Search results for: press cake
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 356

Search results for: press cake

146 Preparation and Fabrication of Lithium Disilicate Glass Ceramic as Dental Crowns via Hot Pressing Method

Authors: A. Srion, W. Thepsuwan, N. Monmaturapoj

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Two Lithium disilicate (LD) glass ceramics based on SiO2-Li2O-K2O-Al2O3 system were prepared through glass melting method and then fabricated into dental crowns via hot pressing at 850˚C and 900˚C in order to study the effect of the pressing temperatures on theirs phase formation and microstructure. The factor such as heat treatment temperature (as-cast glass, 600˚C and 700˚C) of the glass ceramics used to press was also investigated the effect of an initial microstructure before pressing. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to determine phase formation and microstructure of the samples, respectively. X-ray diffraction result shows that the main crystalline structure was Li2Si2O5 by having Li3PO4, Li0.6Al0.6Si2O6, Li2SiO3, Ca5 (PO4)3F, SiO2 as minor phases. Glass compositions with different heat treatment temperatures exhibited a difference phase formation but have less effect during pressing. Scanning electron microscopy analysis showed microstructure of lath-like of Li2Si2O5 in all glasses. With increasing the initial heat treatment temperature, the longer the lath-like crystals of lithium disilicate were increased especially when using glass heat treatment at 700˚C followed by pressing at 900˚C. This could be suggested that LD1 heat treatment at 700˚C which pressing at 900˚C presented the best formation by hot pressing and compiled microstructure.

Keywords: lithium disilicate, hot pressing, dental crown, microstructure

Procedia PDF Downloads 331
145 The Art of Looking (Back): The Female Gaze in Portrait de la Jeune Fille en Feu and Little Women

Authors: Louisa Browne Kirk

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In recent press interviews to promote Portrait de la jeune fille en feu (2019, translated to Portrait of a Lady on Fire in English), director and screenwriter Céline Sciamma and actors Adèle Haenel and Noémie Merlant repeatedly state that they understand the film as (if not uniquely, then unusually) produced via and supportive of ‘the female gaze’. Such a way of seeing stands in opposition to ‘the male gaze’, first theorised by Laura Mulvey as the way in which the female figure is a bearer, not maker, of meaning, a silent signifier through and against whom the male creator/viewer produces his fantasies and obsessions. What, then, is the female gaze? How does a woman produce meaning in and through film? Portrait de la jeune fille en feu and another very recent film, Little Women (2019, directed by Greta Gerwig), are unlikely companion films that understand the female gaze to be the act of one woman looking at another woman, a looking that is mediated through the production of art. In Sciamma’s film this looking is sexual and mediated through painting and in Gerwig’s film looking is familial and mediated through writing. In the schema of these films, art, love, looking and meaning are produced through collaboration. The painted and the painter, the written and the writer, are no longer rendered as subject and object but as dual creators, both always seeing and seen. The gaze of the cinematic woman, mediated through shared artistic practice, is ‘the desire-that-gives’.

Keywords: female gaze, Gerwig, Sciamma, shared artistic practice

Procedia PDF Downloads 185
144 Critical Analysis of Media Discourse and the Politics of Self-Censorship in Afghanistan

Authors: Abdul Wahab Rahimi

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This research examines the role of discursive strategies in the politics of self-censorship in Afghanistan, where political pressure, press freedom, and independent media work together, and language plays a vital role in implementing these strategies. Critical Discourse Analysis was conducted to describe the connection between language usage and the exercise of power by analyzing news stories related to women’s rights. This research focuses on 11 months of chronologically collected data from two mainstream television channels in Afghanistan: Tolo News and Ariana News. The findings show that Tolo News sustains and justifies juxtaposition and political critics’ discursive strategies to address women’s rights issues, criticize government policies, and deal with political pressure. At the same time, Ariana News follows the factual narrative strategy, practices self-censorship, and skips or partially focuses on the objective reporting of sensitive issues. The research concludes that the domestic media in Afghanistan follows the media policy of the Islamic Emirate of Afghanistan by covering sensitive issues and marginalizing women's rights issues in the media discourse.

Keywords: discursive strategies, Taliban, TV Channel, news stories, self-censorship, women's rights.

Procedia PDF Downloads 18
143 Surface Coatings of Boards Made from Alternative Materials

Authors: Stepan Hysek, Petra Gajdacova

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In recent years, alternative materials, such as annual plants or recycled and waste materials are becoming more and more popular input material for the production of composite materials. They can be used for the production of insulation boards, construction boards or furniture boards. Surface finishing of those boards is essential for utilization in furniture. However, some difficulties could occur during coating of boards from alternative materials; physical and chemical differences from conventional particleboards need to be considered. From the physical aspects, surface soundness and surface roughness mainly determine the quality of the surface. Since surface layers of boards from alternative materials have often lower density, these characteristics could be deteriorated and thus the production process needs to be optimized. Also, chemical reactions of board’s material with coating could be undesirable. The objective of this study is to evaluate the parameters affecting the surface quality of boards made form alternative materials and to find possibilities of the coating of these boards. In this study, boards of particles from rapeseed stems were produced using a laboratory press. Surface soundness, as representatives of mechanical properties and surface roughness, as representative of physical properties, were measured on boards from rapeseed stems. Results clearly indicated that produced boards had lower surface quality than commercially produced particle boards from wood. Therefore, higher thickness of surface coating on rapeseed based boards is needed.

Keywords: coating, surface, annual plant, composites, particleboard

Procedia PDF Downloads 277
142 Mechanical Characterization and Metallography of Sintered Aluminium-Titanium Diboride Metal Matrix Composite

Authors: Sai Harshini Irigineni, Suresh Kumar Reddy Narala

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The industrial applicability of aluminium metal matrix composites (AMMCs) has been rapidly growing due to their exceptional materials traits such as low weight, high strength, excellent thermal performance, and corrosion resistance. The increasing demand for AMMCs in automobile, aviation, aerospace and defence ventures has opened up windows of opportunity for the development of processing methods that facilitate low-cost production of AMMCs with superior properties. In the present work, owing to its economy, efficiency, and suitability, powder metallurgy (P/M) technique was employed to develop AMMCs with pure aluminium as matrix material and titanium diboride (TiB₂) as reinforcement. AMMC samples with different weight compositions (Al-0.1%TiB₂, Al-5%TiB₂, Al-10%TiB₂, and Al-15% TiB₂) were prepared through hot press compacting followed by traditional sintering. The developed AMMC was subjected to metallographic studies and mechanical characterization. Experimental evidences show significant improvement in mechanical properties such as tensile strength, hardness with increasing reinforcement content. The current study demonstrates the superiority of AMMCs over conventional metals and alloys and the results obtained may be of immense in material selection for different structural applications.

Keywords: AMMCs, mechanical characterization, powder metallurgy, TiB₂

Procedia PDF Downloads 135
141 Nanomaterials-Assisted Drilling Fluids for Application in Oil Fields - Challenges and Prospects

Authors: Husam Mohammed Saleh Alziyadi

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The drilling fluid has a significant impact on drilling efficiency. Drilling fluids have several functions which make them most important within the drilling process, such as lubricating and cooling the drill bit, removing cuttings from down of hole, preventing formation damage, suspending drill bit cuttings, , and also removing permeable formation as a result, the flow of fluid into the formation process is delayed. In the oil and gas sector, unconventional shale reserves have been a central player in meeting world energy demands. Oil-based drilling fluids (OBM) are generally favored for drilling shale plays due to negligible chemical interactions. Nevertheless, the industry has been inspired by strict environmental regulations to design water-based drilling fluids (WBM) capable of regulating shale-water interactions to boost their efficiency. However, traditional additives are too large to plug the micro-fractures and nanopores of the shale. Recently, nanotechnology in the oil and gas industries has shown a lot of promise, especially with drilling fluids based on nanoparticles. Nanotechnology has already made a huge contribution to technical developments in the energy sector. In the drilling industry, nanotechnology can make revolutionary changes. Nanotechnology creates nanomaterials with many attractive properties that can play an important role in improving the consistency of mud cake, reducing friction, preventing differential pipe sticking, preserving the stability of the borehole, protecting reservoirs, and improving the recovery of oil and gas. The selection of suitable nanomaterials should be based on the shale formation characteristics intended for drilling. The size, concentration, and stability of the NPs are three more important considerations. The effects of the environment are highly sensitive to these materials, such as changes in ionic strength, temperature, or pH, all of which occur under downhole conditions. This review paper focused on the previous research and recent development of environmentally friendly drilling fluids according to the regulatory environment and cost challenges.

Keywords: nanotechnology, WBM, Drilling Fluid, nanofluids

Procedia PDF Downloads 129
140 The Role of Media Relations in the Brand Image: Case Study in Three Brands of the Automobile Industry

Authors: Rosa Sobreira, Paula Arriscado

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Marketers are aware that media relations is an important touch point, which is also cheaper, to bring their products and their brands to the consumer. They recognize the role of journalists as moderators and transformers of public opinion, and they realize their influence on brand image. And also, they know that readers, listeners, viewers and internet users "believe" more what they read, hear and see in the news than in an advertisement. The study is focused on the automotive industry and analyses the news published about three brands that share industrial facilities and components. We wanted to understand the role of the information created by the brand`s media team in the journalists’ work, and the impact on management, activation and differentiation of brands and their products` attributes and benefits. Based on a qualitative methodology, the analysis focused on press news, making comparison between media coverage and their “narratives” about the three cars from different brands. The results point to the fact that journalists easily integrate speech from the marks on their products. In the case of this study, we found that apart from the description of the many similarities between the three cars, the average speech also "struggled" for revealing the attributes that differentiate them. This interpretation of the results helps us to understand the "marriage" between branding and media. We believe also this paper let us to understand how journalists, through news, join the speech of the brands.

Keywords: brand management, media relations, differentiation, positioning

Procedia PDF Downloads 226
139 Contesting Blind Obedience in Islam within the Malay-Language Media: Case Study of 'I Want to Touch a Dog' Event

Authors: Aisya Zaharin

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The reporting of Islam in the Malaysian government-controlled press is complicated and occurs almost daily. This is due to the Islamisation process that has been heavily politicized in recent years. This article analyses media representations of Islam in the Malaysian media through the social responsibility theory. A provocative case study of media reporting on the “I want to touch a dog” event was analysed since dog’s saliva is ritually considered unhygienic by Muslims. This paper will not question the Islamic ruling on the dog’s issue. Instead, it calls for discussions in relation to openness and maturity in religious discourse with respect to the dog’s saliva dialogue in 1937. It applies Hage’s “minor and major reality” to explain the increasing percentage of Muslim who define their own understandings of Islam vs the government’s dogmatic versions. This paper employs Alatas’s method of “sociological investigation in Southeast Asia” by using ethnographic examination on selected mass media. Through Asiacentricity approach, this paper revisited the local framework of Alatas’s New Man encouraging Muslims to engage in knowledge and to appreciate diversities in Islamic jurisprudences. Despite government’s control, findings showed that non-Malay languages and online media are more comprehensive in reporting the news about Islam. Clearly, there has to be a re-conceptualization of Islamic discourses in the Malay-language media.

Keywords: dog, Fiqh, Islamic jurisprudence, Malaysian media, New Man, social responsibility

Procedia PDF Downloads 322
138 Rethinking Peace Journalism in Pakistan: A Critical Analysis of News Discourse on the Afghan Refugee Repatriation Conflict

Authors: Ayesha Hasan

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This study offers unique perspectives and analyses of peace and conflict journalism through interpretative repertoire, media frames, and critical discourse analyses. Two major English publications in Pakistan, representing both long and short-form journalism, are investigated to uncover how the Afghan refugee repatriation from Pakistan in 2016-17 has been framed in Pakistani English media. Peace journalism focuses on concepts such as peace initiatives and peace building, finding common ground, and preventing further conflict. This study applies Jake Lynch’s Coding Criteria to guide the critical discourse analysis and Lee and Maslog’s Peace Journalism Quotient to examine the extent of peace journalism in each text. This study finds that peace journalism is missing in Pakistani English press, but represented, to an extent, in long-form print and online coverage. Two new alternative frames are also proposed. This study gives an in-depth understanding of if and how journalists in Pakistan are covering conflicts and framing stories that can be identified as peace journalism. This study represents significant contributions to the remarkably limited scholarship on peace and conflict journalism in Pakistan and extends Shabbir Hussain’s work on critical pragmatic perspectives on peace journalism in Pakistan.

Keywords: Afghan refugee repatriation, Critical discourse analysis, Media framing , Peace and conflict journalism

Procedia PDF Downloads 205
137 Quantitative Structure–Activity Relationship Analysis of Some Benzimidazole Derivatives by Linear Multivariate Method

Authors: Strahinja Z. Kovačević, Lidija R. Jevrić, Sanja O. Podunavac Kuzmanović

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The relationship between antibacterial activity of eighteen different substituted benzimidazole derivatives and their molecular characteristics was studied using chemometric QSAR (Quantitative Structure–Activity Relationships) approach. QSAR analysis has been carried out on inhibitory activity towards Staphylococcus aureus, by using molecular descriptors, as well as minimal inhibitory activity (MIC). Molecular descriptors were calculated from the optimized structures. Principal component analysis (PCA) followed by hierarchical cluster analysis (HCA) and multiple linear regression (MLR) was performed in order to select molecular descriptors that best describe the antibacterial behavior of the compounds investigated, and to determine the similarities between molecules. The HCA grouped the molecules in separated clusters which have the similar inhibitory activity. PCA showed very similar classification of molecules as the HCA, and displayed which descriptors contribute to that classification. MLR equations, that represent MIC as a function of the in silico molecular descriptors were established. The statistical significance of the estimated models was confirmed by standard statistical measures and cross-validation parameters (SD = 0.0816, F = 46.27, R = 0.9791, R2CV = 0.8266, R2adj = 0.9379, PRESS = 0.1116). These parameters indicate the possibility of application of the established chemometric models in prediction of the antibacterial behaviour of studied derivatives and structurally very similar compounds.

Keywords: antibacterial, benzimidazole, molecular descriptors, QSAR

Procedia PDF Downloads 367
136 Four Decades of Greek Artistic Presence in Paris (1970-2010): Theory and Interpretation

Authors: Sapfo A. Mortaki

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This article examines the presence of Greek immigrant artists (painters and sculptors) in Paris during 1970-2010. The aim is to highlight their presence in the French capital through archival research in the daily and periodical press as well as present the impact of their artistic activity on the French intellectual life and society. At the same time, their contribution to the development of cultural life in Greece becomes apparent. The integration of those migrant artists into an environment of cultural coexistence and the understanding of the social phenomenon of their migration, in the context of postmodernity, are being investigated. The cultural relations between the two countries are studied in the context of support mechanisms, such as the Greek community, cultural institutions, museums and galleries. The recognition of the Greek artists by the French society and the social dimension in the context of their activity in Paris, are discussed in terms of the assimilation theory. Since the 1970s, and especially since the fall of the dictatorship in Greece, in opposition to the prior situation, artists' contacts with their homeland have been significantly enhanced, with most of them now travelling to Paris, while others work in parallel in both countries. As a result, not only do the stages of the development of their work through their pursuits become visible, but, most importantly, the artistic world becomes informed about the multifaceted expression of art through the succession of various contemporary currents. Thus, the participation of Greek artists in the international cultural landscape is demonstrated.

Keywords: artistic migration, cultural impact, Greek artists, postmodernity, theory of assimilation

Procedia PDF Downloads 309
135 Magnetodielectric Studies of Substituted La₂NiMnO₆ Double Perovskites

Authors: Pravin M. Tirmali, Sagar M. Mane, Snehal L. Kadam, Shriniwas B. Kulkarni

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The La₂NiMnO₆ has been extensively studied for its ferromagnetic and magneto-dielectric properties. The La₂NiMnO₆ double perovskite is modified by partial substitution at B site by Fe transition metal. The La₂Ni₁₋ₓFeₓMnO₆ powder samples were synthesized by hydroxide co-precipitation method. The precipitate was dried and fine griended to form powder and pellet samples (2cm dia.) using hydraulic press. The powder and pellet samples of La₂Ni₁₋ₓFeₓMnO₆ were calcined at high temperature 1200°C to form a pure and stable composition. The nano polar regions (NPR) around Ni²⁺ or Mn⁴⁺ ions due to the cationic antisite disorder gives dielectric relaxation through their mutual interaction. The magneto-dielectric behavior is observed in substituted La₂NiMnO₆ shows Maxwell-Wagner and Debye relaxation due to grain boundary, interface and antisite defects. The magneto-dielectric properties of substituted La₂NiMnO₆ pellet sample were probed by Impedance spectroscopy measurements. The structural and magnetic investigations were also carried out by XRD, FESEM and VSM measurements of substituted La₂NiMnO₆ of powder samples. The synthesized La₂Ni₁₋ₓFeₓMnO₆ powder samples are polycrystalline and ferromagnetic in nature. The La₂Ni₁₋ₓFeₓMnO₆ samples exhibit ferromagnetic disorder with transition temperature near room temperature.

Keywords: La₂NiMnO₆, nano polar regions (NPR), antisite defects, magnetodielctric

Procedia PDF Downloads 218
134 Effects of Initial Moisture Content on the Physical and Mechanical Properties of Norway Spruce Briquettes

Authors: Miloš Matúš, Peter Križan, Ľubomír Šooš, Juraj Beniak

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The moisture content of densified biomass is a limiting parameter influencing the quality of this solid biofuel. It influences its calorific value, density, mechanical strength and dimensional stability as well as affecting its production process. This paper deals with experimental research into the effect of moisture content of the densified material on the final quality of biofuel in the form of logs (briquettes or pellets). Experiments based on the single-axis densification of the spruce sawdust were carried out with a hydraulic piston press (piston and die), where the densified logs were produced at room temperature. The effect of moisture content on the qualitative properties of the logs, including density, change of moisture, expansion and physical changes, and compressive and impact resistance were studied. The results show the moisture ranges required for producing good-quality logs. The experiments were evaluated and the moisture content of the tested material was optimized to achieve the optimum value for the best quality of the solid biofuel. The dense logs also have high-energy content per unit volume. The research results could be used to develop and optimize industrial technologies and machinery for biomass densification to achieve high quality solid biofuel.

Keywords: biomass, briquettes, densification, fuel quality, moisture content, density

Procedia PDF Downloads 430
133 Characterization of Carbon/Polyamide 6,6 (C/PA66) Composite Material for Dry and Wet Conditions

Authors: Tariq Bashir, Muhammad Waseem Tahir, Ulf Stigh, Behnaz Baghaie, Mikael Skrifvars

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Absorption of moisture may cause many problems in a composite material, such as delamination, degradation of the strength and increase in the weight. For small coupons, the increase in weight may be negligible, however, for large structures increase in weight due to moisture absorption may be quite significant. Polyamides (PA6, PA66) absorb more moisture as compared to other thermoplastics. There are many parameters which affect the moisture absorption of the composite material for example temperature, pressure, type of matrix and fibers, thickness of the material and relative humidity (RH) etc. So, it is utmost important to investigate the impact of moisture on PA66 based composites which can be done by characterizing the mechanical properties of composite materials both for dry and wet conditions. In this study, laminates of C/PA66 composite are manufactured by first heating the commingled material in conventional oven at a temperature of 220 °C followed by pressing in a manual hot press for 20 minutes with preheated platen at 220 °C. To observe the moisture absorption of the composite, coupons of the material were placed in a climate chamber at five different conditions 0, 25, 50, 75 and 100% RH for 24 hours. Five specimens were used for each condition. These coupons were weighed before placing in the climate chamber and just after removing from the chamber to observe the moisture absorption of the material. The mechanical characterization such as tensile strength, flexural modulus, impact strength and DMTA of C/PA66 material are performed at 0, 50 and 100 % RH. The work is going on for the testing of the material and results will be presented in full paper.

Keywords: Carbon/Polyamide 66 composites, structural composites, mechanical characterizations, wet and dry conditions

Procedia PDF Downloads 237
132 Upsetting of Tri-Metallic St-Cu-Al and St-Cu60Zn-Al Cylindrical Billets

Authors: Isik Cetintav, Cenk Misirli, Yilmaz Can

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This work investigates upsetting of the tri-metallic cylindrical billets both experimentally and analytically with a reduction ratio 30%. Steel, brass, and copper are used for the outer and outmost rings and aluminum for the inner core. Two different models have been designed to show material flow and the cavity took place over the two interfaces during forming after this reduction ratio. Each model has an outmost ring material as steel. Model 1 has an outer ring between the outmost ring and the solid core material as copper and Model 2 has a material as brass. Solid core is aluminum for each model. Billets were upset in press machine by using parallel flat dies. Upsetting load was recorded and compared for models and single billets. To extend the tests and compare with experimental procedure to a wider range of inner core and outer ring geometries, finite element model was performed. ABAQUS software was used for the simulations. The aim is to show how contact between outmost ring, outer ring and the inner core are carried on throughout the upsetting process. Results have shown that, with changing in height, between outmost ring, outer ring and inner core, the Model 1 and Model 2 had very good interaction, and the contact surfaces of models had various interface behaviour. It is also observed that tri-metallic materials have lower weight but better mechanical properties than single materials. This can give an idea for using and producing these new materials for different purposes.

Keywords: tri-metallic, upsetting, copper, brass, steel, aluminum

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131 Comparison Between Vegans and Omnivores on the Recovery of Delayed Onset Muscle Soreness in Young Females

Authors: Njeim Pressila, Hajj-Boutros Guy, Antony D. Karelis

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Background: Acute resistance exercise is associated with an elevated inflammation response, which could lead to delayed onset muscle soreness (DOMS). There is evidence that suggests that ingesting foods that have anti-inflammation properties may help reduce DOMS. A vegan diet has also been shown to be an anti-inflammatory diet which could, in turn, decrease DOMS. Objective and hypothesis: The purpose of the present study will be to compare markers of DOMS between vegans and omnivores after acute resistance exercise in young females. We hypothesize that vegans will have a better recovery of DOMS markers after a resistance exercise session compared to omnivores. Methods: Population: We will recruit30 vegans and 30 omnivores to participate in this study. Allvolunteers will follow either a vegan or an omnivore diet for at least 2 years. Anthropometric measurements, body composition, musclestrength (leg and chest press), markers of DOMS (swelling, pain, and stiffness), and dietary factors, as well as a wellness and anxiety questionnaire will be measured. All participants will also perform an acute resistance exercise session in order to induce DOMS. Pertinence: This project will give us a better understanding on the recovery process of vegans after a resistance training session and, as such, provide useful information to health professionals and athletes/coaches (kinesiologists and nutritionists)

Keywords: vgeans, omnivores, delayed onset muscle soreness, pain, stifness

Procedia PDF Downloads 128
130 Technico-Economical Study of a Rapeseed Based Biorefinery Using High Voltage Electrical Discharges and Ultrasounds as Pretreatment Technologies

Authors: Marwa Brahim, Nicolas Brosse, Nadia Boussetta, Nabil Grimi, Eugene Vorobiev

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Rapeseed plant is an established product in France which is mainly dedicated to oil production. However, the economic potential of residues from this industry (rapeseed hulls, rapeseed cake, rapeseed straw etc.), has not been fully exploited. Currently, only low-grade applications are found in the market. As a consequence, it was deemed of interest to develop a technological platform aiming to convert rapeseed residues into value- added products. Specifically, a focus is given on the conversion of rapeseed straw into valuable molecules (e.g. lignin, glucose). Existing pretreatment technologies have many drawbacks mainly the production of sugar degradation products that limit the effectiveness of saccharification and fermentation steps in the overall scheme of the lignocellulosic biorefinery. In addition, the viability of fractionation strategies is a challenge in an environmental context increasingly standardized. Hence, the need to find cleaner alternatives with comparable efficiency by implementing physical phenomena that could destabilize the structural integrity of biomass without necessarily using chemical solvents. To meet environmental standards increasingly stringent, the present work aims to study the new pretreatment strategies involving lower consumption of chemicals with an attenuation of the severity of the treatment. These strategies consist on coupling physical treatments either high voltage electrical discharges or ultrasounds to conventional chemical pretreatments (soda and organosolv). Ultrasounds treatment is based on the cavitation phenomenon, and high voltage electrical discharges cause an electrical breakdown accompanied by many secondary phenomena. The choice of process was based on a technological feasibility study taking into account the economic profitability of the whole chain after products valorization. Priority was given to sugars valorization into bioethanol and lignin sale.

Keywords: high voltage electrical discharges, organosolv, pretreatment strategies, rapeseed straw, soda, ultrasounds

Procedia PDF Downloads 365
129 Liposome Sterile Filtration Fouling: The Impact of Transmembrane Pressure on Performance

Authors: Hercules Argyropoulos, Thomas F. Johnson, Nigel B Jackson, Kalliopi Zourna, Daniel G. Bracewell

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Lipid encapsulation has become essential in drug delivery, notably for mRNA vaccines during the COVID-19 pandemic. However, their sterile filtration poses challenges due to the risk of deformation, filter fouling and product loss from adsorption onto the membrane. Choosing the right filtration membrane is crucial to maintain sterility and integrity while minimizing product loss. The objective of this study is to develop a rigorous analytical framework utilizing confocal microscopy and filtration blocking models to elucidate the fouling mechanisms of liposomes as a model system for this class of delivery vehicle during sterile filtration, particularly in response to variations in transmembrane pressure (TMP) during the filtration process. Experiments were conducted using fluorescent Lipoid S100 PC liposomes formulated by micro fluidization and characterized by Multi-Angle Dynamic Light Scattering. Dual-layer PES/PES and PES/PVDF membranes with 0.2 μm pores were used for filtration under constant pressure, cycling from 30 psi to 5 psi and back to 30 psi, with 5, 6, and 5-minute intervals. Cross-sectional membrane samples were prepared by microtome slicing and analyzed with confocal microscopy. Liposome characterization revealed a particle size range of 100-140 nm and an average concentration of 2.93x10¹¹ particles/mL. Goodness-of-fit analysis of flux decline data at varying TMPs identified the intermediate blocking model as most accurate at 30 psi and the cake filtration model at 5 psi. Membrane resistance analysis showed atypical behavior compared to therapeutic proteins, with resistance remaining below 1.38×10¹¹ m⁻¹ at 30 psi, increasing over fourfold at 5 psi, and then decreasing to 1-1.3-fold when pressure was returned to 30 psi. This suggests that increased flow/shear deforms liposomes enabling them to more effectively navigate membrane pores. Confocal microscopy indicated that liposome fouling mainly occurred in the upper parts of the dual-layer membrane.

Keywords: sterile filtration, membrane resistance, microfluidization, confocal microscopy, liposomes, filtration blocking models

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128 Generation of Electro-Encephalography Readiness Potentials by Intention

Authors: Seokbeen Lim, Gilwon Yoon

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The readiness potential in brain waves is a brain activity related with an intention whose potential arises even before its conscious intention. This study was carried out in order to understand the generation and mechanism of the readiness potential more. The experiment with two subjects was conducted in two ways following the Oddball task protocol. Firstly, auditory stimuli were randomly presented to the subjects. The subject was allowed to press the keyboard with the right index finger only when the subject heard the target stimulus but not the standard stimulus. Secondly, unlike the first one, the auditory stimuli were randomly presented, and the subjects pressed the keyboard in the same manner, but at the same time with grasping action of the left hand. The readiness potential showed up for both of these experiments. In the first Oddball experiment, the readiness potential was detected only when the target stimulus was presented. However, in the second Oddball experiment with the left hand action of grasping something, the readiness potential was detected at the presentation of for both standard and target stimuli. However, detected readiness potentials with the target stimuli were larger than those of the standard stimuli. We found an interesting phenomenon that the readiness potential was able to be detected even the standard stimulus. This indicates that motor-related readiness potentials can be generated only by the intention to move. These results present a new perspective in psychology and brain engineering since subconscious brain action may be prior to conscious recognition of the intention.

Keywords: readiness potential, auditory stimuli, event-related potential, electroencephalography, oddball task

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127 The Old Basis of Press Authority and New Media: Devolution of Communication Power Base in Nigeria by X (Formally Twitter)

Authors: Nzeaka Emmanuel Ezimako

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With the advent of new media, especially X, the government's previous foundation of media power and control in Nigeria has been diminished because they can no longer regulate the public sphere to control social action and reactions. This study examined how IPOB (Indigenous People of Biafra) resistance and the 2020 #Endsars aborted revolution were able to control public discourse during social upheavals, as well as how the new media have diminished the influence that the government and media owners once had over Nigerians. This study is significant because it recognizes the social transformation brought about by the emergence of new media, particularly with the most widely used social media platform in Nigeria, X, and how citizen media activity is altering the media ecosystem and challenging the government and private media owners' hegemony over news coverage in Nigeria to the point where the government saw X as a blatant threat to its hegemony and banned it in 2021. This study used a triangulation of qualitative and quantitative analysis with 300 respondents (n=300) from different sectors of the media practitioners, scholars, and university students in Nigeria to draw a conclusion in line with Democratic Participant Media Theory, which questions the necessity for centralized media regulated by the government and conglomerates. The contributions to filling the gap in the literature are meant to aid readers in comprehending how X has developed into a dominant force in Nigerian media, particularly during the crisis. The study offers recommendations for media executives, policymakers, and the public on how to manage the media conflict that has developed because of the loss of official government oversight of the mass media due to the emergence of X in the media space.

Keywords: Twitter, new media, regulations, dominance, resistance

Procedia PDF Downloads 94
126 Eco-Friendly Softener Extracted from Ricinus communis (Castor) Seeds for Organic Cotton Fabric

Authors: Fisaha Asmelash

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The processing of textiles to achieve a desired handle is a crucial aspect of finishing technology. Softeners can enhance the properties of textiles, such as softness, smoothness, elasticity, hydrophilicity, antistatic properties, and soil release properties, depending on the chemical nature used. However, human skin is sensitive to rough textiles, making softeners increasingly important. Although synthetic softeners are available, they are often expensive and can cause allergic reactions on human skin. This paper aims to extract a natural softener from Ricinus communis and produce an eco-friendly and user-friendly alternative due to its 100% herbal and organic nature. Crushed Ricinus communis seeds were soaked in a mechanical oil extractor for one hour with a 100g cotton fabric sample. The defatted cake or residue obtained after the extraction of oil from the seeds, also known as Ricinus communis meal, was obtained by filtering the raffinate and then dried at 1030c for four hours before being stored under laboratory conditions for the softening process. The softener was applied directly to 100% cotton fabric using the padding process, and the fabric was tested for stiffness, crease recovery, and drape ability. The effect of different concentrations of finishing agents on fabric stiffness, crease recovery, and drape ability was also analyzed. The results showed that the change in fabric softness depends on the concentration of the finish used. As the concentration of the finish was increased, there was a decrease in bending length and drape coefficient. Fabrics with a high concentration of softener showed a maximum decrease in drape coefficient and stiffness, comparable to commercial softeners such as silicon. The highest decrease in drape coefficient was found to be comparable with commercial softeners, silicon. Maximum increases in crease recovery were seen in fabrics treated with Ricinus communis softener at a concentration of 30gpl. From the results, the extracted softener proved to be effective in the treatment of 100% cotton fabric

Keywords: ricinus communis, crease recovery, drapability, softeners, stiffness

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125 Software Vulnerability Markets: Discoverers and Buyers

Authors: Abdullah M. Algarni, Yashwant K. Malaiya

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Some of the key aspects of vulnerability-discovery, dissemination, and disclosure-have received some attention recently. However, the role of interaction among the vulnerability discoverers and vulnerability acquirers has not yet been adequately addressed. Our study suggests that a major percentage of discoverers, a majority in some cases, are unaffiliated with the software developers and thus are free to disseminate the vulnerabilities they discover in any way they like. As a result, multiple vulnerability markets have emerged. In some of these markets, the exchange is regulated, but in others, there is little or no regulation. In recent vulnerability discovery literature, the vulnerability discoverers have remained anonymous individuals. Although there has been an attempt to model the level of their efforts, information regarding their identities, modes of operation, and what they are doing with the discovered vulnerabilities has not been explored. Reports of buying and selling of the vulnerabilities are now appearing in the press; however, the existence of such markets requires validation, and the natures of the markets need to be analysed. To address this need, we have attempted to collect detailed information. We have identified the most prolific vulnerability discoverers throughout the past decade and examined their motivation and methods. A large percentage of these discoverers are located in Eastern and Western Europe and in the Far East. We have contacted several of them in order to collect first-hand information regarding their techniques, motivations, and involvement in the vulnerability markets. We examine why many of the discoverers appear to retire after a highly successful vulnerability-finding career. The paper identifies the actual vulnerability markets, rather than the hypothetical ideal markets that are often examined. The emergence of worldwide government agencies as vulnerability buyers has significant implications. We discuss potential factors that can impact the risk to society and the need for detailed exploration.

Keywords: risk management, software security, vulnerability discoverers, vulnerability markets

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124 The Discursive Construction of Emotions in the Headlines of French Newspapers on Seismic Disasters

Authors: Mirela-Gabriela Bratu

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The main objective of this study is to highlight the way in which emotions are constructed discursively in the French written press, more particularly in the titles of informative articles. To achieve this objective, we will begin the study with the theoretical part, which aims to capture the characteristics of journalistic discourse, to which we will add clues of emotions that we will identify in the titles of the articles. The approach is based on the empirical results from the analysis of the articles published on the earthquake that took place on August 24, 2016, in Italy, as described by two French national daily newspapers: Le Monde and Le Point. The corpus submitted to the analysis contains thirty-seven titles, published between August 24, 2016, and August 24, 2017. If the textual content of the speech offers information respecting the grammatical standards and following the presentation conventions, the choice of words can touch the reader, so the journalist must add other means than mastering of the language to create emotion. This study aims to highlight the strategies, such as rhetorical figures, the tenses, or factual data, used by journalists to create emotions for the readers. We also try, thanks to the study of the articles which were published for several days relating to the same event, to emphasize whether we can speak or not of the dissipation of emotion and the catastrophic side as the event fades away in time. The theoretical framework is offered by works on rhetorical strategies (Perelman, 1992; Amossi, 2000; Charaudeau, 2000) and on the study of emotions (Plantin, 1997, 1998, 2004; Tetu, 2004).

Keywords: disaster, earthquake, emotion, feeling

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123 Modification of Date Palm Leaflets Fibers Used as Thermoplastic Reinforcement

Authors: K. Almi, S.Lakel, A. Benchabane, A. Kriker

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The fiber–matrix compatibility can be improved if suitable enforcements are chosen. Whenever the reinforcements have more thermal stability, they can resist to the main processes for wood–thermoplastic composites. This paper is an investigation of effect of different treatment process on the mechanical proprieties and on the thermal stability of date palm leaflets fibers with a view to improve the date palm fiber proprieties used as reinforcement of thermoplastic materials which main processes require extrusion, hot press. To compare the effect of alkali and acid treatment on the date palm leaflets fiber properties, different treatment were used such as Sodium hydroxide NaOH solution, aluminium chloride AlCl3 and acid treatment with HCL solution. All treatments were performed at 70°C for 4h and 48 h. The mechanical performance (tensile strength and elongation) is affected by immersion time in alkaline and acid solutions. The reduction of the tensile strength and elongation of fibers at 48h was higher in acid treatment than in alkali treatment at high concentration. No significant differences were observed in mechanical and thermal proprieties of raw fibers and fibers submerged in AlCl3 at low concentration 1% for 48h. Fibers treated by NaOH at 6% for 4h showed significant increase in the mechanical proprieties and thermal stability of date palm leaflets fibers. Hence, soda treatment is necessary to improve the fibers proprieties and consequently optimize the composite performance.

Keywords: date palm fibers, surface treatments, thermoplastic composites, thermal analysis

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122 Treatment of Municipal Wastewater by Means of Uv-Assisted Irradiation Technologies: Fouling Studies and Optimization of Operational Parameters

Authors: Tooba Aslam, Efthalia Chatzisymeon

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UV-assisted irradiation technologies are well-established for water and wastewater treatment. UVC treatments are widely used at large-scale, while UVA irradiation has more often been applied in combination with a catalyst (e.g. TiO₂ or FeSO₄) in smaller-scale systems. A technical issue of these systems is the formation of fouling on the quartz sleeves that houses the lamps. This fouling can prevent complete irradiation, therefore reducing the efficiency of the process. This paper investigates the effects of operational parameters, such as the type of wastewater, irradiation source, H₂O₂ addition, and water pH on fouling formation and, ultimately, the treatment of municipal wastewater. Batch experiments have been performed at lab-scale while monitoring water quality parameters including: COD, TS, TSS, TDS, temperature, pH, hardness, alkalinity, turbidity, TOC, UV transmission, UV₂₅₄ absorbance, and metal concentrations. The residence time of the wastewater in the reactor was 5 days in order to observe any fouling formation on the quartz surface. Over this period, it was observed that chemical oxygen demand (COD) decreased by 30% and 59% during photolysis (Ultraviolet A) and photo-catalysis (UVA/Fe/H₂O₂), respectively. Higher fouling formation was observed with iron-rich and phosphorous-rich wastewater. The highest rate of fouling was developed with phosphorous-rich wastewater, followed by the iron-rich wastewater. Photo-catalysis (UVA/Fe/H₂O₂) had better removal efficiency than photolysis (UVA). This was attributed to the Photo-Fenton reaction, which was initiated under these operational conditions. Scanning electron microscope (SEM) measurements of fouling formed on the quartz sleeves showed that particles vary in size, shape, and structure; some have more distinct structures and are generally larger and have less compact structure than the others. Energy-dispersive X-ray spectroscopy (EDX) results showed that the major metals present in the fouling cake were iron, phosphorous, and calcium. In conclusion, iron-rich wastewaters are more suitable for UV-assisted treatment since fouling formation on quartz sleeves can be minimized by the formation of oxidizing agents during treatment, such as hydroxyl radicals.

Keywords: advanced oxidation processes, photo-fenton treatment, photo-catalysis, wastewater treatment

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121 Comparison of Polyphonic Profile of a Berry from Two Different Sources, Using an Optimized Extraction Method

Authors: G. Torabian, A. Fathi, P. Valtchev, F. Dehghani

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The superior polyphenol content of Sambucus nigra berries has high health potentials for the production of nutraceutical products. Numerous factors influence the polyphenol content of the final products including the berries’ source and the subsequent processing production steps. The aim of this study is to compare the polyphenol content of berries from two different sources and also to optimise the polyphenol extraction process from elderberries. Berries from source B obtained more acceptable physical properties than source A; a single berry from source B was double in size and weight (both wet and dry weight) compared with a source A berry. Despite the appropriate physical characteristics of source B berries, their polyphenolic profile was inferior; as source A berries had 2.3 fold higher total anthocyanin content, and nearly two times greater total phenolic content and total flavonoid content compared to source B. Moreover, the result of this study showed that almost 50 percent of the phenolic content of berries are entrapped within their skin and pulp that potentially cannot be extracted by press juicing. To address this challenge and to increase the total polyphenol yield of the extract, we used cold-shock blade grinding method to break the cell walls. The result of this study showed that using cultivars with higher phenolic content as well as using the whole fruit including juice, skin and pulp can increase polyphenol yield significantly; and thus, may boost the potential of using elderberries as therapeutic products.

Keywords: different sources, elderberry, grinding, juicing, polyphenols

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120 Heat Forging Analysis Method on Blank Consist of Two Metals

Authors: Takashi Ueda, Shinichi Enoki

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Forging parts is used to automobiles. Because they have high strength and it is possible to press them into complicated shape. When it is possible to manufacture hollow forging parts, it leads to reduce weight of the automobiles. But, hollow forging parts are confined to axisymmetrical shape. Hollow forging parts that were pressed to complicated shape are expected. Therefore, we forge a blank that aluminum alloy was inserted in stainless steel. After that, we can provide complex forging parts that are reduced weight, if it is possible to be melted the aluminum alloy away by using different of melting points. It is necessary to establish heat forging analysis method on blank consist of stainless steel and aluminum alloy. Because, this forging is different from conventional forging and this technology is not confirmed. In this study, we compared forging experiment with numerical analysis on the view point of forming load and shape after forming and establish how to set the material temperatures of two metals and material property of stainless steel on the analysis method. Consequently, temperature difference of stainless steel and aluminum alloy was obtained by experiment. We got material property of stainless steel on forging experimental by compression tests. We had compared numerical analysis that was used the temperature difference of two metals and the material property of stainless steel on forging experimental with forging experiment. Forging analysis method on blank consist of two metals was established by result of numerical analysis having agreed with result of forging experiment.

Keywords: forging, lightweight, analysis, hollow

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119 The Material Behavior in Curved Glulam Beam of Jabon Timber

Authors: Erma Desmaliana, Saptahari Sugiri

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Limited availability of solid timber in large dimensions becomes a problem. The demands of timbers in Indonesia is more increasing compared to its supply from natural forest. It is associated with the issues of global warming and environmental preservation. The uses of timbers from HTI (Industrial Planting Forest) and HTR (Society Planting Forest), such as Jabon, is an alternative source that required to solve these problems. Having shorter lifespan is the benefit of HTI/HTR timbers, although they are relatively smaller in dimension and lower in strength. Engineering Wood Product (EWP) such as glulam (glue-laminated) timber, is required to overcome their losses. Glulam is fabricated by gluing the wooden planks that having a thickness of 20 to 45 mm with an adhesive material and a certain pressure. Glulam can be made a curved beam, is one of the advantages, thus making it strength is greater than a straight beam. This paper is aimed to know the material behavior of curved glue-laminated beam of Jabon timber. Preliminary methods was to gain physical and mechanical properties, and glue spread strength of Jabon timber, which following the ASTM D-143 standard test method. Dimension of beams were 50 mm wide, 760 mm span, 50 mm thick, and 50 mm rise. Each layer of Jabon has a thickness of 5 mm and is glued with polyurethane. Cold press will be applied to beam laminated specimens for more than 5 hours. The curved glue-laminated beams specimens will be tested about the bending behavior. This experiments aims to obtain the increasing of load carrying capacity and stiffness of curved glulam beam.

Keywords: curved glulam beam, HTR&HTI, load carrying, strength

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118 General Evaluation of a Three-Year Holistic Physical Activity Interventions Program in Qatar Campuses: Step into Health (SIH) in Campuses 2013- 2016

Authors: Daniela Salih Khidir, Mohamed G. Al Kuwari, Mercia V. Walt, Izzeldin J. Ibrahim

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Background: University-based physical activity interventions aim to establish durable social patterns during the transition to adulthood. This study is a comprehensive evaluation of a 3-year intervention-based program to increase the culture of physical activity (PA) routine in Qatar campuses community, using a holistic approach. Methodology: General assessment methods: formative evaluation-SIH Campuses logic model design, stakeholders’ identification; process evaluation-members’ step counts analyze and qualitative Appreciative Inquiry session (4-D model); daily steps categorized as: ≤5,000, inactive; 5,000-7,499 low active; ≥7,500, physically active; outcome evaluation - records 3 years interventions. Holistic PA interventions methods: walking interventions - pedometers distributions and walking competitions for students and staff; educational interventions - in campuses implementation of bilingual educational materials, lectures, video related to PA in prevention of non-communicable diseases (NCD); articles published online; monthly emails and sms notifications for pedometer use; mass media campaign - radio advertising, yearly pre/post press releases; community stakeholders interventions-biyearly planning/reporting/achievements rewarding/ qualitative meetings; continuous follow-up communication, biweekly steps reports. Findings: Results formative evaluation - SIH in Campuses logic model identified the need of PA awareness and education within universities, resources, activities, health benefits, program continuity. Results process evaluation: walking interventions: Phase 1: 5 universities recruited, 2352 members, 3 months competition; Phase 2: 6 new universities recruited, 1328 members in addition, 4 months competition; Phase 3: 4 new universities recruited in addition, 1210 members, 6 months competition. Results phase 1 and 2: 1,299 members eligible for analyzes: 800 females (62%), 499 males (38%); 86% non-Qataris, 14% Qatari nationals, daily step count 5,681 steps, age groups 18–24 (n=841; 68%) students, 25–64; (n=458; 35.3%) staff; 38% - low active, 37% physically active and 25% inactive. The AI main themes engaging stakeholders: awareness/education - 5 points (100%); competition, multi levels of involvement in SIH, community-based program/motivation - 4 points each (80%). The AI points represent themes’ repetition within stakeholders’ discussions. Results education interventions: 2 videos implementation, 35 000 educational materials, 3 online articles, 11 walking benefits lectures, 40 emails and sms notifications. Results community stakeholders’ interventions: 6 stakeholders meetings, 3 rewarding gatherings, 1 focus meeting, 40 individual reports, 18 overall reports. Results mass media campaign: 1 radio campaign, 7 press releases, 52 campuses newsletters. Results outcome evaluation: overall 2013-2016, the study used: 1 logic model, 3 PA holistic interventions, partnerships 15 universities, registered 4890 students and staff (aged 18-64 years), engaged 30 campuses stakeholders and 14 internal stakeholders; Total registered population: 61.5% female (2999), 38.5% male (1891), 20.2% (988) Qatari nationals, 79.8% (3902) non-Qataris, 55.5% (2710) students aged 18 – 25 years, 44.5% (2180) staff aged 26 - 64 years. Overall campaign 1,558 members eligible for analyzes: daily step count 7,923; 37% - low active, 43% physically active and 20% inactive. Conclusion: The study outcomes confirm program effectiveness and engagement of young campuses community, specifically female, in PA. The authors recommend implementations of 'holistic PA intervention program approach in Qatar' aiming to impact the community at national level for PA guidelines achievement in support of NCD prevention.

Keywords: campuses, evaluation, Qatar, step-count

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117 Development of a PJWF Cleaning Method for Wet Electrostatic Precipitators

Authors: Hsueh-Hsing Lu, Thi-Cuc Le, Tung-Sheng Tsai, Chuen-Jinn Tsai

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This study designed and tested a novel wet electrostatic precipitators (WEP) system featuring a Pulse-Air-Jet-Assisted Water Flow (PJWF) to shorten water cleaning time, reduce water usage, and maintain high particle removal efficiency. The PJWF injected cleaning water tangentially at the cylinder wall, rapidly enhancing the momentum of the water flow for efficient dust cake removal. Each PJWF cycle uses approximately 4.8 liters of cleaning water in 18 seconds. Comprehensive laboratory tests were conducted using a single-tube WEP prototype within a flow rate range of 3.0 to 6.0 cubic meters per minute(CMM), operating voltages between -35 to -55 kV, and high-frequency power supply. The prototype, consisting of 72 sets of double-spike rigid discharge electrodes, demonstrated that with the PJWF, -35 kV, and 3.0 CMM, the PM2.5 collection efficiency remained as high as the initial value of 88.02±0.92% after loading with Al2O3 particles at 35.75± 2.54 mg/Nm3 for 20-hr continuous operation. In contrast, without the PJWF, the PM2.5 collection efficiency drastically dropped from 87.4% to 53.5%. Theoretical modeling closely matched experimental results, confirming the robustness of the system's design and its scalability for larger industrial applications. Future research will focus on optimizing the PJWF system, exploring its performance with various particulate matter, and ensuring long-term operational stability and reliability under diverse environmental conditions. Recently, this WEP was combined with a preceding CT (cooling tower) and a HWS (honeycomb wet scrubber) and pilot-tested (40 CMM) to remove SO2 and PM2.5 emissions in a sintering plant of an integrated steel making plant. Pilot-test results showed that the removal efficiencies for SO2 and PM2.5 emissions are as high as 99.7 and 99.3 %, respectively, with ultralow emitted concentrations of 0.3 ppm and 0.07 mg/m3, respectively, while the white smoke is also eliminated at the same time. These new technologies are being used in the industry and the application in different fields is expected to be expanded to reduce air pollutant emissions substantially for a better ambient air quality.

Keywords: wet electrostatic precipitator, pulse-air-jet-assisted water flow, particle removal efficiency, air pollution control

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