bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Relation of Tallowamine Ethoxylates to Dynamic Surface Tension and Field Performance
Authors: Friloux KM , Berger PD 
Published: March 2009

The uptake of active ingredient from sprayed formulations via foliar penetration has been demonstrated to be increased by the use of surfactants. The surfactant may increase the spray solution's ability to wet the leaf surface, or facilitate translocation of the active ingredient through the stomata into the leaf.
It has been shown that the structure of surfactants can influence the ability of the surfactant to promote these mechanisms of transport of the active ingredient. The amount of Ethylene oxide in the hydrophilic portion of the surfactant is one such factor that has been linked to the translocation of the active ingredient.
Various hydrophobes such as fatty alcohol and nonylphenol, ethoxylated to various degrees, have been used to show the effect. Another such hydrophobe, tallowamine, is ethoxylated and used as a surfactant in water soluble herbicides. In this study, a series of tallowamine ethoxylates of varying degrees of ethoxylation from 2 moles of Ethylene oxide to 20 moles of Ethylene oxide were evaluated to determine the effect of the amount of Ethylene oxide on surface properties.
Aqueous solutions of the surfactants were measured at different frequencies for dynamic surface tension using the maximum bubble pressure technique. The reduction of the liquid's surface tension increase wetting and spreading of the liquid onto the foliar surfaces thus facilitating translocation of the active ingredient. By measuring the modification of the surface tension of the liquid versus the Ethylene oxide content of the surfactant, we will support the data previously compiled.
Also included in the study will be measurements of the dynamic contact angle of the aqueous solutions on the surface of a leaf, as well as other surfactant properties.
Dearomatized Tailor-made Hydrocarbon Fluids in Co-Adjuvants or Adjuvants in Tank Mixes
Authors: Frisch PD , Verbelen RA 
Published: March 2009

Specific dearomatized hydrocarbon fractions with boiling ranges between 220 and 310°C can significantly increase the performance of active ingredients in certain herbicides, fungicides and insecticides when they are incorporated, in combination with surfactants, in the formulations (co-adjuvants) or used as adjuvants in tank mixes.
With the help of these tailor-made fluids, the biological activity of the active ingredients can be improved or modified. Efficacy is significantly increased and other important physico-chemical characteristics; such as, application properties, volatility versus penetration and mode of action, can be modified. The adjustment of these parameters adds formulation flexibility, increases activity which results in cost savings (less pesticide is required per hectare) and environmental benefits (reduction of undesirable residues).
To demonstrate these benefits, two specific pesticides were selected: an insecticide (new generation of pyrethroid) and an herbicide (diphenyl ether family). These active ingredients were then formulated using these tailor-made dearomatized hydrocarbon fluids, other coformulants and specific surfactants and their performance assessed in green house and field trials. Comparisons with other established adjuvants are included where available.
Building Sealants in Russia
Authors: Berman OY 
Published: March 2009

In this paper, the author presents information concerning building sealants in Russia.
The paper includes data of demand and provision of construction industry with sealants, the features of sealants application and comprehensive description of types and application areas of sealant materials.
Technical requirements and physical properties, current experimental data on performance capabilities of some types of sealants in Russia are presented and discussed.
Possibilities of organization of a joint sealants business in Russia are described in the conclusion.
History of Building Joint Sealants
Authors: Scheffler MJ , Connolly JD 
Published: March 2009

The use of sealants in facades became more widespread in the 1950s and 1960s with the increasing use of curtain wall construction. While most sealants specified for new construction today are silicone or urethane-based, older buildings may contain polysulfide and acrylic-based sealants.
For investigators trying to identify sealants used on older buildings, it is often useful to know which sealants were in common use when the building was constructed, or when the building was repaired. This paper briefly discusses and reviews the history of the use of commonly used building sealants over the last fifty years, detailing when specific sealant types were first developed, when they came into widespread use, or fell out of favor.
Historically, sealant selection has depended upon many factors such as the type of substrate, movement requirements, prior sealants used, cost and aesthetics. Improvements in performance capabilities of sealants and innovations such as structural glazing are discussed.
Some sealants have been found to contain hazardous substances. For example, some polysulfide sealants applied during the 1960s contain polychlorinated biphenyls (PCBs). Issues related to hazardous materials in sealants will be discussed as well as the performance consequences of the current change to sealant products to make them less harmful to the environment.
A Review of Recent Developments and Improvements in Accelerated Outdoor and Indoor Xenon Weathering Devices and Methodologies
Authors: Puttnan WJ , Pekara D , McGreer M 
Published: March 2009

Accelerated outdoor weathering has a history which extends back at least 50 years. The advantage of this type of testing is that the sun's natural solar energy spectrum is used to irradiate the specimens under test. Since this is an outdoor method, variations in test conditions occur due to the natural seasonal weather differences. Recent improvements in fresnel concentrator accelerated weathering devices such as day and nighttime temperature control, and new moisture cycles are described that minimize seasonal effects.
Since the development of artificial tests in the early 1900's, many types of artificial light sources have been introduced. Improvements in xenon accelerated weathering chambers have enabled development of new test methods utilizing filters that provide a very close approximation of sunlight especially when compared to fluorescent and carbon arc light sources. This paper will also include a description of an advanced air-cooled xenon arc test apparatus for the accelerated exposure of materials.
Fatigue Prediction Based on Computational Fracture Mechanics
Authors: Chang AT , Nelson NW , Cordes JA , Kim Y-J 
Published: March 2009

A general numerical method has been developed to predict fatigue crack initiation and fatigue crack propagation under cyclic loads. Finite element technique is employed to model specimen geometry. The method requires uniaxial stress/strain material data only; empirical fatigue constants are not required. It determines the number of load cycles for crack initiation or for crack propagation based on fracture energy, W, and dissipated energy per cycle, E. Fracture energy is the plastic-strain energy contained in a Dugdale-type cohesive stress zone located near an initial defect. The size of the cohesive zone of a specimen is established by a computational procedure that simulates elastic-plastic fracture under static loading. Dissipated energy per cycle is the plastic-strain energy in a hysteresis loop that exhibits cyclically stable behavior after “shake-down.” The number of cycles to initiate a crack or to propagate a crack to a finite amount is obtained by dividing the fracture energy, W, by the dissipated energy per cycle, E.
Verification examples showing stress amplitude versus number of cycles (S-N diagram) are compared with experimental results. Also, experimental crack growth rate as a function of stress intensity factor (Paris-type equation) is compared with calculated results based on this method. Fatigue constants based on experimental data were not required in the computations. Limited comparison of predicted cycles to experimental results indicates good correlation. This work is significant in that it suggests a new and improved approach to problems of fatigue. Since fatigue behavior can be predicted using only uniaxial material tensile data, it holds out the promise of a reduced need for experimental work in the future.
Multiaxial Plasticity and Fatigue Life Prediction in Coiled Tubing
Authors: Tipton SM 
Published: March 2009

Coiled tubing is being used increasingly in the oil well drilling and servicing industry. Continuous steel tubing of structural dimensions (up to 89 mm or 3.5 in. in diameter) is wound onto a large-diameter reel for repeated deployment into and out of a well bore. The bending strain range associated with each wrap-unwrap cycle can exceed 3% with lives well below 100 cycles. During constant internal pressure fatigue testing, tubing has been observed to grow in diameter by as much as 30%.
This paper describes an analytical model to predict the fatigue behavior of coiled tubing subjected to variable pressure service conditions. The approach utilizes standard low-cycle fatigue data but requires additional experimental results from constant pressure fatigue testing. The algorithm is based on estimates of biaxial ratcheting from an incremental plasticity model using a hybrid associated flow rule, a modified kinematic hardening rule with multiple von Mises yield surfaces, and a specialized limit surface concept. An empirical damage parameter was formulated based on constant pressure fatigue data using mean and fluctuating von Mises equivalent strain components occurring throughout the life of a section of tubing. This parameter is used with the Palmgren-Miner definition of cumulative damage to track damage that is accumulating nonlinearly under constant or variable pressure histories. Modifications to standard incremental plasticity components and implementation assumptions used to apply the model are presented and discussed. The predictive capability of the model is demonstrated relative to data generated under constant and variable pressure histories.
Residual Operating Fatigue Lifetime—Estimation of Distribution Function
Authors: Kliman V , Füleky P , Jelemenská J 
Published: March 2009

Engineering structures often work under operating conditions in which the character of a load undergoes permanent change (different service-loading regimes). Such an operation is very frequent for transportation equipment, earthmoving machines, airplanes, etc. Considering that the service-loading process (time history of σ(t) stress or ∈(t) strain) at particular operating regimes exhibits in a majority of cases the stochastic nature, the question arises as to how to estimate the fatigue resistance of the structure under such service conditions. For this reason, a method was developed to evaluate such service from the viewpoint of fatigue reliability and to estimate the resulting fatigue lifetime in terms of probability interpretation.
The result of life calculation is the distribution function (DF) of the residual fatigue lifetime for the given loading regime. This DF reflects the loading history (sequence and nature of the previous loading regimes) and the random character of the interacting material and loading parameters. The DF obtained is in a good agreement with the experimental results. Finally, illustrative examples that reflect practical applications of this theory are presented.
Microstructure of Oxide Films Formed during the Waterside Corrosion of the Zircaloy-4 Cladding in Lithiated Environment
Authors: Pêcheur D , Godlewski J , Billot P , Thomazet J 
Published: March 2009

Zircaloy-4 cladding materials have been oxidized in a lithiated environment in autoclave and in out-of-pile loop tests. In such oxidation tests, a strong enhancement of the oxidation rate can occur depending on the water chemistry conditions and on the oxidation time. In this work, in order to improve our understanding of the detrimental effect of lithium on the corrosion behavior of the Zircaloy-4 cladding, the microstructure of oxide films has been characterized by TEM. Simultaneously, the lithium profiles and concentrations in the oxide layers have been determined using the SIMS technique, special attention being paid to the metal-oxide interface.
These analyses revealed the existence of a correlation between the oxidation rate, the oxide microstructure, and the lithium profiles in the oxide films. Before the occurrence of the strong acceleration of the oxidation rate, the whole oxide layer is mainly composed of columnar grains and the lithium has no access to the metal-oxide interface. On the contrary, after the occurrence of such a strong accelerated corrosion rate, the inner part of the oxide layer is composed mainly of equiaxed grains (up to the metal-oxide interface), lithium then having access to the metaloxide interface.
These experimental results are described extensively and analyzed, and their contribution to the understanding of the influence of lithium on the oxidation process of Zircaloy-4 cladding material is discussed as a function of an existing thin inner barrier layer at the metal-oxide interface.
The Influence of Temperature and Yield Strength on Delayed Hydride Cracking in Hydrided Zircaloy-2
Authors: Efsing P , Pettersson K 
Published: March 2009

To determine if delayed hydride cracking (DHC) can be the cause of the long axial cracks occasionally found in BWR fuel cladding, a systematic study of DHC in Zircaloy cladding has begun. In the initial stage of the project, a test technique was developed and applied to unirradiated samples of Zircaloy. The present study includes an investigation of the influence of the yield strength and temperature on the crack growth rate and the threshold stress intensity that must be exceeded before cracking begins.
Recrystallized (RXA) Zircaloy-2 has been compared to stress relief annealed (SRA) Zircaloy-2 with similar texture and composition. The results show that the crack propagation rate increases with increasing yield strength at similar stress intensity levels by as much as a decade when the yield strength is tripled. The maximum crack propagation rate measured in this study is ∼6 × 10-7 m/s. The threshold stress intensity, KIH, was found to decrease with increasing yield stress. The measured threshold values are in the range of 13.5 to 7.5 MPa. These figures are close to theoretically derived values using a critical fracture stress criterion of the hydrides as the limiting factor. The incubation period before cracking begins is found to be longer at 200°C than it is at 300°C.
In Situ Studies of Phase Transformations in Zirconium Alloys and Compounds Under Irradiation
Authors: Motta AT , Faldowski JA , Howe LM , Okamoto PR 
Published: March 2009

The High Voltage Electron Microscope (HVEM)/Tandem facility at Argonne National Laboratory has been used to conduct detailed studies of the phase stability and microstructural evolution in zirconium alloys and compounds under ion and electron irradiation. Detailed kinetic studies of the crystalline-to-amorphous transformation of the intermetallic compounds Zr3(Fe1-x,Nix), Zr(Fe1-x,Crx)2, Zr3Fe, and Zr1.5Nb1.5Fe, both as second phase precipitates and in bulk form, have been performed using the in situ capabilities of the Argonne facility under a variety of irradiation conditions (temperature, dose rate). Results include a verification of a dose rate effect on amorphization and the influence of material variables (stoichiometry x, presence of stacking faults, crystal structure) on the critical temperature and on the critical dose for amorphization.
Studies were also conducted of the microstructural evolution under irradiation of specially tailored binary and ternary model alloys. The stability of the ω-phase in Zr-20%Nb under electron and Ar ion irradiation was investigated as well as the β-phase precipitation in Zr-2.5%Nb under Ar ion irradiation. The ensemble of these results is discussed in terms of theoretical models of amorphization and of irradiation-altered solubility.
Influence of Iron in the Nucleation of ⟨c⟩ Component Dislocation Loops in Irradiated Zircaloy-4
Authors: de Carlan Y , Regnard C , Griffiths M , Gilbon D , Lemaignan C 
Published: March 2009

Under irradiation, the acceleration of growth of nuclear reactor components made of Zircaloy is clearly correlated to the presence of ⟨c⟩ component dislocation loops. In the early stages, these loops appear to be essentially located close to the intermetallic precipitates. At higher doses, when ⟨c⟩ component dislocation loops are observed all over the microstructure, analysis of the Zr matrix reveals an homogeneous iron content due to the dissolution of the precipitates. Thus, iron may play a significant role in the nucleation of ⟨c⟩ component dislocation loops.
A specific study has been performed on Zircaloy thin foils implanted with increasing amounts of iron. The conditions of nucleation and growth of these ⟨c⟩ component dislocation loops have been followed in a 1-MeV transmission electron microscope. The dose level for ⟨c⟩ component dislocation loop nucleation is weakly Fe-content dependent. However, their size and density increase with increasing iron implantation. These results are compared to direct observations made on irradiated reactor components. The role of iron on accelerated growth is then discussed.
Zircaloy-2 Lined Zirconium Barrier Fuel Cladding
Authors: Williams CD , Marlowe MO , Adamson RB , Wisner SB , Rand RA , Armijo JS 
Published: March 2009

The introduction of Zr-lined “barrier” fuel clad tubing by GE in the early 1980s to counter the pellet-clad interaction (PCI) failure mechanism in fuel for boiling water reactors provided a major improvement in fuel reliability and operational flexibility. While the frequency of fuel failures has been substantially reduced in the past decade, an increased tendency has been observed for failed fuel rods to exhibit post-failure degradation in the form of longer cracks that allow release of radioactive off-gas and contamination of the reactor coolant circuit with tramp fuel material. One factor involved in this degradation is hydriding of the cladding at a location remote from the initial perforation of the fuel rod. This local hydriding can lead to secondary crack initiation in the cladding when stressed by the fuel expansion accompanying a power increase.
A modification of Zr-lined “barrier” fuel clad tubing has been developed to retard post-failure local hydriding while retaining the proven PCI resistance of the high-purity sponge Zr barrier. By adding a thin inner layer of corrosion-resistant Zircaloy-2 bonded to the inner surface of the Zr-barrier tube, the resistance to internal corrosion and hydrogen generation in a perforated fuel cladding tube is made equivalent to that of an all-Zircaloy-2 tube. Tests show that the PCI mitigating capability of the Zr barrier is not compromised by this inner Zircaloy-2 liner. Materials considerations and manufacturing technology used to integrate this optional inner liner with other Zr barrier tubing properties and performance requirements are discussed with a summary of testing experience.
In-BWR and Out-of-Pile Nodular Corrosion behavior of Zry-2/4 Type Melts with Varying Fe, Cr, and Ni Content and Varying Process History
Authors: Ruhmann H , Manzel R , Sell H-J , Charquet D 
Published: March 2009

Zircaloy-based materials with constant tin content, a constant sum of Fe and Cr content, and different Fe/Cr ratios were manufactured from small ingots (6 kg) by forging, β- quenching, hot rolling, and cold rolling with two different annealing sequences resulting in two accumulated annealing parameters (A-parameter A = 0.1 E-18 and A = 10 E-18 h). To study the effect of Ni, chromium was substituted by nickel in one alloy. As a reference material standard, ASTM Zry-2 was manufactured in a similar way.
These materials were examined for precipitate size by TEM and for their out-of-pile corrosion behavior in 400°C steam up to 319 days and in 500°C steam up to 24 h in a static and in a refreshed autoclave. Furthermore, samples made from these alloys were irradiated in a commercial BWR for two years.
By comparing results from different out-of-pile tests to the data from in-pile irradiation, the following conclusions can be drawn: 1. The A-parameter influence with respect to corrosion is the dominant factor for out-of-pile and in-pile corrosion behavior. 2. The (Fe+Ni)/Cr ratio influences the corrosion resistance, especially at low values below about 5. The effect is found to be strong for low A-parameter materials under irradiation of two cycles comparable to the behavior found for the high A-parameter materials in out-of-pile tests. The nodular corrosion test reproduces the in-pile behavior found for the high A-parameter materials. 3. Nickel substituted for Cr reduces the effect of the A-parameter on corrosion. 4. Sizes of intermetallic precipitates depend on chemical composition and structure. Significant numbers of Zr3Fe particles are found only at Fe/Cr ratios above 5. These particles are significantly larger than the Laves phases. 5. The influence of the chemical composition of the precipitates to the corrosion behavior cannot be finally evaluated on the two-cycle irradiated samples. Further information is expected when the samples reach higher in-pile exposure.
An Experimentally Verified Finite Element Study of the Stress-Strain Response of Crack Geometries Experiencing Large-Scale Yielding
Authors: Panontin TL , Sheppard SD 
Published: March 2009

Large-strain, three-dimensional finite element analyses with incremental plasticity were performed for a variety of crack geometries to study local crack-tip stress-strain fields and associated global fracture parameters under conditions of large-scale yielding. The geometries analyzed include thin, single-edge crack tension, single-edge crack bending, and center-crack tension fracture specimens with varying crack depth (a/W) ratios. Two materials were investigated: a high-hardening, low-strength steel and a moderate-hardening, high-strength steel. Mesh refinement studies were performed to ensure convergence of the finite element predictions. The studies examine the effects of in-plane crack-tip element size, initial crack-tip radius size, and number of through-thickness layers on predicted distributions of crack-tip stress and plastic strain and predicted values of the J-integral and CTOD. In addition, the finite element predictions of specimen behavior were verified experimentally by direct measurements, namely load displacement, load longitudinal strain, and load CTOD, made during and following testing of the fracture specimens.
Representative results of the finite element analyses are presented and compared to previously published data where pertinent. Results from the mesh refinement studies and the verification testing are shown. Predicted trends among the specimens and materials in local distributions of crack-tip plastic strain, triaxiality, and opening stress as well as in global parameters, J-integral and m-factor, are discussed.
The finite element analysis results show that the deformation at the crack tip remains strongly three dimensional, with crack-tip stresses demonstrating near plane strain behavior on the midplane and near plane stress on the free surface, even in relatively thin specimens of finite size. Micromechanical models of ductile fracture based on plastic strain and triaxiality would predict that fracture begins straight ahead of the crack tip on the midplane and that the ductile fracture process occurs relatively close to the crack tip (e.g., within one CTOD). The J-integral was not found to decline monotonically from midplane to free surface but to increase near the free surface in most specimens.