bluuebunny/crossref_metadata_2025 huggingface dataset:
Lipótváros: a pesti City
Authors: Gyáni Gábor
Published: November 2023

A dualizmus korában felgyorsult a népesség városba tömörülése: Magyarországon 1869-ben a népesség 13%-a, a korszak végén 20%-a élt városokban.1 1869-ben, a városegyesítés küszöbén Pest, Buda és Óbuda lakosainak száma együttesen 280 ezer fő volt; 1920-ig Budapest népességszáma 930 ezer főre emelkedett. A két háború között a főváros demográfiai növekedése lelassult, és a súlypont átkerült az elővárosokba. Az 1945 előtti utolsó népszámlálás tanúsága szerint Nagy-Budapest lélekszáma 1,7 millió fő volt. A nagyvárosi fejlődés rohamos mértékét jól mutatja, hogy 1870 és 1940 között öt és félszeresére nőtt a magyar főváros és elővárosainak a teljes népességszáma.
Chancen und Risiken von psychischen Diagnosen
Authors: Hagmann-von Arx Priska
Published: November 2023

Der vorliegende Beitrag handelt von Diagnosen von psychischen Störungen bei Kindern und Jugendlichen. Kinder und Jugendliche mit einer psychischen Diagnose sollen die bestmögliche Unterstützung erhalten und ihren Bedürfnissen entsprechend gefördert werden. Für die Heil- und Sonderpädagogik bedeutet dies, über die Diagnose hinauszudenken: Der Mensch und sein individuelles Erleben und Verhalten stehen im Zentrum, nicht die Diagnose. Dieser Beitrag beschäftigt sich mit den Chancen und Risiken von psychischen Diagnosen, um Fachpersonen für mögliche Konsequenzen von psychischen Diagnosen zu sensibilisieren.
Umgang mit Diagnosen im Autismus-Spektrum
Authors: Liesen Christian , Krieger Beate
Published: November 2023

Die Zahl von Kindern und Jugendlichen mit einer Autismus-Spektrum-Störung (ASS) nimmt weiter zu. Die Wartelisten für eine Abklärung sind lang: Diagnostische Möglichkeiten werden differenzierter, aber auch komplexer. Müssen die Massnahmen im Gleichschritt immer weiter anwachsen? Zweifel sind angebracht, wie der Beitrag argumentiert. Anhand der sechs Leitprinzipien der «National Guideline for the Assessment and Diagnosis of Autism Spectrum Disorders in Australia» und eines Fallbeispiels leiten wir Empfehlungen für den Umgang mit der Diagnose Autismus-Spektrum ab.
SIMULAÇÃO NUMÉRICA E DIMENSIONAMENTO DE PERFIL U COM DUPLO ENRIJECEDOR DE BORDA FORMADO A FRIO SUBMETIDO À COMPRESSÃO
Authors: Diogo Frederico Artoni Leal , Maia Wanderson Fernando
Published: November 2023

The present work brings a numerical, non-linear physical and geometric analysis using the Finite Element Method, of cold-formed steel channel with complex edge stiffeners, using the Ansys software. The simulations employed different magnitudes of initial imperfections and seeking to find the critical buckling loads and failure modes, observing local, distortional buckling and the interaction between both. The results obtained were compared with experimental tests, performed by Young e Yan (2002) and with the values proposed by the brazilian standard ABNT NBR 14762:2010, using the Direct Strength Method. The numerical analysis proved to be quite efficient, producing interesting results compared to the experimental ones, showing the reliability of this adopted method. The initial imperfections adopted showed that, for the same section, it was not the same magnitude that produced the best results, emphasizing the importance of your choice. The procedure of ABNT NBR 14762:2010 proved to be conservative for sections in which local buckling predominated and against security for sections in which the distortional buckling predominated.
Uma modelagem mais realista do tempo de descoberta de vizinhos para mecanismos de duty cycle assíncrono baseados em escalonamento
Authors: Trabbold Beatriz , Carrano Ricardo C. , Passos Diego , Oliveira Cledson de
Published: November 2023

O ciclo de trabalho é um mecanismo fundamental para redes sem fio com dispositivos operados com bateria, como as redes de sensores sem fio. Devido à sua importância, este tipo de mecanismo é empregado em diversos protocolos de acesso ao meio. Nos ciclos de trabalho assíncronos baseados em escalonamento, os nós ativam e desativam suas interfaces de rádio de acordo com um escalonamento de slots preconcebido que garante alguma sobreposição de tempo de atividade entre dois nós, independente da diferença entre seus relógios internos, o que torna a comunicação possível. Este artigo apresenta um novo modelo para o Tempo de Descoberta de Vizinho (ou NDT, do inglês Neighbor Discovery Time). Diferente dos modelos anteriores, este trabalho modela o cenário onde as bordas dos slots dos escalonamentos de nós vizinhos podem não estar perfeitamente alinhadas – o caso mais comum na prática.
Lógica Fuzzy Aplicada a Escalonamento Horizontal
Authors: Silva Sérgio N. , Silva Lucileide M. D. da , Fernandes Marcelo A. C.
Published: November 2023

Este trabalho apresenta uma abordagem baseada em lógica Fuzzy para o escalonamento de réplicas em um ambiente Kubernetes. O sistema proposto, denominado FHS (Fuzzy-based Horizontal Scaling), foi comparado ao mecanismo padrão de escalonamento do Kubernetes, o HPA (Horizontal Pod Autoscaler). A comparação levou em consideração o consumo de recursos, o número de réplicas utilizadas e aderência aos Acordos de Nível de Serviço (SLAs - Service-Level Agreements) de latência. Os experimentos foram realizados em um ambiente com uma máquina virtual (VM) executando o cluster Kubernetes, outra VM com o JMeter para gerar demandas de tráfego e o controlador FHS no host. Os resultados demonstraram que o FHS obteve uma redução no consumo de CPU, utilizou menos réplicas para uma mesma condição de estresse e apresentou taxas de violação dos SLAs de latência mais distribuídas em comparação ao HPA, que teve valores mais concentrados. Esses resultados indicam que o FHS oferece uma solução mais eficiente e customizável para o escalonamento de réplicas em ambientes Kubernetes.
Análise de Desempenho de um Esquema de Acordo de Chaves de Conferência para IoT
Authors: Marim Mateus Coutinho , Coelho Kristtopher K. , Vieira Alex B. , Nacif José Augusto M. , Nogueira Michele , Silva Edelberto Franco
Published: November 2023

Wireless networks and their recent applications in the Internet of Things (IoT) have the evident necessity of mechanisms that increase its exchanged data reliability and integrity. Therefore, key agreement schemes are strong candidates to meet these requirements. Considering the resource constraints in IoT networks, verifying these limitations is vital. In this work, an analysis of computational feasibility and a proposal for using a one-way key agreement method based on second-degree equations for an IoT environment are performed. For the analysis, we simulated a network of up to 50 devices. It considered memory consumption, the time for session key generation, the size of the generated key, and the overhead in time for message exchange. The results show that the method applies to IoT networks, presenting a linear growth in the key agreement time and constant processing even with increasing the key size.
Comunicação Óptica Sem Fio Subaquática: Caracterização de Desempenho da Luz Vermelha
Authors: Reis Gabriel M. , Silva Douglas D. M. , Vieira Alex B. , Vieira Marcos A. M. , Vieira Luiz F. M. , Nacif José Augusto M.
Published: November 2023

A comunicação subaquática sem fio (UWC) é de grande interesse para aplicações militares, industriais e para a comunidade científica, pois desempenha um papel importante, como por exemplo, na vigilância tática e no monitoramento da poluição da água. A UWC pode ser realizada usando ondas acústicas, de radiofrequência (RF) e ópticas. Em contraste com as ondas acústicas e de RF, a comunicação óptica sem fio subaquática (UWOC) pode suportar taxas de dados mais altas com baixos níveis de latência. Entretanto, as propriedades do canal de água representam desafios significativos para a UWOC, o que exige soluções de rede eficientes. Nesse sentido, este artigo investiga o desempenho de um sistema UWOC com um transmissor no espectro de luz vermelha em um ambiente aquático raso e claro. Foram realizadas avaliações sobre o impacto no desempenho da transmissão causado diodos de laser (LDs) nesse comprimento de onda. Os resultados apresentados mostram o impacto na comunicação causado pelo meio, pela distância entre os nós e pelo tipo de transmissor usado. Além disso, eles demonstram a viabilidade do uso da luz vermelha na comunicação, que atingiu uma taxa de dados máxima de 5,08 kbps com 5 cm de distância entre os nós.
Fallverstehen, Begegnung und Verständigung
Authors: Hildenbrand Bruno
Published: November 2023

Staufen in Baden-Württemberg and Lüdge in North Rhine-Westphalia stand for the biggest youth welfare scandals of recent years. This book is dedicated to the question of how this can be stopped and the answers to it. The aim is to increase professional expertise in child protection. A pattern of action suitable for this purpose, discovered in our own research, is presented. These results were obtained in the course of a nationwide research project that lasted twelve years. Project leader was the author, at that time a clinical sociologist at the Friedrich Schiller University in Jena. This book is aimed at professionals in youth welfare, social pedagogy, law enforcement and medicine - also at those with political responsibility.
Effectiveness of Contextual Schema Therapy for Extreme Perfectionism and Emotion Regulation in Individuals with Perfectionism Disorder
Authors: Sohrabi Mansureh , Bakhtiarpour Saeed , Sohrabi Faramarz , Eftekhar Saadi Zahra , Asgari Parviz
Published: November 2023

Background: Individuals are consistently influenced by ineffective core beliefs known as maladaptive schemas that develop during childhood and can pave the way for the appearance of problems such as extreme perfectionism. Therefore, therapeutic approaches are needed that can be effective for these schemas. Objectives: The present study aimed to investigate the effectiveness of contextual schema therapy (CST) on perfectionism and emotion regulation in individuals with perfectionism disorder. Methods: In this study, 12 individuals diagnosed with perfectionism disorder visiting the psychological service centers in Tehran in 2022 were purposively selected for this quasi-experimental study with a pre-test, mid-test, and post-test design. The participants underwent CST in 40 one-hour sessions and completed the Positive and Negative Perfectionism Scale and Emotion Regulation Questionnaire in all three stages of the assessment. The data were analyzed using the repeated measures analysis of variance (ANOVA) in SPSS-26. Results: The mean and standard deviation (SD) of perfectionism in the pre-test, mid-test, and post-test phases were 151.08 ± 18.97, 94.25 ± 12.48, and 67.58 ± 5.41, respectively. Moreover, the mean ± SD of emotion regulation in the pre-test, mid-test, and post-test phases were 40.25 ± 8.95, 45.50 ± 8.12, and 50.08 ± 7.94, respectively. The results demonstrated that the CST was effective for perfectionism across all assessment stages (P < 0.001); however, this influence was not significant for emotion regulation during the mid-test stage. Conclusions: Contextual schema therapy led to a reduction in extreme perfectionism and an improvement in emotion regulation in individuals with perfectionism. It is suggested that CST be applied in psychological service centers to reduce perfectionism and emotion regulation strategies in clients.
The Effectiveness of Psychodynamic Group Therapy on the Components of the Sense of Coherence Among Patients with Colon Cancer
Authors: Andalib Leila , Rezaei-Jamalouei Hasan , Emami Seyed Mohammad Hasan , Ansari Shahidi Mojtaba
Published: November 2023

Background: Cancer causes several social and psychological problems and responses, such as denial, anger, and feelings of guilt, which eventually lead to the patient’s psychological coherence collapse. Objectives: The present study aimed to evaluate the effects of psychodynamic group therapy on the components of the sense of coherence (SOC) among patients with colon cancer. Methods: This quasi-experimental study was conducted using a pretest-posttest design with a control group and follow-up on all patients with colon cancer treated at the Poursina-Hakim Treatment Center in Isfahan, Iran, during the spring of 2022. Then, 28 patients were selected using convenient sampling and divided randomly into two 14-member groups: the psychodynamic therapy group (receiving 12 treatment 100-minute sessions) and the control group. The participants completed the Sense of Coherence (SOC) Scale in three pretest, posttest, and follow-up stages. The research data were analyzed using repeated measures ANOVA and the Bonferroni post hoc test in SPSS software version 26. Results: The mean ± SD of the posttest score of comprehensibility in the psychodynamic therapy group was 40.57 ± 7.20, which was different from the pretest 32.42 ± 5.98. Moreover, the mean ± SD of the posttest score of meaningfulness in the psychodynamic therapy group was 37.57 ± 7.53, which was also different from the pretest 31.14 ± 6.16. Psychodynamic therapy effectively enhanced comprehensibility (P = 0.001) and meaningfulness of life (P = 0.032) among patients with colon cancer. The therapeutic effect remained stable over time only in the comprehensibility component. The stability of the intervention effects on meaningfulness was not observed over time. Additionally, the therapeutic effect on the manageability component was not significant. Conclusions: Based on these results, psychodynamic therapy could affect the patients’ comprehension of the current circumstances and the meaningfulness of life and help their psychological adaptation.
Exploring α-Glucosidase Inhibitory Peptides: Structure-Activity Relationship Analysis and Perspectives for Designing Potential Anti-diabetic Agents
Authors: Mohd Rodhi Ainolsyakira , Yap Pei Gee , Olalere Olusegun Abayomi , Gan Chee Yuen
Published: November 2023

Context: α-Glucosidase (AG) inhibitory peptides represent a promising new class of therapeutic agents for the treatment of diabetes. However, there is a need to further understand the mechanisms and properties of these peptides. Evidence Acquisition: In this comprehensive review, AG inhibitory peptides were categorized into three groups based on their length: Short, medium, and long peptides. Data from the BioPEP-UWM database and recent publications were gathered to conduct a structure-activity relationship analysis for these peptides, focusing on identifying their reactive residues and AG binding sites. Results: Through extensive examination, five substrate analogs (Trp376, Asp404, Ile441, Met519, and Phe649) and two catalytic residues (Asp518 and Asp616) were identified as the preferred inhibitory sites on AG. Furthermore, amino acid preferences and their positionings at different terminals on peptides, including the ultimate (N1 and C1), penultimate (N2 and C2), and antepenultimate (N3 and C3), were explored. Our findings revealed that these peptides were predominantly hydrophobic and tended to contain hydrophobic amino acids with hydrophobic alkyl/aryl side chains (such as lysine, glutamine, proline, and/or arginine). To gain further insights into peptide-AG interactions, docking analysis was performed, which highlighted the significance of hydrophobic bonds as the primary mode of interaction. Conclusions: By pooling all the findings, this review provided essential and practical information for the design and discovery of peptide-based anti-diabetic agents.
Výsledky dokazování přesahující skutková tvrzení stran a možnosti jejich použití v civilním sporném řízení
Authors: Mazel Filip
Published: November 2023

Článek se zabývá otázkou využitelnosti těch skutkových zjištění vzešlých z provedeného dokazování, která přesahují rámec toho, co strany na podporu svého procesního stanoviska tvrdily, v civilním sporném řízení. Na uvedenou problematiku je přitom nahlíženo prizmatem zásady projednací, jejímž důsledkem je nepřijatelnost bezbřehého přihlížení ke všemu, co v řízení vyšlo najevo, při zjišťování skutkového stavu. Je proto usilováno o nalezení přiměřené míry toho, kdy soud může činit skutková zjištění i nad rámec předchozích tvrzení stran. V neposlední řadě jsou zohledněny i dopady uvedeného postupu soudu na předvídatelnost jeho rozhodnutí.
Protocolo de auditoria médica para anestesiología como medida preventiva de procesos medico legales
Authors: Caracila Choque Patricia , Tapia Benito Tatiana Angelica
Published: November 2023

Objetivo General. Implementación de prueba piloto del expediente clínico utilizado en anestesiología  para prevenir procesos medico legales. Objetivos Específicos. a) Describir los fundamentos teóricos, conceptuales y contextuales relacionados con las prácticas de anestesiología. b) Evaluar el cumplimiento de los registros de anestesiología de acuerdo a la norma de anestesiología c) Proponer en base a los resultados un plan de mejora continua para mejorar el cumplimiento de los registros de anestesiología. Metodología. Se trata de una investigación cuantitativa, experimental,  observacional, retrospectivo y descriptivo; se evaluaron 283 historias clínicas. Resultados. De las 283 historias clínicas evaluadas 227 (80%) historias clínicas cuentan con el consentimiento informado de anestesiología y 56 (20%) no registran; en relación a las notas preanestésicas 258 (91%) historias clínicas contienen la nota preanestésica y 25 (9%) no registran; en relación al registro transanestésico 263 (93%) historias clínicas contienen el registro y 20 (7%) no cuentan con el registro; finalmente en relación a la nota posanestésica 251 (89%) historias clínicas registran la nota posanestésica y 32 (11%) no registran la nota. Conclusiones. De acuerdo a los resultados se observa que existe el incumplimiento a las normas de Diagnóstico y Tratamiento de Anestesiología y del Manejo del Expediente Clínico. Por la tanto, es importante implementar un plan de mejora continua, mediante capacitaciones y auditorías programadas, para fortalecer el cumplimiento de las normas para prevenir procesos médico legales.
Sepsis con afectación peritoneal por BCG: A propósito de un caso
Authors: Condori Bustillos Rocio , De la Fuente Olmos María Rebeca , Villacastín Ruiz María Elena , Alvarez Garcia Marta
Published: November 2023

La instilacion intravesical de BCG  es  utilizado en el tratamiento del carcinoma vesical in situ, generalmente es bien tolerada  y  con raras complicaciones, sobre  estas se ha descrito mecanismos por diseminación hematógena (con pruebas microbiológicas e histopatológicas positivas) o por hipersensibilidad tipo IV (Pruebas microbiológicas negativas, granulomas y buena respuesta a corticoides) o mixto. Presentamos el caso  de un paciente con Carcinoma vesical en tratamiento con instilaciones intravesicales de  BCG, con factores de riesgo de lesión de la barrera urotelial, comienza con fiebre hasta llegar a una sepsis,  con cultivos: negativos y en pruebas de imagen: engrosamiento peritoneal con adenopatías necróticas de  nueva aparición, negativas para malignidad  tras la biopsia dado el antecedente neoplásico del paciente,  patrón miliar en TC tórax, evolucionando con buena respuesta a antituberculosos. Dada la relación temporal los hallazgos clínico, radiológicos e histopatológicos se llega al diagnóstico de Sepsis por hipersensibilidad a BCG con afectación peritoneal.
Path to Improve the Professional Quality of Students Majoring in Financial News: Micro Evidence from 300 Questionnaires from Three Universities
Authors: Zhang Chunhua , Jin Yanjun
Published: November 2023

There must be a better match between the supply of financial news graduates in colleges and the media's demand for financial news talents. Based on 300 questionnaires and in-depth interviews from three universities, namely Shanghai University of Finance and Economics, Nanjing University of Finance and Economics, and Jiangxi University of Finance and Economics, this paper uses the interview method to excavate the professional quality improvement path for majoring in financial news students. Results reveal that undergraduates majoring in financial news have problems such as low professional identity, insufficient recognition of the discipline system, poor sense of professional identity, common matching between job selection and majors, and worrying about the status quo of professional literacy. Therefore, the improvement of the professional quality of students majoring in financial news and the reform of the training program needs to drive the professional quality of students in multiple dimensions, change their professional cognitive problems, strengthen their professional identity, and achieve an effective match between supply and demand of financial media professionals.
EXTRACTION AND RECOVERY OF PALLADIUM AND PLATINUM ACROSS HOLLOW FIBER SUPPORTED LIQUID MEMBRANE
Authors:   , Wongkaew Krirkratthawit
Published: November 2023

The extraction and stripping of palladium from flexible printed circuit board (FPCB) wastewater, and platinum from gold refining (GR) wastewater via hollow fiber supported liquid membrane were studied. In case of the separation of palladium, the extraction and stripping reached 96% and 91%, respectively by using 5%(v/v) LIX84-I dissolved in kerosene. Other conditions were feed solution at pH 2, stripping solution consisting of 0.8 M thiourea and 1 M hydrochloric acid, and flow rates of feed and stripping solutions at 100 ml/min. For the extraction of platinum, 96% extraction and 88% stripping were obtained by using 10%(v/v) Aliquat 336 dissolved in kerosene while other operating conditions were similar to the separation of palladium from FPCB wastewater. The separation factor of platinum in GR wastewater from palladium, gold, copper and zinc ions were approximately 17, 249, 970 and 1276, respectively. Additionally, natural solvents, i.e., sunflower oil, coconut oil and soybean oil were used instead of kerosene in the separation of platinum from GR wastewater. It was found that sunflower oil gave the highest platinum extraction, however, only 65% was attained compared with kerosene. In addition, the estimated mass transfer results of the extraction of palladium by the mathematical model based on diffusion, the reaction at the interface of feed and liquid membrane phases, and the accumulation of the metal ions in liquid membrane phase were obtained. The deviation from the experimental results was lower than 5%.
Design of monolith-typed reactor for vehicular hydrogen production
Authors:   , Jiwanuruk Tara
Published: November 2023

This thesis studied the development of a small scale multifunctional reactor for hydrogen production for on-board fuel cell. The study was divided into three parts as follows: i) the comparison between the flow arrangements of the thermally coupled micro reformer (TMR) ii) the effect of the flow arrangement on the micro membrane reformer (MMR) performance and iii) design of thermally coupled monolithic membrane reformer (TMMR) for vehicle. In the case of TMR and MMR, both reformers were examined by three dimensional computational fluid dynamic simulation using COMSOL Multiphysics®. Parallel arrangement and checked arrangement were considered as the flow arrangement of the reformers. The checked arrangement in TMR reduced temperature difference between cold and hot spots due to higher heat transfer. As a result, the checked arrangement is appropriate for large channel width reformer. Since the checked arrangement has larger contact area, total membrane area was utilized in MMR. Higher hydrogen permeation and lower hydrogen accumulation were observed. The parameters’ influence in TMR and MMR was reported. According to the higher performance of the checked arrangement, the arrangement was employed in the TMMR design based on a commercial monolith configuration. The TMMR was designed using Gibbs reactor and Plug flow reactor models via Aspen Plus. The efficient condition was at 4 atm and methane of 0.30 mol/s for steam reforming and 0.03 mol/s for combustion. It was found that the energy efficiency of TMMR depended on exchange area of monolith. At optimal configuration (1.5 m2 of exchange area), 200 cpsi monolith and 150 mm of diameter and length produced hydrogen equivalent to 129 kW with 43.96% efficiency. Therefore, TMMR which has 2.65 liters of volume is a potential reformer for on-board hydrogen production.
Effect of hydrogen on Ziegler - Natta catalysts prepared by different methods for ethylene polymerization
Authors:   , Niyomthai Thanyathon
Published: November 2023

This study focuses on effect of hydrogen on Ziegler-Natta (ZN) catalyst system for ethylene polymerization. The study was divided into four parts. Regarding to the first part, two types of ZN catalysts, TiCl4/MgCl2/THF (ZN-THF) and TiCl4/MgCl2•6EtOH (ZN-EtOH) catalysts, were compared. The results showed that ZN-EtOH had better active center distribution than that of ZN-THF. As a result, ZN-EtOH could retard the effect of hydrogen and showed higher activity than ZN-THF. According to higher hydrogen response of ZN-THF, ZN-THF system was selected to study in the second and the third parts with Lewis acid modification in order to improve the catalytic performance. AlCl3 and FeCl2 were employed in the second part. FeCl2 showed higher efficiency to remove the remaining THF in MgCl2 structure and provided better hydrogen response than AlCl3. For the third part, ZnCl2, mixed ZnCl2 with AlCl3 and mixed ZnCl2 with FeCl2 were studied in ZN-THF system. The results showed that ZnCl2 acted as a poison to catalyst resulting to the reduction of activity. The addition of the second Lewis acid could improve the activity; however, activity was still slightly lower than undoped ZnCl2 catalyst. For the last part, effect of alkoxysilanes as external donor on 2 types of the commercial catalysts, TiCl4/MgCl2•nEtOH and TiCl4/phthalate type/MgCl2, was investigated. Cyclohexylmethyldimethoxysilane could decrease activity more than dimethoxydimethylsilane did and provide higher hydrogen sensitivity as well.
Pervaporation-assisted enzymatic esterification of oleic acid and ethanol
Authors:   , Sumranwong Boonanun
Published: November 2023

The batch and continuous processes of enzymatic esterification of oleic acid and ethanol coupled pervaporation (PV) unit were successfully developed in this study. Bacterial cellulose (BC) impacted with alginate film was used as selectively-permeable membrane to remove water from the reaction mixture. The effects of PV operating modes, amount of enzyme (Novozym 435) loading, flow pattern in the reactor were investigated. The enzymatic esterification of oleic acid and ethanol were carried out under the operating conditions as follows: molar ratio of oleic acid to ethanol of 1:2, temperature of 45oC, turbine rate at 250 rpm, enzyme loading at 5% (w/w oleic acid) and pressure permeate side at 10 mmHg. The result shows that the BCA membrane was high selectivity to water, in which the permeate containing about 95 %(w/w) water could be removed from the reaction mixture with the water flux of 140 – 270 gm-2h-1. Considering less energy consumption, the start operation of pervaporation at the end of the reaction (late pervaporation) to move equilibrium toward biodiesel product is suggested, in which the FFA conversion was increased from 84.37 % to 88.50 % by using the system coupled with the PV unit. On the study of the flow pattern in the reactor, it was shown that the higher initial rate and FFA conversion were obtained by using the expanded bed, as compared to the fixed bed at the same reactor volume.  The evaluation of the continuous esterification process in the expanded bed reactor with the retention time of 50 min shows the improved of the FFA conversions from 65.88% to 69.73% by using the system coupled with the PV unit. From the observation of surface morphology of Novozym 435 being used in the esterification by SEM, it was demonstrated that the degrees of swelling of Novozym 435 in the batch and continuous processed coupled with pervaporation were less compared to those from the systems without the PV unit, which could be benefit for long term use of the biocatalyst.
ADSORPTION OF VOLATILE ORGANIC COMPOUNDS ON CARBON FIBER DERIVED FROM ELECTROSPUN RF-GEL
Authors:   , Pudindarn Asamaphorn
Published: November 2023

Toluene is a carcinogen and a pollutant. An adsorption using carbon fiber is a cheap and effective method in elimination of toluene. Resorcinol-formaldehyde gel (RF-gel) is a phenolic resin carbon precursor which provides carbon with outstanding properties. RF-gel fibers can be fabricated from twisted-wire needle-less electrospinning. Carbon fiber can be obtained from carbonization of RF-gel at 650, 750 and 850 ˚C. An increase in porosity of carbon fiber can be achieved from removal of disorganized carbon in pore structure via steam activation at 700, 800 and 900 ˚C for 30 minutes. Activated carbon fiber was used as an adsorbent in adsorption of toluene. An adsorption isotherm of carbon fiber shows the highest adsorption capacity up to 0.2 mg toluene/mg adsorbent. The adsorption capacity can be increased up to 0.3 mg toluene/mg adsorbent after the activation. And 1-Octanol adsorption was investigated for more detail in pore structure of carbon fiber.
Dimerization of isobutene to isooctene over NiO-WO3/Al2O3 catalysts
Authors:   , Kerdphol Kannara
Published: November 2023

NiO-WO3/Al2O3 catalysts were prepared by incipient wetness impregnation method. The catalytic performance was determined in the dimerization of isobutene under 150 ºC and atmospheric pressure. The effect of different weight percents of nickel and tungsten on the catalytic activity were investigated. The results showed that NiO-WO3/Al2O3 catalysts gave higher isobutene conversion and selectivity to isooctene than NiO/Al2O3 catalysts. Tungsten oxide increased the acidity of catalyst and improved the selectivity to isooctene. The 1Ni-4W/Al2O3 catalyst was the best ratio of nickel and tungsten that gave the highest catalytic performance. This ratio of nickel and tungsten was used in the study of different weight percents of silica in SiO2-Al2O3 supports and different preparation methods of alumina. The results in this part showed that the SiO2-Al2O3 support without metal gave higher yield to isooctene because silica-alumina possessed strong acid sites and higher total acidity of catalyst which increased the isobutene conversion. The 40SiO2-Al2O3 Al2O3 catalyst gave the highest catalytic performance. For the effect of different preparation methods of alumina including solvothermal, co-precipitation, and calcination from gibbsite, the 1Ni-4W/Al2O3-GIB catalyst gave the highest catalytic performance because calcination from gibbsite method improved the structure and acidity of catalyst that gave the high catalytic performance with low coke formation.
Ethanol dehydration over alumina catalysts with phosphorus and noble metal modification
Authors:   , Limlamthong Mutjalin
Published: November 2023

The mixture of 1:1 volume ratio of gamma and chi crystalline phase alumina support was prepared via the solvothermal technique using the mixed solution between toluene and 1-butanol. The support was brought to modify with phosphoric acid and noble metal agents. These catalysts were investigated on the effect of both phosphorus loading and types of noble metal on catalytic characteristic and catalytic activity. The catalytic performance was identified through ethanol dehydration reaction in gas phase process at 1 atm and temperature of 200oC to 400oC. The results were found that the phosphorus modification had an effect on catalytic acidity by decreasing the amount of medium to strong acid sites and raised quantity of weak acid sites. The higher amount of weak acid brought the catalysts to demonstrate the higher catalytic activity through the ethanol dehydration to diethyl ether. The mixed phase of alumina supports modified with 5 wt% of phosphorus exhibited the highest catalytic activity among other P-modified alumina catalysts giving the diethyl ether yield of 34.41%. In addition, the different types of noble metal modification were found to have a significant effect on catalytic performance. The 5P/Al2O3 catalyst deposited by palladium showed the highest catalytic activity through all of the studied catalysts reached 57.68% of diethyl ether yield. The highest average yield of diethyl ether of 42.50% was obtained from using Pd5P/Al2O3 catalyst in time on stream system for 10 h. Despite of high diethyl ether yield obtained, both 5P/Al2O3 and Pd5P/Al2O3 catalysts had the lower coke formation when compared to non-modified alumina supports.
THE EFFECT OF Pt PRECURSOR AND CALCINATION TEMPERATURE ON THE CATALYTIC PROPERTIES OF Pt/TiO2 CATALYSTS IN THE SELECTIVE HYDROGENATION OF 3-NITROSTYRENE
Authors:   , Panjamaphon Nuttaya
Published: November 2023

In this research, selective hydrogenation of 3-nitrostyrene to 3-vinylaniline which is an important intermediate for the production of pharmaceuticals, dyes, and herbicides was studied over 0.5wt%Pt/TiO2 catalysts prepared by impregnation method with various Pt precursors including H2PtCl6•6H2O, Pt(C5H7O2)2, [Pt(NH3)4]Cl2, and [Pt(NH3)4](NO3)2. The catalyst samples were calcined at different temperatures between 250-400°C. The catalytic test results in the selective hydrogenation of 3-nitrostyrene at 50°C and 2 MPa hydrogen pressure show that the catalyst prepared from Pt(NH3)4Cl4 and calcined at 350 ºC exhibited the highest conversion of 3-nirtrostyrene and the highest 3-vinylaniline selectivity at 71 and 91%, respectively after 40 min reaction time. From the H2-TPR results, it suggested that calcination at 350 ºC led to autoreduction of Pt precursors into metallic Pt particles. However, due to low CO pulse chemisorption results, it is possible that these small Pt particles were in close contract with the TiO2 supports or some Pt particles could diffuse into the TiO2 lacttice, which in good agreement with the XPS results of Ti and Pt species. Such phenomena led to promotion of the hydrogenation of nitro group, hence the catalysts exhibited high performance in term of both 3-nitostyrene conversion and 3-vinylaniline selectivity.
Synthesis of carbon nanotube/graphene hybrid material using iron oxide/graphene composite catalyst
Authors:   , Thonganantakul Oukrit
Published: November 2023

In this research, carbon nanotubes (CNTs) were synthesized on iron oxide/graphene oxide composites (Fe/GO) by chemical vapor deposition (CVD) with n-Hexane as the carbon source. The Fe/GO composites and the carbon nanotube/graphene (CNT/G) hybrid materials were characterized using FESEM, FTIR, XRD, and Raman. The effect of synthesizing temperature on the morphology and structure of products was investigated. With the synthesizing temperature varied from 700 to 800, 900 and 1000 °C, sizes of the iron oxide nanoparticles before a formation of CNTs increased from 14 to 72, 98, and 119 nm, respectively. The synthesis obtained CNTs with 20-50, 20-80, and 50-100 nm in diameter, and carbon spheres with 320-730 nm in diameter, corresponded to synthesizing temperature of 700, 800, 900, and 1000 °C, respectively. Moreover, FESEM image of CNTs synthesized over alpha iron in Fe/GO composite catalyst at 900 °C revealed the optimum temperature for CVD synthesis of CNTs. The crystallinity of CNTs from Raman spectra showed the high crystallinity than 700 and 800 °C. The degree of crystallinity (IG/ID ratio) of products synthesized at 700, 800, and 900 °C increased from 0.76, 1.45, and 1.77, respectively. In addition, the phase transformation of iron occurred completely within synthesizing temperature 1000 °C. The iron rich gamma phase in Fe/GO treated at 1000 °C was used to synthesize CNTs at 900 °C. The carbon-encapsulated iron nanoparticles was occurred over gamma iron after CVD of n-Hexane. Therefore, the formation of CNTs was required the alpha phase of iron.
Extraction of Lutein Fatty Acid Esters from Marigold Flower using Liquefied Dimethyl Ether (DME) as extractant
Authors:   , Tunyasitikun Pemika
Published: November 2023

This study will focus on the investigation of extraction of lutein fatty acid esters from marigold flowers using liquefied dimethyl ether (DME) which is nontoxic solvent as extractant. Since it is gaseous at normal temperature and pressure, DME can be easily removed from the final product by pressurizing. In this study, was divided into 3 parts. Part I involves the determination of suitable DME extraction. Effect of extraction conditions including solvent to sample ratio (w/w) and extraction temperature at 400 rpm for 30 min on extracted yield of lutein esters were investigated. The highest amount of lutein esters was found to be 20.65 mg/g dried marigold at the condition of 33:0.5 solvent to sample ratio and 35oC. The results were compared with solvent extractions using hexane as solvent and supercritical carbon dioxide extraction. Then, compared with DME extraction using wet sample with 80% and 70% moisture content. Part II deals with the determination of suitable saponification condition in order to convert the lutein esters to free lutein that was ratio of ethanol to oleoresin 20:1, 2.5% KOH concentration, 35 °C for 4 h. at such conditions, approximately 150 mg free lutein /g oleoresin was obtained. In part III, the evaluation of simultaneous DME extraction and saponification was carried out. The suitable condition for simultaneous DME extraction and saponification of lutein esters to free lutein was ratio of ethanol to dried marigold 10:0.5, 5% KOH concentration, 35 °C for 1 h. at such conditions, approximately 20.71 mg free lutein /g dried marigold was obtained. Then compared with those obtained with sequential DME extraction followed by saponification for free lutein that is 16.65 mg free lutein /g dried marigold. And also compared with simultaneous DME extraction and saponification using wet sample, at this study the amount of free lutein was 19.22 mg free lutein /g dried marigold.
Conductive patterns by spray pyrolysis ofa self-reducing copper-amine complex ink
Authors:   , Ketpokasiri Siriporn
Published: November 2023

Copper conductive films were prepared by spray pyrolysis method using copper-amine complex ink. Copper-amine ink was prepared by mixing amine solution and copper (II) formate. 0.35 M of Copper (II) formate was mixed with blend amines (diethanolamine, octylamine and dibutylamine) and 4 ml of solvent. Copper-amine complex ink was coated on PI substrate by spray pyrolysis at N2 atmosphere. The effect of types of amines and molar ratio of Cuf and amine were investigated at 200oC, 25 min. of annealing time under 6 LPM of N2 atmosphere. Moreover, the effect of spraying rate was examined by varying 0.53, 0.67 and 0.8 ml/min. The volume resistivity depends on above effect. The volume resistivity was decreased when using Cuf-DEA without alkylamine and decreasing spraying rate. The lowest resistivity of 2.691 µΩ.cm was obtained at 200 ºc using 1 Cuf : 0.12 DEA, 0.53 ml/min of spraying rate, 25 min of annealing time which is about 1.57 times higher than the resistivity of bulk copper. Moreover, the well sintered layer of the film was exhibited when decreasing spraying rate.
Operation and control of concentrated solar power system integrated with thermal energy storage system
Authors:   , Vongsilodkul Sittiporn
Published: November 2023

This research aims to study the operability and control stucture of small-scale concentrated solar power (CSP) system integrated with an organic Rankine cycle (ORC) and two different types of thermal energy storage (TES) systems: two tank and packed bed TES. The simulation was performed using a commercial steady-state simulator, PRO/II, to determine optimal operating conditions targeting at thermal efficeincy of CSP-ORC system. The solar field requires area around 75 m2 to produce energy of 18 kWh which is above an average value power comsumption in residential section. The highest thermal efficiency of 7.05% is achieved. A commercial dynamic simulator, Dynsim, is used to perform dynamic simulation in order to investigate performance of the entire processes. A modified packed bed TES is introduced for simplicity in control structure. The overall efficiency of the process is used as performance index. The index is 5.4% for two tank TES as the heat loss is neglected. In case of packed bed TES, the maximum performance index of 4.0% was achieved, hence significantly lower than two tank TES.
Fuel processor for hydrogen production via methanol steam reforming over copper-based catalysts
Authors:   , Phongboonchoo Yuththaphan
Published: November 2023

The purpose of this work is to produce high purity hydrogen stream from methanol by an integration of steam reformer and preferential oxidation of CO unit. For methanol steam reformer (MSR), Catalytic activities of Ce-Mg promoted Cu/Al₂O₃ catalysts was investigated in terms of the methanol conversion level, carbon monoxide (CO) selectivity and hydrogen (H₂) yield. It was found that the Ce-Mg bi-promoter catalysts gave a higher performance due to magnesium penetration into the cerium structure causing oxygen vacancy defects on the ceria. A face-centered central composite design response surface model was then designed to optimize the condition at a 95% conﬁdence interval revealed an optimal copper level of 46–50 wt%, Mg/(Ce+Mg) of 16.2–18.0%, temperature of 245–250 °C and S/C ratio of 1.74–1.80. In case of preferential oxidation of CO unit, catalytic activities of copper based catalysts over a series of modified ceria support was investigated in terms of the CO conversion level and carbon dioxide (CO₂) selectivity. The results revealed that the Ce-Mg support gave a higher performance due to magnesium promoted water-gas shift reaction and improved nanorods arrangement. Box-Behnken design response surface model was then designed to optimize the condition at a 95% conﬁdence interval revealed an optimal CO level of 0.65-0.75%, O₂ level of 0.80-0.90% and temperature of 130–140 °C. When integrating both MSR and PROX unit, high purity hydrogen was yielded around 45-47% without CO detected at a rate of ~120 L d⁻¹ g.cat⁻¹.
Oxidized carbon nanoparticles as drug carriers
Authors:   , Amornwachirabodee Kittima
Published: November 2023

Oxidized carbon black nanoparticles (OCBs) are successfully synthesized by modify exfoliation/oxidation process from commercially available carbon black. OCBs are 100-200 nm stable water dispersible with spherical shape. The particles contain mainly disordered π-π conjugation network of carbon atoms, with epoxide, carboxylic, and hydroxyl functionality on the surface. OCBs show no cytotoxicity against macrophage cell line (RAW 264.7), human cervical carcinoma cell line (CaSki) and keratinocyte cells, at the concentration up to 3 µg/mL, 10 µg/mL and 30 µg/mL, respectively. Experiments with cell-sized liposomes indicate that OCBs directly interact with phospholipids and induce membrane leakages. Moreover, OCBs can speed up both of micro sized and nano sized particles to association with phospholipid bilayer membranes and can increase the penetration of micro/nano particles across the membrane of the liposomes. Furthermore, experiments with cells show that OCBs can deliver a 300 kDa protein and micro/nano particles directly into cells, without an involvement of cellular endocytosis. This could be implied that the delivery by OCBs enhance the cellular penetration of bio-macromolecule and micro/nanoparticles.
Preparation of boronic acid functionalized carbon dots for glucose detection via enzymatic reaction of glucose oxidase
Authors:   , Khachonwongwattana Angkhana
Published: November 2023

In this study, novel BCDs materials were synthesized by one step hydrothermal carbonization using three isomers (ortho-, meta- and para-) of aminophenylboronic acid as a precursor for preparing the carbon dots, namely, o-BCDs, m-BCDs and p-BCDs. The morphology and structural properties of these BCDs were investigated by FT-IR, AFM, TEM, XPS techniques and 11B-NMR spectroscopy. From TEM and AFM image, the BCDs are single layer of graphene sheet and the fairly uniform of spherical quasi circular sheet. From XPS techniques and 11B-NMR spectroscopy, o-BCDs and p-BCDs have the similar component structures which is different from m-BCDs. The different structure leaded to the different emission bands of o-, m- and p-BCDs at 345 nm, 375 nm and 343 nm with quantum yield of 3.02%, 17.26% and 3.30%, respectively. Each BCDs material was applied as a fluorescent probe for H₂O₂ and glucose sensing application. For enzymatic glucose biosensor, the fluorescence quenching of BCDs depended on the concentration of H₂O₂ which was generated from enzymatic reaction by glucose and GOx. Interestingly, the m-BCDs served as an excellent fluorescent probe for glucose detection via enzymatic reaction with LOD of 0.857 mM and LOQ of 2.858 mM whereas o-BCDs and p-BCDs can detect only added H₂O₂ but H₂O₂ generated from enzymatic reaction by glucose and GOx cannot be determined.
Method development for determination of carbofuran using nanomaterial-modified screen-printed carbon electrode
Authors:   , Jirasirichote Apapond
Published: November 2023

Determination of carbofuran by differential pulse voltammetry using graphene oxide and gold nanoparticles modified screen-printed carbon electrode (AuNPs/GO-SPCE) was developed.  The optimization of the amount of graphene oxide, the concentration of gold nanoparticles and pH of supporting electrolyte were conducted by central composite design.  The characterization of the developed electrode was carried out by scanning electron microscopy and energy-dispersive X-ray spectroscopy.  Moreover, the microscopic electrode surface area and electrochemical behavior of carbofuran were studied by cyclic voltammetry.  The operational parameters including type of supporting electrolyte, accumulation time and potential, modulation time and amplitude as well as hydrolysis process of carbofuran to carbofuran-phenol were optimized.  Using differential pulse voltammetry on AuNPs/GO-SPCE under optimized conditions, the method exhibited 2 linear ranges of 1-30 (R2 = 0.9970) and 30-250 µM (R2=0.9991) with the limits of detection and quantification of 0.22 and 0.72 µM, respectively.  Interfering other effects of eight pesticides were also studied.  In addition, application of the proposed method to carbofuran determination in real cucumber and rice samples was achieved by standard addition method with acceptable recoveries of 92.8-107.2%.  This sensitive and selective carbofuran detection method is very promising for simple and inexpensive analysis of agricultural samples.
A Comparative Analysis of the Investment- and Speculative-Sovereign Credit Ratings
Authors: Lim Kok-Tiong , Goh Kim-Leng , Kwek Kian-Teng
Published: November 2023

This paper examines the variability of emphasis on sovereign credit ratings (SCRs) issued by three leading credit rating agencies: Moody’s, S&P, and Fitch. Using the sample of 55 countries with observations from year 1998 to 2017, this study reveals a clear variation of emphasis on these determinants in assessing the investment-grade versus speculative-grade rated countries. For the speculative-grade rated countries, only determinants representing the Institutional and Susceptibility to External Event factors matter during the post-global financial crisis (GFC) period. Despite the observed variabilities, there is no evidence to support the argument that the CRAs changed their criteria in SCR determination after the global financial crisis. The seven-determinant model continues to have high predictive power for SCRs of all three leading issuers in a rage of 68 to 71% for investment-grade ratings and 81 to 87% for speculative-grade ratings.
MARKET POWER AND BANKING FAILURE IN WAEMU ZONE: AN EMPIRICAL STUDY THROUGH GMM ESTIMATOR
Authors: PRAO Yao Séraphin  , BAKAYOKO Mamadou
Published: November 2023

This paper examines the relationship between market power and default risk for WAEMU banks. We use a dataset of 72 WAEMU banks from 2013 to 2020. The econometric results, after applying the system GMM estimator of Blundell and Bond (1998), indicate that bank concentration increases bank default risk. However, the test of non-linearity, through the introduction of the quadratic term of the concentration measure into the model, shows that above the 83% concentration threshold, an increase in market power could be favorable to banking stability. This study, therefore, recommends that monetary authorities exercise caution in their efforts to promote competition.