bluuebunny/crossref_metadata_2025_split huggingface dataset:
Suitable Adjuvant to Maximize Trifloxysulfuron Efficacy and Early Assessment of Herbicide Efficacy Using Chlorophyll Fluorescence
Authors: Singh S , Singh M 
Published: May 2009

Abstract
Trifloxysulfuron 2.5, 5, and 10 g ai/ha mixed with non-ionic (0.25% Induce and X-77), organosilicone (0.1 % Kinetic and Silwet L-77), and crop oil concentrate (1 % Agridex and Meth-N-Oil) adjuvants was evaluated for efficacy, surface tension (ST), contact angle (CA), and chlorophyll fluorescence responses in redroot pigweed, prickly sida, and barnyard grass. The lowest ST and CA were recorded with L-77 mixed with trifloxysulfuron. Among the six adjuvants, ST and CA were highest with Meth-N-Oil; however, these differences did not greatly influence herbicide efficacy. No trifloxysulfuron-adjuvant antagonism was found for any weed species. Differences in activities were observed at 2.5 g/ha trifloxysulfuron with different adjuvants; however, activities were comparable when data were averaged over species and rates. All the adjuvants increased trifloxysulfuron efficacy; some differences were observed among the weed species, but adjuvants were equal in improving trifloxysulfuron efficacy. Redroot pigweed was more sensitive to trifloxysulfuron compared to barnyardgrass and prickly sida was least. Chlorophyll fluorescence 1, 4, 7, and 14 days after treatment (DAT) was not greatly inhibited by trifloxysulfuron mixed with different adjuvants. Reduction in chlorophyll fluorescence was recorded 4 DAT in barnyard grass, but the reduction was not proportionate to the mortality and lacked uniformity among different treatments.
Surfactant-Enhanced Release of Permethrin from a Cellulosic Granular Carrier
Authors: Stern AJ 
Published: May 2009

AbstractA study was conducted to determine whether the efficacy of pyrethroid insecticides, formulated with Biodac2 (an inert carrier granule derived from paper recycling waste) could be enhanced through the addition of surfactants. Thus, a series of formulations of permethrin on Biodac was prepared so that the effect of several nonionic surfactants on granule efficacy could be studied. To compare the efficacy of the formulations, the granules were tested on imported red fire ants, Solenopsis invicta, under laboratory conditions. Formulations with surfactant outperformed the control formulation (no surfactant) by a wide margin.
Development of a Fastener Structural Element Test for Certifying Navy Fastener Materials
Authors: Focht EM , L'Heureux BP , Roe C 
Published: May 2009

Abstract
New materials intended for use in critical U.S. Navy applications are evaluated by a Fracture Toughness Review Process (FTRP) for acceptability. In addition to developing data on the mechanical properties, fatigue life, and fracture toughness, the FTRP requires that a representative structural element test be performed to verify that the material can withstand plastic deformation at high loading rates in the presence of a detectable flaw. A Fastener Structural Element Test (FSET) has been developed to certify fastener materials such that the results of fracture mechanics testing on candidate alloys can be verified. The testing required the development of a suitable specimen that best represented a fastener, flaw seeding, and pre-cracking techniques, load and displacement measurement techniques suitable for high loading rates, and material performance acceptance criteria. The complete results of the testing on titanium alloy Ti-5AI-1Sn-1Zr-1V-0.8Mo (a.k.a. Ti-5111) and a Co-Ni-Cr-Mo-Al-Fe alloy will be presented along with the test methodology, data acquisition, and analysis details. The challenges encountered and areas that require further refinement will also be discussed.
Surface Roughness, Quasi-Static Fracture, and Cyclic Fatigue Effects on GFRP- and CFRP-Concrete Bonded Interfaces
Authors: Lawrence TO , Boyajian DM 
Published: May 2009

Abstract
The recently developed experimental fracture approach known as the Single Contoured-Cantilever Beam (SCCB) was used to characterize the interface bonds between concrete substrates and two varieties of FRP: glass and carbon (abbreviated GFRP and CFRP, respectively). Limited research has been performed concerning the FRP-concrete interface bond relative to three surface-roughness grades: low- (&lt;10 μm), moderate- (≈ 10–50 μm), and high- (&gt;50 μm), to establish the optimal formation for bonding. By use of the SCCB approach, Mode I critical strain energy release rate results are measured and quantified. Finally, considering that a majority of externally strengthened FRP concrete structures involves bridges and girders that are subjected to repeated (as opposed to static) loads, a preliminary study is conducted on cyclically fatigued FRP-concrete interfaces under varying load-ratio and frequency effects.
Detection of Crack Initiation by Observations of Free Surface Condition
Authors: Ichinose K , Yoshida S , Gomi K , Taniuchi K , Fukuda K , Ishii H 
Published: May 2009

Abstract
A simple method to detect crack initiation is presented. By polishing the surface of carbon steel structure properly and using the Lüders bands and orange peel as indicators for damage, it is possible to predict crack initiation with the naked eye. The initiation of the Lüders bands is the yellow light of the crack initiation, for instance, in the traffic signal, and orange peel is the red light. The relationship between the observed surface condition and the cyclic stress-strain characteristics is discussed.
Constraint CorrectedJ-R- Curve and Its Application to Fracture Assessment for X80 Pipelines
Authors: Zhu X-K , Leis BN 
Published: May 2009

AbstractSingle specimen J-R curve testing for X80 pipeline steel was conducted using single edge notched bend (SENB) and single edge notched tension (SENT) specimens with various crack lengths. Test data indicate that the J-R curves for this steel are strongly constraint dependent. To facilitate transferability of experimental J-R curves to those for actual cracked components, this paper develops a constraint corrected J-R curve for X80 steel. A modified J-Q theory that can consider the global bending stress influence is proposed so as to correctly quantify constraint effect on the crack-tip fields and the J-R curves. Results show that the modified J-Q solution can well match numerical crack-tip fields for bending specimens, with Q being a load-independent constraint parameter under large scale yielding. Based on the experimental data and numerical analysis, a constraint corrected J-R curve is formulated as a function of the parameter Q and crack extension Δa for X80 steel. A general procedure to predict J-R curves for actual cracked components is then outlined. Comparison indicates that the predicted J-R curves developed in this paper agree well with the experimental data for both SENB and SENT specimens. To demonstrate its application in failure assessment, the constraint corrected J-R curve for X80 steel is used to determine failure loads for a surface cracked pipeline. Reasonable agreement to available analytic solution is achieved.
Observations on Photo-Emission and the Process Zone of a Fatigue Crack
Authors: Patterson EA , Diaz FA , Yates JR 
Published: May 2009

Abstract
Cyclic loading of a solid material induces a cyclic temperature fluctuation. The thermal cycle is asynchronous with the loading cycle when the strains are elastic. This is commonly known as the thermoelastic effect. In differential thermography, a sensitive infrared camera is used to measure this temperature variation; typically of the order of a few tens of milliKelvin. Since the magnitude of the temperature variation is proportional to the dilational strain, values of the surface elastic stress can be derived. Recent advances in infrared camera technology and data processing algorithms have enabled values of effective stress intensity factor ranges and the location of fatigue cracks to be determined from temperature fluctuations around the crack tip on the specimen surface. Careful observation in the region near a crack tip reveals deviations from the asynchronous behavior of the photon signal relative to the load cycle. Phase shifts up to π/8 are commonly observed. The spatial distribution of these phase shifts exhibits characteristic features which are described and discussed. The features in this distribution appear to be associated with high elastic strain gradients, regions of plasticity and contact between the crack faces. Interpretation of the phase shift and its spatial distribution may lead to a better understanding of the mechanics of fatigue crack growth.
Temperature Dependence and Variability of Fracture Toughness in the Transition Regime for A508 Grade 4N Pressure Vessel Steel
Authors: Leax TR 
Published: May 2009

Abstract
A508 Grade 4N is a high nickel (3.4%) pressure vessel steel with a relatively high yield strength (585 MPa minimum for Class 1) and a relatively low transition temperature (47 J transition temperature of −29°C or below). Published fracture toughness data on this steel are nonexistent, and so they have not been included in prior assessments of the applicability of the Master Curve approach to pressure vessel steels. The purpose of this study is to compare the temperature dependence and data scatter for this steel with the behavior predicted by the Master Curve. The available database consists of approximately 800 fracture toughness tests on 51 material heats, some of which were given a temper embrittling heat treatment. As an additional basis of comparison, test data on A508 Grades 2 and 3, 1% nickel weld metal, and several high nickel (1.3–3.8%) steels (NiCrMo and NiCrMoV) were included in the assessment. Maximum likelihood techniques were used to fit the toughness data, and Monte Carlo methods were used to assess the observed distribution of Weibull slopes (related to the extent of variability). The results of this assessment show that the Master Curve provides a good description of the shape (temperature dependence) of the toughness curve for moderate and high transition temperatures. However, for heats with low transition temperatures below the range observed in other pressure vessel steels, the shape of the toughness curve deviates from the Master Curve. The lower the transition temperature, the larger the deviation from the Master Curve. Based on the test data, a model describing the behavior of A508 Grade 4N has been developed. This model also accurately describes the toughness behavior of the other pressure vessel steels included in this study. With respect to variability, the Weibull slope of A508 Grade 4N is consistent with the value of four prescribed by the Master Curve. However, the Weibull slope for the other pressure vessel steels included in this assessment is close to 3.4. This lower value of the Weibull slope, which indicates larger variability, is likely the result of material inhomogeneity.
Use of Miniaturized Compact Tension Specimens for Fracture Toughness Measurements in the Upper Shelf Regime
Authors: Lucon E , Scibetta M , Chaouadi R , van Walle E 
Published: May 2009

Abstract
In the nuclear field, the importance of direct fracture toughness measurements on reactor pressure vessel (RPV) materials has been nowadays widely recognized, as opposed to Charpy-based estimations. However, sample dimensions have to be kept small in order to optimize the use of available material (often in the form of previously broken Charpy specimens) or, in the case of new irradiations, make effective use of the limited space available inside irradiation facilities. One of the most appealing geometries for fracture toughness measurements is the miniature Compact Tension specimen, MC(T), which has the following dimensions: B = 4.15 mm, W = 8.3 mm, cross section 10 × 10 mm2. Four MC(T) specimens can be machined out of a broken half Charpy, and in the case of irradiation ten MC(T) samples occupy approximately the same volume as a full-size Charpy specimen. A comprehensive investigation is presented in this paper, aimed at assessing the applicability of MC(T) specimens to measure fracture toughness in fully ductile (upper shelf) conditions. In this study, 18 1TC(T) and 20 MC(T) specimens have been tested at different temperatures from three RPV steels and one low-alloy C-Mn steel. The results obtained clearly show that MC(T) samples exhibit lower fracture toughness properties, both in terms of initiation of ductile tearing (according to various test standards) and resistance to ductile crack propagation (J-R curve). The reduction of tearing resistance might be attributed to work hardening prevailing over loss of constraint in the uncracked ligament for a side-grooved specimen, or to the inadequacy of J-integral to represent ductile crack extension in very small specimens. Both arguments need to be verified with further investigations.
Analysis of Dynamic Fracture and Crack Arrest of an HSLA Steel in an SE(T) Specimen
Authors: Link RE 
Published: May 2009

AbstractA single edge notch tension, SE(T), specimen was used to measure the dynamic fracture toughness and the crack arrest toughness of a tough HSLA steel in the ductile-brittle transition region. The SE(T) specimen was considerably smaller (W = 152 mm) than wide-plate specimens that have been typically used in other crack arrest tests. A thermal gradient was applied across the ligament of the specimen to facilitate a brittle crack initiation in the low temperature region of the specimen. The cleavage crack propagated into warmer and, consequently, tougher material which led to crack arrest. Transient, three-dimensional, finite element analyses of the tests were performed to determine the dynamic fracture and crack arrest toughness of the steel. The analyses employed both linear elastic and visco-plastic constitutive models. Dynamic strain measurements recorded during the run-arrest event were used to determine the crack tip position as a function of time during the event. This information was used as a boundary condition for the analysis. The measured strains were compared with strains predicted by the finite element analysis to validate the model. The dynamic response of the specimen, the effect of crack speed on the driving force, and the evolution of crack tip plasticity during the run-arrest event are discussed.
Remediation Technology for Boron and Fluoride Contaminated Sediments Using Green Plants
Authors: Asada M , Parkpian P , Horiuchi S 
Published: May 2009

Abstract
Phytoremediation is the direct application of green plants and their associated micro-organism to stabilize or absorb contaminants from soils, sludge, sediments, surface water, or groundwater. Boron and fluoride were listed to the soil standards a few years ago in Japan; however, few researches have been reported about phytoremediation on the above elements. In this paper, the authors report the experimental results of accumulation and tolerance ability of green plants focusing on the fluoride and boron contamination. In the pot laboratory tests, the growth rate of Chinese cabbage was not affected by low fluoride concentration (&lt;15 mg/L) or low boron concentration (&lt;5 mg/L). In the hydroponics tests, fluoride content in both stems+leaves and roots increased 3–10 times higher than control. Fluoride is easy to be concentrated in the roots. Boron content in both stems+leaves and roots increased 1.2–1.5 times higher than control. Boron is easy to be concentrated in the upper portion. Especially, Phytolacca Americana, Ambrosia trifida L., and Commelina communis can accumulate boron with higher efficiency. The boron content in soil was 480–550 mg/kg, and the boron content in these grasses was 2–3 times higher than that in soil. These results show they can accumulate boron and fluoride, and phytoremediation can be adopted for relatively lower contamination.
Optical Tests on the Slow Release of Biogenic Gas Bubbles in Sediment
Authors: Dyer M 
Published: May 2009

Abstract
The anaerobic decomposition of organic matter in marine or fresh water sediments can generate methane, carbon dioxide, hydrogen sulphide, and hydrogen as biogenic gases. In addition, innovative technologies are being used to remediate contaminated sediments and groundwater by releasing biogenic gases from the fermentation of carbon substrates as electron donors. Both scenarios can result in large discrete gas bubbles being present in sediment, which can affect aqueous permeability and mechanical strength. Furthermore the movement of gas bubbles can affect bioavailability as electron donors. In order to investigate bubble dispersion and movement in sediments, a series of novel optical experiments were carried out to observe the release and movement of discrete bubbles in artificial coarse-grained sediment. The results showed that buoyancy-induced movement depended on the clustering together of individual bubbles to achieve a critical depth of gas pocket to overcome the capillary force acting across the pore throat between sediment grains.
Development of Filtration System for Removal of Contaminated Suspended Solids in an Enclosed Sea Area
Authors: Fukue M , Minato T , Uehara K , Sato Y , Inoue T , Yamasaki S 
Published: May 2009

Abstract
The quality of seawater can be improved by removing suspended solids (SS) that may adsorb hazardous substances, such as heavy metals, polycyclic aromatic hydrocarbons, bacteria, etc. In this study, two types of filtration systems are developed in order to remove SS from sea, lake, and pond water. The first filtration system is a larger system for the rapid reduction of SS, and the other can be used for a slower removal of SS. The features of the smaller system are that solar panels were used as the power source and clogging of the filter can be prevented by a reverse water flow with an automatic control. Long-term in situ experiments showed that SS were almost completely removed by filters made of granular materials. Removal capacity was dependent primarily on both the sectional area of the filter and the relationship between the permeability of filter materials and the size of the SS. With treatment, good water quality was obtained in terms of SS, chemical oxygen demand and concentrations of nutrients.
A Combined Method: Precipitation and Capping, to Attenuate Eutrophication in Canadian Lakes
Authors: Galvez-Cloutier R , Leroueil S , Allier D , Locat J , Arsenault S 
Published: May 2009

AbstractEutrophication is a natural phenomenon, unfortunately amplified and accelerated by human activities. Phosphorus and nitrogen are the principal nutrients responsible for eutrophication. Their excess in the environment, of domestic and agricultural origins, represents an important toxicological risk for the users of water. These excessive nutrients cause algae overgrowth and excess oxygen consumption, which leads to anoxic waters, production of toxins (such as those produced by canobacteria), and the production of pollutant gases. Excess nutrients and dead biomass settles at the bottom of the lake together with other trace contaminants such as toxic metals that are trapped within bottom sediments. Seasonally, the sediments release nutrients and contaminants that need to be mitigated in order to prevent eutrophication and overall water contamination. In Quebec and in Canada several lakes suffer from this problem and solutions have been divided in preventive practices (better runoff controls, protection of shores, elimination of leaking domestic septic tanks) and rehabilitating practices (oxygenation of water, precipitation of nutrients, dredging of sediments or capping). This paper will present recent advances in the development of a combined rehabilitating technique: Precipitation of phosphorous and capping of contaminated sediments. The paper includes: a recent literature review; phosphorous precipitation experiments using alum under optimized parameters; capping design considerations and theory; as well as the results of an experimental simulation of capping using a composite liner calcite/sand.
Development of an In Situ Biodegradation Technology by Using Anaerobic Micro-Organisms for Sediment Contaminated with Dioxins
Authors: Hata T , Kurisu F , Yagi O , Mori H , Kuwano R , Kohashi H 
Published: May 2009

Abstract
In this paper, an in situ bioremediation method is proposed for dioxin contaminated sediments and its efficiency is assessed in laboratory tests including microbial analysis. The main outcomes of this research are (1) Proposal of an in situ bioremediation method using anaerobic micro-organisms monitored by molecular microbial techniques. (2) It was shown that the proposed method can reduce dioxin concentrations and can increase populations of the dehalogenating micro-organism (Dehalococcoides sp.). (3) It was further shown that the dioxin degradation processes can be monitored using polymerase chain reaction (PCR) denaturing gradient gel electrophoresis and real-time PCR. Microbial analysis using molecular techniques was useful for the monitoring and management of the sediment remediation process.
Monitoring Heavy Metal Transport in Aquifer Based on Electrical Property Measurements
Authors: Kim Y , Oh M , Bang S , Park J 
Published: May 2009

Abstract
Monitoring the movement of subsurface contamination using the electrical properties of soils has the economical merits of providing continuous and automated soil profiles. However, identification on the sensitivity of this property in reflecting both the presence and concentration of different contaminant types has been validated for soils under static conditions. For application, electrical properties of soils must be verified under an active state where contaminant migration by means of groundwater migration is considered. The objective of this study is to provide the groundwork required in applying the electrical properties of soil as a means of monitoring contaminant migration by performing column tests. Two parameters representing the electrical property of materials are examined in this study; the electrical resistivity and the dielectric constant. Measurements for these parameters are performed at a low frequency range where the spatial polarization takes place and increases the sensitivity of the electrical property against the presence of the contaminant. In order to detect the contaminant movement in the subsurface level, electrical measurements were performed during column tests for saturated sand and weathered granite soil. In addition, three different contaminants (aluminum, lead, and cadmium) were selected to groundwater contaminated by heavy metals. As a result, the relationships between the contaminant migration against the electrical resistivity, real, and imaginary parts of the dielectric constant were derived for different time intervals during the column tests.
Development of an Acoustical Method for Measuring the Transition Layer of Surficial Marine Sediments
Authors: Kimura M , Ishida K 
Published: May 2009

Abstract
A new acoustical method for measuring the physical properties for the transition layer of surficial marine sediments is proposed. In the proposed method, the frequency characteristics of the reflection coefficients for the acoustical normal incidence are utilized. The frequency characteristics of the reflection coefficients are influenced by the depth dependence of the porosity and the density. First, the relationships between the frequency characteristics of the reflection coefficients and the porosity variation with the depth are theoretically shown using Ocean Acoustics and Seismic Exploration Synthesis (OASES) (Biot-Stoll model). Then, the frequency characteristics of the reflection coefficients are measured in water tank and in situ. The measured results are compared with the calculated results using OASES (Biot-Stoll model). Finally, the usefulness of this method is demonstrated.