Microbial induced acid corrosion from a field perspective - Advances in process understanding and construction material development

Microbial induced acid corrosion is accounted for ~40 % of the degradation of subsurface wastewater infrastructure globally. While fundamental process understanding has increased significantly within the last decades, to date no sustainable building material exists, which meets the long-term requirements in such aggressive and corrosive environments. This work describes a novel model based on field studies, conducted in various Austrian sewer networks, intertwining biological, mineralogical and hydro-chemical factors. Additionally, an extensive field testing campaign over the duration of 18 months, conducted on different geopolymer concretes (GPC), particularly designed for the latter environments will be presented. Innovative GPCs were tested regarding their microstructural behavior, microbial accessibility and hydro-chemical alterations over time and compared to commercially produced cement based products, including OPC and CAC concretes. Additionally, the system specific environmental parameters, such as relevant gas concentrations (H2S, CO2, CH4), relative humidity and temperature were constantly monitored.

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Mineralogical Composition and Physical–Mechanical Properties of Dasht-E-Taatrang Zar Sand Deposits (Afghanistan)

Environmental Sciences Proceedings ◽

10.3390/iecg2020-08832 ◽

2020 ◽

Vol 5 (1) ◽

pp. 2

Author(s):

Hemayatullah Ahmadi ◽

Atal Yousufi ◽

Amir Mohammad Mosazai

Keyword(s):

Mechanical Properties ◽

Construction Material ◽

Mineralogical Composition ◽

Xrd Analysis ◽

Sample Collection ◽

Extensive Field ◽

Chemical And Mineralogical Composition ◽

New City ◽

Two Phases ◽

Field Works

Sand is a common construction material used for various purposes, e.g., concrete, mortar, render, screed, and asphalt. The usage depends on its fineness, and its fineness is controlled by its mineralogical composition and physical-mechanical properties. This research aims to determine the chemical and mineralogical composition and the physical-mechanical properties of the Dasht-e-Taatrang Zar sand deposits within the Qarabagh and Bagram districts of Kabul and Parwan provinces in Afghanistan. To achieve the objectives of this research, a review of the existing literature has been combined with new extensive field works for macroscopic studies and sample collection, and laboratory analyses. In total, 23 samples during two phases of field works were collected and subjected to lab works for XRF, Schlich, and XRD analysis to determine the chemical and mineralogical composition; moreover, sieve and Atterberg analysis, specific gravity, soundness, and alkali-silica reaction tests were performed for characterization of the physical-mechanical properties of the studied samples. The results of the tests show that the Taatrang Zar sand deposits are considered as a suitable construction material, and due to their simple accessibility, the deposits have high potential as a construction material supplier for the Kabul new city project (Dehsabz) in Kabul and adjacent Parwan and Kapisa provinces.

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A Diagnosis of Urban Poor Housing in Vietnam

Open House International ◽

10.1108/ohi-02-2017-b0014 ◽

2017 ◽

Vol 42 (2) ◽

pp. 97-105

Author(s):

Iftekhar Ahmed

Keyword(s):

Affordable Housing ◽

Urban Poor ◽

Field Studies ◽

Economic Reforms ◽

Cultural Dimensions ◽

Ho Chi Minh City ◽

Housing Sector ◽

Housing Supply ◽

Extensive Field ◽

Key Factor

This paper presents concepts important for understanding urban poor housing in Vietnam, with a focus on key environmental, socio-economic, and cultural dimensions that bear on the housing sector. The paper draws on extensive field studies and presents a diagnosis of the context of and prospects for housing of the urban poor in Vietnam's two main cities: Hanoi and Ho Chi Minh City. While the literature on this theme is scanty, it points to the market-orientated economic reforms initiated in the 1980s as a key factor in creating imbalance in the housing supply. Recognising the current challenges in balancing affordability and sustainability, the study explores Vietnam's lack of adequate and affordable housing and the problems faced by the urban poor in accessing adequate housing.

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DEVELOPING INSTRUCTIONAL MATERIALS OF ENGLISH MORPHOLOGY FOR ENGLISH DEPARTMENT COLLEGE-LEARNERS

Journal on English as a Foreign Language ◽

10.23971/jefl.v5i1.94 ◽

2015 ◽

Vol 5 (1) ◽

pp. 1

Author(s):

Chothibul Umam

Keyword(s):

English Language ◽

Language Education ◽

Field Testing ◽

Instructional Materials ◽

Word Choice ◽

Course Content ◽

Instructional Process ◽

Material Development ◽

State College ◽

Materials Used

The role of knowledge on English Morphology for the students of English Language Education (henceforth ELE) cannot be neglected. However, the preliminary observations done by the researcher during the instructional process of English Morphology at the State College for Islamic Studies (STAIN) Kediri Indonesia, for three academic years shows that most of the students still get difficulty in understanding the course content. The researcher, therefore, is of the opinion that the instructional materials used in the classes need to be developed. The adaptation version of Borg & Gall (1983) model of R & D covering preliminary observation, designing preliminary product, expert validation, product revision, field testing or try out, and revision to produce final product is used to develop an instructional material on English Morphology. The products mostly concern on 1) the course content, 2) the exercises, and 3) the level of language difficulty or word choice. The researcher expects that the final product of this study could be used as a handbook for the students in studying English Morphology.Keywords: instructional materials, material development, English morphology

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Material Development in Production Ecrite Intermediaire by Sipda to Improve the Writing Ability the Student of French Departement at Faculty of Languages and Arts at One of State Universities in Northen Island of Indonesia

Britain International of Linguistics Arts and Education (BIoLAE) Journal ◽

10.33258/biolae.v3i2.464 ◽

2021 ◽

Vol 3 (2) ◽

pp. 135-142

Author(s):

Tengku Ratna Soraya ◽

Zulherman ◽

Nurilam Harianja ◽

Hesti Fibriasari

Keyword(s):

Teaching And Learning ◽

Language Education ◽

Field Testing ◽

French Language ◽

State Universities ◽

Teaching Materials ◽

Study Program ◽

Writing Ability ◽

Material Development ◽

Education Study

This study aims to develop teaching materials in Production Ecrite Intermediare course to improve the writing ability the student of french departement at Faculty of Languages and Arts at One of State Universities in Northen Island of Indonesia by using SIPDA. This research was conducted to response the condition of covid pandemic situation that uses distance learning courses where students learn from their own homes. This research followed the R & D model proposed by Borg & Gall with the procedure analysing the student’s need, collecting the ressource of development, design the material, evaluatingexisting the materials based on the validation of experts judgement, field testing, revising, and finishing the final product. This research was carried out in the French Language Education Study Program FBS UNIMED by developing SIPDA-based teaching materials in lectures, to find out that these teaching materials can improve the writing skills of students of French Language Education Study Program at FBS Unimed. The results of this study show that SIPDA is very effective in helping students to improve the writing ability of French texts. This research recommends to the lecturers of French courses in general to using SIPDA in the teaching and learning process of writing in the classroom of Production Ecrite Intermediaire.

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Rape and the Prevalence of Hybrids in Broadly Sympatric Species: a Case Study using Albatrosses

10.7287/peerj.preprints.384 ◽

2014 ◽

Cited By ~ 1

Author(s):

Sievert Rohwer ◽

Rebecca B. Harris ◽

Hollie E. Walsh

Keyword(s):

Species Differences ◽

Field Studies ◽

Sympatric Species ◽

Male Reproductive Success ◽

Gene Exchange ◽

Nuclear Markers ◽

Mitochondrial Markers ◽

Extensive Field

Conspecific rape often increases male reproductive success. However, the haste and aggression of forced copulations suggests that males may sometimes rape heterospecific females, thus making rape a likely, but undocumented, source of hybrids between broadly sympatric species. We present evidence that heterospecific rape may be the source of hybrids between Black-footed and Laysan Albatrosses (Phoebastria nigripes, and P. immutabilis, respectively). Extensive field studies have shown that paired (but not unpaired) males of both of these albatross species use rape as a supplemental reproductive strategy. Between species differences in size, timing of laying, and aggressiveness suggest that Black-footed Albatrosses should be more successful than Laysan Albatrosses in heteropspecific rape attempts, and male Black-footed Albatrosses have been observed attempting to force copulations on female Laysan Albatrosses. Nuclear markers showed that the six hybrids we studied were F1s and mitochondrial markers showed that male Black-footed Albatrosses sired all six hybrids. The siring asymmetry found in our hybrids may have long persisted because an IM analysis suggests that long-term gene exchange between these species has been from Black-footed Albatrosses into Laysan Albatrosses. If hybrids are sired in heterospecific rapes, they presumably would be raised and sexually imprinted on Laysan Albatrosses, and two unmated hybrids in a previous study courted only Laysan Albatrosses.

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Experience with Field Testings of SHE on Research Catchments

Hydrology Research ◽

10.2166/nh.1984.0025 ◽

1984 ◽

Vol 15 (4-5) ◽

pp. 283-294 ◽

Cited By ~ 7

Author(s):

Børge Storm ◽

K. Høgh Jensen

Keyword(s):

New Zealand ◽

Soil Water ◽

Flow Model ◽

Complete System ◽

Field Testing ◽

Practical Applications ◽

Extensive Field ◽

Soil Water Flow ◽

Hydrologic System ◽

The Individual

The development of the European Hydrologic System (SHE) has now reached such a stage, that it is ready for practical applications. Extensive field testings and associated developments have been carried out in recent years. The testings have included the complete system as well as the individual components. Particular emphasis has been given to the development and testing of the soil water flow model. The paper demonstrates results from a field testing of SHE on the Wye Catchment in Britain, as well as examples of applications on small experimental catchments in Germany and New Zealand.

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Curvilinear Behavior of Base Layer Moduli from Deflection and Seismic Methods

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1716-07 ◽

2000 ◽

Vol 1716 (1) ◽

pp. 55-63

Author(s):

Kamal Tawfiq ◽

John Sobanjo ◽

Jamshid Armaghani

Keyword(s):

Surface Deformation ◽

Low Frequency ◽

Field Testing ◽

Base Layer ◽

Falling Weight Deflectometer ◽

Seismic Methods ◽

Extensive Field ◽

Curvilinear Relationships ◽

Falling Weight ◽

Surface Deflections

The reality of curvilinear relationships of stiffness versus deformation is usually neglected when moduli values from seismic methods are compared with those of deflection methods. On the basis of extensive field testing, results showed that moduli values for the base layers from deflection methods did not conform to those of seismic methods. Deflection testing techniques were signified by the falling weight deflectometer (FWD) and the Dynaflect methods. Seismic testing was carried out by use of the seismic pavement analyzer (SPA) method. The SPA test results yielded moduli values higher than those obtained from the deflection methods. Utilizing pavement parameters obtained from the SPA data, researchers determined surface deflections by use of frequency response functions of signals from the two groups of sensors used in the testing setup. Because of the types of hammers in the SPA testing, two different deflection basins were obtained at each testing point. Comparison of surface deflections from these methods indicated that deflection amplitudes from the FWD method were about 100 times higher than those obtained from the high-frequency hammer of the SPA. At certain pavement sections, deflections from the Dynaflect method were comparable to those obtained with the SPA low-frequency hammer. Accordingly, curvilinear relationships between surface deformation versus stiffness values were derived. These relationships can be used to determine moduli values at all surface deflections, including those from service loads.

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Model research on the influence of green roofs on environmental parameters in urban agglomerations

E3S Web of Conferences ◽

10.1051/e3sconf/20184500094 ◽

2018 ◽

Vol 45 ◽

pp. 00094 ◽

Cited By ~ 3

Author(s):

Dariusz Suszanowicz

Keyword(s):

Heavy Metals ◽

Urban Areas ◽

Air Pollutants ◽

Green Roof ◽

Soil Layer ◽

Environmental Parameters ◽

Green Roofs ◽

Field Studies ◽

Air Pollutant ◽

Laboratory Scale

This study presents features of green roofs in urban areas with a particular emphasis on the filtration of air pollutants, heavy metals removal, reduction of rainwater runoff from roof surfaces and thermal insulation. To carry out field studies on the influence of green roofs on the environment in urban areas, two green roof models on a laboratory scale were used. The observations of the prepared green roof models made during the summer, autumn and winter confirmed the extremely beneficial effect of this type of roof for the elimination of air pollutant, heavy metals, and particulate matter. The observations also confirmed that plants on a green roof growing on a soil layer absorb an average of 74% of rain water and then allow it to evaporate. The selection of plants for green roofs should mainly focus on how effectively they improve urban environmental parameters and remove air pollutants. The results of the study of the two green roof models on a laboratory scale are necessary to work out the parameters of layers of the roof and select the most appropriate plants for the reference research object on the roof of one of buildings of the University of Opole.

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The use of Runoff and Surface Water Transport and Fate Models in the Pesticide Registration Process

Weed Technology ◽

10.1017/s0890037x00036149 ◽

1992 ◽

Vol 6 (3) ◽

pp. 743-748 ◽

Cited By ~ 4

Author(s):

Paul L. Zubkoff

Keyword(s):

Surface Waters ◽

Environmental Fate ◽

Transport Model ◽

Numerical Models ◽

Chemical Properties ◽

Chemical Characterization ◽

Fate And Transport ◽

Environmental Parameters ◽

Field Studies ◽

Chemical Application

In support of the registration and reregistration processes under FIFRA ‘88, numerical models are used to estimate the dissolved runoff and soil erosion loadings of pesticides to surface waters and the subsequent fate and transport of pesticides in the receiving waters. Uses for simulations include:1. Helping to determine whether additional studies on the fate and distribution of a candidate chemical in the environment and/or ecological effects may be needed when full chemical characterization is incomplete.2. Helping to more fully integrate data submissions of laboratory and field observations.3. Estimating probable fate and distribution of an agrochemical after a severe runoff event.4. Comparing alternative chemical application rates and methods for the same chemical/soil/crop/environmental combinations.5. Comparing different soil/crop/environmental combinations representing different geographical areas with the same chemical.6. Evaluating preliminary designs of proposed field studies.7. Gaining insight into the environmental fate of modern chemicals that are applied at 1 to 2% of the rates of older chemicals when sampling designs and analytical methods are not available.The Office of Pesticide Programs (OPP) commonly employs the SWRRB (45, 46) and PRZM (8, 9) models for runoff and EXAMS II (5), a fate and transport model, for surface waters. These three models are used in conjunction with appropriate databases for soils, chemical properties, and meteorological and other environmental parameters. Registrants are encouraged to clearly state assumptions, identify values for parameters by citation, report results of simulations with summary tables and graphics, and interpret their results in relation to current scientific disciplines.

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Immediate Settlements of Three Test Embankments on Champlain Clay

Canadian Geotechnical Journal ◽

10.1139/t74-008 ◽

1974 ◽

Vol 11 (1) ◽

pp. 109-141 ◽

Cited By ~ 23

Author(s):

F. A. Tavenas ◽

C. Chapeau ◽

P. La Rochelle ◽

M. Roy

Keyword(s):

Yield Criterion ◽

Full Range ◽

Field Testing ◽

The Finite Element Method ◽

Critical Height ◽

Settlement Prediction ◽

A Value ◽

Extensive Field ◽

Scale Test ◽

Local Yielding

As part of an extensive field testing program, three full scale test fills were built on a soft Champlain clay deposit in Saint-Alban, Quebec.The fills were built to the same height of 11 ft (3.3 m) but with different slopes of 1.5/1, 2.5/1, and 4/1, and with resulting factors of safety of 1.24, 1.32, and 1.52. The foundations were heavily instrumented.From the observed construction behavior it was shown that the foundations behave elastically up to a critical height equal to 6, 8, and 9 ft (1.8, 2.4, and 2.7 m), respectively, or to about 50% of the failure height of each fill. Beyond this limit, local yielding of the clay occurred.The behavior in the elastic phase could be predicted adequately on the basis of CIU tests, provided Poisson's ratio be assigned a value of 0.3 instead of the usual 0.5. To obtain an adequate settlement prediction over the full range of heights, the finite element method could be used but a modified clay model should be developed which includes a yield criterion in addition to the classical failure criterion and which allow for a certain compressibility of the clay at yielding.

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