bluuebunny/crossref_metadata_2025 huggingface dataset:
Type S Portland Cement-Lime Mortar as a Low-Lift Grout
Authors: Biggs David T. , Thomson Margaret L.
Published: January 2009

Specification for Grout for Masonry, ASTM C 476, allows grouts to be specified by a proportion method using the cementitious materials of portland cement, blended cement, hydrated or putty lime (with a 1/10 by volume limit), and aggregate. There is no limitation on slump values in ASTM but industry standards recommend a slump of 8 to 11 in. (203 to 279 mm). A second method of specifying grout is by its properties with a minimum 28-day compressive strength value of 2000 psi (13 790 kPa). It is not an uncommon practice, however, for masonry contractors to use portland cement-lime mortars in low-lift (less than 5 ft [1.52 m] height) applications at a consistency of bedding mortar or a pourable consistency. According to ASTM C 476, this application would neither meet the proportion specification because of too much lime nor the property specification because of too low a slump. This study, investigating the comparative compressive strength properties and reinforcement pull-out strength of Type S and Type N ASTM C 270 proportioned cement-lime mortars, ASTM C 476 grout, and grout with comparable hydrated lime proportions to a Type S mortar, supports the following conclusions: • Type S portland cement-lime mortar at a bedding mortar consistency will perform as grout in specific low-lift grouting applications. • Type S portland cement-lime mortar at a pourable consistency will perform as grout in specific low-lift grouting applications. • Type M portland cement-lime mortar at a bedding mortar consistency or pourable consistency could also be used as grout in specific low-lift grouting applications.
Modeling the Heat, Air, and Moisture Response of Building Envelopes: What Material Properties are Needed, How Trustful Are the Predictions?
Authors: Hens Hugo S. L. C.
Published: January 2009

The physical models which form the basis for the different software tools used to predict heat, air, and moisture response of building envelopes seem quite diverse. For example, various “potentials” are used, and each individual potential demands apparently different properties. Anyhow, when digging into the physics and confronting the theory with what is measurable, then an array of eight basic material characteristics appear, all backed by an experimental rationale. Adapting that array to the potentials in use is not a question of creating new properties but of implementing the basic ones into potential-adapted expressions. A different problem, however, is that these basic properties are macroscopic in nature, i.e., represent the complexity of a material at the micro-scale by one single “average” number. That introduces restrictions as to the use of the property values measured experimentally. Hence, those restrictions are typically mixed up with the inability of the actual software packages to represent reality in full detail. Too many times, assumed incorrectness of the property values are blamed for causing the differences found between the predicted and real heat, air, moisture response of envelope parts. That inability, instead, should convince researchers and building engineers that the way to gain a well balanced understanding of the heat, air, and moisture response of envelopes is not by modeling only but by combining modeling with testing and field experience.
Fatigue Crack Growth Analyses of Aerospace Threaded Fasteners—Part III: Experimental Crack Growth Behavior
Authors: Olsen Kirk W. , Rimnac Clare M.
Published: January 2009

Because fatigue crack growth in a threaded fastener can cause the loss of an aircraft, damage tolerant analyses are required. Because designers commonly perform crack growth analyses on stainless steel fasteners with scant data or simplifying assumptions, or both, the objective of this research was to determine the stress intensity multiplication factor (Y) in the threads of a nut loaded, stainless steel, aerospace, roll-threaded bolt under tensile fatigue conditions as the nondimensionalized crack depth (a/d) approaches zero. Y(a/d) can then be used to improve the accuracy of fatigue crack growth life estimations. Unflawed and flawed aerospace bolts were fatigue tested at a maximum stress (S) ranging from the ultimate tensile strength (UTS) to the surface endurance limit of the test bolt and at several loading ratios of 0.1⩽R⩽0.9. Data collection from the fracture surfaces yielded crack front shape characterization and striation spacing. The shape of the crack front in the unflawed and flawed test bolts was different and both changed as the crack grew. Fifty-one striation spacing measurements ranging from 5.6×10−5 to 7.9×10−4 mm were found at crack depths of a/d>0.035. These striation measurements were directly related to crack growth rates so that stress intensity factor ranges (ΔK) and in turn Y(a/d) could be estimated.
Fatigue Crack Growth Analyses of Aerospace Threaded Fasteners—Part II: Material/Stress State and Bolt Strength
Authors: Olsen Kirk W. , Rimnac Clare M. , Ferrell Douglas W. , Garrett Carl E.
Published: January 2009

Because fatigue failure in a threaded fastener can cause the loss of an aircraft, fatigue strength analyses are required. Understanding the material and stress state within the threads of the bolt was one objective of this research because this information would provide insight into the cyclic strength of the bolt. The second objective was to determine the fatigue strength in the threads of a nut-loaded, stainless steel, aerospace, roll-threaded bolt under tensile fatigue conditions. The resulting S-N curves can then be used to improve the accuracy of fatigue life estimations. X-ray diffraction was used to determine the residual stress in the thread root of the test bolts while light and scanning electron microscopy were used to image the thread root grain structure. Unflawed and flawed aerospace bolts were fatigue tested at a maximum stress (S) ranging from the ultimate tensile strength (UTS) to the surface endurance limit of the test bolt and at several loading ratios between 0.0<R<1.0. The cycles to failure (Nf) and corresponding stress (S) were recorded for 143 specimens.

The thread root, residual compressive stress reached 65 % of the bolt UTS. The residual stresses are the result of the cold-rolled thread forming and grain distortion/alignment. The S-Nf plots showed a 10 % reduction in allowable fatigue stress due to a flaw. The unflawed bolt S-Nf curves showed typical variation with loading ratio (R) and reductions in fatigue strength below that of the fatigue strength of the bolt material (unnotched).
Fatigue Crack Growth Analyses of Aerospace Threaded Fasteners—Part I: State-of-Practice Bolt Crack Growth Analyses Methods
Authors: Olsen Kirk W.
Published: January 2009

To perform accurate crack growth analyses on roll-threaded fasteners, aerospace designers are required to estimate fatigue crack growth in the threads of a nut-loaded, roll-threaded bolt under tensile fatigue conditions. Threaded fasteners are difficult to analyze due to their asymmetrical geometry and fastener fatigue crack growth data are scant, especially for nondimensionalized crack depths of (a/d)<0.1. Thus, aerospace designers must make simplifying assumptions and perform analyses with presumably conservative methods. History has shown that improper design assumptions/methods on other critical aircraft components has led to catastrophic failures. Because many fasteners are flight safety critical, their analyses must be accurate. Five leading methods to determine the stress intensity multiplication factor, Y(a/d), for threaded fasteners, based on experimental data, analytic equations, or FE methods, or a combination there of, are compared. By comparing and considering these five methods together, critical observations are made to guide future research based on these state-of-practice Y(a/d) solution methods.
Fatigue Crack Growth Analyses of Aerospace Threaded Fasteners—Part IV: Numeric Analyses and Synthesis of All Results
Authors: Olsen Kirk W. , Rimnac Clare M. , Wawrzynek Paul A. , Carter Bruce J.
Published: January 2009

The objective of this research was to determine the stress intensity multiplication factor (Y), as a function of the nondimensionalized crack depth (a/d), in the threads of a nut-loaded, aerospace, roll-threaded bolt under tensile fatigue conditions as a/d approaches zero. The proposed Y(a/d) solution can be used to improve fatigue crack growth life estimations. The research objectives were achieved through bolt material/stress state characterization, cyclic testing, and numeric modeling. The fracture analysis code FRANC3D was used because it could predict crack front shape and stress intensity factor (K). The numeric models predicted a changing crack front and stress intensity factors similar to the test data. The numeric studies accounted for the residual stresses measured by X-ray diffraction within the thread root of the test bolts. The FRANC3D model predicted Y(a/d) at shallow crack depths in the range of 0.01<a/d<0.11. By curve fitting the numeric and experimental data, a new Y(a/d) solution was determined: Y(a/d)=3079(a/d)6−6779(a/d)5+5757(a/d)4−2340(a/d)3+478.6(a/d)2−46.94(a/d)+2.506. The use of this Y(a/d) solution produces conservative crack growth life estimates relative to popular/benchmark methods. Based on test bolt fatigue data, greater accuracy may be possible with this Y(a/d) solution.
Component Durability and High Mileage Performance of a Full Carboxylate Coolant in Heavy Duty Diesel (HDD) Engines
Authors: Fritz Paul O. , Bartley Leonard S. , Pellet Regis , Moser Virginia , Ulabarro Carmen
Published: January 2009

Performance of a full carboxylate coolant has been demonstrated in engine bench cavitation testing, fleet testing, and post fleet testing coolant corrosion tests. Performance in the proposed ASTM “Heavy Duty Cavitation Test” was established and found to satisfactorily exceed performance limits. Fleet testing of a full carboxylate coolant technology in Class 8 trucks, using Caterpillar C-12 engines demonstrated minimal inhibitor depletion to 400 000 miles under controlled zero coolant top-off conditions with no refortification. In a second fleet, vehicles accumulated high mileages under real world conditions. In this test, Caterpillar 3406E engines were torn down and inspected demonstrating extended corrosion protection and superior component durability to beyond 700 000 miles, without the addition of supplemental coolant additives or extenders. Coolants from these vehicles were removed and tested in the laboratory to verify their extended life properties.
Internal Probe to Detect Defects from Cascades—In-situ Ion Irradiation Experiments Revisited
Authors: Ishino Shiori , Sekimura Naoto , Abe Hiroaki
Published: January 2009

Our understanding of the evolution of extended defects during irradiation has progressed considerably since 1990 following the proposal of production bias by Bachu Singh and C. H. Woo. One of the important phenomena underlying this concept is that self-interstitials and interstitial clusters can migrate a long distance via one-dimensional motion. There have been a number of indirect experimental evidences supporting this mode of migration. However, the direct evidence has not necessarily been sufficient. In this paper, we revisit our former experimental results of in-situ observation of ion irradiation damage from the stand point of an internal probe for detecting point defect fluxes in an irradiation environment or those coming from nearby cascades. Surfaces, giving rise to specimen size effects, preexisting dislocations, intentionally preintroduced vacancy loops with stacking fault, irradiation induced vacancy clusters and loops, precipitates and precipitate-matrix interfaces, etc., are utilized to monitor the influx of point defects, particularly those of interstitials nature. Some of the reanalysis of the former results will be presented.
Fundamental Frequency Testing of Segmental Retaining Wall (SRW) Specimens: Test Considerations
Authors: Chan Cesar , Carino Stephen , Durham Michael , Hover Kenneth C.
Published: January 2009

As part of a larger investigation on freeze-thaw durability of masonry segmental retaining wall (SRW) units, specimens of various geometries were extensively evaluated for their resonant frequency prior to freeze-thaw exposure. These pretest trials were conducted to assess the applicability of the impact resonance method on these specimens, to identify factors affecting test result interpretation, and to obtain initial values for future comparison with values after freeze-thaw cycling. The importance of correctly identifying resonant frequencies corresponding to different modes of vibration of the specimen is highlighted, and methods to achieve this in the laboratory are discussed. The effects of specimen moisture content variations, temperature, and sampling parameters on resonant frequency are also presented.
Investigation of Radiation Transport Modeling Trends in the WSMR Fast Burst Reactor Environments
Authors: Sparks M. H. , Sallee W. W. , Flanders T. M.
Published: January 2009

Radiation transport calculations provide the backbone for the spectrum characterization used to support experimenters at research reactors. The radiation transport calculations provide a priori neutron spectra used in least squares spectrum adjustment. In addition, calculations are often the sole source of baseline neutron spectra data when an experimental test object substantially perturbs the free-field spectrum. It is crucial that analysts provide high fidelity uncertainty quantification for the spectrum calculations. This is an investigation of systematic trends as the distance to the source is varied in calculated spectra at a fast burst facility. A comparison of ratios is designed to highlight trends in the C/E ratios that may shed light on deficiencies in the transport cross sections or sensitivities to the details of the facility modeling. Initial comparisons of the latest IRDF-2002 [1] dosimetry cross section library to the SNL RML [2] cross section library have been made and are discussed.
Towards Crack Arrest Testing Using Miniature Specimens
Authors: Scibetta M. , Link R. , Schuurmans J. , Lucon E.
Published: January 2009

Crack arrest is an important concept that can be useful to guarantee the safety of reactor pressure vessels. In case of a pressurized thermal shock, a postulated crack can initiate and arrest due to a decrease in driving force combined with an increase in material toughness due to the thermal and neutron embrittlement gradient along the thickness. Due to the size of the specimen and the difficulty in obtaining valid results according to the ASTM E1221-06 standard, “Standard Test Method for Determining Plane-Strain Crack-Arrest Fracture Toughness, KIa, of Ferritic Steels,” current efforts to develop this technique for irradiated materials are very limited. However, advances in dynamic fracture modeling and elastic-plastic fracture mechanics open the possibility of using miniature crack arrest specimens. We have developed a stiff setup to perform crack arrest tests on precracked Charpy (PCCv) specimens. Different strategies were evaluated to provide enough reduction in driving force to produce arrest. Special attention is given to the starter notch and different starter notch preparations are investigated: precracking, chevron, and brittle weld. Testing configurations were found that guarantee crack arrest with sufficient remaining ligament. The dynamic loading condition is investigated experimentally using strain gauges. Finite element calculations of an arresting crack are also performed in order to provide more insight of the loading after the crack arrest event. Although it is not yet possible to derive the arrest fracture toughness from the PCCv testing, results are encouraging and open new perspectives in the field of crack arrest determination.
Evaluation of Hydride Reorientation Behavior and Mechanical Properties for High-Burnup Fuel-Cladding Tubes in Interim Dry Storage
Authors: Aomi Masaki , Baba Toshikazu , Miyashita Toshiyasu , Kamimura Katsuichiro , Yasuda Takayoshi , Shinohara Yasunari , Takeda Toru
Published: January 2009

The hydride stress reorientation behavior and the mechanical properties of irradiated cladding tubes were investigated to evaluate the high-burnup fuel-cladding tube properties in interim dry storage. As for the boiling water reactor (BWR) Zircaloy-2 (Zry-2) cladding, the hydride reorientation to the radial direction occurred at relatively low hoop stresses during the hydride reorientation treatment (HRT), such as less than 70 MPa. The increase of reorientation with hoop stress was not monotonic for the specimens in which a part of the hydrides remained precipitated at the HRT temperature, such as the case for 50GWd/t type cladding at a 300°C HRT. The degree of reorientation depended on the HRT solution temperature rather than on the estimated temperature at which the hydride precipitation occurred under the relatively moderate HRT conditions. In the relatively low cooling rate HRT, the hydride preferential precipitation in the Zr liner increased for Zr lined cladding compared to that in a relatively high cooling rate. The ductility of the specimens after the 300°C HRT showed relatively good correlation to the Polymax index which reflects the length or continuity of the hydrides regardless of their orientation. The ductility of the specimens after the 400°C, 0 MPa, 30°C/h HRT increased in ring compression testing at room temperature compared to no HRT (as-irradiated) specimens, and it indicated recovery of irradiation damage occurred at the 400°C annealing temperature and affected the ductility of the irradiated Zry-2 cladding. As for the pressurized water reactor Zircaloy-4 cladding, little increase in the radial hydride ratio occurred in a 100 MPa, 340°C or less HRT. On the other hand, the amount and the length of the hydride in the midwall area of the cladding depended on the temperature and the cooling rate from the HRT due to hydrogen migration from the hydride rim area. It is deduced that the ductility in ring compression deformation was affected by the orientation, amount, and length of hydride in the midwall area.
Comparison of the Temperature and Pre-Aging Influences on the Low Cycle Fatigue and Thermo-Mechanical Fatigue Behavior of Copper Alloys (CuCoBe/CuCo2Be)
Authors: Koeberl H. , Winter G. , Leitner H. , Eichlseder W.
Published: January 2009

Typically thermo-mechanical fatigue (TMF) loaded components in power plants and steel works are made of copper alloys and are used in different applications (e.g. cooling systems in continuous casting, transformers). So a careful analysis and comparison of the experimental results and microstructure of thermo-mechanical loaded copper components, which are based on a systematic variation of the relevant influence factors, have been conducted to develop empirical models for computing the fatigue life. At specific low cycle fatigue (LCF) and thermo-mechanical fatigue test series on the copper alloys CuCoBe and CuCo2Be, the influence of pre-aging and temperature were investigated by means of the cyclic deformation and lifetime behavior. Based on stress-strain loops from LCF tests at different temperatures and aging conditions a non-linear combined material model was adopted to describe the cyclic deformation behavior. The simulated loading parameters of stress and strain were the basis for the subsequent lifetime simulation. A new energy based damage parameter for copper alloys has been developed to fulfill the requirements of lifetime simulation.
Influence of the Peening Intensity on the Fatigue Behavior of Shot Peened Titanium Components
Authors: Leitner H. , Oberwinkler B. , Gaenser H.-P. , Stoschka M.
Published: January 2009

Although mechanical surface treatments are commonly used in engineering practice for their beneficial effect on fatigue life, little quantitative data are available from published literature. This paper presents the first results of a long-term research program that aims to develop quantitative design guidelines for the influence of mechanical surface treatments on the fatigue life of structural lightweight components. To gain a detailed understanding of the effects of mechanical surface treatments on surface roughness, residual stress distribution, and resulting fatigue strength, extensive experimental work as well as accompanying fracture analyses have been performed. Four-point rotating bending tests and alternating torsional tests were performed on a Ti-6Al-4V titanium alloy. Both smooth and notched specimen geometries were investigated. The heat-treated and machined specimens were subjected to a shot peening process with varying shot intensities within the recommendations of the MIL-S-13165C and MIL-P-81985 specifications. It was observed that shot peening can result in both an improvement as well as a deterioration in fatigue strength, depending on the shot peening intensity and the type of loading. For the assessment of the fatigue failure mechanisms, detailed investigations of the surface layer were included in the research program.
Effects of Contamination on Aerospace Hydraulic Component and System Performance
Authors: Snyder Carl Ed , Gschwender Lois J. , Sharma Shashi K.
Published: January 2009

Most papers concerning hydraulic systems contamination cover primarily the adverse effects of particulate contamination on hydraulic component and system performance. While that is a valid concern, the effects of other contaminants can also be serious. This paper concentrates on the adverse effects of water, free air, and chemical contaminants on military aerospace hydraulic component and systems performance. The hydraulic fluids used in the military aerospace systems are both the mineral oil-based MIL-PRF-5606 [1] and the synthetic hydrocarbon-based fire resistant hydraulic fluids MIL-PRF-83282 [2], and MIL-PRF-87257 [3]. Examples will be provided where each of the contaminants were responsible for some adverse effect and the recommended solution for the problems will be provided. Some of the problems encountered were stuck valves, spongy controls, “burnt” hydraulic fluid, and erratic actuator performance. The methodology used to identify the source of the problem will be presented. Based on the problems found, limits for these contaminants were recommended and, when followed, solved the problems for the aircraft involved. The major significance of this paper is to enlighten the aerospace hydraulic system community to the potential problems caused by contamination other than particulate contamination and to suggest solutions for these problems.
Study of Weatherability of Construction Sealants with Novel Testing Method
Authors: Enomoto Noriyoshi , Ito Akihiko , Shimizu Ichirou , Matsumura Takashi , Takane Yoshimitsu , Tanaka Kyoji
Published: January 2009

Although construction sealants are used for all kinds of construction joints such as static joints with little movement, dynamic joints with thermal or seismically induced movement, and so on, the general test methods employed in the evaluation of the weatherability of construction joint are based on weathering test without movement. In November of 2000, AIJ (Architectural Institute of Japan) established a subcommittee chartered with developing an accelerated weathering test method, which enables the determination of the durability of waterproofing materials and sealants. In this activity, we evaluated the weatherability of sealants with a new test method using newly developed test specimens, which enable exposing the cured sealants to compression and extension at the same time in a single test specimen. In this paper, we report the interim test results, which cover twelve months of natural weathering and 3500 hours artificial weathering with xenon lamp and carbon flame weathering device. In this evaluation, we confirm that the surface degradation of sealants is accelerated by the additional movement cycles, and the differences in the degradation among the sealants are becoming observable.
Proposed Design and Method for Providing Sealed Joint Performance under Relative Story Displacement
Authors: Miyauchi Hiroyuki , Tanaka Kyoji
Published: January 2009

The fatigue resistance of sealed joints to relative story displacement movements caused by earthquakes was studied experimentally and analytically, and the new joint design method was proposed, providing adequate sealed joint performance over the joint’s service life. First, the story drift R of a curtain wall panel and the number of movement cycles of relative story displacement at a sealed joint over its service life were investigated using earthquake data of the Japan Meteorological Agency. The results indicate that the number of cyclic movements at a sealed joint over its service life is inversely proportional to the story drift of the adjacent curtain wall panels. In regions where earthquakes are numerous, R=1/300 cyclic movements of the total length of the curtain wall panel occur several thousand times over a period of 75 years, while R=1/100 cyclic movements occur only several tens of times. Second, the three criteria required to create a joint design method were investigated, i.e., type of sealant, effect of cross-sectional size and shape of the sealed joint, and fatigue resistance of the sealant at intersectional zones of sealed joints to the sliding and rocking motions of curtain wall panels. It was obvious that the fatigue resistance of sealed joints was lower in the intersectional area than in the linear sections of the joints, and was lowest in the event of the same movement occurring in both vertical and horizontal joints. The fatigue resistance of a sealant at the intersection of sealed joints is not sufficient to attain the targeted service life and the fatigue resistance of this area of the sealed joint must be improved by applying larger curvature radii at the corner of the curtain wall panel. Finally, the new joint design process for the linear section and the intersection of the sealed joints to relative story displacement movements was developed based on the experimental data. Further, we proposed the methodology to estimate the expected service life of a sealed joint.
Olfactory Sensitivity of Pacific Lampreys to Lamprey Bile Acids
Authors: Robinson T. Craig , Sorensen Peter W. , Bayer Jennifer M. , Seelye James G.
Published: January 2009

Pacific lampreysLampetra tridentataare in decline throughout much of their historical range in the Columbia River basin. In support of restoration efforts, we tested whether larval and adult lamprey bile acids serve as migratory and spawning pheromones in adult Pacific lampreys, as they do in sea lampreysPetromyzon marinus. The olfactory sensitivity of adult Pacific lampreys to lamprey bile acids was measured by electro‐olfactogram recording from the time of their capture in the spring until their spawning in June of the following year. As controls, we tested L‐arginine and a non‐lamprey bile acid, taurolithocholic acid 3‐sulfate (TLS). Migrating adult Pacific lampreys were highly sensitive to petromyzonol sulfate (a component of the sea lamprey migratory pheromone) and 3‐keto petromyzonol sulfate (a component of the sea lamprey sex pheromone) when first captured. This sensitivity persisted throughout their long migratory and overwinter holding period before declining to nearly unmeasurable levels by the time of spawning. The absolute magnitudes of adult Pacific lamprey responses to lamprey bile acids were smaller than those of the sea lamprey, and unlike the sea lamprey, the Pacific lamprey did not appear to detect TLS. No sexual dimorphism was noted in olfactory sensitivity. Thus, Pacific lampreys are broadly similar to sea lampreys in showing sensitivity to the major lamprey bile acids but apparently differ in having a longer period of sensitivity to those acids. The potential utility of bile acid‐like pheromones in the restoration of Pacific lampreys warrants their further investigation in this species.
VISUAL REINFORCEMENT IN THE FEMALE SIAMESE FIGHTING FISH, BETTA SPLENDENS
Authors: Elcoro Mirari , Silva Stephanie P. da , Lattal Kennon A.
Published: February 2009

Operant conditioning with Betta splendens (Bettas) has been investigated extensively using males of the species. Etiological studies of female Bettas have revealed aggressive interactions that qualitatively parallel those between male Bettas. Given these similarities, four experiments were conducted with female Bettas to examine the generality of a widely reported finding with males: mirror‐image reinforcement. Swimming through a ring was reinforced by a 10‐s mirror presentation. As with males, ring swimming was acquired and maintained when mirror presentations were immediate (Experiments 1, 2, and 3) and delayed (Experiment 4). The failure of conventional extinction (Experiments 1 and 2) and response‐independent mirror presentations (Experiment 3) to maintain responding confirmed the reinforcing properties of mirror presentation. These results extend previous findings of mirror images as reinforcers in males of the same species and illustrate a complementarity between behavioral ecology and the experimental analysis of behavior.
Integrated Ganges basin management: conflict and hope for regional development
Authors: Rahaman Muhammad Mizanur
Published: February 2009

The aim of this research is to highlight the various factors relating to the water conflict among the riparian countries in the Ganges basin and to examine the potential benefits of integrated water development. Lack of cooperation between the nations involved who promote a nationalistic approach for the management of the basin have made integrated development difficult. This paper examines the issues related to the utilization of the Ganges water resources, regional water-based development potentials and views of riparian countries on integrated Ganges basin management. It identifies four types of prospective benefit from integrated Ganges basin management: benefits to the river; benefits from the river; reducing costs because of the river; and benefits beyond the river. Finally, it recommends guidelines to overcome the constraints to integrated Ganges management and, hence, achieve overall regional development. This paper stresses the need to develop an integrated water management approach intended to foster regional development and overcome the prospect of severe water conflict along the Ganges basin.
Evaluation of biodegradation potential of organic compounds by river water microorganisms
Authors: Inoue D. , Inaba M. , Yu N. , Shima Y. , Ueno T. , Sei K. , Fujita M. , Ike M.
Published: January 2009

The aim of this study was to assess the availability of the biodegradation potential of aniline and phenol as the indicator for evaluating pollutant impact on a river environment. Biodegradation tests employing river water microorganisms were carried out by a modified TOC-Handai method using aniline and phenol as substrates. Complete degradation time and half-life were determined as indicators expressing the biodegradation potential of aniline and phenol, respectively. Investigations in Lake Biwa-Yodo River basin for more than two years showed that the biodegradation potential of both compounds varied seasonally. In addition, aniline biodegradation potential seemed to be influenced by the hydraulic retention time at each sampling station, while downstream stations with large input of wastewater from the surrounding cities were divided from upstream stations by phenol biodegradation potential. Comparison of the biodegradation potential in rivers at different pollution levels also showed that polluted and less polluted rivers were clearly divided by phenol biodegradation potential. These results indicated that phenol biodegradation potential can be applied as an indicator for evaluating the soundness of river environment from the view point of ecological function.
Pollutant removal within hybrid constructed wetland systems in tropical regions
Authors: Yeh T. Y. , Wu C. H.
Published: January 2009

Hybrid constructed wetlands have received tremendous interests for water quality enhancement due to insufficient sewage treatment and groundwater deterioration in Taiwan. The main objectives of this study were to investigate pollutant removal efficiencies and mechanisms within field-scale hybrid natural purification systems. The studied hybrid constructed wetland systems include an oxidation pond, two serial surface flow wetlands with a cascade in between, and a subsurface flow wetland receiving secondary treated dormitory sewage. The average SS, BOD and COD percent removal efficiency was 86.7, 86.5 and 57.8%, respectively. The ratio of BOD to COD decreased from 0.65 in the initial aerobic compartment to 0.21 in anoxic parts of the systems, indicating most biological degradable materials were decomposed in the aerobic oxidation pond and surface flow wetlands. Heavy metal removal percentages of copper and zinc were 72.9 and 68.3%, respectively. Sedimentation and plant uptake are the possible sinks for metals retention. Significant phosphorus removal was not achieved in this study. Total Kjeldahl nitrogen (TKN) and ammonium decreased from 4.08 to 1.43 and 3.74 to 1.21 mg/L, respectively, while nitrate nitrogen increased from 1.91 to 3.85 mg/L within the aerobic oxidation pond and surface flow wetlands. This result demonstrated nitrification occurring within aerobic compartments. The nitrate nitrogen continued to decrease from 3.85 to 1.43 mg/L within the anoxic subsurface wetlands mainly through denitrification transformation. Total nitrogen removal was from 7.61 to 3.61 mg/L, with the percentage removal of total nitrogen around 52.6%. The primary nitrogen removal and transformation mechanisms within the studied wetland systems were nitrification within aerobic followed by denitrificaiton within anaerobic systems. The emergent macrophytes enhance aeration through oxygen transferring that attributing the higher organic matter removal and nitrification rate. The hybrid wetland systems are viable options of pollutants transformation and removal in tropical countries, while tertiary wastewater systems are too costly or unable to operate. Effluent of purified systems can comply with local surface water criteria rendering for groundwater recharge.
Using treated wastewater to save wetlands impacted by climate change and pumping
Authors: McFarlane D. J. , Smith A. , Bekele E. , Simpson J. , Tapsuwan S.
Published: January 2009

Wetlands occur where the watertable which underlies much of Perth intersects the land surface. Regional groundwater levels have been falling since the 1970s as a result of lower rainfall and increased extraction causing a loss of environmental and social values. This paper examines a scheme to add almost 2 GL/yr of treated wastewater to infiltration galleries immediately down-gradient of Perry Lakes so that the wetlands may be restored. Modelling suggest that groundwater levels would be raised up-gradient of the galleries, increasing both lake levels and groundwater supplies in the vicinity. It is not envisaged that wastewater will enter the lakes. Adding treated wastewater to nearby trial galleries has shown that phosphorus, pathogens and organic carbon are greatly reduced within 5 to 50 m. Nitrogen levels are less reduced but are similar to those in the lakes and nearby aquifer. It is estimated that the wetlands add about $54 m to land prices near the lakes and would add more than $24M to the sale price of proposed nearby land if they contain water. If successful, the proposal could be a test case for the use of treated wastewater to create hydraulic barriers against salt water intrusion into coastal areas.
Infrastructure optimisation via MBR retrofit: a design guide
Authors: Bagg W. K.
Published: January 2009

Wastewater management is continually evolving with the development and implementation of new, more efficient technologies. One of these is the Membrane Bioreactor (MBR). Although a relatively new technology in Australia, MBR wastewater treatment has been widely used elsewhere for over 20 years, with thousands of MBRs now in operation worldwide. Over the past 5 years, MBR technology has been enthusiastically embraced in Australia as a potential treatment upgrade option, and via retrofit typically offers two major benefits: (1) more capacity using mostly existing facilities, and (2) very high quality treated effluent. However, infrastructure optimisation via MBR retrofit is not a simple or low-cost solution and there are many factors which should be carefully evaluated before deciding on this method of plant upgrade. The paper reviews a range of design parameters which should be carefully evaluated when considering an MBR retrofit solution. Several actual and conceptual case studies are considered to demonstrate both advantages and disadvantages. Whilst optimising existing facilities and production of high quality water for reuse are powerful drivers, it is suggested that MBRs are perhaps not always the most sustainable Whole-of-Life solution for a wastewater treatment plant upgrade, especially by way of a retrofit.
Biosolids odor reduction by solids inventory management in the secondary activated sludge treatment system
Authors: Sekyiamah K. , Kim H.
Published: January 2009

A wastewater treatment plant consists of unit processes designed to achieve specific waste reduction goals. Offensive odors associated with these treatment processes are a constant source of public complaints. The purpose of this study was to statistically determine the process parameters that influence the formation of volatile sulfur compounds (VSCs) in the secondary treatment system. A statistical model was developed to relate the process parameters to the formation of VSCs in this system. The model established that F/M ratio, sludge blanket depth and SSV60 were the dominant process parameters that influenced the formation of VSCs in the secondary sedimentation basin. This model provides a useful tool for plant engineers to predict and control the VSC formation in a secondary activated sludge treatment system.
Comparative assessment of gene quantification using real-time PCR and water quality parameters in unsanitary landfill
Authors: Han J. S. , Kim C. G.
Published: January 2009

Because of increasing demanding for development of direct ecological landfill monitoring methods, there is a requirement for the condition of landfills and their influence on the environment to be characterized by the behavior of enzymes and bacteria mainly concerned with biochemical reaction in the landfills. This study was thus conducted to understand the fates of contaminants in association with groundwater quality parameters. For the study, groundwater was seasonally sampled from four closed unsanitary landfills in which microbial diversity was simultaneously obtained by 16S rDNA methods. Subsequently, a number of the specific genes of representative bacteria and encoding enzymes were quantified by real-time PCR. The relationship between water quality parameters and gene quantification were compared based on correlation factors. Correlation between DSR gene and BOD was greater than 0.8 while NSR gene and nitrate were related more than 0.9. For MTOT, it was at the highest related at 100% over BOD/COD and Dde genes were correlated over 0.8. In addition, anaerobic genes and DO were also related more than 0.8, showing anaerobic reactions generally dependent upon DO. As demonstrated in the study, molecular biological investigation and water quality parameters are highly co-linked, so that quantitative real-time PCR could be cooperatively used for assessing landfill stabilization in association with the conventional monitoring parameters.
A novel laboratory cultivation method to examine antibiotic-resistance-related microbial risks in urban water environments
Authors: Oh H. , Lee J. , Kim K. , Kim J. , Choung Y. , Park J.
Published: January 2009

Although microbial risk due to antibiotic-resistant microbes in water has been a serious public health concern, the current culture-dependent detecting methods using nutrient-rich conditions may not be suitable for evaluating microbial risk. In the present study, a novel cultivation method was developed to detect antibiotic-resistant microbes at various nutrient levels. A nutrient-rich medium Luria-Bertani broth (LB) was diluted at a wide range of dilution factors (100−104) and amended with either tetracycline or vancomycin. A standard environmental cultivation medium, R2A, was also used by amending with antibiotics. The diluted LB with antibiotics was able to detect previously known oligotrophic and antibiotic-resistant bacteria in drinking water and swine manure samples, respectively. These results validate the capability of the new method to detect antibiotic-resistant microbes in various environmental water samples. Using the developed method in assessing microbial risk due to antibiotic-resistant microbes in river and municipal wastewater plants, we found that the viable counts and antibiotic resistance fraction were significantly influenced by the type and concentration level of antibiotic exposure and the cultivation medium conditions. This suggests a further need to standardize cultivation method procedures, to assess microbial risk in water samples.
Using reclaimed water as make-up water for a district heating system: a case study in Beijing
Authors: Yajun Zhang , Huizhen Wang , Ping Xu , Cuimin Feng
Published: January 2009

Make-up water used for a district heating system in Beijing is about 63 kg/m2.a, so the total quantity of make-up water is over 10 million m3 per year. Water deficiency is very serious in Beijing. Using reclaimed water as make-up water is one of the important measures to relieve water crises of the city. This study is mainly on nanofiltration (NF) process. The reclaimed water for the experiment is the effluent of The Sixth Water Plant, an urban reclaimed water plant in Beijing. Micro-filter (MF) and activated carbon filtration are used as pretreatment units to eliminate turbidity, organic matter in reclaimed water to avoid contamination and scale on the surface of NF membrane. Four SAEHAN NE-90 membrane elements with an array of 2-1-1 are selected for the NF unit and the flow rate is controlled around 1 m3/h. Through the test, it has been verified that NF membrane has high removal rate to the salt and impurity of reclaimed water. The average salt removal rate of the system is more than 94%, while the rejections of bivalent ions are more than 98%. The removal rates of organic matter, NH3-N and TP are 77%, 96% and 84% respectively. Temperature is a main influence of the process. When temperature is increasing, the permeate flux is increasing as well. The operating pressure is an important factor effecting membrane flux also. By the data comparison it is confirmed that the appropriate operating pressure and the water recovery of NF system are 0.75 MPa and 63.5% respectively.
Recovery of heavy metals from industrial sludge using various acid extraction approaches
Authors: Wu C. H. , Kuo C. Y. , Lo S. L.
Published: January 2009

Heavy metals were removed from industrial sludge by traditional and microwave-assisted acid extraction approaches. The effects of acid concentration, extraction time, sludge particle size and solid/liquid (S/L) ratio on copper-extraction efficiency were assessed. Leaching with increased acid concentrations increased the yield of heavy metals from the industrial sludge. In microwave-assisted acid extraction, reducing the S/L ratio and sludge particle size increased copper-extraction efficiency. These experimental findings indicate that S/L ratio most strongly influenced microwave-assisted acid extraction. Both traditional and microwave-assisted acid extraction demonstrate that sulfuric acid was an effective extractant, and the copper fraction in extracted sludge shifted from being primarily bound to Fe–Mn oxides and organic-matter partition, to being mostly bound to organic matter, remaining as a residue during acid extraction.
Variability analysis of pathogen and indicator loads from urban sewer systems along a river
Authors: Åström J. , Pettersson T. J. R. , Stenström T. A. , Bergstedt O.
Published: January 2009

The pathogen loads within surface waters originating from urban wastewater sources needs to be assessed to support drinking water risk estimations and optimal selection of risk reduction measures. Locally reported discharges from sewer systems (>100,000 persons connected) were used to simulate the potential microbial loads into the Göta älv river, Sweden. Using Monte Carlo simulations, the median and 95% percentile (i.e. worst case) of total microbial load from wastewater treatment plants, sewer network overflows and emergency discharges were assessed and presented for dry and wet weather conditions. Wastewater treatment plants with secondary treatment represented a major source of E. coli, norovirus, Giardia and Cryptosporidium. During wet weather, comparably high microbial loads were found for sewer overflows due to heavy rains. Substantial loads were also associated with an incident of the emergency discharge of untreated wastewater. Simulated river water concentrations of faecal indicators (E. coli, sulfite reducing clostridia, somatic coliphages) and pathogens (norovirus, Giardia, Cryptosporidium) were confirmed by river sampling data, suggesting that urban wastewater is the major microbial source for this river.
Biodegradation of phenol by aerobic granulation technology
Authors: Khan Farah , Zain Khan Mohammad , Qamar Usmani Shams , Sabir Suhail
Published: January 2009

High organic load and fluctuation in organic load in terms of total phenols is fed into a SBR of higher height and diameter ratio (H/D 20) and operated at 4 h cycle basis with a volumetric exchange ratio of 50% resulting in a constant HRT of 8 h. Successful cultivation of aerobic granules was achieved. Aerobic granulation technology system withstands the inhibitory effect as well as fluctuation of organic load and a better efficiency as compared to traditional activated sludge process. Maximum phenol concentration of 650 mg l−1 is treated efficiently in 4 h which is equal to an organic load of 3.9 kg m−3 d−1. After granulation the effluent phenol and COD concentrations were 3 mg l−1 and 41 mg l−1 respectively. Phenol removal efficiency and COD removal efficiency of 94% and 95% were achieved. Effluent O.D.600 stabilizes at 0.15 which corresponds to minimum loss of biomass, which is the main advantage of SBR.
Competitive adsorption of heavy metals in soil underlying an infiltration facility installed in an urban area
Authors: Hossain M. A. , Furumai H. , Nakajima F.
Published: January 2009

Accumulation of heavy metals at elevated concentration and potential of considerable amount of the accumulated heavy metals to reach the soil system was observed from earlier studies in soakaways sediments within an infiltration facility in Tokyo, Japan. In order to understand the competitive adsorption behaviour of heavy metals Zn, Ni and Cu in soil, competitive batch adsorption experiments were carried out using single metal and binary metal combinations on soil samples representative of underlying soil and surface soil at the site. Speciation analysis of the adsorbed metals was carried out through BCR sequential extraction method. Among the metals, Cu was not affected by competition while Zn and Ni were affected by competition of coexisting metals. The parameters of fitted ‘Freundlich’ and ‘Langmuir’ isotherms indicated more intense competition in underlying soil compared to surface soil for adsorption of Zn and Ni. The speciation of adsorbed metals revealed less selectivity of Zn and Ni to soil organic matter, while dominance of organic bound fraction was observed for Cu, especially in organic rich surface soil. Compared to underlying soil, the surface soil is expected to provide greater adsorption to heavy metals as well as provide greater stability to adsorbed metals, especially for Cu.