bluuebunny/crossref_metadata_2025 huggingface dataset:
Recherche interdisciplinaire et réflexion sur l’interdisciplinarité
Authors: Laflamme Simon
Published: September 2012

L’interdisciplinarité constitue une pratique scientifique usuelle et féconde. Il y a d’ailleurs de nombreuses théories interdisciplinaires. Mais il n’y a pas de théorie de l’interdisciplinarité. Les études sur l’interdisciplinarité parlent d’une approche appelée à sauver le monde, dichotomisent monodisciplinarité et interdisciplinarité, fabriquent des typologies du travail interdisciplinaire, mais elles ne livrent pas de théories de l’interdisciplinarité. En fait, le projet d’une telle théorie est absurde parce que s’il peut y avoir des théories scientifiques, il ne peut y avoir de théorie de la science. C’est ce que soutient cet article.
Une nouvelle logique de l’interdisciplinarité
Authors: Schmid Anne-Françoise , Mambrini-Doudet Muriel , Hatchuel Armand
Published: September 2012

Une épistémologie non-standard, relativement autonome des disciplines et du présent, est nécessaire pour caractériser une nouvelle logique de l’interdisciplinarité. Il s’agira de montrer comment la crise de la représentation des sciences, la modification des objets scientifiques contemporains, l’hétérogénéité et l’incompatibilité des modèles – un autre rapport au futur dans les sciences – nous conduit à pratiquer une « interdiscipline » qui ne peut plus être caractérisée comme la combinaison de connaissances disciplinaires différentes. Nous montrerons comment construire dans cette hétérogénéité des « lieux d’interdiscipline » qui permettent de nouvelles relations entre les disciplines, ainsi que des relations démocratiques entre disciplines. Cela suppose une translation ou une dérive des disciplines et une conception des objets comme « inconnus » et non représentables dans une « distance phénoménologique ».
La double quête : un essai sur la dimension cosmologique de synthèses interdisciplinaires en sciences sociales
Authors: Stoczkowski Wiktor
Published: September 2012

Depuis leur émergence, les sciences sociales se livrent à une double quête : d’une part, elles cherchent à construire une connaissance objective du monde humain; d’autre part, elles souhaitent employer cette connaissance pour apporter au monde humain des améliorations radicales. Ces deux ambitions ont été systématiquement tenues pour complémentaires et compatibles : la connaissance de l’homme et de la société devait être un moyen; la transformation de l’homme et de la société en était la fin. Il s’agit là d’un pari fondateur des sciences sociales, responsable de la plupart des espoirs dont on a pu les investir. En prenant comme exemple quatre « grandes théories », cet article se propose d’analyser les présupposés et les implications de cette double quête des sciences sociales.
De l’interdisciplinarité à l’inter-épistémê. Le cas d’une formation interdisciplinaire de troisième cycle en gérontologie
Authors: Belzile Louise , Couturier Yves , Lorrain Dominique
Published: September 2012

L’article porte sur la représentation des premiers diplômés et doctorants d’un programme de formation doctorale en gérontologie sur la place de la composante interdisciplinaire dans leur cursus. Celle-ci est représentée comme une source d’enrichissement personnel et professionnel pour les étudiants, essentielle à la compréhension en profondeur des phénomènes complexes qui émergent du vieillissement et à la constitution d’une perspective gérontologique. La condition fondamentale favorable à cet effet semble être la constitution dans le cadre des séminaires d’un espace inter-épistémologique de formation qui a su se prolonger dans l’ensemble des activités du lieu de formation.
Automated Class Scheduling System
Authors: Gamale Jeralyn M. , Anuta Edward C. , Sayson Zina D.
Published: September 2012

The study tested the functionality of Automated Class Scheduling System in terms of speed, data handling, accuracy, security, stability and adaptability in making class schedules. This study was conducted in Bohol Island State University Main Campus, Tagbilaran City during the second semester of school year 2010-2011. The respondents of this study were the 6 expert instructors in the field of computer programming. They tested and evaluated the functionality of the program in terms of its design, accuracy, data handling, security, stability and adaptability. Another 8 instructors who are in charge of making class schedules determined the functionality of the system in terms of speed, accuracy, data handling, stability and adaptability of the software. Separate set of questionnaires were given to two groups of respondents. The study concluded that the manual and the automated class scheduling systems are both functional. However, the automated system is more functional because of its extra features which solve the primary problems in creating class schedules.
Students' Beliefs toward Mathematics as Related to Their Performance in College Algebra
Authors: Garcia Gary C.
Published: September 2012

The study was to determine the beliefs of SLSU-San Juan BSED freshmen towards mathematics and their performance in college algebra. Data gathered were analyzed and interpreted using Weighted Mean, Percentages, Pearson r, and the Point Biserial coefficient of correlation. Findings showed that students' educational background is 62% and 38% from public and private respectively. Majority (66%) strongly agreed that mathematics is a challenging subject and 34% considered the latter as one of the difficult subjects. Relationship between beliefs about mathematics and performance in college algebra is statistically significant at 0.05. Relationship between students' educational background and performance in college algebra was found to be not significant. The study proved that male students have better performance in college algebra than female. Students with positive beliefs about mathematics performed better in the subject. Educational background of the students was not a determinant for having good performance in college algebra. Considering the result of the study, teaching development program focusing on giving the importance of belief in teaching college algebra was recommended. Thus, values formation towards mathematics will be integrated in lesson planning to build positive beliefs.
Psycholinguistic Extracts and Socio-Cultural Imprints in Job Application Discourses: A Genre Analysis
Authors: Songcuan Emmanuel J.
Published: September 2012

Genres represent purposive and staged ways of communicating in a culture and enacting a range of important institutional practices. Genre studies have paved the way for understanding the way discourse is used in academic, professional, and institutional contexts. This paper analyzed the psycholinguistic realization and drew out socio-cultural imprints in the construction of application letter and resume in the Philippine setting. Qualitative and quantitative methods were employed in the analysis of job application documents representing different professions to determine the generic structure and the linguistic features of the moves and strategies that accomplish the communicative functions of the genres. Employers' group survey and job interview extracts were also used to cross-validate and provide snapshots on the interpretations made. A seven-move and a five-move generic structure occurring in a flexible sequence define the composition of job application letter and resume, respectively. The construction of these two types of discourse is influenced and constrained by the applicant's psycholinguistic repertoire, professional background, and socio-cultural milieu. A genre-based pedagogy is recommended to sensitize Filipinos of the existing genres and textlinguistic variations in the workplace.
Competencies in the Workplace of the Bachelor of Science in Fisheries Graduates of the Western Philippines University
Authors: Montano Elsa Carmen N. , Salvador Nelson S.
Published: September 2012

This study was conducted to assess the Bachelor of Science in Fisheries' graduates competencies and how they fare in their job as assessed by the employers. The study employed the descriptive survey and correlational methods of inquiry using a prepared questionnaire that involved 46 graduates. The data gathered were statistically treated and analyzed with the use of frequency, percentages, mean, ranking, weighted mean, Chi-square and Cramer's coefficient. Results revealed that most of the graduates were employed in the government agencies. The graduates' competencies were indicative that they can work with others. Employers confirmed the graduates are capable and very prepared for work. A Significant association existed between the graduates' nature and status of employment in terms of present employment status, place of work and employing skills and their professional preparation as to reasons for taking the course. The employers' assessment of the graduates in terms of their job performance, quality of graduates being employed, employment skills and other skills were significantly associated to the graduates reasons for taking the course. The study concluded that graduates nature and status of employment are the results of their professional preparation.
Academic Reading Proficiency of Freshmen in the College of Education of DMMMSU-SLUC: Input to the Design of Instructional Modules for English 101
Authors: Uychoco Dionisio M.
Published: September 2012

The study described the academic reading proficiency level of incoming college freshmen which served as an input to the design of learning modules. It used a validated 50-item researchermade test and two sets of questionnaires to determine the adequacy of learning activities and the extent of utilization of academic reading strategies by content area teachers. The research found the studentrespondents unprepared for college work given the moderate academic reading proficiency index. Concerned language and content area teachers failed to provide enough learning activities and sufficient opportunity and training in the use of academic reading strategies that will enhance students' level of proficiency in content area reading. It is recommended that topics designed to develop academic reading skills of senior high school students be included in the course content in secondary schools; that English teachers provide more learning activities and experiences expected in content area reading; and that content area teachers become active reading teachers by facilitating comprehension through the use of time-tested academic reading strategies.
The Study of Effect Meta Theoretical Curricula's Implementation in Educational Performances of Tehran Universities in Educational Science
Authors: Sarmadi Mohammad Reza , Pour Hassan Shahraki , Elhamian Negar
Published: September 2012

This research program to study the application performance Meta theory Education Faculty of Educational Sciences at the University of Tehran in the year 89-88 has been done. The aim of this study is to examine that faculty of Educational Science, the curriculum specialists and executives, to what extent the common teaching of basic and fundamental vision benefit and which has higher priority. The research in this study is a descriptive survey approach. Measuring the validity and reliability of the questionnaire with 30 questions in 4 Meta theories Miller, Eisner, Hunecke, Walker and Questionnaire in the five-choice Likert scale was determined. Was appointed and Based on simple random sampling method and survey a sample of 87 people and then run the data analysis software SPSS 17. Descriptive statistics were used in the indicator of central tendency. In order to determine the relationship between variables in inferential statistics, k- square method was used. Also the Friedman test analysis was used to determine priorities. The results of the survey questions suggest that Merit-oriented elements in the Miller Performance Training Meta theory Faculty of Educational Sciences at the University of Tehran to other applications. This means that goals in education are used more tangible, more visible and more specific cognitive characteristics.
Learning for Jobs: Flexibile Learning in Vocational Education and Training
Authors: Petnuchova Jana , Hrmo Roman
Published: September 2012

The article describes importance of vocational education and training (VET) which can play a central role in preparing young people for work, developing the skills of adults and responding to the labour market needs of the economy. The aim of this article is to highlight the definitions and understandings of vocational education and training (VET). Countries are now giving the long-neglected topic of vocational education and training dramatically increased profiles, reflecting recognition of its economic function. The aim of this article is to highlight the definitions and understandings of vocational education and training (VET). Personal philosophy of learning is based on a personÂ´s own fundamental values. It should provide answers to the following questions: Why should I study continuously? Where will success leads to and who will be beneficiaries? Will it be enough if I benefit from process myself or do I want to help other people to succeed?
Modular Instruction in Biology: It’s Effect on Students’ Performance
Authors: Bedaure Archel A.
Published: September 2012

This investigation ascertained the effect of modular instruction on the performance in Biology of freshmen fishery students at the Carlos Hilado Memorial State College (CHMSC) - College of Fisheries during the second semester of the school year 2009-2010. Experimental research using the pre - test, post - test control group design was employed to achieve the objectives of the study. Participants were grouped into the experimental and the control groups. The experimental group was exposed to modular instruction while the control group was exposed to lecture-discussion approach. The pre-test performances of both experimental and control groups were fair. The post-test performance of the experimental group taught by modular instruction was superior while that of the control group taught by lecture-discussion was very good. A significant difference was found between the pre - test of the modular and lecture-discussion groups in favor of the latter group. A significant difference was found between the post - test results of the control group in favor of the experimental group. Significant differences were found between the pre - tests and post -tests of the experimental and control groups hence, modular instruction was better than the lecture -discussion approach in effecting students' performance in Biology.
Effectiveness of Problem-Based Learning Approach to the Students' Problem Solving Performance
Authors: Tupas Sylvino V.
Published: September 2012

The Philippines' ranking in Trends in International Mathematics and Science Survey (TIMSS) is indicative of how mathematics is taught in the classrooms. This descriptive research determined the performance of 12 BSMT and 17 BSMarE freshmen students in solving general mathematics problems. They were preselected cadets who enrolled in a Maritime School in the Philippines first semester school year 2009-2010. Two sets of test instruments of similar context and style were used as pretest and posttest. The selected problems included routine or nonroutine and multistep problem and within the context and level of the students. Result shows a significant improvement in the performance of both BSMT and BSMarE students and as a whole at 0.05 alpha. Further, students developed various heuristics which includes Guess and Test, Working Backwards, Act it Out, Use of Diagram, Use of Algebra, Direct Counting, and Systematic List. Significant performance of students in the posttest is an indicator of the effectiveness of the problem-based learning (PBL) approach. Exposing them to various routine and non-routine problems enable students to apply mathematical concepts and understanding into real life problem situations. This makes mathematics more relevant which enhanced studentsâ€™ interest and level of performance in mathematics.
Students' Opinion on the Faculty Performance Evaluation Instrument
Authors: Sy Francis Ann R. , Felisilda Violeta B.
Published: September 2012

Students' feedback on faculty performance is an influential measure in obtaining the objectives of teaching effectiveness. Southern Leyte State University-Tomas Oppus usually experiences student evaluation reactions on faculty performance. Considering that success of the evaluation process is the instrument itself, this research dealt with students' degree program profile and academic performance; determined their opinion on the criteria's appropriateness and the instrument's validity, reliability, objectivity, and utility and their attitude upon it; and, determined relationship between academic performance and degree program on opinions of the four criteria. Through the descriptive one shot survey, stratified sampling was employed to college freshmen, juniors and seniors with different courses of SY 2010-2011. The mean, percentage, frequency, and chisquare were used. The students' opinion on the appropriateness of the criteria was very appropriate and very high on the four criteria. They manifested positive attitude on the instrument. Their academic performance and degree program have no significant relationship with their opinion on the instrument. Student's opinion of the evaluation instrument was very appropriate, yet, it has to be revisited because some items, though minimal, were moderately appropriate.
Description of a complete Liopropoma larva from the Gulf of California (Mexico) and its comparison with L. fasciatum and L. longilepis (Actinopterygii: Epinephelidae)
Authors: Feeney RF , Lavenberg RJ , Pitman RL
Published: September 2012

A postflexion 18.5-mm Liopropoma larva, with entire dorsal fin filaments, was dip-netted at night at the surface in the Gulf of California (Mexico). The second and third dorsal spine filaments were both unusually elongate. The second spine was about ten times the body length, with twelve heavily pigmented swellings or vanes connected by a soft, flexible filamentous section that tends to coil, resembling the siphosome of a siphonophore. Morphometrics of the larva were similar to adult L. fasciatum, especially the head length, snout length, interorbital width, length of the caudal peduncle, and pelvic spine length. The depth of the caudal peduncle was similar to L. longilepis. The fresh specimen had orange chromatophores over most of the body. After preservation, melanophores were present only over the cranium, tip of the lower jaw, the eye, and in the elongated dorsal filaments. Other described Liopropoma larvae are compared and discussed.
The Human Gene Mutation Database (HGMD) and Its Exploitation in the Fields of Personalized Genomics and Molecular Evolution
Authors: Stenson Peter D. , Ball Edward V. , Mort Matthew , Phillips Andrew D. , Shaw Katy , Cooper David N.
Published: September 2012

The Human Gene Mutation Database (HGMD) constitutes a comprehensive core collection of data on germ‐line mutations in nuclear genes underlying or associated with human inherited disease (http://www.hgmd.org). Data cataloged include single‐base‐pair substitutions in coding, regulatory, and splicing‐relevant regions, micro‐deletions and micro‐insertions, indels, and triplet repeat expansions, as well as gross gene deletions, insertions, duplications, and complex rearrangements. Each mutation is entered into HGMD only once, in order to avoid confusion between recurrent and identical‐by‐descent lesions. By March 2012, the database contained in excess of 123,600 different lesions (HGMD Professional release 2012.1) detected in 4,514 different nuclear genes, with new entries currently accumulating at a rate in excess of 10,000 per annum. ∼6,000 of these entries constitute disease‐associated and functional polymorphisms. HGMD also includes cDNA reference sequences for more than 98% of the listed genes. Curr. Protoc. Bioinform. 39:1.13.1‐1.13.20. © 2012 by John Wiley & Sons, Inc.
Metallomics Using Inductively Coupled Plasma Mass Spectrometry
Authors: Vaccaro Brian J. , Menon Angeli L. , Lancaster W. Andrew , Adams Michael W. W.
Published: September 2012

Inductively Coupled Plasma Mass Spectrometry (ICP‐MS) is a highly sensitive elemental analysis technique that has been widely applied in many fields. Here we describe applications using a broad‐scale approach to examine metal usage in biology. These protocols address questions such as: Which elements from the surrounding environment are taken up into the cells of a given organism? How does this vary between different organisms? Which metals are “bound” and which are “free”? With which type(s) of proteins are the “bound” metals associated? This allows for investigations into several branches of bioinorganic chemistry including uptake, toxicity, detoxification, bioremediation, and the discovery of new uses for elements. In the protocols presented here, there is an emphasis on metals, and, more narrowly, on transition metals because these comprise the majority of tightly protein‐bound, low‐abundance elements. Nonmetals, metalloids, main‐group metals, and f‐block metals are also analyzed and investigated. The sample preparation procedure requires acid lability for detection, which likely eliminates certain nonmetals, such as selenium. However, one advantage of the protocols described is that they are readily adapted to measure any element of interest. Curr. Protoc. Chem. Biol. 4:249‐274 © 2012 by John Wiley & Sons, Inc.
Effects of Addition Order of the Components on Polyamide‐6/Organoclay/Elastomer Ternary Nanocomposites
Authors: Isik‐gulsac Isil , Yilmazer Ulku , Bayram Goknur
Published: September 2012

The effects of addition order of the components for ethylene–glycidyl methacrylate (E‐GMA) copolymers and two types of organoclays (Cloisite® 15A and Cloisite® 30B) on morphology and mechanical properties of polyamide‐6/elastomer/organoclay ternary nanocomposites were investigated by x‐ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) analyses, melt flow index (MFI) measurements, differential scanning calorimetry (DSC), and tensile and impact tests. Four different addition orders (All‐S, PI‐C, PC‐I, and IC‐P) were applied through melt blending in a twin‐screw extruder. All‐S indicates that the elastomer, the organoclay, and polyamide‐6 were compounded in the extruder simultaneously, and the resulting compound was extruded once more. The other symbols represent the components for the two extrusions. P, I, and C stand for polyamide‐6, elastomer, and organoclay, respectively. The first two ingredients were compounded in the first extrusion, and the resulting compound was mixed with the third component in the second extrusion run. For polyamide‐6/ Cloisite® 15A/E‐GMA nanocomposites processed by PI‐C and IC‐P addition orders, stacked silicate layers were observed in the TEM micrographs. On the contrary, the nanocomposites with Cloisite® 30B gave the best result in terms of intercalation/exfoliation in the IC‐P sequence. Generally, for Cloisite® 15A containing ternary nanocomposites, the All‐S addition order gave the highest impact strength, tensile strength, and Young's modulus owing to potential interactions between the functional groups of the three components. For polyamide‐6/Cloisite® 30B/E‐GMA ternary nanocomposites, the PC‐I mixing sequence produced the highest Young's modulus. For these nanocomposites, impact and tensile strengths and elongation at break were relatively insensitive to the mixing order. © 2012 Wiley Periodicals, Inc. Adv Polym Techn 32: E675–E691, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21310
Bubble size and radial gas hold‐up distributions in a slurry bubble column using ultrafast electron beam X‐ray tomography
Authors: Rabha Swapna , Schubert Markus , Wagner Michael , Lucas Dirk , Hampel Uwe
Published: September 2012

Gas hold‐up and bubble size distribution in a slurry bubble column (SBC) were measured using the advanced noninvasive ultrafast electron beam X‐ray tomography technique. Experiments have been performed in a cylindrical column (DT = 0.07 m) with air and water as the gas and liquid phase and spherical glass particles (dP = 100 μm) as solids. The effects of solid concentration (0 ≤ Cs ≤ 0.36) and superficial gas velocity (0.02 ≤ UG ≤ 0.05 m/s) on the flow structure, radial gas hold‐up profile and approximate bubble size distribution at different column heights in a SBC were studied. Bubble coalescence regime was observed with addition of solid particles; however, at higher solid concentrations, larger bubble slugs were found to break‐up. The approximate bubble size distribution and radial gas hold‐up was found to be dependent on UG and Cs. The average bubble diameter calculated from the approximate bubble size distribution was increasing with increase of UG. The average gas hold‐up was calculated as a function of UG and agrees satisfactorily with previously published findings. The average gas hold‐up was also predicted as a function of Cs and agrees well for low Cs and disagrees for high Cs with findings of previous literature. © 2012 American Institute of Chemical Engineers AIChE J, 59: 1709–1722, 2013
Synthesis of Chiral N‐(Purin‐6‐yl)amino Acid Derivatives by using Natural Amino Acids as Starting Materials
Authors: Niu Hong‐Ying , Bai Shi‐Xia , Wu Shan , Qu Gui‐Rong , Guo Hai‐Ming
Published: September 2012

An efficient synthetic method for the preparation of N‐(purin‐6‐yl)amino acids and their derivatives from readily available natural amino acids under mild reaction conditions has been developed. A one‐pot reaction within a short reaction time gives high yields of the chiral N‐(purin‐6‐yl)amino acid derivatives with an easy post‐reaction procedure, which is promising for large‐scale production.
N‐Alkylsulfonylimines as Dipolarophiles in Cycloaddition Reactions
Authors: Stubbing Louise A. , Savage G. Paul , Brimble Margaret A.
Published: September 2012

First described in the late 1960s, N‐alkylsulfonylimines are heterocumulenes that participate in reactions with a range of 1,3‐dipoles to afford interesting 3‐, 4‐, 5‐, and 6‐membered heterocycles. The distribution of adducts obtained suggests that multistage, stepwise mechanistic pathways rather than a concerted process are in operation.
Electron Spin Resonance Study of Radicals Derived from Picolines
Authors: Rakowsky TH. , Dohrmann J. K.
Published: September 2012

ESR spectra of the three isomeric 1‐hydropicolinyl radicals (methyl‐substituted 1‐hydropyridinyl radicals) have been measured in solution at room temperature. The radicals have been generated by in situ photoreduction of the picolines in isopropyl alcohol solution containing acetone. Most of the coupling constants could be assigned experimentally. Calculations of π spin density using the Hückel, McLachlan, and INDO approximations have been performed for the 1‐hydropicolinyls and also for 1‐hydropyridinyl. Two of the ring proton coupling constants of both 1‐hydro‐2‐methylpyridinyl and 1‐hydro‐3‐methylpyridinyl and the signs of all the proton coupling constants have been assigned on the basis of calculated McLachlan spin densities. The Q parameters of the McConnell‐type relations have been deduced from the measured coupling constants of the 1‐hydropicolinyls and of 1‐hydropyridinyl by use of the condition for conservation of spin density. The values obtained are Q = −27.7 ± 1.1 G, Q = −14.5 ± 2.6 G, and QH = 26.2 ± 1.1 G. It could be shown that only the signs of the spin density calculated by the McLachlan procedure resulted in consistent values of Q. The Karplus‐Fraenkel relation for the nitrogen coupling constant has been confirmed. The values of the Q parameters have been deduced from measured coupling constants and experimental spin densities. Values of QN = 9.6 ± 2.5 G and Q = 8.5 ± 2.9 G have been found. Comparison of the Q parameters with values previously determined for related radicals indicates that there are differences between the groups of 1‐hydropyridinyl and N,N′‐dihydrodiazine radicals.
Nahordnungen in Flüssigkeiten, III1H‐ und13C‐NMR‐spektroskopische Untersuchungen zum Solvatationsverhalten von Acrylnitril und seinen Methylderivaten
Authors: Schröer W. , Lippert E.
Published: September 2012

Die Konzentrationsabhängigkeit der1H‐ und13C‐NMR‐Lösungsmittelverschiebung der Vinylgruppe von Acrylnitril und den methylsubstituierten Derivaten wird im binären System mit CCl4und im ternären mit CCl4/HMPT (Hexamethyl‐Phosphorsäure‐Triamid) untersucht und nach dem Modell der Kontaktwahrscheinlichkeiten [1, 2] ausgewertet. Für die Wechselwirkung der basischen Phosphoryl‐Gruppe mit dem β‐trans‐Proton wird für Acrylnitril eine Kontaktenergie von ΔH= (−2,5 ± 0,15) kcal/mol erhalten. Die Wechselwirkung mit dem α‐Zentrum ist geringer, während am β‐cis‐Proton keine wesentlich über die statistische Wahrscheinlichkeit hinausgehende Kontaktwahrscheinlichkeit beobachtet wird. Durch den +I‐Effekt der Methylgruppe sind die Wechselwirkungen mit den methylsubstituierten Verbindungen, insbesondere beim Methacrylnitril, geringer. Größe und Richtung der Assoziatverschiebung werden durch das Zusammenwirken der elektrostatischen Polarisation der CH‐Bindungen und der magnetischen Anisotropie in der Nachbarschaft der solvatisierenden PO‐ bzw. CN‐Gruppen erklärt.
Das Reaktionsverhalten von Bromacetylen I. Die Reaktion von H‐Atomen mit Bromacetylen
Authors: Lange W. , Wagner H. Gg. , Zetzsch C.
Published: September 2012

Die Reaktion von Wasserstoffatomen mit Bromacetylen wurde im Temperaturbereich zwischen 252–345 K und bei Drücken von 3–9 Torr in einem isothermen Strömungssystem untersucht, das an ein Massenspektrometer mit Molekularstrahleinlaß angeschlossen war.

Die Temperaturabhängigkeit der Geschwindigkeitskonstante für den Elementarschritt

läßt sich durch den Arrheniusausdruck

beschreiben.

Eine deutliche Druckabhängigkeit der Geschwindigkeitskonstante konnte nicht beobachtet werden.
Optisch‐elektronische Temperaturmessung an Plasmaflammen mit einer Xenon‐Hochdruck‐Lampe als Vergleichsstrahler
Authors: Huster R.
Published: September 2012

Es wird gezeigt, wie unter Verwendung einer Xenon‐Hochdruck‐Lampe als Vergleichsstrahler Plasmatemperaturen bis 5000 K mit einem objektiven, kontinuierlich arbeitenden Verfahren gemessen werden können. Im Zusammenhang hiermit wird eine Methode entwickelt, regelbare Vergleichsstrahler mit Hilfe nur eines Temperatur‐Fixpunktes absolut zu eichen.
Gitterschwingungsspektren — XII. Mitteilung [1] IR‐, FIR‐ und Ramanspektren von Erdalkalimetall‐ und Bleihalogenat‐Monohydraten
Authors: Lutz H. D. , Klüppel H.‐J.
Published: September 2012

Die IR‐Absorptionsspektren, ‐Reflexionsspektren und Ramanspektren der Erdalkalimetall‐ und Bleihalogenat‐Monohydrate: Ba(ClO3)2 · H2O, Pb(ClO3)2 · H2O, Ca(BrO3)2 · H2O, Sr(BrO3)2 · H2O, Ba(BrO3)2 · H2O, Pb(BrO3)2 · H2O und Ba(JO3)2 · H2O sowie der deuterierten und partiell deuterierten Verbindungen werden im Bereich von 4000 — 30 cm−1 bei Temperaturen zwischen ‐160 und +190°C analysiert. Die Zuordnung der Schwingungen zu den verschiedenen Rassen der Faktorgruppe erfolgte mit Hilfe von Einkristallmessungen. Durch die starke Kopplung der inneren Schwingungen der Halogenationen wird eine relativ große Faktorgruppenaufspaltung der Schwingungen hervorgerufen. In den Halogenaten des Ba(ClO3)2 · H2O‐Typs liegen, wie aus der Lage der OH‐Streckschwingungen (bzw. den OH‐Valenzkraftkonstanten) sowie aus der anomalen Temperaturabhängigkeit der inneren Schwingungen der H2O‐Moleküle hervorgeht, symmetrische, jedoch nichtlineare Wasserstoffbrücken zu den Halogenationen vor, deren Stärke vom Chlorat zum Jodat zunimmt. Die Wasserstoffbrücken des Ca(BrO3)2 · H2O sind dagegen, wie das Auftreten von je zwei OH‐ und OD‐Streckschwingungen des HDO in teildeuterierten Präparaten zeigt, stark asymmetrisch.
Surface Potentials of Kr and Xe on Mo, Ni and Ti Surfaces
Authors: Müller Jaroslav
Published: September 2012

The surface potentials (SP) of Kr and Xe on Mo, Ni and Ti films deposited at room temperature have been determined by a capacitor method. We were interested to follow the SP not only during the submonolayer and monolayer adsorptions but also during the formation of multilayers. The SP data for Kr show characteristic features at a monolayer stage assessed independently by the BET and the point B methods. Monolayer capacity values assessed by different criteria are compared for Kr adsorption on Mo and Ni, and are shown to be in good agreement. A new criterion for the monolayer completion is suggested which is based on the time dependent effect very clearly observed with Kr as an adsorbate. There is evidence for the rearrangement of the adsorbate layer at or around the monolayer and during multilayer formation. With Xe as an adsorbate there is a substantial difference between the monolayer capacity estimates based on the SP data on one side and the estimates based on the BET or the point B methods on the other side. The CTNB and the polarization approaches are discussed from the point of view or !heir ability to predict the SP on polycrystalline as well as the single crystal surfaces. The problems connected with the SP isotherms are discussed in connection with the monolayer capacity determinations from the SP data.
Studien zum Vorgang der Wasserstoffübertragung 35 [1] Aufklärung des Verlaufs der elektrochemischen Reduktion von Diarylsulfonen zu Arylsulfinsäuren mit Hilfe polarographischer und voltammetrischer Messungen
Authors: Horner Leopold , Meyer Erich
Published: September 2012

Polarographische und voltammetrische Daten zeigen, daß Diarylsulfone an der Quecksilberkathode in Gegenwart von Tetraalkylammoniumsalzen im protischen Medium nach einem ECE‐ und aprotischen Medium in Abhängigkeit von Art, Zahl und Stellung der Substituenten am Phenylring und vom Spannungsvorschub nach einem EEC‐Mechanismus zu Sulfinsäuren abgebaut werden.

Substituenten am Phenylrest beeinflussen je nach Art und Stellung die Reduktionspotentiale. Dieser Zusammenhang wird an Hand der Hammett‐Beziehung diskutiert.
Massenspektrometrische Untersuchungen über Erzeugung und Reaktionen von C2H‐Radikalen
Authors: Lange W. , Gg. Wagner H.
Published: September 2012

Bei der massenspektrometrischen Analyse der im Plasma von Mikrowellenentladungen in Bromacetylen‐Helium‐Gemischen gebildeten Teilchen konnten u. a. die Radikale C, C2 und C2H nachgewiesen und deren Konzentrationsabfall nach Verlassen der Entladungszone in Abhängigkeit von der Reaktionszeit verfolgt werden.

Durch Einstellung geeigneter Entladungsstärken ließen sich maximale Konzentrationen bestimmter Teilchen erzeugen: so konnten bei geringer Entladungsenergie relativ hohe C2H‐Konzentrationen dargestellt werden. Von dieser Tatsache wurde zur Untersuchung der Reaktionen des C2H‐Radikals mit H2, O2 und C2H2 Gebrauch gemacht.
Primary Processes in the Photolysis of NO2
Authors: Gaedtke H. , Troe J.
Published: September 2012

The quantum yield of the photolysis of NO2 (6 Torr) under continuous irradiation has been measured in the presence of N2 in the pressure range 0 ≤ P(N2) ≤ 1000 atm at temperatures 296 ≤ T ≤ 428 K and wavelengths 313 ≤ λ ≤ 416 nm. The primary quantum yield is separated from the contribution of secondary reactions. The dependence of the primary quantum yield on pressure, temperature and wavelength is analyzed in terms of the specific rate constants k(E) for photolysis and detailed rate constants for collisonal energy transfer.
Complete Theory of Paramagnetism in Transition Metal Ions IV. The d2 and d8 Electron Configurations in Cubic (Oh and Td), Tetragonal (D4h), and Trigonal (D3d) Symmetry
Authors: König E. , Kremer S.
Published: September 2012

On the basis of the diagonalization of the complete Coulomb repulsion, ligand field, spin‐orbit interaction, and Zeeman effect matrices, the magnetic properties were calculated for the octahedral and tetrahedral d2 and d8 electron systems. In addition, the corresponding tetragonally and trigonally distorted systems were likewise studied. Irreducible tensor operator (Racah) methods were used in both weakfield and intermediate‐field coupling, and complete agreement of the results was achieved. The magnetization was evaluated by direct numerical differentiation of the energies, followed by Boltzmann averaging, and no assumptions limiting the applicability to high temperatures and small magnetic fields were introduced.

Plots are presented giving the effective magnetic moment μeff as function of the ligand field parameter 10 Dq in Oh and Td symmetry for a fixed set of values of B, C, ζ, and k. In D4h and D3d symmetry, similar plots are furnished which present μeff as function of the parameter Dt or D. Here 10Dq as well as K = Ds/Dt = Dσ/Dτ assume fixed values. The H‐dependence of μeff is found to be minor. The effect of a variation in the parameter values B, C, ζ, and k is likewise studied. The results may be employed in an accurate comparison of experimental magnetic and spectroscopic data with theory.
Excited State Properties of Aromatic Thioketones: Thiofluorenone
Authors: Serafimov Ognian , Brühlmann Ueli , Huber J. Robert
Published: September 2012

The absorption and emission properties of thiofluorenone (TF, C2v molecular symmetry) were investigated in 3‐methylpentane at 77 K. By comparison with the well established fluorenone absorption spectrum and in conjunction with polarization measurements the lowest electronic transitions were assigned. They are in order of increasing energies: 3A2(π,π*) π1A1 (f 1.5 ± 10−5), 1A2(π,π*) π1A1 (f = 1.5 · 10−4), B2(π,π*) · 1A1 (f = 6 · 10−3),and B2(π,π*) · 1A1 (f = 0.27). It is suggested that the orbitally forbidden, long axis polarized 1π,π* transition receives its intensity trough vibronic coupling from B2 states. The radiative liefetime, as determined from the emission quantum yield and measured lifetime of TF, compared with the same parameter of thiobenzophenone, allows the assignment of the emission as phosphorescence. The short phosphorescence lifetime (πp(77 K) = 15 μs; πp(77 K) = 0.035) implies a very effective spin‐orbit coupling, a property which is also manifested in the high intersystem crossing quantum yield θisc (S1 → T1) ∼ 1 at 77 K.
Der Dampfdruck‐Isotopie‐Effekt von deuterierten n‐Pentanen
Authors: Hörner Ch. , Höpfner A. , Schmeiser B.
Published: September 2012

Der Dampfdruck von n‐Pentan und die Dampfdruck‐Isotopie‐Effekte von 3 deuterierten n‐Pentanen (CD3CD2CD2CD2CD3, CH3CH2CH2CH2CH2D und CH3CH2CHDCH2CH3) im Temperatur‐Bereich zwischen ‐60 und +25°C werden mitgeteilt. Beim 3‐D1‐n‐Pentan wurde unterhalb ‐5°C ein “normaler” Dampfdruck‐Isotopie‐Effekt gefunden, oberhalb dieser Temperatur und bei 1‐D1‐ und D12‐n‐Pentan ist der Effekt im untersuchten Temperaturbereich invers. Die beobachteten Dampfdrücke und die aus ihnen abgeschätzten Verdampfungsenthalpien werden mit Literatur‐Daten verglichen.
Thermodynamische Beschreibung der Wüstitphase innerhalb ihres Existenzgebietes
Authors: Löhberg Karl , Stannek Wolfgang
Published: September 2012

Trotz einer Vielzahl von Untersuchungen konnte bisher die Wüstitphase in ihrem gesamten Existenzgebiet nicht allgemein thermodynamisch beschrieben werden. Eine vergleichende Gegenüberstellung von in der Literatur veröffentlichten Gleichgewichtsdiagrammen des Wüstits läßt die Unterschiede zwischen einzelnen Gleichgewichtsschaubildern nicht übersehen. Diese Differenzen, vor allem im unteren Temperaturbereich, werden durch eine häufig zu weitgehende Extrapolation einzelner Meßwertreihen hervorgerufen.

Die im experimentellen Teil dieser Arbeit erhaltenen Ergebnisse stimmen mit vielen in der Literatur veröffentlichten Meßwerten so gut überein, daß eine große Anzahl experimenteller Werte anderer Autoren in die analytische Auswertung mit einbezogen werden konnte. Aus der fülle der vorliegenden Meßwertpaare wurden diejenigen nicht berücksichtigt, die deutlich aus dem Trend der meisten Werte herausfielen. Aus den verbleibenden Meßwertepaaren konnte mittels Regressionsanalyse ein Gleichungssystem errechnet werden, das die isothermischen Meßwertkurven wiedergibt. Durch eine systematische Vereinfachung dieses Gleichungssystems gelang es schließlich, eine für den gesamten Wüstitbereich gültige allgemeine Größengleichung

zu ermitteln, die mit den errechneten Datensätzen für die zwei bezeichneten Temperaturbereiche das Wüstitgebiet mit großer Genauigkeit vollständig und lückenlos thermodynamisch beschreibt.
Pulsradiolyse von Gasen: Optisches Spektrum und Reaktionen von N4+ (oder N3+?) bei Atmosphärendruck
Authors: Dreyer J. W. , Perner D. , Roy C. , Volz A.
Published: September 2012

Durch Reaktionen von positiven Stickstoffionen mit Stickstoff wird ein Ion Nx+ gebildet, das ein breites kontinuierliches Absorptions‐spektrum mit einem Maximum bei 365 nm aufweist. Bei dieser Absorption handelt es sich wahrscheinlich um ein Dissoziationsspektrum, dessen Ursprung oberhalb von 600 nm liegt. Das Spektrum wird dem N4+ oder N3+ zugeordnet, wobei die Argumente für N4+ überwiegen. Das Nx+ reagiert in reinem Stickstoff mit Elektronen. Bei Zusatz von einigen einfachen Gasen wird das Verschwinden des Nx+ beschleunigt. Daraus werden Geschwindigkeitskonstanten für Ionen‐Molekül‐Reaktionen des Nx+ mit den Zusätzen bestimmt.
Pulsfluorimetrie unter Anwendung der Laplace‐Transformation I. Messung von Fluoreszenzlebensdauern II. Rotationsrelaxation von Rhodamin 6 G und von Perylen in optisch angeregten Zuständen in Abhängigkeit von der Anregungsenergie
Authors: Heiss Alois , Dörr Friedrich , Kühn Ingrid
Published: September 2012

Ein Fluorimeter samt Probe wird als lineares Übertragungssystem behandelt. Die Anregungspulsbreite ist von der Größenordnung der Abklingzeit oder länger. Der zeitliche Verlauf des Meßsignals entsteht durch Faltung der Abklingfunktion der Probe mit der Apparate‐funktion, die den Anregungsverlauf und die Antwortfunktion des Nachweissystems enthält. Der Vergleich der Laplace‐Transformierten der Fluoreszenzabklingfunktion mit derjenigen eines angenommenen kinetischen Modells liefert die kinetischen Parameter der Probe. Die Methode wird zunächst durch Messung der Fluoreszenzabklingdauern einiger organischer Verbindungen geprüft.

Mit dieser Methode wurde dann die Rotationsdepolarisation der Fluoreszenz von Rhodamin 6 G und von Perylen unter Anregung mit polarisiertem Licht in Abhängigkeit von der Erregerfrequenz gemessen. Es ergab sich ein ausgeprägter Gang mit der Höhe der primär angeregten Schwingungsenergie. Zur Deutung wird eine rasche “Erwärmung” der ersten Solvathülle mit Viskositätsminderung angenommen.
Kinetics of Redox Couples at Solid Electrodes III ‐ Ferro‐Ferricyanide System in Alkaline Media on Rotating Disk Electrodes of Polycristalline Perowskite Cobaltites La1‐xSrxCoO3, with x = 0.2 and 0
Authors: Cong H. Nguyen , Brenet J. , Chartier P.
Published: September 2012

Die Kinetik des Fe(CN)64‐/Fe(CN)63‐‐Redox‐Systems wurde mit einer aus Lanthankobaltit La1‐xSrxCoO3 (x = 0 oder x = 0,2) bestehenden rotierenden Scheibenelektrode studiert. Diese Legierungen haben eine Perowskite‐Struktur. Das Verhalten des Redox‐Systems ist dem an einer Manganitspinell‐Elektrode ähnlich. Die Ergebnisse sprechen sehr für eine Beteiligung des Fe(CN)63‐‐Ions an dem Oxydationsmechanismus des Fe(CN)64‐‐Ions. Eine Standardreaktionsgeschwindigkeitskonstante, ks, wurde für den Fall einer äquimolaren Lösung geschätzt zu ks = (3 ± 2) · 10−3 cm s−1.
Solid‐solid and Solid‐liquid Transitions in K2CO3, Na2CO3 and Li2CO3: Investigations to ≥ 5 kbar by Differential Thermal Analysis; Thermodynamics and Structural Correlations
Authors: Klement William , Cohen Lewis H.
Published: September 2012

Differential thermal analysis in hydrostatic apparatus yielded for K2CO3: solid‐liquid transition (905 ± 2°C intercept at 1 bar), 20.2 ± 0.6 deg kbar−1 slope and solid‐solid (421 ± 2°C), 16.8 ± 0.8 deg kbar−1, to ∼5 kbar; Na2CO3: solid‐solid (485 ± 3°C), 15.5 ± 0.5 deg kbar−1 and solid‐solid (356 ± 3°C), 11.3 ± 0.9 deg kbar−1, to ∼ 5 kbar; Li2CO3: solid‐liquid (724 ± 2°C), 6.2 ± 0.4 deg kbar−1 and solid‐solid (=420°C on heating, ≤407°C on cooling), ≤1 deg kbar−1, to ∼7 kbar. Thermodynamic data for the transitions are compared with these results. Structural similarities, quantitatively developed for these carbonates and also Rb2CO3. also are used in correlating data.
Chemical Reaction Kinematics XIX: Collision Complexes in Reactions of CH+, CH2+, NH2+ with H2
Authors: Mayer T. M.
Published: September 2012

The energy disposal characteristics of “long‐lived” collision complexes formed with high cross section in low energy collisions of CH+, CH2+ and NH2+ with H2 are examined. Product translational energy distributions are compared with those calculated using a simple statistical model of complex reactions based on the RRKM theory with conservation of angular momentum. The experimental translational energy distributions in all cases are found to be very non‐statistical, indicating that the internal energy of the complexes is not randomly distributed among all degrees of freedom. It is suggested that this is due to very short lifetimes (< 10−12 sec) of the complexes, and the translational energy release is determined mainly by conservation of angular momentum.
The Molecular Structure of Allenes and Ketenes II [1] Photoelectron Spectra, Absorption Spectra, and CNDO/S‐Calculations of Phenyl and Methyl Substituted Allenes
Authors: Runge W. , Kosbahn W. , Kroner J.
Published: September 2012

Ground states and low‐energy excited states of phenyl and methyl substituted allenes are studied by means of photoelectron spectroscopy, absorption spectroscopy and CNDO/S‐calculations.

The conjugative and inductive effects of the phenyl and methyl substituents on the charge distribution of the allenic moiety, and conformational effects (isomerization energies, angle of twist) are discussed on the basis of experimental and calculated properties. A UV band assignment for phenylallenes is achieved using correlations with excited states of benzene and phenylacetylene and CNDO/S‐calculations. The sequence of excited states of phenylallene, resulting from π→π* transitions corresponds to 1B2u < 1B1u < 1E2g(a) < 1E1u(a) < 1E1u(b) in benzene.

A tentative assignment for the excited states of allene and its methyl substituted derivatives is given. The proposed sequence of excited states of allene concerning the 2e → 3e transition is 1A2 < 1B2 < 1A1 < 1B2, in agreement with CNDO/S‐calculations.
Magnetooptische Rotationsdispersion von Benzophenon und Acetophenon
Authors: Feser Jörg A. , Winkler Johannes
Published: September 2012

Die magnetooptischen Rotationsspektren von Benzophenon und Acetophenon wurden gemessen und unter Berücksichtigung systematischer Meßfehler ausgewertet. Entgegen bisheriger Ansicht stehen sie dann in guter Übereinstimmung mit Messungen des Magneto‐Circulardichroismus. Durch Extrapolation der Spektren über den Meßbereich hinaus lassen sich die magnetooptischen Parameter von Übergängen abschätzen, die einer direkten Messung nicht zugänglich sind.
Untersuchungen zum Phasenverhalten von Gemischen aus Äthylen und Vinylacetat
Authors: Lindner Alfred , Luft Gerhard
Published: September 2012

Die gegenseitige Löslichkeit von Äthylen und Vinylacetat wurde für Vinylacetatgehalte bis zu 90 Gew.‐% bei Temperaturen von 20 bis 150°C und unter Drücken bis 2000 at untersucht. In diesem Bereich wurde eine Mischungslücke unterhalb 113 at gefunden. Dieser Druck ist höher als die in der Literatur angegebenen, extrapolierten Werte. Das heterogene Gebiet erstreckt sich im px‐Diagramm bei steigenden Temperaturen über einen immer kleiner werdenden Bereich des Vinylacetatgehalts. Der kritische Druck nimmt mit steigender Temperatur zu, durchläuft ein Maximum und fällt dann wieder ab. Das System zeigt somit ein ähnliches Dampf‐Flüssigkeitsgleichgewichtsverhalten wie Gemische aus Äthylen und Kohlenwasserstoffen z. B. Äthylen/n‐Heptan. Die Phasengrenzkurven sowie die kritische Kurve konnten mit befriedigender Genauigkeit rechnerisch erfaßt werden.