Search results for: biodegradable poly(ester amide)s

Authors: F. Siahmed, A. Lounis, L. Faghi

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The aim of this work is to study mechanical properties of composites based on fiber natural. This material has attracted attention of the scientific community for its mechanical properties, its moderate cost and its specification as regards the protection of environment. In this study the loofah part of the family of the natural fiber has been used for these significant mechanical properties. The fiber has porous structure, which facilitates the impregnation of the resin through these pores. The matrix used in this study is the type of unsaturated polyester. This resin was chosen for its resistance to long term.The work involves: -The chemical treatment of the fibers of loofah by NaOH solution (5%) -The realization of the composite resin / fiber loofah; The preparation of samples for testing -The tensile tests and bending -The observation of facies rupture by scanning electron microscopy The results obtained allow us to observe that the values of Young's modulus and tensile strength in tension is high and open up real prospects. The improvement in mechanical properties has been obtained for the two-layer composite fiber with 7.5% (by weight).

Keywords: loofah fiber, mechanical properties, composite, loofah fiber resin

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Authors: Daniel R. McDougall, Martin D. de Jonge, Gordon M. Miskelly, Duncan J. McGillivray, Andrew G. Jeffs

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The chelating agent ethylenediaminetetraacetic acid (EDTA) is commonly added as a cure-all to seawater in aquaculture hatcheries around the world to reduce heavy metal toxicity, significantly improve the survival of larval shellfish, and to therefore improve the overall production efficiency of the aquaculture industry. However, EDTA is not a biodegradable chemical and is considered to be a persistent organic pollutant, which will accumulate in the environment over time. This makes the use of EDTA unsustainable environmentally, and therefore alternatives should be considered. Ethylenediaminedisuccinic acid (EDDS) is a biodegradable alternative to EDTA with very similar metal chelation properties. This study investigates the effect of EDTA and EDDS at two different concentrations, on metal concentrations found within developing New Zealand green-lipped mussel (Perna canaliculus) larvae. P. canaliculus is New Zealand’s main shellfish aquaculture species, providing a major export for New Zealand’s economy, with excellent potential for increased production in the near future. It is well known that the early stages of bivalve development are the most vulnerable to metal toxicity and P. canaliculus is no exception. The commercially used concentration (12 µmol L⁻¹) of EDTA added to P. canaliculus larval rearing tanks often increases the yield of D-larvae by over 80%. This concentration of EDTA and EDDS will be tested in this study, along with a lower concentration (3 µmol L⁻¹). After 48 hours of larval development, the D-larvae will be analyzed for heavy metal content with Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and heavy metal distribution with synchrotron X-ray Fluorescence Microscopy (XFM). In this study, we found that EDDS also improves the yield of P. canaliculus larvae and could be a viable alternative to EDTA in aquaculture. Furthermore, results suggest a higher concentration of chelating agent is more effective for improving the yield of developing P. canaliculus larvae. Metals with significant differences in concentration with the addition of EDTA were Cr, Cu, Zn, Cd and Pb (P < 0.05). We observed for the first time to the author’s best knowledge, metal distribution within 100 µm P. canaliculus D-larvae using synchrotron XFM and found changes in the distribution of metals with the addition of EDTA. XFM also has the potential to provide information about the chemical state of the metals within mussel larvae. This research provides greater insight into the reasons for the effectiveness of adding the chelating agent to aquaculture culture water, and a more environmentally conscious alternative to the currently used EDTA, which could be extremely valuable for the aquaculture industry.

Keywords: EDDS, EDTA, heavy metals, P. canaliculus, toxicity, water treatment

Procedia PDF Downloads 186

Authors: Jawairia Umar, Tanveer Hussain, Zulfiqar Ali, Muhammad Maqsood

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Different knitted structures and knitted parameters play a vital role in the stretch and recovery management of compression sportswear in addition to the materials use to generate this stretch and recovery behavior of the fabric. The present work was planned to predict the different performance indicators of a compression sportswear fabric with some ground parameters i.e. base yarn stitch length (polyester as base yarn and spandex as plating yarn involve to make a compression fabric) and linear density of the spandex which is a key material of any sportswear fabric. The prediction models were generated by response surface method for performance indicators such as stretch & recovery percentage, compression generated by the garment on body, total elongation on application of high power force and load generated on certain percentage extension in fabric. Certain physical properties of the fabric were also modeled using these two parameters.

Keywords: Compression, sportswear, stretch and recovery, statistical model, kikuhime

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Authors: Fumihiro Ima, Shinichi Watanabe, Shingo Maeda, Haruna Imai, Hiroki Niimi

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It is important to know growth rate of brain tumors before surgery because it influences treatment planning including not only surgical resection strategy but also adjuvant therapy after surgery. Amide proton transfer (APT) imaging is an emerging molecular magnetic resonance imaging (MRI) technique based on chemical exchange saturation transfer without administration of contrast medium. The underlying assumption in APT imaging of tumors is that there is a close relationship between the proliferative activity of the tumor and mobile protein synthesis. We aimed to evaluate the diagnostic performance of APT imaging of pre-and post-treatment brain tumors. Ten patients with brain tumor underwent conventional and APT-weighted sequences on a 3.0 Tesla MRI before clinical intervention. The maximum and the minimum APT-weighted signals (APTWmax and APTWmin) in each solid tumor region were obtained and compared before and after clinical intervention. All surgical specimens were examined for histopathological diagnosis. Eight of ten patients underwent adjuvant therapy after surgery. Histopathological diagnosis was glioma in 7 patients (WHO grade 2 in 2 patients, WHO grade 3 in 3 patients and WHO grade 4 in 2 patients), meningioma WHO grade1 in 2 patients and primary lymphoma of the brain in 1 patient. High-grade gliomas showed significantly higher APTW-signals than that in low-grade gliomas. APTWmax in one huge parasagittal meningioma infiltrating into the skull bone was higher than that in glioma WHO grade 4. On the other hand, APTWmax in another convexity meningioma was the same as that in glioma WHO grade 3. Diagnosis of primary lymphoma of the brain was possible with APT imaging before pathological confirmation. APTW-signals in residual tumors decreased dramatically within one year after adjuvant therapy in all patients. APT imaging demonstrated excellent diagnostic performance for the planning of surgery and adjuvant therapy of brain tumors.

Keywords: amides, magnetic resonance imaging, brain tumors, cell proliferation

Procedia PDF Downloads 119

Authors: Fumihiro Imai, Shinichi Watanabe, Shingo Maeda, Haruna Imai, Hiroki Niimi

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It is important to know the growth rate of brain tumors before surgery because it influences treatment planning, including not only surgical resection strategy but also adjuvant therapy after surgery. Amide proton transfer (APT) imaging is an emerging molecular magnetic resonance imaging (MRI) technique based on chemical exchange saturation transfer without the administration of a contrast medium. The underlying assumption in APT imaging of tumors is that there is a close relationship between the proliferative activity of the tumor and mobile protein synthesis. We aimed to evaluate the diagnostic performance of APT imaging of pre-and post-treatment brain tumors. Ten patients with brain tumor underwent conventional and APT-weighted sequences on a 3.0 Tesla MRI before clinical intervention. The maximum and the minimum APT-weighted signals (APTWmax and APTWmin) in each solid tumor region were obtained and compared before and after a clinical intervention. All surgical specimens were examined for histopathological diagnosis. Eight of ten patients underwent adjuvant therapy after surgery. Histopathological diagnosis was glioma in 7 patients (WHO grade 2 in 2 patients, WHO grade 3 in 3 patients, and WHO grade 4 in 2 patients), meningioma WHO grade 1 in 2 patients, and primary lymphoma of the brain in 1 patient. High-grade gliomas showed significantly higher APTW signals than that low-grade gliomas. APTWmax in one huge parasagittal meningioma infiltrating into the skull bone was higher than that in glioma WHO grade 4. On the other hand, APTWmax in another convexity meningioma was the same as that in glioma WHO grade 3. Diagnosis of primary lymphoma of the brain was possible with APT imaging before pathological confirmation. APTW signals in residual tumors decreased dramatically within one year after adjuvant therapy in all patients. APT imaging demonstrated excellent diagnostic performance for the planning of surgery and adjuvant therapy of brain tumors.

Keywords: amides, magnetic resonance imaging, brain tumors, cell proliferation

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Authors: Showmitra Chowdhury, M. Shahadat Hossain, S. M. Sharifuzzaman, Sayedur Rahman Chowdhury, Subrata Sarker, M. Shah Nawaz Chowdhury

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Microplastics were identified in mussel (Pernaviridis) and Oyster (Crassostrea madrasensis) from the south east coast of Bangladesh. Samples were collected from four sites of the coast based on their availability, and gastrointestinal tracts were assessed following isolation, floatation, filtration, microscopic observation, and polymer identification by micro-Fourier Transformed Infrared Spectroscope (μ-FTIR) for microplastics determination. A total of 1527 microplastics were identified from 130 samples. The amount of microplastics varied from 0.66 to 3.10 microplastics/g and from 3.20 to 27.60 items/individual. Crassostrea madrasensiscontained on average 1.64 items/g and exhibited the highest level of microplastics by weight. Fiber was the most dominant type, accounting for 72% of total microplastics. Polyethylene, polypropylene, polystyrene, polyester, and nylon were the major polymer types. In both species, transparent/ black color and filamentous shape was dominant. The most common size ranges from 0.005 to 0.25mm and accounted for 39% to 67%. The study revealed microplastics pollution is widespread and relatively high in the bivalves of Bangladesh.

Keywords: microplastics, bivalves, mussel, oyster, bay of bengal, Bangladesh

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Authors: A. Benhadji, M. Taleb Ahmed

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Among the various methods of treatment, advanced oxidation processes (AOP) are the most promising ones. In this study, Peroxi Electrocoagulation Process (PEP) was investigated for the treatment of detergent wastewater. The process was compared with electrooxidation treatment. The results showed that chemical oxygen demand (COD) was high 7584 mgO₂.L^-1, while the biochemical oxygen demand was low (250 mgO₂.L^-1). This wastewater was hardly biodegradable. Electrochemical process was carried out for the removal of detergent using a glass reactor with a volume of 1 L and fitted with three electrodes. A direct current (DC) supply was used. Samples were taken at various current density (0.0227 A/cm² to 0.0378 A/cm²) and reaction time (1-2-3-4 and 5 hour). Finally, the COD was determined. The results indicated that COD removal efficiency of PEP was observed to increase with current intensity and reached to 77% after 5 h. The highest removal efficiency was observed after 5 h of treatment.

Keywords: AOP, COD, detergent, PEP, wastewater

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Authors: Richu J. Babu, Sony Mathew, Sharon Rony Jacob, Soney C. George, Jibin C. Jacob

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Human hair is a non-biodegradable waste available in plenty throughout the world but is rarely explored for applications in engineering fields. Tensile strength of human hair ranges from 170 to 220 MPa. This property of human hair can be made use in the field of making bio-composites[1]. The composite is prepared by commixing the human hair and natural rubber in a two roll mill along with additives followed by vulcanization. Here the concentration of the human hair is varied by fine-tuning the fiber length as 20 mm and sundry tests like tensile, abrasion, tear and hardness were conducted. While incrementing the fiber length up to a certain range the mechanical properties shows superior amendments.

Keywords: human hair, natural rubber, composite, vulcanization, fiber loading

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Authors: Ashraf Shebl, Bassam Garah, Radah Youssef

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Sexual assault is usually a hidden crime where the only witnesses are the victim and the assailant. For a variety of reasons, even the victim may be unable to provide a detailed account of the assault or the identity of the perpetrator. Often the case history deteriorates into one person’s word against another. With such limited initial information, the physical and biological evidence collected from the victim, from the crime scene, and from the suspect will play a pivotal role in the objective and scientific reconstruction of the events in question. The aim of work is to examine whether DNA profiles could be recovered from repeated washed clothes after contaminated by semen stains. Fresh semen about 1ml. ( <1 h old) taken from donor was deposited on four types of clothes (cotton, silk, polyester, and jeans). Then leave to dry in room temperature and washed by washing machine at temperature (30°C-60°C) and by hand washing. Some items of clothing were washed once, some twice and others three times. DNA could be extracted from some of these samples even after multiple washing. This study demonstrates that complete DNA profiles can be obtained from washed semen stains on different types of clothes, even after many repeated washing. These results indicated that clothes of the victims must be examined even if they were washed many times.

Keywords: sexual assault, DNA, persistence, clothes

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Authors: Deepali Lal, Sudha Summerwar, Jyoutsna Pandey

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The resistance of pesticide by the pest is an important matter of concern.The pesticide of plant origin having nontoxic biodegradable and environmentally friendly qualities. The frequent spraying of toxic chemicals is developing resistance to the pesticide. Leaf powder of the plants like Argimone mexicana and Calotropis procera is prepared, Different doses of these plant extracts are given to the Fourth in star stages of Helicoverpa armigera through feeding methods, to find their efficacy the experimental findings will be put under analysis using various parameters. The effect on paritrophic membrane is also studied.

Keywords: distillation plant, acetone, alcohol, pipette, castor leaves, grams pods, larvae of helicoverpa armigera, plant extract, vails, jars, cotton

Procedia PDF Downloads 287

Authors: Rangrong Yoksan, Amporn Sane, Nattaporn Khanoonkon, Chanakorn Yokesahachart, Narumol Noivoil, Khanh Minh Dang

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Polylactic acid (PLA) is the most commercially available bio-based and biodegradable plastic at present. PLA has been used in plastic related industries including single-used containers, disposable and environmentally friendly packaging owing to its renewability, compostability, biodegradability, and safety. Although PLA demonstrates reasonably good optical, physical, mechanical, and barrier properties comparable to the existing petroleum-based plastics, its brittleness and mold shrinkage as well as its price are the points to be concerned for the production of rigid and semi-rigid packaging. Blending PLA with other bio-based polymers including thermoplastic starch (TPS) is an alternative not only to achieve a complete bio-based plastic, but also to reduce the brittleness, shrinkage during molding and production cost of the PLA-based products. TPS is a material produced mainly from starch which is cheap, renewable, biodegradable, compostable, and non-toxic. It is commonly prepared by a plasticization of starch under applying heat and shear force. Although glycerol has been reported as one of the most plasticizers used for preparing TPS, its migration caused the surface stickiness of the TPS products. In some cases, mixed plasticizers or natural fibers have been applied to impede the retrogradation of starch or reduce the migration of glycerol. The introduction of fibers into TPS-based materials could reinforce the polymer matrix as well. Therefore, the objective of the present research is to study the effect of starch type (i.e. native starch and phosphate starch), plasticizer type (i.e. glycerol and xylitol with a weight ratio of glycerol to xylitol of 100:0, 75:25, 50:50, 25:75, and 0:100), and fiber content (i.e. in the range of 1-25 % wt) on properties of PLA/TPS blend and composite. PLA/TPS blends and composites were prepared using a twin-screw extruder and then converted into dumbbell-shaped specimens using an injection molding machine. The PLA/TPS blends prepared by using phosphate starch showed higher tensile strength and stiffness than the blends prepared by using the native one. In contrast, the blends from native starch exhibited higher extensibility and heat distortion temperature (HDT) than those from the modified starch. Increasing xylitol content resulted in enhanced tensile strength, stiffness, and water resistance, but decreased extensibility and HDT of the PLA/TPS blend. Tensile properties and hydrophobicity of the blend could be improved by incorporating silane treated-jute fibers.

Keywords: polylactic acid, thermoplastic starch, Jute fiber, composite, blend

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Authors: Elif Kalkanli, Constantinos Soutis

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The use of textile preform in the advanced fields including aerospace, automotive and marine has exponentially grown in recent years. These preforms offer excellent advantages such as being lightweight and low-cost, and also, their suitability for creating different fiber architectures with different materials whilst improved mechanical properties in certain aspects. In this study, a novel honeycomb core is developed by a 3Dweaving process. The assembly of the layers is achieved thanks to innovative weaving design. Polyester yarn is selected for the 3D woven honeycomb core (3DWHC). The core is used to manufacture a sandwich panel with 2x2 twill glass fiber composite face sheets. These 3DWHC sandwich panels will be tested in three-point bending. The in-plane and out-of-plane (through-the-thickness) mechanical response of the core will be examined as a function of cell size in addition to the flexural response of the sandwich panel. The failure mechanisms of the core and the sandwich skins will be reported in addition to flexural strength and stiffness. Possible engineering applications will be identified.

Keywords: 3D woven, assembly, failure modes, honeycomb sandwich panel

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Authors: Gabriela Kalcikova, Igor Bosevski, Ula Rozman, Andreja Zgajnar Gotvajn

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Antibiotics are extensively used in human medicine and also in animal husbandry to prevent or control infections. Recently, a lot of attention has been put on veterinary antibiotics, because their global consumption is increasing and it is expected to be 106.600 tons in 2030. Most of veterinary antibiotics are introduced into the environment via animal manure, which is used as fertilizer. One of such veterinary antibiotics is tiamulin. It is used the form of fumarate for treatment of pig and poultry. It is used against prophylaxis of dysentery, pneumonia and mycroplasmal infections, but its environmental impact is practically unknown. Tiamulin has been found very persistent in animal manure and thus it is expected that can be, during rainfalls, transported into the aquatic environment and affect various organisms. For assessment of its environmental impact, it is necessary to evaluate its biodegradability and toxicity to various organisms from different levels of a food chain. Therefore, the aim of our study was to evaluate ready biodegradability and toxicity of tiamulin fumarate to various organisms. Bioassay used included luminescent bacterium Vibrio fischeri heterotrophic and nitrifying microorganisms of activated sludge, water flea Daphnia magna and duckweed Lemna minor. For each species, EC₅₀ values were calculated. Biodegradability test was used for determination of ready biodegradability and it provides information about biodegradability of tiamulin under the most common environmental conditions. Results of our study showed that tiamulin differently affects selected organisms. The most sensitive organisms were water fleas with 48hEC₅₀ = 14.2 ± 4.8 mg/L and duckweed with 168hEC₅₀ = 22.6 ± 0.8 mg/L. Higher concentrations of tiamulin (from 10 mg/L) significantly affected photosynthetic pigments content in duckweed and concentrations above 80 mg/L cause visible chlorosis. It is in agreement with previous studies showing significant effect of tiamulin on green algae and cyanobacteria. Tiamuline has a low effect on microorganisms. The lower toxicity was observed for heterotrophic microorganisms (30minEC₅₀ = 1656 ± 296 mg/L), than Vibrio fisheri (30minEC₅₀ = 492 ± 21) and the most sensitive organisms were nitrifying microorganisms (30minEC₅₀ = 183 ± 127 mg/L). The reason is most probably the mode of action of tiamulin being effective to gram-positive bacteria while gram-negative (e.g., Vibrio fisheri) are more tolerant to tiamulin. Biodegradation of tiamulin was very slow with a long lag-phase being 20 days. The maximal degradation reached 40 ± 2 % in 43 days of the test and tiamulin as other antibiotics (e.g. ciprofloxacin) are not easily biodegradable. Tiamulin is widely used antibiotic in veterinary medicine and thus present in the environment. According to our results, tiamulin can have negative effect on water fleas and duckweeds, but the concentrations are several magnitudes higher than that found in any environmental compartment. Tiamulin is low toxic to tested microorganisms, but it is very low biodegradable and thus possibly persistent in the environment.

Keywords: antibiotics, biodegradability, tiamulin, toxicity

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Authors: Ju-Chun Chien

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The main purpose of this study was to figure out employees’ attitudes toward the new performance appraisal program and to examine whether three different types of appraisal processes differentially affected job satisfaction and employee engagement. The second purpose of this study was to investigate the relationship between performance appraisal reform, job satisfaction, and employee engagement. A large polyester and textile corporation had 2046 non-operational employees in February 2014. The valid participants were 1474 (72.04%) in this study. Data analysis included descriptive statistics, one-way ANOVA, one-way MANOVA, Pearson correlation, Content Validity Index, the exploratory factor analysis, and reliability analysis. The general results showed that employees who received the new performance appraisal program viewed the program more positively and showed more job satisfaction than those who did not. In particular, the implementation effects of this new performance appraisal program were most highly rated by employees who used the KPI to evaluate their job performance. Moreover, employees’ attitudes toward the new performance appraisal program were positively related to their job satisfaction and work engagement. On the other hand, most employees regarded themselves as engaged workers. To sum up, the HR department of this company has made an effective contribution to performance appraisal reforms.

Keywords: change management, employee engagement, job satisfaction, performance appraisal reform

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Authors: Slim Souissi, Mohamed Ben Amar, Nesrine Bouhamed, Pierre Marechal

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The bio-composites development from biodegradable materials and natural fibers has a growing interest in the science of composite materials. The present work was conducted as part of a cooperation project between the Sfax University and the Havre University. This work consists in developing and monitoring the properties of a composite material of olive flour wood with a polymer matrix (urea formaldehyde). For this, ultrasonic non-destructive and destructive methods of characterization were used to optimize the mechanical and acoustic properties of the studied material based on the elaboration parameters.

Keywords: bio-composite, olive flour wood, polymer matrix, ultrasonic methods, mechanical properties

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Authors: Fatimah M. Alshehrei

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For many years, synthetic pesticides have been used to kill pests; due to their toxicity and pollution, they are now a risk to human and environmental health. Lately, biopesticides have emerged as possible substitutes for petrochemical pesticides. The sources of biopesticides are widely accessible, easily biodegradable, have a variety of modes of action, are less expensive, and have little toxicity toward humans and other creatures that aren't the intended targets. Plants, bacteria, and insects are used to create biopesticides, they used in controlling diseases in crops. Microbial pesticides are produced from different microorganisms such as Trichoderma, Bacillus, Pseudomonas, and Beauveria. Also, botanical pesticides have already been commercialized; they are extracted from neem, pyrethrum, azadirachtin, etc. This paper describes biopesticide categories, their sources, mode of action, advantages and disadvantages, and their role in sustainable agriculture.

Keywords: biopesticides categories, formulation, mode of action, pest control

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Authors: Dajana Gašo-Sokač, Valentina Bušić

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Deep eutectic solvents (DES) are liquids composed of two or three safe, inexpensive components, often interconnected by noncovalent hydrogen bonds which produce eutectic mixture whose melting point is lower than that of each component. No data in literature have been found on the quaternization reaction in DES. The use of DES have several advantages: they are environmentally benign and biodegradable, easy for purification and simple for preparation. An environmentally sustainable method for preparing quaternary salts of izonicotinamide and substituted 2-bromoacetophenones was demonstrated here using choline chloride-based DES. The quaternization reaction was carried out by three synthetic approaches: conventional method, microwave and ultrasonic irradiation. We showed that the highest yields were obtained by the microwave method.

Keywords: deep eutectic solvents, izonicotinamide salts, microwave synthesis, ultrasonic irradiation

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Authors: Maryam Rahimi, Maryam Moslehishad, Seyede Marzieh Hosseini

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In this study, preparation of spray dried Carum copticum essential oil (CCEO)-loaded microcapsules by maltodextrin and its blending with two other natural biodegradable polymers, gum Arabic (GA) or modified starch (MS) were investigated. Addition of these polymers to maltodextrin resulted in the encasement of encapsulation efficiency (EE). The highest EE (78.22±0.34%) and total phenolic (TP) content (83.86±1.72 mg GAE/100g) was related to MD-MS microcapsules. CCEO-loaded microcapsules showed spherical surface, good antioxidant and antimicrobial properties. In addition, sensory tests confirmed the possible application of CCEO-loaded microcapsules as natural food additives.

Keywords: carum copticum, essential oil, encapsulation, spray drying, sensory evaluation, antioxidants

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Authors: Mariana P. Medeiros, Amanda P. Carvallo, Augusta Isaac, Milos Janecek, Peter Minarik, Mayerling Martinez Celis, Roberto. R. Figueiredo

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The effect of high pressure torsion processing on mechanical properties and corrosion behavior of pure magnesium and Mg-Zn, Mg-Zn-Ca, Mg-Li-Y, and Mg-Y-RE alloys is investigated. Micro-tomography and SEM characterization are used to estimate corrosion rate and evaluate non-uniform corrosion features. The results show the severe plastic deformation processing improves the strength of all magnesium alloys, but deformation localization can take place in the Mg-Zn-Ca and Mg-Y-RE alloys. The occurrence of deformation localization is associated with low strain rate sensitivity in these alloys and with severe corrosion localization. Pure magnesium and Mg-Zn and Mg-Li-Y alloys display good corrosion resistance with low corrosion rate and maintained integrity after 28 days of immersion in Hank`s solution.

Keywords: magnesium alloys, severe plastic deformation, corrosion, biodegradable alloys

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Authors: Tasnim Kallel, Rim Taktak

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In this experimental work, fiber reinforced polymer (FRP) composite laminates were manufactured using hand lay-up technique. The unsaturated polyester (UP) and vinylester (VE) were considered as resins reinforced with different woven fabrics (bidirectional and quadriaxial rovings). The mechanical behaviour of the resulting composites was studied and then compared. A focus was essentially done on the evaluation of the effect of E-Glass fiber and ply orientation on the mechanical properties such as tensile strength, flexural strength, and hardness of the studied composite laminates. Also, crack paths and fracture surfaces were examined, and failure mechanisms were analyzed. From the main results, it was found that the quadriaxial composite laminates (QA/VE and QA/UP) with stacking sequences of [0°, +45°, 90°, -45°] present a very ductile tensile behaviour. The other laminate samples (R500/VE, RM/VE, R500/UP and RM/UP) show a very brittle behaviour whatever the used resin. The intrinsic toughness KIC of QA/VE laminate, obtained in fracture tests, are found more important than that of RM/VE composite. Thus, the QA/VE samples, as multidirectional laminate, presents the highest interlaminar fracture resistance.

Keywords: crack growth, fiber orientation, fracture behavior, e-glass fiber fabric, laminate composite, mechanical behavior

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Authors: I. Graur, V. Bria, C. Muntenita

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Recent ecological interests have resulted in scientific concerns regarding natural-organic powder composites. Because natural-organic powders are cheap and biodegradable, green composites represent a substantial contribution in polymer science area. The aim of this study is to point out the effect of natural-organic powder resulting from the grinding of pine needles used as a modifying agent for Epiphen epoxy resin and is focused on friction coefficient behavior. A pin-on-disc setup is used for friction coefficient experiments. Epiphen epoxy resin was used with the different ratio of organic powder from the grinding of pine needles. Because of the challenges of natural organic powder, more and more companies are looking at organic composite materials.

Keywords: epoxy, friction coefficient, organic powder, pine needles

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Authors: Expedito J. S. Parente Jr., Italo C. Rios, Joao Paulo C. Marques, Rosana M. A. Saboya, F. Murilo T. Luna, Célio L. Cavalcante Jr.

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Increasing constraints of environmental regulation around the world have led to higher demand for biodegradable products. Vegetable oils present some properties that may favor their use as biolubricants; however, there are others, such as resistance to oxidation and pour point, which affect possible commercial applications. In this study, the physicochemical properties of biolubricants synthesized from different vegetable oils were evaluated and compared with petroleum-based lubricant and pure vegetable oil. Chemical modifications applied to the original vegetable oil improved their oxidative stability and pour point significantly. The addition of commercial antioxidants to the bio-based lubricants was evaluated, yielding values of oxidative stability close to those of mineral basestock oil.

Keywords: biolubricant, vegetable oil, oxidative stability, pour point, antioxidants

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Authors: Mauricio Quintero Angel, Andrés A. Duque Nivia, Carlos H. Fajardo Toro

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This paper analyzes two approaches of sustainability, the weak and strong, considering a case of study of oil palm production for an industry of biodegradable detergent. In this case, a company demand the oil palm as the active element for washing and through its trademark aims to supply 10% of the Colombian market of washing powders. Under each approach the economic and ecological implications of the palm oil production and especially the implications for crop management are described. The crop production under the weak sustainability implies plantations, intensive use of agrochemicals and the inclusion of new areas of cultivation as the market grows. Under the strong sustainability the production system is limited by the productive vocation of the ecosystem, so that new approaches and creativity for making viable the nature conservancy and the business development are require.

Keywords: agriculture, environmental impacts, oil palm, strong sustainability, weak sustainability

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Authors: Won-Gon Kim

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Introduction: The clinical value of arterial line filters is still a controversial issue. Proponents of arterial line filtration argue that filters remove particulate matter and undissolved gas from circulation, while opponents argue the absence of conclusive clinical data. We conducted scanning electron microscope (SEM) studies of arterial line filters used clinically in the CPB circuits during adult cardiac surgery and analyzed the types and characteristics of materials entrapped in the arterial line filters. Material and Methods: Twelve arterial line filters were obtained during routine hypothermic cardiopulmonary bypass in 12 adult cardiac patients. The arterial line filter was a screen type with a pore size of 40 ㎛ (Baxter Health care corporation Bentley division, Irvine, CA, U.S.A.). After opening the housing, the woven polyester strands were examined with SEM. Results and Conclusion: All segments examined(120 segments, each 2.5 X 2.5 cm in size) contained no embolic particles larger in their cross-sectional area than the pore size of the filter(40 ㎛). The origins of embolic particulates were mostly from environmental foreign bodies. This may suggest a possible need for more aggressive filtration of smaller particulates than is generally carried out at the present time.

Keywords: arterial line filter, tubing wear, scanning electron microscopy, SEM

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Authors: V. Lukášová, P. Peukert, V. Votrubec

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Thermal conductivity in the x, y and z-directions was measured on a pultruded profile that was manufactured by the technology of pulling from glass fibers and a polyester matrix. The results of measurements of thermal conductivity showed considerable variability in different directions. The caused variability in thermal conductivity was expected due fraction variations. The cross-section of the pultruded profile was scanned. An image analysis illustrated an uneven distribution of the fibers and the matrix in the cross-section. The distribution of these inequalities was processed into a Voronoi diagram in the observed area of the pultruded profile cross-section. In order to verify whether the variation of the fiber volume fraction in the pultruded profile can affect its thermal conductivity, the numerical simulations in the ANSYS Fluent were performed. The simulation was based on the geometry reconstructed from image analysis. The aim is to quantify thermal conductivity numerically. Above all, images with different volume fractions were chosen. The results of the measured thermal conductivity were compared with the calculated thermal conductivity. The evaluated data proved a strong correlation between volume fraction and thermal conductivity of the pultruded profile. Based on presented results, a modification of production technology may be proposed.

Keywords: pultrusion profile, volume fraction, thermal conductivity, numerical simulation

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Authors: Andi Setiawan, Annisa Ulfah Pristya

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Indonesian rubber plant area reached 2.9 million hectares with productivity reached 1.38 million. High rubber productivity is directly proportional to the amount of waste produced rubber processing industry. Rubber industry would produce a negative impact on the rubber industry in the form of environmental pollution caused by waste that has not been treated optimally. Rubber industrial wastewater containing high-nitrogen compounds (nitrate and ammonia) and phosphate compounds which cause water pollution and odor problems due to the high ammonia content. On the other hand, demand for NPK fertilizers in Indonesia continues to increase from year to year and in need of ammonia and phosphate as raw material. Based on domestic demand, it takes a year to 400,000 tons of ammonia and Indonesia imports 200,000 tons of ammonia per year valued at IDR 4.2 trillion. As well, the lack of phosphoric acid to be imported from Jordan, Morocco, South Africa, the Philippines, and India as many as 225 thousand tons per year. During this time, the process of wastewater treatment is generally done with a rubber on the tank to contain the waste and then precipitated, filtered and the rest released into the environment. However, this method is inefficient and thus require high energy costs because through many stages before producing clean water that can be discharged into the river. On the other hand, Indonesia has the potential of pineapple fruit can be harvested throughout the year in all of Indonesia. In 2010, production reached 1,406,445 tons of pineapple in Indonesia or about 9.36 percent of the total fruit production in Indonesia. Increased productivity is directly proportional to the amount of pineapple waste pineapple leaves are kept continuous and usually just dumped in the ground or disposed of with other waste at the final disposal. Through Eco-Nanofiltration Membrane-Based Fiber Pineapple leaves Waste so that environmental problems can be solved efficiently. Nanofiltration is a process that uses pressure as a driving force that can be either convection or diffusion of each molecule. Nanofiltration membranes that can split water to nano size so as to separate the waste processed residual economic value that N and P were higher as a raw material for the manufacture of NPK fertilizer to overcome the crisis in Indonesia. The raw materials were used to manufacture Eco-Nanofiltration Membrane is cellulose from pineapple fiber which processed into cellulose acetate which is biodegradable and only requires a change of the membrane every 6 months. Expected output target is Green eco-technology so with nanofiltration membranes not only treat waste rubber industry in an effective, efficient and environmentally friendly but also lowers the cost of waste treatment compared to conventional methods.

Keywords: biodegradable, cellulose diacetate, fertilizers, pineapple, rubber

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Authors: J. V. Thanikal, M. Torrijos, Philipe Sousbie, S. M. Rizwan, R. Senthil Kumar, Hatem Yezdi

Abstract:

Co-digestion is one of the advantages of anaerobic digestion process because; several wastes having complimentary characteristics can be treated in a single process. The anaerobic co-digestion process, which can be defined as the simultaneous treatment of two –or more – organic biodegradable waste streams by anaerobic digestion offers great potential for the proper disposal of the organic fraction of solid waste coming from source or separate collection systems. The results of biogas production for sewage sludge, when used as a single substrate, were low (350ml/d), and also the biodegradation rate was slow. Sewage sludge as a co-substrate did not show much effect on biogas yield. The vegetable substrates (Potato, Carrot, Spinach) with a total charge of 27–36 g VS, with a HRT starting from 3 days and ending with 1 day, shown a considerable increase in biogas yield 3.5-5 l/d.

Keywords: anaerobic digestion, co-digestion, vegetable substrate, sewage sludge

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Authors: Moanaro Ao, Nzanthung Ngullie

Abstract:

Municipal solid waste management (MSWM) has unique challenges in hilly urban settlements. Efforts have been taken by municipalities, private players, non-governmental organizations, etc. for managing solid waste by preventing its generation, reusing, and recovering them into useful products to the extent possible, thereby minimizing its impact on the environment and human health. However, there are many constraints that lead to inadequate management of solid waste. Kohima is an unplanned hill station city in the North Eastern Region of India. The city is facing numerous issues due to the mismanagement of the MSW generated. Kohima Municipal Council (KMC) is the Urban Local Body (ULB) responsible for providing municipal services. The present MSWM system in Kohima comprises of collection, transportation, and disposal of waste without any treatment. Several efforts and experimental projects on waste management have been implemented without any success. Waste management in Kohima city is challenging due to its remote location, difficult topography, dispersed settlements within the city, sensitive ecosystem, etc. Furthermore, the narrow road network in Kohima with limited scope for expansion, inadequate infrastructure facilities, and financial constraints of the ULB add up to the problems faced in managing solid waste. This hill station also has a unique system of traditional local self-governance. Thus, shifting from a traditional system to a modern system in implementing systematic and scientific waste management is also a challenge in itself. This study aims to analyse the existing situation of waste generation, evaluate the effectiveness of the existing management system of MSW, and evolve a strategic approach to achieve a sustainable and resilient MSWM system. The results from the study show that a holistic approach, including social aspects, technical aspects, environmental aspects, and financial aspects, is needed to reform the MSWM system. Stringent adherence to source segregation is required by encouraging public participation through awareness programs. Active involvement of community-based organizations (CBOs) has brought a positive change in sensitizing the public. A waste management model was designed to be adopted at a micro-level such as composting household biodegradable waste and incinerator plants at the community level for non-biodegradable waste. Suitable locations for small waste stations were identified using geographical information system (GIS) tools for waste recovery and recycling. Inculcating the sense of responsibility in every waste generator towards waste management by implementing incentive-based strategies at the Ward level was explored. Initiatives based on the ‘polluters pay principle’ were also explored to make the solid waste management model “self-sustaining”.

Keywords: municipal solid waste management, public participation, source segregation, sustainable

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Authors: D. Sun, L. Saw, A. Onyianta, D. O’Rourke, Z. Lu, C. See, C. Wilson, C. Popescu, M. Dorris

Abstract:

With the rapid development of wearable technology (e.g., smartwatch, activity trackers and health monitor devices), flexible dielectric materials with environmental-friendly, low-cost and high-energy efficiency characteristics are in increasing demand. In this work, a flexible dielectric nanocomposite was processed by incorporating two components: cellulose nanofibrils and alum sludge in a polymer matrix. The two components were used in the reinforcement phase as well as for enhancing the dielectric properties; they were processed using waste materials that would otherwise be disposed to landfills. Alum sludge is a by-product of the water treatment process in which aluminum sulfate is prevalently used as the primary coagulant. According to the data from a project partner-Scottish Water: there are approximately 10k tons of alum sludge generated as a waste from the water treatment work to be landfilled every year in Scotland. The industry has been facing escalating financial and environmental pressure to develop more sustainable strategies to deal with alum sludge wastes. In the available literature, some work on reusing alum sludge has been reported (e.g., aluminum recovery or agriculture and land reclamation). However, little work can be found in applying it to processing energy materials (e.g., dielectrics) for enhanced energy density and efficiency. The alum sludge was collected directly from a water treatment plant of Scottish Water and heat-treated and refined before being used in preparing composites. Cellulose nanofibrils were derived from water hyacinth, an invasive aquatic weed that causes significant ecological issues in tropical regions. The harvested water hyacinth was dried and processed using a cost-effective method, including a chemical extraction followed by a homogenization process in order to extract cellulose nanofibrils. Biodegradable elastomer polydimethylsiloxane (PDMS) was used as the polymer matrix and the nanocomposites were processed by casting raw materials in Petri dishes. The processed composites were characterized using various methods, including scanning electron microscopy (SEM), rheological analysis, thermogravimetric and X-ray diffraction analysis. The SEM result showed that cellulose nanofibrils of approximately 20nm in diameter and 100nm in length were obtained and the alum sludge particles were of approximately 200um in diameters. The TGA/DSC analysis result showed that a weight loss of up to 48% can be seen in the raw material of alum sludge and its crystallization process has been started at approximately 800°C. This observation coincides with the XRD result. Other experiments also showed that the composites exhibit comprehensive mechanical and dielectric performances. This work depicts that it is a sustainable practice of reusing such waste materials in preparing flexible, lightweight and miniature dielectric materials for wearable technology applications.

Keywords: cellulose, biodegradable, sustainable, alum sludge, nanocomposite, wearable technology, dielectric

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Authors: Imam Wierawansyah Eltara, Iftitah, Agus Ismail

Abstract:

In the present work, cellulose nanowhiskers (CNW) extracted from coconut husk fibers, were incorporated in polylactide (PLA)-based composites. Prior to the blending, PLA chains were chemically grafted on the surface of CNW to enhance the compatibilization between CNW and the hydrophobic polyester matrix. Ring-opening polymerization of L-lactide was initiated from the hydroxyl groups available at the CNW surface to yield CNW-g-PLA nanohybrids. PLA-based nanocomposites were prepared by melt blending to ensure a green concept of the study thereby limiting the use of organic solvents. The influence of PLA-grafted cellulose nanoparticles on the mechanical and thermal properties of the ensuing nanocomposites was deeply investigated. The thermal behavior and mechanical properties of the nanocomposites were determined using differential scanning calorimetry (DSC) and dynamical mechanical and thermal analysis (DMTA), respectively. In theory, evidenced that the chemical grafting of CNW enhances their compatibility with the polymeric matrix and thus improves the final properties of the nanocomposites. Large modification of the crystalline properties such as the crystallization half-time was evidenced according to the nature of the PLA matrix and the content of nanofillers.

Keywords: cellulose nanowhiskers, nanocomposites, coconut husk fiber, ring opening polymerization

Procedia PDF Downloads 291