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about 19%. Analysis of variance of data obtained is carried out at P-value ≤ 0.05. Fabric finished using recipe Ⅰ (Sanitized~R T99-19 alone), recipe Ⅱ (Sanitized~R T99-19 with Siligen~R TX2490) or recipe Ⅲ (Sanitized~R T99-19 ...
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about 19%. Analysis of variance of data obtained is carried out at P-value ≤ 0.05. Fabric finished using recipe Ⅰ (Sanitized~R T99-19 alone), recipe Ⅱ (Sanitized~R T99-19 with Siligen~R TX2490) or recipe Ⅲ (Sanitized~R T99-19 and Siligen~R TX2490 with Arkofix~R NG-ET) manifests inhibition clear zones towards Staphylococcus aureus and Pseudomonas aeruginosa a bacteria, as a result of the physically bound portion of 'dimethyl-tetradecyl-[3(trimethoxysilane-propyl] ammonium chloride (active ingredient of Sanitized~R T99-19) and/or its adduct with Arkofix~R NG-ET' that leaches out of the fabric. However, this portion cannot tolerate repeated laundering up to 10 cycles. Finishing the fabric using Sanitized~R T99-19 at a concentration of 5 g/L can acquire the fabric very high values of reduction in bacterial count'even after 25 washing cycles, regardless of treatment recipe. Below 5 g/L in recipe Ⅲ, the fabric fails to manifest total reduction in bacterial count after 10 washing cycles. Reduction in bacterial count is remarkably improved by increasing the concentration from 5 to 10 g/L in recipe Ⅲ, regardless of washing cycles.
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Mercury is a largely uncontrollable heavy metal contaminant in that it is globally ubiquitous, and environmentally persistent. The element has the potential for global mobilization following liberation from environmental stores, w...
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Mercury is a largely uncontrollable heavy metal contaminant in that it is globally ubiquitous, and environmentally persistent. The element has the potential for global mobilization following liberation from environmental stores, which can occur as a consequence of either anthropogenic activities or natural processes. Furthermore, organic forms like methylmercury accumulate in biological tissues with an exceptionally long biological half-life, facilitating the magnification of this toxin along trophic food chains. Bioaccumulation is particularly evident in aquatic environments, in which long-lived piscivorous fishes and marine mammals are reported with a mercury burden one-million times that of the surrounding water body, typically attaining mercury burdens exceeding 1 μg g~(-1). Mercury levels in other seafood, however, are typically reported in the range of 0.1 to 0.2 μg g~(-1) and usually less then 0.5 μg g~(-1). The primary source of human exposure to environmental mercury is through seafood consumption. The dangers associated with the consumption of large amounts of methylmercury accumulated in seafood are well recognized from past poisoning incidents, in which fish with mercury burdens in the range of 9 to 24 μg g~(-1) were consumed. Nevertheless, the toxicological consequence of chronic low-level mercury exposure from habitual seafood consumption is an area of contention. This review discusses the mechanisms of mercury accumulation and distribution in fish tissues and the toxicological consequences of mercury exposure from seafood consumption with regard to international safety guidelines.
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Real-time hybrid testing is an attractive method to evaluate the response of structures under earthquake loads. The method is a variation of the pseudodynamic testing technique in which the experiment is executed in real time, thu...
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Real-time hybrid testing is an attractive method to evaluate the response of structures under earthquake loads. The method is a variation of the pseudodynamic testing technique in which the experiment is executed in real time, thus allowing investigation of structural systems with time-dependent components. Realtime hybrid testing is challenging because it requires performance of all calculations, application of displacements, and acquisition of measured forces, within a very small increment of time. Furthermore, unless appropriate compensation for time delays and actuator time lag is implemented, stability problems are likely to occur during the experiment. This paper presents an approach for real-time hybrid testing in which time delay/lag compensation is implemented using model-based response prediction. The efficacy of the proposed strategy is verified by conducting substructure real-time hybrid testing of a steel frame under earthquake loads. For the initial set of experiments, a specimen with linear-elastic behavior is used. Experimental results agree well with the analytical solution and show that the proposed approach and testing system are capable of achieving a time-scale expansion factor of one (i.e., real time). Additionally, the proposed method allows accurate testing of structures with larger frequencies than when vising conventional time delay compensation methods, thus extending the capabilities of the real-time hybrid testing technique. The method is then used to test a structure with a rate-dependent energy dissipation device, a magnetorheological damper. Results show good agreement with the predicted responses, demonstrating the effectiveness of the method to test rate-dependent components.
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In this paper, it is proved the stability of rational methods for the time discretization of abstract well-posed second order in time problems where the differential operator generates a cosine function. The particular case of ope...
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In this paper, it is proved the stability of rational methods for the time discretization of abstract well-posed second order in time problems where the differential operator generates a cosine function. The particular case of operators associated to a sesquilinear form is studied in detail. These rational methods are suitable for these problems and they can be defined, for example, by using Runge-Kutta-Nystroem methods.
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The motion of a vortex domain wall in a ferromagnetic strip of submicron width under the influence of an external magnetic field exhibits three distinct dynamical regimes. In a viscous regime at low fields the wall moves rigidly w...
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The motion of a vortex domain wall in a ferromagnetic strip of submicron width under the influence of an external magnetic field exhibits three distinct dynamical regimes. In a viscous regime at low fields the wall moves rigidly with a velocity proportional to the field. Above a critical field the viscous motion breaks down, giving way to oscillations accompanied by a slow drift of the wall. At still higher fields the drift velocity starts rising with the field again but with a much lower mobility dv/dH than in the viscous regime. To describe the dynamics of the wall, we use the method of collective coordinates that focuses on soft modes of the system. By retaining two soft modes, parametrized by the coordinates of the vortex core, we obtain a simple description of the wall dynamics at low and intermediate applied fields that applies to both the viscous and oscillatory regimes below and above the breakdown. The calculated dynamics agrees well with micromagnetic simulations at low and intermediate values of the driving field. In higher fields, additional modes become soft and the two-mode approximation is no longer sufficient. We explain some of the significant features of vortex-domain-wall motion in high fields through the inclusion of additional modes associated with the half antivortices on the strip edge.
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The transition from Java 1.4 to Java 1.5 has provided the programmer with more flexibility due to the inclusion of several new language constructs, such as parameterized types. This transition is expected to increase the number of...
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The transition from Java 1.4 to Java 1.5 has provided the programmer with more flexibility due to the inclusion of several new language constructs, such as parameterized types. This transition is expected to increase the number of class clusters exhibiting different combinations of class characteristics. In this paper we investigate how the number and distribution of clusters are expected to change during this transition. We present the results of an empirical study were we analyzed applications written in both Java 1.4 and 1.5. In addition, we show how the variability of the combinations of class characteristics may affect the testing of class members.
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A continuum mechanics model is established for hydrogen storage in single- and multi-wall carbon nanotubes (CNTs) and the bundle of single-wall CNTs. The model accounts for the deformation of CNTs, and van der Waals interactions a...
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A continuum mechanics model is established for hydrogen storage in single- and multi-wall carbon nanotubes (CNTs) and the bundle of single-wall CNTs. The model accounts for the deformation of CNTs, and van der Waals interactions among hydrogen molecules and between hydrogen and carbon atoms. The analytical expressions of hydrogen storage (number of hydrogen molecules per unit volume) in CNTs are obtained, and are validated by atomistic simulations. CNTs are categorized as tiny, small, medium and large CNTs; tiny CNTs cannot achieve the goals of hydrogen storage (62 kg/m~3 and 6.5 wt% of hydrogen set by the US Department of Energy) without fracture; small CNTs are strained during hydrogen storage; medium CNTs can achieve the above goals without the strain and do not self collapse; and large CNTs may self collapse upon the release of hydrogen.
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The reflood rate in a core is an important parameter for core cooling during a large-break loss-of-coolant-accident (LBLOCA) reflood period, and it strongly depends on the thermal-hydraulic conditions in the down-comer. During thi...
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The reflood rate in a core is an important parameter for core cooling during a large-break loss-of-coolant-accident (LBLOCA) reflood period, and it strongly depends on the thermal-hydraulic conditions in the down-comer. During this period, downcomer boiling has an important influence on the transient behavior of a postulated LBLOCA because it can degrade the hydraulic head in a downcomer and consequently affect the reflood flow rate for core cooling. Although it is recognized that downcomer boiling is critical to correctly predict the reflood phenomena of an LBLOCA transient, especially for a direct vessel injection adapted system like the advanced power reactor APR1400, the amount of experimental data and code assessment in this area is relatively limited. To improve the state of knowledge relative to downcomer boiling, a test program at the Downcomer Boiling (DOBO) facility is progressing for the reflood phase of a postulated LBLOCA. The DOBO facility was designed to meet a full scale for the height and gap of a reactor downcomer. The DOBO test revealed a strong multidimensional boiling behavior, which induces the need for performance evaluation of the best-estimate codes that are used to analyze a nuclear reactor's thermal-hydraulic safety, since they have mostly been used for one-dimensional system behavior. In this study, RELAP, MARS, and TRACE are evaluated by using measured two-phase-flow data. Based on the assessments, the modeling capability and weak points of the safety analysis codes are addressed for multidimensional downcomer boiling phenomena. Two models for a downcomer are considered to assess the codes for the DOBO tests, which are also applied to a plant analysis.
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This study evaluated the performance of two water quality models in accordance to specific tasks designated in the USDA Agricultural Research Service Conservation Effects Assessment Project. The Soil and Water Assessment Tool (SWA...
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This study evaluated the performance of two water quality models in accordance to specific tasks designated in the USDA Agricultural Research Service Conservation Effects Assessment Project. The Soil and Water Assessment Tool (SWAT) and the Annualized Agricultural Non-Point Source (AnnAGNPS) models were applied uncalibrated to the Cedar Creek watershed within the St. Joseph River watershed in northeastern Indiana to predict streamflow and atrazine losses. In order to ultimately assess the benefits of conservation practices in agricultural watersheds (which is one of the major goals of the Conservation Effects Assessment Project), proper application of the SWAT and AnnAGNPS models is essential including baseline comparisons made in an uncalibrated mode aimed at eliminating bias due to parameter optimization. Streamflow prediction results show that SWAT model performance was superior to AnnAGNPS, with SWAT model efficiency values ranging from 0.66 to 0.25 and AnnAGNPS model efficiency values ranging from 0.13 to -2.06 for monthly and annual streamflow, respectively. For uncalibrated conditions, neither model was able to adequately simulate atrazine loss concentrations. Overall results suggest that for Conservation Effects Assessment Project modeling applications at the Cedar Creek watershed scale in this study, the use of the SWAT model would be preferable to AnnAGNPS in terms of overall model performance and model support technology (e.g., model interface and documentation).
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Impacts of watershed scale conservation practice adoption on sediment, nutrient, and pesticide losses and adjacent stream biota are not well understood. The objective of this study was to examine the suitability of selected paired...
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Impacts of watershed scale conservation practice adoption on sediment, nutrient, and pesticide losses and adjacent stream biota are not well understood. The objective of this study was to examine the suitability of selected paired watersheds to quantify hydrology, chemical, and ecology effects of conservation practice implementation for channelized and unchannelized watersheds in Upper Big Walnut Creek watershed, Ohio. Channelized watersheds were more similar in watershed characteristics than the unchannelized watersheds. One hydrology, eight water chemistry, and five fish community response variables were measured. Most response variables in both watershed pairs were moderately correlated (r > 0.6), but the minimum percent change required to detect a response difference was greater for the unchannelized watersheds. Detectable temporal trends in the difference between like response variables for the channelized and unchannelized watershed pairs were minimal. These results validate the paired watershed design and suggest that conservation practice induced changes in hydrology, water quality, and fish communities can be quantified.
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