bluuebunny/crossref_metadata_2025 huggingface dataset:
Serum Albumin and Body Weight as Predictors of Postoperative Course in Colorectal Cancer
Authors: Hickman Donn M. , MILLER Rebecca A. , Rombeau John L. , Twomey Patrick L. , Frey Charles F.
Published: January 2017

The influence of preoperative serum albumin and percent ideal body weight on postoperative outcome was examined in 83 patients operated upon for colorectal cancer. Compared to patients with normal preoperative body weight and serum albumin, the following were noted: 1) those with low serum albumins had increased rates of complications (p < 0.02) and deaths (p < 0.02); 2) complications were increased in obese patients (p < 0.02); and 3) those with two nutritional abnormalities had increased rate of complications (p < 0.05) and deaths (p < 0.01). The group at highest risk, those with both low body weight and decreased serum albumin, had a complication rate of over 70% and a mortality rate of 42%.
Chronic Hypocaloric Parenteral Nutrition Containing Glutamine Promotes Hepatic Rather Than Skeletal Muscle or Gut Uptake of Glutamine After Fasting
Authors: Borel Myfanwy J. , Williams Phillip E. , Jabbour Kareem , Flakoll Paul J.
Published: January 2017

Background: The effect of chronic parenteral infusions of either saline (S), dextrose (D), amino acids without glutamine (AA), or amino acids including glutamine dipeptides (AA+GLN) on interorgan movement of glutamine (GLN) and glutamate (GLU) after fasting was examined. Methods: Multicatheterized mongrel dogs were stressed by fasting for 4 days followed by a 4‐day IV infusion of either S (30 mL/h, n = 8), D (8.6 kcal/h, n = 8), isocaloric AA (8.3 g N/d, n = 7), or isocaloric AA+GLN (8.3 g N/d, 6.8 g GLN/d, n = 6). Hepatic and hindlimb blood flows were estimated, and net arterio‐venous balance measurements (μLmol/kg per minute) were made during the last 2 hours of infusion. Results: Arterial blood concentrations of GLU were 47 ± 6, 52 ± 3, 47 ± 5, and 62 ± 8 and of GLN were 587 ± 25, 548 ± 20, 423 ± 22 (p ≤.05 vs S), and 512 ± 59 μmol/L for S, D, AA, and AA+GLN, respectively. Slight GLU uptake and GLN release by the hindlimb were observed in all groups. Gut GLU production was ‐0.31 ± 0.06, ‐0.04 ± 0.07 (p ≤.05 vs S), ‐0.15 ± 0.05, and ‐0.14 ± 0.02 (p ≤.05 vs S), and gut GLN uptake was 0.64 ± 0.38, 1.54 ± 0.25, 0.80 ± 0.16, and 0.85 ± 0.11. Hepatic GLU uptake was 0.16 ± 0.06, 0.09 ± 0.05, 0,23 ± 0.06, and 0.43 ± 0.10 (p ≤.05 vs S). Net hepatic GLN balance was ‐0.06 ± 0.54, ‐0.77 ± 0.17, ‐0.21 ± 0.13, and 1.92 ± 0.39 (p ≤.05 vs S). Conclusions: Neither hindlimb GLU uptake nor GLN release were influenced by nutrient infusion. Parenteral D blunted gut GLU release with no effect on gut GLN uptake. AA did not alter GLN or GLU balances in the organs measured. However, although AA+GLN infusion did not enhance gut GLN uptake, it did alter hepatic metabolism with a threefold increase in GLU uptake and a shift from net GLN equilibrium to GLN utilization. Thus, GLN administered parenterally after fasting was not directed preferentially for use by skeletal muscle or by gut tissues but rather was used extensively by the liver. (Journal of Parenteral and Enteral Nutrition 20:25–30, 1996)
Using Concept Maps for Educational Based Implementation of Assistive Technology: A Culturally Inclusive Model for Supervision in Special Education
Authors: Huer Mary Blake
Published: January 2017

This article addresses three emerging problems in special education: (a) new learning environments with different teaching styles, (b) equity in access to assistive technology (AT), and (c) an on-going infusion of new AT opportunities within special educational environments. Instructions for designing and creating concept maps are presented as a solution to meet the immense needs currently for AT preservice and inservice personnel preparation. Three sets of teacher/learner questionnaires as well as a new Personal Planning Protocol are introduced for integrating collaborative strategies during AT decision-making, and advocating for a culturally-inclusive model for supervision in special education.
Curriculum Development for the Severely Handicapped Student
Authors: Browder Diane M. , Steward Kathy L.
Published: January 2017

The functional or community adaptation approach to curriculum development for the severely handicapped is described using the curriculum characteristics (1) philosophy and research support, (2) content and sequence, and (3) individualization. This curriculum model is further clarified through a wheel design, a complete curriculum example, and guidelines for I.E.P. development.
Interactive Video as a Learning Medium for Mentally Handicapped Adolescents
Authors: Carter Jeri , Browning Philip , Nave Gary , White W.A.T.
Published: January 2017

This study was designed to determine whether (1) different types of informational feedback (i.e., error correction) affected learning performance; and (2) interactive video was an effective instructional medium with mildly handicapped adolescents. Twenty-six Ss were matched in pairs based on a pretest score and age and then randomly assigned to two groups. The respective group mean IQs were 58 and 60. The learning task consisted of responding to a 10-item true/false learning module on budgeting. Each S was taught individually in a single session. Each of the 10 items would reappear in the interactive video instuctional session until S responded to that item correctly two consecutive times or until S erred on the item a total of three times. Items were presented iteratively to minimize simple memorization of correct responses. The results indicated this medium was effective in that significant learning occurred for both groups. However, there were no differences between Ss introduced to the more extended (Group A) versus briefer (Group B) form of informational feedback.
Streamlining Exceptional Student Placement with PERT
Authors: Radencich Marguerite C.
Published: January 2017

This article explains the usefulness of PERT (Program Evaluation and Review Technique) in streamlining the currently cumbersome exceptional student referral process. With PERT, realistic time and personnel needs can be established so that the referral process can be completed within reasonable time limits. In addition, the status of every referral can be known at all times.

A sample work breakdown structure for referrals is developed as the initial step in PERT. With this step, the process is broken down into small manageable units. Based on this, a network is developed. The network shows the interrelationships and priorities of the steps needed to complete the referral process.
Using Computers with Curriculum-Based Monitoring: Effects on Teacher Efficiency and Satisfaction
Authors: Fuchs Lynn S. , Fuchs Douglas , Hamlett Carol L. , Hasselbring Ted S.
Published: January 2017

The purpose of this study was to examine the effects of using computer software to store, graph, and analyze student performance data on teacher efficiency and satisfaction with curriculum-based progress-monitoring procedures. Subjects were 20 special education teachers of mildly and moderately handicapped pupils; teachers were assigned randomly to a computer-assisted or a paper-and-pencil monitoring group Teacher efficiency in using the monitoring procedures was observed twice during a 3-month implementation period. In the first phase, all teachers used paper-and-pencil procedures; in the second, 10 teachers continued to use paper-and-pencil procedures while 10 teachers used computer-assisted monitoring procedures. Teacher satisfaction was assessed once at the completion of the study. Analyses of variance indicated that computer assistance was associated with a decrease in efficiency but an increase in teacher satisfaction. Implications for practice and additional research are discussed.
The Effects of Microcomputers on the Secondary Special Education Classroom Ecology
Authors: Rieth Herbert , Bahr Christine , Polsgrove Lewis , Okolo Cynthia , Eckert Robert
Published: January 2017

This study was designed to investigate the impact of the microcomputer upon the curricular content, curricular format, student behavior, teacher behavior, and teacher focus employed in secondary special education resource room programs. These behaviors were compared in classes in which a microcomputer was used with classes in which no computer was used.

Overall, the data suggested different effects associated with computer use The most important benefits appear to be increased active task engagement and increased individually focused instruction. In many key categories of teacher behavior, however, there were no significant differences between the computer-use and noncomputer-use classes. The data strongly suggest that teachers will need training and support if they are to integrate computers into their instructional programs.
Effects of Video Games as Reinforcers for Computerized Addition Performance
Authors: Axelrod Saul , McGregor Gail , Sherman Judith , Hamlet Carolynn
Published: January 2017

This study examined the effects of video games as reinforcers for computer-assisted math performance Four students were presented with addition problems on a computer for 15 minutes daily. Using a multielement design, all students were exposed to two variable ratio (VR 10 and VR 5) and a No-Games reinforcement condition. Neither schedule of reinforcement increased student accuracy or had a substantial effect on the rate of correct responses. In the No-Games reinforcement condition, students had more opportunities to respond and a greater number of correct answers. The authors suggest that programmers of educational software incorporate reinforcement procedures that consume minimal amounts of computer time to maximize instructional efficiency.
Using Computers to Generate IEPs: Rethinking the Process
Authors: Smith Stephen W. , Kortering Larry J.
Published: January 2017

Computer-assisted Individualized Education Programs (IEPs) offer the promise of enhancing special education practice. For instance, such technology could enhance the IEPs participatory process by empowering parents and students, ease the bureaucratic demands of timely standardized documents, improve upon the overall quality of the document, and facilitate more effective instruction. For all the promises, however, we must consider the possibility that this technology may reinforce existing flaws or, perhaps, create new ones. We see technology as reshaping the IEP process; a reshaping we hope is in the best interest of special education and the students we serve. Accordingly, we examine the IEPs evolution, the organizational influences on the adaptation of technology, and legal and programmatic issues. We also delineate questions and offer recommendations for the future use of technology to help develop IEPs.
Helping Behavior, Dispositional Empathic Concern, and the Principle of Care
Authors: Wilhelm Mark Ottoni , Bekkers René
Published: January 2017

This research investigates the relative strength of two correlates of helping behavior: dispositional empathic concern and a moral principle to care about others. The empathy–helping and care–helping relationships are investigated using data from the General Social Survey, a nationally representative random sample of the U.S. adult population. Ten helping behaviors are investigated. The results show that the care–helping relationship is stronger than the empathy–helping relationship for most helping behaviors, and that the empathy–helping relationship is mediated by the principle of care. That dispositional empathic concern is mediated by the principle of care requires new theoretical interpretations of the empathy–helping relationship, and suggests new directions for research on helping behavior.
Les Consequences Politiques Du Vote Feminin
Authors: Dogan Mattei
Published: January 2017

Le vote des femmes a eu des conséquences décisives sur les résultats électoraux, bouleversant et même annihilant la volonté électorale des hommes, à certains moments, dans dix des seize démocraties européennes. L'analyse est entreprise en termes de valeur marginale, qui est l'cffet cumulatif de l'écart électoral entre les sexes et du décalage numérique entre la Gauche et la Droite. Dans l'hypothèse théorique d'un suffrage exclusivement masculin l'histoire électorale et parlementaire de la France, de l'Angleterre, de l'Allemagne et de l'Italie aurait été très différente.
Present Prospects for Women's Political Participation in Italy
Authors: Caddeo Maria Letizia , Vianello Mino
Published: January 2017

After the war, Italy passed through a notable but uneven period of economic development. The great changes in the economic structure of the country were not accompanied by policies directed toward changing the traditional style of life and of the family, where the women had the function of caring for and satisfying the various needs of the members of the family. The lack of social services and infrastructures is consequently a strong brake on women's opportunities to get out of the house and enter the working world. Therefore, notwithstanding legislation aimed at equality, women in Italy are few with regard to work, almost absent from public life, and above all absent from professional, political, and governing élites.
Women's Political Participation and the 1980 Crisis in Poland
Authors: Siemieŉska Renata
Published: January 2017

Problems besetting the Polish society in the post-war period (massive migration, reconstruction of the country after war-time destruction, industrialization involving high social costs, sluggish growth of living standards, recurring strains and political crises) united society more than divided it along sex lines. High legal equality and fast industrialization combined with widespread occupational mobilization of women, without, howover, ensuring their real equality, resulted in the emergence in some socio-occupational groups of attitudes that at times (especially recently) are quite different than demands for women's greater social and political activity.
Patriarchy: The Last Universal
Authors: Edwards John N. , Kluck Patricia
Published: January 2017

UNIVERSAL patriarchy, asserting that males are always dominant, is firmly established as part of our conventional and scientific wisdom. Close examination of this contention shows it, however, to be wanting on both conceptual and methodological grounds. Further suspicion as to its truth claim derives from an inspection of a dubious case, that the Dahomey of Africa, in whose society women equally occupied positions of authority with men in all major institutional sectors of society. Coupled with these conceptual, methodological, and empirical difficulties, the evolutionary scenario—man as hunter—commonly used to support the notion of universal patriarchy is found to be more of a political convenience than an adequate explanation of dominance patterns. Taken together, these considerations strongly indicate the implausibility of sustaining universal male dominance as a scientific generalization. Some of the implications for family studies of its continued acceptance are noted.
Child Maltreatment: An Analysis of Familial and Institutional Predictors
Authors: Ory Marcia G. , Earp Jo Anne L.
Published: January 2017

THE purpose of this paper is to identify familial and institutional predictors of child maltreatment. Interrelationships between timing of first childbearing, presence of social disorganization within the family, the availability of family and institutional supports, and the incidence of child maltreatment are examined for fifty maltreating and fifty nonmaltreating families drawn from social service case histories in rural North Carolina. While child maltreatment was not associated with early parenting or lack of potential family social support, a strong relationship was found between the likelihood of child maltreatment and the family's degree of social disorganization and their amount of social service utilization. The study unvariables explained 59% of the variance in child maltreatment. A log linear analysis was performed to determine the interactive influence of the two most important predictors of child maltreatment: level of social disorganization and social service utilization. Recommendations for the identification and treatment of families at high risk are suggested.
Divorce in Worcester County, Massachusetts, 1863-1880
Authors: Mulligan William H.
Published: January 2017

THE historical study of divorce practice has only recent begun and has not yet addressed the increasing frequency of divorce Using Worcester County, Massachusetts as a test case, this article examines the late nineteenth century when, while divorce was still rare, the increase was beginning. Through analysis of the socioeconomic characteristics of those obtaining divorces, this article presents a preliminary hypothesis that explains the increasing frequency of divorce in terms of basic changes of American life, particularly the increased economic independence of women brought about by industrialization.
Impact of Adoption of Yoga Way of Life on the Reduction of Job Burnout of Managers
Authors: Adhia Hasmukh , Nagendra H R , Mahadevan B
Published: January 2017

Burnout is a prolonged response to chronic emotional and interpersonal stressors on the job, and is defined by the three dimensions of exhaustion, cynicism, and inefficacy. Job burn-out is a debilitating psychological condition, which has serious repercussions for an individual's personal health as also on the organizational effectiveness. The past 25 years of research has established the complexity of the construct, and has placed the individual stress experience within a larger organizational context of people�s relation to their work. As a holistic science concerned with all aspects of human functioning, yogic science provides a unifying framework by which stress can be understood and eliminated. Yoga involves a systematic method by which we can begin to expand our awareness of the processes which lead to stress and thus gain control over them.

Yoga way of life has direct relevance to address the issue of stress and burnout. While several studies in the past have acknowledged this aspect and discussed various ways by which Yoga can address this aspect, till date very little effort has gone into empirically assessing the impact of Yoga way of life. The main contribution of this paper is to fill this gap. This study hypothesizes that managers who learn and adopt the Yoga way of life will be able to reduce their job burnout better than the others who engage in other things to improve their physical and mental progress. An experiment was conducted to collect data and test the hypothesis in a manufacturing unit.

The results show that adoption of the Yoga way of life can significantly reduce the job burnout of managers. The Yoga way of life is an integrated approach to the changing physical, mental, vital and emotional personality of an individual. It is aimed at making managers more evolved individuals with better understanding of their job situation in the overall context of life. Through a rigorous literature review and understanding of the science of Yoga as given in our scriptures, the paper also provides an explanation of the mechanism of how this happens. Among many suggested coping skills for stress, yoga happens to be fitting in the best, mainly because of its ability to change positively the individual responses to stress stimuli. However, in order to get benefit of Yoga in its entirety, one has to adopt Yoga as a technique of life management. The authors motivate the HR managers in organizations to explore ways of implementing the Yoga way of life as it promises to address the issue of stress at a fundamental level.
Developing a Comprehensive Financial Inclusion Index
Authors: Ambarkhane Dilip , Shekhar Singh Ardhendu , Venkataramani Bhama
Published: January 2017

In spite of efforts of six and half decades, poverty reduction in the country is not in sight. Rightly therefore, the 11th and 12th Five-Year Plans focus on inclusive growth. In order to compare the performance of different states or regions, a comprehensive measure of financial inclusion is necessary which takes into account all its aspects. Review of literature on the subject reveals that measures so far suggested take into account only the supply side. This article suggests a measure taking into consideration supply, demand and infrastructure dimensions. It also takes into account the factors such as population growth, law and order situation and corruption, which have adverse impact on the factors which lead to financial inclusion. These adversely impacting factors are termed as drag.

Separate indices are developed for three dimensions, namely, supply, demand and infrastructure, and a composite index of these three dimensions is computed. Also an index of drag factors is calculated. A comprehensive financial inclusion index is arrived at by modifying the former index by giving the effect of impact of drag.

The index developed is comprehensive as well as flexible, in the sense that new parameters can be added to any of the dimensions including the drag, depending upon identification of parameter and availability of data. It is most suited to Indian conditions and can be used to measure comparative performance of Indian states or sub-regions of the states. It is also applicable to developing countries in general.

The composite index is developed by using displaced ideal method which satisfies intuitive criteria of development index, namely, normality, anonymity, monotonicity, proximity, uniformity and signalling, collectively referred to with the acronym NAMPUS.
Role of Workplace Spirituality in Relationship between Organizational Culture and Effectiveness
Authors: Vallabh Priyanka , Vallabh Gourav
Published: January 2017

The article tries to explore the role of workplace spirituality in relationship between organizational culture and organizational effectiveness. Denison’s theory of organizational culture and effectiveness is used for articulation of the above relationship. Denison’s framework focuses on four cultural traits: involvement, consistency, adaptability and mission. These traits collectively facilitate an organization’s capabilities for integrating and coordinating internal resources as well as its adaptation of the external environment, thereby leading to organizational effectiveness. All these cultural traits and their relationship with spirituality and organizational effectiveness are discussed in the article. This article is an attempt to emphasize that organizational culture should give a place for spiritual expression.
Currency Boards in Theory and Practice: The Case of Argentina
Authors: Cooper John C.B.
Published: January 2017

Central banks in a number of countries have become engines of inflation through their money creating powers. To obviate this, some countries such as Argentina have adopted a currency board as an alternative form of monetary authority. This paper explains the mechanics of a currency board vis à vis a central bank and examines how the Argentinian economy has progressed from the establishment of its quasi-currency board in 1991 until March 2001.
Excitation of Low-Frequency Rotational Vibration
Authors: Schlaak Hans-Joachim
Published: January 2017

Special exciters are necessary to calibrate angular accelerometers, angular velocimeters and rotational angle transducers. This paper presents methods designed for the generation of low-frequency uniaxial rotational quantities. The operating principle, the construction and the technical characteristics of the rotational exciters are described. The air-borne rotational exciters (prototypes) allow sinusoidal angular vibrations in the frequency range from 0.5 to 1000 Hz to be generated. Another mode of operation is the excitation of sinusoidal vibrations by the rotation of the moving exciter part at constant angular velocity (up to 1500 rpm). Further operating modes are the excitation of acceleration shocks and other arbitrary rotational movements of interest for the dynamic investigation of rotation transducers.
Infrasonic Radiation Properties of an Axial Blower
Authors: Qibai Huang , Zhiyun Xu
Published: January 2017

The relationship between the directivity of infrasound emitted by an axial blower, rotational speeds of the impeller, blade type, thickness of blade trail edge, and infrasonic noise radiated by the blower is studied through experiments. Therefore, the infrasonic radiation law is revealed. Furthermore, a theoretical basis for infrasonic control of the axial blower is provided.
Modelling of a Flexible Robot Manipulator Using Finite Element Methods: A Symbolic Approach
Authors: Tokhi M. O. , Mohamed Z. , Hashim A. W. I.
Published: January 2017

This paper presents the development of a symbolic approach in characterising the dynamic behaviour of flexible robot manipulators using finite element (FE) methods. A constrained planar single link flexible manipulator is considered. A simulation algorithm of the system is developed using a symbolic language which enables system characterisation with varying parameters. Analyses and investigations in terms of system transfer function, stability, response and end-point vibration to an input command arc presented. An assessment of the performance of the approach is presented and discussed through numerical simulations.
Comparison of Nitrogen Adsorption and Mercury Penetration Results
Authors: Adkins Bruce D. , Davis Burtron H.
Published: January 2017

Mercury penetration pore volumes obtained for four materials (two silicas, alumina and zirconia) agreed closely with the “Gurvitsch Volume” obtained from nitrogen adsorption. The pore volume of the materials used in this study was found in a narrow range of pore sizes that are amenable to both mercury penetration and nitrogen adsorption measurements. The average crystallite sizes calculated from the BET surface area and from TEM measurements agreed closely except for the highest surface area (310 m2/g) material. The surface areas obtained from mercury penetration or the BET method agree closely for the two lower area materials but the mercury penetration is much higher than the nitrogen surface area for the two higher area materials.
Isothermal Dynamics of the Adsorption of Multicomponent Mixtures
Authors: Filippov L.K.
Published: January 2017

Theoretical models for the isothermal dynamics of the adsorption of multicomponent mixtures have been classified. The conditions determining a given frontal behaviour have been shown to depend on the type of theoretical model employed, on the kind of the adsorption isotherm and on the values of the mass exchange parameters inside and outside the porous grains in the porous medium. It has been shown that S type models of the kinetics of interphase mass exchange occurring within porous grains are of limited applicability, whereas the C type appears to be more sensible. Formulae for calculating the quantities determining the frontal behaviour for multicomponent mixture adsorption have been derived.
Thermal Desorption of N-Nonane from Different Porous Solids
Authors: Guerrero-Ruiz A. , Grillet Y.
Published: January 2017

The adsorption capacity and adsorption kinetics of n-nonane on two carbons and four zeolites have been determined in order to obtain information about the microporous structures present in these solids. In addition thermal desorption of n-nonane has been studied by the Constant Rate Thermal Analysis method. It is observed that hydrocarbon diffusion through pores is the parameter which controls the desorption process. N-nonane adsorption into the micropores of the solids is not a ready process which sometimes exhibits slow adsorption kinetics because of the inaccessibility of the molecules to narrower micropores.
Adsorption Studies of Arsenic on Manganese Dioxide Using Radiometric Techniques
Authors: Rauf M.A. , Hasany S.M. , Ikram M. , Najam-ud-Din M.
Published: January 2017

Manganese dioxide has been tested as an adsorbent for the removal of arsenic using radiometric techniques. Optimum conditions for maximum adsorption in terms of equilibrium time, nature and composition of electrolytes, shaking time, effect of foreign ions and other metal ions have been investigated. On the basis of these data, high separation factor values were obtained in the case of CoII, HfIV and TeIV. The adsorption data were also found to obey the Freundlich equation, the mean sorption energy of As on MnO2 being 15.5 kJ/mol.
Effect of Na2O Doping on the Surface and Catalytic Properties of the Mn2O3/Al2O3 System
Authors: El-Shobaky G.A. , Ghozza A.M. , Hammad S.
Published: January 2017

Manganese/aluminium mixed oxide solids having the formula 0.2MnCO3/Al2O3 were prepared by mechanical mixing of a known weight of finely powdered manganese carbonate and aluminium hydroxide. The solids obtained were treated with NaNO3 (0.75–6 mol%) solution and dried at 110°C, then calcined in air at 500°C and 800°C for 6 h. The phases produced were identified by XRD analysis. The surface properties (SBET, Vp and r̄) of the pure and doped solids were studied by using N2 adsorption at – 196°C and their catalytic activities were determined by studying the oxidation of CO by O2at 125–300°C.

The results obtained reveal that pure and doped mixed solids preheated in air at 500°C and 800°C consist of Mn2O3 (partridgite) and a poorly crystalline γ-alumina. Doping with sodium oxide at 500°C and 800°C resulted in a small decrease (14–19%) in the SBET value of the treated solids. However, this treatment brought about a significant modification in the catalytic activity of the doped solids. Doping with 0.75% Na2O at 500°C led to an increase of about 30–50% in the specific catalytic activity which was found to decrease on increasing the percentage of Na2O above this limit, falling to values smaller than that measured for the undoped catalyst. Doping at 800°C led to a progressive decrease in the activity of the treated solid to an extent proportional to the amount of dopant present. The doping process at 500°C and 800°C did not modify the mechanism of the catalytic reaction but altered the number of catalytically-active sites contributing in the catalysis of CO oxidation by O2 without changing their energetic nature.
Studies on the Influence of Temperature on the Adsorption of Some Cationic Surfactants on to Steel
Authors: Al-Lohedan H.A. , Khamis E. , Issa Z.A.
Published: January 2017

The inhibition of steel corrosion by cationic surfactants has been investigated in acidic media. The study demonstrates a correlation between the inhibition action towards corrosion and increasing numbers of methylene groups per surfactant molecule. The mode of adsorption of inhibitor molecules on the steel surface in H2SO4 solutions containing different concentrations of cetyltrimethylammonium bromide (CTABr), n-tetradecyl- N,N,N-trimethylammonium bromide (TDTABr), n-dodecyl-trimethylammonium bromide (DDTABr) and n-decyltrimethylammonium bromide (DTABr) has been investigated. Measurements have been conducted at temperatures ranging from 10°C to 50°C for all surfactants studied. The activation parameters Ea and ΔS, and the thermodynamic parameters ΔG0ads., ΔH0ads. and ΔS0ads., have been determined and their values discussed. The Temkin adsorption isotherm and a recent kinetic–thermodynamic model fit the process of surfactant adsorption on to a steel surface well. The binding constant, the free energy of adsorption, the lateral interaction and the number of active sites are reported.
Study of Adsorption from Dilute Aqueous Solutions on to Activated Carbon. Part 1. Novel Representation of Experimental Data
Authors: Mészáros R. , Nagy M. , Veress G.
Published: January 2017

The dependence of the equilibrium concentration of dilute aqueous solutions of 1-propanol and 2-propanol on the mass of adsorbent for two types of activated carbon was investigated at fixed initial concentrations. Two kinds of differential equation were proposed for the characterization of these curves. The solution functions of the given differential equations were fitted to the experimental data. The second model was accepted as providing a good description of the required functional relationship. The similarity and differences in the values of the constants relative to the functions arising from the accepted model were also discussed for the two types of activated carbons.
Adsorption of Cationic Surfactants on Rutile
Authors: Vanjara Ajay K. , Dixit Sharad G.
Published: January 2017

The adsorption and zeta potential of two series of cationic surfactants, i.e. alkyltrimethylammonium bromide and alkylpyridinium chloride, on rutile have been studied. The two series varied only in their hydrocarbon chain length. The effect of chain length on the lateral two-dimensional aggregation phenomena of surfactant molecules on the rutile surface has been explained by evaluating various thermodynamic parameters such as the effective number of CH2 groups removed from the aqueous environment on to the solid surface (dn/d In C), the mean cohesive energy per CH2 group (Φ) and the average mean aggregation number of the hemimicelle (nhm). The value of the mean cohesive energy in the case of alkyltrimethylammonium bromide (0.599 kcal/mol) is in very good agreement with literature values. It supports hemimicellar formation.
Structure, Texture and Catalytic Properties of Pd/SiO2 Catalysts
Authors: El-Hakam S.A. , Ahmed Awad I. , Hassan S.M. , Farage H.M.
Published: January 2017

The structural properties of Pd/silica catalysts have been investigated by means of DTA and X-ray techniques. The X-ray results indicate that Pd metal is the only phase formed. The textural properties were determined using low-temperature nitrogen adsorption. Surface areas were calculated and the dependence of the surface area on the metal content has been discussed. Pore structure analyses indicate the presence of both micro-and meso-pores. The dehydrogenation of cyclohexane was found to be affected by the metal content. The active site for the dehydrogenation process on Pd/silica catalysts consists of one Pd atom. The kinetics of the dehydrogenation exhibit a fractional order.
Dehydrogenation of Cyclohexane in Relation to Some Textural and Catalytic Properties of Ni/Al2O3 and Co/Al2O3 Catalysts
Authors: El-Nabarawy Th.
Published: January 2017

Ni/Al2O3 and Co/Al2O3 catalysts of different compositions have been prepared. Their structural properties were determined using X-ray diffraction and differential thermal analysis. The textural properties of these catalysts were determined from nitrogen adsorption at 77 K. The catalysts were reduced with hydrogen at 673 K and the adsorption of hydrogen on the reduced catalysts was measured at 320 K. Dehydrogenation of cyclohexane at flow rates of 10–30 ml/min and at 633–723 K was investigated.

The loading of alumina with metal oxides leads to changes in the textural properties depending on the degree of loading and on the loaded metal oxide. The adsorption of hydrogen allowed the determination of important catalytic parameters. Dehydrogenation of cyclohexane on the investigated catalysts followed fraction order kinetics. The dehydrogenation activity has been related to the H2 uptake and to the extent of metal dispersion on the support.
Adsorption Characteristics of Coal-based Activated Carbons. II. Adsorption of Water Vapour, Pyridine and Benzene
Authors: El-Nabarawy Th. , Petro N.Sh. , Abdel-Aziz S.
Published: January 2017

Chemically-activated carbons were prepared by carbonizing Maghara coal with different amounts of phosphoric acid at 873 K. Steam-activated carbons of different burn-off were prepared by gasifying non-activated carbon prepared by carbonization at 873 K with steam at 1173 K. Samples of steam-activated carbons were also treated with concentrated nitric acid or with potassium dichromate. The adsorption of water vapour and benzene was determined at 308 K. The adsorption of pyridine was followed on the chemically-activated carbons at 343 K.

The adsorption of water vapour was found to be related to the surface area and the amount of carbon–oxygen groups. Some of the adsorbed water was found to be specifically held to the surface and could be used to determine the number of carbon–oxygen groups on the surface. Two mechanisms are involved in the adsorption of pyridine on the carbons investigated. These are physisorption on the oxygen-free surface and chemisorption on carbon–oxygen groups of an acidic nature. Benzene may be vertically oriented in micropores, horizontally oriented in wider pores and may be even inaccessible to the fraction of the surface located in ultramicropores. Benzene adsorption is also retarded by the existence of a high concentration of carbon–oxygen groups oh the surface.
Activated Carbons Tailored to Remove Different Pollutants from Gas Streams and from Solution
Authors: El-Nabarawy Th. , Mostafa M.R. , Youssef A.M.
Published: January 2017

Non-activated carbon ‘A’, physically-activated carbons P1–P4, zinc chloride-activated carbons Z1–Z4 and potassium sulphide-activated carbons K1–K4 were prepared from Maghara coal (Sinai, Egypt). The surface areas of these carbons were determined by investigating the adsorption of carbon dioxide at 298 K and of nitrogen at 77 K. The decolourization powers of the carbons were determined from methylene blue adsorption at 308 K. The adsorption of methanol, benzene, n-hexane, n-octane and α-pinene at 308 K was also determined using equilibrium and flow techniques. The removal of ammonia and phenol from water was investigated on some selected samples. The activated carbons showed high capacities towards the removal of organic pollutants from water and from gas streams via adsorption. Their capacity towards a particular pollutant depends on the method of activation and is related to the textural and/or the chemistry of the carbon surface.
Treatment of Activated Carbon with H2O2. Effect on the Porous Texture
Authors: Gómez-Serrano V. , Acedo-Ramos M. , López-Peinado A.J. , Valenzuela-Calahorro C.
Published: January 2017

The effect of the oxidation of activated carbon (AC) with aqueous solutions of H2O2 on the porous texture of the material has been investigated. In such treatments of AC, H2O2 solutions of varying concentration and pH (i.e., unchanged pH and pH values of 2.5 and 11.5) were used. Oxidizing solutions containing Fe2+, Fe3+, ethanol or ether were also employed. Initial outgassing of AC and contact of the intermediate product with the oxidizing solution were effected under controlled conditions of temperature and time. The resulting samples were characterized texturally by gas adsorption (N2, 77 K) and mercury porosimetry. The mass of sample significantly increased when H2O2 solutions at pH 2.5 were used. Such treatment of AC produced a loss of microporosity or none depending on the method of preparation of the samples. Thus, a loss of microporosity occurred, for example, when contact between the H2O2 solution and the AC was effected at 0°C, whereas no loss of microporosity occurred when the temperature was 70°C. For a few samples the unfavourable effect of oxidation of the AC on its porous texture not only concerned the micropores but also the mesopores and macropores.
Surface, Acidic and Catalytic Properties of Silica—Alumina Catalysts in Relation to Their Chemical Composition
Authors: El-Nabarawy Th. , Khalil L.B. , Hamada M.A. , Nawar N.
Published: January 2017

Silica–alumina catalysts of varying chemical compositions were prepared under controlled conditions, employing the coprecipitation technique. The surface properties were determined from the adsorption of nitrogen at 77 K. The acidity was investigated by determining the adsorption of pyridine at 423 K and by following its thermal desorption up to 773 K. The conversion of 2-propanol at 523 K and the cracking of cumene at 693 K were investigated using the pulse microcatalytic technique.

The surface area decreased and the mean pore volume increased with increasing alumina content. The amount of acid present and its surface density increased while the relative acid strength decreased with an increase in the alumina content. The extent of dehydration of 2-propanol increased with increasing surface acid density and proved to be insensitive to the acid strength. The cracking of cumene appears to depend on the surface area, the amount of acid present and the acid strength of the catalyst, although its dependence on these parameters is of a relative complex nature.
Adsorption Properties of Silica with Chemically Bonded Amino and Guanidino Groups
Authors: Roshchina T.M. , Davydov V.Ya. , Khrustaleva N.M. , Mandrugin A.A. , Gurevich K.B.
Published: January 2017

The influence of the non-homogeneity of the silica support and the nature and amount of modifier employed on the adsorption properties of materials with chemically bonded amino and guanidino groups was studied by means of gas chromatography (GC), adsorption measurements under static conditions and IR spectroscopy. The results indicate that adsorbents coated with a polymer film of amino groups have a nearly uniform surface. These adsorbents can be used for GC investigations and for the separation of polar compounds, including organic bases.
Adaptation of Single Gas Adsorption Equations for the Description of Adsorption from Non-aqueous Liquid Solutions of Iodine on to Active Carbons
Authors: Ziólkowska D. , Garbacz J.K.
Published: January 2017

The solution analogs of four single gas adsorption equations have been formulated. The derived expressions have been applied for the description of the experimental adsorption isotherms from binary liquid solutions with limited component miscibility on to microporous active carbons, as well as for the derivation of standard chemical affinity distribution functions.
Physicochemical and Technological Aspects of the Hydrothermal Modification of Complex Sorbents and Catalysts. Part I. Modification of Porous and Crystalline Structures
Authors: Leboda R. , Charmas B. , Sidorchuk V.V.
Published: January 2017

This paper deals with the hydrothermal modification of the physicochemical properties of complex mineral sorbents and catalysts. The hydrothermal modification of alumina, magnesia, ferric oxide and zirconia/silica hydro- and xero-gels as well as other complex adsorbents obtained by the coprecipitation and mechanical stirring of suitable components is discussed.

The paper deals with the following topics: (a) the physicochemical bases of the hydrothermal method; (b) methodological and technological problems of the hydrothermal treatment of adsorbents; (c) hydrothermal modification of porous structure parameters (specific surface area, pore volume and size); and (d) characteristics of the hydrothermal modification of the porous structure of multicomponent adsorbents and catalysts.

In addition, the mechanism of the hydrothermal modification of the porous structure of composite materials is discussed.
Physicochemical and Technological Aspects of the Hydrothermal Modification of Complex Sorbents and Catalysts. Part II. Modification of Phase Composition and Mechanical Properties
Authors: Leboda R. , Charmas B. , Sidorchuk V.V.
Published: January 2017

Two main ways of applying the method of solid hydrothermal treatment have been considered: (a) hydrothermal modification of polycrystalline adsorbents and catalysts; and (b) hydrothermal synthesis of materials possessing regular porosity (zeolite-like, laminar and others). Modification processes of phase composition and mechanical properties of complex adsorbents and catalysts were discussed. The essential features of hydrothermal crystallization in multicomponent systems have been presented.
Surface and Catalytic Properties of SnO2–Cr2O3 Catalysts
Authors: El-Sharkawy E.A. , Mostafa M.R. , Youssef A.M.
Published: January 2017

Co-precipitated SnO2–Cr2O3 catalysts of different chemical composition were prepared. The textural properties were determined from the low-temperature nitrogen adsorption isotherms while the structural properties were determined using FT-IR spectroscopic techniques. The magnetic moments of the catalysts were measured by the Gouy method. Catalytic conversion of 2-propanol, 1-butanol and the dehydrogenation of cyclohexane were followed using the pulse microcatalytic technique.

No spinel structure was detected, even upon calcination at temperatures as high as 973 K. Only Cr2O3 was detected for samples containing ≥15 mol% chromia. The chemical composition and calcination temperatures are important factors in determining the textural properties of mixed oxide catalysts. The catalytic activity depends on the effective magnetic moment and surface acidity.
Development of Porosity in Bone Char during Decolourization of Sugar Syrup
Authors: Girgis Badie S. , Kader Aida Abdel , Aly Abdel Nasser H.
Published: January 2017

Fresh service bone char was subjected to four column decolourization cycles composed of use for 4 d and re-activation. The adsorption of N2 by the used and regenerated chars, and the adsorption of methylene blue and iodine by the activated chars, was determined. Specific surface areas of ca. 90 m2/g were recorded up to the end of the third cycle, which then decreased thereafter with appreciable pore widening. Pore size distributions for the fresh and activated char indicated two peaks corresponding to micropores (13–15 Å) and mesopores (35–40 Å). Subsequent to the end of decolourization, the second peak diminished due to deposition of the adsorbed colouring matter inside the mesopores. After regeneration, the mesopores appear again. Use of the Freundlich and Langmuir equations allowed the adsorption data for methylene blue to be linearized properly. The monolayer capacity of the dye appears to be independent of the age of the char. Iodine numbers were generally comparable to the BET surface areas as measured by nitrogen adsorption.
Desulphurization of Um Al Nar Refinery Straight-Run Kerosene and Gas Oil Using Palm Fruit Kernel Activated Charcoal: A Locally-Made Adsorbent
Authors: Radwan Gamil M.H. , Nassar Mamdouh M.
Published: January 2017

Desulphurization of Um Al Nar Refinery straight-run kerosene and gas oil has been investigated using adsorption techniques. Palm fruit kernel activated charcoal (PFKAC), a locally-made adsorbent, has been used for the adsorption of sulphur compounds in batch tests over a range of initial sulphur concentrations at 25°C and adsorbent particle size ≤ 75 μm. The results revealed the potential of PFKAC as a low-cost adsorbent. PFKAC showed a higher capacity for sulphur at gas oil concentrations than in the case of kerosene. The experimental isothermal data were correlated to the Freundlich model. Values of the Freundlich exponent, n, were > 1 indicating that sulphur compounds are favourably adsorbed on PFKAC. The Langmuir model also fitted the experimental data. A correlation has been developed for fitting the experimental data and has been found to be reasonably good.
Compaction versus Surface Parameters of Certain Solid Catalysts
Authors: Amin Anwar , Ali Laila I. , Ibrahim Anwar M.
Published: January 2017

The effect of compaction at 0.31–3.1 t/cm2 on Al(OH)3, Mg(OH)2 and their mixed hydroxide was studied by nitrogen adsorption. With Al(OH)3, compaction gave no significant changes up to 1.24 t/cm2, but above 1.55 t/cm2 a considerable decrease in SBET and an increase in pore radius occurred with small changes in pore volume. This could be ascribed to the presence of free water between the structural layers in the material which normally prevents their contact and a consequent destruction of the pore structure. With Mg(OH)2, compaction at low pressures decreased SBET and increased the pore dimensions as a result of adhesion between neighbouring particles, leading to a blocking of that fraction of the micropore structure originally accessible to nitrogen molecules. Increasing compaction led to a marked increase in the adsorption capacity as a consequence of plastic deformation associated with the breakage of fragile primary particles and the creation of new surfaces. Compaction of the mixed hydroxide led at first to an increase in both the SBET and Vp values (due to fragmentation of the particles), followed by a loss of SBET due to the presence of a mixture of particles in the system which increase the compression ability of the latter. Complete pore structure analysis showed that samples of Al(OH)3 powder when compacted at 0.31 and 1.55 t/cm2 were microporous. All other samples contained mainly mesopores.