Search results for: crack growth
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6630

Search results for: crack growth

5040 Adolescents’ and Young Adults’ Well-Being, Health, and Loneliness during the COVID-19 Pandemic

Authors: Jessica Hemberg, Amanda Sundqvist, Yulia Korzhina, Lillemor Östman, Sofia Gylfe, Frida Gädda, Lisbet Nyström, Henrik Groundstroem, Pia Nyman-Kurkiala

Abstract:

Purpose: There are large gaps in the literature on COVID-19 pandemic-related mental health outcomes and after-effects specific to adolescents and young adults. The study's aim was to explore adolescents’ and young adults’ experiences of well-being, health, and loneliness during the COVID-19 pandemic. Method: A qualitative exploratory design with qualitative content analysis was used. Twenty-three participants (aged 19-27; four men and 19 women) were interviewed. Results: Four themes emerged: Changed social networks – fewer and closer contacts, changed mental and physical health, increased physical and social loneliness, well-being, internal growth, and need for support. Conclusion: Adolescents’ and young adults’ experiences of well-being, health, and loneliness are subtle and complex. Participants experienced changed social networks, mental and physical health, and well-being. Also, internal growth, need for support, and increased loneliness were seen. Clear information on how to seek help and support from professionals should be made available.

Keywords: adolescents, COVID-19 pandemic, health, interviews, loneliness, qualitative, well-being, young adults

Procedia PDF Downloads 79
5039 Ge₁₋ₓSnₓ Alloys with Tuneable Energy Band Gap on GaAs (100) Substrate Manufactured by a Modified Magnetron Co-Sputtering

Authors: Li Qian, Jinchao Tong, Daohua Zhang, Weijun Fan, Fei Suo

Abstract:

Photonic applications based on group IV semiconductors have always been an interest but also a challenge for the research community. We report manufacturing group IV Ge₁₋ₓSnₓ alloys with tuneable energy band gap on (100) GaAs substrate by a modified radio frequency magnetron co-sputtering. Images were taken by atomic force microscope, and scanning electron microscope clearly demonstrates a smooth surface profile, and Ge₁₋ₓSnₓ nano clusters are with the size of several tens of nanometers. Transmittance spectra were measured by Fourier Transform Infrared Spectroscopy that showed changing energy gaps with the variation in elementary composition. Calculation results by 8-band k.p method are consistent with measured gaps. Our deposition system realized direct growth of Ge₁₋ₓSnₓ thin film on GaAs (100) substrate by sputtering. This simple deposition method was modified to be able to grow high-quality photonic materials with tuneable energy gaps. This work provides an alternative and successful method for fabricating Group IV photonic semiconductor materials.

Keywords: GeSn, crystal growth, sputtering, photonic

Procedia PDF Downloads 133
5038 Anti-Bubble Painting Booth for Wood Coating Resins

Authors: Abasali Masoumi, Amir Gholamian Bozorgi

Abstract:

To have the best quality in wood products such as tabletops and inlay-woods, applying two principles are required: aesthetic and protection against the destructive agent. Artists spent a lot of time creating a masterwork project and also for better demonstrating beautiful appearance and preserving it for hundred years. So they need good material and appropriate method to finish it. As usual, wood painters use polyester or epoxy resins. These finishes need a special skill to use and then give a fantastic paint film and clearness. If we let resins dry in exposure to environmental agents such as unstable temperature, dust and etc., no doubt it becomes cloudy, crack, blister and much wood dust and air bubbles in it. We have designed a special wood coating booth (IR-Patent No: 70429) for wood-coating resins (polyester and epoxy), and this booth provides an adjustable space to control factors that is necessary to have a good finish in the end. Anti-bubble painting booth has the ability to remove bubbles from resin, precludes the cracking process and causes the resin to be the best. With this booth drying time of resin is reduced from 24 hours to 6 hours by fixing the optimum temperature, and it is very good for saving time. This booth is environment-friendly and never lets the poisonous vapors and other VOC (Volatile organic components) enter to workplace atmosphere because they are very harmful to humans.

Keywords: wood coating, epoxy resin, polyester resin, wood finishes

Procedia PDF Downloads 207
5037 Colorful Textiles with Antimicrobial Property Using Natural Dyes as Effective Green Finishing Agents

Authors: Shahid-ul-Islam, Faqeer Mohammad

Abstract:

The present study was conducted to investigate the effect of annatto, teak and flame of the forest natural dyes on color, fastness, and antimicrobial property of protein based textile substrate. The color strength (K/S) of wool samples at various concentrations of dyes were analysed using a Reflective Spectrophotometer. The antimicrobial activity of natural dyes before and after application on wool was tested against common human pathogens Escherichia coli, Staphylococcus aureus, and Candida albicans, by using micro-broth dilution method, disc diffusion assay and growth curve studies. The structural morphology of natural protein fibre (wool) was investigated by Scanning Electron Microscopy (SEM). Annatto and teak natural dyes proved very effective in inhibiting the microbial growth in solution phase and after application on wool and resulted in a broad beautiful spectrum of colors with exceptional fastness properties. The results encourage the search and exploitation of new plant species as source of dyes to replace toxic synthetic antimicrobial agents currently used in textile industry.

Keywords: annatto, antimicrobial agents, natural dyes, green textiles

Procedia PDF Downloads 305
5036 Nutritional Indices and Biology of the Armyworm, Spodoptera litura on Five Cotton Varieties

Authors: Md. Ruhul Amin

Abstract:

The effects of CB1, CB3, CB5, CB8 and CB12 cotton varieties on the nutritional indices and biological parameters of armyworm Spodoptera litura were studied under laboratory conditions. The armyworm larvae showed the highest and lowest food consumption rates on CB8 and CB1 variety, respectively. The efficiency of the conversion of digested food, efficiency of conversion of ingested food, approximate digestibility rates were statistically higher and similar on CB5 and CB8, and lowest on CB1. The larvae reared on CB12 variety exerted the lowest feeding and growth indices, and the relative growth rate was highest on CB8. The survival rates of egg, larva, pupa and adult moths were found highest on CB8 and lowest on CB12. The development durations of the immature stages of the insect differed significantly and the time elapsed from egg-to-adult emergence, longevity of both male and female moths, and their lifecycle were shortest on CB12 variety. The nutritional indices and biological parameters of the armyworm indicated that the varieties CB5 and CB8 were suitable host plants for feeding and development of S. litura.

Keywords: gossypium hirsutum, spodoptera litura, food consumption, life history

Procedia PDF Downloads 361
5035 Impact of Coccidia on Mortality and Weight Growth in Japanese Quail Coturnix japonica (Aves, Phasianidae) in Algeria

Authors: Amina Smai, Fairouz Haddadj, Habiba Saadi-Idouhar, Meriem Aissi, Safia Zenia, Salaheddine Doumandji

Abstract:

Coccidiosis is a very common intestinal parasitic disease caused by a worldwide distributed protozoan of the genus Eimeria. This disease is very common in young birds beyond the second week of life, especially in land-based breeding. The study was carried out in a hunting center of Zeralda located in the north-east of Algiers. The objective of our work is to study the evolution of coccidiosis in quails from 1 to 35 days old by collecting their droppings daily. These are analyzed in the laboratory using the flotation method and the Mac Master one to count coccidia. Weight changes are taken into account as well as mortality in parallel with certain zootechnical parameters such as density. The species of coccidia recovered is Eimeria coturnicis. The results showed that there is an average evolution of mortality of individuals with a rate of 13.33% due to the presence of coccidia with a significant regression (p=0.031). The weight of the quails increases with the age of the animal with a rapid growth rate from the 3rd week onwards. Indeed, the statistical analysis reveals that the evolution of the number did not affect the evolution of the weight (p=0.70) and the GMQ (R=0.52).

Keywords: coccidiosis, Coturnix japonica, daily average gain, weight

Procedia PDF Downloads 165
5034 Study of Electro-Chemical Properties of ZnO Nanowires for Various Application

Authors: Meera A. Albloushi, Adel B. Gougam

Abstract:

The development in the field of piezoelectrics has led to a renewed interest in ZnO nanowires (NWs) as a promising material in the nanogenerator devices category. It can be used as a power source for self-powered electronic systems with higher density, higher efficiency, longer lifetime, as well as lower cost of fabrication. Highly aligned ZnO nanowires seem to exhibit a higher performance compared with nonaligned ones. The purpose of this study was to develop ZnO nanowires and to investigate their electrical and chemical properties for various applications. They were grown on silicon (100) and glass substrates. We have used a low temperature and non-hazardous method: aqueous chemical growth (ACG). ZnO (non-doped) and AZO (Aluminum doped) seed layers were deposited using RF magnetron sputteringunder Argon pressure of 3 mTorr and deposition power of 180 W, the times of growth were selected to obtain thicknesses in the range of 30 to 125 nm. Some of the films were subsequently annealed. The substrates were immersed tilted in an equimolar solution composed of zinc nitrate and hexamine (HMTA) of 0.02 M and 0.05 M in the temperature range of 80 to 90 ᵒC for 1.5 to 2 hours. The X-ray diffractometer shows strong peaks at 2Ө = 34.2ᵒ of ZnO films which indicates that the films have a preferred c-axis wurtzite hexagonal (002) orientation. The surface morphology of the films is investigated by atomic force microscope (AFM) which proved the uniformity of the film since the roughness is within 5 nm range. The scanning electron microscopes(SEM) (Quanta FEG 250, Quanta 3D FEG, Nova NanoSEM 650) are used to characterize both ZnO film and NWs. SEM images show forest of ZnO NWs grown vertically and have a range of length up to 2000 nm and diameter of 20-300 nm. The SEM images prove that the role of the seed layer is to enhance the vertical alignment of ZnO NWs at the pH solution of 5-6. Also electrical and optical properties of the NWs are carried out using Electrical Force Microscopy (EFM). After growing the ZnO NWs, developing the nano-generator is the second step of this study in order to determine the energy conversion efficiency and the power output.

Keywords: ZnO nanowires(NWs), aqueous chemical growth (ACG), piezoelectric NWs, harvesting enery

Procedia PDF Downloads 309
5033 Prenatal Exposure to Organophosphate Pesticide and Fetal Growth

Authors: Yi-Shuan ShaoShao, Yen-An Tsai, Chia-Huang Chang, Kai-Wei Liao, Ming-Song Tsai, Mei-Lien Chen

Abstract:

Organophosphate pesticides (OPs) is an environmental hormone with proven endocrine-disrupting effects that may affect the growth and development in human. A large amount of organophosphate pesticides (OPs) is used throughout Taiwan, and human may be exposed through dietary intake or residential use. During pregnancy, OPs can be transferred to the blood stream reaching the fetus through the placenta. The aim of this study was to explore the association between maternal OPs exposure levels and fetal developments and birth outcomes. A birth cohort was follow-up. Maternal urine sample were collected at the first, second, and third gestational trimester. Fetal growth characteristics were measured by ultrasonic scan and birth outcomes were assessed by pediatrician. Urinary metabolite of organophosphate pesticides were assessed using gas chromatography-mass spectrometry. The analytes included dimethylphosphate (DMP), dimethylthiophosphate (DMTP), dimethyldithiophosphates (DMDTP), diethylphosphate (DEP), diethylthiophosphate (DETP), and diethyldithiophosphate (DEDTP). We found that all of urine samples in each trimester were detected at least one metabolite for dialkyl phosphate (DAP). The detection rate range of OP urinary metabolites were from the lowest 22% DEDTP to the highest 100% DMP and DMTP. And to compared geometric means (GM) of urinary metabolites with three trimesters, that third trimester had the highest concentration for DMPs, DEPs, and DAPs in pregnant women were 368.01, 169.85 and 543.75 nmol/g creatinine, respectively. We observed that DAPs concentration in first and second trimester were significantly negative association with head circumference. DMPs in first trimester was significantly negative association with thoracic circumference (p=0.05) by spearman correlation. Our results support associations with prenatal OPs exposure with fetal head circumference and thoracic circumference. It provided that maternal OPs exposure might affect birth outcomes. Thus, prenatal exposure to OPs and health risk worthy of attention and concern.

Keywords: DAPs, birth outcomes, organophosphate pesticides, prenatal

Procedia PDF Downloads 328
5032 Bridging Stress Modeling of Composite Materials Reinforced by Fiber Using Discrete Element Method

Authors: Chong Wang, Kellem M. Soares, Luis E. Kosteski

Abstract:

The problem of toughening in brittle materials reinforced by fibers is complex, involving all the mechanical properties of fibers, matrix, the fiber/matrix interface, as well as the geometry of the fiber. An appropriate method applicable to the simulation and analysis of toughening is essential. In this work, we performed simulations and analysis of toughening in brittle matrix reinforced by randomly distributed fibers by means of the discrete elements method. At first, we put forward a mechanical model of the contribution of random fibers to the toughening of composite. Then with numerical programming, we investigated the stress, damage and bridging force in the composite material when a crack appeared in the brittle matrix. From the results obtained, we conclude that: (i) fibers with high strength and low elasticity modulus benefit toughening; (ii) fibers with relatively high elastic modulus compared to the matrix may result in considerable matrix damage (spalling effect); (iii) employment of high-strength synthetic fiber is a good option. The present work makes it possible to optimize the parameters in order to produce advanced ceramic with desired performance. We believe combination of the discrete element method (DEM) with the finite element method (FEM) can increase the versatility and efficiency of the software developed.

Keywords: bridging stress, discrete element method, fiber reinforced composites, toughening

Procedia PDF Downloads 429
5031 Developing a Shadow Port: A Case Study of Bangkok Port and Laem Chabang Port, Thailand

Authors: C. Bamrungbutr, J. Sillitoe

Abstract:

Maritime transportation has been a crucial part of world economics. Recently, researchers have put effort into studying the mechanisms of how a regional port, in the shadow of a nearby predominant port, can compete and grow. However, limited research has focused on the competition issues for a shadow port which is a capital city port. This study will thus focus on this question of the growth of a capital city port which is under the shadow of the adjacent capital city port by using the two capital city ports of Thailand; Bangkok port (the former main port) and Laem Chabang port (the current main port). For this work, a framework of opportunity capture will be used, and five groups of port development experts (government, council, logistics provider, academia and industry) will be interviewed. The responses will be analysed using the noticing, collecting and thinking model. The resulting analysis will be appropriate for use in developing guidelines for the future management of a range of shadow ports established in a capital city, enabling them to operate in a competitive environment more effectively. The resultant growth of these ports will be a significant factor in increasing the competitiveness of a nation’s maritime transport industry and eventually lead to a boost in the national economy.

Keywords: shadow port, Bangkok Port, Laem Chabang Port, port competition

Procedia PDF Downloads 158
5030 High Temperature Properties of Diffusion Brazed Joints of in 939 Ni-Base Superalloy

Authors: Hyun KI Kang, Hi Won Jeong

Abstract:

The gas turbine operates for a long period of time under harsh, cyclic conditions of high temperature and pressure, where high turbine inlet temperature (TIT) can range from 1273 to 1873K. Therefore, Ni-base superalloys such as IN738, IN939, Rene 45, Rene 71, Rene 80, Mar M 247, CM 247, and CMSX-4 with excellent mechanical properties and resistance to creep, corrosion and oxidation at high temperatures are indeed used. Among the alloying additions for these alloys, aluminum (Al) and titanium (Ti) form gamma prime and enhance the high-temperature properties. However, when crack-damaged high-temperature turbine components such as blade and vane are repaired by fusion welding, they cause cracks. For example, when arc welding is applied to certain superalloys that contain Al and Ti with more than 3 wt.% and T3.5 wt%, respectively, such as IN738, IN939, Rene 80, Mar M 247, and CM 247, aging cracks occur. Therefore, repair technologies using diffusion brazing, which has less heat input into the base material, are being developed. Analysis of microstructural evolution of the brazed joints with a base metal of IN 939 Ni-base superalloy using brazing different filler metals was also carried out using X-ray diffraction, OEM, SEM-EDS, and EPMA. Stress rupture and high-temperature tensile strength properties were also measured to analyze the effects of different brazing heat cycles. The boron amount in the diffusion-affected zone (DAZ) was decreased towards the base metal and the formation of borides at grain boundaries was detected through EPMA.

Keywords: gas turbine, diffusion brazing, superalloy, gas turbine repair

Procedia PDF Downloads 28
5029 Mainland China and Taiwan’s Strategies for Overcoming the Middle/High Income Trap: Domestic Consensus-Building and the Foundations of Cross-Strait Interactions

Authors: Mingke Ma

Abstract:

The recent discovery of the High-Income Trap phenomena and the established Middle-Income Trap literature have identified the similarity of the structural challenges that both Mainland China and Taiwan have been facing since the simultaneous growth slowdown from the 2000s. Mainland China and Taiwan’s ineffectiveness in productivity growth weakened their overall competitiveness in Global Value Chains. With the subsequent decline of industrial profitability, social compression from late development persists and jeopardises the social cohesion. From Ma Ying-jeou’s ‘633’ promise and Tsai Ing-wen’s ‘5+2’ industrial framework to Mainland China’s 11th to 14th Five-Year Plans, leaderships across the Strait have been striving to constitute new models for inclusive and sustainable development through policy responses. This study argues that social consensuses that have been constructed by the domestic political processes define the feasibility of the reform strategies, which further construct the conditions for Cross-Strait interactions. Based on the existing literature of New Institutional Economics, Middle/High Income Trap, and Compressed Development, this study adopts a Historical Institutionalist analytical framework to identify how the historical path-dependency contributes to the contemporary growth constraints in both economies and the political difficulty on navigating the institutional and Organisational change. It continues by tracing the political process of economic reform to examine the sustainability and resilience of the manifested social consensus that had empowered the proposed policy frameworks. Afterwards, it examines how the political outcomes in such a simultaneous process shared by both Mainland China and Taiwan construct the social, economic, institutional, and political foundations of contemporary Cross-Strait engagement.

Keywords: historical institutionalism, political economy, cross-strait relations, high/middle income trap

Procedia PDF Downloads 176
5028 Effect of Segregation Pattern of Mn, Si, and C on through Thickness Microstructure and Properties of Hot Rolled Steel

Authors: Waleed M. Al-Othman, Hamid Bayati, Abdullah Al-Shahrani, Haitham Al-Jabr

Abstract:

Pearlite bands commonly form parallel to the surface of the hot rolled steel and have significant influence on the properties of the steel. This study investigated the correlation between segregation pattern of Mn, Si, C and formation of the pearlite bands in hot rolled Gr 60 steel plate. Microstructural study indicated formation of a distinguished thick band at centerline of the plate with number of parallel bands through thickness of the steel plate. The thickness, frequency, and continuity of the bands are reduced from mid-thickness toward external surface of the steel plate. Analysis showed a noticeable increase of C, Si and Mn levels within the bands. Such alloying segregation takes place during metal solidification. EDS analysis verified presence of particles rich in Ti, Nb, Mn, C, N, within the bands. Texture analysis by Electron Backscatter Detector (EBSD) indicated the grains size/misorientation can noticeably change within the bands. Effect of banding on through-thickness properties of the steel was examined by carrying out microhardness, toughness and tensile tests. Results suggest the Mn and C contents are changed in sinusoidal pattern through thickness of the hot rolled plate and pearlite bands are formed at the peaks of this sinusoidal segregation pattern. Changes in grain size/misorientation, formation of highly alloyed particles, and pearlite within these bands, facilitate crack formation along boundaries of these bands.

Keywords: pearlite band, alloying segregation, hot rolling, Ti, Nb, N, C

Procedia PDF Downloads 121
5027 Entrepreneurship Cure for Economic Under-Development in Nigeria: A Theoretical Perspective

Authors: Kurotimi Maurice Fems, Abara Onu, Francis W. D. Poazi

Abstract:

Scholars and development economists believe that the development of an economy depends largely on the creative and innovative ingenuity of its entrepreneurs. Others however, are of the opinion that the lack of entrepreneurs or entrepreneurial activities is not a constraint to economic development in any economy, particularly Nigeria. This paper sets out to explore the connectivity between entrepreneurship and economic development from a theoretical point of view, principally in Nigeria. A desk research approach was adopted where a conglomerate of literatures was reviewed on how entrepreneurship can spur economic growth or otherwise. The findings reveal that entrepreneurship is vital to the development of Nigeria and that, universities and other Higher Education Institutions must play the vital role of educating the people on entrepreneurship skills and competences. However, the problems and difficulties entrepreneurs face in Nigeria and the same problems suffocating the growth and development of its economy. Therefore, entrepreneurship cannot be said to be the sole cure for economic under-development in Nigeria but rather other factors such as empowering and granting the institutions autonomy and the provision of infrastructural capability, such as consistent electricity generation and supply, good system of transportation, implementing proposed economic policies in an effective and efficient manner etc., the cultural beliefs and mindset of the citizenry, was also found to be key in the development of any economy.

Keywords: economic underdevelopment, entrepreneurial, entrepreneurship, infrastructural under-development, oil boom, SMEs, unemployable

Procedia PDF Downloads 259
5026 Assessment of the Biological Nitrogen Fixation in Soybean Sown in Different Types of Moroccan Soils

Authors: F. Z. Aliyat, B. Ben Messaoud, L. Nassiri, E. Bouiamrine, J. Ibijbijen

Abstract:

The present study aims to assess the biological nitrogen fixation in the soybean tested in different Moroccan soils combined with the rhizobial inoculation. These effects were evaluated by the plant growth mainly by the aerial biomass production, total nitrogen content and the proportion of the nitrogen fixed. This assessment clearly shows that the inoculation with bacteria increases the growth of soybean. Five different soils and a control (peat) were used. The rhizobial inoculation was performed by applying the peat that contained a mixture of 2 strains Sinorhizobium fredii HH103 and Bradyrhizobium. The biomass, the total nitrogen content and the proportion of nitrogen fixed were evaluated under different treatments. The essay was realized at the greenhouse the Faculty of Sciences, Moulay Ismail University. The soybean has shown a great response for the parameters assessed. Moreover, the best response was reported by the inoculated plants compared to non- inoculated and to the absolute control. Finally, good production and the best biological nitrogen fixation present an important ecological technology to improve the sustainable production of soybean and to ensure the increase of the fertility of soils.

Keywords: biological nitrogen fixation, inoculation, rhizobium, soybean

Procedia PDF Downloads 156
5025 Spectrophotometric Evaluation of Custom Microalgae-Based Bioink Formulations for Optimized Green Bioprinting

Authors: Olubusuyi Ayowole, Bashir Khoda

Abstract:

Green bioprinting, from the context of merging 3D bioprinting with microalgae cell organization, holds promise for industrial-scale optimization. This study employs spectrophotometric analysis to explore post-bioprinting cell growth density variation within hybrid hydrogel biomaterial scaffolds. Three hydrogel biomaterials—Alginic acid sodium salt (ALGINATE), Nanofibrillated Cellulose (NFC) – TEMPO, and CarboxyMethyl Cellulose (CMC)—are chosen for their scaffolding capabilities. Bioink development and analysis of their impact on cell proliferation and morphology are conducted. Chlorella microalgae cell growth within hydrogel compositions is probed using absorbance measurements, with additional assessment of shear thinning properties. Notably, NFC exhibits reduced shear thinning compared to CMC. Results reveal that while mono-hydrogel substrates with pronounced adhesion inhibit Chlorella cell proliferation, Alginate fosters increased cell concentration alongside a slight viscosity rise.

Keywords: green bioprinting, 3d bioprinting, microalgae cell, hybrid hydrogel scaffolds, spectrophotometric analysis, bioink development, shear thinning properties

Procedia PDF Downloads 4
5024 Phenomenological Analysis on the Experience of Volunteer Activities in Pre-Medical School Students

Authors: S. J. Yune, K. H. Park

Abstract:

The purpose of this study was to understand the experiences of medical students in volunteer activities and to draw implications for medical education. For this purpose, the questionnaire and the reflection essay on the volunteer experience of 54 students in the first year and 57 students in the second year were analyzed and analyzed. As a result, the participation of the students in the volunteer activities was the highest in the first semester and once a month in the second grade. Activities were mostly through volunteer organizations. The essence of the volunteering activities experience revealed through reflection essays was 'I want to avoid with fear' and 'I feel far away' in the recognition before volunteering activities. In terms of knowledge after participating in volunteer activities, 'breaking eggs and getting to know the world' and 'intellectual growth through social experience' appeared. In terms of attitude, it revealed 'deep reflection on me and others', 'understanding of service life'. And in terms of behavior, 'Begin preparing for a life of service' appeared. The results of this study revealed that volunteering activities provide students with opportunities for growth and development. In order to obtain more meaningful results, consciousness education related to social service should be done in advance.

Keywords: volunteering activity, pre-medical school student, reflection essay, qualitative analysis

Procedia PDF Downloads 171
5023 Impact of innovative Solar Heating Systems on Greenhouse ‎Microclimates: A Case Study with Zucchini (Cucurbita pepo)‎

Authors: Ilham Ihoume, Rachid Tadili, Nora Arbaoui

Abstract:

Recent innovations in economical heating systems have significantly boosted ‎agricultural production by effectively managing temperature drops in greenhouse ‎microclimates. These advancements enhance product profitability in terms of quality, ‎quantity, and growth duration. This study experimentally investigates the impact of a ‎solar heating system on the microclimate of an agricultural greenhouse, focusing on ‎zucchini (Cucurbita pepo). The System comprises a copper tube placed between double ‎roof glazing and a sensible heat storage system, converting solar energy during the day ‎and storing it for night-time release. A second control greenhouse without heating ‎allows for comparative analysis at various growth stages. During the cold season, the ‎experimental greenhouse showed a temperature increase of 3°C compared to the ‎control greenhouse and 5°C above external ambient air. The relative humidity in the ‎experimental greenhouse ranged from 69% to 70%, whereas the control greenhouse recorded 68% to 86%, and ambient air ‎was between 94% to 99%. The heating systems achieved an efficiency of 73%, and ‎zucchini plants in the experimental greenhouse developed fruit 13 days earlier than ‎those in the control greenhouse.‎

Keywords: solar energy, storage, energy managment, heating system

Procedia PDF Downloads 20
5022 Evaluation of Growth Performance and Survival Rate of African Catfish (Clarias gariepinus) Fed with Graded Levels of Egg Shell Substituted Ration

Authors: A. Bello-Olusoji, M. O. Sodamola, Y. A. Adejola, D. D Akinbola

Abstract:

An eight (8) weeks study was carried out on Four hundred and five (405) African catfish (Clarias gariepinus) juveniles to examine the effect of graded levels of egg shell on their growth performance and survival rates. They were acclimatized for two (2) weeks after which they were weighed and allotted into five dietary treatments of three (3) replicates each and 27 fishes per replicate making a total number of eighty-one (81) fishes per treatment. The dietary treatments contained 0, 25, 50, 75 and 100(%) egg shell inclusion from treatment one to treatment five respectively. Parameter on daily feed intake, weekly weight gain, and daily mortalities were recorded. The result of the experiment indicated that treatment four (4) with 75% inclusion of egg shell was the best in terms of weight gain and survival rates and was significantly different (P<0.05) when compared with the other treatments. For Catfish farming to remain viable in the nearest future, lower feed cost and increased profit are required; it is therefore recommended that diets of African catfish (Clarias gariepinus) be supplemented with well processed egg shell at 75% level of inclusion to achieve this.

Keywords: African catfish, egg shell, performance, performance, survival rate, weight gain

Procedia PDF Downloads 369
5021 Application of Crude Palm Oil Liquid Sludge Sewage On Maize (Zea mays. L) as Re-Cycle Possibility to Fertilizer

Authors: Hasan Basri Jumin, Henni Rosneti, Agusnimar

Abstract:

Crude palm oil liquid sludge sewage was treated to maize with 400 cc/plant could be increased mean relative growth rates, net assimilation rate, leaf area and dry weight of seed. There are indicated that 400 cc / plant treated to maize significantly increase the average of mean relative growth rates into 0.32 g.day-1. Net assimilation rates increase from 13.5 mg.m-2.day-1 into 34.5 mg.m-2.day-1, leaf area at 50 days after planting increase from 1419 cm-2 into 2458 cm-2 and dry weight of seed from 38 g per plant into 43 g per plant. Crude palm oil liquid sludge waste chemical analysis indicated that, there are no exceed threshold content of dangerous metals and biology effects. Cadmium content as heavy metal is lower than threshold of human healthy tolerance. Therefore, it has no syndrome effect to human health. Biological oxygen demands and chemical oxygen demands as indicators for micro-organism activities, there are under the threshold of human healthy tolerance.

Keywords: crude-palm-oil, fertilizer, liquid-sludge, maize, pollutant, waste

Procedia PDF Downloads 553
5020 Antimicrobial Activity of Different Essential Oils in Synergy with Amoxicillin against Clinical Isolates of Methicillin-Resistant Staphylococcus aureus

Authors: Naheed Niaz, Nimra Naeem, Bushra Uzair, Riffat Tahira

Abstract:

Antibacterial activity of different traditional plants essential oils against clinical isolates of Methicillin-resistant Staphylococcus aureus (MRSA) through disk diffusion method was evaluated. All the tested essential oils, in different concentrations, inhibited growth of S. aureus to varying degrees. Cinnamon and Thyme essential oils were observed to be the “best” against test pathogen. Even at lowest concentration of these essential oils i.e. 25 µl/ml, clear zone of inhibition was recorded 9+0.085mm and 8+0.051mm respectively, and at higher concentrations there was a total reduction in growth of MRSA. The study also focused on analyzing the synergistic effects of essential oils in combination with amoxicillin. Results showed that oregano and pennyroyal mint essential oils which were not very effective alone turned out to be strong synergistic enhancers. The activity increased with increase in concentration of the essential oils. It may be concluded from present results that cinnamon and thyme essential oils could be used as potential antimicrobial source for the treatment of infections caused by Methicillin-resistant Staphylococcus aureus (MRSA).

Keywords: Staphylococcus aureus, essential oils, antibiotics, combination therapy, minimum inhibitory concentration

Procedia PDF Downloads 432
5019 Financial Sources and Instruments for Public Grants and Financial Facilities of SMEs in Eu

Authors: Simeon Karafolas, Maciej Woźniak

Abstract:

Mostly of public financing programs at national and regional level are funded from European Union sources. EU can participate directly to a national and regional program (example LEADER initiative, URBAN…) or indirectly by funding regional or national funds. Funds from European Union are provided from EU multiannual financial framework form which the annual budget is programmed. The adjusted program 2007-2013 of the EU considered commitments of almost 1 trillion Euros for the EU-28 countries. Provisions of the new program 2014-2020 consider commitments of more than 1 trillion Euros. Sustainable growth, divided to Cohesion and Competitiveness for Growth an Employment, is one of the two principal categories; the other is the preservation and management of natural resources. Through this financing process SMEs benefited of EU and public sources by receiving grants for their investments. Most of the financial instruments are available indirectly through the national financial intermediaries. Part of them is managed by the European Investment Fund. The paper focuses on the public financing to SMEs by examining case studies on divers forms of public help. It tries to distinguish the efficiency of the examined good practices and therefore try to have some conclusions on the possibility of application to other regions.

Keywords: DIFASS, grants, SMEs, public financing

Procedia PDF Downloads 289
5018 Evaluation of Beam Structure Using Non-Destructive Vibration-Based Damage Detection Method

Authors: Bashir Ahmad Aasim, Abdul Khaliq Karimi, Jun Tomiyama

Abstract:

Material aging is one of the vital issues among all the civil, mechanical, and aerospace engineering societies. Sustenance and reliability of concrete, which is the widely used material in the world, is the focal point in civil engineering societies. For few decades, researchers have been able to present some form algorithms that could lead to evaluate a structure globally rather than locally without harming its serviceability and traffic interference. The algorithms could help presenting different methods for evaluating structures non-destructively. In this paper, a non-destructive vibration-based damage detection method is adopted to evaluate two concrete beams, one being in a healthy state while the second one contains a crack on its bottom vicinity. The study discusses that damage in a structure affects modal parameters (natural frequency, mode shape, and damping ratio), which are the function of physical properties (mass, stiffness, and damping). The assessment is carried out to acquire the natural frequency of the sound beam. Next, the vibration response is recorded from the cracked beam. Eventually, both results are compared to know the variation in the natural frequencies of both beams. The study concludes that damage can be detected using vibration characteristics of a structural member considering the decline occurred in the natural frequency of the cracked beam.

Keywords: concrete beam, natural frequency, non-destructive testing, vibration characteristics

Procedia PDF Downloads 99
5017 The Effect of a Weed-Killer Sulfonylurea on Durum Wheat (Triticum Durum Desf)

Authors: L. Meksem Amara, M. Ferfar, N. Meksem, M. R. Djebar

Abstract:

The wheat is the cereal the most consumed in the world. In Algeria, the production of this cereal covers only 20 in 25 % of the needs for the country, the rest being imported. To improve the efficiency and the productivity of the durum wheat, the farmers turn to the use of pesticides: weed-killers, fungicides and insecticides. However this use often entrains losses of products more at least important contaminating the environment and all the food chain. Weed-killers are substances developed to control or destroy plants considered unwanted. That they are natural or produced by the human being (molecule of synthesis), the absorption and the metabolization of weed-killers by plants cause the death of these plants. In this work, we set as goal the evaluation of the effect of a weed-killer sulfonylurea, the CossackOD with various concentrations (0, 2, 4 and 9 µg) on variety of Triticum durum: Cirta. We evaluated the plant growth by measuring the leaves and root length, compared with the witness as well as the content of proline and analyze the level of one of the antioxydative enzymes: catalase, after 14 days of treatment. Sulfonylurea is foliar and root weed-killers inhibiting the acetolactate synthase: a vegetable enzyme essential to the development of the plant. This inhibition causes the ruling of the growth then the death. The obtained results show a diminution of the average length of leaves and roots this can be explained by the fact that the ALS inhibitors are more active in the young and increasing regions of the plant, what inhibits the cellular division and talks a limitation of the foliar and root’s growth. We also recorded a highly significant increase in the proline levels and a stimulation of the catalase activity. As a response to increasing the herbicide concentrations a particular increases in antioxidative mechanisms in wheat cultivar Cirta suggest that the high sensitivity of Cirta to this sulfonylurea herbicide is related to the enhanced production and oxidative damage of reactive oxygen species.

Keywords: sulfonylurea, triticum durum, oxydative stress, toxicity

Procedia PDF Downloads 393
5016 Nationalization of the Social Life in Argentina: Accumulation of Capital, State Intervention, Labor Market, and System of Rights in the Last Decades

Authors: Mauro Cristeche

Abstract:

This work begins with a very simple question: How does the State spend? Argentina is witnessing a process of growing nationalization of social life, so it is necessary to find out the explanations of the phenomenon on the specific dynamic of the capitalist mode of production in Argentina and its transformations in the last decades. Then the new question is: what happened in Argentina that could explain this phenomenon? Since the seventies, the capital growth in Argentina faces deep competitive problems. Until that moment the agrarian wealth had worked as a compensation mechanism, but it began to find its limits. In the meantime, some important demographical and structural changes had happened. The strategy of the capitalist class had to become to seek in the cheapness of the labor force the main source of compensation of its weakness. As a result, a tendency to worsen the living conditions and fragmentation of the working class started to develop, manifested by unemployment, underemployment, and the fall of the purchasing power of the salary as a highlighted fact. As a consequence, it is suggested that the role of the State became stronger and public expenditure increased, as a historical trend, because it has to intervene to face the contradictions and constant growth problems posed by the development of capitalism in Argentina. On the one hand, the State has to guarantee the process of buying the cheapened workforce and at the same time the process of reproduction of the working class. On the other hand, it has to help to reproduce the individual capitals but needs to ‘attack’ them in different ways. This is why the role of the State is said to be the general political representative to the national portion of the total social capital. What will be studied is the dynamic of the intervention of the Argentine State in the context of the particular national process of capital growth, and its dynamics in the last decades. What this paper wants to show are the main general causes that could explain the phenomenon of nationalization of the social life and how it has impacted the life conditions of the working class and the system of rights.

Keywords: Argentina, nationalization, public policies, rights, state

Procedia PDF Downloads 122
5015 Railway Crane Accident: A Comparative Metallographic Test on Pins Fractured during Operation

Authors: Thiago Viana

Abstract:

Eventually train accidents occur on railways and for some specific cases it is necessary to use a train rescue with a crane positioned under a platform wagon. These tumbled machines are collected and sent to the machine shop or scrap yard. In one of these cranes that were being used to rescue a wagon, occurred a fall of hoist due to fracture of two large pins. The two pins were collected and sent for failure analysis. This work investigates the main cause and the secondary causes for the initiation of the fatigue crack. All standard failure analysis procedures were applied, with careful evaluation of the characteristics of the material, fractured surfaces and, mainly, metallographic tests using an optical microscope to compare the geometry of the peaks and valleys of the thread of the pins and their respective seats. By metallographic analysis, it was concluded that the fatigue cracks were started from a notch (stress concentration) in the valley of the threads of the pin applied to the right side of the crane (pin 1). In this, it was verified that the peaks of the threads of the pin seat did not have proper geometry, with sharp edges being present that caused such notches. The visual analysis showed that fracture of the pin on the left side of the crane (pin 2) was brittle type, being a consequence of the fracture of the first one. Recommendations for this and other railway cranes have been made, such as nondestructive testing, stress calculation, design review, quality control and suitability of the mechanical forming process of the seat threads and pin threads.

Keywords: crane, fracture, pin, railway

Procedia PDF Downloads 90
5014 Comparison of Filamentous Fungus (Monascus purpureus)Growth in Submerged and Solid State Culture

Authors: Shafieeh Mansoori, Fatemeh Yazdian, Ashrafsadat Hatamian, Majid Azizi

Abstract:

Monascus purpureus, which has a special metabolite with many therapeutic and medicinal properties including antioxidant, antibiotic, anti-hypercholesterolemia, and immunosuppressive properties, is a traditional Chinese fermentation fungus and is used as a natural dietary supplement. Production of desired metabolites actually determined by optimized growth which is supported by some factors such as substrates and Monascus strains type, moisture content of the fermentation mixture, aeration, and control of contamination issues. In this experiment, M. purpureus PTCC5305 was cultured in both the liquid and solid culture medium. The former medium contain YMP (yeast extract, maltose and peptone), PGC (peptone, glucose complex), and GYP (glucose, yeast extract and peptone) medium. After 8 days, the best medium for the cell production was PGC agar medium on solid culture with 0.28 g dry weight of cell mass whereas the best liquid culture was GYP medium with 3.5 g/l dry weight of cell mass. The lowest cell production was on YMP agar with 0.1 g dry weight of cell mass and then YMP medium with 2.5 g/l dry cell weight.

Keywords: Monascus purpureus, solid state fermentation, submerged culture, Chinese fermentation fungus

Procedia PDF Downloads 393
5013 Modelling and Simulation of a Commercial Thermophilic Biogas Plant

Authors: Jeremiah L. Chukwuneke, Obiora E. Anisiji, Chinonso H. Achebe, Paul C. Okolie

Abstract:

This paper developed a mathematical model of a commercial biogas plant for urban area clean energy requirement. It identified biodegradable waste materials like domestic/city refuse as economically viable alternative source of energy. The mathematical formulation of the proposed gas plant follows the fundamental principles of thermodynamics, and further analyses were accomplished to develop an algorithm for evaluating the plant performance preferably in terms of daily production capacity. In addition, the capacity of the plant is equally estimated for a given cycle of operation and presented in time histories. A nominal 1500 m3 power gas plant was studied characteristically and its performance efficiency evaluated. It was observed that the rate of bio gas production is essentially a function of the reactor temperature, pH, substrate concentration, rate of degradation of the biomass, and the accumulation of matter in the system due to bacteria growth. The results of this study conform to a very large extent with reported empirical data of some existing plant and further model validations were conducted in line with classical records found in literature.

Keywords: energy and mass conservation, specific growth rate, thermophilic bacteria, temperature, rate of bio gas production

Procedia PDF Downloads 422
5012 Controlled Growth of Au Hierarchically Ordered Crystals Architectures for Electrochemical Detection of Traces of Molecules

Authors: P. Bauer, K. Mougin, V. Vignal, A. Buch, P. Ponthiaux, D. Faye

Abstract:

Nowadays, noble metallic nanostructures with unique morphology are widely used as new sensors due to their fascinating optical, electronic and catalytic properties. Among various shapes, dendritic nanostructures have attracted much attention because of their large surface-to-volume ratio, high sensitivity and special texture with sharp tips and nanoscale junctions. Several methods have been developed to fabricate those specific structures such as electrodeposition, photochemical way, seed-mediated growth or wet chemical method. The present study deals with a novel approach for a controlled growth pattern-directed organisation of Au flower-like crystals (NFs) deposited onto stainless steel plates to achieve large-scale functional surfaces. This technique consists in the deposition of a soft nanoporous template on which Au NFs are grown by electroplating and seed-mediated method. Size, morphology, and interstructure distance have been controlled by a site selective nucleation process. Dendritic Au nanostructures have appeared as excellent Raman-active candidates due to the presence of very sharp tips of multi-branched Au nanoparticles that leads to a large local field enhancement and a good SERS sensitivity. In addition, these structures have also been used as electrochemical sensors to detect traces of molecules present in a solution. A correlation of the number of active sites on the surface and the current charge by both colorimetric method and cyclic voltammetry of gold structures have allowed a calibration of the system. This device represents a first step for the fabrication of MEMs platform that could ultimately be integrated into a lab-on-chip system. It also opens pathways to several technologically large-scale nanomaterials fabrication such as hierarchically ordered crystal architectures for sensor applications.

Keywords: dendritic, electroplating, gold, template

Procedia PDF Downloads 172
5011 Comparison of Allelopathic Activity of Some Edible Mushroom and Wild Mushroom in Japan

Authors: Asma Osivand, Hossein Mardani, Hiroshi Araya, Yoshiharu Fujii

Abstract:

Wild mushrooms have always been considered as valuable source of bioactive compounds, while edible mushrooms have been known for their importance as food source. However, their interaction with plants through chemicals that could lead to find new biochemical have not been well undertaken. A special bioassay method (Sandwich method) was applied to compare eight common edible mushrooms (Pleurotus eryngii, Pleurotus citrinopileatus, Pleurotus ostreatus, Lentinula edodes, Grifola frondosa, Flammulina velutipes, Hypsizygus tessellatus and Pholiota namako) with some wild species (Ganoderma appelanatum, Amanita pantherina, Artomyces pyxidatus, Morchella conica, Tricholosporum porphyrophyllum, Trametes hirsuta) for their phytotoxicity against lettuce. Among all tested edible mushrooms, application of 5 mg of P. ostreatus showed stronger allelopathic activity by inhibiting the growth of radicle and hypocotyl of lettuce by 84% and 63% respectively. Moreover, same amount of T. porphyrophyllum exerted 77% and 67% growth inhibition on radicle and hypocotyl of lettuce. In general, biochemicals contributed in tested mushrooms could be the main cause for their inhibitory activity and could lead to find new allelochemicals.

Keywords: allelopathy, interaction, mushroom, phytotoxicity, Pleurotus sp., sandwich method

Procedia PDF Downloads 275