temperature. Despite that, the considerable brittleness of the alloy makes production by means of traditional metallurgical processes difficult. Enriching the steel surface with aluminum avoids these problems and due to the high superficial aluminum concentration, enhances the Al2O3 scale formation in the early stages of the oxidation process. Among several techniques, the co-rolling process appears to be a promising technology for enriching ferritic stainless steel surfaces with aluminum without affecting the structural and mechanical properties of the substrate. This process involves cold rolling the annealed AISI 430 ferritic stainless steel together with aluminum foil to form an Al-steel-Al sandwich. After a preoxidation treatment the resultant assemblies were subjected to cyclic oxidation in air. Their oxidation behavior was then characterized by the weight gain versus the number of cycle curves. Oxides were examined by SEM and the phases were identified by X-ray diffraction (XRD). The results highlight that in the lower range of temperatures (T

Transgenic mouse assays, such as MutaMouse, provide a method to predict the potential target organ carcinogenicity of chemical compounds. As part of a validation study, the effects of the direct-acting mutagens, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and 1-chloromethyl-pyrene (CMP), were investigated for gene mutation in the tissues of MutaMice after a single oral or topical exposure. MNNG (50 or 100 mg/kg) or CMP (25 or 50 mg/kg) were administered as a single oral dose and the mice killed after 3, 7 or 10 days. Mutation frequencies were determined in stomach DNA from both MNNG and CMP-treated animals and in liver DNA from the MNNG-treated animals only. The results, although obtained from a limited number of animals, consistently showed that MNNG increased the mutation frequency in stomach DNA, but not apparently in liver DNA, at each exposure time; no clear increase in mutation frequency was seen in the stomach DNA of CMP-treated animals. Also, MNNG (250 or 500 micrograms) or CMP (5 or 10 micrograms) in acetone were applied as a single dose to the shorn skin of mice 7, 14 or 21 days prior to death. A positive control group was similarly given dimethyl-benz[a]anthracene (DMBA, 40 micrograms) and sacrificed after 14 days. Mutation frequencies were determined in the skin DNA extracted from all animals and in the stomach DNA from MNNG-painted animals only. The results, again obtained from a limited number of animals, clearly showed that all test compounds consistently increased the mutation frequency of skin DNA and that these increases were far greater in the DMBA- and MNNG-treated mice than the CMP-treated mice. No apparent increases were seen in the stomach DNA from the MNNG-painted mice.

Transgenic mouse assays, such as Muta Mouse, provide a method to predict the potential target organ carcinogenicity of chemical compounds. As part of a validation study, 2-acetylaminofluorene was administered as a single oral dose of either 50 or 100 mg/kg. The mice were killed 3, 7, 14, 28, 56 or 112 days after this single treatment. Mutation frequencies were determined in liver DNA. The results showed that a mutagenic response was observed in the mice treated at the highest dose (100 mg/kg) and this increase was expressed from 28 up to 112 days after the single exposure.

Until now, most of the detailed characterizations of the M5 corrosion behaviour were performed under standard PWR operating conditions, under moderate Li content and moderate temperature of the primary coolant. In this study, in addition to these standard conditions, two demanding operating conditions were explored: increased Li chemistry and elevated temperature. The objective is to establish whether these more demanding conditions have an impact on the structure of the oxide layers formed, on Nb, Li and B contents in these layers and on Hydrogen pickup of the cladding. The structure of oxide layers was studied by microscopy, the Nb content and distribution by Electron Probe Micro Analysis, the Li and B contents and distributions by Nuclear Reaction Analysis and the hydrogen pickup by gas extraction. It was observed that the stability of the corrosion behaviour of M5 is not affected by increased Li or elevated temperature conditions. The hydrogen pickup fraction of M5 is not modified by increased Li conditions or by irradiation temperature with measured contents (

In vitro wear tests results and 2-year follow up radiographic analyses of implanted fixed- and mobile-bearing LPS Flex knees are compared. The two knee designs use gamma-sterilized GUR 1050 ultra high molecular weight polyethylene (UHMWPE) patellae and tibial inserts, and the same CoCrMo alloy (ASTM F 75) femoral components. The in vitro wear tests were performed on six fixed- and six mobile-bearing knee implants using modified ISO 14243-3 load and kinematic waveforms. Tests were conducted at a frequency of 1 Hz for 5 × 106 cycles (Mc) in bovine serum lubricant. Two year follow up radiographic analyses were performed on 341 patients implanted with 173 mobile- and 168 fixed-bearing implants. Average accumulative in vitro polyethylene wear rates of the mobile- and fixed-bearing knees were 19.9 ± 5.1 mg/Mc and 14.2 ± 2.1 mg/Mc, respectively. There is no statistically significant difference in the wear rates of both devices (p > 0.05, Mann–Whitney test). Overall survivorship at two years with revision for any reason as the endpoint was 99.3 % for the mobile group and 100 % in the fixed group. There was no evidence of tibial, femoral, or patella bone loss at the two year follow up. The mean active range of motion increased from 110.8° to 127.0° in the mobile- bearing group and from 110.7° to 127.2° in the fixed-bearing one. Overall, radiographic evaluation showed similar performance of both devices.

This work presents a survey of the mechanical properties (hardness and modulus of elasticity), tribology (friction coefficient and wear rate), and metallography analysis of the ASTM A283 carbon steel subjected to the sulphidation process. The samples were submitted to the sulphidation process at an atmosphere with 0.2 % H2S (hydrogen sulphide) and 98.8 % H2 (hydrogen gas) for different time (5,10, 20, 60, and 120 min)at 300°C. After exposure to sulphidation environment the growth kinetics was analyzed. The results obtained with the sulphidation process indicate that the ASTM A283 carbon steel follows a parabolic law with a equilibrium constant in terms of pressure Kp = 1.47· × 10−12 g2 cm−4 s−1 for the material analyzed. The experimental results for the hardness and surface modulus of the samples show an increase in the values for the sulphide sample for 120 min.

Dynamic stabilization systems may be subject to anterior-posterior shear loading. However, there is no standard method established for testing a vertebrectomy model in anterior-posterior translation (as may be seen with dynamic spondylolisthesis). A new anterior-posterior shear fatigue test was devised to test one such dynamic stabilization system in anterior-posterior translation. Similar to ASTMF1717 assemblies, constructs were assembled so that screws were placed in ultra high molecular weight polyethylene blocks to attach to the test fixture. The test setup ensures that the entire shear load is transmitted by the implant system. Unlike ASTMF1717 assemblies, the blocks were rotated 180 deg from each other to facilitate loading in the test frame. This configuration is modified from an expected in vivo usage. However, the resultant load vectors are appropriately similar to the shear loads being simulated. The constructs include polymeric components and thus were tested at body temperature in a fluid bath. The blocks were moved ±5 mm with respect to each other. The constructs were cycled at 2 Hz for a minimum of 5 × 106 cycles. The constructs successfully survived 10 × 106 cycles of anterior-posterior shear displacement. Examination of the constructs demonstrated similarities between components tested via this new method and components retrieved from patients. Comparisons indicate that the shear fatigue test may stress the components as much or perhaps more than what was seen clinically.

A mathematical simulation of the evolution of nitrogen concentration profiles in iron samples is presented. The nitrogen concentration profiles are produced by a nitrogen microwave post-discharge. This mathematical model takes into account the nitrogen concentration evolution from the very beginning of the process and describes the formation and growth of compact nitride layers. This model also proposes a description of how the solubility limits in each growing phase are attained during the layer formation. An approximate analytical solution of Goodman’s type for the model is sought. This leads to a system of differential algebraic equations (DAE). Then, the DAE is finally numerically solved. The steady state of the process is also studied within the model. In this case, analytical representations of the nitrogen concentration profiles and the diffusion coefficients are found

Magneto-rheological (MR) fluids, as smart fluids, are suspensions of micron-sized magnetic particles, such as iron particles or cobalt, in a silicone or hydraulic oil carrier fluid, which can change from the liquid state to a semi-solid state in several milliseconds in the external magnetic field. In this paper, the produced chain, which will give rise to the MR effect, is investigated by the magnetic force between two particles, the relationship between the produced shear torque, and magnetic particles are proposed. A set of testing systems, including the plate-on-plate MR fluid shearing test rig, is built to study the percentage of magnetic particles in MR fluid. The magnetic field in the gap, before and after the gap is added with MR fluid, is investigated by measuring and calculating. The results validate the effect of the content of magnetic particles in MR fluid on the shear performance.

For a number of years, luminescent bacteria have been used as an indicator species for acute toxicity of substances in aquatic marine environments. Various other higher organisms have been used for this exact same purpose. Many of the higher organism test evaluations have been used successfully, but they have a few limitations, such as a low number of organisms exposed to toxicant during a test, less than desirable precision and the need for highly trained individuals to run the tests. One luminescent bacterial bioassay includes many organisms, can be run rapidly and requires training in sample dilution techniques. ASTM Subcommittee D02.12 has been working to develop an ecotoxicity method to evaluate the effects of lubricant formulations on luminescent bacteria. The theory describing this method, as well as the D02.12 method development activities, will be discussed.

In this paper, a method of intensive quenching in water salt solutions, known as the IQ-2 process, is considered. To realize the IQ-2 process, water salt solutions were used, including with NaNO3, Na2CO3, NaCl, CaCl2, MgCl2, Ca(OH)2, and others salts. It is shown that the effectiveness of intensive quenching can be improved via the use of water salt solutions of optimal concentration. In order to prevent the corrosion of steel parts, a small amount of Ca(OH)2 was added to water salt solutions of sodium and calcium chloride to create a pH of 8 to 12. The proposed technology is less expensive compared to conventional quenching methods while providing the same or better end results in terms of increasing the service life of steel parts and tools and components made of powder metal materials. It is shown that the intensive quenching of tools by water salt solutions of optimal concentration increases the service life of tools by 1.5 to 2 times as compared with the oil quenching process.

Dept. of Mechanical and Materials Engineering Portland State Univ., P.O. Box 751, Portland, OR, 97207-0751

Tensile loading of bonded point supports is considered as the critical load case for adhesive material, e.g., silicone applied to such kinds of fixtures. From a durability point of view, the following defects of two-component adhesives are expected to have a significant impact on the response to this loading regime: the wrong mixing ratios of the adhesive components, inhomogeneous mixing due to insufficient or poor mechanical mixing procedures, load degradation of the adhesive bonding material, local degradations of the bonding, e.g., bubbles or poor adhesion. In order to investigate these aspects, different experimental approaches have been pursued. Regarding the mixing ratio aspect, material tests were performed with systematically varied mixing ratios for the analysis of the elastic and strength properties while for the other topics, tensile tests of bonded point supports were evaluated in detail. Cyclic tests of point supports in the tensile load regime were set up, differing in amplitudes and maximum peaks of the cycles, in order to analyze the impact of load histories on the mechanical characteristics of the specimens. For point supports subjected to monotonically increasing loads the qualitative assessment of the fracture surfaces revealed the existence and the potential impact of disturbances inside the bonding, such as bubbles or locally lacking adhesion, on the damage behavior and on related inferior mechanical performance. The main motivation for this kind of research is to improve confidence in the durability of bonded designs. Thus, our activities were focused on aspects which might affect durability from an application point of view, not from a purely academic one. Especially in Germany, the confidence of the authorities in this joining technique has to be strengthened by demonstrating a high degree of robustness in the application, and in view of the risk associated with potential in-field problems.

There has been increasing interest in the use of recycled polymer composites as a replacement for timber piling in coastal and waterfront environments. This trend is expected to grow because polymeric piling is more attractive than timber when life cycle costs are factored in, and also because polymeric piling is a creative method for the recycling and reuse of tons of plastic waste. However, composites face obstacles because they do not have a long track record of use in civil engineering structures. Polymeric piling is typically made of high density polyethylene (HDPE) and reinforced with fiber reinforced polymer E-glass (FRP) or steel. This paper summarizes the current state of the art in polymeric piling practice, including (1) the mechanical properties of piling made of recycled polymers; (2) the durability of recycled polymers in aggressive soils; (3) the compressive creep of recycled HDPE and FRP; (4) drivability; (5) design considerations such as skin friction, end bearing, and buckling; and (6) load testing of polymeric piles.

In this paper, a detailed discussion is provided regarding an effect of the accuracy of temperature measurements on the evaluation of heat transfer coefficients (HTCs) during quenching in liquid media. Some published results on the use of test probes for HTC determination are discussed. These results show that the values of HTCs obtained under the same quench conditions and using test probes of the same size differ by 5 to 8 times. This is a major reason for the writing of this paper. Understanding why there is such big difference in the experimental values for the HTC is very important in planning a study for the development of a global database for different kinds of quenchants. This understanding will help scientists and engineers to develop new, correct data on HTCs needed for computer simulations and for improving the quenching processes of steel parts.

The review on boiling heat transfer addresses many critically important problems including the disregard of the pumping effect of growing bubbles (PEGB), the so-called “model of the theatre of director” (MTD), and the universal MTD-based correlation. In this review, with respect to PEGB, MTD, and the MTD-based correlation, emphasis is placed on the critical consideration of the traditional model of the theatre of actors (MTA). The universality of the MTD-based correlation once again is demonstrated, including forced-boiling heat transfer in microsystems. The MTD, in combination with so-called multi-factoring concept, represents a unified framework for the investigation of the diversity of boiling heat transfer curves, including boiling hysteresis and the specific boiling regimes characteristic for microsystems.

The potential use of vegetable oil derived industrial oils continues to be of great interest because vegetable oils are relatively non-toxic, bio-degradable, and a sustainably produced basestock alternative to petroleum oil, a non-renewable basestock. For the conservation of the environment, bio-mass materials, such as vegetable oils, are desirable as substitutes for petroleum oil in heat treatment. Therefore, it is expected that these basestock materials will continue to be of increasing interest in the heat treatment industry. However, the fatty ester components containing conjugated double bonds of the triglyceride structure of vegetable oils typically produce considerably poorer thermal oxidative stability than that achievable with petroleum base-stocks under typical use conditions. This is especially true when a vegetable oil is held in an open tank with agitation and exposure to air at elevated temperatures for extended periods of time (months or years). Furthermore, when used as quenchants, furnace loads of hot steel (850 °C) are typically rapidly immersed and cooled to approximately 50 °C to 60 °C bath temperatures for steel hardening applications. Clearly, for this application, reasonable thermal-oxidative stability is essential. This paper reviews the work completed thus far in screening various vegetable oils as potential steel quenchants both with and without antioxidants. Particular focus is placed, where possible, on comparing pressure differential scanning calorimetry as a potential screening method with the more commonly used (for this application) modified Indiana Stirring Oxidation Test. In addition, the general impact of oxidation on the quenching performance of the better vegetable oil candidates is shown.

In the present study, fluorine in recycled gypsum was focused on with regard to the morphology in gypsum as well as the leaching behavior when gypsum is mixed with soil as a recycling measure of soil improvement. The analytical results using an electron probe micro analyzer indicated that the chemical form of fluorine in recycled gypsum is calcium fluoride and fluoride apatite, and the form does not change after a leaching test on the soils according to the Japanese Leaching Test No.46 (JLT-46). JLT-46 was adopted for not only recycled gypsum but for mixtures of recycled gypsum and decomposed granite soil, exceeding the environmental standard limit value of 0.8 mg/L for both, by 6.8 and 2.4 mg/L, respectively. This means that countermeasures are prerequisite in the utilization of recycled gypsum as a soil improvement material. A pH-dependence test indicated that leaching of fluorine increases along with the decrease of pH in acidic conditions. A parallel batch leaching test using water indicated that release of fluorine occurs relatively slowly compared with calcium sulfate which reaches chemical equilibrium in less than 0.5 h. Decomposed granite soil has the effect of holding fluorine from leaching.

An improved wall heat flux partitioning model at the heated surface was developed by Yeoh This model, coupled with a three-dimensional two-fluid model and Multiple Size Group model, has led to satisfactory agreement being achieved between the model predictions and experimental measurements. Nevertheless, one shortcoming is the reliance on empirical correlations for the active nucleation site density in the wall heat flux partitioning model. This discrepancy brings about uncertainties, especially in appropriately evaluating the vapor generation rate, which greatly influences the model prediction on the axial and radial void fraction profiles within the bulk fluid flow. By considering the fractal model with the aforementioned subcooled boiling flow model in the absence of empirical correlations for the active nucleation site density, a comprehensive mechanistic model to predict vertically oriented subcooled boiling flows is developed. The proposed model is assessed against the experimental data of axial measurements of Zeitoun and Shoukri and the radial measurements of Yun and Lee for vertical subcooled boiling flows within annular channels. Improved model predictions are obtained when the model is compared against typically applied empirical correlations for active nucleation site density. Discussions on the agreement of other two-phase flow parameters are also presented.

The performance of Zr1NbSnFe alloys within the range of Sn 0–0.65 % and Fe 0.03–0.35 % were studied through irradiation of fuel rods in two pressurized water reactors (PWRs) operating with significantly different fuel management strategies. Material test rod irradiations have also been launched in order to determine irradiation growth and corrosion behaviour on tubes irradiated under conditions representative of guide tubes. Results show that the increase in tin content up to 0.3 % does not significantly change the corrosion resistance nor the hydrogen pick-up compared to Zr1Nb alloy, while ensuring a higher creep resistance and an improved dimensional stability. On the contrary, at 0.5 % Sn, the corrosion resistance can be significantly degraded under demanding conditions. The iron addition to the alloy can be considered as a second order parameter for both corrosion and creep properties.

As a result of the long history of use of polyethylene systems in natural gas distribution systems, the advantages of thermoplastic distribution systems over steel systems are clearly recognized. These advantages include both short-term economic benefits due to advantages in total installed costs and long-term life service benefits due to the excellent corrosion resistance of thermoplastic systems. Historically, a weak point of the thermoplastic systems currently in use commercially are limitations in use due to operating pressure and end use temperature constraints. Initiatives exist within the natural gas distribution sector to identify materials capable of offering the advantages of currently available thermoplastic systems while extending the operating pressure range and end use temperature. Polyamide 12 has been identified as one material capable of meeting these needs. In 2004, a project was initiated by UBE Industries, Ltd. to evaluate the feasibility for use of polyamide 12 in natural gas distribution systems in the United States. The objective of the project was to develop a polyamide 12 natural gas distribution system capable of operating at pressures greater than that imposed by current restrictions and at temperatures above those achieved by commercially available thermoplastic systems. U.S. regulatory restrictions limit the use of thermoplastic systems to a maximum operating pressure of 125 psig. As the project progressed, the scope was expanded to include global activities. The project was broken into two distinct phases. Phase 1, from February 2004 to December 2006, included a comprehensive laboratory evaluation and limited field service use to determine the feasibility for use of polyamide 12 natural gas distribution systems operating at pressures greater than 125 psig and elevated temperatures. Long-term strength performance, slow crack growth and rapid crack propagation characteristics, the effect of secondary stresses along with extensive testing to accepted industry test methods were evaluated. Studies were conducted to develop a full set of installation, maintenance, and operating procedures for the use of polyamide 12 systems. Additionally, several small scale private property installations took place as part of the phase 1 project. Based on the positive results from laboratory and field evaluations of polyamide 12 systems, a phase 2 project was developed. The objective of the phase 2 project was to commercialize the use of polyamide 12 systems for use at pressures greater than 125 psig. During this phase of the project, installations are being performed with utilities in North America within their respective operating areas. These installations are being performed under special permits in cooperation with the respective federal and state regulatory bodies. As a separate activity, samples have been removed from the trial installations at specific time intervals and characterized for retention of physical and mechanical properties. The sample removal and evaluation study is an ongoing activity. The results of the project demonstrate that polyamide 12 offers a viable, cost effective alternative to steel pipe for systems operating above the range of currently available thermoplastic systems capability. In terms of both pressure bearing capabilities and high temperature operating performance, polyamide 12 systems extend the range of use for thermoplastic systems in natural gas distribution applications. The paper presents an overview of the laboratory analysis and field installation activities performed in the polyamide 12 gas distribution systems project. The data are presented in the context of compliance to the active ASTM polyamide 12 standards.

Although the complete mechanisms are not yet fully understood, it is well established that the secondary phase particle (SPP) size distribution and chemical composition have a crucial affects in the reactor corrosion rate and hydrogen uptake in boiling water reactor (BWR) cladding. To further study these effects, different selected fuel rod assemblies with standard LK3 cladding materials that have been irradiated in KernKraftwerk Leibstadt (KKL) for three, five, six, seven, and nine annual cycles were investigated using transmission electron microscopy (TEM). TEM analysis of the samples showed that the average size of SPPs increases as the small SPPs are dissolved during irradiation. After three cycles the Fe–Cr bearing SPPs have been identified as completely amorphous over the whole range of examined samples and the Fe–Ni bearing SPPs remained crystalline. The EDX analyses of several Fe–Ni bearing precipitates show that the Fe/Ni ratio stays more or less constant for the irradiated material at 1.5 to 1.6 and drops to about 1 after fast fluence of 17.9×1021 n/cm2 (>1 MeV) for nine cycles sample. Results from this study confirms that the increased oxide thickness, the higher hydrogen content, and the accelerated growth of the rods at rod average burnup of 78 MWd/kgU goes along with a change in the appearance of SPPs by TEM.

It is essential to maintain cleanliness in an oxygen system as many accidents occurring in oxygen-enriched environment indicate contamination as a major source of ignition. Computational fluid dynamics (CFD) analyses show that valve seats, T-joints, elbows and spots with complex geometries are possible locations for accumulation of the dust particles. It is important to understand the mechanisms of contaminant accumulation, the initiation of fire and its propagation in valves and regulators in order to suggest ways for their prevention. As contaminant dust particles flow with oxygen through valves and piping systems, the solid dust particles impact or rub with the pipe wall or with each other. This results in the building up of static electric charges in them. These charged dust particles may eventually accumulate and lead to electrostatic discharge, thus creating a potential cause of initiation of fire. The aim of the present work is to develop a mathematical model based on CFD, of the dispersion and settling of micron-sized charged dust particles in the pressure regulator, commonly used in oxygen application. A two-dimensional numerical model of flow, dust particle dispersion and particle settling, utilizing finite volume approach, has been developed on FLUENT 6.3.26 platform. The results show that there is a possibility of electrical discharge due to the settlement of charged dust particles if a regulator is attempted to be reopened within a short time of it being closed. Since it is practically impossible to make all oxygen systems free of contaminants at all times, it may be worthwhile to analyze ways about how to avoid ignition even in presence of large concentration of dust particles. The present study may give an insight into the possibility of ignition and offer suggestions to avoid it through appropriate system configuration and operation timings.

The European Mines Safety Commission was established in 1961 in response to a mining disaster in August 1956 at Bois du Cazier, Belgium. Hydraulic hoses were ruptured and the pressurized flammable hydraulic fluid was ignited, resulting in 267 deaths. A commission of technical experts from Europe was formed to recommend replacements for flammable oils in critical applications. Specifications were developed for fluids used in underground pumping systems and mining roof support equipment. The initial report was last updated in 1994 and is now known as the 7th Luxembourg Report. This document has been particularly important for the underground mining industry. The Report is in the process of being updated by conversion of the test methods and requirements to ISO standards. The 7th Luxembourg Report contains four categories of required testing: Fire resistance, technological properties, ecological properties, and toxicological properties. Approval testing must be conducted by a certified independent laboratory. This paper will discuss each of these categories and give examples of the tests required. Particular emphasis will be given to high water content mining hydraulic fluids and the problems encountered with corrosion resistance and emulsion stability. A new classification for water glycol fluids with lower water content has been added in recent years. An example will be shown of a fluid in this classification that meets all of the 7th Luxembourg requirements and provides excellent pump lubrication with no derating of the pump.

In order to get a better understanding of the mechanism governing hydrogen absorption behavior in Zr-based alloys, various characterization techniques were applied to the oxide layers of three alloys: Zry-2, GNF-Ziron (Zry-2-based alloy with ∼0.26 wt % Fe), and VB (Zr-based alloy containing ∼0.5 wt % Sn, ∼0.5 wt % Fe, and ∼1 wt % Cr). Out-of-pile corrosion tests were carried out in 400 °C steam and 290 °C LiOH water. For both tests, the hydrogen absorption decreased with higher iron content in the alloys, in the order of Zry-2>GNF-Ziron>VB, despite different kinetics of a parabolic law in the former test and a linear law in the latter test. The acceleration of hydrogen absorption in the LiOH water was ascribed to the formation of degraded or open grain boundaries up to locations very near the metal/oxide interface. The pre-transition steam oxides of 1.4–1.7 μm had a double layer structure composed of the outside non-protective oxide of monoclinic ZrO2 with faster diffusivity and the inside barrier layer of predominantly tetragonal ZrO2 with slower diffusivity. The thickness of the barrier layer of about 0.8–0.9 μm was not changed for the different alloys. The diffusion coefficient of deuterium in the VB oxide was approximately half of that in the GNF-Ziron oxide. This factor for the diffusivity was consistent with their hydrogen pickup performance. The higher compressive stress in the barrier layer was directly linked to the higher hydrogen pickup resistance of the alloys. Preferential dissolution of alloy elements from the second-phase particles (SPPs) into the oxide matrix was evinced for iron, and was very limited for chromium and nickel. These two elements had a tendency to exist as precipitates in the oxide layers, chromium mainly as oxide, and nickel mainly as metal. The superior hydrogen absorption performance of VB containing higher iron content and the SPPs with larger size and number density was attributable to the dissolved iron effect and higher compressive stress state generated from the delayed oxidation of the SPPs in the barrier layer.

This paper presents the results of a study of the physical and environmental properties of pre- and post-processed fly ashes (termed Raw and Processed fly ashes, respectively). The ashes were collected from a coal-fired power plant in the northeastern U.S. which utilizes a carbon burn-out unit (CBO) to prepare the fly ash for concrete and other construction applications. Measured physical properties included carbon contents via loss-on-ignition (LOI), specific gravities, gradation analyses, and scanning electron microscopy (SEM). In addition, total and leachable concentrations of lead, selenium, and arsenic were determined. Leachable concentrations were determined for leaching solution pHs varying between 1.5 and 11.5. When compared to Processed fly ash, Raw fly ashes had an expectedly higher LOI (approximately 2% versus 6% carbon content, respectively) and lower specific gravity (2.37 versus 2.18, respectively). Although the total metal content of the fly ashes was similar, leachable metal concentrations were notably higher for the Processed fly ash over the full range of leaching solution pHs evaluated. The test results indicate that the CBO process, at times necessary to create usable fly ash, can result in fly ashes with notably altered physiochemical properties that lead to higher leachable contaminant concentrations.

Studies carried out with glass electrode in anhydrous ethanol and ethanol-water solutions for measuring pH values have shown that this parameter depends on the solution composition, the contact time with the solution, the utilized temperature, and the type of electrolyte used. It was also observed that the glass electrode behavior in an acid medium differs from an alkaline medium. These studies provided correction factors for pH values from 2 to 12, allowing the realization of proper measurements of the hydrogen ionic activity in the ethanol-water and anhydrous ethanol solutions. However, these correction factors could not be applied to the fuel ethanol. Alternatively, a new method was developed for the correction of the pH values, which can be applied in hydrous and anhydrous fuel ethanol samples.

Equipment that operates under high-temperatures can be protected with NiAl intermetallic coatings because of their metallurgical stability. This study evaluates the effect of chromium carbides added to Ni–Al intermetallic coatings processed by plasma transferred arc (PTA). Mixtures of Ni and Al powders with and without different Cr23C6 fractions (15, 30, and 45 wt %) were deposited by PTA on an AISI 304 stainless steel plate, using two different currents (100 and 150 A). Coatings were evaluated for the presence of welding defects, and the developed microstructures were characterized by X-ray diffraction and scanning electron microscopy. Vickers microhardness and semiquantitative energy dispersive spectroscopy chemical composition were also determined. NiAl and Cr7C3 development was confirmed by X-ray diffraction analysis. A combination of NiAl/Cr–Fe–Ni phases was identified. The hardness was strongly related to the formed phases and volume fractions. The present study shows that PTA hardfacing can be used to produce reinforced intermetallic coatings for high-temperature applications, showing significant advances toward the development of coatings that can withstand severe operation conditions.

From 1966 to 2009, the corrugated polyethylene pipe industry has grown from its first introduction to greater than a $2.5 × 109 industry in North America and from 4 in. (100 mm) only to a product diameter range of 2 in. (50 mm) through 60 in. (1500 mm). Markets have changed and grown as well, from predominantly agricultural drainage applications to housing, commercial development, transportation, mining, industry, forestry, storm sewer, sanitary sewer, turf drainage, and stormwater treatment. Increases in diameters and expansion of markets have led to corresponding changes in manufacturing processes and development of appropriate standards and specifications.

In order to understand the correlations between the laser shock processing and materials’ response, an as annealed plain carbon steel 45 (equivalent to AISI 1045) was investigated by means of a Nd:glass laser setup with 1054 nm wavelength and 20 ns short pulse. The microstructure evolution was analyzed with optical microscope, scanning electron microscope, etc. The experimental results indicate that the strengthening effects can be obtained under the used confinement conditions and the ultra-high strain rate of laser shock. After laser shocking, the cementite in pearlite crashes the subject to their orientations, and the pro-eutectoid ferrite produces a great number of dislocation etched pits and lens-like twins. The hardness of pearlite and pro-eutectoid ferrite increases by 70 and 55 Hv, respectively, and the residual compressive stress of the steel reaches 425 MPa on the shocked spot.

The hydrogen concentration in zirconium alloys used in nuclear fuel cladding can be determined quantitatively, rapidly and non-destructively with a spatial resolution of 25 μm by neutron radiography. Because the total neutron cross section of hydrogen is more than one order of magnitude higher than that of zirconium, low concentrations of hydrogen can be measured. Calibration measurements have been performed and confirm the linear dependence of the total macroscopic neutron cross section on the hydrogen to zirconium atomic ratio as expected from theoretical analysis. The fast and non-destructive character of the method provides the possibility of in situ investigations. Examples of in situ investigations of the diffusion of hydrogen into Zircaloy-4 and of hydrogen uptake during steam oxidation are given. For the steam oxidation experiments a fast hydrogen uptake was found during the first 10 s. After this first step, the hydrogen concentration in the sample decreases slightly. If breakaway oxidation occurs, additional hydrogen absorption takes place. The hydrogen concentration can then increase by nearly one order of magnitude by this process. The influence of variations in the total gas flow and the steam flow on the hydrogen uptake was investigated, too.

Steam heating systems become obsolete because of water hammering, noise, high heat loss, installation cost, and poor control. The replacement of metal piping by a coaxial two tube thermoplastic conduit resolves all issues of current steam heating systems along with improvements in heating comfort level, energy efficiency, and maintenance and equipment durability. Polysulfone materials are proposed for the plastic conduit and fluoropolymers for the end connections to the radiators.

A highly stable ternary complex of iron(III) with 5-(4-nitrophenylazo) salicylic acid (NPAS) and Eosin (Es) in acidic medium at room temperature gave a maximum absorption at 545 nm with a molar absorptivity 2.81×104 L mol−1 cm−1. A spectrophotometric method using these ligands was developed and optimized in terms of pH, stability of the complex, amount of reagent required, sensitivity, linearity, and the effect of various foreign ions was studied. The linear range for iron(III) determination is 0.18–6.0 mg L−1. The method was sensitive, accurate, and all the reagents were stable under the working conditions. Moreover, the method was easy to perform for the determination of iron in pharmaceutical and water samples.

A new solvent for the crop protection formulations is described. Solvents are essential components in various pesticide formulations. Many traditional solvents used in agricultural applications are currently under scrutiny because of increasing environmental and regulatory concerns. Agrochemical formulators are facing a need to find alternative solvents that are environmentally friendly while continuing to deliver traditional solvent performance. A new polar solvent, an archetype of a novel class of products containing a tertiary amide group combined with an ester function namely Methyl 5-(dimethylamino) 2-methyl 5-oxopentanoate (RHODIASOLV Polarclean) (RHODIASOLV is the registered trade mark of Rhodia, Cranbury, NJ) is described. This new solvent exhibits an outstanding safety and non toxic environmental profile. Additionally, many agrochemical active ingredients have good solubilities in this new solvent. Hansen solubility parameters demonstrate the high level of solvency properties of this ester-amide when compared to the commonly used agrochemical solvents. In addition to meeting the customer requirements on delivering good solvent performance, the raw material utilized in the manufacture of this solvent is a by-product of polyamide manufacture and has been selected to meet the sustainability criteria.

An investigation into the field tests used to test for ammonia in fly ash was conducted for comparison to the ASTM C311-07 ammonia determination by the ion selective electrode (ISE) test method. “Ammonia tube result” (ATR) refers to a Gastec tube reading on trapped gas over a slurried fly ash mixture that is correlated to the ISE results by linear regression. This paper contains the following: A comparison of the actual ammonia measurement in the lab by ISE and EPA Method 350.1. Testing was performed on the same samples and in duplicate as a confirmation. The statistical correlation of ASTM C-618–08a, class C fly ash by the ATR to the ASTM C311-07 test method is demonstrated which is comparable to the correlation with the EPA method. A discussion of the differences between the ATR and referenced analytical methods on both ASTM C 618 - 08a class C and class F fly ashes is presented. The effect of sodium hydroxide addition as a catalyst for the ammonia release was significant for both ASTM C-618–08a class C and class F fly ash but differences were noted and are presented.

ASTM D 3350, Standard Specification for Polyethylene Plastics Pipe and Fittings Materials, was originally approved and published in 1974 and has increasingly been referenced in numerous F17 Piping Application Standards. This paper/presentation will review the background of the original standard, provide how it has transformed as the industry has evolved to improved materials and “salt and pepper” blending for pipe production, and identify the challenges in modifying the standard to apply for all polyethylene piping applications. ASTM D 3350 is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.15 on Thermoplastic Materials.

The increase in the world’s population has led to an increased demand for agricultural products, which in turn calls for more intensive farming and higher crop yields. To minimize the impact on the environment, society demands more environmentally-friendly products to be used. Regulatory authorities have answered the public’s call for “greener” chemistries by applying pressure to not only replace the more harmful active ingredients, but also the formulation inerts. The Crop Protection Industry has used nonylphenol ethoxylates (NPEs) as inert ingredients in pesticides and spray adjuvants for decades. The implementation of European Directive 2003-53 EC, which bans the use of NPEs, has caused many American markets to look for alternatives for nonylphenol-based surfactants as well. Substitute chemistries typically are chosen based on hydrophile-lipophile balance (HLB) values and cloud points. This study uses an alternative method of selection by evaluating the emulsifier performance in commonly used solvents in emulsifiable concentrates (ECs), emulsion oil-in-water (EW), and oil dispersion (OD) formulations. A modified cylinder test is used for the evaluation of a wide range of surfactants. The emulsifier, solvent, and hard water are placed in a glass cylinder, inverted multiple times, and allowed to stand undisturbed for 24 h. The emulsification performance is then calculated based on the phase height of each emulsion, which is then compared to the performance of the systems, which includes NPEs. The solvents used in the study are not only the common naptha-based solvents as seen in many ECs, but also in the more environmentally-friendly formulation types such as EWs and ODs, which use mineral oils, seed oils, and seed oil methyl esters. This method offers an easy way to reformulate NPE-containing formulations with regard to sustainability and an emulsifier selection guide for environmentally-friendly formulations in general.

Sample preparation methods for four-wipe composite dust wipe samples, used by nine different laboratories accredited under the U.S. Environmental Protection Agency (EPA) National Lead Laboratory Accreditation Program (NLLAP), were evaluated to select two methods most likely to provide the best overall performance among multiple laboratories, based on accuracy, precision and practicality of the methods. The best performing methods involved (1) hot nitric acid/hydrogen peroxide digestion and (2) nitric acid ultrasonication. In a second round of testing, two sets of composite dust wipe samples with known amounts of lead were submitted blind to each of the nine laboratories to be prepared for analysis using these two sample preparation methods. Results showed that both methods are capable of meeting all EPA NLLAP requirements for accuracy (recovery) and precision. The ultrasonication method had superior performance at lower cost.

In addition to the sulfur determined as a part of the crude assay, it is important to know the concentration levels of a number trace elements in crude oils. A method is described for the multielement metal analysis of crude oils using inductively coupled plasma atomic emission spectrometry (ICP-AES). The samples are diluted with an organic solvent before measurements. Metallo-organic compounds dissolved in organic solvents are used as calibration standards. Precision of analysis was established based on an ASTM interlaboratory study. NIST Standard Reference Materials of crude oils where available were analyzed to estimate the bias of the new test method.

Beyond their application as sealants, silicone formulations are used as adhesives in insulated glass and structural glazing applications. The adhesion durability of such assemblies is a function of both the adhesion at the glass-interface surfaces and the internal cohesion of the adhesive. Failure in the bulk of the adhesive will occur if external stresses exceed the ultimate strength of the adhesive or when the movement capability of the adhesive is lower than required by the application. The most often observed reasons for failure are, however, substrate-adhesive interface ruptures. If similar silicone adhesives are used in different building projects, the substrates can vary widely, leading to many different interfaces. Interface adhesion can be improved by modifying the substrate surface, modifying the adhesive formulation, or using a primer. In this work, improved adhesion durability on different substrates will be shown with an improved version of a two-part silicone adhesive used for insulated glass and structural glazing applications, which was introduced in Europe in 2010. Results without primer and with the use of either a wet primer or a dry SiOx (Pyrosil®) flame treatment will be shown. Adhesion durability after water immersion, UV irradiation, and high humidity will be reported for new low E insulated glass coatings, powder coated aluminum, stainless steel, and some other standard building substrates.

The present work deals with two essential degradation mechanisms of zirconium alloys: Hydrogen behavior and microstructural transformations due to neutron irradiation. The studies were carried out by using samples taken from Zircaloy-4 components, which remained for 14 years in the Atucha I pressurized heavy water reactor, accumulating neutron fluences of up to 10 22 neutrons / cm 2 . A hydrogen/deuterium solubility increase was observed in both dissolution and precipitation processes. With the aim to follow this evolution with radiation damage recovery, the irradiated samples were annealed for different periods at 350 and 400 ° C in a differential scanning calorimeter (DSC). These temperatures were chosen to reproduce those reached by spent fuels in the early stages of the dry storage (DS). Between intervals, the terminal solid solubility temperatures in dissolution (TTSSd) and in precipitation (TTSSp) were determined. They were also determined after additional annealing at 500 and 600 ° C , trying to simulate long periods at DS. The hydride morphology and the metallurgical state of the Zr ( Fe , Cr ) 2 second-phase particles (SPPs) were followed between annealing by optical microscopy, analytical electron microscopy, synchrotron light X-ray diffraction (SXRD), and DSC. As a brief summary, we found from the first to the last run of the annealing sequence an increase of 55 ° C in TTSSd and 40 ° C in TTSSp on average. The optical and transmission electron microscopies (TEM) indicate that in the material in the irradiated condition, exists a hydride size distribution of four orders of magnitude, from 10 nm to 100 μ m , but biased to sizes smaller than 5 μ m . A complete amorphisation of the SPPs was observed in high fluence samples by TEM and SXRD. Similar TEM observations made in irradiated samples annealed above 400 ° C show a re-precipitation process of nano-SPPs forming clusters. The re-precipitation is affected by kinetics: The SPPs crystallization temperature, T c , rises from 450 to 500 ° C as the heating rate increases from 5 to 20 ° C / min . The measured heat of crystallization was 27.3 ± 2.1 kJ / mol ( Fe + Cr ) .

The size, shape, and texture of aggregate particles are important because these physical characteristics influence the engineering properties. Recycled organic aggregates have advantageous physical and mechanical properties for geoengineering applications, but the particle shapes and textures have not been well quantified and evaluated. Three pairs of recycled organic aggregates were studied in this investigation: nylon and polyethylene terephthalate (thermoplastics), ground and crumb rubber (elastomers), and pine and oak wood (natural organic materials). The particle flatness, elongation, and sphericity were calculated for representative samples of each aggregate. The particle index of the shape and texture was measured per ASTM D 3398, and this test method was determined to provide a meaningful assessment of irregular geometrical characteristics. With the exception of nylon chips, recycled organic aggregates contain a high percentage of flat and elongated particles with Lmax:Lmin ratios that are much greater than those observed in crushed stone, gravel, and sand. Void volumes are much higher, resulting in particle indices between 30 and 50, as compared to indices of less than 20 for natural, inorganic aggregate.