Search results for: secondary alcohol
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3749

Search results for: secondary alcohol

1769 Computer-Based versus Paper-Based Tests: A Comparative Study of Two Types of Indonesian National Examination for Senior High School Students

Authors: Faizal Mansyur

Abstract:

The objective of this research is to find out whether there is a significant difference in the English language scores of senior high school students in the Indonesia National Examination for students tested by using computer-based and paper-based tests. The population of this research is senior high school students in South Sulawesi Province who sat the Indonesian National Examination for 2015/2016 academic year. The samples of this research are 800 students’ scores from 8 schools taken by employing the multistage random sampling technique. The data of this research is a secondary data since it is obtained from the education office for South Sulawesi. In analyzing the collected data, the researcher employed the independent samples T-Test with the help of SPSS v.24 program. The finding of this research reveals that there is a significant difference in the English language scores of senior high school students in the Indonesia National Examination for students tested by using computer-based and paper-based Tests (p < .05). Moreover, students tested by using PBT (Mean = 63.13, SD = 13.63) achieve higher score than those tested by using CBT (Mean = 46.33, SD = 14.68).

Keywords: computer-based test, paper-based test, Indonesian national examination, testing

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1768 Demystifying Mathematics: Handling Learning Disabilities in Mathematics Among Low Achievers in Kenyan Schools

Authors: Gladys Gakenia Njoroge

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Mathematics is a compulsory subject in both primary and secondary schools in Kenya. However, learners’ poor performance in the subject in Kenya national examinations year in year out remains a serious concern for teachers of Mathematics, parents, curriculum developers, and the general public. This is particularly worrying because of the importance attached to the subject in national development hence the need to find out what could be affecting learning of Mathematics in Kenyan schools. The research on which this paper is based sought to examine the factors that influence performance in Mathematics in Kenyan schools; identify the characteristics of Mathematics learning disabilities; determine how the learners with such learning disabilities can be assessed and identified and interventions for these difficulties implemented. A case study was undertaken on class six learners in a primary school in Nairobi County. The tools used for the research were: classroom observations and an Individualized Education Program (IEP) developed by the teachers with the help of the researcher. This paper therefore highlights the findings from the research, discusses the implications of the findings and suggests the way forward as far as teaching, learning and assessment of Mathematics in Kenyan schools is concerned. Perhaps with the application of the right interventions, poor performance in Mathematics in the national examinations in Kenya will be a thing of the past.

Keywords: demystifying mathematics, individualized education program, learning difficulties, assessment

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1767 Potential of the Bri and the Indo-Pacific in South Asia: A Comparative Case Study

Authors: Nahian Salsabeel, Faria Leera

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—“Whoever controls the Indian Ocean, dominates Asia. This ocean is the key to the seven seas. In the 21st century, the destiny of the world will be decided on its waters” -Alfred Mahan South Asia is increasingly becoming a hub for international politics. Numerous ventures are taking place in the strategic region. Of them, the most prominent is the Belt and Road Initiative (BRI). Originating from the concept of ancient Silk Route, the Chinese Xi Jin Ping regime looks to reestablish the vast connectivity project to connect the world through infrastructure and trade. On the other hand, the US, teamed up with India, Australia and Japan, thereby forming the Quad, have launched their own foreign policy, the Indo-Pacific Strategy. The ambitious 21st century initiative for the development of maritime trade, security and governance focuses critical importance to the Indo-Pacific region, especially to South Asia. Against the backdrop of contemporary political scenario, both the Quad and China airs to establish their own footprint across the region through respective mega projects, the Indo-Pacific Strategy and the BRI. This research employs a comparative case study research method, using a secondary research design. The paper looks at the variety of opportunities and challenges posed by the BRI and the Indo Pacific, and gives the comparative study on both ends.

Keywords: BRI, Foreign Policy, Indo-Pacific, South Asia

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1766 Fulani Herdsmen and the Threat to Grassroots Security in Rural Nigeria

Authors: Akachi Odoemene

Abstract:

There is an ongoing grassroots war in Nigeria, particularly in its north central zone, as well as all through its southern parts, which have been most bloody. The war is between Fulani herdsmen and farming communities – an age-long problem which has escalated in the last decade and has assumed a very deadly dimension. In a typical scenario, Fulani herdsmen move into non-Fulani homelands with their cattle which graze on local farmlands, destroying farmers’ crops. This provokes their victims – the farmers – to acts of resistance, preventing the Fulani and their cattle from entering into farmlands. In some cases, there have been incidences of killing and/or stealing cattle, or poisoning of fields. In response, the herders wedge deadly attacks on farming communities, leading to the death of thousands of people. To be sure, this has been a major factor of instability in the rural areas of Nigeria. This paper aims at engaging the issues and cross-cutting issues of interest, as well as providing context and perspectives to the violent conflicts between Fulani herders and local communities in Nigeria. It particularly interrogates four central issues: (1) the nature and dynamics of the crisis, (2) the positions and stakes of the parties to the crisis, (3) the remedies available for containing/managing the conflicts and their desirability, and (4) perspectives on the positions of government(s) (and the African Union) on this conflict. Both primary and secondary sources were used for the purposes of this essay.

Keywords: Fulani Herdsmen, violent conflicts and insecurity, sustainable remedies, Nigeria

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1765 Methods of Detoxification of Nuts With Aflatoxin B1 Contamination

Authors: Auteleyeva Laura, Maikanov Balgabai, Smagulova Ayana

Abstract:

In order to find and select detoxification methods, patent and information research was conducted, as a result of which 68 patents for inventions were found, among them from the near abroad - 14 (Russia), from far abroad: China – 27, USA - 6, South Korea–1, Germany - 2, Mexico – 4, Yugoslavia – 7, Austria, Taiwan, Belarus, Denmark, Italy, Japan, Canada for 1 security document. Aflatoxin B₁ in various nuts was determined by two methods: enzyme immunoassay "RIDASCREEN ® FAST Aflatoxin" with determination of optical density on a microplate spectrophotometer RIDA®ABSORPTION 96 with RIDASOFT® software Win.NET (Germany) and the method of high-performance liquid chromatography (HPLC Corporation Water, USA) according to GOST 307112001. For experimental contamination of nuts, the cultivation of strain A was carried out. flavus KWIK-STIK on the medium of Chapek (France) with subsequent infection of various nuts (peanuts, peanuts with shells, badam, walnuts with and without shells, pistachios).Based on our research, we have selected 2 detoxification methods: method 1 – combined (5% citric acid solution + microwave for 640 W for 3 min + UV for 20 min) and a chemical method with various leaves of plants: Artemisia terra-albae, Thymus vulgaris, Callogonum affilium, collected in the territory of Akmola region (Artemisia terra-albae, Thymus vulgaris) and Western Kazakhstan (Callogonum affilium). The first stage was the production of ethanol extracts of Artemisia terraea-albae, Thymus vulgaris, Callogonum affilium. To obtain them, 100 g of vegetable raw materials were taken, which was dissolved in 70% ethyl alcohol. Extraction was carried out for 2 hours at the boiling point of the solvent with a reverse refrigerator using an ultrasonic bath "Sapphire". The obtained extracts were evaporated on a rotary evaporator IKA RV 10. At the second stage, the three samples obtained were tested for antimicrobial and antifungal activity. Extracts of Thymus vulgaris and Callogonum affilium showed high antimicrobial and antifungal activity. Artemisia terraea-albae extract showed high antimicrobial activity and low antifungal activity. When testing method 1, it was found that in the first and third experimental groups there was a decrease in the concentration of aflatoxin B1 in walnut samples by 63 and 65%, respectively, but these values also exceeded the maximum permissible concentrations, while the nuts in the second and third experimental groups had a tart lemon flavor; When testing method 2, a decrease in the concentration of aflatoxin B1 to a safe level was observed by 91% (0.0038 mg/kg) in nuts of the 1st and 2nd experimental groups (Artemisia terra-albae, Thymus vulgaris), while in samples of the 2nd and 3rd experimental groups, a decrease in the amount of aflatoxin in 1 to a safe level was observed.

Keywords: nuts, aflatoxin B1, my, mycotoxins

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1764 Oxidative Stability of Corn Oil Supplemented with Natural Antioxidants from Cypriot Salvia fruticosa Extracts

Authors: Zoi Konsoula

Abstract:

Vegetable oils, which are rich in polyunsaturated fatty acids, are susceptible to oxidative deterioration. The lipid oxidation of oils results in the production of rancid odors and unpleasant flavors as well as the reduction of their nutritional quality and safety. Traditionally, synthetic antioxidants are employed for their retardation or prevention of oxidative deterioration of oils. However, these compounds are suspected to pose health hazards. Consequently, recently there has been a growing interest in the use of natural antioxidants of plant origin for improving the oxidative stability of vegetable oils. The genus Salvia (sage) is well known for its antioxidant activity. In the Cypriot flora Salvia fruticosa is the most distributed indigenous Salvia species. In the present study, extracts were prepared from S. fruticosa aerial parts using various solvents and their antioxidant activity was evaluated by the 1,1-diphenyl-2-picrylhydrazine (DPPH) radical scavenging and Ferric Reducing Antioxidant Power (FRAP) method. Moreover, the antioxidant efficacy of all extracts was assessed using corn oil as the oxidation substrate, which was subjected to accelerated aging (60 °C, 30 days). The progress of lipid oxidation was monitored by the determination of the peroxide, p-aniside, conjugated dienes and trienes value according to the official AOCS methods. Synthetic antioxidants (butylated hydroxytoluene-BHT and butylated hydroxyanisole-BHA) were employed at their legal limit (200 ppm) as reference. Finally, the total phenolic (TPC) and flavonoid content (TFC) of the prepared extracts was measured by the Folin-Ciocalteu and aluminum-flavonoid complex method, respectively. The results of the present study revealed that although all sage extracts prepared from S. fruticosa exhibited antioxidant activity, the highest antioxidant capacity was recorded in the methanolic extract, followed by the non-toxic, food grade ethanol. Furthermore, a positive correlation between the antioxidant potency and the TPC of extracts was observed in all cases. Interestingly, sage extracts prevented lipid oxidation in corn oil at all concentrations tested, however, the magnitude of stabilization was dose dependent. More specifically, results from the different oxidation parameters were in agreement with each other and indicated that the protection offered by the various extracts depended on their TPC. Among the extracts, the methanolic extract was more potent in inhibiting oxidative deterioration. Finally, both methanolic and ethanolic sage extracts at a concentration of 1000 ppm exerted a stabilizing effect comparable to that of the reference synthetic antioxidants. Based on the results of the present study, sage extracts could be used for minimizing or preventing lipid oxidation in oils and, thus, prolonging their shelf-life. In particular, given that the use of dietary alcohol, such as ethanol, is preferable than methanol in food applications, the ethanolic extract prepared from S. fruticosa could be used as an alternative natural antioxidant.

Keywords: antioxidant activity, corn oil, oxidative deterioration, sage

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1763 Investigation Studies of WNbMoVTa and WNbMoVTaCr₀.₅Al Refractory High Entropy Alloys as Plasma-Facing Materials

Authors: Burçak Boztemur, Yue Xu, Laima Luo, M. Lütfi Öveçoğlu, Duygu Ağaoğulları

Abstract:

Tungsten (W) is used chiefly as plasma-facing material. However, it has some problems, such as brittleness after plasma exposure. High-entropy alloys (RHEAs) are a new opportunity for this deficiency. So, the neutron shielding behavior of WNbMoVTa and WNbMoVTaCr₀.₅Al compositions were examined against He⁺ irradiation in this study. The mechanical and irradiation properties of the WNbMoVTa base composition were investigated by adding the Al and Cr elements. The mechanical alloying (MA) for 6 hours was applied to obtain RHEA powders. According to the X-ray diffraction (XRD) method, the body-centered cubic (BCC) phase and NbTa phase with a small amount of WC impurity that comes from vials and balls were determined after 6 h MA. Also, RHEA powders were consolidated with the spark plasma sintering (SPS) method (1500 ºC, 30 MPa, and 10 min). After the SPS method, (Nb,Ta)C and W₂C₀.₈₅ phases were obtained with the decomposition of WC and stearic acid that is added during MA based on XRD results. Also, the BCC phase was obtained for both samples. While the Al₂O₃ phase with a small intensity was seen for the WNbMoVTaCr₀.₅Al sample, the Ta₂VO₆ phase was determined for the base sample. These phases were observed as three different regions according to scanning electron microscopy (SEM). All elements were distributed homogeneously on the white region by measuring an electron probe micro-analyzer (EPMA) coupled with a wavelength dispersive spectroscope (WDS). Also, the grey region of the WNbMoVTa sample was rich in Ta, V, and O elements. However, the amount of Al and O elements was higher for the grey region of the WNbMoVTaCr₀.₅Al sample. The high amount of Nb, Ta, and C elements were determined for both samples. Archimedes’ densities that were measured with alcohol media were closer to the theoretical densities of RHEAs. These values were important for the microhardness and irradiation resistance of compositions. While the Vickers microhardness value of the WNbMoVTa sample was measured as ~11 GPa, this value increased to nearly 13 GPa with the WNbMoVTaCr₀.₅Al sample. These values were compatible with the wear behavior. The wear volume loss was decreased to 0.16×10⁻⁴ from 1.25×10⁻⁴ mm³ by the addition of Al and Cr elements to the WNbMoVTa. The He⁺ irradiation was conducted on the samples to observe surface damage. After irradiation, the XRD patterns were shifted to the left because of defects and dislocations. He⁺ ions were infused under the surface, so they created the lattice expansion. The peak shifting of the WNbMoVTaCr₀.₅Al sample was less than the WNbMoVTa base sample, thanks to less impact. A small amount of fuzz was observed for the base sample. This structure was removed and transformed into a wavy structure with the addition of Cr and Al elements. Also, the deformation hardening was actualized after irradiation. A lower amount of hardening was obtained with the WNbMoVTaCr₀.₅Al sample based on the changing microhardness values. The surface deformation was decreased in the WNbMoVTaCr₀.₅Al sample.

Keywords: refractory high entropy alloy, microhardness, wear resistance, He⁺ irradiation

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1762 The Relationship between Osteoporosis-Related Knowledge and Physical Activity among Women Age over 50 Years

Authors: P. Tardi, B. Szilagyi, A. Makai, P. Acs, M. Hock, M. Jaromi

Abstract:

Osteoporosis is becoming a major public health problem, particularly in postmenopausal women, as the incidence of this disease is getting higher. Nowadays, one of the most common chronic musculoskeletal diseases is osteoporosis. Osteoporosis-related knowledge is an important contributor to prevent or to treat osteoporosis. The most important strategies to prevent or treat the disease are increasing the level of physical activity at all ages, cessation of smoking, reduction of alcohol consumption, adequate dietary calcium, and vitamin D intake. The aim of the study was to measure the osteoporosis-related knowledge and physical activity among women age over 50 years. For the measurements, we used the osteoporosis questionnaire (OPQ) to examine the disease-specific knowledge and the global physical activity questionnaire (GPAQ) to measure the quantity and quality of the physical activity. The OPQ is a self-administered 20-item questionnaire with five categories: general information, risk factors, investigations, consequences, and treatment. There are four choices per question (one of them is the 'I do not know'). The filler gets +1 for a good answer, -1 point for a bad answer, and 0 for 'I do not know' answer. We contacted with 326 women (63.08 ± 9.36 year) to fill out the questionnaires. Descriptive analysis was carried out, and we calculated Spearman's correlation coefficient to examine the relationship between the variables. Data were entered into Microsoft Excel, and all statistical analyses were performed using SPSS (Version 24). The participants of the study (n=326) reached 8.76 ± 6.94 points on OPQ. Significant (p < 0.001) differences were found in the results of OPQ according to the highest level of education. It was observed that the score of the participants with osteoporosis (10.07 ± 6.82 points) was significantly (p=0.003) higher than participants without osteoporosis (9.38 ± 6.66 points) and the score of those women (6.49 ± 6.97 points) who did not know that osteoporosis exists in their case. The GPAQ results showed the sample physical activity in the dimensions of vigorous work (479.86 ± 684.02 min/week); moderate work (678.16 ± 804.5 min/week); travel (262.83 ± 380.27 min/week); vigorous recreation (77.71 ± 123.46 min/week); moderate recreation (115.15 ± 154.82 min/week) and total weekly physical activity (1645.99 ± 1432.88 min/week). Significant correlations were found between the osteoporosis-related knowledge and the physical activity in travel (R=0.21; p < 0.001), vigorous recreation (R=0.35; p < 0.001), moderate recreation (R=0.35; p < 0.001), total vigorous minutes/week (R=0.15; p=0.001) and total moderate minutes/week (R=0.13; p=0.04) dimensions. According to the results that were achieved, the highest level of education significantly determines osteoporosis-related knowledge. Physical activity is an important contributor to prevent or to treat osteoporosis, and it showed a significant correlation with osteoporosis-related knowledge. Based on the results, the development of osteoporosis-related knowledge may help to improve the level of physical activity, especially recreation. Acknowledgment: Supported by the ÚNKP-20-1 New National Excellence Program of The Ministry for Innovation and Technology from the Source of the National Research, Development and Innovation Fund.

Keywords: osteoporosis, osteoporosis-related knowledge, physical activity, prevention

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1761 Synthesis of Flavonoid Derivatives Precursors of Active Pharmaceutical Ingredients by Mechanical Chemistry

Authors: Imen Abid, Rachel Calvet, Michel Baltas

Abstract:

Flavonoids are secondary metabolites that belong to a polyphenolic class, present in fruits and vegetables, playing a significant role in biological systems. The structural variations of these flavonoids are associated with many biological and pharmacological activities (antioxidant, anti-inflammatory, anticancer, antibacterial, antifungal, antiviral, and antimalarial). Given their importance in plants and health-promoting roles in humans, significant efforts have been devoted towards their isolation of flavonoids and chemical elaboration (organic synthesis). But with the increasing public concern over environmental degradation and future resources, it is of great importance for chemists to come up with different approaches, less hazardous to human health and the environment. Being employed in large amounts, the solvents used in organic synthesis are high on the list of environmental pollutants. To overcome these problems, our approach is to develop unconventional processes involving solvent-free conditions. The application of mechanical forces to solvent-free or solvent-less reaction mixtures through the use of ball mills offers many advantages over traditional solvent-based strategies. It is one of the unconventional activation methods, which makes it possible to overcome the use of solvents, in the context of green chemistry and more respectful of the environment.

Keywords: organic synthesis, green chemistry, mecanochemistry, pharmaceutical molecules

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1760 Potential Use of Spore-Forming Biosurfactant Producing Bacteria in Oil-Pollution Bioremediation

Authors: S. N. Al-Bahry, Y. M. Al-Wahaibi, S. J. Joshi, E. A. Elshafie, A. S. Al-Bimani

Abstract:

Oman is one of the oil producing countries in the Arabian Peninsula and the Gulf region. About 30-40 % of oil produced from the Gulf is transported globally along the seacoast of Oman. Oil pollution from normal tanker operations, ballast water, illegal discharges and accidental spills are always serious threats to terrestrial and marine habitats. Due to Oman’s geographical location at arid region where the temperature ranges between high 40s and low 50s Celsius in summers with low annual rainfall, the main source of fresh water is desalinated sea and brackish water. Oil pollution, therefore, pose a major threat to drinking water. Biosurfactants are secondary metabolites produced by microorganisms in hydrophobic environments to release nutrients from solid surfaces, such as oil. In this study, indigenous oil degrading thermophilic spore forming bacteria were isolated from oil fields contaminated soil. The isolates were identified using MALDI-TOF biotyper and 16s RNA. Their growth conditions were optimized for the production of biosurfactant. Surface tension, interfacial tensions and microbial oil biodegradation capabilities were tested. Some thermophilic bacteria degraded either completely or partially heavy crude oil (API 10-15) within 48h suggesting their high potential in oil spill bioremediation and avoiding the commonly used physical and chemical methods which usually lead to other environmental pollution.

Keywords: bacteria, bioremediation, biosurfactant, crude-oil-pollution

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1759 Analysis of Linguistic Disfluencies in Bilingual Children’s Discourse

Authors: Sheena Christabel Pravin, M. Palanivelan

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Speech disfluencies are common in spontaneous speech. The primary purpose of this study was to distinguish linguistic disfluencies from stuttering disfluencies in bilingual Tamil–English (TE) speaking children. The secondary purpose was to determine whether their disfluencies are mediated by native language dominance and/or on an early onset of developmental stuttering at childhood. A detailed study was carried out to identify the prosodic and acoustic features that uniquely represent the disfluent regions of speech. This paper focuses on statistical modeling of repetitions, prolongations, pauses and interjections in the speech corpus encompassing bilingual spontaneous utterances from school going children – English and Tamil. Two classifiers including Hidden Markov Models (HMM) and the Multilayer Perceptron (MLP), which is a class of feed-forward artificial neural network, were compared in the classification of disfluencies. The results of the classifiers document the patterns of disfluency in spontaneous speech samples of school-aged children to distinguish between Children Who Stutter (CWS) and Children with Language Impairment CLI). The ability of the models in classifying the disfluencies was measured in terms of F-measure, Recall, and Precision.

Keywords: bi-lingual, children who stutter, children with language impairment, hidden markov models, multi-layer perceptron, linguistic disfluencies, stuttering disfluencies

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1758 Study of Some Biological Profiles as Limiting Factors of Male Fertility in the Region of Batna, Algeria

Authors: Bousnane Nour El Houda, Chennaf Ali, Yahia Mouloud, Benbia Souhila

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Male infertility or the inability of a man to procreate is a major public health problem, where it is a leading cause of marital discord in several countries such Algeria. The objective of this work is to study some biological profiles of infertile men from the city of Batna/Algeria and to identify the causes of infertility in a population of infertile males to improve its management and to establish a good therapeutic strategy through a study that lasted 10 months in the Department of Urology of the University Hospital of Banta and on a population of 140 infertile subjects. For every man, series of assessments was performed to determine the exact causes of infertility. We found 102 cases of primary infertility against 38 cases of secondary infertility; the average age of men was 39.7 years, with a predominance of the age group (46-50 years). 34.29% of subjects had genital infections against 17.14% with varicocele. 132 men presented spermiologiques abnormalities; a asthénospermie (AS) in 27.27% of the cases, astheno-terato spermiea (OATS) 11.36% while Azoospermes showed 5.07%. Genital infections are the main causes of infertility (34.29%) of the cases. The results of spermocytogramme showed a predominance of head abnormalities (41.70%), while the flagellum abnormalities presented 33.83%. The dosage of the seminal plasma carnitine showed no pathological cases, which makes it difficult to know their association with infertility. By against some disturbances Fructose and Zinc have been reported.

Keywords: male infertility, spermogramme, spermocytogramme, biological profils

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1757 Strategic Fit between Higher Education Funding and the National Development Goals in Kazakhstan

Authors: Ali Ait Si Mhamed, Rita Kasa, Hans Vossensteyn

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Kazakhstan is the eight largest country on the globe, in terms of the territory, it is rich in natural resources and is developing dynamically. Kazakhstan strives to become one of the top 30 global economies by 2050. This goal preconditions intensive reforms in all sectors of economy, including higher education. This paper focuses on the higher education funding reforms that take place in Kazakhstan and their alignment with the strategic goals of national development. Currently, the government funds higher education costs for only a limited number of students while the majority of students pay full cost covering tuition fees. Only students with high examination scores at the end of the secondary education are eligible to be admitted to publically funded study places in higher education. While this merit-based higher education funding model is overall well-received in the country, there is also a discourse calling to change the existing approach of higher education funding. This paper draws on interviews with national policy makers and leadership at institutions of higher education in Kazakhstan collected during 2016. It seeks to answer a question about how well the current higher education funding mechanism is aligned with the strategic development goals in higher education. The paper discusses how stakeholders see the fit between the current higher education funding mechanism and the ability of higher education institutions to achieve the aims of national strategic development.

Keywords: higher education reform, higher education funding, higher education policy, Kazakhstan

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1756 Dynamics of Norms and Identities Facilitate Countries to Resolve Their Conflicts: A Case Study of ASEAN

Authors: Chander Shekhar Kohli

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In the field of international relations, countries have been experiencing distinct nature of conflicts. But, in the case of Association of Southeast Asian Nations (ASEAN) for a long time, the members have witnessed conflicts, small and large. These conflicts, as a result, have given catastrophic outcomes, such as killings and destroying properties. For the resolution of such conflicts, nonetheless, efforts likewise have been made, simultaneously, in terms of establishing peace and security. In this background, the ASEAN presents a significant example as before it had faced several wars, like Vietnam War, Cambodia conflicts, and so on. This research paper, therefore, strives to examine the ASEAN as a case with the help of both primary and secondary sources. It likewise will be dealt with how changing norms and identity building facilitate the ASEAN countries to deal with their conflicts both internal and external. This paper also will discuss how internal developments within countries affect conflict resolution process as each member of ASEAN is guided by its national interest. It is then argued that conflict resolution in the ASEAN is moving from its existing power-based solution to norms and identity-based solution as member countries have become more dependent on other countries. The research, therefore, is concluded by saying that the conflicts could only be resolved through building norms and common identities, which of course are recognized crucial mechanisms among the ASEAN countries with some exceptions.

Keywords: ASEAN, conflict resolution, norms and identities, peace and security

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1755 Using Presentation as a Means to Develop Communication Skills of Engineering Students

Authors: Urvashi Kaushal

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With the entry of multinationals in India, engineering students of Indian universities have opportunity to work with the best and the most innovative industries in the world, but in order to compete in the global job market, they require an added competence of communication skills in English. With work places turning global, competence in English can provide the Indian student the added advantage to begin his/her career in the international market. The present method of teaching English in any engineering college across Gujarat mostly concentrates on developing writing, and reading skills. Developing speech becomes a secondary topic owing to the old trend of lecturing in the class room and the huge strength of the class. This paper aims to highlight the importance of improving speaking skills of engineering students. It also insists that presentations can be used as a viable method to enhance the communication skills of these students. Presentations force students to plan, prepare, practice and perfect their communication skills which will enable them to get a foothold in the industry. The paper also discusses one such experiment carried out at the author’s institute and the response it received. Further, such experimental language learning approach is bound to have some limitations and obstacles. The paper suggests ways to overcome such limitations and strives to develop an interesting means of developing communication skills of the engineering students.

Keywords: engineering, English, presentation, communication skills

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1754 Impact of Natural Degradation of Low Density Polyethylene on Its Morphology

Authors: Meryem Imane Babaghayou, Asma Abdelhafidi, Salem Fouad Chabira, Mohammed Sebaa

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A challenge of plastics industries is the realization of materials that resist the degradation in its application environment, and that to guarantee a longer life time therefore an optimal time of use. Blown extruded films of low-density polyethylene (LDPE) supplied by SABIC SAUDI ARABIA blown and extruded in SOFIPLAST company in Setif ALGERIA , have been subjected to climatic ageing in a sub-Saharan facility at Laghouat (Algeria) with direct exposure to sun. Samples were characterized by X-ray diffraction (XRD) and differential scanning calorimetry (DSC) techniques after prescribed amounts of time up to 8 months. It has been shown via these two techniques the impact of UV irradiation on the morphological development of a plastic material, especially the crystallinity degree which increases with exposure time. The reason of these morphological changes is related to photooxidative reactions leading to cross linking in the beginning and to chain scissions for an advanced stage of ageing this last ones are the first responsible. The crystallinity degree change is essentially controlled by the secondary crystallization of the amorphous chains whose mobility is enhanced by the chain scission processes. The diffusion of these short segments integrates the surface of the lamellae increasing in this way their thicknesses. The results presented highlight the complexity of the involved phenomena.

Keywords: Low Density poly (Ethylene), crystallinity, ageing, XRD, DSC

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1753 Utilizing Fly Ash Cenosphere and Aerogel for Lightweight Thermal Insulating Cement-Based Composites

Authors: Asad Hanif, Pavithra Parthasarathy, Zongjin Li

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Thermal insulating composites help to reduce the total power consumption in a building by creating a barrier between external and internal environment. Such composites can be used in the roofing tiles or wall panels for exterior surfaces. This study purposes to develop lightweight cement-based composites for thermal insulating applications. Waste materials like silica fume (an industrial by-product) and fly ash cenosphere (FAC) (hollow micro-spherical shells obtained as a waste residue from coal fired power plants) were used as partial replacement of cement and lightweight filler, respectively. Moreover, aerogel, a nano-porous material made of silica, was also used in different dosages for improved thermal insulating behavior, while poly vinyl alcohol (PVA) fibers were added for enhanced toughness. The raw materials including binders and fillers were characterized by X-Ray Diffraction (XRD), X-Ray Fluorescence spectroscopy (XRF), and Brunauer–Emmett–Teller (BET) analysis techniques in which various physical and chemical properties of the raw materials were evaluated like specific surface area, chemical composition (oxide form), and pore size distribution (if any). Ultra-lightweight cementitious composites were developed by varying the amounts of FAC and aerogel with 28-day unit weight ranging from 1551.28 kg/m3 to 1027.85 kg/m3. Excellent mechanical and thermal insulating properties of the resulting composites were obtained ranging from 53.62 MPa to 8.66 MPa compressive strength, 9.77 MPa to 3.98 MPa flexural strength, and 0.3025 W/m-K to 0.2009 W/m-K as thermal conductivity coefficient (QTM-500). The composites were also tested for peak temperature difference between outer and inner surfaces when subjected to heating (in a specially designed experimental set-up) by a 275W infrared lamp. The temperature difference up to 16.78 oC was achieved, which indicated outstanding properties of the developed composites to act as a thermal barrier for building envelopes. Microstructural studies were carried out by Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS) for characterizing the inner structure of the composite specimen. Also, the hydration products were quantified using the surface area mapping and line scale technique in EDS. The microstructural analyses indicated excellent bonding of FAC and aerogel in the cementitious system. Also, selective reactivity of FAC was ascertained from the SEM imagery where the partially consumed FAC shells were observed. All in all, the lightweight fillers, FAC, and aerogel helped to produce the lightweight composites due to their physical characteristics, while exceptional mechanical properties, owing to FAC partial reactivity, were achieved.

Keywords: aerogel, cement-based, composite, fly ash cenosphere, lightweight, sustainable development, thermal conductivity

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1752 A Historo-Religious Approach to Christian-Muslim Relations in Nasarawa State, Nigeria.

Authors: Akolo Ajige

Abstract:

Christian-Muslim relations had been existing for a long time in Nigeria. Despite the long standing relations between the two faith communities, there had been occasional religious crises in Nigeria (especially in Northern part of Nigeria). These crises have rendered some people homeless, left some without a family, while property worth millions of naira destroyed, and thereby putting some people in perpetual trauma. The situation seemed to be entirely different in Nasarawa State where there is relative peace between Christians and Muslims. The purpose of the study therefore was to examine Christian-Muslim relations in Nasarawa State. Its objectives were to: (i) identify the factors responsible for the peaceful coexistence between Christians and Muslims in Nasarawa State; (ii) state how they were relating in times of politics, worship, celebration of religious festivals etc; (iii) discuss how issues which could have led to crises were resolved between the two faiths, and (iv) examine the roles played by the religious leaders, traditional rulers and the media on peaceful co-existence between the Muslims and the Christians in Nasarawa State. Historical and Comparative methods were adopted in this research. Historical method helped to evaluate the history of Islam and Christianity in Nasarawa State, while comparative method was adopted to assess the extent of interaction of Muslims and Christians in the State. The study employed primary and secondary sources as tools for gathering information.

Keywords: historo-religious, christian, muslim, relations

Procedia PDF Downloads 41
1751 Design Intelligence in Garment Design Between Technical Creativity and Artistic Creativity

Authors: Kanwar Varinder Pal Singh

Abstract:

Art is one of the five secondary sciences next to the social sciences. As per the single essential concept in garment design, it is the coexistence and co-creation of two aspects of reality: Ultimate reality and apparent or conventional reality. All phenomena possess two natures: That which is revealed by correct perception and that which is induced by deceptive perception. The object of correct perception is the ultimate reality, the object of deceptive perception is conventional reality. The same phenomenon, therefore, may be perceived according to its ultimate nature or its apparent nature. Ultimate reality is also called ‘emptiness’. Emptiness does not mean that all phenomena are nothing but do not exist in themselves. Although phenomena, the universe, thoughts, beings, time, and so on, seem very real in themselves, ultimately, they are not. Each one of us can perceive the changing and unpredictable nature of existence. This transitory nature of phenomena, impermanence, is the first sign of emptiness. Sometimes, the interdependence of phenomena leads to ultimate reality, which is nothing but emptiness, e.g., a rainbow, which is an effect due to the function of ‘sun rays,’ ‘rain,’ and ‘time.’ In light of the above, to achieve decision-making for the global desirability of garment design, the coexistence of artistic and technical creativity must achieve an object of correct perception, i.e., ultimate reality. This paper mentions the decision-making technique as semiotic engineering, both subjective and objective.

Keywords: global desirability, social desirability, comfort desirability, handle desirability, overall desirability

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1750 Systematic Study of Mutually Inclusive Influence of Temperature and Substitution on the Coordination Geometry of Co(II) in a Series of Coordination Polymer and Their Properties

Authors: Manasi Roy, Raju Mondal

Abstract:

During last two decades the synthesis and design of MOFs or novel coordination polymers (CPs) has flourished as an emerging area of research due to their role as functional materials. Accordingly, ten new cobalt-based MOFs have been synthesized using a simple bispyrazole ligand, 4,4′-methylene-bispyrazole (H2MBP), and isophthalic acid (H2IPA) and its four 5-substituted derivatives R-H2IPA (R = COOH, OH, tBu, NH2). The major aim of this study was to validate the mutual influence of temperature and substitutions on the final structural self-assembly. Five different isophthalic acid derivatives were used to study the influence of substituents while each reaction was carried out at two different temperatures to assess the temperature effect. A clear correlation was observed between the reaction temperature and the coordination number of the cobalt atoms which consequently changes the self assembly pattern. Another fact that the periodical change in coordination number did bring about some systematic changes in the structural network via secondary building unit selectivity. With the presence of a tunable cavity inside the network, and unsaturated metal centers, MOFs show highly encouraging photocatalytic degradation of toxic dye with a potential application in waste water purification. Another fascinating aspect of this work is the construction of magnetic coordination polymers with the occurrence of a not-so-common MCE behavior of cobalt-based MOF.

Keywords: MOFs, temperature effect, MCE, dye degradation

Procedia PDF Downloads 132
1749 Addressing Sexual Health in Males with Spinal Cord Injury in Rural South India: Using the Knowledge to Action Framework to Evaluate an Education Manual on Improving Knowledge, Attitudes and Practices

Authors: Cassandra Maffei, Effie Pomaki, Salomé Deslauriers-Brouillard, Levana Dahan, Caroline Storr, Ramasubramanian Ponnusamy, Philippe S. Archambault

Abstract:

Sexual health education following spinal cord injury (SCI) remains poorly integrated into the rehabilitation process, especially in low-income countries where the topics of disability and sexuality are stigmatized. This research aimed to evaluate a sexual health manual that was created and distributed amongst males with SCI who had received rehabilitation services at Amar Seva Sangam (ASSA), a rehabilitation center located in rural South India. A service evaluation was completed to collect data from a convenience sample of 37 males with spinal cord injuries. Data were analyzed using descriptive statistics and content analysis. The service evaluation showed that the manual was well received by the sample and had positive impacts on secondary outcome measures, including relationship dynamics and quality of life. It can thus be used as an effective adjunct tool to support the improvement of sexual health knowledge, attitudes, and practices of individuals with SCI.

Keywords: spinal cord injury, sexual health, rehabilitation, India, education, service evaluation

Procedia PDF Downloads 93
1748 Quality of Life of Patients on Oral Antiplatelet Therapy in Outpatient Cardiac Department Dr. Hasan Sadikin Central General Hospital Bandung

Authors: Andhiani Sharfina Arnellya, Mochammad Indra Permana, Dika Pramita Destiani, Ellin Febrina

Abstract:

Health Research Data, Ministry of Health of Indonesia in 2007, showed coronary heart disease (CHD) or coronary artery disease (CAD) was the third leading cause of death in Indonesia after hypertension and stroke with 7.2% incidence rate. Antiplatelet is one of the important therapy in management of patients with CHD. In addition to therapeutic effect on patients, quality of life is one aspect of another assessment to see the success of antiplatelet therapy. The purpose of this study was to determine the quality of life of patients on oral antiplatelet therapy in outpatient cardiac department Dr. Hasan Sadikin central general hospital, Bandung, Indonesia. This research is a cross sectional by collecting data through quality of life questionnaire of patients which performed prospectively as primary data and secondary data from medical record of patients. The results of this study showed that 54.3% of patients had a good quality of life, 45% had a moderate quality of life, and 0.7% had a poor quality of life. There are no significant differences in quality of life-based on age, gender, diagnosis, and duration of drug use.

Keywords: antiplatelet, quality of life, coronary artery disease, coronary heart disease

Procedia PDF Downloads 322
1747 Careers-Outreach Programmes for Children: Lessons for Perceptions of Engineering and Manufacturing

Authors: Niall J. English, Sylvia Leatham, Maria Isabel Meza Silva, Denis P. Dowling

Abstract:

The training and education of under- and post-graduate students can be promoted by more active learning especially in engineering, overcoming more passive and vicarious experiences and approaches in their documented effectiveness. However, the possibility of outreach to young pupils and school-children in primary and secondary schools is a lesser explored area in terms of Education and Public Engagement (EPE) efforts – as relates to feedback and influence on shaping 3rd-level engineering training and education. Therefore, the outreach and school-visit agenda constitutes an interesting avenue to observe how active learning, careers stimulus and EPE efforts for young children and teenagers can teach the university sector, to improve future engineering-teaching standards and enhance both quality and capabilities of practice. This intervention involved careers-outreach efforts to lead to statistical determinations of motivations towards engineering, manufacturing and training. The aim was to gauge to what extent this intervention would lead to an increased careers awareness in engineering, using the method of the schools-visits programme as the means for so doing. It was found that this led to an increase in engagement by school pupils with engineering as a career option and a greater awareness of the importance of manufacturing.

Keywords: outreach, education and public engagement, careers, peer interactions

Procedia PDF Downloads 151
1746 An Experimental Approach of the Reuse of Dredged Sediments in a Cement Matrix by Physical and Heat Treatment

Authors: Mahfoud Benzerzour, Mouhamadou Amar, Nor-edine Abriak

Abstract:

In this study, a sediment was used as a secondary raw material in cement substitution with prior treatment. The treatment adopted is a physical treatment involving grinding and separation to obtain different fractions, using a dry method (1 mm, 250µm, 120µm) and washing method (250µm and 120µm). They were subsequently heat treated at temperatures of 650°C, 750°C and 850°C for 1 hour and 3 hours, in order to enable chemical activation by decarbonation or by pozzolanic activation of the material. Different characterization techniques were performed. The determination of main physical and chemical characteristics was obtained through multiple tests: particle size distribution, specific density, the BET surface area, the initial setting time and hydration heat calorimetry Langavant. The chemical tests include: ATG analysis, X-ray diffractometry (XRD) and X-ray fluorescence (XRF) which were used to quantify the fractions, phases and chemical elements present. Compression tests were performed conforming NF EN 196-1 French standard, over terms of 7 days - 14 days - 28 days and 60 days on all formulated mortars: reference mortar based on 100% CEM I 52.5N binder and cement substituted mortars with 8% and 15% by treated sediment. This clearly evidenced contribution due to the chemical activity which was confirmed by calorimetry monitoring and strength investigation.

Keywords: sediment, characterization, grinding, heat treatment, substitution

Procedia PDF Downloads 201
1745 Judicial Analysis of the Burden of Proof on the Perpetrator of Corruption Criminal Act

Authors: Rahmayanti, Theresia Simatupang, Ronald H. Sianturi

Abstract:

Corruption criminal act develops rapidly since in the transition era there is weakness in law. Consequently, there is an opportunity for a few people to do fraud and illegal acts and to misuse their positions and formal functions in order to make them rich, and the criminal acts are done systematically and sophisticatedly. Some people believe that legal provisions which specifically regulate the corruption criminal act; namely, Law No. 31/1999 in conjunction with Law No. 20/2001 on the Eradication of Corruption Criminal Act are not effective any more, especially in onus probandi (the burden of proof) on corruptors. The research was a descriptive analysis, a research method which is used to obtain description on a certain situation or condition by explaining the data, and the conclusion is drawn through some analyses. The research used judicial normative approach since it used secondary data as the main data by conducting library research. The system of the burden of proof, which follows the principles of reversal of the burden of proof stipulated in Article 12B, paragraph 1 a and b, Article 37A, and Article 38B of Law No. 20/2001 on the Amendment of Law No. 31/1999, is used only as supporting evidence when the principal case is proved. Meanwhile, how to maximize the implementation of the burden of proof on the perpetrators of corruption criminal act in which the public prosecutor brings a corruption case to Court, depends upon the nature of the case and the type of indictment. The system of burden of proof can be used to eradicate corruption in the Court if some policies and general principles of justice such as independency, impartiality, and legal certainty, are applied.

Keywords: burden of proof, perpetrator, corruption criminal act

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1744 Living Heritage(s) And Decoloniality: A Situational Analysis of the Great Zimbabwe World Heritage Site

Authors: Revai Boterere

Abstract:

The study explores the decolonial theory in the context of engaging with living heritages in the formally colonised through the case of the Great Zimbabwe World Heritage Site. It followed a qualitative research paradigm in the form of a situational analysis, with both primary and secondary data sources examined to enable an analysis focusing on the decolonial discourse and practice at Great Zimbabwe. Unlike the dominant model (in terms of interpretation) used at Great Zimbabwe, that of Thomas Huffman, which views the site as ruins, new literature (Ashton Sinamai, 2017, 2020; Webber Ndoro, 1994, 2005; ShadreckChirikure 2008, etal 2016; Njabulo Chipanguraetal 2019) on zimbabwe culture, Great Zimbabwe World Heritage Site is a living site, a shrine, and a cultural landscape. it argue that the new literature, perhaps decolonial, remain in the hands of academics and not synthesised down to the interpreters. This is a problem, and it needs to be addressed. There is need of a pragmatic thrust to decolonisation at the Great Zimbabwe World Heritage Site. Though there are efforts to involve local communities at Great Zimbabwe as a decolonial approach, there is need to reorder the current system of producing knowledge in place. This paper will unpack these debates of decoloniality between what Huffman’s propositions of the interpretation of Great Zimbabwe vis-a-vis the new decolonial school of thought by local researchers.

Keywords: cultural tourism, decoloniality, living heritage, local community

Procedia PDF Downloads 104
1743 Design, Implementation and Evaluation of Health and Social Justice Trainings in Nigeria

Authors: Juliet Sorensen, Anna Maitland

Abstract:

Introduction: Characterized by lack of water and sanitation, food insecurity, and low access to hospitals and clinics, informal urban settlements in Lagos, Nigeria have very poor health outcomes. With little education and a general inability to demand basic rights, these communities are often disempowered and isolated from understanding, claiming, or owning their health needs. Utilizing community-based participatory research characterized by interdisciplinary, cross-cultural partnerships, evidence-based assessments, and both primary and secondary source research, a holistic health education and advocacy program was developed in Lagos to address health barriers for targeted communities. This includes a first of its kind guide formulated to teach community-based health educators how to transmit health information to low-literacy Nigerian audiences while supporting behavior change models and social support mechanisms. This paper discusses the interdisciplinary contributions to developing a health education program while also looking at the need for greater beneficiary ownership and implementation of health justice and access. Methods: In March 2016, an interdisciplinary group of medical, legal, and business graduate students and faculty from Northwestern University conduced a Health Needs Assessment (HNA) in Lagos with a partner and a local non-governmental organization. The HNA revealed that members of informal urban communities in Lagos were lacking basic health literacy, but desired to remedy this lacuna. Further, the HNA revealed that even where the government mandates specific services, many vulnerable populations are unable to access these services. The HNA concluded that a program focused on education, advocacy, and organizing around anatomy, maternal and sexual health, infectious disease and malaria, HIV/AIDS, emergency care, and water and sanitation would respond to stated needs while also building capacity in communities to address health barriers. Results: Based on the HNA, including both primary and secondary source research on integrated health education approaches and behavior change models and responsive, adaptive material development, a holistic program was developed for the Lagos partners and first implemented in November 2016. This program trained community-nominated health educators in adult, low-literacy, knowledge exchange approaches, utilizing information identified by communities as a priority. After a second training in March 2017, these educators will teach community-based groups and will support and facilitate behavior change models and peer-support methods around basic issues like hand washing and disease transmission. They will be supported by community paralegals who will help ensure that newly trained community groups can act on education around access, such as receiving free vaccinations, maternal health care, and HIV/AIDS medicines. Materials will continue to be updated as needs and issues arise, with a focus on identifying best practices around health improvements that can be shared across these partner communities. Conclusion: These materials are the first of their kind, and address a void of health information and understanding pervasive in informal-urban Lagos communities. Initial feedback indicates high levels of commitment and interest, as well as investment by communities in these materials, largely because they are responsive, targeted, and build community capacity. This methodology is an important step in dignity-based health justice solutions, albeit in the process of refinement.

Keywords: community health educators, interdisciplinary and cross cultural partnerships, health justice and access, Nigeria

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1742 Experimental Investigation of Partially Premixed Laminar Methane/Air Co-Flow Flames Using Mach-Zehnder Interferometry

Authors: Misagh Irandoost Shahrestani, Mehdi Ashjaee, Shahrokh Zandieh Vakili

Abstract:

In this paper, partially premixed laminar methane/air co-flow flame is studied experimentally. Methane-air flame was established on an axisymmetric coannular burner. The fuel-air jet flows from the central tube while the secondary air flows from the region between the inner and the outer tube. The aim is to investigate the flame features and to develop a nonintrusive method for temperature measurement of methane/air partially premixed flame using Mach-Zehnder interferometry method. Different equivalence ratios and Reynolds numbers are considered. Flame generic visible appearance was also investigated and its various structures were studied. Three distinguished flame regimes were seen based on its appearance. A double flame structure can be seen for the equivalence ratio in the range of 1<Φ<2.1. By adding air to the mixture up to Φ=4 the flame has the characteristics of both premixed and non-premixed flames. Finally for 4<Φ<∞ the flame mainly becomes non-premixed like and the luminous sooting region on its tip is the obvious feature of this type of flames. The Mach-Zehnder method is used to obtain temperature field of a transparent fluid by means of index of refraction. Temperature obtained from optical techniques was compared with that of obtained from thermocouples in order to validate the results. Good agreement was observed for these two methods.

Keywords: flame structure, Mach-Zehnder interferometry, partially premixed flame, temperature field

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1741 Influence of Cation Substitution on Magnetic Transitions and Ordering in La2NixCo1-xMnO6 Compounds (x = 0.2 - 0.8)

Authors: Amine.Harbia, Hicham. Moutaabbidb, Yann. Le Godecb, Said. Benmokhtara, Mouhammed. Moutaabbida

Abstract:

This study explores the structural and magnetic characteristics of newly synthesized double perovskite oxides, La₂NiₓCo1-xMnO₆, with x ranging from 0.2 to 0.8. Utilizing X-ray powder diffraction and SQUID magnetometry, we analyzed the compounds that consistently exhibit a monoclinic structure with the P21/n space group at ambient temperature. it findings reveal that as Ni2+ is progressively substituted by Co2+, there is a corresponding decrease in cell parameters, attributable to the smaller ionic radius of Ni2+ (0.69 Å) compared to Co2+ (0.74 Å). The crystal structure features octahedrally coordinated (Co/Ni)2+ and Mn4+ cations with oxygen, forming (Co/Ni)O6 and MnO6 octahedra linked via oxygen atoms along different crystallographic axes. Magnetic characterization conducted over a temperature range of 2 to 300 K in both DC and AC magnetic fields, showed a predominant paramagnetic to ferromagnetic transition between 232 K and 260 K, with the Curie temperature notably increasing with higher x values. Samples with x=0.2, 0.25, and 0.5 exhibited a secondary PM-FM transition between 200 K and 208 K. Cation ordering was quantitatively assessed, indicating a higher ordering in Ni2+-rich samples (x=0.75 and 0.8) at over 96%, whereas the sample with x=0.25 showed minimal ordering. Furthermore, the out-of-phase component of the AC susceptibility displayed frequency-dependent transitions between 65 K and 110 K, suggesting the presence of superparamagnetic domains across all samples.

Keywords: double perovskite oxides, magnetic transitions, cation ordering, squid magnetometry

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1740 Cyclic Plastic Deformation of 20MN-MO-NI 55 Steel in Dynamic Strain Ageing Regime

Authors: Ashok Kumar, Sarita Sahu, H. N. Bar

Abstract:

Low cycle fatigue behavior of a ferritic, martensitic pressure vessel steel at dynamic strain ageing regime of 250°C to 280°C has been investigated. Dynamic strain ageing is a mechanism that has attracted interests of researchers due to its fascinating inexplicable repetitive nature for quite a long time. The interaction of dynamic strain ageing and cyclic plasticity has been studied from the mechanistic point of view. Dynamic strain ageing gives rise to identical serrated flow behavior in tensile and compressive halves of hysteresis loops and this has been found to gives rise to initial cyclic hardening followed by softening behavior, where as in non-DSA regime continuous cyclic softening has been found to be the dominant mechanism. An appreciable sensitivity towards nature of serrations has been observed due to degree of hardening of stable loop. The increase in degree of hardening with strain amplitude in the regime where only A type serrations are present and it decreases with strain amplitude where A+B type of serrations are present. Masing type of locus has been found in the behavior of metal at 280°C. Cyclic Stress Strain curve and Master curve has been constructed to decipher among the fatigue strength and ductility coefficients. Fractographic examinations have also shown a competition between progression of striations and secondary cracking.

Keywords: dynamic strain ageing, hardening, low cycle fatigue, softening

Procedia PDF Downloads 299