bluuebunny/crossref_metadata_2025 huggingface dataset:
Composition of ilmenite and provenance of zircon in northern Brazil
Authors: Knudsen Christian , Thomsen Tonny B. , Kalsbeek Feiko , Kristensen Jeppe A. , Vital Helenice , McLimans Roger K.
Published: March 2020

The mineral ilmenite (FeTiO3) is an important component of heavy-mineral placer deposits and constitutes the largest volume of valuable mineral in such deposits. The minerals zircon (ZrSiO4) and rutile (TiO2), which occur in lower concentrations than ilmenite in the deposits, have a greater value per ton – c. 1100 and 900 $/ton respectively – compared to ilmenite that ranges from 100 to 200 $/ton depending on its composition. Other minerals such as staurolite, sillimanite, amphibole and garnet are generally also present in placer deposits, but are of minor or no commercial value and, e.g. amphibole needs to be separated from the valuable heavy minerals which adds to the production cost.
Hurwitz Zeta Function of Two Variables and Associated Properties
Authors: Pathan M. A. , Bin-Saad Maged G. , Younis J. A.
Published: March 2020

The main objective of this work is to introduce a new generalization of Hurwitz-Lerch zeta function of two variables. Also, we investigate several interesting properties such as integral representations, operational connections and summation formulas.
Sistem Computer Based Test Try Out Uji Kompetensi Ners Berbasis Website Menggunakan Metode Prototyping (Studi Kasus: Fakultas Ilmu KeperawatanUniversitas Riau)
Authors: Sepriyanda Randy , Sari Rika Perdana , Fitrisia Yuli
Published: March 2020

Uji Kompetensi Ners Indonesia (UKNI) yaitu merupakan suatu proses untuk mengukur pengetahuan, keterampilan, dan sikap, sesuai dengan standar profesi guna memberikan jaminan bahwa perawat mampu melaksanakan peran profesinya secara aman dan efektif di masyarakat. Uji kompetensi ners Indonesia menggunakan komputer (Computer Based Test/CBT). Sebelum melaksanakan UKNI yang akan dilaksanakan nasional di perguruan tinggi program studi keperawatan, mahasiswa terlebih dahulu melakukan try out uji kompetensi ners sebagai langkah untuk mempersiapkan diri. Hal ini juga terjadi di Fakultas Ilmu Keperawatan Universitas Riau (FKp-UR). Selama ini kegiatan try out dilaksanakan secara konvensional yaitu menggunakan kertas sebagai media dalam melaksanakannya, sehingga menyebabkan mahasiswa menjadi tidak terbiasa dalam melaksanakan UKNI berbasis CBT. Berdasarkan permasalahan tersebut dibangun sebuah sistem CBT try out di FKp-UR, diharapkan dengan dibangunnya sistem tersebut, mahasiswa mampu membiasakan diri dalam menggunakan CBT pada saat melaksanakan UKNI. Hasil dari penelitian diketahui bahwa pada tahap pembangunan sistem menggunakan metode prototyping sebanyak empat kali putaran, sehingga kebutuhan dari user terhadap sistem dapat terpenuhi dengan maksimal.

 

Kata kunci: Fakultas Ilmu Keperawatan Universitas Riau ,Try Out, Uji Kompetensi Ners Indonesia,  Computer Based Test (CBT), user acceptence test, performance efficiency, usabilty, security.
Performance Analysis Of Star Schema Data Modeling On Library Data
Authors: Nurmalasari Dini , Zulvi Mutia Sari , Hanifah Puja
Published: March 2020

Lybrary information system whose data began to be organized from 2013 to the present, has recorded 5,477,618 library collections consisting of books, magazines, journals, CDs and so on. While the number of lending transactions continues to grow each year, although the development is not yet significant, it is recorded at around 3% every day. To help the process of analyzing library data patterns, a web-based system has been created using OLAP (Online Analytical Process) technology, with multidimensional data-based data modeling. To prove the simplicity of multidimensional data-based design, access time and join efficiency, in this study the selected data modeling is a star schema. The test results show that the star schema performance in library data is influenced by the amount of data, the cleaning process and the number of joins.
Game Genre untuk Permainan Pendidikan Pembelajaran Sejarah Berdasarkan Kebutuhan Pedagogi dan Learning Content
Authors: Novayani Wenda
Published: March 2020

Belajar sejarah adalah belajar tentang masa lalu, dimana pembelajaranya berisikan beberapa fakta tentang sejarah tersebut. Salah satu kesulitan dalam belajar sejarah adalah menghafal. Proses pembelajaran yang bersifat hafalan tersebut dapat diatasi dengan belajar yang menyenangkan dan menarik melalui permainan. Sebelum suatu permainan dibangun, terlebih dahulu harus menetapkan genre dari permainan tersebut. Pemilihan genre untuk permainan pembelajaran sejarah sangatlah penting karena akan menentukan efektif atau tidaknya dalam penyampaian isi cerita dari materi pelajaran, sehingga siswa tidak hanya mengetahui nama tokoh, tanggal dan kejadiannya saja tetapi juga dapat menyampaikan nilai moral dan patriotisme serta memiliki pemikiran yang kritis. Pada penelitian ini dilakukan pencocokan karakteristik dari lima genre game yang terdiri dari genre simulation, strategy, action, fuzzle dan role-playing  dan kesesuainya dengan pedagogi  pembelajaran sejarah.  Hasil dari penelitian ini yaitu masing-masing genre memiliki peluang yang berbeda, selanjutnya dibahas di dalam bab pembahasan, namun role playing genre kemudian diikuti genre game strategi merupakan genre yang sangat memungkinkan dan cocok untuk penyampaian pembelajaran sejarah yang sesuai dengan pedagogi pembelajaran sejarah.
Evaluación de la degradación de materia orgánica mediante técnicas de visión artificial y sensores
Authors: Reyes-Ordoñez Humberto Raúl , Ortiz-Torres Jonnathan Ismael , Álvarez-Vera Manuel Salvador , Cobos-Torres Juan Carlos
Published: March 2020

El monitoreo de gases, temperatura y humedad es importante para cuantificar el beneficio de microorganismos dentro de la descomposición de la materia orgánica. Debido a la dificultad de conseguir dispositivos automatizados, este tipo de monitoreo generalmente se lo hace de manera manual y con una resolución diaria para muestreo. Basados en esta problemática, el presente estudio buscó desarrollar un sistema automático de monitoreo mediante software libre y hardware DIY, capaz de monitorear la temperatura y humedad ambiental, la temperatura dentro de la materia en descomposición, así como los gases que se emiten durante la degradación de la materia orgánica (metano, amoniaco y dióxido de carbono), en dos contenedores diferentes. Uno de los envases tratados con microorganismos benéficos, mientras el otro envase no fue tratado. Se ha demostrado una reducción de gases contaminantes como metano, amoniaco y dióxido de carbono en un 93.09 %, 35.17% y 13.63%, respectivamente.
Derecho de petición, derecho a información y a recibir servicios públicos de calidad
Authors: Pozo-Calderón Edison Manuel , Garate-Amoroso Julio César , Cusi-Chambi Pedro Rolando , Quispe-Gabincha Alberto
Published: March 2020

La investigación tuvo como objetivo principal elaborar un proyecto de Ley Reformatoria a la Ley Orgánica de Garantías Jurisdiccionales y Control Constitucional, para garantizar el Derecho de Petición. Se fundamentó metodológicamente desde un trabajo descriptivo con diseño de campo no experimental, la muestra poblacional, se trabajó con 97 registrados en el Foro de abogados de la provincia de El Oro, Ecuador. Se vulneran múltiples derechos constitucionales entre estos el libre acceso a la información y a recibir servicios públicos de calidad, entre otros. Es por esta razón, que es sumamente necesario establecer un marco legal y un procedimiento rápido moderno y sencillo para que las instituciones reciban y atiendan nuestras peticiones sin la exigencia de formalidades innecesarias. El Derecho Constitucional de Petición debe cumplir su función y ser una herramienta que en forma ágil, rápida y sencilla, permita la vinculación de la ciudadanía y la Administración Pública o Privada.
CARACTERÍSTICAS EPIDEMIOLÓGICAS, CLÍNICAS Y TERAPÉUTICAS DE LA INFECCIÓN URINARIA EN PACIENTES DIABÉTICOS.
Authors: CORTEGANA-VENEGAS INDIRA ARIZU
Published: March 2020

Introducción: La infección urinaria en diabéticos constituye uno de los problemas importantes caracterizado por su unidad clínica y pluralidad etiológica. Objetivo: Generar conocimiento sobre las características, epidemiológicas, clínicas y terapéuticas de infección urinaria en diabéticos. Materiales y métodos: Es un estudio descriptivo de búsqueda bibliografía y se ha realizado en Pubmed, Medline, Scielo, bibliotecas de universidades nacionales e internacionales. Resultados: El 40.74% de casos fueron varones y 59.26% mujeres. Los malos hábitos de higiene, la presencia de

cálculos renales, un tiempo de enfermedad mayor de 10 años, vejiga neurogénica, uso de corticoides, infección urinaria previa están asociadas a infección urinaria en la población de diabéticos. Casi el 30% de los pacientes presentaron bacteriuria asintomática. El síntoma más frecuente fue la fiebre. Los síntomas presentes en el 75,7%. La incontinencia de esfuerzo 45.3%, de urgencia 40.6%, síntomas obstructivos 25%, irritativos 10.1%. Predominó Escherichia coli (57.41%), seguido de Enterobacter (8.33%) y Klebsiella pneumoniae (6.48%). La resistencia de E. coli fue elevada contra clindamicina, ácido nalidíxico, ácido pipemídico (100%) y cefuroxima (90.91%), amoxicilina clavulanato (81.25%), ampicilina (78.57%) y cefalotina (72.22%); buena sensibilidad para imipenem (76.92%), cefepime (72.73%), amikacina (72.41%), nitrofurantoína (70.37%), ceftriaxona(63.79%) y ceftazidima (61.11%). Conclusión: Las infecciones urinarias en los pacientes diabéticos son frecuentes y ocasionadas con más frecuencia por E. coli, con patrones de resistencia y sensibilidad que requieren medidas de intervención. La resistencia a los antibióticos se incrementa por el uso indiscriminado en pacientes con inadecuado control de su enfermedad.
IKASEKIN: DESIGN OF AN HOLISTIC LEARNING MODEL FOR THE DEVELOPMENT OF ENTREPRENEURIAL COMPETENCE
Authors: Zorrilla Calvo Pilar , Rincón Díez Virginia , Sáiz Santos María
Published: March 2020

Progress in the development of key educational competencies for labor insertion and entrepreneurship in our society, such as creativity, innovation and entrepreneurship, are being very numerous in recent decades. Teachers are promoting programs to implement new methodologies for achieving this goal. However, the university community lacks validated methodologies with measurement of results in the medium and long term. The aim of this paper is to present the validation methodology of the teaching method we have agreed to call IKASEKIN, to achieve educational competence "Ability to develop Creativity, Innovation and Entrepreneurship" in the university environment. This method has been implemented in the Marketing degree of the University of the Basque Country UPV/EHU. The results show that the entrepreneurial capacity of the students, after taking two subjects through Project Based Learning in the second year, is strengthened over time when taking a course directly involved with the entrepreneurship in the fourth year.
Montanhismo e Impacto Ambiental
Authors: Rodrigues Barbara Adelaide de Araujo Giron , Maia Tauan Nunes , Oliveira Cilene Lima de , Mota Gabriela Araujo Goes da , Alves Junior Edmundo de Drummond
Published: March 2020

O objetivo deste estudo foi investigar a relação entre o montanhismo e a conservação ambiental na cidade do RJ, mais especificamente, no complexo do Pão-de-Açúcar. A metodologia utilizada na pesquisa foi a observação participante e a análise de conteúdo, por meio de entrevistas com os interlocutores. O que se pode perceber, por meio dos discursos dos montanhistas ocasionais, foi uma busca pelo mínimo impacto e uma acusação da massificação dos usos dos espaços como responsável pelos impactos ambientais. Estes discursos foram relacionados, como modos de legitimização da prática, através da categoria “estilo de vida” que é extensão das preocupações ambientais para outras esferas da vida dos montanhistas.
A Brincadeira e o Jogo no Currículo da Educação Física
Authors: Maldonado Daniel Teixeira , Jesus Felipe de Souza , Freire Elisabete dos Santos , Sanches Neto Luiz
Published: March 2020

Neste artigo, investigamos como o jogo e a brincadeira são apresentados na segunda proposta provisória para a Base Nacional Comum Curricular (BNCC) na área de Educação Física (EF). Partimos do pressuposto de que há uma associação entre a política educacional mundial e a organização do sistema escolar brasileiro, com utilização de diversas ferramentas, incluindo a construção de um currículo comum como requisito de certas garantias de acesso ao conhecimento. Analisamos que a avaliação em larga escala pode mascarar essas garantias e que, desde a última década do século XX, os Parâmetros Curriculares Nacionais influenciaram o surgimento de diversas propostas curriculares no país, nas quais, predominantemente, a EF assumiu elementos da Cultura Corporal de Movimento, como a brincadeira e o jogo. Concluímos que a BNCC avança ao propor o tratamento pedagógico do jogo e da brincadeira como conteúdos, mas limita a presença destas temáticas à Educação Infantil e aos anos iniciais do Ensino Fundamental.
Entre Rio, Corpo e Lazer
Authors: Montenegro Gustavo Maneschy , Dias Mairna Costa , Paixão Hortência Teixeira da
Published: March 2020

O futlama se caracteriza por ser uma prática de futebol, jogado às margens do rio Amazonas, na cidade de Macapá – AP. O futlama é vivenciado em solo enlameado, no momento da vazante da maré, sem clara demarcação do espaço de jogo. A pesquisa teve os seguintes objetivos: identificar com que frequência um grupo de jogadores vivencia o futlama e analisar quais as motivações do grupo para a sua prática. Trata-se de uma pesquisa qualitativa, que combinou a pesquisa bibliográfica com a de campo. Os partícipes do estudo foram dez praticantes de futlama e as informações coletadas foram apreendidas por meio de observação e de entrevista semi-estruturada. Identificamos que o futlama é predominantemente jogado aos finais de semana, e a motivação dos jogadores está relacionada ao prazer durante o jogo, na liberdade de entregar-se a uma prática de lazer em contato com a natureza, na socialização e a presença afetiva de estar com os amigos.
Olavo Bilac e as Diversões Suburbanas
Authors: Santos Junior Nei Jorge dos
Published: March 2020

Neste texto, faremos o esforço de, através de um exercício historiográfico, pensar alguns significados atribuídos às manifestações da “cultura popular” nos arrabaldes dos subúrbios da cidade do Rio de Janeiro. Para tanto, a base de nossa argumentação se estabelece na tentativa de compreender as representações criadas pelas crônicas de Olavo Bilac, que não somente desqualificavam como também estereotipavam as práticas de lazer da região arrabaldina. Quanto ao recorte temporal adotado (1904-1906), levou-se em conta os textos produzidos na Revista Kos­mos, entre os anos de 1904 a 1906, período em que o autor teceu diversas críticas às formas de diversão suburbana, buscando redefinir usos e costumes considerados inadequados aos padrões daquilo que se julgaria civilizado.
GLOBALIZATION: LATEST TRENDS OR PERMANENT DEVELOPMENT DIRECTION?
Authors: SHAROV Oleksandr
Published: March 2020

The article views economic globalization in the theoretical and historical context. Analysing the origins of terminological interpretations, a new approach is being developed regarding the globalization’s objectivity and irreversibility as an inherent element in the development of the human community and international economic relations. Its commonalities and differences from the internationalization of the world economy are indicated. This raises the question of the globalization’s timing as a process, to answer which there are different approaches. The author examines the existing variants of periodization of globalization processes, as well as its peculiarities in the times of the global financial crisis of 2008–2010. He concludes that globalization is an objective process of the human community (economic) development of the area of its residence and that it is characteristic for the whole period of humanity’s existence. It is caused by the innate propensity of humanity for cooperation. However, it revealed its clear orientation after the Age of Discovery, intensified in the late nineteenth century (due to the industrialization of leading European nations and the colonization of the African continent and other non-European territories) and became a major trend in world economic development in the late 20th – early 21st centuries. Particular attention is paid to the problem of using a single national currency as an international means of payment (referring primarily to the US dollar), which is a feature of the current stage of globalization.

JEL: F60.
BILATERAL TRADE AND ENERGY RELATIONS BETWEEN THE EU AND THE COUNTRIES OF THE CASPIAN SEA REGION
Authors: Siskos Evangelos , DARVIDOU Konstantia
Published: March 2020

The European Union and the Caspian countries are important trade partners, although there is still potential for improvement of the cooperation considering the energy security and other issues. The paper analyses trends and structure of trade relations of the EU and Caspian countries. The trade between the regions is about 370 billion dollars. Exports of fuels to the EU are the main component of the trade between the regions. Therefore energy transportation projects are an important issue in the agenda for the international relations. A gravity model for the exports of fuels is presented. The model considers demand in the EU importing country, total fuel exports of an exporting Caspian country as an indicator of exporting supply capacities and in some cases energy self-sufficiency of an importing country. Distance turned out to make an insignificant effect on the energy trade. The analysis helps to determine undertraded and successfully exploited bilateral energy trade links between the individual EU and Caspian countries. The model showed that Greece is among the most relatively intensive importers of fuels from the Caspian region.

JEL: F10, F13, F15, Q4.
DEVELOPMENT TRENDS OF REGIONAL ECONOMIC INTEGRATION: METHODOLOGICAL ASPECT
Authors: LYZUN Mariia
Published: March 2020

The article investigates the transformation of approaches to understanding the processes of regional economic integration. The macro-region as a structural element of regionalism is explored. Criteria for typology of regional economic integration are systematized and divided into dichotomous and trichotomous. Factors influencing regional integration and current tendencies of its development are determined. A modern group of regional integration associations is identified, thus improving the existent typology. It includes regional and multilateral associations, hub and spoke regionalism, gravity agreements, plurilateral, bilateral, minilateral regionalism.

JEL: F15, F13, F60, R10.
Overview of Karl Barth's Theology: Focused on the Doctrines of God, Jesus Christ, and the Holy Spirit
Authors: Jee Sang-Hoon
Published: March 2020

ABSTRACT

      The purpose of this study is to have an overview of the theology of Karl Barth who is considered as one of the most influential theologians in contemporary Christian world. This study is of worthy in order to have an accurate grasp of the trend of modern Chriatian theology. After a brief survey of his life and works, this study provides an overview of Barth’s theology focusing on three major areas of his theology: the doctrines of God, Jesus Christ, and the Holy Spirit. Barth’s emphasis upon the transcendence of God, the centrality of Jesus Christ in Christian theology, and the importance of the Holy Spirit in the Trinity should not be ignored for better understanding of the modern Christian theology. In a word, Barth’s theology has continuity of, and, at the same time, discontinuity from liberal theology.

Keywords: Karl Barth, morder Christian theology, transcendence of God, centraliy of Jesus Christ, importance of the Holy Spirit, neo-orthodoxy, liberal theology
Analisis NPM, ROA, dan ROE dalam Mengukur Kinerja Keuangan
Authors: Winarno Slamet Heri
Published: March 2020

This research aims to determine the financial performance of an expedition company based on company profitability analysis. Indicators of profitability used include the ratio of Net Profit Margin (NPM), Return On Assets (ROA) and Return On Equity (ROE) in 2016 to 2018. Assessment of company performance is done by comparing the rentability ratio with the average ratio Industry and Bank Indonesia standards. The data used are financial statement data that is balance sheet and income statement report for year 2014 until 2016. Result of research indicate that overall rentability performance show good value, but compared with industry average performance of NPM year 2014 show less result Good, while ROA and ROE performance during 2015 and 2016 has not shown satisfactory results because it is below the industry average. Overall financial performance of the company can be said good.
A Review on ethnobotanical uses, biological activities and phytochemical aspects of Acacia senegal (L.) Willd. and Acacia seyal Delile. (Fabaceae)
Authors: René D Magnini  , Hilou A  , Millogo-Koné H  , Compaore S  , Pagès J-M  , Davin-Regli A
Published: March 2020

The genus Acacia is a group of tropical plants species used in folk medicine due to virtue of its many therapeutic properties. In this document, we review the Ethnopharmacology, biological and phytochemical activities of the two major plant species used. Although, several researchers has been done, Acacia senegal (L.) Willd. and Acacia seyal Delile. are among the species of the genus for which phytochemical study is limited, few bioactive compounds and properties described. Based on these current traditional uses, it is necessary to carry out more biochemical and pharmaceutical assays in order to identify the precise ingredient that supports the recommendation in traditional medicine. The characterization of the active compound that plays a role for treating human diseases (infection, cancer, etc.) represents a key step in phytochemical research of new compounds. Moreover, this information about the active compound will help the clinician/pharmacist to define a rational and combined use with the synthetic molecules for which resistance mechanisms are currently reported in clinical cases.

Keywords: Acacia Senegal; Acacia seyal; Antimicrobial; Biological activity; Phytochemistry; Tradional medicine
Ice Cream Rounds: The implementation of peer support debriefing sessions at a Canadian medical school
Authors: Hiranandani Rashi , Calder-Sprackman Samantha
Published: March 2020

Wellness programs exist for medical students but the opportunity to debrief challenging experiences is lacking. We piloted Ice Cream Rounds (ICRs) for University of Ottawa clerkship students during the 2018-2019 academic year to provide students a safe environment to discuss challenges. Students reported a decrease in stress, anxiety and burnout, and an improvement in collegiality as a result of ICRs. ICRs could benefit medical students at other universities. To successfully implement ICRs at your institution, we recommend obtaining funding for ice cream, having peer facilitators, and creating a safe and confidential environment where students feel comfortable to debrief challenging experiences.
Book Review: Reflective Dialogue: Advising in Language Learning by Satoko Kato and Jo Mynard
Authors: Takahashi Keiko
Published: March 2020

Reflective Dialogue: Advising in Language Learning is a comprehensive guide on understanding the field of advising in language learning. Language educators who are interested in exploring how to facilitate learner autonomy can learn the A to Z of advising in language learning from this book. The book provides practical resources for improving advising skills, recruiting and training learning advisors, as well as researching advising. Therefore, this book will be useful for new and experienced learning advisors who work with learners on a one-to-one basis and/or in classroom settings, as well as those who are involved in managing self-access centers.
MENGUJI PENERIMAAN TEKNOLOGI PADA PEMANFAATAN SISKEUDES DI PROVINSI JAMBI
Authors: Haswindy Septu
Published: March 2020

Studi ini bertujuan untuk mendapatkan bukti empiris tentang penerimaan tekhnologi aparatur pemerintahan desa terhadap penggunaan siskeudes dengan menggunakan kerangka model TAM 3. Sampel dalam studi ini ditentukan berdasarkan tipologi wilayah di Provinsi Jambi (tengah, timur dan barat). Untuk pengujian hipotesis, studi ini menggunakan program SmartPLS dengan menggunakan metode analisis Partial Least Square (PLS) . Hasil pengujian menunjukkan bahwa (1). Norma Subjektif (X1) berpengaruh positif dan signifikan terhadap pandangan (X2) (2). Pandangan (X2) berpengaruh positif dan signifikan terhadap Kegunaan (Y1) (3). Relevansi Pekerjaan (X3) berpengaruh positif dan signifikan terhadap Kegunaan (4). Kualitas Hasil (X4) berpengaruh positif dan signifikan terhadap Kegunaan (Y1) (5). Ketampakan hasil (X5) berpengaruh positif namun tidak signifikan terhadap Kegunaan (Y1) (6). Kemudahan kegunaan (Y2) berpengaruh positif dan signifikan terhadap Kegunaan (Y1) (7). Norma subjektif (X1) berpengaruh positif dan signifikan terhadap Kegunaan (Y1) yang dimoderasi oleh Pengalaman (X1.1) (8). Keyakinan diri sendiri terhadap komputer (X6) berpengaruh positif dan signifikan terhadap Kemudahan kegunaan (Y2) (9). Kesenangan dalam menggunakan komputer (X9) berpengaruh positif dan signifikan terhadap Kemudahan kegunaan (Y2) (10). Kenikmatan yang dirasakan (X10)  berpengaruh positif dan signifikan terhadap Kemudahan kegunaan (Y2) (11). Tujuan kegunaan (X11) berpengaruh positif dan signifikan terhadap Kemudahan kegunaan (Y2) (12). Kemudahan kegunaan (Y2)  berpengaruh positif dan signifikan terhadap niat perilaku (Y3) (13). Kegunaan yang dirasakan (Y1)   berpengaruh positif dan signifikan terhadap niat perilaku (Y3) (14). Norma subjektif (X1)  berpengaruh positif dan signifikan terhadap niat perilaku (Y3).
Kinetic Study of Maltodextrine Saccharification Process using Amyloglucosidase Covalently Immobilised
Authors: Batrinescu Gheorghe , Garganciuc Dana , Popa Ovidiu , Olteanu Mihaela
Published: March 2020

The membranes with immobilized enzymes have a double role, as a separation barrier and a biocatalyst. The membranes immobilize the enzymes in insoluble state by direct binding (e.g. covalent binding) or in soluble state, by adsorption at the separation surface, depending on the polymer nature and the membrane structure. The researches purpose was to emphasize the biocatalytic activity of a membrane-immobilized enzyme system. This paper relates the original results from the kinetic study of maltodextrine saccharification process. The dextrines are obtained by enzymatic hydrolise of starch with a-amilase.The process took place into an enzymatic membrane bioreactor equipped with an active membrane from brominated polyphenileneoxide with 28% bromination degree, having amyloglucosidase covalently immobilized. In this bioreactor carries on the conversion of dextrines to maltose and glucose, under the biocatalytic action of amyloglucosidase.
Koenigs-Knorr Synthesis of Galactofuranosides of Estrone, Androstanolone, 11a-Hydroxyprogesterone and Prednisolone
Authors: Predescu Nicoleta Florentina , Iga Silvia , Nicolescu Alina , Iga Dumitru Petru
Published: March 2020

Galactofuranosylation has been accomplished with 1-bromo-1-deoxy-2,3,5,6-tetra-O-benzoyl-a-D-galactofuranoside in the presence of cadmium carbonate as promotor. Glycosylation agent has been prepared by bromination of penta-O-benzoyl-ab-D-galactofuranoside with a solution of hydrogen bromide in glacial acetic acid. The precursor of the latter reaction has been produced by benzoylation of D-galactose that had been heated in pyridine while still warm. The following hydroxysteroids have been selected as being representative in terms of configuration, type of hybridization of carbon bearing hydroxyl, position on cyclopentenoperhydrophenantrene nucleus and, implicitly, the degree of shielding: estrone, androstanolone, 11-a-hydroxyprogesterone, prednisolone. The synthesized galactofuranosides have been characterized by 1H and 13C NMR as well as by chromatographic and chemical means.
Spineli Catalysts for the Catalitic Combustion of Toluen
Authors: Popovici Daniela , Bolocan Ion , Matei Vasile , Matei Dorina , Bombos Dorin , Dusescu Cristina
Published: March 2020

Three spinels catalysts with copper were synthetized: Cr2CuO4, Fe2CuO4 and (Fe,Cr)2CuO4 using the coprecipitation method, with a tartrate precursor type. The catalysts were characterized by atomic absorption spectrometry, X-ray diffraction spectrometry and IR and UV-Vis spectroscopy. The three catalysts were tested in toluene oxidation reaction and theirs performances were assessed by carbon dioxide amounts resulted from reactions.
The Evaluation of Ionic Conductivity in Polymer Electrolyte Membranes
Authors: Vaireanu Danut-Ionel , Maior Ioana , Grigore Alexandra , Savoiu David
Published: March 2020

A novel electrochemical cell for the evaluation of the ionic conductivity in polymer conducting membranes is proposed. This cell has the advantages of being able to determine with high precision the membrane thickness during electrochemical impedance spectroscopy measurements. A conductivity factor is also proposed in order to classify various membranes with respect to their conductivity versus a reference membrane, namely Nafion� 117.
Gap Junctions Involvement in Brain Hyperexcitability Phenomena
Authors: Margineanu Doru-Georg
Published: March 2020

Hyperexcitability pathologies, epitomized by epilepsy, are a largely unmet medical need, asking for conceptual developments on the functioning of networks of inter-communicating neurons and glia. Intercellular communication via gap junction (GJ) channels is largely present in mammalian brain. The GJ channels are made of proteins, essentially the connexins (Cxs) widely expressed in brain and in peripheral organs, the most abundant being Cx43. Expression level of Cx43 appears elevated in epileptic brains. Many different compounds actually modify the strength of GJ intercellular communication, though none is specific for GJs. Reference GJ blockers have anticonvulsant effects in numerous experimental models of epilepsy and some data suggest that GJ blockade might specifically act on epileptic hyper-synchrony, a feature hardly targeted by current antiepileptic drugs. The involvement of GJs in migraine is also suggested by recent results.
Role of Surfactants in Emulsion Polymerization Polymers by design
Authors: Dimonie Victoria L. , Sudo E. David , El-Aasser Mohamed S.
Published: March 2020

The determination of an emulsifier�s adsorption properties under conditions similar to those occurring during emulsion polymerization can provide important information to aid in the selection of the most appropriate surfactant for a given system. Results show that the latex particle size is dependent on the strength of emulsifier adsorption (DEads) at the particle/aqueous phase interface and is a function of the polymer polarity. Use of reactive surfactants can improve latex characteristics by reducing the desorption and migration of surfactant to film interfaces and minimize film water sensitivity. The fraction of bound surfactant can be maximized by using relatively low emulsifier concentrations and higher initiator concentrations.
Rebalancing Na+ and K+ Ionic Fluxes in Dopaminergic Neurons
Authors: Oprisan Sorinel A.
Published: March 2020

The ionic balance of living cells is maintained by Na/K ATPas pump. We found that the voltage dependence of the pump is not essential to maintain cellular homeostasis. We carried extensive numerical simulations in order to calibrate a realistic single-compartment Hodgkin-Huxley neural model of dopaminergic neuron. Bifurcation analyses of the computational model suggested that the half-activations of both Na+ and K+ ions involved in Na/K pump at the onset of action potentials are slightly shifted toward larger values in the absence of voltage dependence of Na/K pump. In addition, a voltage-independent Na/K pump is more stable and less sensitive to membrane potential perturbations. The model assumes that the internal Na+ and external K+ concentrations are constant.
A Comparative Study of Plasma Effects on the PET Surfaces
Authors: Topala Ionut , Dumitrascu Nicoleta , Popa Gheorghe , Durand Jean
Published: March 2020

Poly(ethylene terephatalate) (PET) films were treated with two different helium plasma sources, i.e. a dielectric barrier discharge working at atmospheric pressure and a capacitively coupled discharge at low pressure. After exposure in these two environments, the polymer films have an improved hydrophilic character, the magnitude of the effects is different. The increase of the surface energy was found to be almost entirely due to the increase of the polar component, whereas the dispersive component remains unmodified. The surface chemistry, analyzed by the ATR-FTIR technique, is not modified during the treatment. Thus, in the treated polymers spectra new absorbance bands are not identified. Still some variations of the PET characteristic bands were found. In the UV-Vis spectral range the modified polymers have modified absorption bands, associated with electronic transition in C=C and C=O bonds.
Analytical Study on Different Types of Tool Traces in Some Ancient Symbols Discovered at Sinca Veche - Temple, Romania
Authors: Ghisa Valentin , Popescu Ion V. , Belc Marius
Published: March 2020

In order to characterize and classify the composition of metallic trace sample that were extracted from religious inscriptions of Sinca Veche Temple, several elementary analytical determinations of certain metals were performed by AAS technique to certify their oldness. This study was focused on the composition diversity, especially for the areas in which we try to identify the origins of the tools in the religious representations. Samples were withdrawn artefacts.
In-situ Investigation of Sucrose Hydrolysis � Successful Link between Design of Experiment, RC1 and ReactIR System
Authors: Zajsek Katja , Gorsek Andreja
Published: March 2020

The reaction was catalyzed by strong acidic cation-exchange resin Amberlite IR-120 in H+ form. Four process parameters, including reaction temperature (J), sucrose mass concentration (gS), catalyst mass concentration (gC) and the rotational frequency of the stirrer (fm) at four levels were considered in this study. Relative contributions of the proposed influencing process parameters on hydrolysis time were estimated by analysis of the variance (ANOVA). The results showed that J had a substantial effect on the reaction time (78,3 %), the fm and gC had a smaller ones (7,9 % and 6,4 %, respectively), meanwhile the remain fraction to 100 % represents error (7,4 %). The optimum conditions, where the time required for complete sucrose hydrolysis would be the shortest, are: J= 79 �C, gC = 180 g/L, gS = 50 g/L and fm = 180 min�1. Although the presented results refer strictly to the selected case study and are specific within the observed ranges of selected process parameters, the proposed procedure shows their potential usage in general process design.
Surfactant involved in Copper Sulfide Nanocrystallites Synthesis
Authors: Simonescu Claudia Maria , Teodorescu Valentin Serban , Capatina Camelia
Published: March 2020

This paper presents the obtaining of copper sulfide CuS (covelite) from Cu(CH3COO)2.H2O and thioacetamide (TAA) system. The reaction was conducted in presence or absence of sodium-bis(2-ethylhexyl) sulfosuccinate (Na-AOT). The effects of various reaction parameters on the size and on the shape of nanoparticles have been examined. CuS obtained was characterized by X ray diffraction, IR spectroscopy, TEM � transmission electron microscopy and SAED selected area electron diffraction. The influence of surfactant to the shape and size of CuS (covellite) nanocrystals was established. The size of the nanocrystals varied from 10-60 nm depending on the reaction conditions such as quantity of surfactant.
New Coordination Compounds of Fe(III) with Organic Ligands
Authors: Flondor Mihaela , Rosca Ioan , Sibiescu Doina , Vizitiu Mihaela-Aurelia , Sutiman Daniel-Mircea , Cailean Adrian-Laurentiu , Cretescu Igor
Published: March 2020

In this paper the synthesis and the study of some complex compounds of Fe(III) with ligands derived from: 2-(4-chloro-phenylsulfanyl)-1-(2-hydroxy-3,5-diiodo-phenyl)-ethanone (HL1), 1-(3,5-dibromo-2-hydroxy-phenyl)-2-phenylsulfanyl-ethanone(HL2), and 2-(4-chloro-phenylsulfanyl)-1-(3,5-dibromo-2-hydroxy-phenyl)-ethanone (HL3) is presented. The characterization of these complexes is based on method as: the elemental chemical analysis, IR and ESR spectroscopy, M�ssbauer, the thermogravimetric analysis and X-ray diffraction. Study of the IR and chemical analysis has evidenced that the precipitates form are a complexes and the combination ratio of M:L is 1:2. The central atoms of Fe(III) presented paramagnetic properties and a octaedric hybridization. Starting from this precipitation reactions, a method for the gravimetric determination of Fe(III) with this organic ligands has been possible. Based on the experimental data on literature indications, the structural formulae of the complex compounds are assigned.
An Optimized Method for Electroless Pd Deposition onto Alumina Substrates
Authors: Petica Aurora , Anicai Liana , Pasuk Iuliana
Published: March 2020

An optimized electroless deposition procedure to form Pd membranes onto ceramic substrates involving the thermal decomposition of a Pd complex compound ([Pd (NH3)4] [PdCl4]) is discussed. This allowed a reaction efficiency of about 90-95%. The proposed method significantly diminishes the Pd wastes as compared with the classical procedure involving hydrazine based reduction step. A Pd layer of about 3-5�m has been uniformly deposited on the inner surface of the a-Al2O3 based substrate, being characterized by a very good adherence and light grey metallic appearance. Homogeneous films of Pd were obtained by annealing the deposited Pd layers at temperatures higher than 5000C in a hydrogen atmosphere. XRD and laser confocal microscopy techniques have been proved to be suitable to characterize the composition, thickness and uniformity of the formed Pd membranes.
Kinetics of the Thermal Disappearance of Radicals Formed During the Radiolysis of Aspartic Acid
Authors: Contineanu Mihai , Contineanu iulia , Neacsu Ana , Perisanu Stefan
Published: March 2020

The radiolysis of the isomers L-, D- and DL- of the aspartic acid, in solid polycrystalline state, was investigated at room temperature. The analysis of their ESR spectra indicated the formation of at least two radicalic entities. The radical, identified as R3, resulting from the deamination of the acid, exhibits the highest concentration and thermal resistance. Possible mechanisms of formation of three radical species are suggested, based also on literature data. The kinetics of the disappearance of radical R3 indicated a complex mechanism. Three possible variants were suggested for this mechanism.
The Influence of Curing Conditions on the Physical and Mechanical Properties of Magnesia Phosphate Cements
Authors: Paceagiu Jenica , Georgescu Maria
Published: March 2020

The paper brings information on the influence of curing conditions such as humidity, variable temperature and chemical solutions, on the compressive strength and weight variation of the magnesia phosphate binding materials, obtained from magnesite, mono-ammonia phosphate, borax and sand having a granulation ranging between 0.1-1 mm, with or without fly ash addition. The XRD and SEM�EDX analysis were made for obtaining information concerning the reaction products formed in phosphate magnesia binding materials cured in conditions of variable humidity.
The Effect of Chloride Concentration on Crevice Corrosion of some Welded Titanium Alloys
Authors: Popa Laurentiu , Radulescu Maria , Dinu Alice , Velciu Lucian , Branzoi Ioan Viorel
Published: March 2020

Geological disposal is identified by nearly all experts in the field of waste management as the only safe and sustainable option presently available, but the progress towards its implementation is slow. The nuclear waste must be safely storaged for hundreds of thousand years. Titanium alloys are some of the most promising candidates as container materials for the long-term disposal of high level nuclear waste (HLW) in rock salt formations. In the case of titanium waste containers, between the containers walls and the surrounding buffer material used to pack the disposal borehole some crevices can appear in the welded zone container/ shielding lid, under a biofilm etc. For this purpose we studied the effect of chloride concentration on crevice corrosion of some welded titanium alloys (Grade 2 and Grade 12, respectively) in chloride solutions at 90oC by electrochemical methods (Ecorr vs time, potentiodynamic tests).
Prediction of Protein Secondary-Structure by Monte Carlo Simulation
Authors: Woinaroschy Alexandru
Published: March 2020

Proteins have four structural categories. The primary structure is the amino-acid sequence of the polypeptide chain. The secondary structure is the conformation, representing of the backbone (a-helix or b-sheet). The knowledge of protein structure has a paramount theoretical and practical importance (e.g. cancer disease) and a huge effort of research was devoted to this subject. Despite the fact that several methods were developed for protein secondary-structure prediction, there are no consensuses of their results. In this paper was proposed an new, original, method to investigate the influence of the number of amino acids and the percentage contents in the twenty amino acids for the prediction of protein secondary-structure, respectively Monte Carlo simulation using a multilayer neural networks. The method is very promising in connection with the use of large data bases.
Porphyrin - Based Supramolecular Nanotubes Generated by Aggregation Processes
Authors: Ion Rodica-Mariana , Boda Daniel
Published: March 2020

Porphyrins can form a variety of structures from linear head-to-tail or J-aggregates to fractal aggregates with different and specific photophysical properties. In this paper, the controlled aggregation of meso-5 ,10, 15, 20-sulfonato-phenyl porphyrin (H2TPPS44-) was studied at room temperature. Structure of the aggregates was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-visible spectroscopy. TEM and SEM results indicated the formation of organized nanostructures from the porphyrin derivative. UV-visible-NIR spectroscopic data showed broad red-shifted Soret band, indicating J-aggregation among the monomer units. Conjugate effect of lateral p-p interaction among the tetrapyrrole cores and hydrophobic interaction among the peripheral phenyl rings is believed to lead to the organized nanostructures. Such aggregates have the size of 5-6 nm in solution. The columnar structure formed by porphyrins has a length of 5 to 27 porphyrin unities.
Oxygen Transfer Efficiency of the Aeration Process in Refinery Waste Water Treatment
Authors: Stanojevic Miroslav , Jovovic1 Aleksandar , Radic Dejan , Pavlovic Milan
Published: March 2020

This paper presents the results of an experimental investigation of aeration of water with a corresponding mass concentration of waste motor oil depending on the height of the liquid column for varied flow of air introduced into the water. The aeration process for water column heights of 1 and 2 m were investigated. The purpose of investigations performed on an experimental installation was comparison of technical indicators of the aeration process depending on the height of the water column and air flow in order to achieve more efficient purification of waste water.
The Antimicrobial Acitvity and Quantitative Structure - Biological Activity Relationships Evaluation of Some Novel 2-Hydroxybenzamide Derivatives
Authors: Ienascu Ioana M. C. , Lupea Alfa Xenia , Hadaruga Dan , Hadaruga Nicoleta , Popescu Iuliana M.
Published: March 2020

Based on our studies of the biological activity of 2-hydroxybenzamide derivatives, we evaluated the antimicrobial activity of some novel compounds from this class (esters, hydrazides, hydrazones), against bacterial (Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Bacillus cereus) and fungical (Sacharomyces cerevisiae, Candida albicans) strains using the disc-diffusion method under standard conditions. It was found that all tested compounds present a good activity against the tested microorganisms and they were more active against Candida albicans. The established minimum inhibitory concentration (MIC) values were ranged between 10-2- 3.6�10-4 mol/L and were used to obtain some quantitative structure-biological activity relationships using HyperChem 5.01 program for molecular modelling and conformational analysis. The established equations using different parameters present correlation coefficients statistically ensured.
Mathematical Model of the Liquid Membrane Extractive Column. Sensitivity to Operating Parameters
Authors: Dinculescu Daniel , Lavric Vasile
Published: March 2020

The extraction-back extraction column of low concentration species by means of an organic closed loop flow, considered as liquid membrane, was modelled then simulated, using some simplifying assumptions. The main hypotheses are: the aqueous phase is perfectly mixed, the drops of the organic phase are lumped into a plug-flow inner cylinder co-axial with the aqueous phase, and the organic phases under the sieve and on the top of the column are perfectly mixed also. The dynamic model of the extraction-back extraction column is, then, applied to the recovery of the hydrocarboxylic acids. The mathematical model, reduced through orthogonal collocation to a system of ordinary differential equations, was solved using a self-adaptive (RK)-type method. Its validation was done based on batch experimental data; the optimal model parameters (the specific mass transfer coefficients for both extraction and back-extraction zones), ensuring the agreement with the experiment, were found by means of a modified genetic algorithm technique. Then, a sensitivity analysis was done, to grasp the behaviour of the system with respect to the main operating parameters - the organic flow in the closed loop, the partition coefficient and the buffer volume.
Temperature Dependence of the Phospholipids Bilayers Stability, Studied by FTIR Spectroscopy
Authors: Severcan Feride , Agheorghiesei Catalin , Dorohoi Dana-Ortansa
Published: March 2020

The temperature induced modifications in the lipid bilayers in water were studied by using 2D-FTIR Correlation Spectroscopy. The spectral range analysed in this paper corresponds to symmetric and asymmetric stretching vibrations of the �CH2 groups from the acyl chains of DPPC. Autocorrelation peaks at 2916 cm-1 and 2848.5 cm-1 and asynchrone modifications in the spectral ranges 2916-3000 cm-1 and 2848-3000 cm-1 were evidenced. The revealed modifications indicate changes in the conformers of the hydrocarbon chains in the phase transition from the gel to liquid crystalline phases, as well as the variations in the concentration of the two phases with temperature increasing.
Obtaining of Phtalocyaninic Dyes Using Solvothermal Methods
Authors: Boscornea Cristian , Grigoriu Nicoleta , Tararabasanu Mihaila Doina , Robu Monica
Published: March 2020

Metallo- phtalocyanines were obtained in good yields by the solvothermal method, a new and original synthesis method, optimized in real laboratory conditions. The structures were characterized by elemental analysis, UV-VIS and IR spectroscopy. Some of the compounds (iron phthalocyanine) were assigned by M�ssbauer spectroscopy.