• Computers and Concrete
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• 제17권5호
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• pp.597-612
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• 2016

The present work focuses on the use of coconut fiber in self compacting concrete. Self-Compacting Concrete (SCC) is a highly flowable, stable concrete which flows readily into place, filling formwork without any consolidation and without undergoing any significant segregation. Use of fibers in SCC bridge the cracks and enhance the performance of concrete by not allowing cracks to propagate. They contribute to an increased energy absorption compared to plain concrete. Coconut fiber has the highest toughness among all natural fibers. It is known that structures in the seismic prone areas are always under the influence of cyclic loading. To justify the importance of strengthening SCC beams with coir fiber, the present work has been undertaken. A comparison is made between cyclic and static loading of coconut fiber reinforced self compacting concrete (FRSCC) members. Using the test data obtained from the experiment, hysteresis loops were drawn and comparison of envelope curve, energy dissipation, stiffness degradation were made and important conclusions were draw to justify the use of coconut fiber in SCC.

• Advances in environmental research
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• 제1권3호
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• pp.223-236
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• 2012

Biosorption of methylene blue (MB) from aqueous solution was studied with respect to the point of zero charge of coconut husk, dye concentration, particle size, pH, temperature, as well as adsorbent and NaCl concentration using coconut husk biomass. Amongst Langmuir and Freundlich adsorption isotherms studied, Langmuir adsorption isotherm showed better agreement. Pseudo second order kinetics model was found to be more suitable for data presentation as compared to pseudo first order kinetics model. Also, involvement of diffusion process was studied using intraparticle diffusion, external mass transfer and Boyd kinetic model. Involvement of intraparticle diffusion model was found to be more relevant (prominent) as compared to external mass transfer (in) for methylene blue biosorption by the coconut husk. Moreover, thermodynamic properties of MB biosorption by coconut husk were studied. Desorption of methylene blue from biomass was studied with different desorbing agents, and the highest desorption achieved was as low as 7.18% with acetone, which indicate stable immobilization. Under the experimental conditions MB sorption was not significantly affected by pH, temperature and adsorbent concentration but low sorption was observed at higher NaCl concentrations.

• Asian Journal of Business Environment
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• 제14권1호
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• pp.15-22
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• 2024

Purpose: The development of natural batik dyes based on a combination of coconut fiber waste and avocado leaves using the extraction method is important to support the green economy and reduce chemical waste in Indonesia. Research design, data and methodology: The research explores the use of coconut fiber and avocado leaf waste extraction as a natural batik dye and conducts market testing to assess consumer satisfaction. Results: Indonesian batik exports are growing, but synthetic dye practices are causing a decline in demand. To address this, natural dyes are being explored, including coconut fiber waste and avocado leaf waste. Conclusion: Test results from washing at 40 degrees Celsius in terms of color changes and color staining, from sweat in terms of changes in acid color and changes in base color, to sunlight in terms of color fastness value, to heat to iron in terms of color change and color staining shows a value of 3-4 (quite good) and 4-5 (good), meaning that coconut fiber and avocado leaves waste can be used as natural batik dye.

• Advances in materials Research
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• 제11권4호
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• pp.299-330
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• 2022

This review article highlights the physical, mechanical, and chemical properties of coconut shells, and the fresh and hardened properties of the coconut shell concrete are summarized and were compared with other types of aggregates. Furthermore, the structural behavior in terms of flexural, shear, and torsion was also highlighted, with other properties including shrinkage, elastic modulus, and permeability of the coconut shell concrete. Based on the reviewed literature, concrete containing coconut shell as coarse aggregate with normal sand as fine showed the 28-day compressive strength between 2 and 36 MPa with the dried density range of 1865 to 2300 kg/m³. Coconut shell concretes showed a 28-day modulus of rupture and splitting tensile strength values in the ranges of 2.59 to 8.45 MPa and 0.8 to 3.70 MPa, respectively, and these values were in the range of 5-20% of the compressive strength. The flexural behavior of CSC was found similar to other types of lightweight concrete. There were no horizontal cracks on beams which indicate no bond failure. Whereas, the diagonal shear failure was prominent in beams with no shear reinforcements while flexural failure mode was seen in beams having shear reinforcement. Under torsion, CSC beams behave like conventional concrete. Finally, future recommendations are also suggested in this study to investigate the innovative lightweight aggregate concrete based on the environmental and financial design factors.

• 한국잡초학회지
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• 제30권3호
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• pp.206-214
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• 2010

The laboratory and green house studies evaluated the effect of three different environmental factors on the seed germination, seedling emergence and survival of four major weed species in coconut plantations, Mimosa pudica, Ureana lobata, Panicum maximum and Pennisetum polystachyon. Germination percentage of all the weed species was significantly reduced with increasing soil moisture stress, no germination was observed at -0.9 MPa. Germination of both grass seeds ranged from 8% to 25% and 10% to 45% as moisture stress decreased from -0.4 MPa to 0 MPa, respectively. In contrast, seeds of M. pudica, and U. lobata were moderately tolerant to soil moisture stress and best adapted to moist environment. All the weed species seeds germinated over a wide range of soil pH values with the highest germination occurring at pH 6. In all the species, seedling emergence was declined rapidly with increasing depth with the exception of U. lobata. Seedling emergence significantly declined when the duration of flooding was three days or longer in dicotyledonous weed species and two days or longer in monocotyledonous weeds. This study illustrates the adaptability of these weeds to different environmental conditions which would enable the development of management strategies to reduce their populations below economic threshold levels in coconut plantations.

• The Plant Pathology Journal
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• 제36권5호
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• pp.459-467
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• 2020

Areca palm yellow leaf (AYL) disease caused by the 16SrI group phytoplasma is a serious threat to the development of the Areca palm industry in China. The 16S rRNA gene sequence was utilized to establish a rapid and efficient detection system efficient for the 16SrI-B subgroup AYL phytoplasma in China by loop-mediated isothermal amplification (LAMP). The results showed that two sets of LAMP detection primers, 16SrDNA-2 and 16SrDNA-3, were efficient for 16SrI-B subgroup AYL phytoplasma in China, with positive results appearing under reaction conditions of 64℃ for 40 min. The lowest detection limit for the two LAMP detection assays was the same at 200 ag/μl, namely approximately 53 copies/μl of the target fragments. Phytoplasma was detected in all AYL disease samples from Baoting, Tunchang, and Wanning counties in Hainan province using the two sets of LAMP primers 16SrDNA-2 and 16SrDNA-3, whereas no phytoplasma was detected in the negative control. The LAMP method established in this study with comparatively high sensitivity and stability, provides reliable results that could be visually detected, making it suitable for application and research in rapid diagnosis of AYL disease, detection of seedlings with the pathogen and breeding of disease-resistant Areca palm varieties.

• 셀메드
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• 제5권4호
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• pp.28.1-28.6
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• 2015

This current study investigated the anti-ulcer activity of 2 types of virgin coconut oil (VCO-A and VCO-B) and coconut oil (CO). Sprague-Dawley of male rats divided into 6 groups and each group consisted of ten rats. Rats were then treated with either VCO or CO and then were then anaesthetized and pyloric ligation was performed. The anaesthesia was discontinued and the animal usually recovered consciousness within less than an hour. Three hours later, the animal was then again anaesthetized and sacrificed with chloroform. Stomach removed and its content subjected to measurement of volume and pH. The results revealed VCO-B and VCO-A (100%) significantly inhibited (p < 0.001) the volume of gastric juice secreted by the control rats by 66.81% and 51.53%, respectively. Followed by CO 42.80%. While the inhibition of gastric juice for positive control rats which treated with ranitidine (100 mg/kg) was only 22.38%. The total acid output was reduced by the oils to 70.80%, 74.16% and 40.45% for VCO-A, VCO-B and CO respectively compared to control group. Ranitidine reduced the total acid output by 34.83%. In conclusion, prevention of gastric lesions in rats by VCO was found to increase the mucous and decrease the acid volume, total acid contents and ulcer scoring. The treatment of VCO affects the all parameters that influence the initiation and perpetuation of ulceration.

• Asian-Australasian Journal of Animal Sciences
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• 제1권4호
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• pp.213-218
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• 1988

Forty eight growing bulls of two breed types(red Sahiwal and white Kilari), fed rice straw, were allocated to nine treatment groups: 1. Control straw (CS) 2. Urea upgraded straw (UUS) 3. UUS + 0.25 kg coconut cake (CC) 4. UUS + 0.75 kg CC 5. UUS + 0.25 kg rice bran (RB) 6. UUS + 1.00 kg RB 7. UUS + 0.25 kg RB + 0.25 kg CC 8. UUS + 1.00 kg RB + 0.25 kg CC 9. CS + 1.00 kg RB + 0.25 kg CC Liveweight gain was measured weekly during 15 weeks and tested in three analyses of variance. The results are: Urea upgraded straw produced a liveweight gain $180g.d^{-1}$ higher (P <0.01) than control straw. The groups supplemented with 0.25 kg coconut cake and 1.00 kg rice bran showed an increase of $100g.d^{-1}$ (p < 0.05) over the unsupplemented groups. No interaction between straw upgrading and supplementation was present (P > 0.10). Both rice bran and coconut press cake, supplemented to upgraded straw at a level of 0.25 kg, did not increase liveweight gain (P>0.05), but 1.0 kg rice bran increased gain by $90g.d^{-1}$ (P<0.05). A supplement of 0.75 kg coconut press cake to upgraded straw increased liveweight gain by $160g.d^{-1}$ compared with 0.25 kg or 0.00 kg coconut cake supplement (P<0.05). There were no significant differences between breed types (P>0.10) or interactions between breed and the other two main treatments (upgrading and supplementation). It was concluded. that both urea upgrading and supplementation of rice straw increase animal performance. The effect of urea upgrading was the same for both supplemented and unsupplemented animals. There was no indication of a nonlinear effect of supplements on growth.

• Carbon letters
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• 제9권3호
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• pp.203-209
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• 2008

The objective of this work is to study the feasibility of the preparation of the activated carbon (AC) from coconut tree flowers using high temperature fluidized bed reactor (HTFBR). The activating agent used in this work is steam. The reactor was operated at various activation temperature (650, 700, 750, 800 and $850^{\circ}C$) and activation time (30, 60, 120 and 240 min) for the production of AC from coconut tree flowers. Effect of activation time and activation temperature on the quality of the AC preparation was observed. Prepared AC was characterized in-terms of iodine number, methylene blue number, methyl violet number, ethylene glycol mono ethyl ether (EGME) surface area and SEM photographs. The best quality of AC from coconut tree flowers (CFC) was obtained at an activation temperature and time of $850^{\circ}C$ and 1 hr restectively. The effectiveness of carbon prepared from coconut tree flowers in adsorbing crystal violet from aqueous solution has been studied as a function of agitation time, carbon dosage, and pH. The adsorption of crystal violet onto AC followed second order kinetic model. Adsorption data were modeled using both Langmuir and Freundlich classical adsorption isotherms. The adsorption capacity $q_m$ was 277.78 mg/g., equilibrium time was found to be 180 min. This adsorbent from coconut tree flowers was found to be effective for the removal of CV dye.

• 공업화학
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• 제35권1호
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• pp.37-41
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• 2024

열대성 과일로 널리 재배되고 있는 코코넛(coconut)의 독특한 껍질(shell)은 과육 섭취 후 얻어지는 부산물로 활용 가치가 클 것으로 기대된다. 이 코코넛 껍질을 전도성 고분자와 혼합하여 복합소재를 간단한 방식으로 제조하고 섭씨 600도 정도의 상대적 저온에서 탄화하여 수득되는 소재의 전기화학적 특성 및 활용 가능성을 고찰하였다. 먼저, 외형적 요소를 주사전자현미경(scanning electron microscope, SEM)으로 관찰하였다. 탄소의 미세구조를 라만(Raman) 분광 분석을 통하여 추론하였다. 전기전도 가능성을 간단한 옴의 관계(Ohmic relation)를 통하여 확인하였다. 나아가, 탄화된 재료가 리튬 이차 전지의 음극(anode) 소재로 활용될 수 있는지 여부를 반쪽 전지(half-cell) 충방전(charge/discharge) 테스트를 통해 살펴보았으며, 최대 충전 용량은 약 750 mAh로 높게 나타났으나, 충전이 진행됨에 따라 빠른 감소를 보였다. 본 연구는 향후 목질계 폐기물의 활용에 대한 중요한 정보를 제공할 것이다.