bluuebunny/crossref_metadata_2025 huggingface dataset:
The Impact of Materiality Decisions on Financial Ratios: A Computer Simulation
Authors: Turner Jerry L.
Published: January 2017

This study examines the extent to which immaterial uncorrected errors may combine to affect specific financial ratios. A simulation is performed in which three balance sheet accounts and three related income statement accounts are seeded with immaterial errors. The magnitudes of the errors are controlled so the financial statement account balances are materially correct both individually and in the aggregate. The study examines six materiality heuristics for each of three industry classifications and three different error distribution patterns. For each heuristic/industry combination and error distribution pattern, a 95 percent confidence interval is generated for nine financial ratios.

Results indicate that immaterial errors may combine to create substantial variances in some ratios. Profitability ratios based on income statement accounts display wide confidence intervals, while solvency ratios based on balance sheet accounts display relatively narrow intervals. Comparison between a standard normal distribution and a nonsymmetrical error distribution indicates that ratio variances are substantial and sensitive to error patterns even when errors are immaterial. Tests for equality of variances identify significant differences between heuristic methods and between industries. When making the decision regarding requiring entry or waiving discovered errors, the auditor should consider the impact of such errors not only on financial statement balances, but on the ways users may combine those balances.
Environmental Information and Market Reactions to Environmental Legislation
Authors: Blacconiere Walter G. , Northcut W. Dana
Published: January 2017

Environmental issues have attracted national attention and are becoming a focus at many firms. This paper examines the relation between stock price reactions to the Superfund Amendments and Reauthorization Act (SARA) of 1986 and environmental information. We include alternative information sources in a test of the value relevance of environmental data. We find some evidence that chemical firms with more extensive environmental disclosures included in their 10-K reports had a less negative reaction to SARA, while firms with greater exposure to Superfund costs (based on EPA data) had a more negative market reaction. A primary contribution of our research is the finding that both financial statement environmental disclosures and estimated Superfund costs have incremental value relevance.
Stranded Costs and Competitive Forces in the Electric Utility Industry
Authors: Blacconiere Walter G. , Johnson Marilyn F. , Johnson Mark S.
Published: January 2017

It is likely that deregulation of the electric utility industry will force high-cost electric utilities to write off the “stranded” cost of plant and equipment that would be rendered obsolete in a competitive marketplace. In this paper, we examine the financial statement analysis implications of ongoing deregulation. Based on 1993 data for a sample of 111 large investor-owned electric utilities, our analyses suggest that it is possible to use financial statement data to form estimates of these potentially stranded costs. In addition, we find that recent trends toward deregulation are associated with an increase in the significance of the firm's cost structure in explaining the relation between market values and book values of equity.
Discussion: “Stranded Costs and Competitive Forces in the Electric Utility Industry”
Authors: White Lawrence J.
Published: January 2017

Stranded costs in the electric utility industry—the past costs incurred by incumbent utilities that could not be recovered in a competitive market environment—have been a troubling and troublesome policy issue for electricity deregulation. Although electricity deregulation surely would have proceeded slowly in any event,1 the stranded cost question— who (customers? shareholder-owners?) will absorb the losses in the forthcoming competitive environment?—has clearly slowed the process even further.
CEO Compensation in a Regulatory Environment: An Analysis of the Electric Utility Industry
Authors: Bryan Stephen , Hwang LeeSeok
Published: January 2017

Prior studies argue that a firm's investment opportunity set affects the level of information asymmetry and thereby the structure of CEO compensation. We test whether the political constraints imposed in a regulatory environment incrementally affect both the level and the structure of CEO compensation, while controlling for the effects of investment opportunity set and other firm characteristics. We hypothesize that increased political constraints reduce the need and the opportunity to pay management bonuses, stock options, and other incentive-based compensation, in addition to a base salary. We test our hypothesis using CEO compensation data from electric utility companies during 1990–1995. We develop refined measures for different levels of regulation and monitoring within the electric utility industry. Our results provide evidence that increased political constraints affect both the level and structure of CEO compensation, after controlling for investment opportunity set and other firm characteristics, such as firm size, systematic risk, and performance.
Accounting Estimation Disclosures and Firm Valuation in the Property-Casualty Insurance Industry
Authors: Anthony Joseph H. , Petroni Kathy R.
Published: January 2017

Accounting earnings are subject to estimation error. Under GAAP, corrections to estimates are included in current and future earnings, but characteristics of previous errors are not disclosed. An exception exists for property-casualty insurers. SEC mandated disclosures reveal errors in previous claim expense estimates as well as the correction for those errors in current earnings. An important issue is whether these detailed disclosures are value-relevant.

We examine the information content of the SEC disclosures by testing their valuation implications. We investigate whether estimation errors in previous earnings influence the reflection of current earnings in price. Results suggest that investors use these disclosures in valuation decisions. Insurers with more variable estimation errors have smaller earnings response coefficients. Apparently investors assume that the precision of previous earnings is indicative of the precision in current earnings. We also find that stock returns are associated with revisions of previous estimations included in current earnings. Our research has implications for regulation, suggesting that similar disclosures should be considered for other estimates.
Market Implications of Regulatory Form in the Electric Utility Industry: An Assessment of Incentive Regulation
Authors: Nwaeze Emeka T. , Mereba Janice R.
Published: January 2017

In this study, we investigate whether incentive regulation (IR) is associated with improvements infirm performance. We also examine the effect of IR type on the information contents of earnings and cash flows. The empirical analysis uses price-to-book ratio, earnings, and cash flows as the empirical proxies of firm performance. The analysis also controls for the potential effects of firm size and regulatory climate on the results. We find that firms operating under IR exhibit improvements in each of the performance metrics. It is shown that the information contents of earnings and cashflows for the price-to-book ratio are higher for IR than for non-IR firms, after controlling for the effects affirm size and regulatory climate. The results also reveal that variation in IR type is associated with differences in the information contents of earnings and cash flows. We also find that, prior to the introduction of IR, the performances of IR and non-IR firms are not fundamentally different.
Discussion: “Involuntary Benchmarking and Quality Improvement: The Effect of Mandated Public Disclosure on Hospitals”
Authors: Banker Rajiv D.
Published: January 2017

This paper addresses an important empirical question: Does the mandated public disclosure of quality information cause predictable changes in managerial behavior? Evans et al. find that a new requirement for the disclosure of relative performance measures for Pennsylvania hospitals results in hospitals with higher quality (lower mortality rates) gaining market share. Anticipating this customer reaction, those hospitals with poorer quality levels, those facing more intense competition, and those small in size exhibit a greater improvement in their quality performance. However, the hospitals with higher mortality rates also exhibit the least improvement in productivity (as measured by length of stay).1
A Technique for Evaluating Sepsis in TPN Patients
Authors: Macht Steven D.
Published: January 2017

Sepsis continues to be one of the most feared complications of total parenteral nutrition. Many techniques have been advocated for dressing changes, solution preparation, and evaluation of patients with fever spikes. Our technique in evaluating such a patient with suspected sepsis is to remove the tubing and solution from the pumping mechanism and place the bottle below the patient, permitting approximately 10 cc of blood to flow into the tubing. The entire set‐up of solution and tubing is then quickly replaced and the infusion resumed. The removed blood is transferred to a series of three standard blood culture bottles. The first bottle will be culturing blood; the second, a mixture of blood and infusate; the third, solution alone. When performed carefully, negative culture results appear to exclude TPN as a source of sepsis. Positive results are obviously helpful, but must be interpreted with caution in that the blood, catheter, tubing, filter, or solution may be suspect.
Area Wide Nutritional Support Service
Authors: Dean Richard E.
Published: January 2017

Nutritional deficiencies have been identified as a problem of major concern to all persons involved in health care delivery. Development of nutritional services in several medical centers across the country has demonstrated the effectiveness of this program as an adjunct to improved patient care. Expansion of these benefits through an Area Wide Nutritional Support Service has been organized through a network of educational programs, organization of hospital nutrition committees, and communication links. Involvement of physicians, nurses, dietitians, and pharmacists in a Nutrition Team at the local and area‐wide level is essential to the success of the program. A Physician‐Director, Nurse‐Educator, and Dietitian in a major community medical center are responsible for the ongoing educational programs directed to physicians, nurses, and paramedical personnel in the surrounding communities and the maintenance of a model Nutritional Support Service at the medical center. Educational and research affiliations with several colleges and universities have provided a model clinical resource for the education of medical students, residents, and clinical experiences for pharmacists and dietitians.
Recall Antigen Response in Pediatric Cancer Patients Receiving Parenteral Hyperalimentation
Authors: Teitell Betsy Cohen , Herson Jay , Eys Jan Van
Published: January 2017

Delayed hypersensitivity was evaluated in 24 pediatric cancer patients who received intravenous hyperalimentation (IVH). Hypersensitivity, as analyzed by skin test antigens, was recorded before and after IVH therapy. With the exception of malnourished patients, tumor response, nutritional status, and delayed hypersensitivity were not correlated in the way suggested by similar studies in adult patients. However, hypersensitivity was correlated with nutritional status post‐IVH.
‘Are you tough enough?’ Performing gender in the UK leadership debates 2015
Authors: Harmer Emily , Savigny Heather , Ward Orlanda
Published: January 2017

Leaders’ debates have become a feature of contemporary election campaigning. While an historical feature of the US landscape, in the United Kingdom, they are a more recent phenomenon. The second UK 2015 general election leadership debate comprised seven candidates, of which three were women. Using qualitative thematic analysis and adopting the notion that gender is ‘performed’, we explore three features of coverage of the debate. First, the ways in which the debate itself was constructed as a masculine activity through a series of highly gendered metaphors; second, how newspaper frames reinforced gendered notions of masculinity and femininity in respect of political leadership; and third, how the success of women in the debates was constructed as the emasculation of their male rivals. Crucially, we focus not just on the ‘feminisation’ of women in the political arena, but also on the ways in which masculinity is posited as the criterion for the evaluation of politicians of all genders.
European Monetary Union and Optimum Currency Areas
Authors: Cooper John C.B.
Published: January 2017

Eleven European countries have now joined together in monetary union with a common currency and a common monetary policy. Whether a group of economies should form a monetary union depends upon how closely it resembles an optimum currency area. In general, an area where prices and wages are flexible or where labour moves freely or where there is a centralised fiscal policy may be viewed as an optimum currency area. However, the euro zone does not appear to meet any of these conditions.
Development Economics: An Institutional Bastion
Authors: Cameron John , Ndhlovu Tidings P.
Published: January 2017

What binds most of the disparate writings by institutional economists (broadly defined), from the earlier progenitors, such as Veblen, Keynes and Galbraith, to the modern institutionalists, including Means, Fusfield and Hodgson, is their questioning of many of the tenets of neoclassical theory. Within this same broad paradigm, there has also been an emergence of ‘new institutional economics’, whose chief protagonists are Oliver Williamson and Douglas C. North. However, for the latter, the relationship between institutions and markets across time and space starts from the basic propositions of rational individualism and competition pertaining to neoclassical economics, with the inclusion of more institutional detail than is usual for neoclassical models.

This paper seeks to explore as yet an uncharted area, that is, that development economics, from the writings of Arthur Lewis to those of Amartya Sen, has long been the bastion of institutional economics. Despite the concerted attacks by neoclassicists on the discipline in the early 1980s, development economics has never been persuaded by the strength of argument of the mainstream neoclassical case. Arguably, the common ground of development economics as an identifiable branch of the discipline has been its concern with the impact of institutional factors (cultural values in civil society, politico-bureaucratic states, global economic organisations) on resource allocation. Concepts such as dependency, unequal exchange, entitlements the neo-colonial state, urban bias, the East Asian miracle and transnational corporations have strong institutional roots. This paper will examine the shifting views on institutional factors in development economics and attempt to integrate the New Institutional Economics into a more general theory.
An Investigation of UK Companies Practices in the Determination, Interpretation and Usage of Cost of Capital
Authors: Al-Ali Jasim , Arkwright Tony
Published: January 2017

There has been extensive discussion regarding the influence of the cost of capital on the value and investment decisions of a firm.

The important role thought to be played by the cost of capital has resulted in considerable academic debate as to how the cost of capital should be calculated.

This study was designed to enhance the debate by an investigation into how firms, derive, interpret and use the cost of capital in practice.

The study adopted a survey approach to obtain information from large UK companies. Seventy three UK companies gave detailed responses revealing interesting issues for both academics and practitioners.
Book Review: Technology, Organization and Competitiveness: Perspectives on Industrial and Corporate Change
Authors: Nightingale John
Published: January 2017

Dosi, Giovanni, Teece, D.J. and Chytry, Josef, Technology, Organization and Competitiveness: Perspectives on Industrial and Corporate Change. 1998. Oxford, Oxford University Press, £45 (hardcover), £16.99 (soft).
Economics in the History Mirror
Authors: Jones E.L.
Published: January 2017

For writing economic history, standard theory is found to be excessively a priori and prone to assume away interesting phenomena. A particular defect is the lack of a mainstream theory of institutional change. Yet market analysis, although sometimes used unwisely as a substitute for historical description, does offer a standard of comparison which is absent from general history. The simpler concepts of economics also offer returns which the historian can scarcely afford to spurn.
The Empirical Appraisal of Economic Theories, Econometric Testing and the Logic of Refutation
Authors: Kamath Shyam J. , Jensen Keith Christian , Bennett Robert E.
Published: January 2017

This paper comprehensively analyses the logical problems involved in conventional tests of economic theories. It also outlines some methodological problems with current econometric practice. An alternative test procedure which constitutes a logically complete and rigorous extension of conventional test procedures is proposed in order to attenuate some of the problems identified. The test is implemented in a practical context by considering the debate over the inclusion of real money balances in the neoclassical aggregate production function.
Crime: Why don’t Economists have much to Say about it?
Authors: Burden Tom
Published: January 2017

The paper examines how crime came to be excluded from the purview of conventional economics through the legacy of the classical tradition. It looks at how the study of economic activity was consequently restricted to the examination of lawful market transactions which came to define the scope of the discipline. The paper reviews the scope of illegal economic activity by corporations, illegal businesses and private individuals. It concludes that the inclusion of these phenomena within the discipline of economics necessitates a new approach to a number of areas such as economic planning, taxation and the distribution of wealth as well as a redefinition of the object of study of economics to include all productive activities not just those sanctioned by law and undertaken in the context of markets.
Does Unemployment Lead to Crime?
Authors: Timbrell Martin
Published: January 2017

This papers considers the postulated link between crime and unemployment. It outlines the main theoretical premises for such a relationship and critically summarises the empirical work to date before introducing the specific approach used in the analysis reported here. This is essentially a cross section econometric analysis of crime rates which concludes that unemployment per se has no direct influence on the level of crime. There is evidence that previous studies which reported such a connection were erroneous and that these errors resulted from a confusion between unemployment and the more general concept of economic welfare. Further analysis reveals that there is no evidence that crime is higher among ethnic minorities or in non-rural communities, nor unfortunately that increased policing actually reduces crime.
Constructive Empiricism: a Reconstruction of Economic Methodology
Authors: Boylan Thomas A. , O’Gorman Pascal F.
Published: January 2017

The principal aim of this paper is to explore the possibility of applying van Fraassen’s constructive empiricism to the contemporary debate on the methodology of economics. The authors argue that constructive empiricism supplies a novel and challenging framework which takes this debate beyond relativism and rhetoric on the one hand and beyond instrumentalism and realism on the other. In particular, by developing the distinction between pure and applied economics and by locating economic explanation in the latter, constructive empiricism offers a challenging solution to the perennial question of the realism of assumptions debate, changes the methodological focal point of pure economics onto the issue of empirical adequacy.
Book review: Competition in Theory and Practice
Authors: Meyer F.V.
Published: January 2017

Competition in Theory and Practice, Revised and Updated by Terry Burke, Angela Genn-Bash and Brian Haines. Published by Routledge, 1991. ISBN 0-415-05292-0.

The Nature of the Transnational Firm, Edited by Christos N. Pitelis & Roger Sugden. Published by Routledge, 1990. ISBN 0-415-05271-8 (hbk) and 0-415-05748-5 (pbk).
Book review: The World Trading System at Risk
Authors: Meyer F.V.
Published: January 2017

The World Trading System at Risk, Jagdish Bhagwati, published by Harvester Wheatsheaf, 1991. ISBN 0-7450-1026-1. £10.95. 156pp.
John Stuart Mill’s Wages Fund Recantation: A Lakatosian Analysis
Authors: Vint John
Published: January 2017

There has been a number of attempts to interpret John Stuart Mill’s recantation from the Wages Fund doctrine in 1869. This article attempts to analyze the recantation using a framework which takes account of the development and decline of the wages fund doctrine as a whole. The framework is based on the work of Imre Lakatos and the article aims to rationally reconstruct the history of Mill’s recantation. It is argued that while external events were responsible for focusing attention on trades union matters in the 1860s Mill’s recantation and the aftermath can be accounted for in terms of theoretical weaknesses with the doctrine and its failure to make theoretical progress.
Book review: A Handbook of Economic Sociology
Authors: Mulberg Jon
Published: January 2017

Smelser Neil, J. and Swedberg, Richard, A Handbook of Economic Sociology, Princeton: Princeton University Press 1994, 864 pp. 21 figs. 27 tables 7 x 10. ISBN 0-691-03448-6 Cloth £65/ $99. Distributed by John Wiley & Sons.
Market Failure, Government Failure, Leadership and Public Policy
Authors: Dollery Brian E. , Wallis Joe L.
Published: January 2017

The economic rationale for government intervention in a market economy has traditionally been provided by the theory of market failure. This article reviews the market failure paradigm in the light of the more recent literature on government failure. One implication of the theory of government failure is that a contractualist approach to public service reform is the best method of improving public sector productivity. However, we argue that this view overlooks the potentially crucial role of leadership in public agencies and the ways in which transformational leadership can stimulate efficiency. We argue that communitarian conceptions of leadership can be incorporated into conventional economic approaches, and that this can have significant implications for public policy formulation.
George Eliot and Rational Economic Agents
Authors: Caniglia Alan S.
Published: January 2017

Conventional economists analyze human behavior by assuming a “rational economic agent” who is motivated solely by material self interest. This assumption has come to permeate our analyses of economic situations and policies, yet it is clearly limited, simplifying, and not capable of explaining the full range of human behavior. In this essay the writings of George Eliot are discussed as commentaries on this assumption and the implicit deductive methodology underlying it, and as explorations toward the possibility of a broader conceptual framework for analyzing economic issues. The paper argues that Eliot was knowledgeable about economic discourse and was consciously wrestling with the rational agent assumption and possible alternatives in her fictional as well as nonfictional work. Her writings suggest ambivalence toward the deductive/maximizing framework and the search for broader conceptualizations of human behavior.
Book Review: The Economics of Joan Robinson
Authors: Boylan T.A.
Published: January 2017

Maria Christina Marcuzzo, Luigi L. Pasinetti and Allesandro Roncaglia (eds.). The Economics of Joan Robinson London: Routledge 1996. 370 pp. ISBN 0-41513616-4.
A Note on the Asset-Specific Nature of Life Insurance Firms
Authors: Adams Mike
Published: January 2017

The concept of asset specificity is an important feature of the transaction-cost economics literature. This literature predicts that asset specificity – which embraces physical assets, specialist human capital and intangibles such as brands – fosters greater certainty in complicated transactions of long duration. The business of life insurance is a classical example of complex and long-term exchange between the owners and managers of the firm and its customers. This note thus examines the concept of asset specificity and considers its relevance to the life insurance industry. To stimulate further research four hypotheses are put forward.
Unit Trusts in Singapore: Degree of Diversification
Authors: Chong James , Lim Chow Kiat , Chia Ee Toh
Published: January 2017

This study examines the degree of diversification of the funds in Singapore. The R-square statistic was employed as a measure for the degree of diversification. The findings generally indicated that the local funds were not well-diversified. Various explanations are given to account for this low level of diversification, as indicated by a low R-square statistic. This study also addresses some definitional and conceptual issues relating to diversification that affect the propriety of using the R-square statistic as a measure of diversification. More specifically, Markowitz’s Modern Portfolio Theory is introduced to illustrate the difference between naive and efficient diversification.
The Use of Cost-Benefit Analysis to Decide Environmental Policy – a Dead End?
Authors: Westskog Hege
Published: January 2017

In this paper I discuss two questions which the decision maker has to consider before she makes use of the method of cost benefit analysis. First, she has to ask herself if she shares the ethical foundation of environmental cost benefit analysis. If not, could environmental cost benefit analysis be adjusted such that her ethical beliefs are incorporated? Second, if the decision maker shares the ethical foundation of environmental cost-benefit analysis, is this method appropriate when there are individuals in a society that hold other ethical beliefs than those implicitly assumed in an environmental cost-benefit analysis? When discussing these questions I focus on two different perspectives – the deontological and the agency aspect of individual preferences. I argue that the answer to both questions is «no», though the answer to the second question is not as clear as the answer to the first.
Comparative Product Quality Evaluation
Authors: Giannias Dimitrios A.
Published: January 2017

This paper presents a theory that is appropriate for evaluating the quality of differentiated products. The model is used to evaluate the products of the Japanese motorcycle manufacturers.
Adsorption-based approach to determine the size and mass of humic acids molecules
Authors: Tarasevich Yuri I , Tryfonova Maryna Yu , Dolenko Svitlana A , Aksenenko Eugene V
Published: January 2017

The state of sodium humate in aqueous solution and on a solid surface is studied using various methods. It is shown that in aqueous solution at neutral pH and low ionic strength this substance exists in an associated state. The values of molecular mass of the molecules in the preparation studied (Aldrich) are determined to be 1, 3–6 and 15 kDa. A new adsorption-based approach for initial estimation of the molecular mass and size of humic acid molecules is proposed, which can be used instead of any specific sophisticated equipment. The size of the molecules of the studied preparation estimated in this way (in the range of 2.3 to 9.0 nm), agree well with data obtained by chromatographic and electron microscopic measurements, which confirm the reliability of the proposed method.
Methane adsorption on shale under high temperature and high pressure of reservoir condition: Experiments and supercritical adsorption modeling
Authors: Xiong Wei , Zuo Luo , Luo Litao , Hu Zhiming , Cui Yaxing
Published: January 2017

To understand methane adsorption characteristics on shale at high pressures, we conducted experiments of methane adsorption on dry shale up to 50 MPa and at 95.6 ℃, 75.6 ℃, and 40.6 ℃. Results show that the amount of excess adsorption on shale at high pressures is not the same as that at low pressures. The amount of adsorption increases with pressure until a peak value is reached and then declines with further pressure increases. Isosteric heat of adsorption is studied to explain the excess adsorption behavior. In addition, a new supercritical adsorption model was developed based on supercritical adsorption. This new model and Langmuir model were both used to fit the adsorption isotherms data. Langmuir model matched well with experiment data only at low pressures but failed at high pressures. The new model can fit the adsorption isotherms well, indicating that it reflects the characteristics of supercritical methane adsorption on shale at high pressure and temperature.
Theoretical investigation on the adsorption and diffusion of lithium-ion on and between graphene layers with size and defect effects
Authors: Yu Yan-Zi , Guo Jian-Gang , Zhou Li-Jun
Published: January 2017

Adsorption and diffusion of lithium-ion on and between graphene layers are investigated by an analytical model, employing a pairwise potential, which can be approximated by the Lennard–Jones potential to express the interaction between lithium-ion and each carbon atom of graphene. The equilibrium position and binding energy of lithium-ion at three particular adsorption sites (hollow, bridge, and top) are calculated, and the adsorption stability is discussed. The results show that hollow site is the most stable adsorption site, and top site is the most unstable. The adsorption and diffusion of lithium-ion on different sizes of monolayer graphene are investigated and proved to be size and edge dependent. Moreover, lithium-ion would rather diffuse on the surface of graphene than through a hexagonal carbon ring to the other side no matter what the graphene sheet size is. In addition, two kinds of vacancy defects in graphene are considered to study the diffusion of lithium-ion. The vacancy defect can improve energy barrier, and if a vacancy defect is big enough, lithium-ion migrating through the vacancy area from one layer to another is feasible. The possible applications of present study include rechargeable lithium-ion graphene battery and Li storage in carbon material.
The influence of different organic solvents on the size and shape of asphaltene aggregates studied via small-angle X-ray scattering and scanning tunneling microscopy
Authors: Larichev Yu V , Nartova AV , Martyanov ON
Published: January 2017

An influence of various organic compounds on aggregation of asphaltenes separated from Tartar oil was studied by small-angle X-ray scattering and scanning tunneling microscopy methods. The compounds such as cyclohexane, methanol, formic acid, heptane, tetrabutylammonium fluoride, acetonitrile, decane, hexanol-1, furfural, and octene-1, added to the solution of asphaltenes in toluene, were shown to produce a considerable aggregation of asphaltene particles of ∼10–13 nm size and of an oblong ellipsoid shape along the longer axis. Decalin, dimethylformamide, dimethylsulfoxide, nitrobenzene, aniline, cyclohexanol, monoethanolamine, triethanolamine, 1-methylnaphtalene, and dichloroethane cause asphaltene aggregate sizes to decrease essentially. Acetone, glycerin, ethyl acetate, dioxane, benzyl alcohol, oleic acid, limonene, α-pinene, cycloheptatrien, and nitromethane were shown to influence weakly on aggregation/disaggregation processes of asphaltenes. Conceivable reasons of the observed effects are discussed from general physico-chemical properties of the compounds used.
Adsorption of Propene and Propane on Graphitized Carbon. II. Analysis of Single Gas and Mixed Gas Isotherms
Authors: Glanz P. , Körner B. , Findenegg G. H.
Published: January 2017

Adsorption isotherms for propene and propane on Vulcan 3G were obtained at four temperatures between 273 and 313 K and pressures up to 1 bar, using a microbalance technique. The adsorption of the two gases, and of their binary mixtures (reported in Part 1 of this study), is analysed in terms of the two-dimensional Scaled Particle equation. Whereas Henry's Law constants and isosteric enthalpies of adsorption of the two gases are of nearly equal magnitude, the cross-sectional area β/L = πσ2/4 of propane is found to be about 10% larger, and the lateral interaction energy parameter ε more than 20% larger, than the corresponding parameters for propene. The binary adsorption system conforms to the Ideal Adsorbed Solution model by Myers & Prausnitz, and the interaction parameter α12 for unlike molecules (α ∼ επσ2/4) derived from the mixture adsorption data conforms to Berthelot's mixing rule within experimental accuracy.
Adsorption of Hydrocarbons on Air-Reacted Activated Carbons. I. Adsorption Isotherms
Authors: Martín-Martínez J. M. , Linares-Solano A. , Rodríguez-Reinoso F. , López-González J. D.
Published: January 2017

The adsorption of several hydrocarbons (benzene, cyclohexane, n-butane, n-hexane, 2,2-dimethylbutane and isooctane) on a series of carbons resulting from the reaction of an activated carbon prepared from almond shells with air at 623 K is discussed. The results are parallel to those obtained with N2 at 77 K (González-Vilchez et al. 1979) but very different to those of CO2 at 273 and 298 K (Rodríguez-Reinoso et al. 1984). A comparison of three different ways of expressing the adsorption data is used to discuss the possible molecular sieving effect of the carbons towards the hydrocarbons.
Localized Adsorption of N2 on Sublimed Cadmium Bromide and Real Surface Area
Authors: Rivera-Utrilla J. , Lopez-Peinado A.
Published: January 2017

The adsorption-desorption of N2 at 77.5 K on a sublimed sample of cadmium bromide has been studied. The ideal isotherm is applied to experimental data to determine surface area independently of a BET plot. The Frenkel–Halsey–Hill (FHH) plot indicates that there is a localized adsorption of the nitrogen molecules in the monolayer and that at p/p0 ≥ 0.4 the multilayer adsorption proceeds in a normal way. In order to obtain the real surface area of the sample from the BET's Vm a cross-sectional area equal to 0.178 nm2/N2 molecule should be used.
The Two-Stage Air-CO2 Activation in the Preparation of Activated Carbons. II. Characterization by Adsorption from Solution
Authors: Linares-Solano A. , Rodríguez-Reinoso F. , Molina-Sabio M. , López-González J. de D.
Published: January 2017

Olive stones and almond shells have been used as raw materials to prepare activated carbons following three different experimental methods: (a) carbonization in N2 followed by activation in CO2, (b) direct activation in CO2 and (c) treatment in dry air at 573 K followed by activation in CO2. The carbons have been characterized by the adsorption of paranitrophenol, methylene blue, orange II, crystal violet and victoria blue, all in aqueous solution. Methods (a) and (b) yield carbons with very similar adsorptive capacities and carbons prepared by method (c) have larger adsorptive capacities for similar overall yields. On the other hand, carbons from almond shells (more microporous) would be more suitable for adsorption of small solutes and carbons from olive stones (more macroporous and consequently, with larger rate of adsorption) for larger dimension molecules.
Studies on the V2O5-TiO2 System. IV. Oxygen Chemisorption
Authors: Rey L. , Martino R. , Gambaro L. , Thomas H.
Published: January 2017

The chemical adsorption of oxygen on V2O5 and V2O5 -TiO2 over the temperature range 100–450°C and at pressures between 10−2 and 3 Torr has been studied. Assays have been performed using a volumetric method, the isotherms obtained being in accordance with Langmuir's adsorption model.

Isobaric plots at 1.5 Torr of these isotherms exhibit two maxima, at 250 and 400°C, respectively. These maxima have been interpreted in terms of the surface chemisorption of O2− and its diffusion into the bulk solid.

The amount adsorbed at the 250°C maximum depends on the sample composition in the following decreasing adsorption order: VT80, VT50, VT10, VT20 and VT0.

At the 400°C maximum, the same amount of O2 is adsorbed experimentally by all the TiO2-containing samples, this value being quite different from that corresponding to pure V2O5 (VTO). Possible explanations for this observation are based on (i) the relative magnitudes of the V/Ti surface ratios and (ii) the presence of Ti4+ in V2O5 crystals.
Effect of Micropore Filling on Chemisorption by Large Surface Area Materials. Adsorption of O2 and N2O by CuZnO Catalysts
Authors: Aharoni Chaim , Fubini Bice , Giamello Elio
Published: January 2017

In irreversible chemisorption by large surface area catalysts, the partially covered surface takes up additional amounts of adsorbate only if a given threshold pressure is attained. A model is suggested in which micropore filling acts as a precursor state for other gas-solid interactions. The model is applied to the adsorption of oxygen by CuZnO catalysts with various copper contents, and containing particles and interparticle voids of various sizes.
Reversible Adsorption and Diffusion of Molybdenum during Drying of Alumina Spheres Impregnated with Molybdenum Solutions
Authors: Cáceres C.V. , Blanco M.N. , Thomas H.J.
Published: January 2017

The influence of reversible adsorption and diffusion of molybdenum during the drying step on the redistribution of molybdenum which had been previously impregnated on alumina spheres is presented.

Two approximate theoretical models are postulated to interpret this phenomenon. The first assumes that redistribution is due solely to the diffusion of molybdenum in the solution within the pores towards the centre of the pellet, while the other is based on the assumption that solvent evaporation also has an influence on the process, since this leads to a consequent increase of solute in the interior of the pores.

In both models it is assumed that equilibrium between adsorbed molybdenum and that in the solution, as a consequence of reversible adsorption, occurs simultaneously with molybdenum diffusion.

A good fit between the theoretical profiles and the experimental points was observed in all samples dried slowly at room temperature and humidity.
Adsorption of 1,10-Phenanthroline and Quinoline on to Charcoal from Mixed Solutions
Authors: Helmy A.K. , de Bussetti S.G. , Ferreiro E.A.
Published: January 2017

The adsorption of 1,10-phenanthroline and quinoline by charcoal from single aqueous solutions and from mixtures has been studied. Single plateau high affinity adsorption isotherms were obtained for 1,10-phenanthroline in the presence and absence of quinoline, while the isotherm of quinoline exhibited two plateaus in the presence of 1,10-phenanthroline. The area per adsorbate molecule for each substance, as obtained from the data, indicates that both molecules lie flat with their rings in contact with the charcoal surface. This orientation is the same in adsorption from single and mixed solutions except at relatively high quinoline concentrations in the latter case where a decrease in the area per quinoline molecule is observed.
Adsorption of Iodine from Aqueous Solutions on to Activated Carbons: Correlation with Nitrogen Adsorption at 77K
Authors: Fernandez-Colinas J. , Denoyel R. , Rouquerol J.
Published: January 2017

The adsorption of iodine has been examined on a set of four microporous charcoals subjected to increasing activation, and also on a Vulcan carbon black used as a non-porous reference. Analysis of the iodine adsorption isotherms and of the corresponding differential enthalpies of displacement is consistent with the nitrogen adsorption data, provided that the slightly larger size of the iodine molecule is kept in mind. The αs method, which is normally applied to adsorption from the gaseous phase, has been usefully extended to these liquid/solid systems and leads to a reasonable micropore volume. This approach provides a useful alternative, especially in those cases where the adsorbent cannot be subjected to drying.
Nitrogen and Pyridine Adsorption on Chromia-Coated Silica and Alumina Catalysts: Probing the Chromia Dispersity
Authors: Ismail H.M. , Fouad N.E. , Zaki M.I.
Published: January 2017

Nitrogen and pyridine adsorption studies have been undertaken on variously loaded chromia-coated silica and alumina catalysts. The adsorption data obtained were analyzed with the intention of finding out criteria of relevance to the chromia dispersion. The results have been compared with literature data obtained using a more direct means of investigation. Such comparison showed good agreement which indicates a better dispersion of chromia on alumina than on silica surfaces. This has been tentatively attributed to the different populations and chemistries of the surface hydroxy groups of silica and alumina.
Adsorption and Immersion of Benzene in Active Carbons
Authors: Brückner P. , Jung R. , Radeke K.-H. , Thiede E.
Published: January 2017

A classical gravimetric procedure (spring balance) and a simple immersion calorimeter have been used for the investigation of benzene adsorption from the gaseous phase on to nine active carbons at 293.2 K. The Freundlich, Dubinin-Radushkevich and Dubinin-Astakhov equations have been chosen for describing the equilibrium data. Comparison with the integral inmersion heats demonstrates that only the Dubinin-Radushkevich parameters are consistent with thermodynamic principles.
Equilibrium Studies during the Adsorption of Acid Dyestuffs onto Maize Cob
Authors: El-Geundi Mohammad S. , Aly Ibrahim H.
Published: January 2017

The adsorption of acid dyestuffs in solution onto maize cob has been investigated. Equilibrium isotherms have been determined for the adsopriton of Acid Blue 25 (AB 25) and Acid Red 114 (AR 114) onto maize cob. The L-shaped adsorption isotherms suggest that adsorption proceeds through ionic bonding and that the dye molecules are adsorbed in a flatwise manner on the surface of the maize cob particles. The maximum adsorption capacity of the maize cob was found to be 47.7 and 41.4 mg dye per g maize cob for AR 114 and AB 25, respectively.
Adsorption Heat-Flow Microcalorimetry Applied to Coal Surface Properties
Authors: Rossi P.F.
Published: January 2017

An account is given of the various forces involved in the adsorption of gases and vapours at a solid surface. The heat evolved during such processes may be measured by means of a microcalorimeter such as that designed by Calvet, whose description and application is discussed in detail. The use of such a microcalorimeter in studying adsorption at coal surfaces is described where differences in the measured differential heats of adsorption may be attributed either to the residual mineral content of the coal and/or to oxidation by air during its pretreatment.
Adsorption of Tungsten on Alumina from Sodium Tungstate Solutions. Estimation of Equilibrium and Kinetic Parameters
Authors: Pizzio L.R. , Cáceres C.V. , Blanco M.N.
Published: January 2017

The tungsten adsorption isotherm from aqueous solutions of sodium tungstate on to alumina at 20°C has been studied. The isotherm shape was in agreement with that predicted by the classic Langmuir equation. This model was therefore fitted to the experimental data in order to determine the adsorption equilibrium constant and the total concentration of adsorption sites.

Kinetic parameters of adsorption were also determined. To do so, a theoretical model that predicts the tungsten concentration profiles in impregnated thin layers was fitted to the experimental profiles.

The diffuse reflectance spectra of dried samples used for isotherm determination and of thin alumina layers impregnated with tungsten solutions exhibit a band at 215 nm which is accompanied by a shoulder at 250 nm. For samples having a greater tungsten concentration, the shoulder develops and then transforms into a second band. The maximum at the lowest wavelength (first maximum) is assumed to correspond to tungsten in a tetrahedral coordination (monomeric species) while the second maximum is due to distortion in the tetrahedral symmetry caused by strong interactions between the support and the monomeric species.
Adsorption Studies of Europium on Manganese Dioxide from Aqueous Sulphuric Acid and 1-Propanol Mixtures
Authors: Rauf M.A. , Hasany S.M. , Iqbal M.J. , Hussain M.T.
Published: January 2017

The adsorption of europium on to manganese dioxide from binary mixtures of 1-propanol with aqueous sulphuric acid has been studied as a function of the concentration of the aqueous and organic component. The composition of those mixtures from which maximum and minimum adsorption could be obtained has been determined. The influence of cations and anions has also been studied. Chromate, fluoride, citrate, EDTA, CrIII, AlIII, FeIII, PbII and AgI reduce adsorption appreciably in these mixtures. The adsorption of several other metal ions has also been measured under specific conditions to determine the selectivity of manganese dioxide. Europium and some other metal ions can be separated from elements such as mercury, zinc, etc. which show very low adsorption on manganese dioxide from these binary mixtures.
The Adsorption of Europium on to Titanium Oxide from Aqueous Solutions
Authors: Rauf M.A. , Hasany S.M. , Ikram M. , Shamsi A.M.
Published: January 2017

The adsorption of europium on to titanium dioxide from aqueous solution at pH 4 has been studied in relation to the concentration of the adsorbate. The conditions for maximum adsorption were optimized and the effects of added cations, anions and other metal ions studied. The oxide was found to separate europium from TeIV, CoII and MnII in appreciable amounts under the given conditions.
Composition and Nano-Periodic Structure of Compounds Formed by the Reaction of Molybdenum and Tungsten Heteropolyanions with Cationic Surfactants1
Authors: Filippov A.P. , Kovalenko A.S. , Il'in V.G.
Published: January 2017

Keggin heteropolyanions (HPAns) of structure [PMo12O40]3– and [PW12O40]3– have been allowed to react in acidic media at room temperature with some cationic surfactants of the quaternary ammonium or primary amine type to yield meso-structured insoluble salts with the general formulae Am3[PM12O40], Etn3[PM12O40]2, Etn3[PM12O40]2•nEtnCl2 or AmnH7-n[PM11O39]•xH2O, where Am and Etn are, respectively, mono- and di-cationic surfactant species, M is Mo or W and n can vary in the range 0 to ∼3. All of the materials obtained possessed nano-periodic structures whose maximum d100 parameters ranged from 26 Å to 36 Å, exhibiting lamellar, tetragonal, hexagonal or cubic meso structures depending on the synthesis conditions employed and the nature of the surfactant and HPAns used. The values of the highest d100 parameter obtained for the substances prepared were generally in line with the length of the hydrophobic tail in the surfactant molecule but less dependent on the nature of the metal (Mo or W) when the latter was incorporated in a Keggin anion. However, the structure of the materials was considerably influenced by the pH value of the reaction medium and the P/M ratio when transformation of the Keggin anions into lacunary or other anions was possible.
Adsorption Chromatography in the Examination of Heavy Oil Residues — Comparison of Standard Methods
Authors: Voelkel A. , Fall J. , Grześkowiak T.
Published: January 2017

The relative content of aliphatic/aromatic hydrocarbons, polar species and asphaltene fractions determines the utility of asphalts and is the basis for the selection of the oxidation conditions for heavy oil fractions (distillation residues). The use of different separation methods leads to different types of asphalt (heavy residue) compositions. Three different separation methods were studied and the asphalt or heavy residue compositions arising from these methods were compared.