10 research outputs found
Removal of sugars from food and beverage wastewaters by amino-modified SBA-15
No full textIn the context of the removal of the biochemical oxygen demand (BOD5) from food and beverages production wastewaters, this paper reports the capabilities of SBA-15 modified with (3-aminopropyl)-triethoxysilane (S-APTES) and N-[3-(trimethoxysilyl)propyl]aniline (S-Aniline) in the removal of glucose, fructose and sucrose at very high concentrations (350,000 mg/L for glucose, 350,000 mg/L for fructose and 170,000 mg/L for sucrose), i.e. the sugars most widely used as sweeteners in food and beverage manufacturing. After the determination of the main physico-chemical characteristics, the study of the effect of pH on the removal capabilities of S-APTES and S-Aniline allowed to elucidate the main mechanisms involved. Based on the study of solid:liquid ratio, the optimal experimental conditions were defined to achieve a removal of BOD5 in simulated soft-drink wastewater as high as 80%. The results show that a lower adsorbent dosage is required in respect to current methodologies, representing an advantage especially for disposal procedures of the exhausted adsorbent. This work offers a proof of concept for the integration of amino-modified SBA-15 sorbents in industrial pre-treatment of wastewaters before discharging it in sewerage systems
Encapsulation of the glyphosate herbicide in mesoporous and soil-affine sorbents for its prolonged release
No full textThe increase in herbicide consumption, in particularly glyphosate, is causing considerable health and environmental concerns, due to its possible carcinogenic effects. Indeed, its widespread and intensive use promotes its diffusion in the surrounding environment. Additionally, the operator's exposure to the herbicide is not negligible.In this work the encapsulation of glyphosate into three selected, eco-friendly silica-and clay-based supports, namely SBA-15, montmorillonite (MMT) and Al pillared montmorillonite (Al-MMT) to promote both a punctual application and a prolonged release of glyphosate is innovatively presented.Preliminary, substrates were characterized pre and post encapsulation through XRD and nitrogen adsorption measurements, to assess the incorporation of the herbicide. Release studies were performed in aqueous matrices of different composition, namely ultrapure water, 0.02 M oxalic pH 3 (simulating acid rains) and 0.01 M CaCl2 solution (simulating soil salinity). Within all these media, Al-MMT exhibited a slow-releasing mechanism, with about 10-20% of glyphosate still retained on the support after 7 days, ascribed to complexation and electrostatic interactions.Three different kinetic models usually applied within controlled-releasing processes, i.e. zero order, pseudo first order and Korsmeyer-Peppas models, were used to describe glyphosate release from Al-MMT in CaCl2 solutions, with Korsmeyer-Peppas model providing the best fit to experimental data (R2 > 0.990). Finally, a water/ soil bench-scaled system was efficiently tested, confirming the successfully applicability of Al-MMT in the prolonged release of glyphosate in real systems
The Moral Problem of Economic Inequality: An Analysis of the Roman Catholic and the Quaker Traditions
No full textIn this project I have explored the moral significance of inequalities of income and wealth through an historical examination of the Roman Catholic and the Quaker traditions' definitions, interpretations, and analyses of economic inequality. One of my concerns has been to enhance the moral force of arguments against increasing inequality (or stated positively, to enhance the moral arguments for relative economic equality). As sources for moral arguments against inequality, I turned to the teaching documents of the Roman Catholic and Quaker branches of Christianity. I chose to draw on these two traditions because of their longstanding and visible commitments to working for social justice and also because of the striking differences in their organizational structure. The Catholic and Quaker traditions turned out to be instructive in an unexpected way – both evaded the problem of inequalities of income and wealth. While the two traditions evaded the particular problem of inequality of income and wealth, both have conceptual resources which can be utilized to mount a vigorous critique of economic inequality both internally and in the public sphere. The resources within the Roman Catholic tradition that could and should contribute to an ethic of relative economic equality include an egalitarian theological anthropology, the principles of universal destination of goods and the right use of property, the virtue/value of solidarity, the value of participation, and a theology of work. The resources within the Quaker tradition that could and should contribute to an ethic of relative economic equality include the testimonies of equality, peace, simplicity, and stewardship as well as Quaker decision-making processes and a Quaker spirituality of work. In this project, I have been most concerned to show how the traditions can and should generate more internal dialogue about the problem of inequality. I have proposed the development of Catholic and Quaker theologies of equality as the foundation for robust ethics of relative economic equality. The development of theologies of equality would also, importantly, be an opportunity for and a means to mounting an integrative theo-ethical critique of the interconnected inequalities associated with race, gender, and class
Characterization techniques as supporting tools for the interpretation of biochar adsorption efficiency in water treatment: A critical review
No full textOver the past decade, biochar (BC) has received significant attention in many environmental applications, including water purification, since it is available as a low-cost by-product of the energetic valorisation of biomass. Biochar has many intrinsic characteristics, including its porous structure, which is similar to that of activated carbon (AC), which is the most widely used sorbent in water treatment. The physicochemical and performance characteristics of BCs are usually non-homogenously investigated, with several studies only evaluating limited parameters, depending on the individual perspective of the author. Within this review, we have taken an innovative approach to critically survey the methodologies that are generally used to characterize BCs and ACs to propose a comprehensive and ready-to-use database of protocols. Discussion about the parameters of chars that are usually correlated with adsorption performance in water purification is proposed, and we will also consider the physicochemical properties of pollutants (i.e., Kow). Uniquely, an adsorption efficiency index BC/AC is presented and discussed, which is accompanied by an economic perspective. According to our survey, non-homogeneous characterization approaches limit the understanding of the correlations between the pollutants to be removed and the physicochemical features of BCs. Moreover, the investigations of BC as an adsorption medium necessitate dedicated parallel studies to compare BC characteristics and performances with those of ACs
Biochars intended for water filtration: A comparative study with activated carbons of their physicochemical properties and removal efficiency towards neutral and anionic organic pollutants
No full textRegulated and emerging disinfection by-products in drinking waters: challenges and efforts in their analytical determination
No full text
Encapsulation of the glyphosate herbicide in mesoporous and soil-affine sorbents for its prolonged release
No full textForecasting and inventory control for hospital management
No full textThis thesis was submitted for the degree of Doctor of Philosophy and was awarded by Brunel University.Economic stringencies have compelled Canadian
hospitals to examine their administrative effectiveness
critically.
Improved supplies and inventory procedures adopted
by leading industrial corporations, suggest that
hospitals might benefit from such systems. Lack of the
profit incentive, and the high ratio of wages to total
expenses in hospitals, have delayed adoption of modern
inventory management techniques. This study examined the
economic status of Canadian hospitals, and endeavoured to
discover whether a computer-based inventory management
system, incorporating short-term statistical demand forecasting,
would be feasible and advantageous.
Scientific forecasting for inventory management
is not used by hospitals. The writer considered which
technique would be most suited to their needs, taking
account of benefits claimed by industrial users. Samples
of demand data were subjected to a variety of simple
forecasting methods, including moving averages, exponentially
smoothed averages and the Box-Jenkins method.
Comparisons were made in terms of relative size of forecast
errors; ease of data maintenance, and demands upon
hospital clerical staffs. The computer system: BRUFICH
facilitated scrutiny of the effect of each technique upon
major components of the system.
It is concluded that either of two methods would
be appropriate: moving averages and double exponential
smoothing. The latter, when combined with adaptive control
through tracking signals, is easily incorporated
within the total inventory system. It requires only a
short run of data, tracks trend satisfactorily, and
demands little operator intervention.
The original system designed by this writer was
adopted by the Hospital for Sick Children, Toronto, and
has significantly improved their inventory management.Lakehead University and the Ministry of Health, Government of Ontario
