bluuebunny/crossref_metadata_2025 huggingface dataset:
Livelihoods on the Edge without a Safety Net: the Case of Smallholder Crop Farming in North-Central Namibia
Authors: Spear Dian , Chappel Angela
Published: May 2018

Semi-arid Namibia is marginal for agricultural production. Low soil fertility combined with low and variable rainfall restrict the livelihoods of smallholder farmers who often struggle to produce enough food. Although historically communities have adopted a number of coping mechanisms, climate change threatens to further reduce agricultural production. There are many additional options available to smallholder farmers to adapt to climate change, but they are not necessarily adopting these measures despite having noticed increasing temperatures and declining rainfall. Semi-structured interviews were conducted in three villages in Onesi constituency to examine what agricultural practices smallholder crop farmers use, perception of changes in their yields, their perspective on future yields and whether they are planning on changing their agricultural practices. The results suggest that to sustain the livelihoods of rural communities in north-central Namibia support is needed from local and regional authorities, as well as traditional and religious leaders to assist with enhancing access to information, enabling information sharing on adaptation options, and increasing awareness on climate change, it’s impacts and what can be done about it. In addition to this the implementation of adaptation action also requires demonstration sites and building capacity to enable the development of self-help groups.
UPAYA MENINGKATKAN PROFESIONALISME GURU BERLANDASKAN ILMU PENDIDIKAN DALAM MENCERDASKAN KEHIDUPAN BANGSA
Authors: Arum Wahyu Sri Ambar
Published: May 2018

This article discusses the important roles of the teachers in educating people to have smart life. To enable the teachers to perform their tasks professionally, some requirements have to be fulfilled. The Indonesian government has already conducted a number of efforts to improve the teacher professionalism. However, some hindrances are still faced. Having analyzed the existing situation, the article suggests some ideas to improve the teacher professionalism.
SELF REGULATION LEARNING PADA MAHASISWA FAKULTAS ILMU PENDIDIKAN UNIVERSITAS NEGERI JAKARTA
Authors: Deasyanti Deasyanti , Rangkuti Anna Armeini
Published: May 2018

University students have to learn independently. They must have skills of how to learn: thinking ability, thinking process, and learning motivation. Those abilities in cognitive psychology are known as self-regulated learning. This research involve 128 students of Education Faculty of Jakarta State University to know about description of self-regulated learning, difference of self-regulated learning between study programs, and correlation of self-regulated learning withacademic achievement.
PENGARUH MOTIVASI BERPRESTASI DAN PERILAKU KOMUNIKASI ANTARPRIBADI TERHADAP EFEKTIVITAS KEPEMIMPINAN KEPALA SEKOLAH
Authors: Hartono Abdul Nashir
Published: May 2018

This survey is aiming to analyse the effect of achievement motivation and interpersonal communication attitude towards the effectiveness of principal leadership both individually and in batches. The result of survey indicates that the effectiveness of principal leadership is predicted to be improved; achievement motivation and interpersonal communication attitude of principals must be stimulated intensively. The stimulus is intended to create a condition where the principals have chances to gain high achievement motivation and a positive communication attitude. In order to improve achievement motivation, it is recommended that promotion to be a principal is not a termination of a carrier, to make inventory, documentation and publication of achievement values, and to give achievement motivation test to principal candidates. To create positive interpersonal communication attitude, it is necessary to give them a kind of interpersonal communication training. At the same time, school management laboratory is needed to facilitate the improvement of those independent variables simultaneously besides helping principals to overcome some problems dealing with decentralization.
Issues Related to the Developmental Research: An Identified Challenge for the Development of Indian Intellectual Capital
Authors: Chakravarty Ritu Tripathi
Published: May 2018

The development of any country depends entirely on the quality of researches done for betterment of the present prevailing systems and it has been proved that the countries who have failed in doing the Research and Development have lacked far behind in being able to stand up for the minimal basics. This research paper is a reflective paper and will make an attempt of presenting the current situation of researches in India .It is evident that there is a great paucity of researches in education .The researches done if at all are lacking in their originality and authenticity. Various challenges are discussed in this paper. The analysis was based on the content analysis and author’s experiences on   number of issues related to the difficulties in conduction of researches in education. The findings reveal that the developmental researches are not taken up seriously and therefore there is no rigour in conduction of good quality researches in education. Various suggestions were given in order to improve the selection of appropriate area for the researches and other factors that could lead towards the improvement of quality of developmental researches.
3º Encontro de Cirurgia e Traumatologia Buco-Maxilo-Facial do Sertão Paraibano (III ECTBMFSPB)
Authors: Silva Júnior Silvestre Estrela da , Rocha Julierme Ferreira , Dias Ribeiro Eduardo , Araújo Filho José Cadmo Wanderley Peregrino de
Published: May 2018

Prezados Congressistas,É com grande satisfação que o corpo discente da Liga Acadêmica de Cirurgia da Universidade Federal de Campina Grande (LAC-UFCG) realizou, durante os dias 23, 24 e 25 de maio de 2018, o 3ª Encontro de Cirurgia e Traumatologia Buco-Maxilo-Facial do Sertão Paraibano (III ECTBMFSPB).Preparamos uma grade científica na qual inserimos representantes e conferencistas dos programas de residência e pós-graduação em CTBMF da região Nordeste, com o intuito de um maior fortalecimento e divulgação da especialidade e da atualização do conhecimento científico.A programação científica contou com palestras na área da cirurgia e traumatologia buco-maxilo-facial, implantodontia e áreas afins, ministradas por palestrantes renomados, que compartilharam com os congressistas o que há de mais atual e inovador na área. Os participantes também tiveram a oportunidade de apresentar e assistir às exposições de diversos trabalhos científicos, na modalidade de painel.O evento também contou com uma programação social visando uma maior interação entre congressistas e palestrantes.Portanto, o evento foi um sucesso e esperamos a colaboração de todos para o IV ECTBMFSPB. Aproveito a oportunidade para agradecer o periódico Archieves of Health Intvestigation pela honrosa oportunidade em publicar os resumos dos trabalhos apresentados no evento. Meus sinceros agradecimentos.Aguardamos todos para desfrutar no próximo ano em nossa acolhedora e calorosa morada do sol, Patos, a Capital do Sertão Paraibano.Silvestre Estrela da Silva Júnior Presidente do III ECTBMFSPB
Study of Changes in Physical Parameters of compost and vermicompost of Eucalyptus leaf litters
Authors: Nagar Ritu , Titov Anurag , Bhati Praveesh
Published: May 2018

Vermicompost and compost of leaf litter of Eucalyptus was studied in plastic bins in duplicate sets with two different proportions (100 % and 50 %). For vermicompost experiments, epigeic earthworm species Eisenia foetida and Eudrilus eugeniae were employed at 10-10 numbers each per vermicompost bins. Cattle dung was taken as control. During the entire process physical factors viz. temperature, pH, moisture content and biomass were measured and compaired. The results were reveal that initial temperature was 35°C ± 2°C in both vermicompost and compost leaf litter and after several weeks, it was set at minimum level. In 50 % leaf litter temperature was 2-3°C higher than 100 % leaf litter. pH of both vermicompost and compost mixtures were acidic in beginning phase while set at alkaline at final stage. Vermicompost had lower pH than compost. Moisture content of leaf litter also decreased in initial phase due to generation of metabolic heat but at later phase it was increased due to decreasing of metabolic heat. More changed was seen in 100 % leaf litter followed by 50 % and then cattle dung. Biomass of leaf litter was more decreased in 100 % waste then 50 % and cattle dung.
Mechanical Properties and Microstructure of Dissimilar Friction Stir Welding of Pure Aluminum to Low Carbon Steel
Authors: Abd Elnabi Mohamed Mohamed , Osman Tarek Abd Elsadek , El Mokadem Alaa Eldeen , ElshalakanyÂ Abou Bakr
Published: May 2018

The purpose of this research is to use friction stir welding (FSW) to join dissimilar  metals, annealed low carbon steel and A1050 pure aluminum. A butt joint with a similar sheet thickness of 1.9 mm was applied. The novelties of the research are relatively using high generated heat produced by a combination of low traverse speed and high rotational speed to perform the dissimilar joints and using a tool material (K107cold work tool steel) which has not been used in FSW with tool cooling. The present work studied the effect of FSW variables such as tilt angle, tool cooling, base metal location on mechanical properties. Tensile tests were used to evaluate the mechanical properties of the dissimilar joints. The microstructure specimens were examined using a scanning electron microscope (SEM). Sound dissimilar joints were successfully produced. The maximum joint efficiency obtained in this study is 51.7% of the aluminum tensile strength. The microstructure images showed that many steel fragments were sheared off from the steel surface by the tool action and scattered in the weld nugget, a continuous intermetallic compound (IMC) layer formed at the interface, the thickness of the IMC layer at the interface decreased in the thickness direction of the weld. FeAl3 IMC phase was only observed at the interface.
Laboratory Investigation of Inorganic Fouling of Low Pressure UV Disinfection Lamps
Authors: Sheriff M. , Gehr M.
Published: May 2018

Iron(III) (mainly dosed as FeCl3) is one of the main inorganic constituents associated with the fouling of UV lamps during disinfection of wastewater. A low pressure mercury lamp UV system was operated under laboratory conditions to assess the effects of heat and UV light on fouling. Iron(III) was dosed at different concentrations and fouling was monitored by measuring the UV irradiance. The potential for ferric phosphate fouling and the effects of organics were also studied.

Results showed that fouling did not occur in recirculating systems over 12 days of observation. However, in flow-through systems, the extent and rate of fouling depended on the solution Fe concentration. Furthermore, addition of phosphorus increased the fouling rate. Bulk precipitation appeared to be significant at iron(III) dosing over 3 mg/L.

Theoretical predictions of an equilibrium model (MINEQL+) showed similar trends with measured concentrations of soluble Fe and P from batch tests. However, model predictions of temperature effects alone could not account for the observed solids deposition on the quartz sleeve. Bulk precipitation, followed by sedimentation, was considered to be the dominant mechanism at high iron (III) concentrations.
Aeration Performance of Triangular Notch Weirs at Recirculating System
Authors: Baylar Ahmet , Bagatur Tamer , Tuna Ahmet
Published: May 2018

An adequate supply of dissolved oxygen is essential for the survival of aquatic organisms. Hydraulic structures can increase dissolved oxygen levels by creating turbulent conditions, where small air bubbles are carried into the bulk of the flow. Plunging overfall jets from weirs at recirculating systems are a particular instance of this. This paper seeks triangular notch weirs having different weir angle (α) and how they affect the aeration performance. It is demonstrated that the aeration efficiency of a 90° triangular notch weir is generally better than that of the other weirs.
Determination of the D/H Ratio in Natural Waters of Syria
Authors: Harfoush A. , Allaf Abdul W. , Alibrahim M.
Published: May 2018

Natural water samples were collected from various locations in Syria and were analyzed to determine the D/H ratio, using stable isotope ratio mass spectrometry. Three types of water (a, b and c) were found. The D/H ratios were from 156.6 × 10-6 to 148.9 × 10-6, 159.9 × 10-6 to 158.1 × 10-6, and 170.7 × 10-6 to 153.4 × 10-6 for a-, b- and c-type waters, respectively. The most characterized locations were found in closed dam reservoir (c-type). It is estimated that the D/H ratio in c-type water is proportional to the mean daily evaporation rate and accumulation efficiency and is inversely proportional to the water mean depth. The electrical conductivity is found to be proportional to the D/H value for each separate location of c-type water.
A Review of the Evidence for Endocrine Disruption in Canadian Aquatic Ecosystems
Authors: McMaster Mark E.
Published: May 2018

Endocrine disrupting substances in the environment and the potential affects they have on wildlife species has recently received increased public attention. This paper provides background information on research that has addressed the endocrine disruption issue in the Canadian aquatic environment as well as information on studies that are presently being conducted within the country to address this issue. Two of the three studies from across the world often cited as presenting sufficient evidence for connecting contaminants and endocrine disruption in fish populations are Canadian — Lake Ontario lake trout and TCDD and related compounds, and white sucker exposed to bleached kraft pulp mill effluent. Several other Canadian examples exist, including altered stress responses in yellow perch exposed to heavy metals, altered smoltification in Atlantic salmon exposed to 4-nonylphenol and imposex in dogwelks exposed to tributyltin. While other Canadian studies suggest alterations in reproductive function in fish, direct links to contaminants have not been made. Other studies have identified endocrine active compounds in the receiving environments but have yet to link these to alterations in endocrine function in resident fish populations. The strength of Canada's research programs lies in the breadth and depth of their field related research. It is this world-recognized expertise and strength that Canada can contribute to the international effort to address the endocrine disruptor issue.
Effects of Endocrine Disrupting Chemicals on Wildlife in Canada: Past, Present and Future
Authors: Fox Glen A.
Published: May 2018

Within a few years of their widespread introduction into the environment, there were major concerns about the effects of man-made chemicals on wildlife in Canada. Biologists have found evidence of endocrine disruption in at least 16 species of birds (particularly fish-eating and predatory species), 3 species of terrestrial mammals and 1 whale, 1 reptile and several amphibians. These effects were seen in the Great Lakes, areas polluted with pulp and paper effluents, the forests of New Brunswick, a variety of agricultural habitats, acidified lakes in Nova Scotia, major rivers and inshore coastal waters, and the Arctic. They include decreased reproductive success, gross congenital abnormalities and interference with developmental/regenerational processes; thyroid dysfunction; metabolic abnormalities; feminization/demasculinization; alterations in sex ratios; altered brain development and behaviour; and altered immune function. These sublethal effects have the potential to alter an individual's quality of life, its survival, or reproductive fitness. Morbidity and mortality are rarely detected and grossly underestimated in wildlife populations and we are likely to have underestimated the occurrence, prevalence and severity of endocrine disruption in wildlife. There is no formal existing program in Canada for gathering long-term evidence for determining trends in the incidence and severity of effects in organisms. All of the information on endocrine disruption in Canadian wildlife reported in this review was gathered as a result of academic research or research-based monitoring. Much greater effort must be made to systematically detect and identify a much broader range of man-made chemicals, both persistent and nonpersistent, and their metabolites in wildlife tissues and environmental media. These efforts should be complimented by parallel measurements of various biological activities of extracts of the same wildlife tissues and environmental media. This monitoring information would then point to specific locations, effluents, agricultural practices, industrial processes, and products where investigations of effects should be conducted and to species and functions potentially at risk.
Endocrine Disruption and Human Reproductive Effects: An Overview
Authors: Foster Warren G.
Published: May 2018

Humans of all ages interact with their environment on a daily basis and are thus exposed to a variety of both man-made and naturally occurring chemicals through the air they breath, the water they drink and the food they eat. The potential for exposure to environmental contaminants to impact the function of the reproductive system and affect normal development of the reproductive tract has become an area of increasing concern at all levels of society. Environment Canada and Health Canada jointly organized a workshop to review the current state of knowledge on endocrine disrupting compounds (EDCs) and to establish a national science agenda on the scientific assessment of EDCs. This report summarizes the key scientific literature pertaining to the role of EDCs in a number of selected human reproductive/developmental outcomes. Change in the frequency of health outcome trends, epidemiological evidence of an association between the health outcome of concern and exposure to EDCs, and mechanistic evidence of receptor-mediated effects were the criteria used to evaluate the strength of the evidence. While it cannot be concluded that EDCs cause reproductive effects in the general Canadian population, the weight of evidence provides cause for continued concern.
Assessment of the Effects of Endocrine Disrupting Substances in the Canadian Environment
Authors: Munkittrick Kelly R.
Published: May 2018

Endocrine disruptors are a complex issue that continues to evolve. From a government perspective, the issue of endocrine disruptors is complicated by the inclusion of several related issues, making it difficult to deal with in an effective manner. The sub-issues probably need to be dealt with through different regulatory mechanisms. The endocrine disruptor issues can be divided into three main categories: a) issues associated with subtle responses to compounds that are persistent, lipophilic and capable of biomagnification; b) issues associated primarily with non-persistent and relatively hydrophilic substances in industrial and municipal effluents; and c) issues associated with screening existing and new chemicals for their capability of interacting with the endocrine system in an adverse manner. This paper discusses options for dealing with chemicals found in complex mixtures such as pulp mill effluents, sewage effluents and in-use agricultural chemicals. When studies documented potential concerns about the potential for pulp mill effluents to cause reproductive and endocrine changes in fish, the Government of Canada developed an Environmental Effects Monitoring program as part of the new regulatory package. The EEM program is designed to provide information on whether effects are present in the environment when industry complies with their regulated discharge requirements. Endocrine disruptors have the potential to cause environmental effects with other regulated effluents, and an EEM-type of approach would be capable of identifying situations where effects are present and need to be dealt with.
Socio-Economics of Remediating Contaminated Sediment for the St. Clair River Area of Concern
Authors: Rivers Ray
Published: May 2018

Of the total amount of contaminated sediment in the upper stretch of the St. Clair River, there are approximately 4500 cubic meters of sediment contaminated by mercury and organic chemicals that represent five of the remaining seven impaired uses in the St. Clair River Area of Concern. This material is the result of industrial pollution over a number of years in the Sarnia, Ontario, “Chemical Valley” and has most likely entered the St. Clair River via a surface drain passing through an industrial landfill. Scientific studies indicate that the contaminated material is constantly migrating downstream and has a potential for significant releases from large vessel traffic propeller wash or ice action. This paper examines two remediation options in the light of the potential benefits from a cleanup of the contaminated sediments. While not a typical benefit-cost analysis, this study explores the relationship between remediation and the social and economic benefits associated with “delisting” of the St. Clair River as an Area of Concern. The study has implications for other Areas of Concern that have sediment-related problems and require remedial action to meet the goals of the Great Lakes Water Quality Agreement.
Contaminated Sediment Management: the Canadian Experience
Authors: Santiago Roger , Pelletier Jean-Pierre
Published: May 2018

Since the beginning of North America's industrialization, the Great Lakes have been negatively impacted by the discharge of industrial, agricultural and municipal pollutants. The governments of Canada and the United States have recognized that the accumulation of pollutants within the bottom sediment and the water column has had a detrimental effect on the Great Lakes ecosystem. In 1972, Canada and the United States signed the Great Lakes Water Quality Agreement, which established common water quality objectives and commitments to programs and other measures to achieve these objectives. This included measures for the abatement and control of pollution from dredging activities. By 1985, the International Joint Commission, a body established by the two countries to provide advice on boundary water issues, identified 43 Areas of Concern where impaired water quality prevented full beneficial use of rivers, bays, harbours and ports. The Great Lakes Water Quality Agreement, amended in 1987, committed both countries to concentrate remediation efforts in these 43 Areas of Concern. This led to the development of Remedial Action Plans to assess and remediate contamination problems. Contaminated sediment was identified in all of these Areas of Concern. In 1989, the Canadian government created the 5-year $125-million Great Lakes Action Plan in support of the Great Lakes Water Quality Agreement. Of this, $55 million was allocated to the Great Lakes 2000 Cleanup Fund for the 17 Canadian Areas of Concern. A portion of the Cleanup Fund was designated for the development and demonstration of technologies for assessment, removal and treatment of contaminated sediment. Since its creation, the Remediation Technologies Program, established under the Cleanup Fund, has successfully performed 3 full-scale remediation projects, 11 pilot-scale technology demonstrations and 29 bench-scale tests. In addition to these projects, the program also evaluated existing sediment management practices and processes.
Identifying and Assessing the Economic Benefits of Contaminated Aquatic Sediment Cleanup
Authors: Dewees Donald N. , Schaefer Karl A.
Published: May 2018

A review of the literature indicates that there are very few quantitative analyses of the economic benefits associated with the cleanup of contaminated aquatic sediment. This is largely attributable to the paucity of post-project monitoring and therefore yields limited data on the link between sediment remediation and ecological benefits. Nevertheless, both the potential ecological and economic benefits are thought to be considerable. This paper identifies the types of potential economic benefits that may result from aquatic sediment remediation, assesses the utility of existing economic valuation tools for sediment cleanup specifically, highlights methodological challenges and identifies areas for further work.
Productivity of the Psammic Algal Communities in the Near-Shore Zone of the Mesotrophic Lake Piaseczno (Eastern Poland)
Authors: Czernaś Krzysztof
Published: May 2018

From 1986 to 1998, the primary productivity of psammic algae was investigated in the psammolittoral of Lake Piaseczno, a mesotrophic lake. The oxygen method was developed for the direct measurement of primary production of these algae based on light and dark bottles without disturbing the subsoil structure. This productivity was also estimated in an indirect way by measurement of chlorophyll a concentrations. The productivity of phytoplankton was also measured in the same zone. The correlation between the productivity of algae and the concentration of nutrients and major ions in water was calculated. During the study period, the highest production was found in the eupsammon (31.1 to 187.7 Cass·m-2·h-1), with the hydropsammon being lower (9.6 to 100.6 Cass·m-2·h-1). For phytoplankton biomass, the numbers were very low, which is typical of pristine lakes. The chlorophyll a concentration during the study period demonstrated a different pattern ranging from 53 mg·m-2 in the hydropsammon to 765 mg·m-2 in the eupsammon. The assimilation number for these communities was always <1. A positive (r >0.4) correlation was found between the primary production of the eupsammon and the psammolittoral phytoplankton, and the concentration of NH4-N, NO3-N, Ntot, PO4-P, Ptot. and K+ in the piezometer groundwater. No correlation was found between primary production, chlorophyll a concentration and the concentration of nutrients and major ions in the piezometer groundwater and psammolittoral water.
A Combined Chemical Reduction and Biological Oxidation Process for the Treatment of Textile Wastewater
Authors: Podeh Mohammad R. Haghighi , Sarhadi Mitra , Ghoreishi Seyyed M.
Published: May 2018

We report on the effectiveness of a combined reduction-biological treatment system for the decolourization of non-biodegradable textile dyeing wastewater. In this treatment system a bisulfite-catalyzed sodium borohydride reduction followed by activated sludge technique was used in order to remove the colours at ambient temperature and pressure. This experimental investigation consisted of two major parts: reduction treatment and biological oxidation. Both synthetic and actual wastewaters were used in this research. Synthetic wastewaters were made by several groups of dyes such as direct, basic and reactive colours. Actual wastewaters were collected from two different textile industries in the city of Isfahan, Iran. The characterization of raw and treated wastewater was carried out by infrared and ultraviolet spectrometers. The ASTM-E450-82 method was used to measure the colour. The results of this study demonstrated that this biological treatment technique decreased colour, BOD, COD and TSS by 74 to 88%, 97 to 100%, 76 to 83% and 92 to 97%, respectively. The IR and UV analyses showed that nonbiodegradable dyes are converted to biodegradable organic compounds such as alkyl and alkens. Another major advantage of this method with respect to other methods, namely, adsorption and coagulation, was that it removes colour without causing any disposal problem. The optimum dosage for treatment of actual wastewaters was found to be 50 to 60 mg/L for catalyst bisulfite and 200 to 250 mg/L for sodium borohydride. Finally, a benchscale experimental comparison of this technique with other combined chemical and biological methods currently used showed higher efficiency and lower cost for the newly developed technique.
Monitoring of Activated Sludge Systems Using a Combination of Specific Oxygen Uptake Rates and Specific Adenosine Triphosphate Measurements
Authors: Bergeron Janique , Paice Michael
Published: May 2018

Two five-litre activated sludge (AS) bioreactors were operated for several months to demonstrate potential mill applications of a four-assay set, which has been proposed as a tool for monitoring the health of the AS microbial population. The set consists of three specific oxygen uptake rate (SOUR) determinations at different substrate concentrations (SOURat, SOURnmax and SOURtox where at, nmax and tox are defined as aeration tank, near maximum, and toxic, respectively), and a specific adenosine triphosphate (SATP) assay. Two disturbances were applied at different times to an AS system treating kraft effluent. First, temperature was increased from 25 to 40°C, and second, a black liquor spill was simulated. The data before, during, and after these disturbances were statistically analyzed. From this analysis, we concluded that the four-assay set could be used as a microbial health characterization (MHC) tool. It allows an operator to correlate microbial changes with operating data over a mediumterm time scale. We compared the values obtained during periods of upset in the system treating the kraft effluent, to the baseline data set determined from stable operation periods. This demonstrated how the four-assay set could be used as a biological early warning (BEW) tool. It allows a treatment system operator to make appropriate adjustments immediately after detecting values that fall outside the baseline data range.
Fractal Analysis of Pore Distributions in Alum Coagulation and Activated Sludge Flocs
Authors: Gorczyca Beata , Ganczarczyk Jerzy
Published: May 2018

The information on floc porosity is essential for estimation of the permeability of the aggregate. The average porosity of alum and activated sludge flocs determined in this study on thin sections of the aggregates was similar, varying in the range from 8 to 9%. Similar porosity of the two different types of aggregates suggested that the permeability of these flocs could also be similar. However, the experimental observations of floc settling rates and floc shape factors did not support this expectation and led to a conclusion that the permeability of an aggregate cannot be estimated based on the average geometric porosity of a floc only. When the size distributions of pores on flocs' sections were analyzed using the concept of fractal geometry, different characteristic values for alum coagulation and activated sludge flocs were found. Larger pore size found in activated sludge flocs allows for more flow through these flocs. Therefore, the size of characteristic pores rather than the average total porosity determines the permeability of an aggregate.
Acid Hydrolysis Lignin as a Sorbent for Naphthalene
Authors: Keane Angela , Ghoshal Subhasis
Published: May 2018

Lignin, a major polymeric constituent of woody plant tissue, is an abundant source of natural organic matter available as a waste product from the pulp and paper and the fuel ethanol industries. In this study, the sorptive capacity of acid hydrolysis lignin for naphthalene, a representative nonpolar hydrophobic organic compound (HOC), was investigated. When powdered lignin is mixed with distilled water, dissolved and/or colloidal organic matter leaches into the aqueous phase imparting a cloudy yellowish colour. A washing and filtering protocol was developed for pretreating the lignin employed in the sorption studies. Results from batch sorption experiments showed that acid hydrolysis lignin has a strong affinity for naphthalene. The Freundlich isotherm coefficients obtained indicate that the sorption isotherm for naphthalene on hydrolysis lignin is nearly linear. A modified Freundlich equation was employed in order to compare sorption data for HOCs on lignin and activated carbon through the use of unit equivalent coefficients. The results presented in this research and in the literature suggest that the two sorbents are comparable in terms of sorption coefficients. It was determined that acid hydrolysis lignin is unsuitable for use in a packed bed since pumping a naphthalene solution through a column packed with lignin caused the wet lignin to become significantly hardened over time, resulting in a large pressure drop across the system.
Occurrence of Butyltin Compounds in Freshwater Mussels (Elliptio complanata) from Contaminated Aquatic Areas in Ontario, Canada
Authors: Yang Fan , Maguire R. James , Chau Yiu K.
Published: May 2018

The antifouling agent tributyltin (TBT) is extremely toxic to some aquatic organisms. The accumulation of butyltin compounds in the tissues of freshwater mussels from contaminated areas in Ontario was studied in the field with caged mussels (Elliptio complanata). Mussels were placed in four sites for 11 months, and one site for 6 months, in locations of previous contamination of water and sediments. Additional cages were exposed for 5 months at two of the sites to study the effect of mussel size on accumulation. The mussels were collected at regular intervals for butyltin analysis. After almost one year of exposure at four locations, the TBT contents in tissue of mussels were 9 to 148 ng as Sn/g (wet weight). The results showed that concentrations of TBT in mussels were related to the mussel size and the concentrations of TBT in contaminated aquatic areas, and that concentrations in mussel tissue increased dramatically over winter. The results of the experiment demonstrated that caged mussels are useful for indicating the presence of TBT in aquatic systems.
Element Concentrations in Groundwater in the Eastern Phosphate Area and Southern Volcanic Area of Syria
Authors: Alhassanieh Oussama , Ghafar Mohamad , Abdul-Hadi Abdul-Rahman
Published: May 2018

The concentration of the elements K, Ca, Mg, Na, Sr, Al, As, Ba, Br, Ce, Cr, Fe, Nb, Rb, Se, Sm, V, Zn, Co, Cs, U, Sb, Sc, Th, Eu and Hf in groundwater samples from the eastern phosphate and the southern volcanic area of Syria were investigated using INAA (instrumental neutron activation analysis) and γ-spectroscopy. The concentrations of first and second group elements are higher in the phosphate area than in the volcanic area. The concentrations of Fe, Co, Cr, Sc, Eu and Sm are high in some samples from the southern volcanic area. This can be explained by the occurrence of these elements in surrounding rocks and the solubility of their compounds. The results are compared with drinking water limits from different countries.
Thallium Contamination of Water in Canada
Authors: Cheam Ven
Published: May 2018

Thallium is highly toxic but has been an obscure element compared to its three popular neighbours, lead, mercury and cadmium. It is partly due to the scarcity of its analytical data, caused by its high analytical detection limit relative to the other three elements and by its generally low level in the environment. We have developed a highly sensitive instrument, a Laser-Excited Atomic Fluorescence Spectrometer, to study thallium contamination in some important Canadian ecosystems from the Arctic (containing very low thallium concentration) to coal-related industries across Canada and even to the study of thallium toxicity in an invertebrate, Hyalella azteca. Overall, our data indicate that the coal power plants and mines contain higher thallium concentrations than the other ecosystems studied, and the eastern region has the highest Tl concentrations compared to other regions. The range of thallium concentration in ng/L for the Arctic snow and ice was between not detected and 8.4, for the Great Lakes waters 0.9 to 48, for pore waters 0.1 to 213, for western coal power plants and mines 0.1 to 1326, for central coal power plants 1.2 to 175, for eastern coal power plants and mines 0.2 to 23605, and for miscellaneous sites across Canada not detected to 4390 ng/L. Some of these high concentrations and those high ones reported in industrial wastewaters exceeded the chronic toxicity endpoints for Hyalella azteca mortality, growth and reproduction, thus can cause serious distress to the environment. All data were integrated into a map of thallium distribution, the first one in Canada. Natural background level of thallium for the Arctic was estimated to be 0.02 to 0.03 pg/g.
Sublethal Toxicity Findings by the Pulp and Paper Industry for Cycles 1 and 2 of the Environmental Effects Monitoring Program
Authors: Scroggins Richard P. , Miller Jennifer A. , Borgmann Anne I. , Sprague John B.
Published: May 2018

Sublethal toxicity tests successfully measured the improved quality of pulp mill effluents from the first cycle of environmental effects monitoring (1992–1996) to the second cycle (1997–2000). Test endpoints showed notable shifts to higher concentrations (less toxic). During the second cycle of monitoring, significantly more tests showed no effect in full-strength effluent. Five case studies were considered as part of this exercise. Most of the improvement came with installation of secondary treatment. Twelve Ontario mills with secondary treatment showed reduced toxicity, compared to results with primary treatment. All 29 sets of sublethal data showed higher IC25s during the second cycle, and 23 of these differences were statistically significant. Any other changes between the two cycles of study caused only marginal overall improvement in toxicity, judging by 12 freshwater mills in British Columbia which had secondary treatment during both cycles. Sublethal tests successfully predicted the zone of potential effect in receiving water, agreeing with effects observed in biological surveys. Overlapping zones from multiple discharges could also be demonstrated. In a situation near Niagara Falls, sublethal tests estimated the proportions of toxic loading that four mills contributed to one water body. The prediction was realistic; the actual toxicity found for a mixed effluent was 57% of that predicted from separate toxicities. The conservative prediction agrees with the usual less-than-additive sublethal action of combined toxicants.
Development of a Monitoring Design for Examining Effects in Wild Fish Associated with Discharges from Metal Mines
Authors: Ribey Sandra C. , Munkittrick Kelly R. , McMaster Mark E. , Courtenay Simon , Langlois Claude , Munger Steve , Rosaasen Arden , Whitley Gerry
Published: May 2018

As part of the amended Metal Mining Liquid Effluent Regulations under the Fisheries Act, mines will be required to develop and conduct Environmental Effects Monitoring (EEM). EEM will be done to evaluate the effects of mine effluent on fish, fish habitat, and fish usability. Mines will be required to determine if there are changes in fish populations and/or in the usability of fish due to mine effluent. The EEM program has been designed with a tiered monitoring approach, with the first phase determining if an effect is present. Subsequent phases of EEM will focus on continued monitoring and determining the magnitude, geographic extent, and cause of effects (if any). Fish collected from the area exposed to mine effluent will be compared to fish from a reference area in order to determine if there is an effect, if the effect is mine related and the cause of the effect within the effluent. The fish population survey will examine the growth, reproduction, condition, and survival of one or more resident sentinel fish species. Fish usability will be determined based on the appearance of fish, their use, and the contaminant levels in fish tissue. It is recognized that some mines may not be able to implement a fish monitoring program as outlined, so it has been recommended that alternative methods, such as a caged bivalves or on-site bioassays, may also be used. Frequency of monitoring will be dependent on the previous results of the fish and benthic invertebrate monitoring phases.
L'enlèvement biologique du phosphore dans les technologies à biofilm : une synthèse de la problématique
Authors: Zelovic Tanja Baljic , Leduc Roland
Published: May 2018

Cet article synthétise l'état actuel des connaissances sur l'application de la technologie du biofilm pour l'enlèvement biologique du phosphore (EBP). Il présente d'abord les principaux mécanismes de l'EBP, ensuite les caractéristiques du procédé à biofilm, et poursuit avec celles qui sont favorables pour la réalisation de la biodéphosphatation. Les différentes configurations du processus de biodéphosphatation par biofilm étudiées à ce jour sont présentées, ainsi qu'une révision des facteurs particuliers qui influencent l'EBP dans un biofilm. Une attention particulière est apportée aux processus opérant en continu.
Analysis of Surface Water Quality in Tehran
Authors: Asadollah-Fardi Golamreza
Published: May 2018

Box-Jenkins and exponential smoothing time series analysis of the monthly water quality in surface water in Tehran was conducted as a case study. Various univariate models were developed for each determinand. Most of the models were seasonal, indicating that the water quality determinands vary throughout the year. The models follow the same pattern of variations present in the data. This study shows the credibility of the models, therefore the models may be used for future design purposes.
Optimizing the Management of Soil Erosion
Authors: Nikkami Davood , Elektorowicz Maria , Mehuys Guy R.
Published: May 2018

To reduce the environmental and economical impact of soil erosion resulting from improper management of land-use activities, a study was initiated by the Iranian Ministry of Construction on Syahrood, one of the sub-basins of the Damavand watershed in Iran. Land-use optimization is one of the appropriate strategies for soil conservation. It can empower the decision maker or watershed manager to choose from different land-use scenarios to reach the best decision with the different combinations of variables.

The output results of the sediment yield model, including the integration of the Modified Universal Soil Loss Equation (MUSLE) with Spatial Analysis System-Geographic Information System (SPANS-GIS), along with the net income of each land use were used as input in the land-use optimization model for minimizing the sediment yield and maximizing farm production of each land use. The multi-objective linear programming simplex method of Steuer (1995) was used to solve the problem. The optimization process allocated dryland farming areas to rangelands if no changes were made to the current supporting practice system. The expected annual sediment yield from the entire sub-basin was reduced by 2420 tonnes/year (or by 5%) and the annual net farm income was increased by 3.99 billion Iranian Rial/year (or by 134%).
Concentrations of Some Lipophilic Chemicals in Fresh Water May Be Underestimated by Conventional Dichloromethane Extraction
Authors: Maguire R. James , Comba Michael E. , Cannon Christina M.
Published: May 2018

A re-analysis of water samples collected to determine the occurrence of lipophilic organochlorine chemicals, total polychlorinated biphenyls (PCBs) and polynuclear aromatic hydrocarbons (PAHs) in six tributaries to Lake Ontario in 1997 to 1998 has shown relatively high concentrations of some of those chemicals in extracts of chromic acid-digested water after the water had been extracted at neutral pH. For organochlorine chemicals and PCBs the effect was dramatic—for some tributaries the sums of concentrations of the chemicals in the acidic extracts over all sampling dates were larger than the sums of concentrations of the chemicals in the (neutral) water plus suspended solids fraction that had been determined previously. In addition, some chemicals were found in the acidic extracts that were not found in the prior extracts of (neutral) water plus suspended solids. Although some individual PAHs were found at relatively high concentrations in the acidic extracts compared to extracts of (neutral) water plus suspended solids, in general the phenomenon was not significant for total PAHs. The implication of our finding is that conventional dichloromethane extraction of neutral (filtered) water and the suspended solids phases can significantly underestimate the concentrations of some lipophilic chemicals such as chlorinated hydrocarbons and PCBs in fresh water, leading to an underestimation of their loadings to aquatic ecosystems. However, it should be noted that the biological availability of chemicals that are only extractable after rigorous extraction of the water may be doubtful.
The Effect of Nozzle Type on Air Entrainment by Plunging Water Jets
Authors: Bagatur Tamer , Baylar Ahmet , Sekerdag Nusret
Published: May 2018

In this study, for the plunging water jet aeration system using various inclined nozzle types, bubble penetration depth, air entrainment rate, water jet expansion, effect of water jet circumference at impact point, oxygen transfer coefficient and oxygen transfer efficiency which changed depending on the water jet velocity, were researched in an air-water system. Numerous studies were conducted with circular nozzles. The present study describes new experiments performed with different nozzle types. Three types of nozzles were examined, i.e., those with circular, ellipse and rectangle duct with rounded ends. Experimental results showed that water jets produced with ellipse and rectangle duct with rounded ends nozzles have very different flow characteristics, entrainment patterns on free water jet surface, and submerged water jet region within the receiving tank. Higher air entrainment rate and oxygen transfer efficiency was observed in the rectangle duct with rounded ends nozzle due to water jet expansion. Bubble penetration depth, however, is lower for the rectangle duct with rounded ends nozzle than for the other nozzles. The ellipse nozzle provided the highest bubble penetration depth. These results showed that it is appropriate to use ellipse nozzle in aeration of deep pool and rectangle duct with rounded ends nozzle in the applications where high bubble concentration is desirable.
Estimation of Bench-Scale Chlorine Decay in Drinking Water Using nth-Order Kinetic and Back Propagation Neural Network Models
Authors: Rodriguez Manuel J. , Milot Julie , Sérodes Jean-Baptiste , Pacaud Adèle
Published: May 2018

This paper presents the development of two models for simulating residual chlorine decay in raw and treated waters collected from six different utilities of the Quebec City area. The data for modelling was generated by means of several bench-scale chlorination assays undertaken with chlorine doses that varied according to the content of natural organic matter in the water. The first model is a classical kinetic model in which chlorine decay is represented by a first or a second order function, according to the contact time of chlorine. A decay coefficient is estimated based on water quality and operational parameters, using linear regression. The second is a non-linear back propagation neural network model in which all the parameters responsible for chlorine decay are processed within a single model. The performances of both models were evaluated and compared using the database for model development and an independent database for validation. Both models demonstrated acceptable abilities for simulating residual chlorine decay. However, the back propagation neural network model gave significantly better results for conditions involving high chlorine dosage, high organic matter content and long reaction times during chlorination experiments. In the other cases, the performance of the kinetic model was slightly superior. Back propagation neural networks are also advantageous because they do not require assumptions about model order or the estimation of a chlorine decay coefficient. Also included in the paper is a discussion of possible strategies for use in future research work in order to generalize the results obtained.