Search results for: 3D transition metal complex
7129 Environmental Impact Assessment of Ambient Particle Industrial Complex Upon Vegetation Near Settling at El-Fatyah,Libya
Authors: Ashraf M. S. Soliman, Mohsen Elhasadi
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The present study was undertaken to evaluate the impact of ambient particles emitted from an industrial complex located at El-Fatyah on growth, phytomass partitioning and accumulation, pigment content and nutrient uptake of two economically important crop species; barley (Hordeum vulgare L.Family: Poaceae) and broad bean (Vicia faba L. Family: Fabaceae) growing in the region. It was obvious from the present investigation that chlorophyll and carotenoid content showed significant responses to the industrial dust. Generally, the total pigment content of the two investigated crops in the two locations continually increased till the plant age reached 70 days after sowing then begins to decrease till the end of the growing season..The total uptake of N, P and K in the two studied species decreased in response to industrial dust in the study area compared to control location. In conclusion, barley and broad bean are very sensitive to air pollutants, and may consider as bioindicators for atmospheric pollution. Pollutants caused damage of their leaves, impair plant growth, hindered nutrient uptake and consequently limit primary productivity.Keywords: Effect of Industrial Complex on barley and broad bean
Procedia PDF Downloads 5287128 The Future of Reduced Instruction Set Computing and Complex Instruction Set Computing and Suggestions for Reduced Instruction Set Computing-V Development
Authors: Can Xiao, Ouanhong Jiang
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Based on the two instruction sets of complex instruction set computing (CISC) and reduced instruction set computing (RISC), processors developed in their respective “expertise” fields. This paper will summarize research on the differences in performance and energy efficiency between CISC and RISC and strive to eliminate the influence of peripheral configuration factors. We will discuss whether processor performance is centered around instruction sets or implementation. In addition, the rapidly developing RISC-V poses a challenge to existing models. We will analyze research results, analyze the impact of instruction sets themselves, and finally make suggestions for the development of RISC-V.Keywords: ISA, RISC-V, ARM, X86, power, energy efficiency
Procedia PDF Downloads 807127 Estimation of Source Parameters Using Source Parameters Imaging Method From Digitised High Resolution Airborne Magnetic Data of a Basement Complex
Authors: O. T. Oluriz, O. D. Akinyemi, J. A.Olowofela, O. A. Idowu, S. A. Ganiyu
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This study was carried out using aeromagnetic data which record variation in the magnitude of the earth magnetic field in order to detect local changes in the properties of the underlying geology. The aeromagnetic data (Sheet No. 261) was acquired from the archives of Nigeria Geological Survey Agency of Nigeria, obtained in 2009. The study present estimation of source parameters within an area of about 3,025 square kilometers on geographic latitude to and longitude to within Ibadan and it’s environs in Oyo State, southwestern Nigeria. The area under study belongs to part of basement complex in southwestern Nigeria. Estimation of source parameters of aeromagnetic data was achieve through the application of source imaging parameters (SPI) techniques that provide delineation, depth, dip contact, susceptibility contrast and mineral potentials of magnetic signatures within the region. The depth to the magnetic sources in the area ranges from 0.675 km to 4.48 km. The estimated depth limit to shallow sources is 0.695 km and depth to deep sources is 4.48 km. The apparent susceptibility values of the entire study area obtained ranges from 0.01 to 0.005 [SI]. This study has shown that the magnetic susceptibility within study area is controlled mainly by super paramagnetic minerals.Keywords: aeromagnetic, basement complex, meta-sediment, precambrian
Procedia PDF Downloads 4257126 Perceptions of Research Staff on the Implementation of Each-B Study: A Randomised Controlled Trial
Authors: Laila Khawaja
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In recent years, an increasing emphasis has been placed on measuring program implementation, in part because of the great variability in how complex interventions are delivered in real-life settings. There is an increased awareness that while conducting process evaluations, one should aim to identify and understand the complexities of intervention if they are to be used for future intervention development or the strategies needed to implement the same intervention in a different setting. Complex interventions are public health interventions that are not drugs or surgical procedures but have many potential active aspects of intervention. In this paper, process evaluations are aligned with MRC guidelines to identify contextual factors related to outcomes to assess the quality of implementation. This paper briefly discusses the perceptions of research team on the implementation of the intervention of ‘Engaging Adolescents in Changing Behaviour’ (EACH-B), a school-based complex intervention study aiming to improve diet and physical activity among adolescents aged 12-13 years. Through qualitative interviews and focus groups with 10 staff members, we aimed to understand their experiences and reflections on implementing the EACH-B trial delivered in 49 Schools around Hampshire, England. Data were uploaded into NVivo, and analysis was conducted using thematic analysis. The investigation revealed two overarching themes: (a) how the communication patterns with teachers were impacted during the delivery of implementation and (b) what were the team’s strategies to keep logistics aligned with the research process that impacted the overall implementation of the trial. The paper informs adaptation strategies used by the research team to establish and maintain effective communication with the teachers as well as the thoughtfulness of the team’s logistic strategy for the successful delivery of the trial.Keywords: complex interventions, process evaluation, adaptation strategies, randomised controlled trial
Procedia PDF Downloads 567125 Advanced Nanomaterials in Catalysis: Bridging the Gap Between Pollution Control and Renewable Energy
Authors: Abonyi Matthew Ndubuisi, Christopher Chiedozie Obi, Joseph Tagbo Nwabanne
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This review focuses on the application of advanced nanomaterials in catalysis for pollution control and renewable energy solutions. This review provides a comprehensive examination of the latest developments in nanocatalysts, highlighting their role in addressing environmental challenges and facilitating sustainable energy solutions. The unique properties of nanomaterials, including high surface area, tunable electronic properties, and enhanced reactivity, make them ideal candidates for catalytic applications. This review explores various types of nanomaterials, such as metal nanoparticles, carbon-based nanostructures, and metal-organic frameworks, and their effectiveness in processes like photocatalysis, electrocatalysis, and hydrogen production. Additionally, the review discusses the environmental benefits of using nanocatalysts in pollution control, focusing on the degradation of pollutants in water and air. The potential of these materials to bridge the gap between environmental remediation and clean energy production is emphasized, showcasing their dual role in mitigating pollution and advancing renewable energy technologies. In conclusion, the review analyzes the current challenges and future directions in the field, highlighting the need for continued research to improve the design and application of nanocatalysts for a sustainable future.Keywords: nanomaterials, catalysis, pollution control, renewable energy, sustainable technology
Procedia PDF Downloads 57124 Synthesis, Characterization and Biological Activites of Azomethine Derivatives
Authors: Lynda Golea, Rachid Chebaki
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Schiff bases contain heterocyclic structural units with N and O donor atoms which plays an important role in coordination chemistry. Azomethine groups are a broad class of widely used compounds with applications in many fields, including analytical, inorganic chemistry and biological. Schiff's base is of promising research interest due to the widespread antibacterial resistance in medical science. In addition, the research is essential to generate Schiff base metal complexes with various applications. Schiff complexes have been used as drugs and have antibacterial, antifungal, antiviral, and anti-inflammatory properties. The various donor atoms they contain offer a special ability for metal binding. In this research on the physicochemical properties of azomethine groups, we synthesized and studied the Schiff base compounds by a condensation reaction of tryptamines and acetophenone in ethanol. The structure of the prepared compound was interpreted using 1H NMR, 13C NMR, UV-vis and FT-IR. A computational analysis at the level of DFT with functional B3LYP in conjunction with the base 6-311+G (d, p) was conducted to study its electronic and molecular structure. The biological study was performed on three bacterial strains usually causing infection, including Gram-positive and Gram-negative, for antibacterial activity. Results showed moderate biological activity and proportional activity with increasing concentration.Keywords: azomethine, HOMO, LUMO, RMN, molecular docking
Procedia PDF Downloads 547123 Finite Element Method for Modal Analysis of FGM
Authors: S. J. Shahidzadeh Tabatabaei, A. M. Fattahi
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Modal analysis of a FGM plate containing the ceramic phase of Al2O3 and metal phase of stainless steel 304 was performed using ABAQUS, with the assumptions that the material has an elastic mechanical behavior and its Young modulus and density are varying in thickness direction. For this purpose, a subroutine was written in FOTRAN and linked with ABAQUS. First, a simulation was performed in accordance to other researcher’s model, and then after comparing the obtained results, the accuracy of the present study was verified. The obtained results for natural frequency and mode shapes indicate good performance of user-written subroutine as well as FEM model used in present study. After verification of obtained results, the effect of clamping condition and the material type (i.e. the parameter n) was investigated. In this respect, finite element analysis was carried out in fully clamped condition for different values of n. The results indicate that the natural frequency decreases with increase of n, since with increase of n, the amount of ceramic phase in FGM plate decreases, while the amount of metal phase increases, leading to decrease of the plate stiffness and hence, natural frequency, as the Young modulus of Al2O3 is equal to 380 GPa and the Young modulus of stainless steel 304 is equal to 207 GPa.Keywords: FGM plates, modal analysis, natural frequency, finite element method
Procedia PDF Downloads 3117122 Study of the Possibility of Adsorption of Heavy Metal Ions on the Surface of Engineered Nanoparticles
Authors: Antonina A. Shumakova, Sergey A. Khotimchenko
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The relevance of research is associated, on the one hand, with an ever-increasing volume of production and the expansion of the scope of application of engineered nanomaterials (ENMs), and on the other hand, with the lack of sufficient scientific information on the nature of the interactions of nanoparticles (NPs) with components of biogenic and abiogenic origin. In particular, studying the effect of ENMs (TiO2 NPs, SiO2 NPs, Al2O3 NPs, fullerenol) on the toxicometric characteristics of common contaminants such as lead and cadmium is an important hygienic task, given the high probability of their joint presence in food products. Data were obtained characterizing a multidirectional change in the toxicity of model toxicants when they are co-administered with various types of ENMs. One explanation for this fact is the difference in the adsorption capacity of ENMs, which was further studied in in vitro studies. For this, a method was proposed based on in vitro modeling of conditions simulating the environment of the small intestine. It should be noted that the obtained data are in good agreement with the results of in vivo experiments: - with the combined administration of lead and TiO2 NPs, there were no significant changes in the accumulation of lead in rat liver; in other organs (kidneys, spleen, testes and brain), the lead content was lower than in animals of the control group; - studying the combined effect of lead and Al2O3 NPs, a multiple and significant increase in the accumulation of lead in rat liver was observed with an increase in the dose of Al2O3 NPs. For other organs, the introduction of various doses of Al2O3 NPs did not significantly affect the bioaccumulation of lead; - with the combined administration of lead and SiO2 NPs in different doses, there was no increase in lead accumulation in all studied organs. Based on the data obtained, it can be assumed that at least three scenarios of the combined effects of ENMs and chemical contaminants on the body: - ENMs quite firmly bind contaminants in the gastrointestinal tract and such a complex becomes inaccessible (or inaccessible) for absorption; in this case, it can be expected that the toxicity of both ENMs and contaminants will decrease; - the complex formed in the gastrointestinal tract has partial solubility and can penetrate biological membranes and / or physiological barriers of the body; in this case, ENMs can play the role of a kind of conductor for contaminants and, thus, their penetration into the internal environment of the body increases, thereby increasing the toxicity of contaminants; - ENMs and contaminants do not interact with each other in any way, therefore the toxicity of each of them is determined only by its quantity and does not depend on the quantity of another component. Authors hypothesized that the degree of adsorption of various elements on the surface of ENMs may be a unique characteristic of their action, allowing a more accurate understanding of the processes occurring in a living organism.Keywords: absorption, cadmium, engineered nanomaterials, lead
Procedia PDF Downloads 827121 Preparation and Evaluation of Poly(Ethylene Glycol)-B-Poly(Caprolactone) Diblock Copolymers with Zwitterionic End Group for Thermo-Responsive Properties
Authors: Bo Keun Lee, Doo Yeon Kwon, Ji Hoon Park, Gun Hee Lee, Ji Hye Baek, Heung Jae Chun, Young Joo Koh, Moon Suk Kim
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Thermo-responsive materials are viscoelastic materials that undergo a sol-to-gel phase transition at a specific temperature and many materials have been developed. MPEG-b-PCL (MPC) as a thermo-responsive material contained hydrophilic and hydrophobic segments and it formed an ordered crystalline structure of hydrophobic PCL segments in aqueous solutions. The ordered crystalline structure packed tightly or aggregated and finally induced an aggregated gel through intra- and inter-molecular interactions as a function of temperature. Thus, we introduced anionic and cationic groups into the end positions of the PCL chain to alter the hydrophobicity of the PCL segment. Introducing anionic and cationic groups into the PCL end position altered their solubility by changing the crystallinity and hydrophobicity of the PCL block domains. These results indicated that the properties of the end group in the hydrophobic PCL blockand the balance between hydrophobicity and hydrophilicity affect thermo-responsivebehavior of the copolymers in aqueous solutions. Thus, we concluded that determinant of the temperature-dependent thermo-responsive behavior of MPC depend on the ionic end group in the PCL block. So, we introduced zwitterionic end groups to investigate the thermo-responsive behavior of MPC. Methoxypoly(ethylene oxide) and ε-caprolactone (CL) were randomly copolymerized that introduced varying hydrophobic PCL lengths and an MPC featuring a zwitterionic sulfobetaine (MPC-ZW) at the chain end of the PCL segment. The MPC and MPC-ZW copolymers were obtained formed sol-state at room temperature when prepared as 20-wt% aqueous solutions. The solubility of MPC decreased when the PCL block was increased from molecular weight. The solubilization time of MPC-2.4k was around 20 min and MPC-2.8k, MPC-3.0k increased to 30 min and 1 h, respectively. MPC-3.6k was not solubilized. In case of MPC-ZW 3.6k, However, the zwitterion-modified MPC copolymers were solubilized in 3–5 min. This result indicates that the zwitterionic end group of the MPC-ZW diblock copolymer increased the aqueous solubility of the diblock copolymer even when the length of the hydrophobic PCL segment was increased. MPC and MPC-ZW diblock copolymers that featuring zwitterionic end groups were synthesized successfully. The sol-to-gel phase-transition was formed that specific temperature depend on the length of the PCL hydrophobic segments introduced and on the zwitterion groups attached to the MPC chain end. This result indicated that the zwitterionic end groups reduced the hydrophobicity in the PCL block and changed the solubilization. The MPC-ZW diblock copolymer can be utilized as a potential injectable drug and cell carrier.Keywords: thermo-responsive material, zwitterionic, hydrophobic, crystallization, phase transition
Procedia PDF Downloads 4987120 Lung Function, Urinary Heavy Metals And ITS Other Influencing Factors Among Community In Klang Valley
Authors: Ammar Amsyar Abdul Haddi, Mohd Hasni Jaafar
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Heavy metals are elements naturally presented in the environment that can cause adverse effect to health. But not much literature was found on effects toward lung function, where impairment of lung function may lead to various lung diseases. The objective of the study is to explore the lung function impairment, urinary heavy metal level, and its associated factors among the community in Klang valley, Malaysia. Sampling was done in Kuala Lumpur suburb public and housing areas during community events throughout March 2019 till October 2019. respondents who gave the consent were given a questionnaire to answer and was proceeded with a lung function test. Urine samples were obtained at the end of the session and sent for Inductively coupled plasma mass spectrometry (ICP-MS) analysis for heavy metal cadmium (Cd) and lead (Pb) concentration. A total of 200 samples were analysed, and of all, 52% of respondents were male, Age ranging from 18 years old to 74 years old with a mean age of 38.44. Urinary samples show that 12% of the respondent (n=22) has Cd level above than average, and 1.5 % of the respondent (n=3) has urinary Pb at an above normal level. Bivariate analysis show that there was a positive correlation between urinary Cd and urinary Pb (r= 0.309; p<0.001). Furthermore, there was a negative correlation between urinary Cd level and full vital capacity (FVC) (r=-0.202, p=0.004), Force expiratory volume at 1 second (FEV1) (r = -0.225, p=0.001), and also with Force expiratory flow between 25-75% FVC (FEF25%-75%) (r= -0.187, p=0.008). however, urinary Pb did not show any association with FVC, FEV1, FEV1/FVC, or FEF25%-75%. Multiple linear regression analysis shows that urinary Cd remained significant and negatively affect FVC% (p=0.025) and FEV1% (p=0.004) achieved from the predicted value. On top of that, other factors such as education level (p=0.013) and duration of smoking(p=0.003) may influencing both urinary Cd and performance in lung function as well, suggesting Cd as a potential mediating factor between smoking and impairment of lung function. however, there was no interaction detected between heavy metal or other influencing factor in this study. In short, there is a negative linear relationship detected between urinary Cd and lung function, and urinary Cd is likely to affects lung function in a restrictive pattern. Since smoking is also an influencing factor for urinary Cd and lung function impairment, it is highly suggested that smokers should be screened for lung function and urinary Cd level in the future for early disease prevention.Keywords: lung function, heavy metals, community
Procedia PDF Downloads 1487119 India’s Energy System Transition, Survival of the Greenest
Authors: B. Sudhakara Reddy
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The transition to a clean and green energy system is an economic and social transformation that is exciting as well as challenging. The world today faces a formidable challenge in transforming its economy from being driven primarily by fossil fuels, which are non-renewable and a major source of global pollution, to becoming an economy that can function effectively using renewable energy sources and by achieving high energy efficiency levels. In the present study, a green economy scenario is developed for India using a bottom-up approach. The results show that the penetration rate of renewable energy resources will reduce the total primary energy demand by 23% under GE. Improvements in energy efficiency (e.g. households, industrial and commercial sectors) will result in reduced demand to the tune of 318 MTOE. The volume of energy-related CO2 emissions decline to 2,218 Mt in 2030 from 3,440 under the BAU scenario and the per capita emissions will reduce by about 35% (from 2.22 to 1.45) under the GE scenario. The reduction in fossil fuel demand and focus on clean energy will reduce the energy intensity to 0.21 (TOE/US$ of GDP) and carbon intensity to 0.42 (ton/US$ of GDP) under the GE scenario. total import bill (coal and oil) will amount to US$ 334 billion by 2030 (at 2010/11 prices), but as per the GE scenario, it would be US$ 194.2 billion, a saving of about US$ 140 billion. The building of a green energy economy can also serve another purpose: to develop new ‘pathways out of poverty’ by creating more than 10 million jobs and thus raise the standard of living of low-income people. The differences between the baseline and green energy scenarios are not so much the consequence of the diffusion of various technologies. It is the result of the active roles of different actors and the drivers that become dominant.Keywords: emissions, green energy, fossil fuels, green jobs, renewables, scenario
Procedia PDF Downloads 5297118 Qualitative Profiling in Practice: The Italian Public Employment Services Experience
Authors: L. Agneni, F. Carta, C. Micheletta, V. Tersigni
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The development of a qualitative method to profile jobseekers is needed to improve the quality of the Public Employment Services (PES) in Italy. This is why the National Agency for Active Labour Market Policies (ANPAL) decided to introduce a Qualitative Profiling Service in the context of the activities carried out by local employment offices’ operators. The qualitative profiling service provides information and data regarding the jobseeker’s personal transition status, through a semi-structured questionnaire administered to PES clients during the guidance interview. The questionnaire responses allow PES staff to identify, for each client, proper activities and policy measures to support jobseekers in their reintegration into the labour market. Data and information gathered by the qualitative profiling tool are the following: frequency, modalities and motivations for clients to apply to local employment offices; clients’ expectations and skills; difficulties that they have faced during the previous working experiences; strategies, actions undertaken and activated channels for job search. These data are used to assess jobseekers’ personal and career characteristics and to measure their employability level (qualitative profiling index), in order to develop and deliver tailor-made action programmes for each client. This paper illustrates the use of the above-mentioned qualitative profiling service on the national territory and provides an overview of the main findings of the survey: concerning the difficulties that unemployed people face in finding a job and their perception of different aspects related to the transition in the labour market. The survey involved over 10.000 jobseekers registered with the PES. Most of them are beneficiaries of the “citizens' income”, a specific active labour policy and social inclusion measure. Furthermore, data analysis allows classifying jobseekers into a specific group of clients with similar features and behaviours, on the basis of socio-demographic variables, customers' expectations, needs and required skills for the profession for which they seek employment. Finally, the survey collects PES staff opinions and comments concerning clients’ difficulties in finding a new job and also their strengths. This is a starting point for PESs’ operators to define adequate strategies to facilitate jobseekers’ access or reintegration into the labour market.Keywords: labour market transition, public employment services, qualitative profiling, vocational guidance
Procedia PDF Downloads 1287117 An Investigation into Slow ESL Reading Speed in Pakistani Students
Authors: Hina Javed
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This study investigated the different strategies used by Pakistani students learning English as a second language at secondary level school. The basic premise of the study is that ESL students face tremendous difficulty while they are reading a text in English. It also purports to dig into the different causes of their slow reading. They might range from word reading accuracy, mental translation, lexical density, cultural gaps, complex syntactic constructions, and back skipping. Sixty Grade 7 students from two secondary mainstream schools in Lahore were selected for the study, thirty being boys and thirty girls. They were administered reading-related and reading speed pre and post-tests. The purpose of the tests was to gauge their performance on different reading tasks so as to be able to see how they used strategies, if any, and also to ascertain the causes hampering their performance on those tests. In the pretests, they were given simple texts with considerable lexical density and moderately complex sentential layout. In the post-tests, the reading tasks contained comic strips, texts with visuals, texts with controlled vocabulary, and an evenly distributed varied range of simple, compound, and complex sentences. Both the tests were timed. The results gleaned through the data gathered corroborated the researchers’ basic hunch that they performed significantly better than pretests. The findings suggest that the morphological structure of words and lexical density are the main sources of reading comprehension difficulties in poor ESL readers. It is also confirmed that if the texts are accompanied by pictorial visuals, it greatly facilitates students’ reading speed and comprehension. There is no substantial evidence that ESL readers adopt any specific strategy while reading in English.Keywords: slow ESL reading speed, mental translation, complex syntactic constructions, back skipping
Procedia PDF Downloads 657116 Separation of Copper(II) and Iron(III) by Solvent Extraction and Membrane Processes with Ionic Liquids as Carriers
Authors: Beata Pospiech
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Separation of metal ions from aqueous solutions is important as well as difficult process in hydrometallurgical technology. This process is necessary for obtaining of clean metals. Solvent extraction and membrane processes are well known as separation methods. Recently, ionic liquids (ILs) are very often applied and studied as extractants and carriers of metal ions from aqueous solutions due to their good extractability properties for various metals. This work discusses a method to separate copper(II) and iron(III) from hydrochloric acid solutions by solvent extraction and transport across polymer inclusion membranes (PIM) with the selected ionic liquids as extractants/ion carriers. Cyphos IL 101 (trihexyl(tetradecyl)phosphonium chloride), Cyphos IL 104 (trihexyl(tetradecyl)phosphonium bis(2,4,4 trimethylpentyl)phosphi-nate), trioctylmethylammonium thiosalicylate [A336][TS] and trihexyl(tetradecyl)phosphonium thiosalicylate [PR4][TS] were used for the investigations. Effect of different parameters such as hydrochloric acid concentration in aqueous phase on iron(III) and copper(II) extraction has been investigated. Cellulose triacetate membranes with the selected ionic liquids as carriers have been prepared and applied for transport of iron(IIII) and copper(II) from hydrochloric acid solutions.Keywords: copper, iron, ionic liquids, solvent extraction
Procedia PDF Downloads 2717115 Electromagnetic Source Direction of Arrival Estimation via Virtual Antenna Array
Authors: Meiling Yang, Shuguo Xie, Yilong Zhu
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Nowadays, due to diverse electric products and complex electromagnetic environment, the localization and troubleshooting of the electromagnetic radiation source is urgent and necessary especially on the condition of far field. However, based on the existing DOA positioning method, the system or devices are complex, bulky and expensive. To address this issue, this paper proposes a single antenna radiation source localization method. A single antenna moves to form a virtual antenna array combined with DOA and MUSIC algorithm to position accurately, meanwhile reducing the cost and simplify the equipment. As shown in the results of simulations and experiments, the virtual antenna array DOA estimation modeling is correct and its positioning is credible.Keywords: virtual antenna array, DOA, localization, far field
Procedia PDF Downloads 3617114 Experimental Analysis of Structure Borne Noise in an Enclosure
Authors: Waziralilah N. Fathiah, A. Aminudin, U. Alyaa Hashim, T. Vikneshvaran D. Shakirah Shukor
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This paper presents the experimental analysis conducted on a structure borne noise in a rectangular enclosure prototype made by joining of sheet aluminum metal and plywood. The study is significant as many did not realized the annoyance caused by structural borne-noise. In this study, modal analysis is carried out to seek the structure’s behaviour in order to identify the characteristics of enclosure in frequency domain ranging from 0 Hz to 200 Hz. Here, numbers of modes are identified and the characteristic of mode shape is categorized. Modal experiment is used to diagnose the structural behaviour while microphone is used to diagnose the sound. Spectral testing is performed on the enclosure. It is acoustically excited using shaker and as it vibrates, the vibrational and noise responses sensed by tri-axis accelerometer and microphone sensors are recorded respectively. Experimental works is performed on each node lies on the gridded surface of the enclosure. Both experimental measurement is carried out simultaneously. The modal experimental results of the modal modes are validated by simulation performed using MSC Nastran software. In pursuance of reducing the structure borne-noise, mitigation method is used whereby the stiffener plates are perpendicularly placed on the sheet aluminum metal. By using this method, reduction in structure borne-noise is successfully made at the end of the study.Keywords: enclosure, modal analysis, sound analysis, structure borne-noise
Procedia PDF Downloads 4247113 Characterization of Two Hybrid Welding Techniques on SA 516 Grade 70 Weldments
Authors: M. T. Z. Butt, T. Ahmad, N. A. Siddiqui
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Commercially SA 516 Grade 70 is frequently used for the manufacturing of pressure vessels, boilers and storage tanks etc. in fabrication industry. Heat input is the major parameter during welding that may bring significant changes in the microstructure as well as the mechanical properties. Different welding technique has different heat input rate per unit surface area. Materials with large thickness are dealt with different combination of welding techniques to achieve required mechanical properties. In the present research two schemes: Scheme 1: SMAW (Shielded Metal Arc Welding) & GTAW (Gas Tungsten Arc Welding) and Scheme 2: SMAW & SAW (Submerged Arc Welding) of hybrid welding techniques have been studied. The purpose of these schemes was to study hybrid welding effect on the microstructure and mechanical properties of the weldment, heat affected zone and base metal area. It is significant to note that the thickness of base plate was 12 mm, also welding conditions and parameters were set according to ASME Section IX. It was observed that two different hybrid welding techniques performed on two different plates demonstrated that the mechanical properties of both schemes are more or less similar. It means that the heat input, welding techniques and varying welding operating conditions & temperatures did not make any detrimental effect on the mechanical properties. Hence, the hybrid welding techniques mentioned in the present study are favorable to implicate for the industry using the plate thickness around 12 mm thick.Keywords: grade 70, GTAW, hybrid welding, SAW, SMAW
Procedia PDF Downloads 3347112 Fe3O4 Decorated ZnO Nanocomposite Particle System for Waste Water Remediation: An Absorptive-Photocatalytic Based Approach
Authors: Prateek Goyal, Archini Paruthi, Superb K. Misra
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Contamination of water resources has been a major concern, which has drawn attention to the need to develop new material models for treatment of effluents. Existing conventional waste water treatment methods remain ineffective sometimes and uneconomical in terms of remediating contaminants like heavy metal ions (mercury, arsenic, lead, cadmium and chromium); organic matter (dyes, chlorinated solvents) and high salt concentration, which makes water unfit for consumption. We believe that nanotechnology based strategy, where we use nanoparticles as a tool to remediate a class of pollutants would prove to be effective due to its property of high surface area to volume ratio, higher selectivity, sensitivity and affinity. In recent years, scientific advancement has been made to study the application of photocatalytic (ZnO, TiO2 etc.) nanomaterials and magnetic nanomaterials in remediating contaminants (like heavy metals and organic dyes) from water/wastewater. Our study focuses on the synthesis and monitoring remediation efficiency of ZnO, Fe3O4 and Fe3O4 coated ZnO nanoparticulate system for the removal of heavy metals and dyes simultaneously. Multitude of ZnO nanostructures (spheres, rods and flowers) using multiple routes (microwave & hydrothermal approach) offers a wide range of light active photo catalytic property. The phase purity, morphology, size distribution, zeta potential, surface area and porosity in addition to the magnetic susceptibility of the particles were characterized by XRD, TEM, CPS, DLS, BET and VSM measurements respectively. Further on, the introduction of crystalline defects into ZnO nanostructures can also assist in light activation for improved dye degradation. Band gap of a material and its absorbance is a concrete indicator for photocatalytic activity of the material. Due to high surface area, high porosity and affinity towards metal ions and availability of active surface sites, iron oxide nanoparticles show promising application in adsorption of heavy metal ions. An additional advantage of having magnetic based nanocomposite is, it offers magnetic field responsive separation and recovery of the catalyst. Therefore, we believe that ZnO linked Fe3O4 nanosystem would be efficient and reusable. Improved photocatalytic efficiency in addition to adsorption for environmental remediation has been a long standing challenge, and the nano-composite system offers the best of features which the two individual metal oxides provide for nanoremediation.Keywords: adsorption, nanocomposite, nanoremediation, photocatalysis
Procedia PDF Downloads 2347111 Changes in Inorganic Element Contents in Potamogeton Natans Exposed to Cement Factory Pollution
Authors: Yavuz Demir, Mucip Genisel, Hulya Turk, Turgay Sisman, Serkan Erdal
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In this study, the changes in contents of inorganic elements in the aquatic plant (Potamogeton natans) as a reflection of the impact of chemical nature pollution in a cement factory region (CFR) was evaluated. For this purpose, P, S, K, Ca, Fe, Cl, Mn, Cu, Zn, Mo, Ni, Si, Al, and Cd concentrations were measured in the aquatic plant (Potamogeton natans) taken from a CFR. As a control, aquatic plant was collected at a distance of 2000 m from the outer zone of the cement factory. Inorganic element compositions were measured by energy dispersive X-ray fluorescence spectrometry (EDXRF). Three aquatic plant exhibited similar changes in contents of microelements and macroelements in their leaves. P, S, K, Cl, Ca, and Mo contents in plant grown in the CFR were reduced significantly compared to control plant, whereas their contents of Al, Mn, Fe, Ni, Cu, Zn and Cd were very high. According to these findings, it is possible that aquatic plant (Potamogeton natans) inhabiting in the vicinity of cement factory sustains the deficiency of important essential elements like P, S, K, Ca, and Mo and greatly accumulate heavy metals like Al, Mn, Fe, Ni, Cu, Zn, and Cd. In addition, results of water analysis showed that heavy metal content such as Cu, Pb, Zn, Co, and Al of water taken from CFR was remarkably high than that of outer zone of CFR. These findings with relation to changes in inorganic composition can contribute to be elucidated of effect mechanism on growth and development of aquatic plant (Potamogeton natans) of pollution resulted from cement factories.Keywords: aquatic plant, cement factory, heavy metal pollution, inorganic element, Potamogeton natans
Procedia PDF Downloads 2627110 A Tuning Method for Microwave Filter via Complex Neural Network and Improved Space Mapping
Authors: Shengbiao Wu, Weihua Cao, Min Wu, Can Liu
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This paper presents an intelligent tuning method of microwave filter based on complex neural network and improved space mapping. The tuning process consists of two stages: the initial tuning and the fine tuning. At the beginning of the tuning, the return loss of the filter is transferred to the passband via the error of phase. During the fine tuning, the phase shift caused by the transmission line and the higher order mode is removed by the curve fitting. Then, an Cauchy method based on the admittance parameter (Y-parameter) is used to extract the coupling matrix. The influence of the resonant cavity loss is eliminated during the parameter extraction process. By using processed data pairs (the amount of screw variation and the variation of the coupling matrix), a tuning model is established by the complex neural network. In view of the improved space mapping algorithm, the mapping relationship between the actual model and the ideal model is established, and the amplitude and direction of the tuning is constantly updated. Finally, the tuning experiment of the eight order coaxial cavity filter shows that the proposed method has a good effect in tuning time and tuning precision.Keywords: microwave filter, scattering parameter, coupling matrix, intelligent tuning
Procedia PDF Downloads 2927109 The Depth Penetration of Beryllium-7, ⁷BE as a Tracer in the Sembrong Catchment Area Study
Authors: J. Sharib, D. N. A. Tugi, M. T. Ishak, M. I. A. Adziz
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The main purpose of this research paper conducted was to study the penetration of ⁷Be onto the soil surface for two different seasons in different areas of agricultural activity. The study was conducted during the dry and wet seasons from January to May 2019 in the Sembrong catchment area. The Sembrong Catchment Area is located in the district of Kluang, Johor in the South of Peninsular Malaysia and was selected based on the small size of the catchment and surrounded by various agricultural activities. A total of twenty (20) core soil samples to a depth of 10 cm each were taken using a metal corer made of metal. All these samples were brought to the Radiochemistry and Environment Group (RAS), Nuclear Malaysia, Block 23, Bangi, Malaysia, to enable the preparation, drying and analysis work to be carried out. Furthermore, all samples were oven dried at 45 – 60 ºC so that the dry weight became constant and gently disaggregated. Lastly, dried samples were milled and sieved at 2 mm before being packed into a well-type container and ready for ⁷Be analysis. The result of the analysis shows that the penetration of ⁷Be into the soil surface decreases by an exponential decay. The distribution of profiles to the interior of the soil surface or ho values ranged from 1.56 to 3.62 kg m⁻² and from 2.59 to 4.17 kg m⁻² for both dry and wet seasons. Consequently, the dry season has given a lower ho value when compared to the wet season. In conclusion, ⁷Be is a very suitable tracer to be used in determining the penetration onto the soil surface or ho values for the two different seasons.Keywords: depth penetration, dry season, wet season, sembrong catchment, well type container
Procedia PDF Downloads 1177108 Meeting the Energy Balancing Needs in a Fully Renewable European Energy System: A Stochastic Portfolio Framework
Authors: Iulia E. Falcan
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The transition of the European power sector towards a clean, renewable energy (RE) system faces the challenge of meeting power demand in times of low wind speed and low solar radiation, at a reasonable cost. This is likely to be achieved through a combination of 1) energy storage technologies, 2) development of the cross-border power grid, 3) installed overcapacity of RE and 4) dispatchable power sources – such as biomass. This paper uses NASA; derived hourly data on weather patterns of sixteen European countries for the past twenty-five years, and load data from the European Network of Transmission System Operators-Electricity (ENTSO-E), to develop a stochastic optimization model. This model aims to understand the synergies between the four classes of technologies mentioned above and to determine the optimal configuration of the energy technologies portfolio. While this issue has been addressed before, it was done so using deterministic models that extrapolated historic data on weather patterns and power demand, as well as ignoring the risk of an unbalanced grid-risk stemming from both the supply and the demand side. This paper aims to explicitly account for the inherent uncertainty in the energy system transition. It articulates two levels of uncertainty: a) the inherent uncertainty in future weather patterns and b) the uncertainty of fully meeting power demand. The first level of uncertainty is addressed by developing probability distributions for future weather data and thus expected power output from RE technologies, rather than known future power output. The latter level of uncertainty is operationalized by introducing a Conditional Value at Risk (CVaR) constraint in the portfolio optimization problem. By setting the risk threshold at different levels – 1%, 5% and 10%, important insights are revealed regarding the synergies of the different energy technologies, i.e., the circumstances under which they behave as either complements or substitutes to each other. The paper concludes that allowing for uncertainty in expected power output - rather than extrapolating historic data - paints a more realistic picture and reveals important departures from results of deterministic models. In addition, explicitly acknowledging the risk of an unbalanced grid - and assigning it different thresholds - reveals non-linearity in the cost functions of different technology portfolio configurations. This finding has significant implications for the design of the European energy mix.Keywords: cross-border grid extension, energy storage technologies, energy system transition, stochastic portfolio optimization
Procedia PDF Downloads 1577107 Application of Regularized Spatio-Temporal Models to the Analysis of Remote Sensing Data
Authors: Salihah Alghamdi, Surajit Ray
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Space-time data can be observed over irregularly shaped manifolds, which might have complex boundaries or interior gaps. Most of the existing methods do not consider the shape of the data, and as a result, it is difficult to model irregularly shaped data accommodating the complex domain. We used a method that can deal with space-time data that are distributed over non-planner shaped regions. The method is based on partial differential equations and finite element analysis. The model can be estimated using a penalized least squares approach with a regularization term that controls the over-fitting. The model is regularized using two roughness penalties, which consider the spatial and temporal regularities separately. The integrated square of the second derivative of the basis function is used as temporal penalty. While the spatial penalty consists of the integrated square of Laplace operator, which is integrated exclusively over the domain of interest that is determined using finite element technique. In this paper, we applied a spatio-temporal regression model with partial differential equations regularization (ST-PDE) approach to analyze a remote sensing data measuring the greenness of vegetation, measure by an index called enhanced vegetation index (EVI). The EVI data consist of measurements that take values between -1 and 1 reflecting the level of greenness of some region over a period of time. We applied (ST-PDE) approach to irregular shaped region of the EVI data. The approach efficiently accommodates the irregular shaped regions taking into account the complex boundaries rather than smoothing across the boundaries. Furthermore, the approach succeeds in capturing the temporal variation in the data.Keywords: irregularly shaped domain, partial differential equations, finite element analysis, complex boundray
Procedia PDF Downloads 1337106 Zinc Sorption by Six Agricultural Soils Amended with Municipal Biosolids
Authors: Antoine Karam, Lotfi Khiari, Bruno Breton, Alfred Jaouich
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Anthropogenic sources of zinc (Zn), including industrial emissions and effluents, Zn–rich fertilizer materials and pesticides containing Zn, can contribute to increasing the concentration of soluble Zn at levels toxic to plants in acid sandy soils. The application of municipal sewage sludge or biosolids (MBS) which contain metal immobilizing agents on coarse-textured soils could improve the metal sorption capacity of the low-CEC soils. The purpose of this experiment was to evaluate the sorption of Zn in surface samples (0-15 cm) of six Quebec (Canada) soils amended with MBS (pH 6.9) from Val d’Or (Quebec, Canada). Soil samples amended with increasing amounts (0 to 20%) of MBS were equilibrated with various amounts of Zn as ZnCl2 in 0.01 M CaCl2 for 48 hours at room temperature. Sorbed Zn was calculated from the difference between the initial and final Zn concentration in solution. Zn sorption data conformed to the linear form of Freundlich equation. The amount of sorbed Zn increased considerably with increasing MBS rate. Analysis of variance revealed a highly significant effect (p ≤ 0.001) of soil texture and MBS rate on the amount of sorbed Zn. The average values of the Zn-sorption capacity of MBS-amended coarse-textured soils were lower than those of MBS-amended fine textured soils. The two sandy soils (86-99% sand) amended with MBS retained 2- to 5-fold Zn than those without MBS (control). Significant Pearson correlation coefficients between the Zn sorption isotherm parameter, i.e. the Freundlich sorption isotherm (KF), and commonly measured physical and chemical entities were obtained. Among all the soil properties measured, soil pH gave the best significant correlation coefficients (p ≤ 0.001) for soils receiving 0, 5 and 10% MBS. Furthermore, KF values were positively correlated with soil clay content, exchangeable basic cations (Ca, Mg or K), CEC and clay content to CEC ratio. From these results, it can be concluded that (i) municipal biosolids provide sorption sites that have a strong affinity for Zn, (ii) both soil texture, especially clay content, and soil pH are the main factors controlling anthropogenic Zn sorption in the municipal biosolids-amended soils, and (iii) the effect of municipal biosolids on Zn sorption will be more pronounced for a sandy soil than for a clay soil.Keywords: metal, recycling, sewage sludge, trace element
Procedia PDF Downloads 2737105 The Social Construction of Diagnosis: An Exploratory Study on Gender Dysphoria and Its Implications on Personal Narratives
Authors: Jessica Neri, Elena Faccio
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In Europe, except for Denmark and Malta, the legal gender change and the stages of the possible process of gender transition are bound to the diagnosis of a gender identity disorder. The requirement of the evaluation of a mental disorder might have many implications on trans people’s self-representations, interpersonal relations in different social contexts and the therapeutic relations with clinicians during the transition. Psychopathological language may contribute to define the individual’s reality from normative presuppositions with value implications related to the dominant cultural principles. In an effort to mark the boundaries between sanity and pathology, it concurs to the definition of the management procedures of the constructed diversities and deviances, legitimizing the operational practices of particular professional figures. The aim of this research concerns the analysis of the diagnostic category of gender dysphoria contained in the last edition of the Diagnostic and Statistical Manual of Mental Disorders. In particular, this study focuses on the relationship between the implicit and explicit assumptions related to the expressions of gender non-conformity, that sustain the language and the criteria characterizing the Manual, and the possible implications on people’s narratives of transition. In order to achieve this objective two main research methods were used: historical reconstruction of the diagnostic category in the different versions of the Manual and content analysis of that category in the present version. From the historical analysis, in the medical and psychiatric field gender non-conformity has been predominantly explicated by naturalistic perspectives, naming it ‘transsexualism’ and collocating it in the category of gender identity disorder. Currently, pathological judged experiences are represented by gender dysphoria, described in the DSM-5 as the distress that may accompany the incongruence between one's experienced or expressed gender and one's assigned gender, specifying that there must be ‘evidence’ of this. Implicit theories about gender binary, parallelism between gender identity, sex and sexuality and the understanding of the mental health and the subject’s agency as subordinated to the expert knowledge, can be found in the process of designation of the category. A lack of awareness of the historical, social and political aspects connected to the cultural and normative dimensions at the basis of these implicit theories, can be noticed and data given by culture and data given by supposed -biological or psychological- nature, are often confused. This reductionist interpretation of gender and its presumed diversities legitimize the clinician to assume the role of searching and orienting, in a correctional perspective, the biographical elements that correspond to him specific expectations, with no space for other possibilities and identity configurations for people in transition. This research may contribute to the current critical debate about the epistemological foundation of the psychodiagnosis, emphasizing the pragmatic effects on the individuals and on the psychological practice in its wider social context. This work also permits to underline the risks due to the lack of awareness of the processes of social construction of the diagnostic system and its essential role of defence of the values that hold up the symbolic universe of reference.Keywords: diagnosis, gender dysphoria, narratives, social constructionism
Procedia PDF Downloads 2227104 High Temperature Properties of Diffusion Brazed Joints of in 939 Ni-Base Superalloy
Authors: Hyunki Kang, Hi Won Jeong
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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 387103 Impact of Tryptic Limited Hydrolysis on Bambara Protein-Gum Arabic Soluble Complexes Formation
Authors: Abiola A. Ojesanmi, Eric O. Amonsou
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The formation of soluble complexes is usually within a narrow pH range characterized by weak interactions. Moreover, the rigid conformation of globular proteins restricts the number of charged groups capable of interacting with polysaccharides, thereby limiting food applications. Hence, this study investigated the impact of tryptic-limited hydrolysis on the formation of Bambara protein-gum arabic soluble complexes formation. The electrostatic interactions were monitored through turbidimetry analysis. The Bambara protein hydrolysates at a specified degree of hydrolysis, and DHs (2, 5, and 7.5) were characterized using size exclusion chromatography, zeta potential, surface hydrophobicity, and intrinsic fluorescence. The stability of the complexes was investigated using differential scanning calorimetry and rheometry. The limited tryptic hydrolysis significantly widened the pH range of the formation of soluble complexes, with DH 5 having a wider range (pH 7.0 - 4.3) compared to DH 2 and DH 7.5, while there was no notable difference in the optimum complexation pH of the insoluble complexes. Larger peptides (140, 118 kDa) were detected in DH 2 relative to 144, 70, and 61 kDa in DH 5, which were larger than 140, 118, 48, and 32 kDa in DH 7. 5. An increase in net negative charge (- 30 Mv for DH 7.5) and a slight shift in the net neutrality (from pH 4.9 to 4.3) of the hydrolysates were observed which consequently impacted the electrostatic interaction with gum arabic. There was exposure of the hydrophobic amino acids up to 4-fold in comparison with the isolate and a red shift in maximum fluorescence wavelength in DH dependent manner following the hydrolysis. The denaturation temperature of the soluble complex from the hydrolysates shifted to higher values, having DH 5 with the maximum temperature (94.24 °C). A highly interconnected gel-like soluble complex network was formed having DH 5 with a better structure relative to DH 2 and 7.5. The study showed the use of limited tryptic hydrolysis at DH 5 as an effective approach to modify Bambara protein and provided a more stable and wider pH range of formation for soluble complex, thereby enhancing the food application.Keywords: Bambara groundnut, gum arabic, interaction, soluble complex
Procedia PDF Downloads 257102 A Study on the Korean Connected Industrial Parks Smart Logistics It Financial Enterprise Architecture
Authors: Ilgoun Kim, Jongpil Jeong
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Recently, a connected industrial parks (CIPs) architecture using new technologies such as RFID, cloud computing, CPS, Big Data, 5G 5G, IIOT, VR-AR, and ventral AI algorithms based on IoT has been proposed. This researcher noted the vehicle junction problem (VJP) as a more specific detail of the CIPs architectural models. The VJP noted by this researcher includes 'efficient AI physical connection challenges for vehicles' through ventilation, 'financial and financial issues with complex vehicle physical connections,' and 'welfare and working conditions of the performing personnel involved in complex vehicle physical connections.' In this paper, we propose a public solution architecture for the 'electronic financial problem of complex vehicle physical connections' as a detailed task during the vehicle junction problem (VJP). The researcher sought solutions to businesses, consumers, and Korean social problems through technological advancement. We studied how the beneficiaries of technological development can benefit from technological development with many consumers in Korean society and many small and small Korean company managers, not some specific companies. In order to more specifically implement the connected industrial parks (CIPs) architecture using the new technology, we noted the vehicle junction problem (VJP) within the smart factory industrial complex and noted the process of achieving the vehicle junction problem performance among several electronic processes. This researcher proposes a more detailed, integrated public finance enterprise architecture among the overall CIPs architectures. The main details of the public integrated financial enterprise architecture were largely organized into four main categories: 'business', 'data', 'technique', and 'finance'.Keywords: enterprise architecture, IT Finance, smart logistics, CIPs
Procedia PDF Downloads 1567101 The Effects of Gas Metal Arc Welding Parameters on the Corrosion Behaviour of Austenitic Stainless Steel Immersed in Aqueous Sodium Hydroxide
Authors: I. M. B. Omiogbemi, D. S. Yawas, I. M. Dagwa, F. G. Okibe
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This work present the effects of some gas metal arc welding parameters on the corrosion behavior of austenitic stainless steel, exposed to 0.5M sodium hydroxide at ambient temperatures (298K) using conventional weight loss determination, together with surface morphology evaluation by scanning electron microscopy and the application of factorial design of experiment to determine welding conditions which enhance the integrity of the welded stainless steel. The welding variables evaluated include speed, voltage and current. Different samples of the welded stainless steels were immersed in the corrosion environment for 8, 16, 24, 32 and 40 days and weight loss determined. From the results, it was found that increase in welding current and speed at constant voltage gave the optimum performance of the austenitic stainless steel in the environment. At a of speed 40cm/min, 110Amp current and voltage of 230 volt the welded stainless steel showed only a 0.0015mg loss in weight after 40 days. Pit-like openings were observed on the surface of the metals indicating corrosion but were minimal at the optimum conditions. It was concluded from the research that relatively high welding speed and current at a constant voltage gives a good welded austenitic stainless steel with better integrity.Keywords: welding, current, speed, austenitic stainless steel, sodium hydroxide
Procedia PDF Downloads 3087100 Investigation on the Structure of Temperature-Responsive N-isopropylacrylamide Microgels Containing a New Hydrophobic Crosslinker
Authors: G. Roshan Deen, J. S. Pedersen
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Temperature-responsive poly(N-isopropyl acrylamide) PNIPAM microgels crosslinked with a new hydrophobic chemical crosslinker was prepared by surfactant-mediated precipitation emulsion polymerization. The temperature-responsive property of the microgel and the influence of the crosslinker on the swelling behaviour was studied systematically by light scattering and small-angle X-ray scattering (SAXS). The radius of gyration (Rg) and the hydrodynamic radius (Rh) of the microgels decreased with increase in temperature due to the volume phase transition from a swollen to a collapsed state. The ratio of Rg/Rh below the transition temperature was lower than that of hard-spheres due to the lower crosslinking density of the microgels. The SAXS data was analysed by a model in which the microgels were modelled as core-shell particles with a graded interface. The model at intermediate temperatures included a central core and a more diffuse outer layer describing pending polymer chains with a low crosslinking density. In the fully swollen state, the microgels were modelled with a single component with a broad graded surface. In the collapsed state they were modelled as homogeneous and relatively compact particles. The polymer volume fraction inside the microgel was also derived based on the model and was found to increase with increase in temperature as a result of collapse of the microgel to compact particles. The polymer volume fraction in the core of the microgel in the collapsed state was about 60% which is higher than that of similar microgels crosslinked with hydrophilic and flexible cross-linkers.Keywords: microgels, SAXS, hydrophobic crosslinker, light scattering
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